Shanghai University School of Computer Engineering and Science is considered a leading school in computer science and engineering fields in Shanghai, China, the school was one of earliest established in Shanghai. Professor Sanli Li, Dean of the school, is one of China’s pioneers in computer science and engineering.The school undertakes around 150 projects every year with support from the Natural Science Foundation of China, the Committee of Science and Technology of Shanghai Municipal Government, the Shanghai Municipal Education Committee, as well as from many other private firms or companies. The school has also received nine national and ministerial awards for scientific and engineering advancement.Departments:Department of Computer Application TechnologyDepartment of Computer Software and TheoryDepartment of Computer Architecture and OrganizationResearch Institutes:High Performance Computing and Application LaboratoryFault Tolerant Technology and Application LaboratoryIntelligent Information Processing LaboratoryMulti-media and Network LaboratoryCenter for Advanced Computing and Applications Laboratory Wikipedia.
Liu Y.,Zhejiang Normal University |
Zhao S.,Shanghai University of Engineering Science
IEEE Transactions on Automatic Control | Year: 2011
In this note, the controllability for a class of linear time varying impulsive systems with time delay in control input is studied. Sufficient and necessary conditions for the controllability of such systems are established. Specializing the obtained results to the cases of linear time-varying impulsive systems and linear time invariant impulsive systems with time delay, some simple criteria with respect to coefficient matrices, which are less conservative than some existing results are derived. It is also shown that the time delay in control input contributes to achieve the controllability of impulsive system even if the system is not controllable. Two examples are worked out to illustrate our results. © 2006 IEEE.
Yang Q.,Shanghai University of Engineering Science
Bulletin of Materials Science | Year: 2011
Crystalline γ-Al 2O 3 nanowires with diameter, 20.40 nm, length above 600 nm and aspect ratio above 30 have been successfully synthesized by thermal decomposition of boehmite (γ-AlOOH) precursors obtained via hydrothermal route by using AlCl 3, NaOH and NH 3 as starting materials. Thermogravimetric analysis (TG), differential thermal analysis (DTA), X-ray diffraction (XRD), transmission electron microscope (TEM), selected area electron diffraction (SAED) and high resolution transmission electron microscope (HRTEM) were used to characterize the features of the as-made γ -Al 2O 3 nanowires and their γ-AlOOH precursors. The pH value of the solution and the mixed precipitant play important roles in the formation of γ-AlOOH nanowires. After calcination at 500.C for 2 h, the orthorhombic γ-AlOOH transforms to cubic γ-Al 2O 3 and retains nanowire morphology. © Indian Academy of Sciences.
Wu J.,Shanghai University of Engineering Science
Advanced Materials Research | Year: 2010
In order to design the flow field of the NC-Electrochemical Machining (NC-ECM), a three-dimensional physical model of the flow passage is constructed based on the characteristic of the fluid flow, and three-dimensional flow field simulation is conducted with the applications of the Reynolds time-averaged Navier-Stokes equations and standard k-e turbulence numerical model, velocity vectors on workpiece surface are calculated respectively based upon the three cathode outlet slots under the steady electrochemical machining condition. The present analysis show that electrolyte insufficiency appeared on workpiece surface for initial cathode flow field, and the experiment results verified the correctness of numerical simulation. © (2010) Trans Tech Publications.
Xing Y.,Shanghai University of Engineering Science
Kybernetes | Year: 2013
Purpose: The key control characteristics (KCCs) are very important to control dimensional quality of the final product. The purpose of this paper is to propose optimization algorithm and rules of design KCCs by optimizing KCCs of 2D and 3D workpieces based on equations and candidate locating points. Design/methodology/approach: This paper analyzes optimization process of 2D and 3D rectangle workpieces based on equations and candidate locating points by using fruit fly optimization algorithm (FOA). For decreasing variables of the algorithm, the improved fruit fly optimization algorithm (IFOA) is presented. Moreover, the Euclidean norm of inverse Jacobian is used as the objective function of optimizing KCCs by comparing different objective functions. Finally, a case of side frame assembly is presented to illustrate design and optimization of KCCs through IFOA, and results show that the method proposed in this paper is efficient and precise. Findings: The paper provides some reasonable conclusions for the design and optimization of KCCs. Originality/value: This paper designs and optimizes KCCs of fixtures and parts to improve dimensional quality of the final product. © Emerald Group Publishing Limited.
Zhang L.,Shanghai University of Engineering Science
International Journal of Advanced Manufacturing Technology | Year: 2011
In free-form surface machining, the prediction of five-axis ball-end milling forces is quite a challenge due to difficulties of determining the underformed chip thickness and engaged cutting edge. Part and tool deflections under high cutting forces may result in poor part quality. To solve these concerns, this paper presents process modeling and optimization method for five-axis milling based on tool motion analysis. The method selected for geometric stock modeling is the dexel approach, and the extracted cutter workpiece engagements are used as input to a force prediction. The cutter entry-exit angles and depth of cuts are found and used to calculate the instantaneous cutting forces. The process is optimized by varying the feed as the tool-workpiece engagements vary along the toolpath, and the unified model provides a powerful tool for analyzing five-axis milling. The new feedrate profiles are shown to considerably reduce the machining time while avoiding process faults. © 2011 Springer-Verlag London Limited.
Zhao X.,Shanghai University of Engineering Science
Procedia Engineering | Year: 2011
According to Mallat multi-resolution analysis, A new edge detection algorithm based on multiscale product is presented, which uses Gaussian function and its first-derivative as lowpass and highpass filter to enhance edge and suppress noise, then detect edge embedded noise by gradient direction and updating search method. The experiments show that this approach has advantages of detecting edge in different gray contrast, high signal-noise ratio and pixel-level location accuracy. © 2011 Published by Elsevier Ltd.
Li J.,Shanghai University of Engineering Science
Advanced Materials Research | Year: 2012
MMT had been used widely as an antiknock additive in petrol. It can enhancing the vehicles dynamic performance and reduces fuel consumption, but causes some negative impact on vehicle emissions. In this paper, the author research on the emission performance of a vehicle which meet Stage IV emission standard use gasoline containing MMT run for 50,000km.The test results show emission pollution such as CO, HC and NOx increased by MMT which result in three-way catalytic converter deterioration quickly. MMT also made the oxygen sensor deterioration and cause high NOx emission. © (2012) Trans Tech Publications, Switzerland.
Xin S.S.,Shanghai University of Engineering Science |
Li M.C.,Shanghai University of Engineering Science
Corrosion Science | Year: 2014
The corrosion behaviour of 316L stainless steel was studied in the concentrated artificial seawater at 72. °C, i.e., the simulated low temperature-multi effect distillation environments, by using electrochemical measurement techniques. The corrosion state changes from spontaneous passivation to pitting after about 1150. h of immersion. Pitting corrosion is under mixed control of charge transfer and diffusion processes in the long-term immersion. The salt deposits retard the diffusion of oxygen to the metal surface. The pit depth only reaches about 38. μm after one year of immersion due to the alloying effect of Mo, low dissolved oxygen levels and weak occlusion states. © 2013 Elsevier Ltd.
Zhu J.,Shanghai University of Engineering Science
ICCASM 2010 - 2010 International Conference on Computer Application and System Modeling, Proceedings | Year: 2010
In the open environment of the Internet, E-commerce developes fast. How to transfer data securely and efficient is the key to the development of E-commerce. This paper analyses the security technology and proposes the security model based on PKI and digital signature.
Xu P.Q.,Shanghai University of Engineering Science
Materials and Design | Year: 2011
Dissimilar welding between cemented carbide and invar alloy was carried out using CO2 laser beam and argon arc as heat sources η Phase was formed near WC-Co/weld interface and precipitations in the fracture were discovered. In order to disclose the microstructure and mechanical property, firstly, η phase's morphology and composition at interface were investigated using backscattered electron imaging (BEI); and element diffusion across heat affected zone near WC-Co/weld interface was further studied. Secondly, bend strength values of butt joint with different welding parameters were tested by four-point bend strength experiment. Finally, WC migration mechanism was further discussed and the bend strength was measured. The results showed: (1) microstructures consisted of columnar crystals, cellular crystals, eutectic structure and fir-tree crystal and dendritic crystals. The columnar crystals were surrounded by lots of fir-tree crystals. (2) WC migration was driven by stirring effects of welds, high pressure of molten materials and ionized shielding gas, interface reaction and surface tension. (3) η Phases dispersion did not decrease bend strength of butt joint. And the maximum bend strength was 1493.56MPa, which was attributed to NbC precipitations featured with super-fine fir-tree. © 2010 Elsevier Ltd.