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A property-based attestation protocol for TCM

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Science china(Information Sciences) 2010年第3期53卷 454-464页

作者： FENG DengGuo1,2 & QIN Yu1,2 1State key laboratory of Information Security, Institute of Software, Chinese Academy of Science, Beijing 100190, china 2national Engineering Research Center of Information Security, Beijing 100190, china State key laboratory of Information Security Institute of Software Chinese Academy of Science Beijing China national Engineering Research Center of Information Security Beijing China

This paper presents a property attestation protocol for the security chip TCM (trusted cryptographic module) via analyzing the problems of the current property attestation, which is built on the property attestation model with the online trust third party. In the protocol the prover utilizes the zero-knowledge proof by the attribute certificates, configuration commitment and TCM signature, and attests its configuration and status which are compliant with the declarative security property. The protocol is characterized by shorter signature length and lower computations. The security of the protocol is proved at the random oracle model. The protocol can help extend application and improve standard for security chip TCM, and it also has practical value and immediate significance.

关键词： trust computing trust cryptographic module (TCM) property attestation signature of knowl- edge configuration commitment

Evolutionary patterns of Productida (Brachiopoda) morphology during the Permian in South china

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Science china Earth Sciences 2008年第11期51卷 1589-1600页

作者： ZHANG Yang1 & HE WeiHong1,2 1 Faculty of Earth Sciences, china University of Geosciences, Wuhan 430074, china 2 key laboratory of Biogeology and Environmental Geology of Ministry of Education, china University of Geosciences, Wuhan 430074, china Faculty of Earth Sciences China University of Geosciences Wuhan China key laboratory of Biogeology and Environmental Geology of Ministry of Education China University of Geosciences Wuhan China

The evolutionary patterns of Productida (brachiopod) morphology throughout the Permian show that while the percentage proportion of Productida (brachiopod) with strongly concentric and radial ornamentation declined from the Cisuralian to the Guadalupian, and then increased towards the Changhsingian via Wuchiapingian, the percentage proportion of Productida (brachiopod) with fine concentric and radial ornamentation distinctly increased from the Cisuralian to the Guadalupian, slightly declined towards the Wuchiapingian, and then increased towards the Changhsingian. From the Cisuralian to the Changhsingian, the percentage proportion of brachiopods with spinose ornamentation shows a persistent declining trend. The shell size generally indicates a miniaturization trend at species level during the Wuchiapingian to Changhsingian (including the transitional bed). These evolutionary patterns of brachiopod ornamentation and size are possibly related to the anoxia, food shortage, sea-level fluctuation, and change of substrate in the Permian (including the Permian-Triassic transitional interval) in South china.

关键词： brachiopod ornamentation size Permian South china

Aerodynamic/Stealthy/Structural Multidisciplinary Design Optimization of Unmanned Combat Air Vehicle

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Chinese Journal of Aeronautics 2009年第4期22卷 380-386页

作者： Hu Tianyuan,Yu Xiongqing key laboratory of Fundamental Science for national Defense-Advanced Design Technology of Flight Vehicle,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,china key laboratory of Fundamental Science for national Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

An optimization strategy is proposed to deal with the aerodynamic/stealthy/structural multidisciplinary design optimization （MDO） issue of unmanned combat air vehicle （UCAV）. In applying the strategy, the MDO process is divided into two levels, i.e. system level optimization and subsystem level optimization. The system level optimization is to achieve optimized system objective （or multi-objective） through the adjustment of global external configuration design variables. The subsystem level optimization consists of the aerodynamic/stealthy integrated design and the structural optimization. The aerodynamic/stealthy integrated design aims at achieving the minimum aerodynamic drag coefficient under the constraint of stealthy requirement through the adjustment of local external configuration design variables. The structural optimization is to minimize the structural weight by adjusting the dimefisions of structural components. A flowchart to implement this strategy is presented. The MDO for a flying-wing configuration of UCAV is employed to illustrate the detailed process of the optimization. The results indicate that the overall process of the surrogate-based two-level optimization strategy can be implemented automatically, and quite reasonable results are obtained.

关键词： aircraft design multidisciplinary design optimization aerodynamics radar cross section structure

Markov chain approach to identifying Wiener systems

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Science china(Information Sciences) 2012年第5期55卷 1201-1217页

作者： ZHAO WenXiao 1,2 & CHEN HanFu 1,2 1 key laboratory of Systems and Control,Institute of Systems Science,AMSS,Chinese Academy of Sciences,Beijing 100190,china 2 national Center for Mathematics and Interdisciplinary Sciences,Chinese Academy of Sciences,Beijing 100190,china key laboratory of Systems and Control Institute of Systems Science AMSS Chinese Academy of Sciences Beijing China national Center for Mathematics and Interdisciplinary Sciences Chinese Academy of Sciences Beijing China

Identification of the Wiener system composed of an infinite impulse response (IIR) linear subsystem followed by a static nonlinearity is *** recursive estimates for unknown coefficients of the linear subsystem and for the values of the nonlinear function at any fixed points are given by the stochastic approx-imation algorithms with expanding truncations (SAAWET).With the help of properties of the Markov chain connected with the linear subsystem,all estimates derived in the paper are proved to be strongly *** comparison with the existing results on the topic,the method presented in the paper simplifies the convergence analysis and requires weaker conditions.A numerical example is given,and the simulation results are consistent with the theoretical analysis.

关键词： Wiener system recursive identification stochastic approximation Markov chain strong consis-tency

The reflection of regular and irregular waves by a partially perforated caisson breakwater on a step bed

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Acta Oceanologica Sinica 2009年第4期28卷 107-117页

作者： LIU Yong LIYucheng TENG Bin XIA Zhisheng key laboratory of Ocean Engineering Ocean University of china Qingdao 266100 China State key laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China key laboratory of Water ＆ Water ＆ Sediment Science and Water Hazard Prevention Changsha 410076 China

This study examines the reflection of regular and irregular waves from a partially perforated caisson breakwater located on a step bed. The step bed is treated as an idealized rubble mound foundation. Based on the linear potential theory, an analytical solution is developed to calculate the reflection coefficient of the structure subjected to regular waves. The matched eigenfunction expansion method is used for the solution. The regular wave method is also extended to irregular waves using a linear transfer function. The calculated results obtained for limiting cases are exactly the same as corresponding results given by the previous researchers. The present predictions also agree well with experimental data in the published literatures. Numerical experiments are conducted to examine the variations of the reflection coefficient versus its main effect factors, and some interesting results are presented.

关键词： partially perforated caisson step irregular waves reflection coefficient

An efficient method for detecting concurrency errors in object-oriented programs

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Science china(Information Sciences) 2012年第12期55卷 2774-2784页

作者： HE YanXiang 1,2,WU Wei 2 & CHEN Yong 2 1 School of Computers,Wuhan University,Wuhan 430072,china 2 State key laboratory of Software Engineering,Wuhan University,Wuhan 430072,china School of Computers Wuhan University Wuhan China State key laboratory of Software Engineering Wuhan University Wuhan China

Multicore and multi-threaded processors have become the norm for modern ***,concurrent programs have become more and more prevalent despite being difficult to write and *** errors are highly likely to appear in concurrent code,conventional error detection methods such as model checking,theorem proving,and code analysis do not scale smoothly to concurrent *** is an indispensable technique for detecting concurrency errors,but it involves a great deal of manual work and is *** paper presents an automatic method for detecting concurrency errors in classes in object-oriented *** method uses a heuristic algorithm to automatically generate test cases that can effectively trigger ***,each test case is executed automatically and a fast method is adopted to identify the actual concurrency error from anomalous run *** have implemented a prototype of the method and applied it to some typical Java *** shows that our method is more effective and faster than previous work.

关键词： concurrency error dynamic test data race atomicity violations test case generation

SQUARE attack on block ciphers with low algebraic degree

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Science china(Information Sciences) 2010年第10期53卷 1988-1995页

作者： SUN Bing 1 , LI RuiLin 1 , QU LongJiang 1,3 & LI Chao 1,2,3 1 Science College of national University of Defense Technology, Changsha 410073, china 2 State key laboratory of Information Security, Graduate University of Chinese Academy of Sciences, Beijing 100049, china 3 national Mobile Communications Research laboratory, Southeast University, Nanjing 210096, china Science College of national University of Defense Technology Changsha China national Mobile Communications Research laboratory Southeast University Nanjing China State key laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China

By using an algebraic method, the mathematical foundation of SQUARE attack is studied in this paper. We point out that a SQUARE distinguisher exists if and only if the degree of the polynomial function between n-bit input which is active and n-bit output which is balanced is 2 n-2. And the algebraic method can also be used to determine the property of a balanced set after passed through a nonlinear S-box, by which in some cases we can find a SQUARE distinguisher with more rounds. The validity of SQUARE attack and the influence of the choice of S-box are also studied. If the round function of a Feistel cipher has a low algebraic degree, a SQUARE attack cannot recover the right keys in some special cases. However, SQUARE attack on SPN ciphers always holds. The relations among SQUARE attack and some other cryptanalytic method are studied, showing that if a cipher is breakable by SQUARE attack, then it is also breakable by the interpolation attack.

关键词： SQUARE attack interpolation attack integral attack block cipher

A study on volunteer augmentation navigation technology

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Science china(Physics,Mechanics & Astronomy) 2011年第6期54卷 1029-1034页

作者： WU HaiTao 1,2,LU XiaoChun 1,2,ZOU DeCai 1,2 & HAN Tao 1,2 1 national Time Service Center,Chinese Academy of Sciences,Xi’an 710600,china 2 key laboratory of Precision Navigation and Timing Technology,Chinese Academy of Sciences,Xi’an 710600,china national Time Service Center Chinese Academy of Sciences Xi’an China key laboratory of Precision Navigation and Timing Technology Chinese Academy of Sciences Xi’an China

Navigation augmentation technology is one of the most common methods to increase the continuity,reliability and integrity of the global satellite navigation *** concept of volunteer augmentation navigation (VNA) is proposed and the elements and topological structure of VNA are also analyzed in this *** study focuses on the neural network model that volunteers and ordinary users use modern communication information network to exchange self-organizing *** neural cell model of Volunteer Augmentation Navigation using shared information is *** interactive general relative positioning is *** basic theories and methods of volunteer augmentation navigation are formed on the basis of the above-mentioned *** study of realization mechanism of volunteer augmentation technology helps to form a relatively integral architecture of volunteer augmentation navigation.A user self-service satellite navigation augmentation which combines information exchange and navigation services may strengthen the continuity,reliability and integrity of the navigation *** volunteer augmentation navigation theory proposed in this paper improves the traditional satellite navigation application model and expands the connotation and denotation of satellite navigation augmentation methods.

关键词： volunteer augmentation navigation self-organizing information exchange interactive general relative positioning

On the placement of actuators and sensors for flexible structures with closely spaced modes

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Science china(Technological Sciences) 2010年第7期53卷 1973-1982页

作者： LIU XiaoXiang1,2 & HU Jun1,2 1 Beijing Institute of Control Engineering, Beijing 100190, china 2 State key laboratory of Science and Technology on Space Intelligent Control, Beijing 100190, china Beijing Institute of Control Engineering Beijing China State key laboratory of Science and Technology on Space Intelligent Control Beijing China

This paper analyzed the fundamental limitations of previous work and developed a new method to optimally locate actuators and sensors for structures with close modes. Optimization criteria were defined based on the distinguishing modal controllability and observability measures of close modes. An appropriate genetic algorism was adopted as the optimization algorism. Solving the high order Lyapunov functions was avoided by means of the closed-form expressions for controllability and observability Grammians. Since structure with widely separated natural frequencies is approximately balanced, computational efficiency was improved by grouping close modes together and dealing with the resulting subsystems independently. Finally, the effectiveness and optimality of the novel placement scheme were verified on a model structure with close modes.

关键词： close modes controllability/observability sensor/actuator optimization criterion optimization algorithm