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Modeling and verifying Web services driven by requirements:An ontology-based approach

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science in china(Series F) 2006年第6期49卷 792-820页

作者： HOU Lishan1,3.JIN ZHi1,2.& WU Budan1,4 1. Academy of mathematics and systems {2., chinese Academy of sciences, Beijing 100080, china 2. Institute of Computing Technology, chinese Academy of sciences, Beijing 100080, china 3. Institute of Software, chinese Academy of sciences, Beijing 100080, china 4. Graduate University of chinese Academy of sciences, Beijing 100049, china Academy of mathematics and systems {2. Chinese Academy of Sciences Beijing China Institute of Software Chinese Academy of Sciences Beijing China Institute of Computing Technology Chinese Academy of Sciences Bejing China Graduate University of chinese Academy of sciences Beijing China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

Approximation of dense-n/2.subgraph and table compression problems

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science china {2. 2005年第9期48卷 1223-1233页

作者： XU Dachuan~1 HAN Jiye~2.& DU Dongle~3.1. College of Applied sciences,Beijing University of Technology,Beijing 10002.,{3. 2. Institute of Applied {2.,Academy of {2. and systems science,chinese Academy of sciences,Beijing 100080,{3. 3. Faculty of Administration,University of New Brunswick,P.O.Box 4400,Fredericton,NB E3. 5A3.Canada College of Applied sciences Beijing University of Technology Beijing 100022 China Institute of Applied mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Faculty of Administration University of New Brunswick P.O. Box 4400 Fredericton NB E3B 5A3 Canada

We develop improved approximation algorithms for two NP-hard problems: the dense-n/2.subgraph and table *** on SDP relaxation and advanced rounding techniques,we first propose 0. 5982.and 0. 5970-approximation algorithms respec- tively for the dense-n/2.subgraph problem (DSP) and the table compression problem (TCP). Then we improve these bounds to 0. 62.3.and 0. 6708 respectively for DSP and TCP by adding triangle inequalities to strengthen the SDP *** results for TCP beat the 0. 5 bound of a simple greedy algorithm on this problem,and hence answer an open question of Anderson in an affirmative way.

关键词： dense-n/2.subgraph problem(DSP) table compression problem(TCP) SDP approximation ratio

On conformal measures for infinitely renormalizable quadratic polynomials

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science china {2. 2005年第10期48卷 1411-1420页

作者： HUANG Zhiyong~1 JIANG Yunping~(2.3. & WANG Yuefei~3.1. School of Information,Renmin University of china,Beijing 100872.china 2. Department of {2.,Queens College,City University of New York,NY 113.7,USA Department of {2.,Graduate School,City University of New York,New York,NY 10016,USA 3. Academy of {2. and systems science,chinese Academy of sciences,Beijing 100080,china School of Information Renmin University of China Beijing China Department of mathematics Queens College City University of New York NY USA Department of mathematics Graduate School City University of New York New York USA Academy of mathematics and systems {2. Chinese Academy of Sciences Beijing China

We study a conformal measure for an infinitely renormalizable quadratic polynomial. We prove that the conformal measure is ergodic if the polynomial is unbranched and has complex bounds. The main technique we use in t... 详细信息

关键词： Julia set, conformal measure, three-dimensional puzzle, infinitely renormalizable quadratic polynomial.

A tentative study for the prediction of the CME related geomagnetic storm intensity and its transit time

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science china(Technological {2.) 2005年第6期48卷 648-668页

作者： ZHAO Xinhua1,2.& FENG Xueshang1,3.1. SIGMA Weather Group, Key Laboratory of Space Weather, Center for Space science and Applied Re-search, chinese Academy of {2., Beijing 100080, china 2. Graduate School of the chinese Academy of {2., Beijing 10003., china 3. School of Geophysics and Geoinformation systems, china University of Geo{2., Beijing 100083. china SIGMA Weather Group Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate School of the chinese Academy of sciences Beijing China School of Geophysics and Geoinformation systems China University of Geosciences Beijing China

Using 80 CME-ICME events during 1997.1―2.02.9, based on the eruptive source locations of CMEs and solar magnetic field observation at the photosphere, a current sheet magnetic coordinate (CMC) system is established in order to study the propagation of CME and its geoeffectiveness. In context of this coordinate system, the effect of the eruptive source location and the form of heliospheric current sheet (HCS) at the eruptive time of CME on the geomagnetic storm intensity caused by CME and the CME’s transit time at the Earth is investigated in detail. Our preliminary conclusions are: 1) The geomagnetic disturbances caused by CMEs tend to have the so-called “same side-opposite side effect”, i.e. CMEs erupt from the same side of the HCS as the earth would be more likely to arrive at the earth and the geomagnetic disturbances associated with them tend to be of larger magnitude, while CMEs erupting from the opposite side would arrive at the earth with less probability and the corresponding geomagnetic disturbance magnitudes would be relatively weaker. 2. The angular separation between the earth and the HCS affect the corresponding disturbance intensity. That is, when our earth is located near the HCS, adverse space weather events occur most probably. 3. The erupting location of the CME and its nearby form of HCS will also affect its arrival time at the earth. According to these conclusions, in this context of CMC coordinate we arrive at new prediction method for estimating the geomagnetic storm intensity (Dstmin) caused by CMEs and their transit times. The application of the empirical model for 80 CME-ICME events shows that the relative error of Dst is within 3.% for 59% events with Dstmin≤?50 nT, while the averaged absolute error of transit time is lower than 10 h for all events.

关键词： coronal mass ejections, current sheet magnetic coordinate system, geomagnetic storm intensity, transit time, prediction method.

Two possible mechanisms for vortex self-organization

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science china Earth {2. 2006年第2期49卷 202-211页

作者： LUO Zhexian2. ZHOU Xiuji1 & GAO Shouting3.1. chinese Academy of Meteorological sciences, Beijing 100081, {2. 2. Department of Space Information science, Nanjing University of Information science and Technology, Nanjing 2.0044, {2. 3. Institute of Atmospheric Physics, chinese Academy of sciences, Beijing 10002., {2. Department of Environmental science Nanjing University of Information Science and Technology Nanjing China chinese Academy of Meteorological sciences Beijing China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

Review on the study of entanglement in quantum computation speedup

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chinese science Bulletin 2007年第16期52卷 2161-2166页

作者： DING ShengChao1,3.& JIN Zhi1,2.1 Institute of Computing Technology,chinese Academy of sciences,Beijing {2.,china 2.Academy of mathematics and systems science,chinese Academy of sciences,Beijing {2.,china 3.Graduate University of chinese Academy of sciences,Beijing {2.,china Institute of Computing Technology Chinese Academy of Sciences Beijing China Graduate University of chinese Academy of sciences Beijing China Academy of mathematics and systems {2. Chinese Academy of Sciences Beijing China

The role the quantum entanglement plays in quantum computation speedup has been widely disputed. Some believe that quantum computation's speedup over classical computation is impossible if entan-glement is absent,while others claim that the presence of entanglement is not a necessary condition for some quantum algorithms. This paper discusses this problem systematically. Simulating quantum computation with classical resources is analyzed and entanglement in known algorithms is reviewed. It is concluded that the presence of entanglement is a necessary but not sufficient condition in the pure state or pseudo-pure state quantum computation speedup. The case with the mixed state remains open. Further work on quantum computation will benefit from the presented results.

关键词：量子论量子纠缠量子计算加速模拟

Viscosity solution to nonlinear H_∞ control

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chinese science Bulletin 1997年第11期42卷 890-894页

作者： HONG Yiguang, YUNG Siupang, MEI Shengwei and QIN Huashu1. Institute of systems science, {2. Academy of {3., Beijing 100080, china 2. Department of mathematics, Hong Kong University, Hong Kong, china Institute of systems science Chinese Academy of Scirnces Beijing China Department of mathematics How Kong University Hong Kong China

where the state variable x∈R^n,the output z∈R^k,the control variable u∈U R^m,and thedisturbance w∈W R^l.U and W are compact.F,Z are C^1 mappings defined in a neigh-

关键词： nonlinear H∞ control viscosity solution disturbance attenuation.

Weight hierarchies of linear codes satisfying the Near-Chain condition

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Progress in Natural science:Materials International 2005年第9期15卷 784-792页

作者： LIU Zihui1** and CHEN Wende2.1. School of Mathematical sciences, Peking University, Beijing 100871, china 2. Laboratory of {2. and Control and Key State Laboratory of Information Security, Institute of {2. science, Academy of mathematics and {2. science, chinese Academy of sciences, Beijing 100080, china) School of Mathematical sciences Peking University Beijing 100871 China Laboratory of systems and Control and Key State Laboratory of Information Security Institute of Systems Science Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100080 China

The weight hierarchies of a linear [n,k;q] code C satisfying the Near-Chain condition are studied, almost all the weight hierarchies of such code are determined.

关键词： weight hierarchy Near-Chain condition difference sequence linear code.

A new principle of synthetic cascade utilization of chemical energy and physical energy

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science china(Technological {2.) 2005年第2期48卷 163-179页

作者： JIN Hongguang1, HONG Hui1,2. WANG Baoqun1,2. HAN Wei1,2.& LIN Rumou1,2.1. Institute of Engineering Thermophysics, chinese Academy of sciences, Beijing {2., china 2. Graduate School of the chinese Academy of sciences, Beijing 10003., china Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China Graduate School of the chinese Academy of sciences Beijing China

We propose a new principle of the cascade utilization of both chemical energy and physical energy in energy systems with the integration of chemical processes and thermal cycles. Particularly, a general equation of energy levels of substance, Gibbs free energy of chemical reaction and physical energy is explicitly founded. On the basis of this equation, a chemical-looping combustion and an indirect combustion are investigated. Furthermore, a mechanism of energy release, with the combination of decreasing the energy level of Gibbs free energy and upgrading the energy level of low or middle- temperature thermal energy, is clarified. The promising results obtained here establish a theoretical basis for the further investigation of multi-function systems in which energy and the environment are compatible, and create a new approach to improve the performance of traditional thermal cycles.

关键词： chemical energy, cascade utilization, exergy, energy conversion.