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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 Science 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.

Research on Influence of Cutting Conditions on Roundness of Ultra-thin Wall Parts in Ultrasonic Vibration Cutting

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厦门大学学报（自然科学版） 2002年第S1期41卷 75-76页

作者： JIAO Feng 1, ZHAO Bo 1,2. LIU Chuan-shao 1, GAO Guo -fu 1 (1. department of Mechanical Engineering, Jiaozuo Institute of Techno logy, Henan 454000, china 2. Institute of Mechanical Engineering,{2., shanghai 2.0030, china)

In the paper, the experimental researches were carr ie d out to discuss the roundness forming rule and the influence of cutting paramet ers on roundness by ultrasonic vibration cutting of the camera’s guiding drawtu be with 47.75 mm diameter and 0.6～1.5 mm wall thickness. The research results s h ow that the roundness error of ultra-thin wall parts in ultrasonic vibration cu tting is only one third of that in common cutting. The relations between the rou ndness error and the cutting parameters behave as: (1) The roundness error in co mmon cutting decreases gradually with the rise of cutting speed, while in ultras onic cutting, the roundness changes not obviously till the cutting speed is up t o a value, which is nearly equal to one third of the critical velocity. Then the roundness of workpiece will begin to increase slowly. (2. The roundness error i ncreases along with the feed rate both in common cutting and ultrasonic cutting. (3) Within the range of cutting depth in experiment, the influence of cutting d epth on the roundness error is more obvious in common cutting than that in ultra sonic vibration cutting. The conclusions are useful in machining such precise ul tra-thin wall parts. According to the tests, the following conclusions can be o btained: 1) Compared with common cutting, ultrasonic cutting can decrease effect ively roundness error of the workpiece. Under the same condition, the roundness error of the ultra-thin wall part in ultrasonic turning is about one third of t hat in common cutting. 2. In common cutting, cutting depth and feed rate have mu ch influence on the roundness and the influence of cutting velocity is little. W hile in ultrasonic cutting, the roundness was influenced heavily only when feed rate is more than 0.1 mm/r and cutting speed is more than 1/3 of the critical ro tation speed, cutting depth has little influence on the roundness in the experim ent. 3) Kerosene-oil is an optimum cutting fluid in machining ultra-thin wall workpiece.

关键词： ultra-thin wall part ultrasonic vibration cutt ing roundness guiding drawtube

Optimal power allocation for cognitive relay networks: amplify-and-forward versus selection relay

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Science china(Information Sciences) 2011年第4期54卷 861-872页

作者： YUE WenJing 1,2.ZHENG BaoYu 1,2.MENG QingMin 1,YUE WenJie 3 & CUI JingWu 1 1 Institute of Signal Processing and Transmission,Nanjing university of Posts and Telecommunications,Nanjing 2.0003,china 2.{2. of Electronic Engineering,shanghai jiaotong university,shanghai 2.02.0,china 3 Shanxi Institute of Educational Science,Taiyuan 030009,china 1. Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China2. Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China3. Shanxi Institute of Educational Science Taiyuan 030009 China

We consider a cognitive relay network which is defined by a source,a destination,and cognitive relay nodes and primary user *** this network,a source is assisted by cognitive relay nodes which allow coexisting with primary user nodes by imposing severe constraints on the transmission power so that they operate below the noise floor of primary user *** this paper,we mainly study the power allocation strategies of this system to minimize the outage probability subject to total and individual power constraints for cognitive relay nodes and subject to interference constraints for primary user nodes.A relay transmission scheme,namely amplify-and-forward (AF),is *** first present an optimal power allocation (OPA) scheme to minimize the system outage probability,based on instantaneous channel state information among the source,destination and relay nodes and mean channel gains between primary user nodes and cognitive ***,we propose a selection AF scheme (S-AF) where the single best relay is chosen to assist in the transmission and study power allocation strategy for S-AF to minimize outage *** analytical power allocation strategies have been validated through numerical *** results indicate that the AF with OPA and S-AF with OPA have significantly better outage behavior and average throughput than AF and S-AF schemes *** also find that S-AF with OPA achieves a higher throughput,and hence lower outage probability than AF with OPA.

关键词： cognitive radio (CR) relay networks power allocation outage probability

Research on the Characters of the Cutting Force in Vibration Cutting Particle Reinforced Metal Matrix Composites SiC_p/Al

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厦门大学学报（自然科学版） 2002年第S1期41卷 74-75页

作者： LIU Chuan-shao 1, ZHAO Bo 1,2. GAO Guo-fu 1, JIAO F eng 1 (1. department of Mechanical Engineering, Jiaozuo Institute of Techno logy, Henan 454000, china 2. Institute of Mechanical Engineering,{2., shanghai 2.0030, china)

In this paper, turning experiments of machining particle reinforced metal matri x composites(PRMMCs) SiC p/Al with PCD tools have been carried out. The cutting force characteristics in ultrasonic vibration turning compared with that in com mon turning were studied. Through the single factor experiments and multiple fac tor orthogonal experiments, the influences of three kinds of cutting conditions such as cutting velocity, amount of feed and cutting depth on cutting force were analyzed in detail. Meanwhile, according to the experimental data, the empirica l formula of main cutting force in ultrasonic vibration turning was conclude d. According to the test results, the cutting force is direct proportion to cutt ing depth basically according to the relation between cutting force and other fa ctors, which is similar to that of common cutting, so is the feed rate, but the influence is not so big. The influence of cutting speed is larger than that of f eed rate on cutting force because the efficient cutting time increases in vibrat ion cycle with the increase of cutting speed, which causes cutting force to incr ease. The research results indicate: (1) Ultrasonic vibration turning possesses much lower main cutting force than that in common turning when adopting smaller cutting parameters. If using larger cutting parameters, the difference will inco nspicuous. (2. There are remarkable differences of cutting force-cutting veloci ty characteristics in ultrasonic vibration turning from that in common turning m ainly because built-up edge does not emerge in ultrasonic turning unlike common turning in corresponding velocity range. (3) In ultrasonic vibration cutting, t he influence of cutting velocity on cutting force is most obvious among thre e cutting parameters and the influence of feed is smallest. So adopting lower cu tting velocity and larger cutting depth not only can reduce cutting force effect ively but also can ensure cutting efficiency. (4) The conclusions are usefu

关键词： composite SiC p/Al PCD tool ultrasonic vibrati on turning cutting force

Generalized two-dimensional correlation spectroscopy——Theory and applications in analytical field

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Science china Chemistry 2004年第3期47卷 257-266页

作者： DOU Xiaoming1, YUAN Bo1, ZHAO Haiying1, YIN Guangzhong2.& Yukihiro Ozaki3 1. Molecular and Photonics Laboratory, Physical department, shanghai Jiao Tong {2., shanghai 2.0030, china 2. Suzhou No.2.People抯 Hospital, Suzhou 2.5000, china 3. Chemical department, School of Science and Technology, Kwansei-Gakuin {2., Sanda 669-1337, Japan Molecular and Photonics Lab. Phys. Dept. Shanghai Jiaotong Univ. Shanghai 200030 China Suzhou No. 2.People's Hospital Suzhou 215000 China Chem. Dept. Sch. of Sci. and Technol. Kwansei-Gakuin Univ. Sanda 669-1337 Japan

Since the theory of generalized two-dimensional (2.D) correlation spectroscopy was proposed, it has been keenly concerned in scientific research and its analytical method has been widely applied in various analytical fields. The mathematical process to construct generalized 2.D correlation spectroscopy and the physical meaning of 2.D correlation spectral map are described, and three examples in the fields of chemical analysis and molecular biology are provided, such as the component analysis of organic solvent, the analysis of biological molecules in the solvent with different pH values and structural analysis of protein. The theory and analytical method of generalized 2.D correlation spectroscopy are also detailedly commented.

关键词： generalized two-dimensional correlation spectroscopy, analytical method.

PHASE TRANSFORMATION UNIT OF BAINITIC FERRITE AND ITS SURFACE RELIEF IN LOW AND MEDIUM CARBON ALLOY STEELS

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Acta Metallurgica Sinica(English Letters) 1989年第3期2卷 161-167页

作者： YU Degang CHEN Dajun ZHENG Jinghong HE Yirong SHEN Fufa shanghai jiaotong university,shanghai,{2. Professor,department of Materials Science and Engineering,shanghai jiaotong university,1954 Huashan Road,shanghai 2.0030,{2.

The lath-or plate-shaped bainitic ferrite of low and medium carbon alloy steels consists of packets of ferrite sublaths which are composed of many finer and regular ferrite *** are uniform shear growth units of bainitic phase *** carbide is precipitated from *** bainitic O-carbides are precipitated from γ-α interface or carbon-rich *** mode of arrangement of the units in ferrite sublath packet is in uni-or bi-di- *** surface relief is produced by the accumulation of uniform shear strains with all the ferrite units arranged unidirectionally in a sublath packet,while tent-shaped surface relief is formed by the integration of the uniform shear strains of two groups with ferrite units piling up in two directions and growing face to face;whereas if they grow back to back,the integra- tion will be responsible for invert-tent-shaped surface *** interface trace between two groups of ferrite units in a sublath packet is shown as“midrib”.

关键词： low and medium carbon alloy steels bainite ferrite phase transformation unit surface relief

Constructing Product Ontologies with an Improved Conceptual Clustering Algorithm

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Journal of Systems Engineering and Electronics 2002年第3期13卷 71-77页

作者： Cao Dajun & Xu Liangxian department of Computer Science, shanghai jiaotong university,{2., P.R. china department of Computer Science Shanghai Jiaotong University Shanghai 200030 P. R. China

In a distributed eMarketplace, recommended product ontologies are required for trading between buyers and sellers. Conceptual clustering can be employed to build dynamic recommended product ontologies. Traditional methods of conceptual clustering (e.g. COBWEB or Cluster/2. do not take heterogeneous attributes of a concept into account. Moreover, the result of these methods is clusters other than recommended concepts. A center recommendation clustering algorithm is provided. According to the values of heterogeneous attributes, recommended product names can be selected at the clusters, which are produced by this algorithm. This algorithm can also create the hierarchical relations between product names. The definitions of product names given by all participants are collected in a distributed eMarketplace. Recommended product ontologies are built. These ontologies include relations and definitions of product names, which come from different participants in the distributed eMarketplace. Finally a case is given to illustrate this method. The result shows that this method is feasible.

关键词： Machine learning Conceptual clustering Product ontologies Electronic marketplace.

Automatic Software Install/Update for Embedded Linux

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Journal of shanghai jiaotong university(Science) 2008年第1期13卷 107-109页

作者：陶莉黄佩伟 department of Electronic Engineering Shanghai Jiaotong University

Linux has a special feature of automount in the Linux kernel. Filesystem can be mounted and unmounted automatically. Its performance is similar to MS Windows. It works well under demands of more saving resources and automatization, like memory of system. An approach to install/update software automatically on embedded platform was proposed. This approach derives from above feature based on embedded environment with Linux OS. Configurations of files related to this feature were introduced. An example in practice was given to realize this approach from universal serial bus (USB) memory disk when USB disk is available.

关键词： automount universal serial bus (USB) disk autofs automisc autorun.sh install.shf

A HIGH RESOLUTION FINITE VOLUME METHOD FOR SOLVING SHALLOW WATER EQUATIONS

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Journal of Hydrodynamics 2000年第1期12卷 35-41页

作者： Wang Jia song School of Civil Engineering and Mechanics, shanghai jiaotong university, shanghai 2.0030, P.R.{2.Ni Hang gen department of Civil and Structure Engineering, Dalian university of Technology, Dalian 11602., P.R.{2. shanghai jiaotong Univ Shanghai China

A high resolution finite volume numerical method for solving the shallow water equations is developed in this paper. In order to extend finite difference TVD scheme to finite volume method, a new geometry and topology of control bodies is defined by considering the corresponding relationships between nodes and elements. This solver is implemented on arbitrary quadrilateral meshes and their satellite elements, and based on a second order hybrid type of TVD scheme in space discretization and a two step Runge Kutta method in time discretization. Then it is used to deal with two typical dam break problems and very satisfactory results are obtained comparied with other numerical solutions. It can be considered as an efficient implement for the computation of shallow water problems, especially concerning those having discontinuities, subcritical and supercritical flows and complex geometries.

关键词： shallow water equations finite volume TVD scheme dam break bores