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Harbin, China

The Harbin Institute of Technology is a research university and a member of the C9 League in China consisting of three campuses, which nearly span the country from north to south: the Harbin campus in Heilongjiang Province, the Weihai campus in Shandong Province and the Shenzhen graduate school in Guangdong Province.HIT undertakes research and numerous projects covered by official secrets which may have a bearing on its international ranking, although it is widely recognized as one of the top universities in the country, especially when it comes to local science and engineering league tables. HIT is one of only ten universities in the world that have designed, built, and launched their own satellites . It made the largest contribution to the success of the Shenzhou series spacecraft and Kuaizhou series spacecraft. One minor planet is named after the Harbin Institute of Technology and nicknamed "Hagongda Star" by the International Astronomical Union for HIT's achievements in science and engineering. Wikipedia.


Chen H.,Harbin Institute of Technology | Sun D.,City University of Hong Kong
IEEE Transactions on Robotics | Year: 2012

Significant demand for both accuracy and productivity in batch manipulation of microparticles highlights the need to develop an automatic arraying approach to placing groups of particles into a predefined array with right pairs. This paper presents our latest effort to achieve this objective using integrated robotics and holographic optical tweezers technologies, where holographic optical tweezers function as special robot end-effectors to manipulate the microparticles. Based on the physical dynamics of trapping, a potential-field-based controller is developed to drive every pair of particles to the assigned array, while preventing collisions between particles. The significance of the proposed controller lies in the capability of driving two groups of particles into a common array in right pair and controlling the interdistances between the particles in pairs. Experiments are performed to demonstrate the effectiveness of the proposed approach. © 2012 IEEE. Source


Li J.H.,Hong Kong University of Science and Technology | Li J.H.,Harbin Institute of Technology | Zhang L.M.,Hong Kong University of Science and Technology
Computers and Geotechnics | Year: 2010

Cracks are common in natural and engineered soils and provide preferential pathways for water infiltration into the soil. Statistical properties of crack geometries are important inputs for analyzing preferential flows in discrete random crack networks. This paper reports the outcome of a field study conducted on a compacted, cracked soil ground at a steady moisture condition. The objectives of the field study were to investigate the crack patterns and probability distributions of the geometric parameters of cracks and to determine the representative elementary volume (REV) of the crack network. The desiccation cracks at the survey site formed an inter-connected columnar structure. The traces of the cracks on the soil surface formed a primary structure consisting of inter-connected crack polygons and a secondary structure comprising of isolated cracks. The locations and orientations of the desiccation cracks followed a uniform distribution, differing from the distribution of fracture sets often observed in fractured rocks. The lengths and apertures of the cracks followed a lognormal distribution as expected. The REV size for the cracked soil was found to be approximately five times the mean crack length, above which the variation in crack porosity in relation to domain size was negligible. © 2010 Elsevier Ltd. Source


Li H.,Bohai University | Gao H.,Harbin Institute of Technology | Gao H.,King Abdulaziz University | Shi P.,University of Adelaide | And 2 more authors.
Automatica | Year: 2014

This paper is concerned with the stabilization problem for a class of Markovian stochastic jump systems against sensor fault, actuator fault and input disturbances simultaneously. In the proposed approach, the original plant is first augmented into a new descriptor system, where the state vector, disturbance vector and fault vector are assembled into the state vector of the new system. Then, a novel augmented sliding mode observer is presented for the augmented system and is utilized to eliminate the effects of sensor faults and disturbances. An observer-based mode-dependent control scheme is developed to stabilize the resulting overall closed-loop jump system. A practical example is given to illustrate the effectiveness of the proposed design methodology. © 2014 Elsevier Ltd. All rights reserved. Source


Gu B.,Arizona State University | Ye Q.,Harbin Institute of Technology
Production and Operations Management | Year: 2014

With the growing influence of online social media, firms increasingly take an active role in interacting with consumers in social media. For many firms, their first step in online social media is management responses, where the management responds to customers' comments about the firm or its products and services. In this article, we measure the impact of management responses on customer satisfaction using data retrieved from a major online travel agency in China. Applying a panel data model that controls for regression toward the mean and heterogeneity in individual preference for hotels, we find that online management responses are highly effective among low satisfaction customers but have limited influence on other customers. Moreover, we show that the public nature of online management responses introduces a new dynamic among customers. Although online management responses increase future satisfaction of the complaining customers who receive the responses, they decrease future satisfaction of complaining customers who observe but do not receive management responses. The result is consistent with the peer-induced fairness theory. © 2013 Production and Operations Management Society. Source


Lai X.,CAS Institute of Process Engineering | Halpert J.E.,CAS Institute of Process Engineering | Wang D.,CAS Institute of Process Engineering | Wang D.,Harbin Institute of Technology
Energy and Environmental Science | Year: 2012

Hollow micro-/nano-structured materials are now playing an important role in cutting edge innovations for energy conversion and storage technologies such as solar cells, fuel cells, lithium ion batteries and super capacitors. These materials show great promise in addressing growing environmental concerns for cleaner power sources at a time of increasing global demand for energy. In this perspective, we show that complex multi-shelled micro-/nano-materials show significant material advantages in many applications over conventional simple hollow structures. We also summarize the vast array of synthetic strategies used to create multi-shelled hollow structures, and discuss the possible application of these novel materials for power generation and storage. Finally, the emergent challenges and future developments of multi-shelled hollow structures are further discussed. © The Royal Society of Chemistry 2012. Source


Wu L.,Harbin Institute of Technology | Feng Z.,University of Hong Kong | Zheng W.X.,University of Western Sydney
IEEE Transactions on Neural Networks | Year: 2010

This paper is concerned with the problem of exponential stability analysis of continuous-time switched delayed neural networks. By using the average dwell time approach together with the piecewise Lyapunov function technique and by combining a novel Lyapunov-Krasovskii functional, which benefits from the delay partitioning method, with the free-weighting matrix technique, sufficient conditions are proposed to guarantee the exponential stability for the switched neural networks with constant and time-varying delays, respectively. Moreover, the decay estimates are explicitly given. The results reported in this paper not only depend upon the delay but also depend upon the partitioning, which aims at reducing the conservatism. Numerical examples are presented to demonstrate the usefulness of the derived theoretical results. © 2006 IEEE. Source


Sun C.-L.,Taiyuan University of Science and Technology | Zeng J.-C.,Taiyuan University of Science and Technology | Pan J.-S.,Harbin Institute of Technology | Pan J.-S.,National Kaohsiung University of Applied Sciences
Information Sciences | Year: 2011

Increasing attention is being paid to solve constrained optimization problems (COP) frequently encountered in real-world applications. In this paper, an improved vector particle swarm optimization (IVPSO) algorithm is proposed to solve COPs. The constraint-handling technique is based on the simple constraint-preserving method. Velocity and position of each particle, as well as the corresponding changes, are all expressed as vectors in order to present the optimization procedure in a more intuitively comprehensible manner. The NVPSO algorithm [30], which uses one-dimensional search approaches to find a new feasible position on the flying trajectory of the particle when it escapes from the feasible region, has been proposed to solve COP. Experimental results showed that searching only on the flying trajectory for a feasible position influenced the diversity of the swarm and thus reduced the global search capability of the NVPSO algorithm. In order to avoid neglecting any worthy position in the feasible region and improve the optimization efficiency, a multi-dimensional search algorithm is proposed to search within a local region for a new feasible position. The local region is composed of all dimensions of the escaped particle's parent and the current positions. Obviously, the flying trajectory of the particle is also included in this local region. The new position is not only present in the feasible region but also has a better fitness value in this local region. The performance of IVPSO is tested on 13 well-known benchmark functions. Experimental results prove that the proposed IVPSO algorithm is simple, competitive and stable. © 2010 Elsevier Inc. All rights reserved. Source


Su X.,Chongqing University | Wu L.,Harbin Institute of Technology | Shi P.,University of Adelaide | Shi P.,Victoria University of Melbourne | Song Y.-D.,Chongqing University
Automatica | Year: 2014

This paper investigates the problem of Hankel-norm output feedback controller design for a class of T-S fuzzy stochastic systems. The full-order output feedback controller design technique with the Hankel-norm performance is proposed by the fuzzy-basis-dependent Lyapunov function approach and the conversion on the Hankel-norm controller parameters. Sufficient conditions are established to design the controllers such that the resulting closed-loop system is stochastically stable and satisfies a prescribed performance. The desired output feedback controller can be obtained by solving a convex optimization problem, which can be efficiently solved by standard numerical algorithms. Finally, a Henon map system is used to illustrate the effectiveness of the proposed techniques. © 2014 Elsevier Ltd. All rights reserved. Source


Wang M.,Harbin Institute of Technology | Lv G.,Nanjing Southeast University
Nonlinearity | Year: 2010

This paper is concerned with the entire solution of a diffusive and competitive Lotka-Volterra type system with nonlocal delays. The existence of the entire solution is proved by transforming the system with nonlocal delays to a four-dimensional system without delay and using the comparing argument and the sub-super-solution method. Here an entire solution means a classical solution defined for all space and time variables, which behaves as two wave fronts coming from both sides of the x-axis. © 2010 IOP Publishing Ltd & London Mathematical Society. Source


Shi X.,Montana State University | Xie N.,Harbin Institute of Technology | Fortune K.,Montana State University | Gong J.,Wuhan Polytechnic University
Construction and Building Materials | Year: 2012

Concrete is a unique composite material that is porous and highly heterogeneous. The durability of steel reinforced concrete in chloride environments is of great interest to design engineers, infrastructure owners and maintainers, and researchers. This review reports recent advances in the knowledge base relevant to the durability of steel reinforced concrete in chloride environments, including: the role of mineral admixtures in concrete durability, the methods of measuring the chloride ingress into concrete, the challenges in assessing concrete durability from its chloride diffusivity, and the service life modeling of reinforced concrete in chloride-laden environments. It concludes with a look to the future, including research needs to be addressed. © 2011 Elsevier Ltd. All rights reserved. Source


Shi L.,Harbin University of Science and Technology | Shen Q.,Harbin University of Science and Technology | Qiu Z.,Harbin Institute of Technology
Journal of Luminescence | Year: 2014

Er-doped and Er/Yb-codoped LiTaO3 polycrystals were synthesized by the solid-state reaction method at 1200 C. The structural properties of Er/Yb:LiTaO3 polycrystals were confirmed by the X-ray diffraction patterns. The upconversion emission spectra of Er:LiTaO3 polycrystals showed that the intensities of the green and red upconversion emissions enhanced with the increasing concentration of Er3+ ions. The increased intensity ratio of the red to green emission was attributed to the two cross relaxation processes 4S3/2+4I 15/2→4I9/2+4I13/2 and 2H11/2+4I11/2→ 4F9/2+4F9/2. Upconversion emission tuning from green to red was observed in Er/Yb:LiTaO3 polycrystals under 980 nm excitation. It was proposed that the efficient cross relaxation process (4F7/2+4I11/2→ 4F9/2+4F9/2) and the energy back transfer (4S3/2 Er+2F7/2 Yb→4I13/2 Er+2F5/2 Yb) contribute the increased intensity ratio of the red to green emission in Er/Yb:LiTaO3 polycrystals. Studies on the pump power dependence indicated that the green emitting 4S3/2/2H 11/2 states and the red emitting 4F9/2 state were populated via the energy transfer assisted UC process besides a two-photon process in Er/Yb:LiTaO3 polycrystals. © 2013 Elsevier B.V. Source


Wang S.,Beihang University | Li Y.,Beihang University | Zhang X.,Harbin Institute of Technology
Materials and Design | Year: 2013

ZrB2-SiC nanocomposite ceramics toughened by ZrO2 fiber were fabricated by spark plasma sintering (SPS) at 1700°C. The content of ZrO2 fiber incorporated into the ZrB2-SiC nanocomposites ranged from 5mass% to 20mass%. The content, microstructure, and phase transformation of ZrO2 fiber exhibited remarkable effects on the fracture toughness of the ZrO2(f)/ZrB2-SiC composites. Fracture toughness of the composites greatly improved to a maximum value of 6.56MPam1/2±0.3MPam1/2 by the addition of 15mass% of ZrO2 fiber. The microstructure of the ZrO2 fiber exhibited certain alterations after the SPS process, which enhanced crack deflection and crack bridging and affected fracture toughness. Some microcracks were induced by the phase transformation from t-ZrO2 to m-ZrO2, which was also an important reason behind the improvement in toughness. © 2013. Source


Zhou B.,Harbin Institute of Technology | Lin Z.,University of Virginia
Automatica | Year: 2014

We study in this paper the consensus problem for multi-agent systems with agents characterized by high-order linear systems with time delays in both the communication network and inputs. Provided that the open-loop dynamics of the agents is not exponentially unstable, but may be polynomially unstable, and the communication topology contains a directed spanning tree, a truncated predictor feedback approach is established to solve the consensus problem. It is shown that, if the delays are constant and exactly known, the consensus problems can be solved by both full state feedback and observer based output feedback protocols for arbitrarily large yet bounded delays. If it is further assumed that the open-loop dynamics of the agents only contains zero eigenvalues, the delays are allowed to be time-varying and unknown. Numerical examples are worked out to illustrate the effectiveness of the proposed approaches. © 2013 Elsevier Ltd. All rights reserved. Source


Niu B.,Harbin University of Science and Technology | Guo Y.,Harbin Institute of Technology
Physica D: Nonlinear Phenomena | Year: 2014

Distributed delay interactions among a group of Kuramoto phase oscillators are studied from the viewpoint of bifurcation analysis. After restricting the system on the Ott-Antonsen manifold, a simplified model consisting of delay differential equations is obtained. Hopf bifurcation diagrams are drawn on some two-parameter planes around the incoherent state when delay follows Dirac, uniform, Gamma and normal distributions, respectively, and it is illustrated that stronger coupling is needed to achieve synchrony when increasing the variance of either natural frequency or time delay. With the aid of center manifold reduction and the normal form method, the direction of Hopf bifurcation and stability of bifurcating periodic solutions are investigated, and the existence of the hysteresis loop is explained theoretically. © 2013 Elsevier B.V. All rights reserved. Source


Zhao J.,Harbin Institute of Technology
Computers in Human Behavior | Year: 2010

During the epoch of knowledge-based economy and knowledge management, teachers must learn in order to improve professional development. The paper discusses on the problems of teacher professional development in China, and analyze on the relationship among teacher learning, teacher professional development and school knowledge management. From the perspective of schools, this study develops school knowledge management framework to facilitate teacher learning and improve teacher professional development, in the basis of this framework, schools' knowledge management strategies are presented, and provide references for administrators of schools. The result reveals the knowledge management strategies to improve teacher professional development, including school organizational reforger and knowledge leaders, constructing learning school and organization learning culture, establishing teacher knowledge management system of teacher professional development, encouraging team learning, teaching cooperation and knowledge sharing, establishing performance assessment mechanism of knowledge applications and development. © 2009 Elsevier Ltd. All rights reserved. Source


Zhao X.,China University of Petroleum - East China | Shi P.,Victoria University of Melbourne | Shi P.,University of Adelaide | Zhang L.,Harbin Institute of Technology
Systems and Control Letters | Year: 2012

The stabilization problem for a class of switched linear systems with average dwell time (ADT) switching is reinvestigated in this paper. State-feedback controllers are designed, which takes the more practical case, asynchronous switching, into account, where the so-called "asynchronous switching" indicates that the switchings between the controllers and the system modes are in the presence of a time delay. By combining the asynchronous switching, an improved stabilization approach is given, and existence conditions of the controllers associated with the corresponding ADT switching are formulated in terms of a set of linear matrix inequalities. A numerical example is given to show the validity and potential of the obtained theoretical results. © 2012 Elsevier B.V. All rights reserved. Source


Hu Q.,Tianjin University | Zhang L.,Hong Kong Polytechnic University | An S.,Northeastern University China | Zhang D.,Hong Kong Polytechnic University | Yu D.,Harbin Institute of Technology
IEEE Transactions on Fuzzy Systems | Year: 2012

Rough sets, especially fuzzy rough sets, are supposedly a powerful mathematical tool to deal with uncertainty in data analysis. This theory has been applied to feature selection, dimensionality reduction, and rule learning. However, it is pointed out that the classical model of fuzzy rough sets is sensitive to noisy information, which is considered as a main source of uncertainty in applications. This disadvantage limits the applicability of fuzzy rough sets. In this paper, we reveal why the classical fuzzy rough set model is sensitive to noise and how noisy samples impose influence on fuzzy rough computation. Based on this discussion, we study the properties of some current fuzzy rough models in dealing with noisy data and introduce several new robust models. The properties of the proposed models are also discussed. Finally, a robust classification algorithm is designed based on fuzzy lower approximations. Some numerical experiments are given to illustrate the effectiveness of the models. The classifiers that are developed with the proposed models achieve good generalization performance. © 1993-2012 IEEE. Source


Ma K.,Harbin Institute of Technology | Khalil H.K.,Michigan State University
IEEE Transactions on Automatic Control | Year: 2010

In [1] , Serrani, Isidori, and Marconi design an output feedback controller that achieves semiglobal output regulation for a class of minimum phase nonlinear systems. The controller has three components: an internal model to ensure asymptotic regulation, a high-gain partial state feedback controller to stabilize the augmented system of the plant and internal model, and a high-gain observer to implement the partial state feedback. In this note we show a property of the transient response of this controller. We consider an alternate controller that shares with the controller of [1] the structure of high-gain partial state feedback and high-gain observer, but without internal model. Such controller can only achieve practical regulation. We show that when the controller and observer gains are large enough, the trajectories under the two controllers will be close to each other. Hence, the transient response of the controller of is not degraded by the inclusion of internal model. A similar transient response property is shown by Seshagiri and Khalil for the conditional servocompensator. Similarities and differences between the two designs are pointed out. © 2006 IEEE. Source


Deng L.,Nanjing University | Du Y.,Harbin Institute of Technology | Xu J.-J.,Nanjing University | Chen H.-Y.,Nanjing University
Biosensors and Bioelectronics | Year: 2014

This work demonstrates an aptasensor for ultrasensitive electrochemiluminescence (ECL) detection of thrombin based on an "off-on-off" approach. The system is composed of an Eu3+-doped CdS nanocrystals (CdS:Eu NCs) film on glassy carbon electrode (GCE) as ECL emitter. Then gold nanoparticles (AuNPs) labeled hairpin-DNA probe (ssDNA1) containing thrombin-binding aptamer (TBA) sequence was linked on the NCs film, which led to ECL quenching (off) as a result of Förster-resonance energy transfer (FRET) between the CdS:Eu NC film and the proximal AuNPs. Upon the occurrence of hybridization with its complementary DNA (ssDNA2), an ECL enhancement (on) occurred owing to the interactions of the excited CdS:Eu NCs with ECL-induced surface plasmon resonance (SPR) in AuNPs at large separation. Thrombin could induce ssDNA1 forming a G-quadruplex and cause the AuNPs to be close to CdS:Eu NCs film again, which resulted in an enhanced ECL quenching (off). This "off-on-off" system showed a maximum 7.4-fold change of ECL intensity due to the configuration transformation of ssDNA1 and provides great sensitivity for detection of thrombin in a wide detection range from 50aM to 1pM. © 2014 Elsevier B.V. Source


Jingzhuo J.,Henan University of Science and Technology | Liu B.,Harbin Institute of Technology
IEEE Transactions on Industrial Electronics | Year: 2011

The operational efficiency of ultrasonic motor motion control systems is much lower than that of traditional electromagnetic motors, which badly restricts the application of ultrasonic motor in portable devices. Lower efficiency, robustness, and wear condition are the main problems of ultrasonic motor systems. This paper studies on the optimum efficiency control strategy of an ultrasonic motor system and selects the commercially used ultrasonic motor Shinsei USR60 as the experimental motor. To provide a basis for the optimum efficiency control, the control characteristic of system efficiency is studied first under speed closed-loop control condition. Then, a novel feedforward speed controller compounded with a pole-assignment controller is designed to compensate the disturbance caused by the efficiency optimization process. After that, the optimum efficiency control strategy with varying step length based on fuzzy reasoning is proposed. Experiments show that the proposed optimum control methods can greatly increase the operational efficiency of the ultrasonic motor system. © 2011 IEEE. Source


Zhou B.,Harbin Institute of Technology
Systems and Control Letters | Year: 2015

This paper studies stabilization of linear systems with both state and input delays. A dynamic input-delay compensator obtained by adding integrators is established to compensate the input delays that can be arbitrarily large. With the input delay compensator, the original stabilization problem reduces to the problem of stabilizing an augmented linear time-delay system without input delay. Three methods are also proposed to design stabilizing controllers for the augmented linear time-delay system. The first method is based on linear matrix inequalities (LMIs) and the second method is based on model reduction. The third method is based on pole placement and is built for the particular case that the original time-delay system has only a pure delayed state vector on its right hand side. For this method, the optimal gain such that the decay rate of the closed-loop system is maximized is also proposed. The effectiveness of the proposed approaches is illustrated by three linear time-delay systems that are open-loop unstable. © 2015 Elsevier B.V. All rights reserved. Source


Gao B.,University of Notre Dame | Gao B.,Harbin Institute of Technology | Hartland G.V.,University of Notre Dame | Huang L.,University of Notre Dame
Journal of Physical Chemistry Letters | Year: 2013

We present femtosecond transient absorption measurements of individual metallic single-wall carbon nanotubes (SWNTs) to elucidate environmental effects on their spectroscopy and dynamics. Isolated suspended SWNTs were located using atomic force microscopy, and Raman spectroscopy was employed to determine the chiral index of select nanotubes. Transient absorption spectra of the SWNTs were obtained by recording transient absorption images at different probe wavelengths. This unique experimental approach removes sample heterogeneity in ultrafast measurements of these complex materials and provides a direct means to unravel the role of the substrate. The results show a ∼40 meV red shift of the lowest exciton transition, which is attributed to dielectric screening effects by the substrate. Energy relaxation in individual metallic nanotubes was observed with decay constants of a few hundred fs and about 10 ps. We attributed the fast and slow decay components to carrier scattering by optical and acoustic phonons, respectively. © 2013 American Chemical Society. Source


Ma Y.,Harbin Institute of Technology | Yeh L.-H.,National Yunlin University of Science and Technology | Qian S.,Old Dominion University
Electrochemistry Communications | Year: 2014

Analytical expressions for the pH-regulated ionic current/conductance in a cylindrical nanopore are derived for taking into account practical effects of multiple ionic species, surface chemistry reactions, and electroosmotic flow. Our model is verified by the experimental data of the conductance in the silica nanopore available in the literature. The validated analytical models are applicable to investigate electrokinetic ion transport, and to design the next-generation nanopore-based devices. © 2014 Elsevier B.V. Source


Song H.,Zhejiang University of Finance and Economics | Liu G.-P.,University of South Wales | Liu G.-P.,Harbin Institute of Technology | Yu L.,Zhejiang University of Technology
IEEE Transactions on Industrial Electronics | Year: 2013

This paper studies the design and stability analysis of uncertain networked control systems with multiple feedback channels. An observer-based networked predictive control (NPC) method is proposed to compensate for the distributed delays and packet dropouts in the feedback channels. Sufficient conditions are presented for the closed-loop NPC system with distributed delays and packet dropouts to be stable, both in constant and random cases. A ball-and-beam system is employed to test the proposed method. Both the simulation and experiment results demonstrate the effectiveness of the method. © 1982-2012 IEEE. Source


Wang X.,Harbin Institute of Technology
International Journal of Control | Year: 2011

In this article, we consider the problem of optimal coverage of unknown environmental boundary using sensor networks. Since the boundary is unknown to all sensors, it is necessary for the sensors to find it first. We give a new distributed estimate policy by tracking a virtual agent using the sensor networks. Then we consider the problem of optimal coverage of the estimate boundary instead of the actual one. Moreover, an algorithm is given to deploy the sensors to the optimal configuration corresponding to the coverage problem considered in this article. © 2011 Taylor & Francis. Source


Xue S.,Old Dominion University | Yeh L.-H.,National Yunlin University of Science and Technology | Ma Y.,Harbin Institute of Technology | Qian S.,Old Dominion University
Journal of Physical Chemistry C | Year: 2014

Many experimental results demonstrated that ion transport phenomena in nanofluidic devices are strongly dependent on the surface charge property of the nanochannel. In this study, active control of the surface charge property and the streaming current, generated by a pressure-driven flow, in a pH-regulated nanochannel using a field effect transistor (FET) are analyzed for the first time. Analytical expressions for the surface charge property and the streaming current/conductance have been derived taking into account multiple ionic species, surface chemistry reactions, and the Stern layer effect. The model is validated by the experimental data of the streaming conductance in the silica nanochannel available in the literature. Results show that the pH-dependent streaming conductance of the gated silica nanochannel is consistent with its modulated zeta potential; however, the salt concentration-dependent streaming conductance might be different from the zeta potential behavior, depending on the solution pH and the gate potential imposed. The performance of the field effect modulation of the zeta potential and the streaming conductance is significant for lower solution pH and salt concentration. The results gathered are informative for the design of the next-generation nanofluidics-based power generation apparatus. © 2014 American Chemical Society. Source


Duan G.,Harbin Institute of Technology
Chinese Control Conference, CCC | Year: 2013

In this paper, a new type of high-order generalized Sylvester equations (GSEs) are investigated. Degrees of freedom is first investigated using the concept of F-coprimeness, and a complete general parametric solution in a neat explicit closed form is then established using a generalized matrix fraction right factorization. The primary feature of this solution is that the matrix F does not need to be in any canonical form, or may be even unknown a priori. The results provide great convenience to the computation and analysis of the solutions to this class of equations, and can perform important functions in many control systems analysis and design problems involving high-order dynamical systems. © 2013 TCCT, CAA. Source


Halstead S.J.,Harbin Institute of Technology
Journal of Supercritical Fluids | Year: 2013

This paper reports a molecular dynamics study of the pKW of water, pKa of HCl and pKb of NaOH in supercritical water at a pressure of 1000 atm. The extent of acid/base dissociation is known to be an important factor in the corrosion of supercritical water reaction vessels. This work describes classical molecular dynamics simulations using the SPC/e water model to gain insight into the controlling factors. The results indicate that the dissociation of water has a maximum at 448 K, whereas both the dissociation of HCl and NaOH become less favourable with increasing temperature due to a decrease in entropy. The simulation results are compared to values calculated from the generalised Born theory, and there is a qualitative agreement in the trend. © 2013 Elsevier B.V. All rights reserved. Source


Xu Y.,Harbin Institute of Technology | Zhang D.,Hong Kong Polytechnic University
Optical Engineering | Year: 2010

Multibiometrics can obtain a higher accuracy than the single biometrics by simultaneously using multiple biometric traits of the subject. We note that biometric traits are usually in the form of images. Thus, how to properly fuse the information of multiple biometric images of the subject for authentication is crucial for multibiometrics. We propose a novel image-based linear discriminant analysis (IBLDA) approach to fuse two biometric traits (i.e., bimodal biometric images) of the same subject in the form of matrix at the feature level. IBLDA first integrates two biometric traits of one subject into a complex matrix and then directly extracts low-dimensional features for the integrated biometric traits. IBLDA also enables more information to be exploited than the matching score level fusion and the decision level fusion. Compared to linear discriminant analysis (LDA), IBLDA has the following advantages: First, it can overcome the small sample size problem that conventional LDA usually suffers from. Second, IBLDA solves the eigenequation at a low computational cost. Third, when storing the scatter matrices IBLDA will not bring as heavy a memory burden as conventional LDA. We also clearly show the theoretical foundation of the proposed method. The experiment result shows that the proposed method can obtain a high classification accuracy. © 2010 Society of Photo-Optical Instrumentation Engineers. Source


Fan X.,Harbin Institute of Technology | Au O.C.,Hong Kong University of Science and Technology | Cheung N.M.,Stanford University
IEEE Transactions on Circuits and Systems for Video Technology | Year: 2010

WynerZiv video coding (WZVC) is a newly emerged video coding scheme which compresses the input video frames with the side information (SI) frames only available at the decoder. WZVC exploits the statistics between the source frame and the SI frame at the decoder by utilizing their correlation information. This correlation information is important but also difficult to estimate due to the absence of the SI frame at the encoder, and the lack of the source frame at the decoder. In this paper, we focus on this problem and propose a novel transform-domain adaptive correlation estimation method called TRACE for WZVC. In TRACE, the correlation information is progressively learned during the decoding process of each frame. Within TRACE, we also propose a convex optimization based band-level correlation estimation method which is optimal in the sense of minimizing the theoretical bit rate. Experiments suggest that, when applied in motion compensated interpolation-based low complexity WZVC, TRACE yields competitive results against the state-of-the-art correlation estimation algorithms. More importantly, different from the existing coefficient-level correlation estimation algorithms, the proposed TRACE can be applied in many other WZVC schemes and can provide considerable gain over the popular band-level correlation estimation methods. © 2006 IEEE. Source


Wu L.,Harbin Institute of Technology | Ho D.W.C.,City University of Hong Kong
Automatica | Year: 2010

This paper is concerned with the sliding mode control (SMC) of nonlinear singular stochastic systems with Markovian switching. An integral sliding surface function is designed, and the resulting sliding mode dynamics is a full-order Markovian jump singular stochastic system. By introducing some specified matrices, a new sufficient condition is proposed in terms of strict linear matrix inequality (LMI), which guarantees the stochastic stability of the sliding mode dynamics. Then, a SMC law is synthesized for reaching motion. Moreover, when there exists an external disturbance, the ℒ2 disturbance attenuation performance is analyzed for the sliding mode dynamics. Some related sufficient conditions are also established. © 2010 Elsevier Ltd. All rights reserved. Source


Zhai X.,Harbin Institute of Technology | Stewart M.G.,University of Newcastle
Engineering Structures | Year: 2010

The safety and reliability of reinforced grouted concrete block masonry is not accurately known in China. The present paper develops a probabilistic model to calculate the structural reliability of typical reinforced grouted concrete block masonry walls designed to Chinese standards, loaded concentrically and eccentrically in compression. The effect of probability distribution of model error, material strengths, live load type, structural safety class, live-to-dead ratio, reinforcement ratio, discretization of wall thickness, eccentricity and load effect combination were considered when calculating the structural reliability of reinforced grouted concrete block masonry walls in compression. When using the recommended distribution of model error for typical structures the existing (design) safety levels were found to be close to the target reliability for concentric compression for second class safety grade structures which comprise the majority of building stock in China. However, the reliability-based code calibration showed that design loads could be increased and decreased by 13.6% and 16.7% for first and third class safety grade structures, respectively. © 2009 Elsevier Ltd. Source


Zhao Y.-B.,University of Glasgow | Kim J.,University of Glasgow | Liu G.-P.,University of South Wales | Liu G.-P.,Harbin Institute of Technology
IEEE Transactions on Industrial Electronics | Year: 2011

An error bounded sensing strategy is proposed within the packet-based control framework for networked control systems (NCSs). This strategy reduces the data transmissions in both the sensor-to-controller and the controller-to-actuator channels by allowing the transmissions of only the sensing and control data packets that satisfy some predetermined transmission rules. By fitting it into the packet-based control framework for NCSs, this strategy can achieve the goal of reducing the use of the communication resources while at the same time maintaining the system performance at an acceptable level. Stabilized controllers are designed within this framework, and the effects on the system stability brought by this approach are also investigated. Numerical and experimental examples illustrate the effectiveness of the proposed approach. © 2010 IEEE. Source


Lu H.,Harbin Institute of Technology | Huang W.M.,Nanyang Technological University
Smart Materials and Structures | Year: 2013

All amorphous shape memory polymers (SMPs) are featured by their relaxation behavior above and below the switching transition temperature (TSW). Above TSW, the glass transition and secondary transition merge together, resulting in the cooperative (α) movement in polymer macromolecules. Below TSW, movement is non-cooperative (β). In this study, three thermodynamic constitutive frameworks for the shape recovery behavior in amorphous SMPs are proposed based on the Arrhenius, Vogel-Fulcher-Tammann (VFT) and Bässler laws, respectively, and incorporated with parameters (stress, strain and relaxation time) as functions of temperature. The relaxation times of α and β movements satisfy the VFT and Arrhenius laws, respectively. The simulation is compared with the available experimental results reported in the literature for verification. The VFT law is found to be better than the other models, and is able to provide an accurate prediction for the temperature dependent relaxation behavior, from the Arrhenius behavior below, to the Williams-Landel-Ferry behavior above T SW. © 2013 IOP Publishing Ltd. Source


Lu H.,Harbin Institute of Technology | Huang W.M.,Nanyang Technological University
Smart Materials and Structures | Year: 2013

We present a phenomenological approach to study the viscoelastic transition and working mechanism of the chemo-responsive shape memory effect (SME) in amorphous shape memory polymers (SMPs). Both the copolymerization viscosity model and Doolittle equation are initially applied to quantitatively identify the influential factors behind the chemo-responsive SME in the SMPs exposure to a right solvent. After this, the Williams-Landel-Ferry (WLF) equation is employed to couple the viscosity (η), time-temperature shift factor (ατ) and glass transition temperature (Tg) in amorphous polymers. By means of combining the WLF and Arrhenius equations together, the inductively decreased transition temperature is confirmed as the driving force for the chemo-responsive SME. Finally, a phenomenological viscoelastic model is proposed and then verified by the available experimental data reported in the literature and then compared with the simulation results of a semi-empirical model. This phenomenological model is expected to provide a powerful simulation tool for theoretical prediction and experimental substantiation of the chemo-responsive SME in amorphous SMPs by viscoelastic transition. © 2013 IOP Publishing Ltd. Source


Lau R.Y.K.,University of Hong Kong | Xia Y.,Tsinghua University | Ye Y.,Harbin Institute of Technology
IEEE Computational Intelligence Magazine | Year: 2014

Abstract-There has been a rapid growth in the number of cybercr imes that cause tremendous financial loss to organizations. Recent studies reveal that cybercriminals tend to collaborate or even transact cyber-attack tools via the dark markets established in online social media. Accordingly, it presents unprecedented opportunities for researchers to tap into these underground cybercriminal communities to develop better insights about collaborative cybercrime activities so as to combat the ever increasing number of cybercrimes. The main contribution of this paper is the development of a novel weakly supervised cybercriminal network mining method to facilitate cybercrime forensics. In particular, the proposed method is underpinned by a probabilistic generative model enhanced by a novel context-sensitive Gibbs sampling algorithm. Evaluated based on two social media corpora, our experimental results reveal that the proposed method significantly outperforms the Latent Dirichlet Allocation (LDA) based method and the Support Vector Machine (SVM) based method by 5.23% and 16.62% in terms of Area Under the ROC Curve (AUC), respectively. It also achieves comparable performance as the state-of-the-art Partially Labeled Dirichlet Allocation (PLDA) method. To the best of our knowledge, this is the first successful research of applying a probabilistic generative model to mine cybercriminal networks from online social media. © 2014 IEEE. Source


Sun Z.,Fudan University | Wang H.,Harbin Institute of Technology | Wang H.,Microsoft | Shao B.,Microsoft | Li J.,Harbin Institute of Technology
Proceedings of the VLDB Endowment | Year: 2012

The ability to handle large scale graph data is crucial to an increasing number of applications. Much work has been dedicated to supporting basic graph operations such as subgraph matching, reachability, regular expression matching, etc. In many cases, graph indices are employed to speed up query processing. Typically, most indices require either super-linear indexing time or super-linear indexing space. Unfortunately, for very large graphs, super-linear approaches are almost always infeasible. In this paper, we study the problem of subgraph matching on billion-node graphs. We present a novel algorithm that supports efficient subgraph matching for graphs deployed on a distributed memory store. Instead of relying on super-linear indices, we use efficient graph exploration and massive parallel computing for query processing. Our experimental results demonstrate the feasibility of performing subgraph matching on web-scale graph data. © 2012 VLDB Endowment. Source


Zhao B.,Georgia Institute of Technology | Zhao J.M.,Georgia Institute of Technology | Zhao J.M.,Harbin Institute of Technology | Zhang Z.M.,Georgia Institute of Technology
Applied Physics Letters | Year: 2014

Graphene has been demonstrated as a good candidate for ultrafast optoelectronic devices. However, graphene is essentially transparent in the visible and near infrared with an absorptivity of 2.3%, which has largely limited its application in photon detection. This Letter demonstrates that the absorptance in a monatomic graphene layer can be greatly enhanced to nearly 70%, thanks to the localized strong electric field resulting from magnetic resonances in deep metal gratings. Furthermore, the resonance frequency is essentially not affected by the additional graphene layer. The method presented here may benefit the design of next-generation graphene-based optical and optoelectronic devices. © 2014 AIP Publishing LLC. Source


Qiao W.-Q.,Harbin Institute of Technology
Chemical Research in Chinese Universities | Year: 2012

A new series of near infrared(NIR) electrochromic anthraquinone imides containing a triphenylamine moiety as an electron donor was synthesized and their electrochemical and spectroelectrochemical behavior were investigated. The results show that the new anthraquinone imides are redox active which can be reduced electrochemically from the neutral state to the radical anion form that absorbs in a range of 700-1200 nm. Source


We study in this paper the three-axis magnetic attitude control of small spacecraft by considering the actuator saturation. By noticing that the linearized dynamics is a neutrally stable linear periodic system, a general problem of global stabilization of linear periodic systems with bounded feedback is formulated and solved by both state feedback and observer based output feedback. Explicit saturated linear feedback control laws are established by using solutions to some Lyapunov differential equations associated with the open-loop systems and global stability of the closed-loop system is proved by constructing an explicit Lyapunov function. To apply the theoretical results on the three-axis magnetic attitude control systems, necessary and sufficient conditions are established to guarantee that the linearized open-loop system is neutrally stable and explicit solutions to the associated Lyapunov equations are obtained consequently. The controllers for the three-axis magnetic attitude control systems are then given in closed-form. Simulations show the effectiveness of the proposed approach. © 2015 Elsevier Ltd. Source


Bai F.-B.,Harbin Institute of Technology
Gongcheng Lixue/Engineering Mechanics | Year: 2015

In deep foundation pit, soil wedge is assumed in an active state of limit equilibrium under the gravity effect of side wall. Anchors or other supports produce pressure to the wedge slip surface, thus intergranular stress, shear stress, friction and shear strength prevent the slope sliding. When digging deeper, soil can still maintain the state described above. Theoretical derivation was carried out according to this concept and More-Coulomb strength theory: the relationship between shear stress strength increment and the principal stress increment was obtained. And accordingly, the formulas of the maximum and minor principal stress increment and the internal stress distribution of soil wedge were obtained. The analytic formula for pit wall vertical depth with the lateral pressure and the foundation pit top load was established, which is suitable for generalized nonlinear strength criterion in soil test, and stress circle with shear stress envelope was drawn. Nonlinear internal force analysis method was provided. Compared with the current earth pressure calculation model, this method is material saving and has obvious economic benefit. ©, 2015, Tsinghua University. All right reserved. Source


Group substations have dominated district heating (DH) systems in China so far. In order to explore the applicability of building substations to DH systems in China, the case study has been carried out in Ulanhot, by comprehensively comparing the energy consumptions and costs of group and building substation systems. Firstly, building simulation is used to help design the substations and DH networks, and analyze the operation considering variable flow and holiday control, which revealed the energy-saving advantages and flexibility of the building substation system. Secondly, the structure of the outdoor network in the building substation system is redesigned using the results of building simulation. Then, the total energy consumption of the group and building substation systems, including heating energy, pumping energy, and heat loss, is simulated and compared, considering the regulation of the water temperature. According to the operation data of the group substation system in the last two heating periods, the relative error of the simulated total energy was -6.8%. Finally, the annual cost method is employed for the economic analysis, which shows the superiority of the building substation system with annual cost reductions ranging between 5.7 and 5.9% for a lifetime range of 10-30 years. © 2015. Source


Zhao Y.,Harbin Institute of Technology | Zhao B.,CAS Institute of Biophysics
Frontiers in Bioscience - Elite | Year: 2012

Alzheimer's disease (AD) is the most common neurodegenerative disease that causes dementia in the elderly. As the aging population increases, the prevalence of AD has increased remarkably worldwide and AD has become one of the leading causes of disability and death among the elderly. A number of drugs have been approved for the treatment of AD; however, they produce only modest benefits and have a wide range of side effects. Therefore, extensive studies are underway to identify effective drugs that are free of undesirable side effects. As accumulating evidences have implicated oxidative stress in the initiation and progression of AD, the potential of using nature antioxidants for prevention and treatment of AD has attracted considerable attention. The present review discusses the involvement of oxidative stress in the pathogenesis of AD and the neuroprotective effects of natural antioxidants, such as Ginkgo biloba flavonoids, soybean isoflavones, theanine and nicotine in cell culture and AD transgenic animal models, specifically, their inhibition on Abeta-induced neurotoxicity and the underlined molecular mechanisms. Source


Mi J.-X.,Harbin Institute of Technology | Mi J.-X.,A+ Network | Liu J.-X.,Qufu Normal University
PLoS ONE | Year: 2013

The sparse representation-based classification (SRC) has been proven to be a robust face recognition method. However, its computational complexity is very high due to solving a complex l1-minimization problem. To improve the calculation efficiency, we propose a novel face recognition method, called sparse representation-based classification on k-nearest subspace (SRC-KNS). Our method first exploits the distance between the test image and the subspace of each individual class to determine the k nearest subspaces and then performs SRC on the k selected classes. Actually, SRC-KNS is able to reduce the scale of the sparse representation problem greatly and the computation to determine the k nearest subspaces is quite simple. Therefore, SRC-KNS has a much lower computational complexity than the original SRC. In order to well recognize the occluded face images, we propose the modular SRC-KNS. For this modular method, face images are partitioned into a number of blocks first and then we propose an indicator to remove the contaminated blocks and choose the k nearest subspaces. Finally, SRC is used to classify the occluded test sample in the new feature space. Compared to the approach used in the original SRC work, our modular SRC-KNS can greatly reduce the computational load. A number of face recognition experiments show that our methods have five times speed-up at least compared to the original SRC, while achieving comparable or even better recognition rates. © 2013 Mi, Liu. Source


Kar S.,Harbin Institute of Technology
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

In the present study, we investigate the effect of Debye-Hückel potentials on the frequency-dependent dipole polarizability of the helium atom using highly correlated wave functions within the framework of the pseudostate summation technique. The dynamic dipole polarizability of He (1s2 1S) as a function of the scaled number density of the plasma electrons for arbitrary plasma temperature is presented. Screening effects on the resonance frequencies are also presented. In a free-atomic system, our calculated results are in agreement with the available theoretical and experimental predictions. © 2012 American Physical Society. Source


Kar S.,Harbin Institute of Technology | Ho Y.K.,Academia Sinica, Taiwan
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

We have searched for S-wave shape resonances in the Ps - system. The calculations are carried out in the framework of the complex-coordinate rotation method using both Hylleraas-type wave functions involving powers of interparticle coordinates, and the exponential correlated wave functions. We have located an S-wave shape resonance lying above the Ps (N = 2) threshold. By changing the mass of the positively charged particle from one unit of the electron mass to infinitely heavy, we have traced this resonance pole from Ps - to H -. Results for the shape resonance in H - are comparable with the available results in the literature. © 2012 American Physical Society. Source


Wu L.,Harbin Institute of Technology
International Journal of Engineering Science | Year: 2010

A new method is developed to derive the bounds of the effective thermal conductivity of composites with ellipsoidal inclusions. The transition layer for each ellipsoidal inclusion is introduced to make the trial temperature field for the upper bound and the trial heat flux field for the lower bound satisfy the continuous interface conditions which are absolutely necessary for the application of variational principles. According to the principles of minimum potential energy and minimum complementary energy, the bounds of the effective thermal conductivity of composites with ellipsoidal inclusions are rigorously derived. The effects of the distribution and geometric parameters of ellipsoidal inclusions on the bounds of the effective thermal conductivity of composites are analyzed. It should be shown that the present method is simple and needs not calculate the complex integrals of multi-point correlation functions. Meanwhile, the present method provides a powerful way to bound the effective thermal conductivity of composites, which can be developed to obtain a series of bounds by taking different trial temperature and heat flux fields. In addition, the present upper and lower bounds still are finite when the thermal conductivity of ellipsoidal inclusions tends to ∞ and 0, respectively. © 2009 Elsevier Ltd. All rights reserved. Source


Chang Y.,University of Florida | Ries R.J.,University of Florida | Wang Y.,Harbin Institute of Technology
Energy Policy | Year: 2011

With rapid social development and large-scale construction of infrastructure in China, construction projects have become one of the driving forces for the national economy, whose energy consumption, environmental emissions, and social impacts are significant. To completely understand the role of construction projects in Chinese society, this study developed input-output life-cycle assessment models based on 2002, 2005, and 2007 economic benchmarks. Inventory indicators included 10 types of energy, 7 kinds of environmental emissions, and 7 kinds of social impacts. Results show that embodied energy of construction projects in China accounts for 25-30% of total energy consumption; embodied SO 2 emissions are being controlled, and the intensities of embodied NO x and CO 2 have been reduced. However, given that the construction sector related employment is 17% of the total employment in China, the accidents and fatalities related to the construction sector are significant and represent approximately 50% of the national total. The embodied human and capital investments in science and technology (ST) increased from 2002 to 2007. The embodied full time equivalent (FTE) of each ST person also increased while the personal ST funding and intramural expenditures decreased. This might result from the time lag between RD activities and large-scale implementation. © 2011. Source


Zhan K.,China University of Petroleum - East China | Hou C.,Harbin Institute of Technology
Optics Express | Year: 2014

We study theoretically surface lattice solitons driven by quadratic electro-optic effect at the interface between an optical lattice and diffusive nonlinear media with self-focusing and self-defocusing saturable nonlinearity. Surface solitons originating from self-focusing nonlinearity can be formed in the semi-infinite gap, and are stable in whole domain of their existence. In the case of self-defocusing nonlinearity, both surface gap and twisted solitons are predicted in first gap. We discover that surface gap solitons can propagate stably in whole existence domain except for an extremely narrow region close to the Bloch band, and twisted solitons are linearly unstable in the entire existence domain. © 2014 Optical Society of America. Source


Wu L.,Harbin Institute of Technology
International Journal of Engineering Science | Year: 2010

A new model is developed to bound the effective thermal conductivity of composites with thermal contact resistance between spherical inclusions and matrix. To construct the trial temperature and heat flux fields which satisfy the necessary interface conditions, the transition layer for each spherical inclusion is introduced. For the upper bound, the trial temperature field needs to satisfy the thermal contact resistance conditions between spherical inclusions and transition layers and the continuous interface conditions between transition layers and remnant matrix. For the lower bound, the trial heat flux field needs to satisfy the continuous interface conditions between different regions. It should be pointed out that the continuous interface conditions mentioned above are absolutely necessary for the application of variational principles, and the thermal contact resistance conditions between spherical inclusions and transition layers are suggested by the author. According to the principles of minimum potential energy and minimum complementary energy, the bounds of the effective thermal conductivity of composites with imperfect interfaces are rigorously derived. The effects of the size and distribution of spherical inclusions on the bounds of the effective thermal conductivity of composites are analyzed. It should be shown that the present method is simple and does not need to calculate the complex integrals of multi-point correlation functions. Meanwhile, the present method provides an entirely different way to bound the effective thermal conductivity of composites with imperfect interface, which can be developed to obtain a series of bounds by taking different trial temperature and heat flux fields. In addition, the present upper and lower bounds are finite when the thermal conductivity of spherical inclusions tends to ∞ and 0, respectively. © 2010 Elsevier Ltd. All rights reserved. Source


Chen J.-X.,Northeastern University China | Zhu Z.-L.,Northeastern University China | Liu Z.,Harbin Institute of Technology | Fu C.,Northeastern University China | And 2 more authors.
Optics Express | Year: 2014

Recently, a number of double-image cryptosystems have been developed. However, there are notable security performance differences between the two encryption channels in these algorithms. This weakness downgrades the security level and practicability of these cryptosystems, as the cryptosystems cannot guarantee all the input images be transmitted in the channel with higher security level. In this paper, we propose a novel double-image encryption scheme based on cross-image pixel scrambling in gyrator domains. The two input images are firstly shuffled by the proposed cross-image pixel scrambling approach, which can well balance the pixel distribution across the input images. The two scrambled images will be encoded into the real and imaginary parts of a complex function, and then converted into gyrator domains. An iterative architecture is designed to enhance the security level of the cryptosystem, and the cross-image pixel scrambling operation is performed to the real and imaginary parts of the generated complex encrypted data in each round. Numerical simulation results prove that a satisfactory and balanced security performance can be achieved in both channels. © 2014 Optical Society of America. Source


Lo S.S.,University of Notre Dame | Shi H.Y.,University of Notre Dame | Shi H.Y.,Harbin Institute of Technology | Huang L.,University of Notre Dame | Hartland G.V.,University of Notre Dame
Optics Letters | Year: 2013

Knowledge of how energy and charge carriers move in nanoscale systems is essential for engineering efficient devices. In this Letter, we demonstrate a technique to directly image dynamics in nanostructures based on laser scanning transient absorption microscopy, which provides near diffraction-limited spatial resolution and ultrafast time resolution. The capabilities of the technique are demonstrated by experiments on propagating surface plasmon polariton modes of Au nanowires, although these measurements can be used to study a variety of fluorescent and nonfluorescent systems. © 2013 Optical Society of America. Source


Zhao X.,Bohai University | Zhao X.,University of Hong Kong | Yin S.,Harbin Institute of Technology | Li H.,Bohai University | Niu B.,Bohai University
IEEE Transactions on Automatic Control | Year: 2015

In this technical note, the problem of switching stabilization for slowly switched linear systems is investigated. In particular, the considered systems can be composed of all unstable subsystems. Based on the invariant subspace theory, the switching signal with mode-dependent average dwell time (MDADT) property is designed to exponentially stabilize the underlying system. Furthermore, sufficient condition of stabilization for switched systems with all stable subsystems under MDADT switching is also given. The correctness and effectiveness of the proposed approaches are illustrated by a numerical example. © 2014 IEEE. Source


Chen Y.-H.,Fuzhou University | Xia Y.,Fuzhou University | Chen Q.-Q.,Fuzhou University | Song J.,Harbin Institute of Technology
Laser Physics Letters | Year: 2014

In this letter, we study the fast and noise-resistant population transfer, quantum entangled states' preparation and quantum entangled states' transition by constructing shortcuts to adiabatic passage (STAP) for multiparticles based on the approach of 'Lewis-Riesenfeld invariants' in a distant cavity quantum electronic dynamics (QED) system. Numerical simulation demonstrates that all of the schemes are fast and robust against the decoherence caused by atomic spontaneous emission and photon leakage. Moreover, it is not only the total operation time but also the robustness in each scheme against decoherence that is irrelevant to the number of qubits. This might lead to a useful step toward realizing fast and noise-resistant quantum information processing in current technology. © 2014 Astro Ltd. Source


Zhao X.,Bohai University | Zhao X.,China University of Petroleum - East China | Zhang L.,Harbin Institute of Technology | Shi P.,University of South Wales | And 2 more authors.
IEEE Transactions on Fuzzy Systems | Year: 2014

In this paper, novel stability conditions for Takagi-Sugeno (T-S) fuzzy systems are presented. The so-called nonquadratic membership-dependent Lyapunov function is first proposed, which is formulated in a higher order form of both the system states and the normalized membership functions than existing techniques in the literature. Then, new membership-dependent stability conditions are developed by the new Lyapunov function approach. It is shown that the conservativeness of the obtained criteria can be further reduced as the degree of the Lyapunov function increases. Two numerical examples are given to demonstrate the effectiveness and less conservativeness of the obtained theoretical results. © 1993-2012 IEEE. Source


Yang R.,Shandong University | Liu G.-P.,University of South Wales | Liu G.-P.,Harbin Institute of Technology | Shi P.,Victoria University of Melbourne | And 3 more authors.
IEEE Transactions on Industrial Electronics | Year: 2014

This paper studies the problem of predictive output feedback control for networked control systems (NCSs) with random communication delays. A networked-predictive-control scheme is employed to compensate for the network-induced delay. Furthermore, the time-varying predictive controller with mixed random delays for networked systems is introduced. Then, the system is formulated as a Markovian jump system. New techniques are presented to deal with the distributed delay in the discrete-time domain. Based on the analysis of closed-loop NCSs, the designed predictive time-varying output feedback controller can guarantee system stability. Simulation example demonstrates the compensation for random communication delays and data loss in networked systems using the proposed predictive scheme. © 1982-2012 IEEE. Source


Chang Y.,University of Florida | Ries R.J.,University of Florida | Wang Y.,Harbin Institute of Technology
Energy Policy | Year: 2013

In the context of rapid urbanization and new construction in rural China, residential building energy consumption has the potential to increase with the expected increase in demand. A process-based hybrid life-cycle assessment model is used to quantify the life-cycle energy use for both urban and rural residential buildings in China and determine the energy use characteristics of each life cycle phase. An input-output model for the pre-use phases is based on 2007 Chinese economic benchmark data. A process-based life-cycle assessment model for estimating the operation and demolition phases uses historical energy-intensity data. Results show that operation energy in both urban and rural residential buildings is dominant and varies from 75% to 86% of life cycle energy respectively. Gaps in living standards as well as differences in building structure and materials result in a life-cycle energy intensity of urban residential buildings that is 20% higher than that of rural residential buildings. The life-cycle energy of urban residential buildings is most sensitive to the reduction of operational energy intensity excluding heating energy which depends on both the occupants' energy-saving behavior as well as the performance of the building itself. © 2013 Elsevier Ltd. Source


Tong X.J.,Harbin Institute of Technology
Imaging Science Journal | Year: 2012

In order to solve the problem of short cycle and low precision of one-dimensional (1D) chaotic function, the new compound two-dimensional chaotic function is presented by exploiting two 1D chaotic functions which are switched randomly. A new chaotic sequence generator is designed by the compound chaos and linear feedback shift register (LFSR). The random properties of compound chaotic functions and LFSR are also proved rigorously. The novel bilateral-diffusion image encryption algorithm and permutation algorithm are proposed based on the compound chaotic function and LFSR, which can produce more avalanche effect and larger key space. The entropy analysis, differential analysis, statistical analysis, cipher random analysis and cipher sensitivity analysis are introduced to test the security of new scheme. The results show that the novel image encryption method passes SP 800-22 standard tests and solves the problem of short cycle and low precision of 1D chaotic function. © RPS 2012. Source


Zhang B.,Harbin Institute of Technology
International Journal of Control, Automation and Systems | Year: 2011

Eigenstructure assignment for descriptor systems with proportional plus derivative state feedback is studied. Based on a simple complete explicit parametric solution to a group of recursive equations, a parametric approach for eigenstrucure assignment in descriptor systems via proportional plus derivative state feedback is proposed. The proposed approach possesses the following features: 1) it does not impose any condition on the closed-loop eigenvalues, simultaneously assigns arbitrary n finite and infinite eigenvalues to the closed-loop system and guarantees the closed-loop regularity; 2) it is simple and needs less computational work; 3) it gives general complete parametric expressions for the closed-loop eigenvectors, the proportional state feedback gain matrix and the derivative state feedback gain matrix. © 2011 Institute of Control, Robotics and Systems and The Korean Institute of Electrical Engineers and Springer-Verlag Berlin Heidelberg. Source


Zhang Y.,Tianjin University | Sun L.,Harbin Institute of Technology
IEEE Transactions on Industrial Electronics | Year: 2011

With regard to a five-level inverter comprising flying-capacitor asymmetric H-bridge, the impact on the capacitor voltage under conventional modulation approach is analyzed. Since it is sensitive to the fundamental period and the load current, it may introduce undesired low-order harmonics into the output voltage and may even break down the power switches due to the considerable fluctuation of the flying-capacitor voltage. Thus, this paper proposes a novel pulsewidth-modulation scheme with the positive and negative cross carriers, which controls the flying-capacitor voltage by utilizing the redundant switching states of the output voltages. Three modes of precharging the flying capacitor without extra equipments are presented. Moreover, the capacitance of the flying capacitor and the switching frequency of the power switches can be chosen according to the allowable fluctuation of the flying-capacitor voltage and the load current. In order to remove the overlapping of the level layers, the optimization of the line-to-line voltage waveform is proposed to synthesize the reference vector with the nearest three-vector approach. The theory is supported by the experimental results from the prototype. © 2010 IEEE. Source


Xu W.,Pacific Northwest National Laboratory | Wang J.,Pacific Northwest National Laboratory | Wang J.,Shanghai JiaoTong University | Ding F.,Tianjin Institute of Power Sources | And 5 more authors.
Energy and Environmental Science | Year: 2014

Lithium (Li) metal is an ideal anode material for rechargeable batteries due to its extremely high theoretical specific capacity (3860 mA h g -1), low density (0.59 g cm-3) and the lowest negative electrochemical potential (-3.040 V vs. the standard hydrogen electrode). Unfortunately, uncontrollable dendritic Li growth and limited Coulombic efficiency during Li deposition/stripping inherent in these batteries have prevented their practical applications over the past 40 years. With the emergence of post-Li-ion batteries, safe and efficient operation of Li metal anodes has become an enabling technology which may determine the fate of several promising candidates for the next generation energy storage systems, including rechargeable Li-air batteries, Li-S batteries, and Li metal batteries which utilize intercalation compounds as cathodes. In this paper, various factors that affect the morphology and Coulombic efficiency of Li metal anodes have been analyzed. Technologies utilized to characterize the morphology of Li deposition and the results obtained by modelling of Li dendrite growth have also been reviewed. Finally, recent development and urgent need in this field are discussed. © The Royal Society of Chemistry. Source


Semi-globally input-to-state stable (ISS) control law is derived for flexible spacecraft attitude maneuvers in the presence of parameter uncertainties and external disturbances. The modified rodrigues parameters (MRP) are used as the kinematic variables since they are nonsingular for all possible rotations. This novel simple control is a proportional-plus-derivative (PD) type controller plus a sign function through a special Lyapunov function construction involving the sum of quadratic terms in the angular velocities, kinematic parameters, modal variables and the cross state weighting. A sufficient condition under which this nonlinear PD-type control law can render the system semi-globally input-to-state stable is provided such that the closed-loop system is robust with respect to any disturbance within a quantifiable restriction on the amplitude, as well as the set of initial conditions, if the control gains are designed appropriately. In addition to detailed derivations of the new controllers design and a rigorous sketch of all the associated stability and attitude convergence proofs, extensive simulation studies have been conducted to validate the design and the results are presented to highlight the ensuring closed-loop performance benefits when compared with the conventional control schemes. © 2009 Elsevier Ltd. All rights reserved. Source


Gao Z.,Zhejiang Normal University | Zhao X.,Harbin Institute of Technology
Optics and Lasers in Engineering | Year: 2012

In order to meet the needs of in-process measurement in mechanical engineering, we proposed a dynamic speckle method (DSM) for predicting the roughness of moving weak-scattering surfaces. The statistical properties of the dynamic speckle intensity produced by the rough surface were studied. A mathematical model of the recorded dynamic speckle image is built. Then a linear relationship was established between the surface height variance and the natural logarithm of a roughness characteristic parameter extracted from the dynamic speckle image. The theoretical derivations and computer simulations demonstrate that the present method is simple in measuring principle, insensitive to the surface correlation length and resistant to the machine tool vibration, which indicates that the DSM has the potential for in-process application. Finally, an experiment was given. © 2011 Elsevier Ltd. All rights reserved. Source


Lu H.,Harbin Institute of Technology | Liang F.,University of Central Florida | Gou J.,University of Central Florida
Soft Matter | Year: 2011

The present work studies the synergistic effect of self-assembly multi-walled carbon nanotube (MWCNT) nanopaper and sub-micro nickel nanostrand on the electrical properties and electro-active recovery behavior of shape memory polymer (SMP) nanocomposite. The combination of MWCNT nanopaper and nickel nanostrand is used to improve the electrical and thermal conductivities of the SMP nanocomposite. The electrical MWCNT nanopaper was coated on the surface to achieve the shape recovery of the SMP nanocomposite induced by electricity. Electromagnetic nickel nanostrands were blended with and, vertically aligned into the SMP resin in a magnetic field, to improve the thermal conductivity. The vertically aligned nickel nanostrands will facilitate the heat transfer from the nanopaper to the underlying SMP composite to accelerate the electrical actuation. Furthermore, they have little negative effect on recovery behavior, resulting in the nanocomposite having an approximately 100% recovery ratio undergoing cyclic deformation. © 2011 The Royal Society of Chemistry. Source


The fiber bundle shielding effect on the dynamic matrix cracking in fiber reinforced composite under dynamic loading was investigated using an optical caustics method. First, edge cracked epoxy beams, with a symmetrically positioned fiber bundle ahead of the crack tip, were preformed to simulate matrix crack shielding by the fiber bundle in fiber reinforced composites. Then, the effect of fiber bundle width on the dynamic matrix crack propagation behavior was analyzed using the caustics method, where the caustic spot shape, the dynamic stress intensity factor and crack propagation velocity were obtained to characterize the shielding effect of the fiber bundle. Finally, the shielding effect of a tilted fiber bundle with an angle of 30°on the dynamic matrix crack was analyzed using the optical caustics method, where the different fiber bundle width would cause different failure modes and failure mechanisms. © 2014 Elsevier Ltd. All rights reserved. Source


Huang Y.,Harbin Institute of Technology
Structural Health Monitoring 2011: Condition-Based Maintenance and Intelligent Structures - Proceedings of the 8th International Workshop on Structural Health Monitoring | Year: 2011

Signal compression is often important to reduce the cost of data transfer and storage for structural health monitoring (SHM) systems of civil structures. Compressive sensing is a novel data compressing method whereby one does not measure the entire signal directly but rather a set of related ("projected") measurements. The length of the required compressive-sensing measurements is typically much smaller than the original signal, therefore increasing the efficiency of data transfer and storage. Recently, a Bayesian formalism has also been employed for optimal compressive sensing, which adopts the ideas in the relevance vector machine (RVM) as a decompression tool. In this article, we study the robustness of the BCS method. We show that the usual RVM optimization algorithm lacks robustness when the number of measurements is a lot less than the length of the signals because it can produce sub-optimal signal representations; as a result, BCS is not robust when high compression efficiency is required. This induces a tradeoff between efficiently compressing data and accurately decompressing it. Based on a study of the robustness of the BCS method, diagnostic tools are proposed to investigate whether the compressed representation of the signal is optimal. The numerical results also are given to validate the proposed method. Source


Liu X.,China University of Mining and Technology | Peng G.,Harbin Institute of Technology | Hou Y.,China University of Mining and Technology
International Journal of Advanced Manufacturing Technology | Year: 2012

In order to realize automation and intelligence of product disassembly process in a virtual maintenance environment, an improved max-min ant system based methodology for product disassembly sequence planning was proposed. The feasibility graph for product disassembly process was defined and the mathematic model of product disassembly sequence planning problem was set up. Thus, the problem of product disassembly sequence planning was transformed into the problem of searching optimal path on a feasibility graph.Moreover, an improved max-min ant system based on the strategy of sorting elite ants was presented and the flowchart of the improved algorithm was designed. Finally, by simulation examples, the robustness and outperforming others of the improved algorithm were verified. © Springer-Verlag London Limited 2011. Source


Kar S.,Harbin Institute of Technology | Ho Y.K.,Academia Sinica, Taiwan
Computer Physics Communications | Year: 2011

We have investigated the Fe1,3 resonance states of positronium negative ion below the N=3, 4 and 5 Ps thresholds using highly correlated exponential wave functions. Resonance parameters (positions and widths) are extracted employing both the stabilization method and the complex-coordinate rotation method. In addition to many Feshbach resonances below the various Ps thresholds, we have identified two Fe1 shape resonances with one each lying above the N=3 and N=5 thresholds, respectively. We have also identified three Fe3 shape resonances with one lying above the N=3 threshold and two lying above N=4 threshold. The Fe1,3 shape resonances associated with N=3 Ps threshold and some other Feshbach resonances are reported for the first time in the literature. © 2010 Elsevier B.V. All rights reserved. Source


Cui J.,Harbin Institute of Technology
Neural Computing and Applications | Year: 2014

This paper employs both two-dimensional (2D) and three-dimensional (3D) features of palmprint for recognition. While 2D palmprint image contains plenty of texture information, 3D palmprint image contains the depth information of the palm surface. Using two different features, we can achieve higher recognition accuracy than using only one of them. In addition, we can improve the robustness. To recognize palmprints, we use two-phase test sample representation (TPTSR) which is proved to be successful in face recognition. Before TPTSR, we perform principal component analysis to extract global features from the 2D and 3D palmprint images. We make decision based on the fusion of 2D and 3D features matching scores. We perform experiments on the PolyU 2D + 3D palmprint database which contains 8,000 samples and achieve satisfying recognition performance. © 2012 Springer-Verlag London. Source


Yan Z.,Harbin Institute of Technology
IEEE Transactions on Automatic Control | Year: 2011

The descriptor system Eẋ=Ax+Gu+Hv with external disturbance v is considered. To characterize the possibility to cancel the impulses produced by external disturbance v through using control u, the concept of disturbance impulse controllability is introduced. © 2006 IEEE. Source


Kuang M.,China Jiliang University | Li Z.,Harbin Institute of Technology
Energy | Year: 2014

Low-volatile fuels such as anthracite and lean coal are widely used in power generators throughout the world. In comparison with tangential-fired and wall-arranged furnaces, down-fired boilers are thought to be more suitable for firing anthracite and lean coal. Currently, down-fired boilers are widely in service and have developed rapidly in China over the past 20 years. In this paper, a comprehensive review of investigations into the gas/particle flow, combustion and NOx emission characteristics within various types of down-fired boilers is presented. The published work disclosed that down-fired boilers suffered similarly from various problems such as late coal ignition, poor combustion stability, low burnout (carbon in fly ash typically in the range 7-15%), heavy slagging, high NOx emissions (typically in the range 1100-2100mg/m3 at 6% O2), and asymmetric combustion. Again, the causes of these problems and various solutions in dealing with them were introduced in turn. Although causes of these problems are complicated, the reported deficiencies such as the premature mixing between high-speed secondary air and low-speed fuel-rich coal/air flow, short coal/air flow penetration depth, downward coal/air flow washing over walls, shallow air-staging conditions, and asymmetric flow-field formation contribute great efforts to develop these problems. To summarize experiences and the lessons in those reported solutions, a series of suggestions for organizing reasonable combustion in down-fired furnaces have been provided so as to achieve timely ignition, symmetric and stable combustion, weak slagging, good burnout, and low NOx emissions. © 2014 Elsevier Ltd. Source


Chen D.,North China Electrical Power University | Hu Q.,Harbin Institute of Technology | Yang Y.,North China Electrical Power University
Information Sciences | Year: 2011

Fuzzy rough sets are considered as an effective tool to deal with uncertainty in data analysis, and fuzzy similarity relations are used in fuzzy rough sets to calculate similarity between objects. On the other hand in kernel tricks, a kernel maps data into a higher dimensional feature space where the resulting structure of the learning task is linearly separable, while the kernel is the inner product of this feature space and can also be viewed as a similarity function. It has been reported there is an overlap between family of kernels and collection of fuzzy similarity relations. This fact motivates the idea in this paper to use some kernels as fuzzy similarity relations and develop kernel based fuzzy rough sets. First, we consider Gaussian kernel and propose Gaussian kernel based fuzzy rough sets. Second we introduce parameterized attribute reduction with the derived model of fuzzy rough sets. Structures of attribute reduction are investigated and an algorithm with discernibility matrix to find all reducts is developed. Finally, a heuristic algorithm is designed to compute reducts with Gaussian kernel fuzzy rough sets. Several experiments are provided to demonstrate the effectiveness of the idea. © 2011 Elsevier Inc. All rights reserved. Source


Song F.,CAS Institute of Mechanics | Meng S.,Harbin Institute of Technology | Xu X.,CAS Institute of Mechanics | Shao Y.,CAS Institute of Mechanics
Physical Review Letters | Year: 2010

We propose here a new method to make ceramics insensitive to thermal shock up to their melting temperature. In this method the surface of ceramics was biomimetically roughened into nanofinned surface that creates a thin air layer enveloping the surface of the ceramics during quenching. This air layer increases the heat transfer resistance of the surface of the ceramics by about 10000 times so that the strong thermal gradient and stresses produced by the steep temperature difference in thermal shock did not occur both on the actual surface and in the interior of the ceramics. This method effectively extends the applications of existing ceramics in the extreme thermal environments. © 2010 The American Physical Society. Source


Little A.G.,University of Sydney | Kunisue T.,New York State Department of Health | Kannan K.,New York State Department of Health | Kannan K.,Harbin Institute of Technology | Seebacher F.,University of Sydney
BMC Biology | Year: 2013

Background: Thyroid hormone (TH) is best known for its role in development in animals, and for its control of metabolic heat production (thermogenesis) during cold acclimation in mammals. It is unknown whether the regulatory role of TH in thermogenesis is derived in mammals, or whether TH also mediates thermal responses in earlier vertebrates. Ectothermic vertebrates show complex responses to temperature variation, but the mechanisms mediating these are poorly understood. The molecular mechanisms underpinning TH action are very similar across vertebrates, suggesting that TH may also regulate thermal responses in ectotherms. We therefore aimed to determine whether TH regulates thermal acclimation in the zebrafish (Danio rerio). We induced hypothyroidism, followed by supplementation with 3,5-diiodothyronine (T2) or 3,5,3′-triiodothyronine (T3) in zebrafish exposed to different chronic temperatures. We measured whole-animal responses (swimming performance and metabolic rates), tissue-specific regulatory enzyme activities, gene expression, and free levels of T2 and T3.Results: We found that both T3 and the lesser-known T2, regulate thermal acclimation in an ectotherm. To our knowledge, this is the first such study to show this. Hypothyroid treatment impaired performance measures in cold-acclimated but not warm-acclimated individuals, whereas supplementation with both TH metabolites restored performance. TH could either induce or repress responses, depending on the actual temperature and thermal history of the animal.Conclusions: The low sensitivity to TH at warm temperatures could mean that increasing temperatures (that is, global warming) will reduce the capacity of animals to regulate their physiologies to match demands. We suggest that the properties that underlie the role of TH in thermal acclimation (temperature sensitivity and metabolic control) may have predisposed this hormone for a regulatory role in the evolution of endothermy. © 2013 Little et al.; licensee BioMed Central Ltd. Source


Chen G.,State University of New York at Buffalo | Chen G.,Harbin Institute of Technology | Agren H.,KTH Royal Institute of Technology | Ohulchanskyy T.Y.,State University of New York at Buffalo | And 2 more authors.
Chemical Society Reviews | Year: 2015

Light upconverting nanostructures employing lanthanide ions constitute an emerging research field recognized with wide ramifications and impact in many areas ranging from healthcare, to energy and, to security. The core-shell design of these nanostructures allows us to deliberately introduce a hierarchy of electronic energy states, thus providing unprecedented opportunities to manipulate the electronic excitation, energy transfer and upconverted emissions. The core-shell morphology also causes the suppression of quenching mechanisms to produce efficient upconversion emission for biophotonic and photonic applications. Using hierarchical architect, whereby each shell layer can be defined to have a specific feature, the electronic structure as well as the physiochemical structure of the upconverting nanomaterials can be tuned to couple other electronic states on the surface such as excitations of organic dye molecules or localized surface plasmons from metallic nanostructures, or to introduce a broad range of imaging or therapeutic modalities into a single conduct. In this review, we summarize the key aspects of nanophotonic control of the light upconverting nanoparticles through governed design and preparation of hierarchical shells in the core-shell nanostructures, and review their emerging applications in the biomedical field, solar energy conversion, as well as security encoding. This journal is © The Royal Society of Chemistry. Source


Chen Y.,Beijing Computational Science Research Center | Zhang B.,Harbin Institute of Technology
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

We investigate the emission times of high-order harmonics from the asymmetric molecule HeH2 + exposed to intense laser fields numerically and analytically. We show that for each laser cycle, the emission times of harmonics follow two characteristic electron trajectories. The first one matches the prediction of the general ground-state-based quantum orbital theory (GSB-QOT), as the second one differs significantly from the GSB-QOT. We show that the excited state plays an important role in this difference. As a result, the emission times of harmonics can be used as a tool to monitor the dynamics of excited states of the asymmetry molecule in strong laser fields. © 2012 American Physical Society. Source


Hu J.,Harbin Institute of Technology | Wang Z.,Brunel University | Niu Y.,East China University of Science and Technology | Stergioulas L.K.,Brunel University
International Journal of Robust and Nonlinear Control | Year: 2012

In this paper, the H ∞ sliding mode observer (SMO) design problem is investigated for a class of nonlinear discrete time-delay systems. The nonlinear descriptions quantify the maximum possible derivations from a linear model, and the system states are allowed to be immeasurable. Attention is focused on the design of a discrete-time SMO such that the asymptotic stability as well as the H ∞ performance requirement of the error dynamics can be guaranteed in the presence of nonlinearities, time delay and external disturbances. Firstly, a discrete-time discontinuous switched term is proposed to make sure that the reaching condition holds. Then, by constructing a new Lyapunov-Krasovskii functional based on the idea of 'delay fractioning' and by introducing some appropriate free-weighting matrices, a sufficient condition is established to guarantee the desired performance of the error dynamics in the specified sliding mode surface by solving a minimization problem. Finally, an illustrative example is given to show the effectiveness of the designed SMO design scheme. Copyright © 2011 John Wiley & Sons, Ltd. Copyright © 2011 John Wiley & Sons, Ltd. Source


Liu Y.-T.,Tsinghua University | Zhu X.-D.,Harbin Institute of Technology | Duan Z.-Q.,Tsinghua University | Xie X.-M.,Tsinghua University
Chemical Communications | Year: 2013

A flexible and robust MoS2-graphene hybrid paper with an excellent lithium storage capacity is fabricated through cross-linking by a polymer ligand, PEO, and shows potential for the development of high-performance film anodes. © 2013 The Royal Society of Chemistry. Source


Zeng W.-J.,City University of Hong Kong | So H.C.,City University of Hong Kong | Huang L.,Harbin Institute of Technology
IEEE Transactions on Signal Processing | Year: 2013

A family of algorithms, named ℓ p-MUSIC, for direction-of-arrival (DOA) estimation in impulsive noise is proposed. The ℓ p-MUSIC estimator adopts the ℓ p-norm (1leq p< 2) of the residual fitting error matrix as the objective function for subspace decomposition, rather than the Frobenius norm that is used in the conventional MUSIC method. Although the matrix ℓ p -norm minimization based subspace decomposition will lead to a nonconvex optimization problem, two iterative algorithms are designed for achieving efficient solutions. The first algorithm is the iteratively reweighted singular value decomposition (IR-SVD), where the SVD of a reweighted data matrix is performed in each iteration. The second algorithm solves the nonconvex matrix ℓ p-norm minimization by alternating convex optimization. Two complex-valued Newton's methods with optimal step size in each iteration are devised to solve the resulting convex problem. The convergence of the iterative procedure is also proved. Numerical results verify that the ℓ p-MUSIC methodology outperforms the standard MUSIC scheme and several existing outlier-resistant DOA estimation approaches in terms of resolution capability and estimation accuracy. © 1991-2012 IEEE. Source


Ma Y.,Rice University | Ma Y.,Harbin Institute of Technology | Lewicki R.,Rice University | Razeghi M.,Northwestern University | Tittel F.K.,Rice University
Optics Express | Year: 2013

An ultra-sensitive and selective quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor platform was demonstrated for detection of carbon monoxide (CO) and nitrous oxide (N2O). This sensor used a stateof-the art 4.61 μm high power, continuous wave (CW), distributed feedback quantum cascade laser (DFB-QCL) operating at 10°C as the excitation source. For the R(6) CO absorption line, located at 2169.2 cm-1, a minimum detection limit (MDL) of 1.5 parts per billion by volume (ppbv) at atmospheric pressure was achieved with a 1 sec acquisition time and the addition of 2.6% water vapor concentration in the analyzed gas mixture. For the N2O detection, a MDL of 23 ppbv was obtained at an optimum gas pressure of 100 Torr and with the same water vapor content of 2.6%. In both cases the presence of water vapor increases the detected CO and N2O QEPAS signal levels as a result of enhancing the vibrational-translational relaxation rate of both target gases. Allan deviation analyses were performed to investigate the long term performance of the CO and N2O QEPAS sensor systems. For the optimum data acquisition time of 500 sec a MDL of 340 pptv and 4 ppbv was obtained for CO and N2O detection, respectively. To demonstrate reliable and robust operation of the QEPAS sensor a continuous monitoring of atmospheric CO and N2O concentration levels for a period of 5 hours were performed. © 2013 Optical Society of America. Source


Xu H.,Harbin Institute of Technology | Spitler J.D.,Oklahoma State University
Renewable Energy | Year: 2014

Predicting ground temperature is an important part of the analysis of geothermal resources assessment and use. Thus, we develop and validate one-dimensional numerical model for heat and mass transfer in partially frozen soils. The model is implemented in HVACSIM Plus and used to simulate the thermal regime of soil profile. In addition to modeling heat conduction, model variations also includes moisture transfer, snow accumulation and melting, and soil freezing and thawing. The results are compared against experimental measurements of ground temperature for three locations in Montana, USA. The differences between simulated depth temperature with and without snow cover and freezing and thawing of soil reveal that ground temperatures are predominantly influenced by these two factors. Considering moisture transfer slightly improves temperature predictions, although it increases computational time by one order of magnitude. To balance computational efficiency with prediction accuracy, we propose an equivalent moisture content of 40-60% saturation in predicting ground temperature. © 2014 Elsevier Ltd. Source


Huang L.,Harbin Institute of Technology | So H.C.,City University of Hong Kong
IEEE Transactions on Signal Processing | Year: 2013

Numerous methodologies have been investigated for source enumeration in sample-starving environments. For those having their root in the framework of random matrix theory, the involved distribution of the sample eigenvalues is required. Instead of relying on the eigenvalue distribution, this work devises a linear shrinkage based minimum description length (LS-MDL) criterion by utilizing the identity covariance matrix structure of noise subspace components. With linear shrinkage and Gaussian assumption of the observations, an accurate estimator for the covariance matrix of the noise subspace components is derived. The eigenvalues obtained from the estimator turn out to be a linear function of the corresponding sample eigenvalues, enabling the LS-MDL criterion to accurately detect the source number without incurring significantly additional computational load. Furthermore, the strong consistency of the LS-MDL criterion for m,n\ura{} ∞ and m/n\ura{} c in (0,∞) is proved, where m and n are the antenna number and snapshot number, respectively. Simulation results are included for illustrating the effectiveness of the proposed criterion. © 1991-2012 IEEE. Source


Wu S.,Harbin Institute of Technology | Wu S.,McGill University | Rabbat M.G.,McGill University
IEEE Transactions on Signal Processing | Year: 2013

We study a general framework for broadcast gossip algorithms which use companion variables to solve the average consensus problem. Each node maintains an initial state and a companion variable. Iterative updates are performed asynchronously whereby one random node broadcasts its current state and companion variables and all other nodes receiving the broadcast update their state and companion variables. We provide conditions under which this scheme is guaranteed to converge to a consensus solution, where all nodes have the same limiting values, on any strongly connected directed graph. Under stronger conditions, which are reasonable when the underlying communication graph is undirected, we guarantee that the consensus value is equal to the average, both in expectation and in the mean-squared sense. Our analysis uses tools from non-negative matrix theory and perturbation theory. The perturbation results rely on a parameter being sufficiently small. We characterize the allowable upper bound as well as the optimal setting for the perturbation parameter as a function of the network topology, and this allows us to characterize the worst-case rate of convergence. Simulations illustrate that, in comparison to existing broadcast gossip algorithms, the approaches proposed in this paper have the advantage that they simultaneously can be guaranteed to converge to the average consensus and they converge in a small number of broadcasts. © 1991-2012 IEEE. Source


Kong F.-Y.,Nanjing University | Xu B.-Y.,Nanjing University | Du Y.,Harbin Institute of Technology | Xu J.-J.,Nanjing University | Chen H.-Y.,Nanjing University
Chemical Communications | Year: 2013

A branched electrode platform was proposed for label-free and reagentless simultaneous tumor markers detection based on different redox substrates. © 2013 The Royal Society of Chemistry. Source


Li Q.Y.,Shanghai JiaoTong University | Wang L.,Harbin Institute of Technology | Ju Y.L.,Shanghai JiaoTong University
Applied Energy | Year: 2011

A novel liquefaction and distillation process has been proposed and designed for the typical oxygen-bearing coal-bed methane (CBM), in which the impurities of the oxygen and nitrogen components are removed in the distillation column. The flammability limit theory combining with HYSYS simulation results are employed to analyze and calculate the flammability limits and the results indicate that no flammability hazard exists in the stages of compression, liquefaction and throttling. However, flammability hazard exists at the top the distillation column because the methane mole fraction decreases to the value below the upper flammability limit (UFL). The safety measures of initially removing oxygen content from the feed gas combining with the control of the bottom flowrate (flowrate of the liquid product at column bottom) are proposed to ensure the operation safety of the liquefaction process. The results reveal that the operation safety of the whole process can be guaranteed, together with high methane recovery rate and high purity of the liquid product. The applicability of the liquefaction process has also been analyzed in this paper. The simulation results can offer references for the separation of oxygen from CBM, the analysis of flammability limits and the safety measures for the whole process. © 2011 Elsevier Ltd. Source


Fang J.,Harbin Institute of Technology | Zhao X.-Q.,Memorial University of Newfoundland
Nonlinearity | Year: 2011

A sufficient and necessary condition for the existence of monotone travelling waves in the nonlocal Fisher-KPP equation is established, and the uniqueness of travelling wavefronts (up to translation) is also proved. © 2011 IOP Publishing Ltd & London Mathematical Society. Source


Kaloop M.R.,Mansoura University | Li H.,Harbin Institute of Technology
Measurement: Journal of the International Measurement Confederation | Year: 2011

This paper uses GPS monitoring system on the Yonghe Bridge. After a year from re-construction of this bridge, cracks were pronounced 48.2 m far from the beginning of the abutment. To analyze the movements of bridge tower, the current operational safety, the cause of bridge cracks and sensitivity of GPS signals, and its movements were observed under different stress factors such as wind speed, temperature change and traffic loads. The observed lateral, longitudinal of bridge's towers were studied. Two analytical methods namely; DWT and FT were used for the analysis of observation data. The analysis of test results indicates that: (1) The STFT is a significant step forward from the traditional FFT in terms of structural response analysis. (2) The sensitivity of GPS signals does not depend on the position of GPS antenna; and (3) the cracks of bridge deck bring out the frequency of the bridge tower movement transient characteristics. © 2011 Elsevier Ltd. All rights reserved. Source


Lu L.,University of Colorado at Boulder | Xing D.,Harbin Institute of Technology | Ren Z.J.,University of Colorado at Boulder
Bioresource Technology | Year: 2015

(Figure Presented). This study reveals the complex structure of bacterial and archaeal communities associated with a Canna indica plant microbial fuel cell (PMFC) and its electricity production. The PMFC produced a maximum current of 105 mA/m2 by utilizing rhizodeposits as the sole electron donor without any external nutrient or buffer supplements, which demonstrates the feasibility of PMFCs in practical oligotrophic conditions with low solution conductivity. The microbial diversity was significantly higher in the PMFC than non-plant controls or sediment-only controls, and pyrosequencing and clone library reveal that rhizodeposits conversion to current were carried out by syntrophic interactions between fermentative bacteria (e.g., Anaerolineaceae) and electrochemically active bacteria (e.g., Geobacter). Denitrifying bacteria and acetotrophic methanogens play a minor role in organics degradation, but abundant hydrogenotrophic methanogens and thermophilic archaea are likely main electron donor competitors. © 2015 Elsevier Ltd. Source


Liu J.,Harbin Institute of Technology | Zhou X.,Lanzhou University
Journal of Constructional Steel Research | Year: 2010

This paper presents an experimental and analytical study on the behavior of axially compressed tubed RC stub columns. Forty specimens including twenty circular tubed RC (STRC) and twenty square tubed RC (STRC) stub columns were tested to investigate the failure mode and axial load strength of tubed RC columns subjected to axial compression. The effect of diameter/width to thickness ratio of the tubes and compressive strength of concrete were also studied. The effect of height to diameter/width ratio of the separated tube in tubed RC columns was studied to investigate the effect of bond and friction between tube and concrete on the behavior of tubed RC columns. Elastic-plastic analysis on the steel tube was employed to study the mechanism of tubed RC stub columns subjected to axial compression. Equations for the prediction of the ultimate axial load strength of tubed RC stub columns were proposed and the results from prediction were compared with the test results. © 2009 Elsevier Ltd. All rights reserved. Source


Zhao J.,Harbin Institute of Technology | Yang L.,Carnegie Institution of Washington
Journal of Physical Chemistry C | Year: 2014

Indium selenide (In2Se3) could be used as the phase-change random access memory device and thermoelectric material. The high-pressure investigations are important to the applications on In 2Se3 and other A2B3-type materials. In this study, we performed the in situ angle-dispersive X-ray diffraction and Raman spectra experiments and the first-principle calculations on In 2Se3 under high pressure, and observed a series of structure phase transitions from experiments and metallized phenomena from calculations. In2Se3 transforms from the original rhombohedral structure (phase I) to a distorted monoclinic structure (phase II) and further to a Bi2Te3-type structure (phase III) at about 0.81 and 5.02 GPa, respectively. And then, phase III′ of In 2Se3 adopts a similar structure with phase III from about 20.6 GPa. At pressures above about 32.1 GPa, In2Se3 starts to crystallize into a defective Th3P4-type structure (phase IV). According to the first-principle calculations, the structural transitions in the compression process induce that In2Se3 transforms from an insulator in phase I, across a semimetal in phase II and III, to a novel metal in the body-centered cubic structure (phase IV). The pressure-induced structure and conducting evolution on In2Se 3 are helpful to understand the properties of other selenides upon compression. © 2014 American Chemical Society. Source


Dai G.-L.,Fujian University of Technology | Xia X.-L.,Harbin Institute of Technology | Hou G.-F.,Fujian University of Technology
Solar Energy | Year: 2014

To investigate the transmission performances of solar windows subjected to concentrated sunlight, an integrated sunlight transferring model was built, which was formed by a dish and a curved surface window. Considering the dish performances and the window materials, the transmissivity of the windows was predicted by the Monte Carlo ray-tracing method (MCRTM). The results show that the transmissivity of the quartz glass window is about 12.0% higher than that of the sapphire window because the refractive index and the absorption coefficient of the quartz glass is lower than that of the sapphire. For a combined dish and window system, the influences of the window geometries on the transmissivity are negligible. However, decreasing the slope errors and tracking errors of the dish is able to improve the transmission performances of the windows. © 2014 Elsevier Ltd. Source


Li X.,Soochow University of China | Zhan Y.,Harbin Institute of Technology
Applied Physics Letters | Year: 2013

Single-nanowire solar cells (SNSCs) in lying configuration can have external quantum efficiency (EQE) over 100% but always in narrowbands with EQE peaks slightly exceeding unit. We presented a rectangular gallium arsenide (GaAs) SNSC, which provides light absorption efficiency (Qabs) and EQE far beyond 100% for both transverse electric and magnetic illuminations, by optimally engineering the nanowires and introducing an advanced nanoshell design. Electromagnetic and carrier transport calculations show that Q abs and EQE peaks of the designed SNSCs can both be over 200% with averaged EQE ∼ 150% in most of the active spectral band of GaAs. © 2013 American Institute of Physics. Source


Lu H.,Harbin Institute of Technology
Journal of Applied Polymer Science | Year: 2013

In this study we analyzed the phase and state transitions of shape-memory polymers (SMPs)/solvent mixtures using the Flory-Huggins (FH) theory by extension of Vrentas and the Couchman-Karasz theory for glass transition, as well as Clausius-Clapeyron relation for melting transition. Using scaling relations of model parameters, we have obtained a theoretical prediction of state diagrams of the phase transition temperature and solvent-induced recovery in SMPs. The inductive decrease in transition temperature is identified as the driving force for the solvent-induced shape-memory effect in SMPs Consequently, the thermodynamics of the polymer solution and the relaxation theory were employed to characterize the dependencies of shape recovery time on the FH parameter and the ratio of the molar volume of solute to solvent. With the estimated model parameters, we constructed the state diagram for SMP, which provides a powerful tool for design and analysis of phase transition temperatures and solvent-induced recovery. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 Copyright © 2012 Wiley Periodicals, Inc. Source


Lu H.,Harbin Institute of Technology | Min Huang W.,Nanyang Technological University
Applied Physics Letters | Year: 2013

The present work studies the synergistic effect of self-assembled carboxylic acid-functionalized carbon nanotube (CNT) and carbon fiber on the electrical property and electro-activated recovery behavior of shape memory polymer (SMP) nanocomposites. The combination of CNT and carbon fiber results in improved electrical conductivity in the SMP nanocomposites. Carboxylic acid-functionalized CNTs are grafted onto the carbon fibers and then self-assembled by deposition to significantly enhance the reliability of the bonding between carbon fiber and SMP via van der Waals and covalent crosslink. Furthermore, the self-assembled carboxylic acid-functionalized CNTs and carbon fibers enable the SMP nanocomposites for Joule heating triggered shape recovery. © 2013 AIP Publishing LLC. Source


Xu Y.,Sun Yat Sen University | Li Z.,Harbin Institute of Technology
IEEE Transactions on Industrial Electronics | Year: 2015

A microgrid is a promising approach to provide clean, renewable, and reliable electricity by integrating various distributed generations and energy storage systems into power systems. However, highly intermittent renewable generations and various load demands pose new challenges to the optimal resource management in a microgrid. This paper proposes a fully distributed control strategy based on the consensus algorithm for the optimal resource management in an islanded microgrid. The proposed strategy is implemented through a multiagent system framework, which only requires information exchange among neighboring agents through a local network. The objective is achieved through a two-level control strategy. The upper control level is a consensus-based optimization algorithm that discovers the reference of optimal power generation or demand while maintaining the supply-demand balance. The lower control level is responsible for reference tracking of the associated component. Simulation results in the IEEE 14- and 162-bus systems are presented to demonstrate the effectiveness of the proposed control strategy. © 1982-2012 IEEE. Source


Tong X.-J.,Harbin Institute of Technology
Journal of Systems and Software | Year: 2012

Chaos may be degenerated because of the finite precision effect, hence the new compound two-dimensional chaotic function is presented by exploiting two one-dimensional chaotic functions which are switched randomly. A new chaotic sequence generator is designed by the compound chaos which is proved by Devaney's definition of chaos. The properties of dynamical compound chaotic functions and LFSR are also proved rigorously. A novel bilateral-diffusion image encryption algorithm is proposed based on dynamical compound chaotic function and LFSR, which can produce more avalanche effect and more large key space. The entropy analysis, differential analysis, statistical analysis, cipher random analysis, and cipher sensitivity analysis are introduced to test the security of new scheme. Many experiment results show that the novel image encryption method passes SP 800-22 and DIEHARD standard tests and solves the problem of short cycle and low precision of one-dimensional chaotic function. © 2011 Elsevier Inc. All rights reserved. Source


Ye Q.,Harbin Institute of Technology | Law R.,Hong Kong Polytechnic University | Gu B.,University of Texas at Austin | Chen W.,University of California at San Diego
Computers in Human Behavior | Year: 2011

The increasing use of web 2.0 applications has generated numerous online user reviews. Prior studies have revealed the influence of user-generated reviews on the sales of products such as CDs, books, and movies. However, the influence of online user-generated reviews in the tourism industry is still largely unknown both to tourism researchers and practitioners. To bridge this knowledge gap in tourism management, we conducted an empirical study to identify the impact of online user-generated reviews on business performance using data extracted from a major online travel agency in China. The empirical findings show that traveler reviews have a significant impact on online sales, with a 10 percent increase in traveler review ratings boosting online bookings by more than five percent. Our results highlight the importance of online user-generated reviews to business performance in tourism. © 2010 Elsevier Ltd. All rights reserved. Source


Wang J.,Harbin Institute of Technology
Genetics and molecular research : GMR | Year: 2012

Reconstructing the evolutionary history of a set of species is an elementary problem in biology, and methods for solving this problem are evaluated based on two characteristics: accuracy and efficiency. Neighbor-joining reconstructs phylogenetic trees by iteratively picking a pair of nodes to merge as a new node until only one node remains; due to its good accuracy and speed, it has been embraced by the phylogeny research community. With the advent of large amounts of data, improved fast and precise methods for reconstructing evolutionary trees have become necessary. We improved the neighbor-joining algorithm by iteratively picking two pairs of nodes and merging as two new nodes, until only one node remains. We found that another pair of true neighbors could be chosen to merge as a new node besides the pair of true neighbors chosen by the criterion of the neighbor-joining method, in each iteration of the clustering procedure for the purely additive tree. These new neighbors will be selected by another iteration of the neighbor-joining method, so that they provide an improved neighbor-joining algorithm, by iteratively picking two pairs of nodes to merge as two new nodes until only one node remains, constructing the same phylogenetic tree as the neighbor-joining algorithm for the same input data. By combining the improved neighbor-joining algorithm with styles upper bound computation optimization of RapidNJ and external storage of ERapidNJ methods, a new method of reconstructing phylogenetic trees, FastJoin, was proposed. Experiments with sets of data showed that this new neighbor-joining algorithm yields a significant speed-up compared to classic neighbor-joining, showing empirically that FastJoin is superior to almost all other neighbor-joining implementations. Source


Yang Y.,Harbin Institute of Technology | Yang E.-H.,University of Michigan | Li V.C.,University of Michigan
Cement and Concrete Research | Year: 2011

Autogenous healing of early ages (3 days) ECC damaged by tensile preloading was investigated after exposure to different conditioning regimes: water/air cycles, water/high temperature air cycles, 90%RH/air cycles, and submersion in water. Resonant frequency measurements and uniaxial tensile tests were used to assess the rate and extent of self-healing. The test results show that ECC, tailored for high tensile ductility up to several percent and with self-controlled crack width below 60 μm, experiences autogenous healing under environmental exposures in the presence of water. However, the recovery for these early age specimens is not as efficient as the recovery for more mature specimen, for the same amount of pre-damage and exposure to the same environment. Even so, the self-healing for these early age specimens demonstrates high robustness when the preloading strain is limited to 0.3%. This conclusion is supported by the evidence of resonant frequency and stiffness recovery of the healed ECC materials. © 2010 Elsevier Ltd. Source


Dong J.-G.,Harbin Institute of Technology
International Journal of Robust and Nonlinear Control | Year: 2013

SUMMARY Recently, a model for flocking was introduced by Cucker and Smale together with a proof of convergence. This proof established unconditional convergence to flocking (i.e., to a common velocity), provided the interaction between agents was strong enough and conditional convergence otherwise. The strength of the interaction is measured by a parameter β, and the critical value at which unconditional convergence stops holding is β = 1 â̂• 2. This model was extended by Shen to allow for a hierarchical leadership structure among the agents, and similar convergence results were proved. But, for discrete time, convergence result was only for the flock with an overall leader moving with a constant velocity. In this note, we establish convergence result for the flock with a free-will leader. © 2012 John Wiley & Sons, Ltd. Source


Bhushan B.,Ohio State University | Pan Y.,Ohio State University | Pan Y.,Harbin Institute of Technology
Langmuir | Year: 2011

The role of surface charge in fluid flow in micro/nanofluidics systems as well as the role of electric field to create switchable hydrophobic surfaces is of interest. In this work, the contact angle (CA) and contact angle hysteresis (CAH) of a droplet of deionized (DI) water were measured with applied direct current (DC) and alternating current (AC) electric fields. The droplet was deposited on a polystyrene (PS) surface, commonly used in various nanotechnology applications, coated on a doped silicon (Si) wafer. With the DC field, CA decreased with an increase in voltage. Because of the presence of a silicon oxide layer and a space charge layer, the change of the CA was found to be lower than with a metal substrate. The CAH had no obvious change with a DC field. An AC field with a positive value was applied to the droplet to study its effect on CA and CAH. At low frequency (lower than 10 Hz), the droplet was visibly oscillating. The CA was found to increase when the frequency of the applied AC field increased from 1 Hz to 10 kHz. On the other hand, the CA decreased with an increasing peak-peak voltage at or lower than 10 kHz. The CAH in the AC field was found to be lower than in the DC field and had a similar trend to static CA with increasing frequency. A model is presented to explain the data. © 2011 American Chemical Society. Source


Cui J.,Harbin Institute of Technology
Neural Computing and Applications | Year: 2013

Conventional representation methods try to express the test sample as a weighting sum of training samples and exploit the deviation between the test sample and the weighting sum of the training samples from each class (also referred to as deviation between the test sample and each class) to classify the test sample. In particular, the methods assign the test sample to the class that has the smallest deviation among all the classes. This paper analyzes the relationship between face images under different poses and, for the first time, devises a bidirectional representation method-based pattern classification (BRBPC) method for face recognition across pose. BRBPC includes the following three steps: the first step uses the procedure of conventional representation methods to express the test sample and calculates the deviation between the test sample and each class. The second step first expresses the training sample of a class as a weighting sum of the test sample and the training samples from all the other classes and then obtains the corresponding deviation (referred to as complementary deviation). The third step uses the score-level fusion to integrate the scores, that is, deviations generated from the first and second steps for final classification. The experimental results show that BRBPC classifies more accurately than conventional representation methods. © 2012 Springer-Verlag London Limited. Source


Wang H.,Nanchang Institute of Technology | Sun H.,Nanchang Institute of Technology | Li C.,Wuhan University | Rahnamayan S.,University of Ontario Institute of Technology | And 3 more authors.
Information Sciences | Year: 2013

Particle Swarm Optimization (PSO) has shown an effective performance for solving variant benchmark and real-world optimization problems. However, it suffers from premature convergence because of quick losing of diversity. In order to enhance its performance, this paper proposes a hybrid PSO algorithm, called DNSPSO, which employs a diversity enhancing mechanism and neighborhood search strategies to achieve a trade-off between exploration and exploitation abilities. A comprehensive experimental study is conducted on a set of benchmark functions, including rotated multimodal and shifted high-dimensional problems. Comparison results show that DNSPSO obtains a promising performance on the majority of the test problems. © 2012 Elsevier Inc. All rights reserved. Source


Yao X.,North China Electrical Power University | Wu L.,Harbin Institute of Technology | Zheng W.X.,University of Western Sydney
IEEE Transactions on Signal Processing | Year: 2011

This paper addresses the problem of fault detection filter design for discrete-time Markovian jump singular systems with intermittent measurements. The measurement transmission from the plant to the fault detection filter is assumed to be imperfect and a stochastic variable is utilized to model the phenomenon of data missing. Our attention is focused on the design of a fault detection filter such that the residual system is stochastically Markovian jump admissible and satisfies some expected performances. A new necessary and sufficient condition for a class of discrete-time Markovian jump singular systems to be stochastically Markovian jump admissible is proposed in the form of strict linear matrix inequalities. Sufficient conditions are established for the existence of the fault detection filter. Finally, a numerical example is provided to demonstrate the usefulness and applicability of the developed theoretical results. © 2011 IEEE. Source


Wang Y.-Z.,Harbin Institute of Technology | Li F.-M.,Beijing University of Technology
International Journal of Non-Linear Mechanics | Year: 2014

Based on the nonlocal continuum theory, the nonlinear primary resonance of nano beam with the axial initial load is investigated. The amplitude-frequency response for the primary resonance is derived with the multiple scale method and the stability is analyzed. The nonlinear primary resonance of nano beam is discussed with the influences of small scale effect, axial initial load, mode number, Winkler foundation modulus and the ratio of the length to the diameter. From the results, the typical hardening nonlinearity can be observed. Moreover, some significant and interesting nonlinear phenomena can be found for the primary resonance of nano beam. This work is expected to be useful for the design and analysis for the nonlinear dynamic behaviors of structures at nano scales. © 2014 Published by Elsevier Ltd. All rights reserved. Source


Zhou X.,Lanzhou University | Liu J.,Harbin Institute of Technology
Journal of Constructional Steel Research | Year: 2010

Reinforced concrete (RC) short columns are vulnerable to brittle shear failure during an earthquake. The objective of this research is to evaluate the performance enhancement of RC short columns tubed with circular or square tubes. Eight short columns were tested under combined constant axial load and cyclic lateral load. The tested specimens included three circular tubed RC (CTRC) columns and three square tubed RC (STRC) columns. Two common RC short columns including one circular RC column and one square RC column were also tested as control specimens. The test results indicated that common RC short columns suffered brittle shear failure with little ductility, while the ductility of tubed RC short columns was excellent due to the effective confinement of the outer thin tube to the core concrete. The lateral load strength of CTRC short columns increases with the increasing of axial load ratio, while the axial load ratio has little effect on the plastic deformation capacity of CTRC short columns. The shear strength increases with increasing of axial load ratio, while the plastic deformation capacity decreases with increasing of axial load ratio for STRC short columns. A circular tube prevents the core concrete from shear failure more effectively than a square tube for the tubed RC short columns. A modified ACI design method is adopted to calculate the nominal shear strength of STRC columns as well as CTRC columns based on the test and analysis results. © 2009 Elsevier Ltd. All rights reserved. Source


Dong Y.-L.,Harbin Institute of Technology
Magazine of Concrete Research | Year: 2010

This paper presents an energy-based model to determine the limit load-carrying capacity of concrete slab at elevated temperatures. This model considers the plastic energy dissipation both due to the resultant moment rotation and the extension of reinforcement along the yield line after the formation of the mechanism of the plastic hinge line in fire. The model could predict the load-carrying capacity of either rectangular or square concrete slabs with both orthotropic and isotropic reinforcement, and could interpret why failure of fracture of reinforcement is along the short span and occurred at both ambient and elevated temperatures. Comparison between the developed model and test results shows good correlation. © 2010 Thomas Telford Ltd. Source


Zhou X.,Lanzhou University | Liu J.,Harbin Institute of Technology
Journal of Constructional Steel Research | Year: 2010

The seismic behavior of tubed SRC short columns has been investigated by testing eight specimens subjected to combined constant axial compression and lateral cyclic load. Three circular tubed SRC columns (CTSRC) and three square tubed SRC (STSRC) columns were tested in this research with two common SRC columns for comparison. Different axial load ratios (n0 = 0.3, 0.4 and 0.5) have been adopted for the constant axial load. The test results indicate that the shear strength, plastic deformation capacity, ductility index, and energy dissipating capacity of the tubed SRC short columns were much higher than those of the SRC columns with the same steel ratio and axial compressive load. The lateral load strength of CTSRC and STSRC short columns increased with an increment in axial load level, while the axial load ratio has no obvious effect on the plastic deformation capacity of CTSRC and STSRC short columns. The steel tubes prevented the shear failure of the concrete more effectively in the circular columns than in the square ones. Shear connector studs should be used in CTSRC and STSRC short columns to prevent bond failure between concrete and flanges of the steel section. A modified ACI design method was adopted to calculate the nominal shear strength of STSRC columns as well as CTSRC columns. © 2010 Elsevier Ltd. All rights reserved. Source


Hu Q.,Harbin Institute of Technology
Journal of Dynamic Systems, Measurement and Control, Transactions of the ASME | Year: 2011

This paper presents a dual-stage control system design method for flexible spacecraft attitude tracking control and active vibration suppression by an embedded smart material as sensors/actuators. More specifically, a conventional sliding mode controller with the assumption of knowing system parameters is first designed that ensures asymptotical convergence of attitude tracking error described by error quaternion and its derivative in the presence of bounded parameter variation/disturbance. Then it is redesigned, such that the need for knowing the system parameters in advance is eliminated by using an adaptive updating law. For the synthesis of the controller, to achieve the prescribed L2 -gain performance criterion, the control gains are designed by solving a linear matrix inequality problem. Indeed, external torque disturbances/parametric error attenuations with respect to the performance measurement along with the control input penalty are ensured in the L 2 -gain sense. Even if this controller has the ability to reject the disturbance and deal with actuator constraint, it excites the elastic modes of flexible appendages, which will deteriorate the pointing performance. Then the undesirable vibration is actively suppressed by applying feedback control voltages to the piezoceramic actuator, in which the modal velocity feedback control method is employed for determining the control voltages. Numerical simulations are performed to show that attitude tracking and vibration suppression are accomplished, in spite of the presence of disturbances/parameter uncertainties and even control input constraint. Copyright © 2011 by ASME. Source


Ge J.,Harbin Institute of Technology
Energy Procedia | Year: 2011

Landfill gas emission associated with waste management is becoming significant environmental and energy issues in China. Currently, China is the world's largest municipal solid waste generator and approximate 80% of the generated waste is disposed in landfills. Landfill gas is a byproduct of anaerobic decomposition of organic waste and is typically comprised of methane and carbon dioxide. Due to the high heat value of methane, landfill gas has emerged as an easily available energy source. However, landfill gas collection is not common in most conventional landfills in China. Bioreactor technology provides an environmentally friendly way to increase landfill gas generation in a shorter period of time, which makes landfill gas collection more efficiently and economically. Model simulations were conducted to compare landfill gas generation in both conventional and bioreactor landfills and to estimate CO 2 emission reduction under various conditions in this study. The results indicate that bioreactor technology can provide a promising approach for waste management in China. © 2011 Published by Elsevier Ltd. Source


Feng Z.,University of Hong Kong | Lam J.,University of Hong Kong | Gao H.,Harbin Institute of Technology
International Journal of Robust and Nonlinear Control | Year: 2011

In this paper, the problems of delay-dependent robust stability analysis, robust stabilization and robust H control are investigated for uncertain discrete-time singular systems with state delay. First, by making use of the delay partitioning technique, a new delay-dependent criterion is given to ensure the nominal system to be regular, causal and stable. This new criterion is further extended to singular systems with both delay and parameter uncertainties. Then, without the assumption that the considered systems being regular and causal, robust controllers are designed for discrete-time singular time-delay systems such that the closed-loop systems have the characteristics of regularity, causality and asymptotic stability. Moreover, the problem of robust H control is solved following a similar line. The obtained results are dependent not only on the delay, but also on the partitioning size and the conservatism is non-increasing with reducing partitioning size. These results are shown, via extensive numerical examples, to be much less conservative than the existing results in the literature. © 2010 John Wiley & Sons, Ltd. Source


Takamura T.,Harbin Institute of Technology | Sato Y.,Kanagawa University
Journal of Power Sources | Year: 2011

In an attempt to provide a favorable active material of Li+ supercapacitor for HEV use, we modified the surface of an activated carbon fiber felt by coating with some transition metal oxides after mild-oxidation treatment. Major source of enhancing capacitance is attributed to be due to the nano-ionics mechanism proposed by Maier and coworkers. Cyclic voltammetry and constant current charge-discharge performance were examined for the surface modified samples in view of power capability. The oxides of Ag, Cu, Pd, and Sn were found effective to enhance the capacitance and high rate charge/discharge performance. The cycleability test was performed as well. © 2011 Elsevier B.V. All rights reserved. Source


Kar S.,Harbin Institute of Technology | Ho Y.K.,Academia Sinica, Taiwan
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2010

Effect of Debye plasmas on the dispersion coefficients C8, C10, and C12 for interactions between atoms has been investigated using highly accurate correlated exponential basis functions. In the free-atom case, the dispersion C12 coefficient and the hexadecapole polarizability for helium are reported. The dispersion coefficients, hexadecapole polarizability, and 1s5g 1Ge state energy of helium for different screening parameters are also reported. © 2010 The American Physical Society. Source


Ye J.,Harbin Institute of Technology | Mu Y.,Beijing Forestry University | Cheng X.,Beijing Forestry University | Sun D.,Beijing Forestry University
Bioresource Technology | Year: 2011

Treatment of a fresh leachate with high-strength organics and calcium from municipal solid waste (MSW) incineration plant by an up-flow anaerobic sludge blanket (UASB) reactor was investigated under mesophilic conditions, emphasizing the influence of organic loading rate (OLR). When the reactor was fed with the raw leachate (COD as high as 70,390-75,480mg/L) at an OLR of 12.5kg COD/(m3d), up to ∼82.4% of COD was removed suggesting the feasibility of UASB process for treating fresh leachates from incineration plants. The ratio of volatile solids/total solids (VS/TS) of the anaerobic sludge in the UASB decreased significantly after a long-term operation due to the precipitation of calcium carbonate in the granules. Scanning electron microscopy (SEM) observation shows that Methanosaeta-like species were in abundance, accompanied by a variety of other species. The result was further confirmed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and sequencing. © 2011. Source


Zhu Q.,Harbin Institute of Technology
Neurocomputing | Year: 2010

In this paper, we propose an efficient nonlinear feature extraction method using kernel-based minimum squared error (KMSE). This improved method is referred to as reformative KMSE (RKMSE). In RKMSE, we use a linear combination of a small portion of samples that are selected from the training sample set, i.e. "significant nodes", to approximate to the transform vector of KMSE in kernel space. As a result, RKMSE is much superior to naive KMSE in computational efficiency of feature extraction. Experimental results on several benchmark datasets illustrate that RKMSE can efficiently classify the data with high recognition correct rate. © 2010 Elsevier B.V. Source


Alam M.M.,Harbin Institute of Technology
Journal of Fluids and Structures | Year: 2016

Flow-induced forces on two tandem circular cylinders of identical diameter are numerically studied at a Reynolds number of 200. The cylinder center-to-center spacing ratio is varied from 2 to 9. We focus on fluctuating (rms) lift coefficient of the upstream cylinder, vortex dynamics in the gap between cylinders, and phase lag between vortex shedding from the two cylinders. The phase lag was a linear function of the spacing ratio as known in the literature; but it is, as proved here, indeed a nonlinear function of the spacing ratio, Strouhal number and convection velocity of vortices in the gap between the cylinders. The shedding from the two cylinders turns out to be inphase and antiphase alternately as the spacing ratio increases. We unearth that both phase lag and spacing ratio influence the fluctuating lift of the upstream cylinder. With an increase in the spacing ratio, while the influence of the spacing ratio on fluctuating lift diminishes rapidly in an overdamped manner, that of the phase lag makes the fluctuating lift variation underdamped sinusoidal. The inphase and antiphase flows correspond to a local maximum and a local minimum, respectively, in the fluctuating lift variation. An equation is deduced, showing the relationship between the fluctuating lift, spacing ratio, and phase lag. The physics behind the damped-sinusoidal variation in the fluctuating lift is discussed. The investigation directs that the streamwise separation between two tandem wings of airplanes/submarines should be taken into account or optimized. It would also be interesting to see whether fish exploits phase-lag-induced lift to enhance its forward thrust. © 2016 Elsevier Ltd. Source


Dong J.-G.,Harbin Institute of Technology
Automatica | Year: 2016

This paper introduces a discontinuous rendezvous algorithm for multi-agent systems which allows a group of agents to achieve finite-time rendezvous with connectivity preservation as well as disturbance rejection. The proposed discontinuous rendezvous algorithm is based on a class of general communication functions with certain available information range. Nonsmooth stability analysis and graph theory are employed to obtain the finite-time rendezvous. An upper bound on the convergence time is also given. Our result simultaneously satisfies the three features: connectivity preservation, disturbance rejection and finite-time convergence. © 2016 Elsevier Ltd. All rights reserved. Source


Zhou B.,Harbin Institute of Technology
Automatica | Year: 2016

This paper is concerned with asymptotic stability analysis of linear time-varying (LTV) systems. With the help of the notion of stable functions, some differential Lyapunov inequalities (DLIs) based necessary and sufficient conditions are derived for testing asymptotic stability, exponential stability and uniformly exponential stability of general LTV systems. With the help of the concept of (non-uniformly) exponential stability, a class of upper-triangular LTV systems is carefully investigated based on the developed stability analysis approaches. A couple of numerical examples with some of them borrowed from the literature is provided to illustrate the effectiveness of the proposed theoretical results. © 2016 Elsevier Ltd. All rights reserved. Source


Lai Z.,Harbin Institute of Technology
IET Computer Vision | Year: 2012

One of the major disadvantages of the linear dimensionality reduction algorithms, such as principle component analysis (PCA) and linear discriminant analysis (LDA), is that the projections are lack of physical interpretation. Moreover, which features or variables play an important role in feature extraction and classification in classical linear dimensionality reduction methods is still not investigated well. This paper proposes a novel supervised learning method called sparse local discriminant projections (SLDPs) for linear dimensionality reduction. Differed from the recent manifold-learning-based methods such as local preserving projections (LPPs), SLDP introduces a sparse constraint into the objective function and integrates the local geometry, discriminant information and within-class geometry to obtain the sparse projections. The sparse projections can be efficiently computed by the Elastic Net. The most important and interesting thing is that the sparse projections learned by SLDP have a direct physical interpretation and provide us the discriminant knowledge and insightful understanding for the extracted features. The experimental results show that SLDP can give reasonable semantic results and achieves competitive performance compared with some techniques such as PCA, LPP, neighbourhood preserving embedding (NPE) and the recently proposed unified sparse subspace learning (USSL). ©The Institution of Engineering and Technology 2012. Source


Zhao J.,South China University of Technology | Wu B.,Harbin Institute of Technology | Ou J.,Dalian University of Technology
Journal of Structural Engineering (United States) | Year: 2012

In a previous study by the authors, the cyclic behavior of a novel type of pin-connected angle steel buckling-restrained brace (ABRB) was examined, and the failure mechanism in the core projection of the ABRB induced by an excessive bending effect caused by end rotation was discussed. In this paper, the occurrence mechanism of end rotation modes and the bending effect in the core projection of an ABRB are first investigated based on the previous test results, which shows that end rotation demands would be significantly increased with the presence of a gap and an additional bending effect could be observed if the end rotation demands were large enough to cause two-point contact at the core ends. Then, a new method to predict the flexural demand on pin-connected BRBs is proposed by considering the effect of the end rotation modes, clearance, initial eccentricity, and initial deflection of casing. The design criteria to prevent yielding of the core projection are presented and further verified by the previous test results. Furthermore, the effects of key influential parameters on the flexural demand on core projection are discussed based on the analytical results. It is found that such a bending effect can be significantly reduced by decreasing the gap or increasing the constrained length of the core stiffening segment. The C-mode end rotation with single curvature bending configuration is found to be generally the most unfavorable case for core projection design. Finally, several design recommendations are provided for pin-connected BRBs. © 2012 American Society of Civil Engineers. Source


Zuo W.,Harbin Institute of Technology | Lin Z.,Microsoft
IEEE Transactions on Image Processing | Year: 2011

This paper proposes a generalized accelerated proximal gradient (GAPG) approach for solving total variation (TV)-based image restoration problems. The GAPG algorithm generalizes the original APG algorithm by replacing the Lipschitz constant with an appropriate positive-definite matrix, resulting in faster convergence. For TV-based image restoration problems, we further introduce two auxiliary variables that approximate the partial derivatives. Constraints on the variables can easily be imposed without modifying the algorithm much, and the TV regularization can be either isotropic or anisotropic. As compared with the recently developed APG-based methods for TV-based image restoration, i.e., monotone version of the two-step iterative shrinkage/thresholding algorithm (MTwIST) and monotone version of the fast IST algorithm (MFISTA), our GAPG is much simpler as it does not require to solve an image denoising subproblem. Moreover, the convergence rate of O(k-2) is maintained by our GAPG, where k is the number of iterations; the cost of each iteration in GAPG is also lower. As a result, in our experiments, our GAPG approach can be much faster than MTwIST and MFISTA. The experiments also verify that our GAPG converges faster than the original APG and MTwIST when they solve identical problems. © 2011 IEEE. Source


Wang B.,Harbin Institute of Technology
Journal of Intelligent Material Systems and Structures | Year: 2012

Magnetoelectroelastic materials are inherently brittle and prone to cracking. It is important to understand how cracks influence the magnetoelectrical coupling properties of the magnetoelectroelastic materials. This article establishes an analytical model for a finite crack in a finite magnetoelectroelastic medium. The stress, electric displacement, and magnetic induction and their intensity factors are obtained by the integral equation technique. The temperature effect is also studied. The effect of cracking on the effective thermomagnetoelectromechanical properties is discussed. In addition, crack is modeled as a notch of finite height to study the effect of the crack-face electric and magnetic boundary condition assumptions on the predicted properties of the magnetoelectroelastic medium. © The Author(s) 2012. Source


Zhou B.,Harbin Institute of Technology
International Journal of Control | Year: 2014

In this paper, we study observer-based output feedback control of discrete-time linear systems with both multiple input and output delays. By generalising our recently developed truncated predictor feedback approach for state feedback stabilisation of discrete-time time-delay systems to the design of observer-based output feedback, two types of observer-based output feedback controllers, one being memory and the other memoryless, are constructed. Both full-order and reduced-order observer-based controllers are established in both the memory and memoryless schemes. It is shown that the separation principle holds for the memory observer-based output feedback controllers, but does not hold for the memoryless ones. We further show that the proposed observer-based output feedback controllers solve both the l2 and l∞ semi-global stabilisation problems. A numerical example is given to illustrate the effectiveness of the proposed approaches. © 2014 © 2014 Taylor & Francis. Source


Lu H.,Harbin Institute of Technology | Gou J.,University of Central Florida
Polymers for Advanced Technologies | Year: 2012

A novel shape-memory nanocomposite that exhibits electrical actuation capabilities was fabricated by incorporating a conductive multiwalled carbon nanotube (MWCNT) nanopaper into shape-memory polymer matrix. The self-assembled MWCNT nanopaper was made on hydrophilic polycarbonate membrane. This process was based on well-defined dispersion of the nanosized individual MWCNT and controlled traditional pressure vacuum deposition procedure. The self-assembled MWCNTs in the nanopaper provided a percolating conductive network with a large interfacial area. It not only offered a high electrical conductivity but also simultaneously enhanced recovery speed by electrically resistive heating, with increasing the content of MWCNT nanopaper in nanocomposite. © 2011 John Wiley & Sons, Ltd. Source


This paper presents Gabor filter based optical image recognition using Fractional Power Polynomial model based Common Kernel Discriminant Locality Preserving Projection. This method tends to solve the nonlinear classification problem endured by optical image recognition owing to the complex illumination condition in practical applications, such as face recognition. The first step is to apply Gabor filter to extract desirable textural features characterized by spatial frequency, spatial locality and orientation selectivity to cope with the variations in illumination. In the second step we propose Class-wise Locality Preserving Projection through creating the nearest neighbor graph guided by the class labels for the textural features reduction. Finally we present Common Kernel Discriminant Vector with Fractional Power Polynomial model to reduce the dimensions of the textural features for recognition. For the performance evaluation on optical image recognition, we test the proposed method on a challenging optical image recognition problem, face recognition. © 2012 Elsevier Ltd. All rights reserved. Source


Kan W.,China Academy of Engineering Physics | Li X.,Harbin Institute of Technology
European Polymer Journal | Year: 2013

In the present research, a type of imprinted hydrogels, in which 5-fluorouracil is complexed non-covalently to the monomers and cross-linked into the hydrogel matrix, is synthesized in order to evaluate the possibility of their applications in sustaining the release of 5-fluorouracil due to the drug's heightened interactions with the imprinted binding sites. Because of the hydrophility, hydrogels can absorb large amounts of water. As a result, drug release mechanisms are different from hydrophobic polymers. Mathematical model has been established to predict the drug release from the hydrogel matrix as a function of time. The drug release mechanism when immersed in release medium is discussed based on mathematical analysis. Swelling studies are performed and the capability of the hydrogels to reload 5-fluorouracil in aqueous solutions is evaluated. In vitro release studies after reloading are conducted. Mathematical analysis suggest that drug release kinetics from the hydrogels fit Fickian mechanism, further evaluation of the fitness for different hydrogel types reveal that the conformation of binding sites can play a very important role in deciding the kind of drug release mechanism. Experiments reveal that all hydrogels show swelling property. The imprinted hydrogels bind much more 5-fluorouracil than non-imprinted ones, and they sustain 5-fluorouracil release better than non-imprinted hydrogels. This research indicates that the imprinted hydrogels would be a potential promising device for drug delivery. © 2013 Elsevier Ltd. All rights reserved. Source


Tang Z.,Harbin Institute of Technology | Zhang B.,Beihang University
Composites Part B: Engineering | Year: 2012

Macro/micromulti-scale analysis based on the efficient implementation of the Generalized Method of Cells coupled with classical lamination theory was conducted to predict failure of composite laminates, applying failure criteria at the constituent level, including fiber, matrix and interface. Representative unit cells with different fiber arrays were constructed in order to study the effect of reinforcement architecture and failure criteria on strength prediction of composite laminates. In order to compare the micromechanics model's accuracy with commonly-used macroscopic failure theories, the experimental data obtained from the Worldwide Failure Exercise (WWFE) was utilized, and a quantitative assessment method for failure envelopes was developed to evaluate the model's performance. Finally, the types of representative unit cell architectures and failure theories which are applicable for different layups were identified. The results indicate that the predictive performance of the employed micromechanics-based model is closest to the three leading macroscopic failure criteria of Puck, Cuntze and Tsai-Wu, and better than all other microscopic-based failure criteria (Chamis, Mayes, Huang), employed in the WWFE study. © 2011 Elsevier Ltd. All rights reserved. Source


Li J.,Harbin Institute of Technology | Li J.,University of Western Brittany
Journal of Magnetism and Magnetic Materials | Year: 2012

Choosing TbFe as the magnetostrictive layer and using soft ferromagnetic materials (FM=Fe, Py-permalloy, FeCo) as the inductive layer, we report the magnetization and magnetostriction of the S/FM(10 nm)/TbFe(10 nm) coupled bilayer (S-glass substrate). The magnetization of the coupled bilayer is attributed to the soft ferromagnetic layer and there is no contribution from the TbFe layer. Interfacial exchange interaction plays an important role in determining the magnetostriction of the coupled bilayer. The effect coming from the deposition Argon pressure on the magnetostriction of the coupled bilayer was also investigated. © 2011 Elsevier B.V. All rights reserved. Source


Zhang B.,Harbin Institute of Technology
IET Control Theory and Applications | Year: 2013

An approach for eigenvalue assignment in linear descriptor systems via output feedback is proposed. Sufficient conditions in order that a given set of eigenvalues is assignable are established. Parametric form of the desired output feedback gain matrix is also given. The approach assigns the full number of generalised eigenvalues, guarantees the closed-loop regularity and overcomes the defects of some previous works. © The Institution of Engineering and Technology 2013. Source


Dong J.-G.,Harbin Institute of Technology
International Journal of Robust and Nonlinear Control | Year: 2015

Summary: This paper considers the stability problem for a class of switched positive nonlinear systems (SPNSs), which includes switched positive linear systems as a special case. We derive a necessary and sufficient condition for stability of continuous-time SPNSs defined by homogeneous and cooperative vector fields under average dwell time switching. A corresponding necessary and sufficient condition is also given for stability of discrete-time SPNSs defined by homogeneous and order-preserving vector fields under average dwell time switching. The stability results for switched positive linear systems, which have been studied in the literature, can be easily obtained. We also extend the results to general switched linear systems. Finally, a numerical example is provided to illustrate the effectiveness of our results. © 2015 John Wiley & Sons, Ltd. Source


Ding X.F.,University of Science and Technology Beijing | Lin J.P.,University of Science and Technology Beijing | Zhang L.Q.,University of Science and Technology Beijing | Su Y.Q.,Harbin Institute of Technology | Chen G.L.,University of Science and Technology Beijing
Acta Materialia | Year: 2012

The lamellar microstructure of TiAl-Nb alloys with and without low boron additions is controlled using double directional solidification (DS). In alloys without the addition of boron, the β phase is seeded during double DS. Complete peritectic transformation occurs in both the dendritic and interdendritic regions, which can lead to the successful alignment of both the high-temperature α phase and the lamellar microstructures. Well-aligned lamellar microstructures can be easily achieved if the alloy composition is close to the peritectic point on the hypo-peritectic side. In alloys with low boron additions, however, the competitive growth of the α phase breaks the continuity of the lamellar microstructure in the region ahead of stable growth, which finally results in columnar grain coarsening and unsuccessful alignment of the lamellar microstructures. © 2011 Published by Elsevier Ltd. on behalf of Acta Materialia Inc. All rights reserved. Source


Gao Q.,Hefei University of Technology | Gao Q.,City University of Hong Kong | Feng G.,City University of Hong Kong | Feng G.,Nanjing University of Science and Technology | And 2 more authors.
IEEE Transactions on Fuzzy Systems | Year: 2013

This paper investigates the universal fuzzy model and universal fuzzy controller problems for stochastic nonaffine nonlinear systems. The underlying mechanism of stochastic fuzzy logic is first discussed, and a stochastic generalized fuzzy model with new stochastic fuzzy rule base is then given. Based on their function approximation capability, these kinds of stochastic generalized fuzzy models are shown to be universal fuzzy models for stochastic nonaffine nonlinear systems under some sufficient conditions. An approach to stabilization controller design for stochastic nonaffine nonlinear systems is then developed through their stochastic generalized Takagi-Sugeno (T-S) fuzzy approximation models. Then, the results of universal fuzzy controllers for two classes of stochastic nonlinear systems, along with constructive procedures to obtain the universal fuzzy controllers, are also provided, respectively. Finally, a numerical example is presented to illustrate the effectiveness of the proposed approach. © 1993-2012 IEEE. Source


Aung N.Z.,Mandalay University | Li S.,Harbin Institute of Technology
Energy Conversion and Management | Year: 2013

In this work, the effect of riser diameter and its inclination angle on system parameters in a two-phase closed loop thermosyphon solar water heater has been numerically investigated. Here, receivable heat flux by the collector, circulating mass flow rate, driving pressure, total pressure drop, heat transfer coefficient in risers and collector efficiency are defined as system parameters. For this aim, a model of two-phase thermosyphon solar water heater that is acceptable for various inclinations is presented and variations of riser diameter and inclination are considered. The riser tube size is varied from 1.25 cm to 2.5 cm with inclination range 2-75. The system absolute pressure is set as 3567 Pa and water is chosen as working fluid. The results show that higher inclination angle is required for higher latitude location to obtain maximum solar heat flux. At local solar noon of 21.996 north latitude, the optimum inclination angle increases in the range of 24-44 with increasing of riser diameter giving maximum circulating mass flow rate from 0.02288 kg/s to 0.03876 kg/s. The longer two-phase heat transfer characteristics can be obtained at smaller inclination angles and mass flow rate for all riser tube sizes. Therefore, it is observed that the optimum inclination angles and diameters for solar heat flux, circulating mass flow rate and heat transfer coefficient in two-phase thermosyphon systemdo not coincide. From this work, better understanding and useful information are provided for constructing two-phase thermosyphon solar heaters. © 2013 Elsevier Ltd. All rights reserved. Source


Huang X.-L.,Tongji University | Wang G.,Harbin Institute of Technology | Hu F.,University of Alabama
IEEE Transactions on Vehicular Technology | Year: 2013

Recently, compressive sensing (CS) and spectrum sensing have been two hot topics in the signal processing and cognitive radio network (CRN) fields, respectively. Due to the sampling rate limitation of the analog-to-digital converter in spectrum-sensing circuits, some works have proposed integrating these two techniques to achieve low-overhead spectrum sensing in CRNs. These works aim to minimize spectrum reconstruction errors based on linear regression methods, and ℓ1-norm is typically used to make a tradeoff between spectrum sparseness and reconstruction accuracy. However, since the interference range of primary users is limited, multiple clusters in the CRN may not share a common sparse spectrum, and thus, the ℓ1-norm may not be appropriate to handle all clusters in CS inversion. Hence, we propose a novel multitask spectrum-sensing method based on spatiotemporal data mining methods. In each cluster, we assume that the spectrum sensing is executed in a synchronized way. The cluster head (CH) manages the operations, and a common sparseness hyperparameter is used to make a consensus decision. Among multiple clusters, synchronized CS sampling is not required in our scheme; instead, the Dirichlet process prior is employed to make an automatic grouping of the spectrum-sensing results among different clusters with a common sparseness hyperparameter shared inside each group. To exploit the time-domain relevance among consecutive CS observations, a hidden Markov model is employed to describe the relationship between the hidden subcarrier states and the consecutive CS observations, and the Viterbi algorithm is used to make an accurate spectrum decision for each secondary user. Simulation results show that our proposed algorithm can successfully exploit the spatiotemporal relationship to achieve higher spectrum-sensing performance in terms of normalized mean square error, probability of correct detection, and probability of false alarm, compared with a few other related works. © 1967-2012 IEEE. Source


Dong J.-G.,Harbin Institute of Technology
IEEE Transactions on Automatic Control | Year: 2015

This technical note studies the stability problem of homogeneous positive systems of any degree with time-varying delays. Delay-independent conditions are derived for asymptotic and finite-time stability. Estimates on the decay rates, which reveal how the system delays affect the rates of convergence, are obtained. More precisely, this technical note features three contributions. First, we derive a necessary and sufficient condition for global polynomial stability of continuous-time homogeneous cooperative systems with time-varying delays when the degree of homogeneity is greater than one. Second, we characterize finite-time stability of continuous-time homogeneous cooperative delay-free systems of degree smaller than one. Finally, for discrete-time positive systems with time-varying delays, a local exponential stability criterion is established when the vector fields are order-preserving and homogeneous of degree greater than one. An illustrative example is given to show the effectiveness of our results. © 1963-2012 IEEE. Source


Song Q.,Harbin Institute of Technology | Ge L.,Princeton University | Redding B.,Yale University | Cao H.,Yale University
Physical Review Letters | Year: 2012

We demonstrate a robust and generic mechanism, which we term "chaos-assisted channeling," to achieve unidirectional output from wave-chaotic microcavities with long-lived resonances. It utilizes the coexistence of regular and chaotic ray dynamics in most deformed microcavities. Long-lived resonances are formed by total internal reflection on classical periodic orbits, and their leakage into the chaotic region of the phase space is efficiently channeled into an attached waveguide without additional loss. We explain this behavior using a ray dynamics analysis which is confirmed via numerical simulations and experimental demonstration. © 2012 American Physical Society. Source


Leonov G.A.,Harbin Institute of Technology
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2012

The general method for proving the existence of homoclinic trajectories in dissipative systems is developed. The applications of this method to Lorenz-like systems: Lorenz, Shimizu-Morioka, Lu and Chen systems are demonstrated. A criterion for the existence of a homoclinic trajectory within a given family of differential equations (Fishing principle) is presented. New numerical algorithm for the approximation of a homoclinic point in parameters space is constructed. The comparison with Kaplan-Yorke and Shilnikov results is made. © 2012 Elsevier B.V. Source


Leonov G.A.,Harbin Institute of Technology | Kuznetsov N.V.,University of Jyvaskyla | Kuznetsov N.V.,Saint Petersburg State University | Vagaitsev V.I.,University of Jyvaskyla | Vagaitsev V.I.,Saint Petersburg State University
Physica D: Nonlinear Phenomena | Year: 2012

The hidden oscillations (a basin of attraction of which does not contain neighborhoods of equilibria) have been obtained first in the 50-60s of the 20th century in automatic control systems with scalar piecewise-linear nonlinearity. This brings up the question about the excitation nature of hidden oscillations. In the present paper it is shown that hidden oscillations can exist not only in systems with piecewise-linear nonlinearity but also in smooth systems. Here the possibility of the existence of a hidden chaotic attractor in a modified Chua's system with a smooth characteristic of nonlinear element is demonstrated. © 2012 Elsevier B.V. All rights reserved. Source


Wang X.,Harbin Institute of Technology
International Journal of Systems Science | Year: 2013

In this article, the distributed formation output regulation problem of linear heterogeneous multi-agent systems with uncertainty under switching topology is considered. It is a generalised framework for multi-agent coordination problems, which contains or concerns a variety of important multi-agent problems in a quite unified way. Its background includes active leader following formation for the agents to maintain desired relative distances and orientations to the leader with a predefined trajectory, and multi-agent formation with environmental inputs. With the help of canonical internal model we design a distributed dynamic output feedback to handle the distributed formation output regulation problem. © 2013 Copyright Taylor and Francis Group, LLC. Source


Pan L.,Tsinghua University | Zhu X.-D.,Harbin Institute of Technology | Xie X.-M.,Tsinghua University | Liu Y.-T.,Tsinghua University
Advanced Functional Materials | Year: 2015

Today, the ever-increasing demand for large-size power tools has provoked worldwide competition in developing lithium-ion batteries having higher energy and power densities. In this context, advanced anode materials are being extensively pursued, among which TiO2 is particularly promising owing to its high safety, excellent cost and environmental performances, and high cycle stability. However, TiO2 is faced with two detrimental deficiencies, that is, extremely low theoretical capacity and conductivity. Herein, a smart hybridization strategy is proposed for the hierarchical co-assembly of TiO2 nanorods and Fe3O4 nanoparticles on pristine graphene nanosheets, aiming to simultaneously address the capacity and conductivity deficiencies of TiO2 by coupling it with high-capacity (Fe3O4) and high-conductivity (pristine graphene) components. The resulting novel, multifunctional ternary heterostructures effectively integrate the intriguing functionalities of the three building blocks: TiO2 as the major active material can adequately retain such merits as high safety and cycle stability, Fe3O4 as the auxiliary active material can contribute extraordinarily high capacities, and pristine graphene as the conductive dopant can guarantee sufficient percolation pathways. Benefiting from a remarkable synergy, the ternary heterostructures deliver superior reversible capacities and rate capabilities, thus casting new light on developing next-generation, high-performance anode materials. A smart hybridization strategy is proposed for the hierarchical co-assembly of TiO2 nanorods and Fe3O4 nanoparticles on pristine graphene nanosheets, aiming to simultaneously address the deficiencies of TiO2 by coupling it with high-capacity (Fe3O4) and high-conductivity (pristine graphene) components. Benefiting from a remarkable synergy, the resulting novel, multifunctional ternary heterostructures deliver superior reversible capacities and rate capabilities, thus casting new light on developing advanced LIB anode materials. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Wu B.,Harbin Institute of Technology
Journal of Guidance, Control, and Dynamics | Year: 2016

A feedback control scheme is proposed for a spacecraft attitude stabilization system with quantized control torque. A logarithmic type quantizer is studied, which has sufficient precision and requires a low communication rate. The quantization parameter is chosen based on the given controller design parameters and inertial matrix of spacecraft, which ensure the system stability and stabilization error within an adjustable bound. Simulation results demonstrate the effectiveness of the proposed control scheme. Source


Li Sun et al. showed that the temperature corresponding to the maximum recovery stress in constrained recovery was roughly the temperature at which pre-deformation, also known as the temperature memory effect (TME), occurred in shape memory polymers (SMPs). A theoretical framework was presented to investigate the underlying mechanisms for the TME. Here, we show that the scope of this report remains limited to the theoretical framework. In this comment, a phenomenological model is proposed to quantitatively separate the effect of stored mechanical energy on the TME in SMPs, in combination with the relaxation theory and the experimental work of Pierre Miaudet et al. © 2013 The Royal Society of Chemistry. Source


Guo C.,Harbin Institute of Technology
Wei sheng wu xue bao = Acta microbiologica Sinica | Year: 2010

We reviewed existing literature concerning the effects of probiotics on serum cholesterol levels in animals and humans, with particular attention to the possible mechanisms of their action. Probiotics are live microorganisms, which, when administered in adequate amounts, confer a health benefit on the host. One specific benefit that has been reported is that certain probiotic strains (e. g. lactobacilli, bifidobacteria and enterococci) can lower serum cholesterol levels. However, conclusions regarding such hypocholesterollemic effects can vary from studies on animals and humans due to differences in their physiology. As for the cholesterol-lowering mechanisms, different hypotheses have been proposed, including: (I) cholesterol is absorbed into the cellular membrane or cytoplasm; (II) cholesterol is bound to the cellular surface; (III) cholesterol is co-precipitated with free bile acids; (IV) conjugated bile acids were hydrolyzed by probiotics and the resulting free bile acids are more likely than are conjugated ones to be excreted from the body; (V) free bile acids were bound to the cellular surface by capsule exocellular polysaccharides produced by probiotics; (VI) food-derived indigestible carbohydrates were fermented by probiotics to produce propanoic acid in the gut, which can then decrease systemic levels of serum cholesterol by inhibiting hepatic cholesterol synthesis; (VII) a reduction in cholesterol absorption by probiotics through the down-regulation of NPC1L1 gene expression of cells; and (VIII) cholesterol micelle is disrupted by probiotics. The future research is needed to further confirm these hypotheses. Source


Cui J.,Harbin Institute of Technology
Optik | Year: 2013

In order to improve the accuracy of palmprint recognition, multispectral imaging has been employed with a fusion strategy to acquire more discriminative information. The PolyU multispectral palmprint images contain four kinds of palmprint images which are respectively captured under red, green, blue and near infrared illuminations and contain much information than the single band. However, there is also redundant information. How to extract the critical information among the multispectral palmprint images and to fuse them is an emerging problem. In this paper we address the problem of selecting bands from the original four bands, and use the extended general color image discriminant (GCID) model to generate three new color components for further improvement of the recognition performance. Experiments using the PolyU multispectral palmprints database show the effectiveness of the proposed models and fusion strategy. © 2012 Elsevier GmbH. All rights reserved. Source


Lin C.-W.,Harbin Institute of Technology | Hong T.-P.,National University of Kaohsiung | Hong T.-P.,National Sun Yat - sen University
Wiley Interdisciplinary Reviews: Data Mining and Knowledge Discovery | Year: 2013

The Internet has become an unlimited resource of knowledge, and is thus widely used in many applications. Web mining plays an important role in discovering such knowledge. This mining can be roughly divided into three categories, including Web usage mining, Web content mining, and Web structure mining. Data and knowledge on the Web may, however, consist of imprecise, incomplete, and uncertain data. Because fuzzy-set theory is often used to handle such data, several fuzzy Web-mining techniques have been proposed to reveal fuzzy and linguistic knowledge. This paper reviews these techniques according to the three Web-mining categories above-fuzzy Web usage mining, fuzzy Web content mining, and fuzzy Web structure mining. Some representative approaches in each category are introduced and compared. © 2013 John Wiley & Sons, Inc. Source


Zhang X.,Hong Kong Polytechnic University | Shen L.,Chongqing University | Zhang L.,Harbin Institute of Technology
Renewable and Sustainable Energy Reviews | Year: 2013

The generation of significant amount of emissions from building construction process has led the promotion of controlling emissions as an important strategy for implementing sustainable development principles in the built environment. The emissions incurred during various stages include carbon dioxide, methane, nitrous oxide, sulphur dioxide, carbon monoxide, nitrogen oxide, non methane volatile organic compounds and particulate matter. This paper conducts the life cycle assessment of the air emissions by using a particular case to examine emissions during construction stage. This study examines the emissions sources in each of the six stages and presents an inventory analysis method to measure air emissions to quantify the air emissions during the six life cycle stages for buildings. This method can help evaluating the impacts of implementing a building on the air quality, thus actions can be taken in early stages to reduce the environmental impacts during building life cycle. A case study is presented to demonstrate the practical application of the method with reference to the building practices for all life cycle stages in Hong Kong. © 2012 Elsevier Ltd. Source


Ma K.,Harbin Institute of Technology
IEEE Transactions on Industrial Electronics | Year: 2013

In the paper 'Quasi-continuous higher order sliding-mode controllers for space-attitude-tracking maneuvers' (IEEE Trans. Ind. Electron., vol. 57, no. 4, pp. 1436-1444, Apr. 2010), higher order sliding-mode control laws are applied to the attitude-tracking maneuvers of spacecraft. It is pointed out in the author's comments that the proposed applications of higher order sliding-mode control, although in the form of second- and third-order sliding-mode controls, can only realize first-order sliding-mode dynamics because of the improperly chosen sliding vectors. The proposed sliding vectors in the paper are suitable when integrators or a first-order lag is added into the system. In the author's comments, alternative measures to realize second- and third-order sliding-mode dynamics are suggested. © 1982-2012 IEEE. Source


Zhou J.,Harbin Institute of Technology
Applied Catalysis A: General | Year: 2016

Density functional theory (DFT) calculations were used to study the mechanisms of dehydrogenation of formic acid catalyzed by two Ru complexes, including P(CH2CH2PPh2)3RuH+ (P(CH2CH2PPh2)3 = tris[2-(diphenylphosphino)ethyl]phosphine) and P(CH2CH2CH2PiPr2)3RuH+ (P(CH2CH2CH2PiPr2)3 = tris[3-(diisopropylphosphino)propyl]phosphine). Two competing catalytic cycles (I and II) have been explored. In cycle I, the catalytic reaction starts with a direct hydride transfer from HCOO- to a Ru center, releasing CO2 in the first place, followed by H2 production, while in cycle II, neutral formic acid approaches Ru catalyst to produce H2 molecule prior to CO2 generation via β-hydride elimination. The computational results show that cycle I is more accessible than cycle II, regardless of the ligands surrounding Ru center. The calculated overall Gibbs free energy barriers for formic acid dehydrogenation catalyzed by P(CH2CH2PPh2)3RuH+ (14.3 kcal/mol) is significantly lower than its iron analogue in the previous experimental and theoretical studies (18.9 kcal/mol) at the same level of theory. More interestingly, isopropyl group, a more electron-donating group than phenyl group, leads to an even lower reaction barrier of P(CH2CH2CH2PiPr2)3RuH+ (12.9 kcal/mol) than P(CH2CH2PPh2)3RuH+, indicating a more positive role the ligand could potentially play in the performance of the catalysts. Our results pave a new way to design more efficient catalysts for formic acid dehydrogenation. © 2016 Elsevier B.V. All rights reserved. Source


Cheng Y.,Duke University | Lu S.,Duke University | Lu S.,Harbin Institute of Technology | Zhang H.,Duke University | And 3 more authors.
Nano Letters | Year: 2012

Flexible and lightweight energy storage systems have received tremendous interest recently due to their potential applications in wearable electronics, roll-up displays, and other devices. To manufacture such systems, flexible electrodes with desired mechanical and electrochemical properties are critical. Herein we present a novel method to fabricate conductive, highly flexible, and robust film supercapacitor electrodes based on graphene/MnO 2/CNTs nanocomposites. The synergistic effects from graphene, CNTs, and MnO 2 deliver outstanding mechanical properties (tensile strength of 48 MPa) and superior electrochemical activity that were not achieved by any of these components alone. These flexible electrodes allow highly active material loading (71 wt % MnO 2), areal density (8.80 mg/cm 2), and high specific capacitance (372 F/g) with excellent rate capability for supercapacitors without the need of current collectors and binders. The film can also be wound around 0.5 mm diameter rods for fabricating full cells with high performance, showing significant potential in flexible energy storage devices. © 2012 American Chemical Society. Source


Liu R.,Harbin Institute of Technology
Optics Communications | Year: 2014

We investigate the spontaneous emission properties of a five-level atom driven by a microwave field, where the two transitions are coupled to a double-band photonic-band-gap reservoir. The effects of the band-edge positions and the Rabi frequency of the microwave field on the emission spectrum are discussed. It is found that several interesting phenomena in spontaneous emission spectra such as spectral-line enhancement, spectral-line elimination, and fluorescence quenching can be controlled simply by adjusting the Rabi frequency of the driving field and the transition frequency detunings from band edges. These phenomena originate from quantum interference induced by band-edge modes and the driving field. © 2014 Elsevier B.V. Source


Eight titanium complex greases (i.e., benzoic acid/stearic acid and sebacic acid/stearic acid titanium complex greases, and greases containing PTFE, or nano-titanium dioxide, or nano-silicon dioxide) were synthesized using 3-L reaction vessel. Their physical characteristics were characterized and their tribological properties were evaluated by using a four-ball tester. Chemical compositions of the boundary films generated on worn surfaces were analyzed with the use of scanning electron microscope and X-ray photoelectron spectrometer. Results show titanium complex greases containing PTFE, or nano-titanium dioxide, or nano-silicon dioxide exhibited excellent tribological performance. The mechanism for the friction-reduction and antiwear effect of all titanium complex greases was also proposed and discussed from a tribochemistry point of view. © 2010 Springer Science+Business Media, LLC. Source


Pan J.-S.,Harbin Institute of Technology | Lee C.-Y.,Lunghwa University of Science and Technology | Meher P.K.,Institute for Infocomm Research
IEEE Transactions on Circuits and Systems I: Regular Papers | Year: 2013

For cryptographic algorithms, such as elliptic curve digital signature algorithm (ECDSA) and pairing algorithm, the crypto-processors are required to perform large number of additions and multiplications over finite fields of large orders. To have a balanced trade-off between space complexity and time complexity, in this paper, novel digit-serial and digit-parallel systolic structures are presented for computing multiplication over GF(2{m}). Based on novel decomposition algorithm, we have derived an efficient digit-serial systolic architecture, which involves latency of O(\sqrt{m/d}) clock cycles, while the existing digit-serial systolic multipliers involve at least O(m/d) latency for digit-size d. The proposed digit-serial design could be used for AESP-based fields with the same digit-size as the case of trinomial-based fields with a small increase in area. We have also proposed digit-parallel systolic architecture employing n-term Karatsuba-like method, where the latency can be reduced from O(\sqrt{m/d}) to O(\sqrt{m/nd}). This feature would be a major advantage for implementing multiplication for the fields of large orders. From synthesis results, it is shown that the proposed architectures have significantly lower time complexity, lower area-delay product, and higher bit-throughput than the existing digit-serial multipliers. © 2013 IEEE. Source


Feng Y.,Harbin Institute of Technology | Feng Y.,RMIT University | Yu X.,RMIT University | Han F.,RMIT University
Automatica | Year: 2013

This paper proposes a method to overcome the singularity problem of terminal sliding-mode control systems. The system behaviors in both the reaching phase and the ideal sliding-mode are analyzed. A global nonsingular terminal sliding-mode control strategy for nonlinear systems is developed and it is shown that the proposed control strategy can eliminate the singularity, while guaranteeing the finite-time reachability of the systems to the terminal sliding-mode surface and the finite-time convergence of the systems towards the origin along the terminal sliding-mode surface. © 2013 Elsevier Ltd. All rights reserved. Source


Wu L.,Harbin Medical University | Wang Z.,Harbin Institute of Technology | Shen B.,Harbin Medical University
Nanoscale | Year: 2013

Large scale and well-ordered gold nanoparticle superlattices were fabricated by self-assembly as an active substrate for surface-enhanced Raman scattering (SERS) that can quantitatively detect carbaryl with a detection limit of 1 ppm. These fabricated superlattices with a dimension of several hundred micrometers exhibited high, reproducible SERS activity. © 2013 The Royal Society of Chemistry. Source


Wang Y.,Harbin Institute of Technology
Journal of Materials Research | Year: 2015

A three-dimensional nanostructured graphene oxide-Mn3O4 hybrid was synthesized by a coprecipitation method and used as an anode material of lithium ion batteries, which reached an initial specific capacity of 1400 mA h/g. This method was developed to simplify the process of fabricating uniform composite nanomaterials for abundant applications. In this work, Mn3O4 particles were coordinately distributed on the surface of reduced graphene oxide nanosheets to avoid detrimental stacking of graphene layers by forming 3D nanostructures, as characterized by a scanning electron microscope. As demonstrated by the in situ observation of a scanning probe microscope, severe pulverization of Mn3O4 particles during charge/discharge processing was significantly abstained when graphene layers constrained swelling and shrinkage. The as-prepared graphene-Mn3O4 nanomaterials exhibited a large specific capacity of 949 mA h/g, high-rechargeable efficiency of ∼98%, and exceptional cyclic stability. After 100 constant-current charging/discharging cycles at 100 mA/g, the specific capacity remained at 792 mA h/g with a coulombic efficiency of 98.1%. Furthermore, the coprecipitation method proposed in this work provides a strategy to fabricate other nanostructured composites for different kinds of applications. Copyright © Materials Research Society 2015. Source


Chen S.,Harbin Institute of Technology | Shi J.,College of William and Mary
Nonlinear Analysis: Real World Applications | Year: 2013

In this work we investigate a diffusive Gierer-Meinhardt system with gene expression time delays in the production of activators and inhibitors, and also a saturation in the activator production, which was proposed by Seirin Lee et al. (2010) [10]. We rigorously consider the basic kinetic dynamics of the Gierer-Meinhardt system with saturation. By using an upper and lower solution method, we show that when the saturation effect is strong, the unique constant steady state solution is globally attractive despite the time delays. This result limits the parameter space for which spatiotemporal pattern formation is possible. © 2012 Elsevier Ltd. All rights reserved. Source


Tandem reactions of Barbier-type allylation, Brook rearrangement and fluoride-promoted aldol reaction were developed, which afforded a facile, "one-pot" process to β-hydroxy-α,α-difluoroketone derivatives with good to excellent yields. © 2011 Elsevier B.V. All rights reserved. Source


Ni W.,Nanchang University | Wang X.,Harbin Institute of Technology | Xiong C.,Nanchang University
Automatica | Year: 2013

This paper considers, for leader-following linear multi-agent systems (MAS) connected by switching graphs, the consensus controllability and observability, and extends the existing results which are valid only for fixed graph case. Unlike the general controllability and observability problems which require each state to be controllable and observable, we only examine the consensus state to be controllable and the tracking error states between the followers and the leader to be observable. As for the consensus controllability, the admissible control input for each follower agent can only obtain relative and local information from its neighbors, and the control objective is to render the MAS to achieve consensus, in the sense of convergence of each follower's state to that of a leader agent. As for the consensus observability, the output of the MAS is the information-flow in the multi-agent network, and the observation task is to reconstruct the tracking error states between the followers and the leader. It is demonstrated in this paper that the controllability and observability of each individual system and the jointly connected switching topology (including fixed topology as a special case) jointly imply the consensus controllability and observability of the MAS. The consensus controllability property is used in the robust leader-following consensus problem, and the consensus observability property is used in the robust observer-based leader-following consensus problem, both under switching topology. © 2013 Published by Elsevier Ltd. Source


Kar S.,Harbin Institute of Technology | Ho Y.K.,Academia Sinica, Taiwan
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

We have investigated the doubly excited 1,3Pe resonance states of helium and the hydrogen negative ion interacting with Coulomb and screened Coulomb potentials using exponential correlated wave functions. In the pure Coulomb case, calculations have been carried out by using the complex-coordinate rotation and the stabilization method. The 1Pe resonance states of He below the N= 3, 4, and 5 thresholds of He+, and the 3Pe resonance states of He below the N= 3 thresholds of He+, are reported. The 5p2 3Pe state, which has attracted recent interest, is also reported and discussed. In the screened Coulomb case, we have used the stabilization method to obtain two different series (3pnp and 3dnd) of resonance states below the N= 3 He + threshold as a function of the screening parameters. Resonance widths for the 3dnd series show some interesting behaviors. The resonance parameters (position and width) for helium and the hydrogen negation ion as functions of the screening parameters are reported. © 2011 American Physical Society. Source


Mei J.,Nanjing Southeast University | Xiao B.,University of Tennessee at Knoxville | Shen K.,Harbin Institute of Technology | Tolbert L.M.,University of Tennessee at Knoxville | Zheng J.Y.,Nanjing Southeast University
IEEE Transactions on Power Electronics | Year: 2013

This paper proposed an improved phase disposition pulse width modulation (PDPWM) for a modular multilevel inverter which is used for Photovoltaic grid connection. This new modulation method is based on selective virtual loop mapping, to achieve dynamic capacitor voltage balance without the help of an extra compensation signal. The concept of virtual submodule (VSM) is first established, and by changing the loop mapping relationships between the VSMs and the real submodules, the voltages of the upper/lower arm's capacitors can be well balanced. This method does not requiring sorting voltages from highest to lowest, and just identifies the MIN and MAX capacitor voltage's index which makes it suitable for a modular multilevel converter with a large number of submodules in one arm. Compared to carrier phase-shifted PWM (CPSPWM), this method is more easily to be realized in field-programmable gate array and has much stronger dynamic regulation ability, and is conducive to the control of circulating current. Its feasibility and validity have been verified by simulations and experiments. © 1986-2012 IEEE. Source


Qu M.,Hong Kong Polytechnic University | Xia L.,Hong Kong Polytechnic University | Deng S.,Hong Kong Polytechnic University | Jiang Y.,Harbin Institute of Technology
Applied Energy | Year: 2012

When an air source heat pump (ASHP) operates in heating mode, frost can be accumulated on the surface of its finned outdoor coil. Frosting deteriorates the operation and energy efficiency of the ASHP and periodic defrosting becomes necessary. Currently the most widely used standard defrosting method for ASHPs is reverse cycle defrost. On the other hand, electronic expansion valves (EEVs) are commonly used in heat pump/refrigeration systems, including ASHP units, as throttle regulators of refrigerant flow. This paper reports on an experimental investigation of the performance of a reverse cycle defrost operation for a 6.5. kW experimental heating capacity residential ASHP whose outdoor coil had four-parallel refrigerant circuits, and with an EEV as the refrigerant flow throttle regulator. The detailed descriptions of the experimental ASHP unit and the experimental procedures of ASHP are firstly presented. This is followed by reporting the comparative experiments of two control strategies for the EEV to investigate their effects on defrosting performance: the EEV being fully open and the EEV being regulated by a degree of refrigerant superheat (DS) controller. Experimental results revealed that when the EEV was regulated by the DS controller during defrosting, a higher defrosting efficiency and less heat wastage would be resulted in. © 2011 Elsevier Ltd. Source


Wang B.,Northeast Forestry University | Li Y.,Northeast Forestry University | Ren N.,Harbin Institute of Technology
International Journal of Hydrogen Energy | Year: 2013

Though ethanol-type fermentation has many advantages for improving hydrogen production rate (HPR) in continuously mode hydrogen producing system, information on this fermentation is very deficient. The effect of hydraulic retention time (HRT) on biohydrogen production and operational stability of ethanol-type fermentation was investigated in a continuous stirred tank reactor (CSTR) using molasses as substrate. Five HRTs were examined, ranging from 4 to 10 h. At HRT 5 h, the highest HPR of 12.27 mmol L-1 h-1 was obtained from ethanol-type fermentation in the pH range of 4.3-4.4. During the whole operation process, ethanol, butyrate and acetate were the predominant metabolites. A total COD concentration of ethanol and acetate accounted for above 73.3% of total soluble microbial products. Linear regression showed that HPR and ethanol production rate were proportionately correlated at all HRTs which could be expressed as y = 0.9821x - 3.5151 (r2 = 0.9498). It is meaningful that the proposed recovery of both hydrogen and ethanol from fermentation process can improve energy production rate and economic profit. Results demonstrated that the best energy production rate was 15.50 kJ L -1 h-1, occurred at HRT = 5 h. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source


Yue F.,Beijing Institute of Technology | Zuo W.,Harbin Institute of Technology
Information Sciences | Year: 2014

A typical palmprint identification system identifies a query palmprint by matching it with the templates in the database and comparing the similarity score with a pre-defined threshold. However, continual database expansion would make conventional brute force search method inefficient for large-scale palmprint identification. In this paper, we propose a consistent orientation pattern (COP) hashing method to enforce fast search. Using the orientation and response features extracted by steerable filter, we first give an analysis on the consistency of orientation features, and then introduce a method to construct COP using the consistent features. Because the COP is very stable across the samples of the same subject, the COP hashing method can find the target template quickly and thus can lead to early termination of the searching process. Experiments have been carried out on several real and synthetic databases, and the results show that the COP hashing method can accelerate the identification process by more than an order of magnitude, and can achieve comparable identification accuracy while compared with the state-of-the-art approaches. © 2013 Elsevier Inc. All rights reserved. Source


Hu Q.,Harbin Institute of Technology
IET Control Theory and Applications | Year: 2010

A robust adaptive fault-tolerant control approach for attitude tracking of flexible spacecraft is proposed for use in situations when there are reaction wheels/actuator failures, external disturbances and time-varying inertia-parameter uncertainties. More specifically, a robust controller based on sliding-mode control scheme is first designed to ensure that the equilibrium point in the closed-loop system is uniform ultimate bounded stability, incorporating constraints on actuator failures, whose failure time instants, patterns and values are unknown, as motivated from a practical spacecraft control application. Then, this controller is redesigned such that an assumption on a bound required of the unknown and time-varying inertia matrix is released by using online estimation for this bound. The prescribed robust performance is also evaluated by L2-gain less than a given small level for the penalty output signal. Complete stability and performance analysis are presented, and illustrative simulation results of an application to flexible spacecraft show that the high precise attitudes control and vibration suppression are successfully achieved using various scenarios of control effect failures. © 2010 The Institution of Engineering and Technology. Source


Sun X.-M.,Dalian University of Technology | Wu D.,Dalian University of Technology | Liu G.-P.,Dalian University of Technology | Liu G.-P.,Harbin Institute of Technology | Wang W.,Dalian University of Technology
IEEE Transactions on Industrial Electronics | Year: 2014

The input-to-state stability (ISS) for a class of networked control systems with random delays and packet dropouts appearing simultaneously in both feedback and forward channels is thoroughly investigated in this paper. A new network predictive controller scheme is introduced in order to compensate the effect of transmission delays and packet dropouts. By making use of the small gain theorem, the stability criteria of the considered new system are derived. The proposed stability conditions are fairly easy to check and considerably less conservative than the existing ones. These criteria reveal that, if the original linear systems are controllable and observable, then, by adopting the proposed networked-predictive-control scheme, the ISS properties can be guaranteed for the overall system despite the effects of networking such as transmission bounded delays, packet dropouts, and possible disturbance inputs. When no disturbance inputs occur, the system stability can be guaranteed for random delays with a certain bound or else for any large constant delays. Results for two illustrative examples are given to validate the proposed control scheme, the second one being a laboratory-scale dc-motor rig. © 2013 IEEE. Source


Zhou B.,Harbin Institute of Technology | Lin Z.,University of Virginia
IEEE Transactions on Automatic Control | Year: 2014

This technical note is concerned with stabilization of polynomially unstable linear systems with multiple time-varying input delays. A truncated predictor feedback (TPF), which is obtained by truncating the distributed terms in the traditional predictor feedback, is proposed. The proposed TPF is a linear static partial state feedback with a time-varying feedback gain that is constructed from the steady solution to a class of parametric Lyapunov differential equations. Under the assumption that the open-loop system is only polynomially unstable and is uniformly controllable, it is shown that, for sufficiently small value of the design parameter, the resulting closed-loop system is exponentially stable no matter how large the time-varying delays are as long as they are bounded. Simulation demonstrates these theoretical results. © 1963-2012 IEEE. Source


Mei J.,Nanjing Southeast University | Shen K.,Harbin Institute of Technology | Xiao B.,University of Tennessee at Knoxville | Tolbert L.M.,University of Tennessee at Knoxville | And 2 more authors.
IEEE Transactions on Industrial Electronics | Year: 2014

This paper presents an improved phase disposition pulsewidth modulation (PWM) (PDPWM) for the modular multilevel converter (MMC) which is based on the selective loop bias mapping (SLBM) method. Its main idea is to change the bias of the PDPWM carrier wave cycling according to the balance situation of the system. This new modulation method can operate at symmetric condition to generate an output voltage with as many as 2N + 1 levels, and by SLBM, the voltages of the upper/lower arm capacitors can be well balanced. Compared to carrier phase-shifted PWM, this method is more easily to be realized and has much stronger dynamic regulation ability. Specially, this method has no issues of sorting, which makes it suitable for MMC with a large number of submodules in one leg. With simulation and experiments, the validity of the proposed method has been shown. © 1982-2012 IEEE. Source


Wu T.-Y.,Harbin Institute of Technology | Tseng Y.-M.,National Changhua University of Education | Tsai T.-T.,National Changhua University of Education
Computer Networks | Year: 2012

Authenticated group key exchange (AGKE) protocol provides secure group communications for participants in cooperative and distributed applications over open network environments such as the Internet and wireless networks. In the past, a number of AGKE protocols based on the identity (ID)-based public key system (IDPKS) have been proposed, called ID-AGKE protocols. In the IDPKS system, users' identities are viewed as the public keys to eliminate certificate management of the traditional certificate-based public key system. Nevertheless, any certificate-based public key systems or IDPKS systems must provide a revocation mechanism to revoke misbehaving/compromised users from the public key systems. However, there was little work on studying the revocation problem of the IDPKS system. Quite recently, Tseng and Tsai presented a new ID-based encryption scheme and its associated revocation mechanism to solve the revocation problem efficiently, called revocable ID-based public key system (R-IDPKS). In this paper, we follow Tseng and Tsai's R-IDPKS system to propose the first revocable ID-AGKE (RID-AGKE) protocol. Security analysis is made to demonstrate that the proposed RID-AGKE protocol is a provably secure AGKE protocol and can resist malicious participants. As compared to the recently proposed ID-AGKE protocols, the proposed RID-AGKE protocol is provably secure and has better performance while providing an efficient revocation mechanism. © 2012 Elsevier B.V. All rights reserved. Source


Alam M.M.,Harbin Institute of Technology | Meyer J.P.,University of Pretoria
Journal of Fluids and Structures | Year: 2013

This paper comprises an in-depth physical discussion of the flow-induced vibration of two circular cylinders in view of the time-mean lift force on stationary cylinders and interaction mechanisms. The gap-spacing ratio T/. D is varied from 0.1 to 5 and the attack angle α from 0° to 180° where T is the gap width between the cylinders and D is the diameter of a cylinder. Mechanisms of interaction between two cylinders are discussed based on time-mean lift, fluctuating lift, flow structures and flow-induced responses. The whole regime is classified into seven interaction regimes, i.e., no interaction regime; boundary layer and cylinder interaction regime; shear-layer/wake and cylinder interaction regime; shear-layer and shear-layer interaction regime; vortex and cylinder interaction regime; vortex and shear-layer interaction regime; and vortex and vortex interaction regime. Though a single non-interfering circular cylinder does not correspond to a galloping following quasi-steady galloping theory, two circular cylinders experience violent galloping vibration due to shear-layer/wake and cylinder interaction as well as boundary layer and cylinder interaction. A larger magnitude of fluctuating lift communicates to a larger amplitude vortex excitation. © 2013 Elsevier Ltd. Source


Zhao B.,Georgia Institute of Technology | Zhao J.M.,Harbin Institute of Technology | Zhang Z.M.,Georgia Institute of Technology
Journal of the Optical Society of America B: Optical Physics | Year: 2015

It has been demonstrated recently that metal gratings can significantly improve the near-infrared absorptance of graphene from 0.023 to nearly 0.70 because of the excitation of magnetic polaritons (MPs). In the present study, it is shown that the absorptance of graphene can be further enhanced to more than 0.80 by surface plasmon polaritons (SPPs) enabled by the grating. Meanwhile, graphene behaves as a sheet resistor that is able to boost the absorption when MPs or SPPs are excited without changing their resonance frequencies or dispersion relations. The effects of higher-order MPs, as well as the grating geometry on the enhanced absorptance, are also examined. Rigorous coupled-wave analysis (RCWA) is employed to calculate the radiative properties and power dissipation density in both the graphene and the metal grating. This study will facilitate the understanding of the coupling phenomena between graphene and nanostructures and may also benefit the design of next-generation graphenebased optical and optoelectronic devices. © 2015 Optical Society of America. Source


Liu M.,Huaiyin Normal University | Wang K.,Harbin Institute of Technology
Journal of Nonlinear Science | Year: 2013

In this paper, we propose and investigate a stochastic two-prey one-predator model. Firstly, under some simple assumptions, we show that for each species x i, i=1,2,3, there is a π i which is represented by the coefficients of the model. If π i <1, then x i goes to extinction (i.e., lim t→+∞ x i (t)=0); if π i >1, then x i is stable in the mean (i.e., limt→+∞t-1 ∫0 txi(s), ds=a positive constant). Secondly, we prove that there is a stationary distribution to this model and it has the ergodic property. Thirdly, we establish the sufficient conditions for global asymptotic stability of the positive solution. Finally, we introduce some numerical simulations to illustrate the theoretical results. © 2013 Springer Science+Business Media New York. Source


Pan Y.,Harbin Institute of Technology | Pan Y.,Michigan State University | Pratt S.,Michigan State University
Physical Review C - Nuclear Physics | Year: 2014

The role of baryon-antibaryon annihilation during the hadronic stage of a relativistic heavy ion collision is explored by simulating the chemical evolution of a hadron gas. Beginning with a chemically equilibrated gas at an initial temperature of 170 MeV, the chemical composition of a representative hydrodynamic cell is followed throughout the hadronic stage. The cell's volume changes with time according to a parametrization that mimics a three-dimensional hydrodynamic expansion. The chemical evolution includes both annihilation and regeneration of baryons, consistent with detailed balance. During the hadronic stage, the number of baryons drops by approximately 40% for the case in which there is no net baryonic charge. When the calculations are performed without the baryon regenerating processes, e.g., 5π→pp̄, the loss of baryons was found to be closer to 50%. After accounting for annihilation, yields are consistent with measurements from the ALICE Collaboration at the Large Hadron Collider (LHC). Baryon annihilation is shown to alter the extracted chemical breakup temperature by significantly changing the p/π ratio. Assuming that annihilation cross sections are independent of the strangeness and isospin of the annihilating baryon and antibaryon, the loss of strange baryons from annihilation is found to be similar. © 2014 American Physical Society. Source


Jiang J.J.,Peking University | Ye B.,Harbin Institute of Technology | Ma X.M.,Peking University
Energy Policy | Year: 2014

The Shenzhen ETS is the first urban-level "cap-and-trade" carbon emissions trading scheme to operate in China. This paper gives an overview of the economic and emissions situation in Shenzhen and focuses on the development of the Shenzhen ETS regulatory framework. It is devised as an ETS with an intensity-based cap, output-based allocation and a market for trading of allowances. The design of the Shenzhen ETS attaches great importance to coordinate the dynamic relationships between economic growth, industrial transition and emissions control. The cap and its allocation are determined by carbon intensity reduction targets and economic output, with an aim to slow down emissions growth while mitigating shocks from economic fluctuation and industrial adjustment to market stability. The Shenzhen ETS features extensive coverage consisting of three types of regulated entities and four categories of covered emissions, in order to control carbon emissions by both improving energy efficiency and restraining growing energy demand. A competitive game theory method is created for allocation of free allowances to manufacturing enterprises. Mechanisms for carbon offsets and market stabilization are developed to promote active and orderly trading in the carbon market. Moreover, several challenges and their policy choices are detailed for the development of the Shenzhen ETS. © 2014 Elsevier Ltd. Source


Li X.,Harbin Institute of Technology | Gao H.,Bohai University
Automatica | Year: 2013

This paper is concerned with the problem of robust finite frequency (FF) H∞ filtering for uncertain twodimensional (2-D) discrete-time systems in the Fornasini-Marchesini local state-space (FM LSS) model with polytopic uncertain parameters. The goal of the paper is to design filters such that the FF H∞ norm of the filtering error system has a specified upper bound for all uncertainties. In light of a recently developed generalized bounded real lemma, a linear matrix inequality-based approach is proposed for robust FF H∞ filter analysis and design. It is demonstrated that the presented approach to robust FF H∞ filter design covers the latest standard H∞ filtering result. Moreover, it is shown that the existing results specialized for the Roesser model, when applied to the FM LSS model through a model transformation, are much more restrictive than the proposed results in the paper, further justifying this work. © 2013 Elsevier Ltd. All rights reserved. Source


Chen Y.-H.,Fuzhou University | Xia Y.,Fuzhou University | Chen Q.-Q.,Fuzhou University | Song J.,Harbin Institute of Technology
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2015

The Lewis-Riesenfeld phases which play a crucial role in constructing shortcuts to adiabaticity may be a resource for the implementation of quantum phase gates. By combining "Lewis-Riesenfeld invariants" with "quantum Zeno dynamics," we propose an effective scheme of rapidly implementing π phase gates via constructing shortcuts to adiabatic passage in a two-distant-atom-cavity system. The influence of various decoherence processes such as spontaneous emission and photon loss on the fidelity is discussed. It is noted that this scheme is insensitive to both error sources. Additionally, a creation of N-atom cluster states is put forward as a typical example of the applications of the fast and noise-resistant phase gates. The study results show that the shortcuts idea is not only applicable in other logic gates with different systems, but also propagable for many quantum information tasks. © 2015 American Physical Society. Source


Zhang D.,Harbin Institute of Technology | Johnson E.A.,University of Southern California
Structural Control and Health Monitoring | Year: 2013

A substructure identification method for shear structures is proposed herein. A shear structure is partitioned into many simple substructures; an inductive identification procedure is derived to estimate the structural parameters from top to bottom. In each identification step, the dynamic equilibrium of a one-floor substructure is utilized to construct a substructure identification problem, estimating the story stiffness and damping coefficient. An identification error analysis for least-square error identification problems, based on the linearization of the least-square error problem, is proposed and applied to the substructure identification method. The results show that the identification errors are closely related to two important structural responses: the frequency response of the interstory acceleration of the identified story and the frequency response ratio between adjacent interstory accelerations. Further, these responses are critical to the substructure identification only near a certain frequency, the substructure natural frequency of the identified story substructure. The larger the first response is and/or the smaller the second response is, the more accurate the estimation results will be. A numerical example of a five-story shear structure is given to demonstrate the effectiveness of the proposed substructure identification method and to verify the identification error analysis results. From the results of the identification error analysis, a companion paper proposes a controlled substructure identification method, utilizing specially designed algorithms for structural control devices to change the two key structural responses that affect the identification accuracy, to improve the accuracy of the substructure identification. Copyright © 2012 John Wiley & Sons, Ltd. Source


Wang B.-L.,Harbin Institute of Technology
Acta Mechanica Sinica/Lixue Xuebao | Year: 2013

This paper studies the fracture behavior of a thermoelastic cylinder subjected to a sudden temperature change on its outer surface within the framework of non-classical heat conduction. The heat conduction equation is solved by separation of variable technique. Closed form solution for the temperature field and the associated thermal stress are established. The critical parameter governing the level of the transient thermal stress is identified. Exact expression for the transient stress intensity factor is obtained for a crack in the cylinder. The difference between the non-classical solutions and the classical solution are discussed. It is found that the traditional classical heat conduction considerably underestimates the transient thermal stress and thermal stress intensity factor. © 2013 The Chinese Society of Theoretical and Applied Mechanics; Institute of Mechanics, Chinese Academy of Sciences and Springer-Verlag Berlin Heidelberg. Source


Liu M.,Harbin Institute of Technology | Shi P.,University of South Wales | Shi P.,Victoria University of Melbourne | Shi P.,University of Adelaide
Automatica | Year: 2013

This paper investigates the problem of fault estimation and fault-tolerant control against sensor failures for a class of nonlinear Itô stochastic systems with simultaneous input and output disturbances. By using a new descriptor sliding mode approach, an accurate estimation of the system states, fault vector and disturbances can be obtained simultaneously. Based on the state estimates, an integral-type sliding mode control scheme against faults and disturbances is proposed to stabilize the resulting fault system. It is shown that the reachabilities of the proposed sliding mode surfaces can be guaranteed in both the state estimate space and the estimation error space simultaneously under the designed control schemes. Finally, a numerical example is presented to illustrate the effectiveness and applicability of the proposed technique. © 2013 Elsevier Ltd. All rights reserved. Source


Jing D.,Ohio State University | Jing D.,Harbin Institute of Technology | Bhushan B.,Ohio State University
Langmuir | Year: 2013

Reduction of fluid drag is important in the micro-/nanofluidic systems. Surface charge and boundary slip can affect the fluid drag, and surface charge is also believed to affect boundary slip. The quantification of surface charge and boundary slip at a solid-liquid interface has been widely studied, but there is a lack of understanding of the effect of surface charge on boundary slip. In this paper, the surface charge density of borosilicate glass and octadecyltrichlorosilane (OTS) surfaces immersed in saline solutions with two ionic concentrations and deionized (DI) water with different pH values and electric field values is quantified by fitting experimental atomic force microscopy (AFM) electrostatic force data using a theoretical model relating the surface charge density and electrostatic force. Results show that pH and electric field can affect the surface charge density of glass and OTS surfaces immersed in saline solutions and DI water. The mechanisms of the effect of pH and electric field on the surface charge density are discussed. The slip length of the OTS surface immersed in saline solutions with two ionic concentrations and DI water with different pH values and electric field values is measured, and their effects on the slip length are analyzed from the point of surface charge. Results show that a larger absolute value of surface charge density leads to a smaller slip length for the OTS surface. © 2013 American Chemical Society. Source


Li X.,Beijing Jiaotong University | Li J.H.,Harbin Institute of Technology | Zhang L.M.,Hong Kong University of Science and Technology
Computers and Geotechnics | Year: 2014

Experimental evidence shows that a gap-graded soil or a widely-graded granular material may have a bimodal soil-water characteristic curve (SWCC) and a bimodal permeability function. A bimodal SWCC or a bimodal permeability function originates from a dual-porosity structure. To date, the prediction of bimodal SWCCs for gap-graded soils is still a difficult task. In this paper, a bimodal SWCC model is proposed to describe the drying process of granular soils considering a dual-porosity structure. The new SWCC model shows powerful capability in fitting the SWCCs for soils varying from gravel to silt. Regression analysis is conducted to establish empirical relations between the model parameters and the indexes of soil grain-size distribution (GSD). Based on these relations, the new model predicts well both the bimodal SWCCs for gap-graded soils and the unimodal SWCCs for well-graded soils and uniform soils. A bimodal permeability function is also proposed and linked to the new SWCC model. In the absence of experimental SWCCs and permeability functions, the new model can be used to obtain preliminary SWCCs and permeability functions for granular soils. It should be mentioned that the prediction of the SWCC from the GSD is still empirical and does not address the cyclic wetting/drying process. Measurement of the SWCC should be performed wherever an accurate SWCC is required. © 2014 Elsevier Ltd. Source


Zhang B.,Harbin Institute of Technology
International Journal of Systems Science | Year: 2010

The problem of infinite eigenvalue assignment in the descriptor system [image omitted] via state feedback control u = Kx is considered. The problem is related to a group of recursive equations. By proposing a general complete parametric solution to this group of recursive equations, a general complete parametric approach is presented for the proposed infinite eigenvalue assignment problem. General parametric forms of the closed-loop eigenvectors and the feedback gain matrix are given in terms of certain parameter vectors which represent the design degrees of freedom. The approach involves mainly a singular value decomposition of the matrix E and a singular value decomposition of a lower dimension matrix, and thus is very simple and requires less computational work. Moreover, it overcomes the defects of some previous works. An example is given to illustrate the effect of the approach. © 2010 Taylor & Francis. Source


Gao H.,Harbin Institute of Technology | Fei Z.,Washington University in St. Louis | Lam J.,University of Hong Kong | Du B.,University of Hong Kong
IEEE Transactions on Automatic Control | Year: 2011

This technical note studies the problem of exponential estimates for Markovian jump systems with mode-dependent interval time-varying delays. A novel LyapunovKrasovskii functional (LKF) is constructed with the idea of delay partitioning, and a less conservative exponential estimate criterion is obtained based on the new LKF. Illustrative examples are provided to show the effectiveness of the proposed results. © 2010 IEEE. Source


Tronchetti F.,Harbin Institute of Technology
Space Policy | Year: 2011

Preventing the weaponization of outer space is one of the most relevant issues of the current space law debate. In recent years discussions on this issue have significantly increased in international fora, such as the UN Conference on Disarmament and the COPUOS. While it has not been possible to arrive at an agreed solution on how to efficiently deal with the problem of possible weaponization of outer space so far, several valuable proposals have been put forward. China and Russia, on the one side, and the European Union, on the other, have taken the lead in this respect. While the former have submitted a proposal for a draft treaty on the demilitarization of outer space, known as the PPWT, the latter has issued a Draft Code of Conduct for Outer Space Activities. Despite the differences between the two proposals, this paper proposes the development of a Chinese, Russian and European common approach aimed at preventing the weaponization of outer space. Although such a goal is undoubtedly challenging, some political and legal factors may enable such cooperation in the not-too-distant future. © 2011 Elsevier Ltd. Source


Chen Y.,Beijing Computational Science Research Center | Zhang B.,Harbin Institute of Technology
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

We investigate high-order harmonic generation (HHG) from asymmetric molecules exposed to intense laser fields. We show that the emissions of odd and even harmonics depend differently on the orientation angle, the internuclear distance, as well as the effective charge. This difference mainly comes from different roles of intramolecular interference in the HHG of odd and even harmonics. These roles map the structure of the asymmetric molecule to the odd vs even HHG spectra. © 2011 American Physical Society. Source


Yang X.,Harbin Institute of Technology | Xing X.,Bohai University
Journal of the Franklin Institute | Year: 2014

This paper is concerned with the identification problem of linear parameter varying (LPV) time-delay systems. Due to inherent nonlinearity, the industrial processes are often approximately described by an LPV model constructed by synthesizing multiple local models. Time-delay is commonly experienced in industrial processes and it can be parameter varying or constant in the process model. The multiple model identification of LPV systems with parameter varying or constant time-delay is formulated in the scheme of the expectation-maximization (EM) algorithm and the parameter varying property and the time-delay property of the process are handled simultaneously. The irrigation channel example and high purity distillation column example are used to present the effectiveness of the proposed method. © 2014 The Franklin Institute. Source


Wu L.,Harbin Institute of Technology | Ho D.W.C.,City University of Hong Kong | Li C.W.,City University of Hong Kong
Systems and Control Letters | Year: 2011

This paper is concerned with the sliding mode control (SMC) of a continuous-time switched stochastic system. A sufficient condition for the existence of reduced-order sliding mode dynamics is derived and an explicit parametrization of the desired sliding surface is also given. Then, a sliding mode controller is then synthesized for reaching motion. Moreover, the observer-based SMC problem is also investigated. Some sufficient conditions are established for the existence and the solvability of the desired observer and the observer-based sliding mode controller is synthesized. Finally, numerical examples are provided to illustrate the effectiveness of the proposed theory. © 2011 Elsevier B.V. All rights reserved. Source


Liu Z.,Harbin Institute of Technology
Electronics Letters | Year: 2014

A simple method for dynamically adjusting the tap-length adaptation step-size of a variable tap-length linear equaliser based on the fractional tap-length algorithm is presented. Simulations show that the technique provides a fast convergence of tap-length and small steady-state tap-length fluctuation. © The Institution of Engineering and Technology 2014. Source


Hu Q.,Harbin Institute of Technology
Transactions of the Institute of Measurement and Control | Year: 2012

This paper is concerned with the development of a control system for rotational manoeuvre and vibration suppression of a flexible spacecraft. The design approach presented here treats the problem of spacecraft attitude control separately from the elastic vibration suppression problem. As a stepping stone, a state feedback sliding mode control command is designed to achieve the reference trajectory tracking control of attitude angle. This is followed by the design of an adaptive sliding mode control law using only output for robust stabilization of spacecraft in the presence of parametric uncertainty and external disturbances. Even if this controller has the ability to reject the disturbance and deal with uncertainty, it excites the elastic modes of flexible appendages. The undesirable vibration is then actively suppressed by applying feedback control voltages to the piezoceramic actuators, in which the modal velocity feedback control method is adopted here for determining the control voltages. The effectiveness of the control schemes in handling external disturbance and uncertainty in the system parameters is also studied. Both analytical and numerical results are presented to show the theoretical and practical merit of this hybrid approach. © The Author(s) 2011. Source


Feng Y.,Harbin Institute of Technology | Yu X.,RMIT University | Han F.,RMIT University
IEEE Transactions on Industrial Electronics | Year: 2013

This paper proposes a terminal sliding-mode (TSM) observer for estimating the immeasurable mechanical parameters of permanent-magnet synchronous motors (PMSMs) used for complex mechanical systems. The observer can track the system states in finite time with high steady-state precision. A TSM control strategy is designed to guarantee the global finite-time stability of the observer and, meanwhile, to estimate the mechanical parameters of the PMSM. A novel second-order sliding-mode algorithm is designed to soften the switching control signal of the observer. The effect of the equivalent low-pass filter can be properly controlled in the algorithm based on requirements. The smooth signal of the TSM observer is directly used for the parameter estimation. The experimental results in a practical CNC machine tool are provided to demonstrate the effectiveness of the proposed method. © 1982-2012 IEEE. Source


Ding S.X.,University of Duisburg - Essen | Zhang P.,Rhine-Waal University of Applied Sciences | Yin S.,Harbin Institute of Technology | Ding E.L.,Gelsenkirchen University of Applied Sciences
IEEE Transactions on Industrial Informatics | Year: 2013

In this paper, a design framework of fault-tolerant wireless networked control systems (NCSs) is developed for industrial automation applications. The main objective is to achieve an integrated parameterization and design of the communication protocols, the control and fault diagnosis algorithms aiming at meeting high real-time requirements in industrial applications. To illustrate the design framework, a laboratory wireless fault-tolerant NCS platform is presented. © 2005-2012 IEEE. Source


Wu A.-C.,Harbin Institute of Technology
Journal of Statistical Mechanics: Theory and Experiment | Year: 2014

Recent empirical analyses of some realistic dynamical networks have demonstrated that their degree distributions are stable scale-free (SF), but the instantaneous well-connected hubs at one point of time can quickly become weakly connected. Motivated by these empirical results, we propose a simple toy dynamical agent-to-agent contact network model, in which each agent stays at one node of a static underlay network and the nearest neighbors swap their positions with each other. Although the degree distribution of the dynamical network model at any one time is equal to that in the static underlay network, the numbers and identities of each agent's contacts will change over time. It is found that the dynamic interaction tends to suppress epidemic spreading in terms of larger epidemic threshold, smaller prevalence (the fraction of infected individuals) and smaller velocity of epidemic outbreak. Furthermore, the dynamic interaction results in the prevalence to undergo a phase transition at a finite threshold of the epidemic spread rate in the thermodynamic limit, which is in contradiction to the absence of an epidemic threshold in static SF networks. Some of these findings obtained from heterogeneous mean-field theory are in good agreement with numerical simulations. © 2014 IOP Publishing Ltd and SISSA Medialab srl. Source


Wang X.,Harbin Institute of Technology | Hong Y.,CAS Academy of Mathematics and Systems Science | Huang J.,Chinese University of Hong Kong | Jiang Z.-P.,New York University
IEEE Transactions on Automatic Control | Year: 2010

In this note, the robust output regulation problem of a multi-agent system is considered. An internal model based distributed control scheme is adopted to achieve the objectives of asymptotic tracking and disturbance rejection in an uncertain multi-agent system where both the reference inputs and disturbances are generated by an exosystem. © 2006 IEEE. Source


Ding S.X.,University of Duisburg - Essen | Yin S.,Harbin Institute of Technology | Peng K.,University of Science and Technology Beijing | Hao H.,University of Duisburg - Essen | Shen B.,University of Duisburg - Essen
IEEE Transactions on Industrial Informatics | Year: 2013

In this paper, a data-driven scheme of key performance indicator (KPI) prediction and diagnosis is developed for complex industrial processes. For static processes, a KPI prediction and diagnosis approach is proposed in order to improve the prediction performance. In comparison with the standard partial least squares (PLS) method, the alternative approach significantly simplifies the computation procedure. By means of a data-driven realization of the so-called left coprime factorization (LCF) of a process, efficient KPI prediction, and diagnosis algorithms are developed for dynamic processes, respectively, with and without measurable KPIs. The proposed KPI prediction and diagnosis scheme is finally applied to an industrial hot strip mill, and the results demonstrate the effectiveness of the proposed scheme. © 2013 IEEE. Source


Zhou B.,Harbin Institute of Technology
Automatica | Year: 2014

This paper is concerned with stabilization of (time-varying) linear systems with a single time-varying input delay by using the predictor based delay compensation approach. Differently from the traditional predictor feedback which uses the open-loop system dynamics to predict the future state and will result in an infinite dimensional controller, we propose in this paper a pseudo-predictor feedback (PPF) approach which uses the (artificial) closed-loop system dynamics to predict the future state and the resulting controller is finite dimensional and is thus easy to implement. Necessary and sufficient conditions guaranteeing the stability of the closed-loop system under the PPF are obtained in terms of the stability of a class of integral delay operators (systems). Moreover, it is shown that the PPF can compensate arbitrarily large yet bounded input delays provided the open-loop (time-varying linear) system is only polynomially unstable and the feedback gain is well designed. Comparison of the proposed PPF approach with the existing results is well explored. Numerical examples demonstrate the effectiveness of the proposed approaches. © 2014 Elsevier Ltd. Source


Zhou B.,Harbin Institute of Technology
Automatica | Year: 2014

In this paper we consider the input delay compensation of linear systems with both state and input delays. Under the condition that the open-loop time-delay systems in the absence of input delay can be stabilized by (delayed) state feedback, a nested predictor based approach is established to predict the future states so that the delays in the input are compensated. It is shown that the compensated closed-loop system in the presence of input delay possesses the same characteristic equation as the closed-loop system in the absence of input delay. The proposed approach can be generalized to general linear systems having multiple state delays and/or multiple input delays. To implement the nested predictor based controllers by applying numerical integration approaches, an augmented nested predictor based approach by adding input filters is proposed. Two numerical examples are worked out to show the effectiveness of the proposed approach. © 2014 Elsevier Ltd. All rights reserved. Source


Yang J.,Nanjing University of Science and Technology | Chu D.,National University of Singapore | Zhang L.,Hong Kong Polytechnic University | Xu Y.,Harbin Institute of Technology
IEEE Transactions on Neural Networks and Learning Systems | Year: 2013

A sparse representation-based classifier (SRC) is developed and shows great potential for real-world face recognition. This paper presents a dimensionality reduction method that fits SRC well. SRC adopts a class reconstruction residual-based decision rule, we use it as a criterion to steer the design of a feature extraction method. The method is thus called the SRC steered discriminative projection (SRC-DP). SRC-DP maximizes the ratio of between-class reconstruction residual to within-class reconstruction residual in the projected space and thus enables SRC to achieve better performance. SRC-DP provides low-dimensional representation of human faces to make the SRC-based face recognition system more efficient. Experiments are done on the AR, the extended Yale B, and PIE face image databases, and results demonstrate the proposed method is more effective than other feature extraction methods based on the SRC. © 2012 IEEE. Source


Yuan X.,Northeast Forestry University | Gao D.,Northeast Forestry University | Gao D.,Harbin Institute of Technology
Journal of Hazardous Materials | Year: 2010

A sequencing batch reactor (SBR) with aerobic granular sludge was operated to determine the effect of different DO concentrations on biological nitrogen removal process and to investigate the spatial profiles of DO, ORP and pH as online control parameters in such systems. The results showed that DO concentration had a significant effect on nitrification efficiencies and the profiles of DO, ORP and pH. The specific nitrification rate was decreased from 0.0595mgNH4 +-N/(gMLSSmin) to 0.0251mgNH4 +-N/(gMLSSmin) after DO concentration was dropped off from 4.5mg/L to 1.0mg/L. High DO concentration improved the nitrification and increased the volumetric NH4 +-N removal. Low DO concentration enhanced TIN removal, while prolonged the nitrification duration. Also there existed a good correlation between online control parameters (ORP, pH) and nutrient (COD, NH4 +-N, NO2 --N, NO3 --N) variations in aerobic granular sludge reactor when DO was 2.5mg/L, 3.5mg/L and 4.5mg/L. However it was difficult to identify the end of nitrification and denitrification when DO was 1.0mg/L, due to no apparent bending points on ORP and pH curves. In conclusion, the optimal DO concentration was suggested at 2.5mg/L as it not only achieved high nitrogen removal efficiency and decreased the reaction duration, but also saved operation cost by aeration and mixing. © 2010. Source


Kaloop M.R.,Mansoura University | Li H.,Harbin Institute of Technology
Measurement: Journal of the International Measurement Confederation | Year: 2014

In this paper, RTK-GPS system was used for movement data collection. Two identification models namely; Multi input-single output (MISO) robust fit regression and Neural Network Auto-Regression Moving Average with eXogenous input (NNARMAX) models were used for the identification of these data. The analysis of test results indicate that: (1) the NNARMAX [4 4 1 1] and [5 4 1 5] models defined by taking into account the results of robust regression analysis estimate structural movements more accurately than the NNARMAX [0 1 0 0] model, and (2) the robust fit regression models have good capacities for mapping relationship of applied loads effects factors and displacements of tower. However, temperature and humidity effects on the entire modal shapes are insignificant and (3) the traffic loads are the main factor affects tower bridge displacement. © 2013 Elsevier Ltd. All rights reserved. Source


Chen X.,Nanjing University of Aeronautics and Astronautics | Chen X.,Xidian University | Chen H.-H.,National Cheng Kung University | Meng W.,Harbin Institute of Technology
IEEE Communications Surveys and Tutorials | Year: 2014

Cognitive Radio has been recognized as a promising way to improve spectrum efficiency of wireless communications by exploiting under-utilized licensed spectrum in temporal, frequency, and spatial domains. As a remedy to the limited capability of a single node or network, cooperative communication technique has a potential to further improve the performance of cognitive networks, especially for spectrum sensing based cognitive networks. Given that spectrum efficiency of a cognitive network is determined jointly by spectrum sensing and access capabilities, it makes sense to employ cooperative techniques to enhance their performance. This article offers a tutorial on various cooperative techniques in cognitive networks, with its emphasis on spectrum sensing and access based cooperation, interference constraint based adaptive cooperative feedback, rateless network coding based cooperative transmission, and limited cooperation based interference coordination. Finally, numerical results are given to showcase advantages of the proposed cooperative schemes for cognitive networks. © 2014 IEEE. Source


Ma K.-M.,Harbin Institute of Technology
Kongzhi yu Juece/Control and Decision | Year: 2013

For the large angle attitude control of large-scale spacecraft with uncertainties in the inertial matrices of spacecraft and the external disturbance torques, attitude tracking control laws are designed based on the higher-order sliding mode control technique. With the second-order sliding mode control used in the design, the robustness of the system with respect to uncertainties and external disturbances is improved, and the chattering phenomena are attenuated. For the designed controllers, numerical simulations are carried out, and compared with first-order sliding mode controllers. The simulation results show the effectiveness of the proposed method. Source


Kar S.,Harbin Institute of Technology | Ho Y.K.,Academia Sinica, Taiwan
Chemical Physics Letters | Year: 2011

The stability of the bound P and D states of the H2++ system, where the nuclei and the electron interact through a screened Coulomb (Yukawa-type) potential exp(-μr)/r, has been studied for different values of the screening parameters μ using correlated exponential wave functions in the framework of Ritz variational principle. The critical values of the screening parameters for the bound S, P and D states are reported for which H 2+ system is stable, while all the possible fragments are unbound, that is, it shows Borromean binding. © 2011 Elsevier B.V. All rights reserved. Source


Yin W.L.,Harbin Institute of Technology
Science China Technological Sciences | Year: 2010

The method for analyzing the deformation of flexible skin under the air loads was developed based on the panel method and finite element method. The deformation of flexible skin under air pressures and effects of the local deformation on the aerodynamic characteristics were discussed. Numerical results show that the flexible skin on the upper surface of trailing-edge will bubble under the air loads and the bubble has a powerful effect on the aerodynamic pressure near the surface of local deformation. Then the stiffness requirements for flexible skin of variable trailing-edge were given by using the Jacobs rule, i.e., the maximum displacement of skin is not greater than 0.1% of wing chord. Results show that the in-plane stiffness can be reduced by increasing the ratio of bending stiffness to in-plane stiffness. Although the deformation of flexible skin increases with the in-plane stiffness decreasing, it depends on the bending stiffness. When the bending stiffness exceeds critical value, the deformation of flexible skin only depends on the bending stiffness and has nothing to do with the in-plane stiffness. The conclusions can be used for the structural design of flexible skin. © Science China Press and Springer-Verlag Berlin Heidelberg 2010. Source


Cheung N.-M.,University of Southern California | Fan X.,Harbin Institute of Technology | Au O.,HKUST | Kung M.-C.,Applied Science and Technology Research Institute Company Ltd
IEEE Signal Processing Magazine | Year: 2010

In this article, we investigate using multi-core graphics processing units (GPUs) for video encoding and decoding. After an overview of video coding and GPUs, we review some previous work on structuring video coding modules so that the massive parallel processing capability of GPUs can be harnessed. We also review previous work on partitioning the video decoding flow between the central processing unit (CPU) and GPU. After that, we discuss in detail a GPU based fast motion estimation to illustrate some design considerations in using GPUs for video coding, and the tradeoff between speedup and rate-distortion performance. Our results highlight the importance to expose as much data parallelism as possible in designing algorithms for GPUs. © 2006 IEEE. Source


Lu H.,Harbin Institute of Technology
Journal of Applied Polymer Science | Year: 2012

A network of thermally responsive shape-memory polymers (SMPs) could imbibe a quantity of solvent molecules to swell, and subsequently induces a chemical potential change in polymer. When an equilibrium is reached between the mechanical load and the chemical potential of polymer network and solvent, the SMP polymer usually swells with a field of inhomogeneous and anisotropic deformation, which is considered to be equivalent to a hyperelastic field. We implement this theory in the free-energy function equation, and analyze examples of swelling-induced deformation and shape recovery behavior. This work may provide a powerful tool to study complex swelling-induced shape-memory behavior of SMPs in response to the immersing solvents. © 2011 Wiley Periodicals, Inc. Source


Liu M.,City University of Hong Kong | Liu M.,Harbin Institute of Technology | Ho D.W.C.,City University of Hong Kong | Niu Y.,East China University of Science and Technology
IEEE Transactions on Signal Processing | Year: 2010

This work is to investigate the problem of filter design for uncertain stochastic systems with mode-dependent quantized output measurements. The issues involved in this correspondence are output logarithmic quantization, Markovian jump parameters, It stochastic noise, and state noise. By employing an effective mathematical transformation, the quantization error of the output in the system equation is converted into a bounded nonlinearity. Based on the proposed model, a mode-dependent H∞ filter is designed, and sufficient conditions are established such that the filtering error system is robustly stochastically stable. A simulation example is presented to illustrate the effectiveness of the proposed approach. © 2010 IEEE. Source


Bian W.,Harbin Institute of Technology | Bian W.,Hong Kong Polytechnic University | Chen X.,Hong Kong Polytechnic University
IEEE Transactions on Neural Networks and Learning Systems | Year: 2012

In this paper, a smoothing neural network (SNN) is proposed for a class of constrained non-Lipschitz optimization problems, where the objective function is the sum of a nonsmooth, nonconvex function, and a non-Lipschitz function, and the feasible set is a closed convex subset of. Using the smoothing approximate techniques, the proposed neural network is modeled by a differential equation, which can be implemented easily. Under the level bounded condition on the objective function in the feasible set, we prove the global existence and uniform boundedness of the solutions of the SNN with any initial point in the feasible set. The uniqueness of the solution of the SNN is provided under the Lipschitz property of smoothing functions. We show that any accumulation point of the solutions of the SNN is a stationary point of the optimization problem. Numerical results including image restoration, blind source separation, variable selection, and minimizing condition number are presented to illustrate the theoretical results and show the efficiency of the SNN. Comparisons with some existing algorithms show the advantages of the SNN. © 2012 IEEE. Source


Hong Y.,CAS Academy of Mathematics and Systems Science | Wang X.,Harbin Institute of Technology | Jiang Z.-P.,New York University
International Journal of Robust and Nonlinear Control | Year: 2013

In this paper, distributed leader-follower control algorithms are presented for linear multi-agent systems based on output regulation theory and internal model principle. By treating a leader to be followed as an exosystem, the proposed framework can be used to generalize existing multi-agent coordination solutions to allow the identical agents to track an active leader with different dynamics and unmeasurable variables. Moreover, the obtained results for multi-agent coordination control are an extension of previous work on centralized and decentralized output regulation to a distributed control context. Necessary and sufficient conditions for the distributed output regulation problem are given. Finally, distributed output regulation of some classes of multi-agent systems with switching interconnection topologies are discussed via both static and dynamic feedback. Copyright © 2011 John Wiley & Sons, Ltd. Source


Yue X.,Harbin Institute of Technology | Dai Z.,Peking University
Advances in Colloid and Interface Science | Year: 2014

Liposomes have been extensively investigated as possible carriers for diagnostic or therapeutic agents due to their unique properties. However, liposomes still have not attained their full potential as drug and gene delivery vehicles because of their insufficient morphological stability. Recently, a super-stable and freestanding hybrid liposomal cerasome (partially ceramic- or silica-coated liposome) has drawn much attention as a novel drug delivery system because its atomic layer of polyorganosiloxane surface imparts higher morphological stability than conventional liposomes and its liposomal bilayer structure reduces the overall rigidity and density greatly compared to silica nanoparticles. Cerasomes are more biocompatible than silica nanoparticles due to the incorporation of the liposomal architecture into cerasomes. Cerasomes combine the advantages of both liposomes and silica nanoparticles but overcome their disadvantages so cerasomes are ideal drug delivery systems. The present review will first highlights some of the key advances of the past decade in the technology of cerasome production and then review current biomedical applications of cerasomes, with a view to stimulating further research in this area of study. © 2013 Elsevier B.V. Source