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Shanghai, China

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.

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.

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.

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.

Liu Y.,Zhejiang Normal University | Zhao S.,Shanghai University of Engineering Science
Nonlinear Analysis: Real World Applications | Year: 2012

In this paper, the issue of controllability for linear time-varying systems with multiple time delays in the control and impulsive effects is addressed. The solution of such systems based on the variation of parameters is derived. Several sufficient and necessary algebraic conditions for two kinds of controllability, i.e., controllability to the origin and controllability, are derived. The relation among these conditions are established. A numerical example is provided to illustrate the effectiveness of the proposed methods. © 2011 Elsevier Ltd. All rights reserved.

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.

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