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Object Tracking and Tracing:Hidden Semi-Markov Model Based Probabilistic Location Determination

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Journal of shanghai jiaotong university({2.) 2011年第4期16卷 466-473页

作者：吴捷王东盛焕烨 department of computer {2. and engineering Shanghai Jiaotong University

The enhancement of radio frequency identification(RFID) technology to track and trace objects has attracted a lot of attention from the healthcare and the supply chain ***,RFID systems do not always function reliably under complex and variable deployment *** many cases,RFID systems provide only probabilistic observations of object ***,an approach to predict,record and track real world object states based upon probabilistic RFID observations is *** Markov model(HMM) has been used in the field of probabilistic location *** the inherent duration probability density of a state in HMM is exponential,which may be inappropriate for modeling of object location ***,in this paper,we put forward a hidden semi-Markov model(HSMM) based approach for probabilistic location determination. We evaluated its performance comparing with that of the HMM-based *** results show that the HSMM-based approach provides a more accurate determination of real world object states based on observation data.

关键词： object tracking and tracing hidden semi-Markov model(HSMM) probabilistic location determination radio frequency identification(RFID)

THE ROBUST CONTROL SCHEME FOR FREE-FLOATING SPACE MANIPULATOR TO TRACK THE DESIRED TRAJECTORY IN JOINTSPACE

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Acta Mechanica Solida Sinica 2001年第2期14卷 183-188页

作者： Chen Li (department of Mechanical engineering, Fuzhou University, Fuzhou 350002.{2.) Liu Yanzhu (department of engineering Mechanics,shanghai jiaotong University, shanghai 2.0030,{2.) ***

The control of a free-floating space manipulator system isdiscussed. With the augmentation approach, the nonlinearparameterization problem of the dynamic equations of the spacemanipulator system is overcome. Based on the results, the robustcontrol scheme for free-floating space manipulator with uncer- tainpayload parameters to track the desired trajectory in jointspace isproposed, and the global convergence of the tracking is verified byusing the Lyapunov method.

关键词： free-floating space maniulator augmentation approach robust control

THRESHOLD PROXY RE-SIGNATURE

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Journal of Systems science & Complexity 2011年第4期24卷 816-824页

作者： Piyi YANG Zhenfu CAO Xiaolei DONG department of computer {2. and engineering Shanghai Jiaotong University Shanghai 200240 China.

The focus of this paper is to design an efficient and secure solution addressing the semi trusted issue in proxy re-signature schemes, i.e., the proxy knows the re-signature key from user A to user B, so he is able to translate any signatures made by user A to user B, which damages the essential requirement （＂non-repudiation＂ property） of proxy re-signature schemes. In this paper, the authors first define the security model for threshold proxy re-signature scheme, and then propose two threshold proxy re-signature schemes based on Ateniese-Hohenberger＇s and Shao-Cao-Wang-Liang＇s approach.

关键词： Proxy re-signature robust threshold unforgeable.

Delayed feedback control experiments on some flexible structures

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Acta Mechanica Sinica 2010年第6期26卷 951-965页

作者： Guo-Ping Cai·Long-Xiang Chen department of engineering Mechanics, State Key Laboratory of Ocean engineering, shanghai jiaotong University,2.02.0 shanghai,china department of engineering Mechanics State Key Laboratory of Ocean Engineering Shanghai Jiaotong University Shanghai China

In recent decades,studies on delayed system dynamics have attracted increasing attention and advances have been achieved in stability,nonlinearity,delay identification, delay elimination and ***,most of the existing work is on the theoretical basis and little is on the *** paper presents our experimental studies on delayed feedback control conducted in recent years with the focus on the discussion of a DSP-based delayed experiment *** phenomena in our delay experiments are discussed and a few topics of interest for further research are brought forward.

关键词： Flexible beam Flexible plate Flexible manipulator Delayed feedback control Experiment

Physical Simulation of Nonmetallic Particle Movement in Al Melt under Electromagnetic Field

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Journal of Materials science & Technology 2001年第4期17卷 463-465页

作者： Tianxiao LI, Zhenming XU,Baode SUN,Da SHU and Yaohe ZHOU School of Materials science and engineering, {2. jiaotong University, {2. 2.0030, china shanghai Jiao Tong Univ Sch Mat Sci & Engn Shanghai 200030 Peoples R China

Physical simulation is used to study the movement of nonmetallic particles in Al melt in electro- magnetic field. It is found that the terminal velocity of particles in different Reynolds number range has different functions. By confirming drag force coefficient of nonmetallic particles with Reynolds number in the range of 0.2.10 and 10-2. respectively, two functions of terminal ve- locity for spherical nonmetallic particles have been got accordingly, which provide a theoretical basis for separating nonmetallic inclusions from Al melt in electromagnetic field.

关键词： Al Physical Simulation of Nonmetallic Particle Movement in Al Melt under Electromagnetic Field Simulation

An analytical model for SMAC protocol in multi-hop wireless sensor networks

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science china(Information sciences) 2010年第11期53卷 2323-2331页

作者： LUO Jun, JIANG LingGe& HE Chen department of Electronic engineering, {2. jiaotong University, shanghai 2.02.0, china 1. department of Electronic engineering Shanghai Jiaotong University Shanghai 200240 China

Considering the active/sleep dynamics and the contention backoscheme of SMAC protocol in multi-hop wireless sensor networks (WSNs), we model each node as a finite single server queue with server shutdown, and model each node’s states as a two-dimensional continuous-time Markov chain. Based on the model, we derive the network performance in terms of average packet loss ratio, network throughput, average packet delay and average power consumption. Experiment comparisons show that the analytical results match well with the simulation results, which validates the accuracy of the analytical model. Furthermore, using the analytical model can enable us to investigate the performance tradeobetween energy efficiency and QoS requirement, and give us theoretical insight into the optimal parameters such as duty cycle, mean active period and buffer size in multi-hop wireless sensor networks.

关键词： multi-hop wireless sensor networks Markov chain energy efficiency QoS

SURFACE MESH PARAMETERIZATION WITH NATURAL BOUNDARY

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Chinese Journal of Mechanical engineering 2003年第3期16卷 264-267页

作者： Ye MingZhu XiaofengWang ChengtaoSchool of Mechanical engineering,shanghai {2. University,shanghai 2.0030, china School of Mechanical engineering Shanghai Jiaotong University 上海 200030

Using the projected curve of surface mesh boundary as parameter domainborder, linear mapping parameterization with natural boundary is realized. A fast algorithm forleast squares fitting plane of vertices in the mesh boundary is proposed. After the mesh boundary isprojected onto the fitting plane, low-pass filtering is adopted to eliminate crossovers, sharpcorners and cavities in the projected curve and convert it into an eligible convex parameter domainboundary. In order to facilitate quantitative evaluations of parameterization schemes, threedistortion-measuring formulae are presented.

关键词： Parameterization Convex combination mapping Harmonic mapping Dirichletenergy

An Efficient Threshold Key-Insulated Signature Scheme

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Journal of shanghai jiaotong university({2.) 2011年第6期16卷 658-662页

作者：陈剑洪龙宇陈克非王永涛李祥学 department of computer {2. and engineering Shanghai Jiaotong University School of computer engineering Huaiyin Institute of Technology shanghai Key Laboratory of Scalable Computing and System Shanghai Jiaotong University department of computer {2. and Technology East China Normal University

To tackle the key-exposure problem in signature settings,this paper introduces a new cryptographic primitive named threshold key-insulated signature(TKIS) and proposes a concrete TKIS *** a TKIS system,at least k out of n helpers are needed to update a user's temporary private *** the one hand,even if up to k 1 helpers are compromised in addition to the exposure of any of temporary private keys,security of the non-exposed periods is still *** the other hand,even if all the n helpers are compromised,we can still ensure the security of all periods as long as none of temporary private keys is *** with traditional key-insulated signature(KIS) schemes,the proposed TKIS scheme not only greatly enhances the security of the system,but also provides flexibility and efficiency.

关键词： threshold key-insulation signature random oracle model

Rietveld Quantitative Analysis of Carbides Precipitation in Normalized-tempered 2.2.Cr-1Mo-0.2.V Steel

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Journal of Wuhan University of Technology(Materials science) 2009年第6期24卷 922-926页

作者：张永涛张汉谦 School of Materials science and engineering Shanghai Jiaotong University Research Institute Baoshan Iron & Steel Co.Ltd.

The quantitative determination of the mass fractions of precipitates in steels is very difficult using traditional materials characterization techniques. The Rietveld full-pattern fitting algorithm was introduced to solve this problem. The precipitated multicomponents’ mass fraction of M3C, MC, M7C3 and M2.C6 were evaluated precisely and relatively quickly. It is found evolution of carbides apparently occurs during tempering at high temperatures, and a two-step transformation mechanism is proposed for M7C3 during early tempering treatment. The method is an effective way on the investigation of precipitation kinetics, which may play a promising role in propertities’ enhancement and design of the heat-resistant steels.

关键词： 2.2.Cr-1Mo-0.2.V steel rietveld quantitative analysis precipitates