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A Group-Oriented (t,n) Threshold Signature Scheme with Traceable Signers

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Wuhan University Journal of Natural Sciences 2008年第6期13卷 680-684页

作者： TAN Zuowen1,2 1. School of information Technology, Jiangxi University of Finance and Economics, Nanchang 330013, Jiangxi, china 2. state key laboratory of information security/Institute of Software, Chinese Academy of Sciences, beij.ng 100190, china School of information Technology Jiangxi University of Finance and Economics Nanchang 330013 Jiangxi China state key laboratory of information security/Institute of Software Chinese Academy of Sciences Beijing 100190 China

A group-oriented （t, n） threshold signature scheme employs the cryptographic techniques of secret share, allows any subset of t players out of n players to sign message on behalf of the group and disallows the creation of a valid signature if fewer than t players take part in the signature protocol. In this paper, we proposed a new group-oriented （t, n） threshold signature schemes with traceable signers based on Schnorr signature. The proposed scheme is proved traceable, robust and unforgeable against the ＂static＂ adversary with the discrete logarithm assumption in the random oracle model and existence of broadcast channel. The proofs of the strongest security （existential unforgeability against adaptively chosen message attacks under the discrete logarithm assumption） are provided in the random oracle model.

关键词： threshold signature random oracle model robustness

Fair Non-Repudiation for Web Services Transactions

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Wuhan University Journal of Natural Sciences 2010年第5期15卷 385-392页

作者： SU Ruidan,FU Shaofeng,ZHOU Lihua key laboratory of Computer Network and information security of the Ministry of Education,Xidian University,Xi’an 710071,Shaanxi,china key laboratory of Computer Network and information security of the Ministry of Education Xidian University Xi’an Shaanxi China

To safeguard the interests of transacting parties,non-repudiation mechanisms need to assure fairness and *** non-repudiation service currently implemented usually does not consider the requirement of fairness and the fair non-repudiation protocols to date can not be suitably applied in real environment due to its complex *** paper discusses the transaction-oriented non-repudiation requirement for Web services transaction,analyzes the constraints of the traditional model for the available fair non-repudiation protocols and designs a new Online-TTP fair non-repudiation *** new protocol provides a fair non-repudiation solution to secure Web services transactions and can be embedded into a single Web service *** protocol adopts evidence chained to decreasing the overhead of evidence verification and management and alleviates the overhead of certificate revocation checking and time-stamp generation for *** protocol has strong fairness,timeliness,efficiency and practicability.

关键词： fair non-repudiation Web services transaction evidence chaining timeliness

A tetrahedral data model for unstructured data management

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Science china(information Sciences) 2010年第8期53卷 1497-1510页

作者： LI Wei & LAng Bo state key laboratory of Software Development Environment, Beihang University, beij.ng 100191, china 1. state key laboratory of Software Development Environment Beihang University Beijing 100191 China

This paper proposes a tetrahedral data model for unstructured data management. The model defines the four components of unstructured data including: basic attributes, semantic characteristics, low-level features and raw data on its four facets, and the relations between these components. The internal implementation structure of the model and the data query language are designed and briefly introduced. This model provides a unified, integrated and associated description for different kinds of unstructured data, and supports intelligent data services such as associated retrieval and data mining. An example is given to demonstrate how to use the model for describing and manipulating data from a sample video base.

关键词： unstructured data data model query language associated retrieval intelligent services

Secure multi-party computation protocol for sequencing problem

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Science china(information Sciences) 2011年第8期54卷 1654-1662页

作者： TAng ChunMing 1,2,SHI GuiHua 1 & YAO ZhengAn 3 1 School of Mathematics and information Science,Guangzhou University,Guangzhou 510006, china 2state key laboratory of information security, Institute of Software Science,Chinese Academy of Sciences,beij.ng 100080,china 3 School of Mathematics and Computational Science,Sun Yat-Sen University,Guangzhou 510275,china 1. School of Mathematics and information Science Guangzhou University Guangzhou 510006 China2. State Key Laboratory of Information Security Institute of Software Science Chinese Academy of Sciences Beijing 100080 China3. School of Mathematics and Computational Science Sun Yat-Sen University Guangzhou 510275 China

In the field of multi-party computation,an important problem is how to construct an efficient and secure multi-party computation protocol for certain specific *** the present study,we make use of a secret sharing scheme to construct an efficient and secure multi-party computation protocol for sequencing *** protocols are perfectly secure against both a passive adversary that can corrupt at most t (n-1)/2 participants, and an active adversary that can corrupt at most t ng problem is the Millionaires' problem.

关键词： secure multi-party computation sequencing problem secret sharing

Study on internal quantum efficiency of blue IngaN multiple-quantum-well with an IngaN underneath layer

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Science china(Technological Sciences) 2010年第2期53卷 306-308页

作者： WAng JiaXing, WAng Lai, ZHAO Wei, ZOU Xiang & LUO Yi National laboratory for information Science and Technology/state key laboratory on Integrated Optoelectronics, Department of Electronic Engineering, Tsinghua University, beij.ng 100084, china 1. National laboratory for information Science and Technology/state key laboratory on Integrated Optoelectronics Department of Electronic Engineering Tsinghua University Beijing 100084 China

Blue IngaN multiple-quantum-well (MQW) samples with different InxGa1-xN (x=0.01–0.04) underneath layers (ULs) were grown by metal organic vapor phase epitaxy (MOVPE). Temperature dependent photoluminescence showed that the IngaN UL can improve the internal quantum efficiency (IQE) of MQW effectively due to strain release. And a maximum IQE of 50% was obtained when the thickness and In content of the IngaN UL were 60 nm and 0.01, respectively. Furthermore, the larger In content or thickness of the IngaN UL makes the IQE lower. Arrhenius fit to the experiment data showed that the IQE fall was mainly caused by the quantity increase of the nonradiative recombination centers, which was believed related to the accumulated stress in IngaN ULs.

关键词： IngaN underneath layer (UL) multiple-quantum-well (MQW) internal quantum efficiency (IQE) Arrhenius formula

Accurate location of all surface wave modes for Green's functions of a layered medium by consecutive perturbations

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Science china(information Sciences) 2010年第11期53卷 2363-2376页

作者： SOng Zhe, ZHOU HouXing, HU Jun, LI WeiDong & HOng Wei state key laboratory of Millimeter Waves, School of information Science and Engineering, Southeast University, Nanjing 210096, china 1. state key laboratory of Millimeter Waves School of Information Science and Engineering Southeast University Nanjing 210096 China

In this paper, an efficient method is proposed to quickly and accurately locate all the surface wave modes of spectral Green’s functions of a layered medium. This method consists of two parts. In the first part, all the surface wave poles without considering the medium loss are located by a modified dichotomy on the real axis in the complex plane. In the second part, consecutive perturbations with respect to the medium loss are performed, which means that the medium loss is increased step by step from zero to the given value, and at each step, the Newton-Raphson algorithm is employed to find all the current poles, with the poles at the previous step as initial values. The residues of the surface wave poles are analytically calculated without any contour integral. The whole procedure is based on the recursively rational forms of spectral Green’s functions. As an application, all the surface wave poles and their residues obtained by the method proposed in this paper are applied in evaluation of the spatial Green’s functions by the discrete complex image method. Some numerical examples are provided to validate the correctness and efficiency of the proposed method.

关键词： Green’s function Sommerfeld integral surface wave pole perturbation discrete complex image method

Study on attribute characterization for reservoir dynamic monitoring by seismic

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Science china Earth Sciences 2008年第S2期51卷 218-225页

作者： CHEN XiaoHong1,3,LI JingYe2,3 & ZHAO Wei4 1 key Lab of Geophysical Exploration of CNPC,china Petroleum University,beij.ng 102249,china 2 Basin & Reservoir Research Center,china Petroleum University,beij.ng 102249,china 3 state key laboratory of Petroleum Resource and Prospecting,china University of Petroleum,beij.ng 102249,china 4 Research Center of CNOOC,beij.ng 100027,china 1. key Lab of Geophysical Exploration of CNPC China Petroleum University Beijing 102249 China 3. state key laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China 2. Basin & Reservoir Research Center China Petroleum University Beijing 102249 China 4. Research Center of CNOOC Beijing 100027 China

Study on characterizing reservoir parameters dynamic variations by time-lapse seismic attributes is the theoretical basis for effectively distinguishing reservoir parameters variations and conducting time-lapse seismic interpretation,and it is also a key step for time-lapse seismic application in real oil fields. Based on the rock physical model of unconsolidated sandstone,the different effects of oil saturation and effective pressure variations on seismic P-wave and S-wave velocities are calculated and analyzed. Using numerical simulation on decoupled wave equations,the responses of seismic amplitude with different offsets to reservoir oil saturation variations are analyzed,pre-stack time-lapse seismic attributes differences for oil saturation and effective pressure variations of P-P wave and P-S converted wave are calculated,and time-lapse seismic AVO (Amplitude Versus Offset) response rules of P-P wave and P-S converted wave to effective pressure and oil saturation variations are compared. The theoretical modeling study shows that it is feasible to distinguish different reservoir parameters dynamic variations by pre-stack time-lapse seismic information,including pre-stack time-lapse seismic attributes and AVO information,which has great potential in improving time-lapse seismic interpreta-tion precision. It also shows that the time-lapse seismic response mechanism study on objective oil fields is especially important in establishing effective time-lapse seismic data process and interpreta-tion scheme.

关键词： time-lapse seismic dynamic monitoring rock physical model pre-stack attribute Amplitude Versus Offset (AVO)

Design theory and method of multivariate hash function

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Science china(information Sciences) 2010年第10期53卷 1977-1987页

作者： WAng HouZhen 1,2 , ZHAng Huanguo 1 , WU QianHong 1 , ZHAng Yu 1 , LI ChunLei 1 & ZHAng XinYu 1 1 The key laboratory of Aerospace information security and Trusted Computing, Ministry of Education, School of Computer, Wuhan University, Wuhan 430072, china 2 key laboratory of Mathematics Mechanization, beij.ng 100080, china 1. The key laboratory of Aerospace information security and Trusted Computing Ministry of Education School of Computer Wuhan University Wuhan 430072 China2. Key Laboratory of Mathematics Mechanization Beijing 100080 China

This paper proposes a novel hash algorithm whose security is based on the multivariate nonlinear polynomial equations of NP-hard problem over a finite field and combines with HAIFA iterative framework. Over the current widely used hash algorithms, the new algorithm has the following advantages: its security is based on a recognized difficult mathematical problem; the hash length can be changed freely; its design can be automated such that users may construct specific hash function meeting the actual needs. Furthermore, we discuss the security, efficiency and performance of the new algorithm. Under some related difficult mathematical assumptions and theoretical analysis, the new algorithm is proven practical by the experiment results, and capable of achieving security of an ideal hash function by choosing suitable parameters. In addition, it can also be used as a pseudo-random number generator for the good randomness of its output.

关键词： cryptology hash function MQ problem multivariate polynomials

Simulation of dam breach development for emergency treatment of the Tangjiashan Quake Lake in china

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Science china(Technological Sciences) 2008年第S2期51卷 82-94页

作者： WAng GuangQian,LIU Fan,FU XuDong & LI TieJian state key laboratory of Hydroscience and Engineering,Tsinghua University,beij.ng 100084,china state key laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

The Tangjiashan Quake Lake is the largest quake lake triggered by the 5.12 Wenchuan Earthquake that happened on May 12,2008 in china,posing high risk of catastrophic flash flood hazards to downstream human life and properties.A physics-based numerical simulation approach is proposed for real-time prediction of dam breach development of the Tangjiashan Quake Lake in the case of emergency *** erosion and lateral development of the dam breach are represented through accounting for the underlying physics including selective sediment transport and gravitational *** breach erosion model that involves few parameters enables quick calibration based on the monitored hydrological data in emergency analysis where fully geotechnical information about the barrier dam is not *** process of dam breach development is found to be nonlinear in cascades due to the combined effects of headcutting and bank *** agreement between the simulation results and the observed data shows the applicability of the present approach for emergency analysis of quake *** will arise in the situation where the soil composition of barrier dam is significantly *** of circular arc failure for cohesive soil and lateral seepage in bank slope will also enhance its applicability to complex situations.

关键词： quake lake earthquake dam breach simulation numerical model erosion collapse headcutting