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Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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science china Earth sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2. WANG Qingfei1,2., HUANG Dinghua3 , WAN Li4. YANG Liqiang1,2.& GAO Bangfei1,2.1. State Key Laboratory of Geological Processes and Mineral Resources, china University of Geo{2.s, Beijing 100083, china 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, china University of Geo- {2.s, Beijing 100083, china 3. Faculty of Earth {2.s, china University of Geo{2.s, Wuhan 4.0074. china 4. school of mathematics and information science, guangzhou University, guangzhou 5104.5, china 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 China 3. Faculty of Earth sciences China University of Geosciences Wuhan 430074 China 4. school of mathematics and information science Guangzhou University Guangzhou 510405 China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

Secure multi-party computation protocol for sequencing problem

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science china({2. 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 {2. science,{4. University,{4. 510006, china 2.tate Key Laboratory of {2. Security, Institute of Software science,Chinese Academy of sciences,Beijing 100080,china 3 school of mathematics and Computational science,Sun Yat-Sen University,{4. 5102.5,china 1. school of mathematics and {2. 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 < n/3 *** simplest sequencing problem is the Millionaires' problem.

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

On the diophantine equation X^2.(1+a^2.Y^4.=-2.

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science china {2. 2010年第8期53卷 2143-2158页

作者： YUAN PingZhi 1 & ZHANG ZhongFeng 2.1 school of mathematics,South{2. Normal University,guangzhou 510631,{4. 2.school of mathematics & Computational science,Sun Yat-Sen University,guangzhou 5102.5,{4. 1. school of mathematics South China Normal University Guangzhou 510631 China2. School of Mathematics & Computational Science Sun Yat-Sen University Guangzhou 510275 China

Let a≥1 be an *** this paper,we will prove the equation in the title has at most three positive integer solutions.

关键词： algebraic approximations continued fractions elliptic curves quartic equations

Steganalysis of stochastic modulation steganography

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science in china(Series F) 2006年第3期49卷 273-285页

作者： HE Junhui1,2.& HUANG Jiwu1,2.1. school of information {2. and Technology, Sun Yat-sen University, guangzhou 5102.5,{4. 2. Guangdong Province Key Laboratory of information Security, guangzhou 5102.5,{4. 1. school of information {2. and Technology Sun Yat-sen University Guangzhou 510275 China 2. Guangdong Province Key Laboratory of information Security Guangzhou 510275 China

Stochastic modulation steganography embeds secret message within the cover image by adding stego-noise with a specific probabilistic distribution. No method is known to be applicable to the estimation of stochastic modulation steganography. By analyzing the distributions of the horizontal pixel difference of images before and after stochastic modulation embedding, we present a new steganalytic approach to accurately estimate the length of secret message in stochastic modulation steganography. The pro- posed method first establishes a model describing the statistical relationship among the differences of the cover image, stego-image and stego-noise. In the case of stegoimage-only steganalysis, rough estimate of the distributional parameters of the cover image＇s pixel difference is obtained with the use of the provided stego-image. And grid search and Chi-square goodness of fit test are exploited to estimate the length of the secret message embedded with stochastic modulation steganography. The experimental results demonstrate that our new approach is effective for steganalyzing stochastic modulation steganography and accurately estimating the length of the secret message.

关键词： information hiding steganography steganalysis stochastic modulation statistical distribution models of difference.

Twisted Ate pairing on hyperelliptic curves and applications

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science china({2. sciences) 2010年第8期53卷 1528-1538页

作者： ZHANG FangGuo 1,2.1 school of information {2. and Technology, Sun Yat-Sen University, guangzhou 5102.5,{4. 2.Guangdong Key Laboratory of information Security Technology, guangzhou 5102.5,{4. 1. school of information {2. and Technology Sun Yat-Sen University Guangzhou 510275 China2. Guangdong Key Laboratory of Information Security Technology Guangzhou 510275 China

In this paper we show that the twisted Ate pairing on elliptic curves can be generalized to hyperelliptic curves, and give a series of variations of the hyperelliptic Ate and twisted Ate pairings. Using the hyperelliptic Ate pairing and twisted Ate pairing, we propose a new approach to speeding up the Weil pairing computation. For some hyperelliptic curves with high degree twist, computing Weil pairing by our approach may be faster than Tate pairing, Ate pairing, and all other known pairings.

关键词： Ate pairing Weil pairing hyperelliptic curves pairing-based cryptosystems twisted curves

Periodic solutions of a 2.th-order nonlinear difference equation

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science china {2. 2010年第1期53卷 41-50页

作者： ZHOU Zhan 1, YU JianShe 1 & CHEN YuMing 2. school of mathematics and {2. science, {4. University, {4. 510006, china 2.Department of mathematics, Wilfrid Laurier University, Waterloo N2. 3C5, Canada 1. school of mathematics and {2. science Guangzhou University Guangzhou 510006 China2. Department of Mathematics Wilfrid Laurier University Waterloo N2L 3C5 Canada

In this paper, a 2.nth-order nonlinear difference equation is *** the critical point theory, we establish various sets of sufficient conditions of the nonexistence and existence of periodic *** obtained complement or ... 详细信息

关键词： periodic solution nonlinear difference equation critical point theory

A provable secure fuzzy identity based signature scheme

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science china({2. sciences) 2012年第9期55卷 2139-2148页

作者： WANG ChangJi 1,2.1 school of information {2. and Technology,Sun Yat-sen University,guangzhou 5102.5,{4. 2.Guangdong Province information Security Key Laboratory,Sun Yat-sen University,guangzhou 5102.5,{4. 1. school of information {2. and Technology Sun Yat-sen University Guangzhou 510275 China2. Guangdong Province Information Security Key Laboratory Sun Yat-sen University Guangzhou 510275 China

To use biometrics identities in an identity based encryption system,Sahai and Waters first introduced the notion of fuzzy identity based encryption(FIBE) in *** et *** it to digital signature and introduced the concept of fuzzy identity based signature(FIBS) in 2.08,and constructed an FIBS scheme based on Sahai and Waters's FIBE *** this paper,we further formalize the notion and security model of FIBS scheme and propose a new construction of FIBS scheme based on bilinear *** proposed scheme not only provides shorter public parameters,private key and signature,but also have useful structures which result in more efficient verification than that of Yang et al.'s FIBS *** proposed FIBS scheme is proved to be existentially unforgeable under a chosen message attack and selective fuzzy identity attack in the random oracle model under the discrete logarithm assumption.

关键词： identity based cryptosystem fuzzy identity based encryption fuzzy identity based signature

Leakproof secret sharing protocols with applications to group identification scheme

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science china({2. sciences) 2012年第5期55卷 1172-1185页

作者： TANG ChunMing 1,2.& GAO ShuHong 3 1 school of mathematics and {2. science,{4. University,{4. 510006,china 2.State Key Laboratory of {2. Security,Institute of Software science,Chinese Academy of sciences,Beijing 10004.,china 3 Department of Mathematical sciences,Clemson University,SC 2.634.USA 1. school of mathematics and {2. science Guangzhou University Guangzhou 510006 China2. State Key Laboratory of Information Security Institute of Software Science Chinese Academy of Sciences Beijing 100049 China3. Department of Mathematical Sciences Clemson University Clemson SC 29634 USA

In a traditional (t,n)-threshold secret sharing scheme,t or more honest participants can reconstruct the secret *** the reconstruction process,the individual shares and the secret key K are revealed,hence K is shared once *** this paper,we firstly give the definition of leakproof secret sharing scheme which is composed of a distribution protocol and a proof protocol,then propose two leakproof secret sharing protocols,a computationally secure protocol and an information-theoretically secure *** our protocols,t or more participants can jointly prove that they hold the secret K by using a multi-prover zero-knowledge argument of *** a result,the secret K will be shared for as many times as ***,each participant can detect the dealer in the distribution protocol from cheating,and any verifier can prevent non-qualified set of participants in proof protocol from *** an example of the practical impact of our work we use our techniques to construct group identification schemes with zero-knowledge.

关键词： secret sharing leakproof secret sharing multi-prover zero-knowledge argument proof of knowl-edge group identification scheme

Transitional function of DG to CA3 in the hippocampus

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Progress in Natural science:Materials International 2007年第12期17卷 1436-1444页

作者： Yan Chuankui1 and Liu Shenquan2.1. Department of mathematics, Hangzhou Normal University, Hangzhou 310036, china 2. Department of Applied mathematics, school of Mathematical {4.s, South china University of Technology, guangzhou 51064., china) Department of mathematics Hangzhou Normal University Hangzhou 310036 China Department of Applied mathematics School of Mathematical Sciences South China University of Technology Guangzhou 510640 China

Using single cell channel model, the transmission features of CA3-DG network in the hippocampus are investigated. The influence of the stimulation on discharge pattern of pyramidal neurons is analyzed, which shows that it starts with period spiking discharges, followed by period-doubling bifurcation to chaos, and period 3 discharge evolving into chaos, and ultimately a period of bursting discharges. By the synaptic model, the CA3-DG network model is constructed, which analyzes the summation of postsynaptic currents in the network, the influence of postsynaptic current on discharge rhythm as well as the mechanism of bursting discharges. The strong capacity of spatiotemporal encoding in the network indicates the features of CA3 network during the information transmission process in the hippocampus. The modeling result with time delay of the synaptic transmission is in accordance with the experimental phenomena of action potential in the hippocampus.

关键词： hippocampus CA3-DG period-doubling bifurcation chaos.