Wen J.,Foshan University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2016
Focusing on the problem of graph reachability query with keyword and distance constraint, a method of graph reachability query based on reference node embedding was proposed. Firstly, a very small part of representative reference nodes were selected from all nodes, shortest path distance between all nodes and these reference nodes were previously calculated. Next distance range was obtained based on the triangle inequality relation. Lastly according to the distance constraint and keyword in query condition, a conclusion of reachability could be drawn quickly. Comparative tests were done on data of social network and road network. Compared with Dijkstra algorithm, the proportion of drawing a reachability conclusion directly of the proposed algorithm is 84.6 % in the New York Road network, while 66.6 % in the Digital Bibliography & Library Project (DBLP) network, moreover, the running time are both shortened greatly, which is reduced by 87.4 % and 77.3 % respectively. The testing experimental data demonstrates that the computational complexity of online queries is reduced by using a small index cost through the method proposed in this paper, which is a good solution to graph reachability query with keyword and distance constraint suitable for weighted graph as well as unweighted graph, with wider value in application. © Springer International Publishing AG 2016.
Wu J.,Foshan University |
Sun Z.,CAS Academy of Mathematics and Systems Science
Automatica | Year: 2013
In this work, we investigate the observer-driven switching stabilization problem for a class of switched linear systems. By incorporating the switched observer presented in Sun, Wang, Xie, and Yu (2006) into the control loop, we construct an observer-driven path-wise switching law for the switched linear system. We prove that any stabilizable switched linear system is exponentially stable under the switching law, and establish a weak version of the separation principle for switching and observer design. © 2013 Elsevier Ltd. All rights reserved.
Huang Y.,Foshan University |
Yang L.-E.,Foshan University |
Luo Q.-Z.,Foshan University
Composites Part B: Engineering | Year: 2013
This paper presents a new approach for investigating the vibration behaviors of axially functionally graded Timoshenko beams with non-uniform cross-section. By introducing an auxiliary function, we can change the coupled governing equations with variable coefficients for the deflection and rotation to a single governing equation. Moreover, all physical quantities can be expressed in terms of the solution of the resulting equation. Making use of power series for unknown function, we can transform the single equation to a system of linear algebraic equations and will get a characteristic equation in natural frequencies for different boundary conditions. An advantage of the suggested approach is that the derived characteristic equation is a polynomial equation, where the lower and higher-order natural frequencies can be determined simultaneously from the multi-roots. Several examples of estimating natural frequencies for axially grade beams and non-uniform beams are presented, which show that our method has fast convergence and obtained numerical results have high accuracy. © 2012 Elsevier Ltd. All rights reserved.
Huang Y.,Foshan University |
Luo Q.-Z.,Foshan University |
Li X.-F.,Central South University
Composite Structures | Year: 2013
This paper studies the behavior of flexural waves traveling in carbon nanotubes (CNTs) in a free space and embedded in an elastic matrix. An exact higher-order model for analyzing dynamic behavior of nonlocal elastic beams with circular cross-section is proposed, where shear deformation and rotary inertia are both considered without introducing the shear correction factor. Moreover, traction-free condition at the beam surface is met. Using this model, wave dispersion of CNTs is studied and dispersion relation is obtained for single-walled and double-walled CNTs, respectively. Scale-dependent wave speed is given. The effectiveness and validity of the method are confirmed by comparing obtained numerical results with those based on molecular dynamics simulation, the nonlocal Euler-Bernoulli beam theory and nonlocal Timoshenko beam theory with stress gradient and strain gradient. The effects of the scale coefficient, the surrounding elastic medium and van der Waals force on the phase velocity are expounded. © 2012 Elsevier Ltd.
Kuang J.C.,Foshan University
Advanced Materials Research | Year: 2014
Nowadays the traditional dyeing wastewater treatments based on flocculation-biochemical technology become more difficult than before. The study in this paper aim was it to probe how adding rare earths (REs) into iron-carbon micro-electrolysis process to advance dyeing wastewater degradation. Firstly, the principle was discussed. Then the experimental methods were stated and it followed by exploring effect of iron powder size on the dye decolorization rate. Next were design of the micro electrolysis orthogonal experiments and discussion of influences of related factors on waste water treatment. The experimental results show that besides common iron powder particle size and the processing time, the factors that have great influence on dyeing wastewater treatment are Ce4+, pH, La3+ and iron/carbon ratio. The sequence of factors influence on wastewater micro-electrolysis treatment is Ce4+ > pH > La3+ > iron/carbon ratio. When pH is 6, COD removal rate arrives at maximum 89%, however when the pH is in the case of too high or too low, the effect of sewage degradation is not good. © (2014) Trans Tech Publications, Switzerland.
Chen J.,Foshan University
Computers and Mathematics with Applications | Year: 2011
We develop a multilevel augmentation method for solving nonlinear boundary value problems. We first describe the multilevel augmentation method for solving nonlinear operator equations of the second kind which has been proposed in our recent paper Chen et al. (2011) , and then apply it to solving the nonlinear two-point boundary value problems of second-order differential equations. The theoretical analysis of convergence order and computational complexity are proposed. Finally numerical experiments are presented to confirm the theoretical estimates and illustrate the efficiency of the method. © 2010 Elsevier Ltd. All rights reserved.
Chen J.,Foshan University
International Journal of Computer Mathematics | Year: 2012
In this study, we extend the multilevel augmentation method for Hammerstein equations established in Chen et al. [Fast multilevel augmentation methods for solving Hammerstein equations, SIAM J. Numer. Anal. 47 (2009), pp. 2321-2346] to solve nonlinear Urysohn integral equations. Under certain differentiability assumptions on the kernel function, we show that the method enjoys the optimal convergence order and linear computational complexity. Finally, numerical experiments are presented to confirm the theoretical results and illustrate the efficiency of the method. © 2012 Copyright Taylor and Francis Group, LLC.
Zhou Y.-L.,Foshan University |
Luo D.-M.,Foshan University
Journal of Alloys and Compounds | Year: 2011
Corrosion behavior of (α + β) Ti-10Mo and β Ti-20Mo (mass%) alloys cold rolled and solution heat treated was investigated by studying the anodic polarization curves at 310 K in 5 mol% HCl solution to determine the potential use of those alloys in biomedical applications. The anodic films formed on the surfaces of the alloys were examined using X-ray photoelectron spectroscopy analysis and scanning electron microscopy. The results reveal that both of the Ti-Mo alloys cold rolled and solution treated exhibit a passive behavior in 5% HCl solution, which is attributed to the passive film formation of a mixture of MoO3 and TiO2. The cold rolling process does not influence the formation of passive films on the Ti-Mo alloys although it slightly increases the passive current densities. The corrosion resistance of the Ti-Mo alloys increases with Mo content and both of the Ti-Mo alloys exhibit better corrosion resistance than commercial pure Ti - the currently used metallic biomaterial. © 2011 Elsevier B.V. All rights reserved.
Luo X.-P.,Foshan University
Cell Biochemistry and Function | Year: 2014
The pathogenesis of lung cancer is to be further investigated. Recent reports indicate that phospholipase C ε-1 (PLCE1) is a critical molecule involved in tumour growth. This study aims to investigate the role of PLCE1 in the regulation of apoptosis in lung cancer cells. In this study, the surgically removed non-small-cell lung cancer (NSCLC) tissue was collected from 36 patients. Single NSCLC cells were prepared from the tissue, in which immune cells of CD3+, CD11c+, CD19+, CD68+ and CD14+ were eliminated by magnetic cell sorting. The expression of PLCE1 and p53 was assessed by quantitative real-time polymerase chain reaction and Western blotting. Apoptosis of NSCLC cells was analysed by flow cytometry. The results showed that, in cultured NSCLC cells, high levels of PLCE1 and low levels p53 were detected; the two molecules showed a negative correlation (p<0.01). The addition of anti-PLCE1 antibody increased the expression of p53 in NSCLC cells, which increased the frequency of apoptotic NSCLC cells. We conclude that NSCLC cells express high levels of PLCE1, which suppresses the expression of p53 in NSCLC cells. PLCE1 can be a therapeutic target of NSCLC. © 2013 John Wiley & Sons, Ltd.
Zhou Y.-L.,Foshan University |
Luo D.-M.,Foshan University
Materials Characterization | Year: 2011
In this study, the microstructures and mechanical properties of Ti-10Mo and Ti-20Mo alloys (mass%) are investigated to assess the potential use in biomedical applications. The microstructures are examined by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). The mechanical properties are determined from uniaxial tensile tests. The experimental results indicate that the microstructures and mechanical properties of Ti-Mo alloys are dependent upon the cold rolling, solution heat treatment, and Mo content. The Ti-10Mo alloy exhibits (α″ + β) and (β + ω) phases under the cold rolling (CR) and solution treatment (ST), respectively. By contrast, the Ti-20Mo alloy comprises only β phase under such conditions. The quenched Ti-20Mo alloy has the lowest elastic modulus and CR Ti-20Mo alloy has the highest tensile strength. The quenched Ti-10Mo alloy exhibits the excellent ductility and two-stage yielding from stress-strain curves due to the stress-induced martensite transformation from β to α″ during tensile deformation. These Ti-Mo alloys exhibit low yield strength and good ductility, and they are more suitable for biomedical applications than the conventional metallic biomaterials from the viewpoint of better mechanical compatibility. The quenched Ti-10Mo alloy has some advantages over the other β binary Ti-Mo alloys for biomedical applications. β type Ti-Mo-Sn alloys are expected to be promising candidates for novel metallic biomaterials. © 2011 Elsevier Inc. All rights reserved.