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Lithosphere types in North china:Evidence from geology and geophysics

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Science china Earth Sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2, DENG Jinfu3. ZHOU Su3. LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3.1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 10003., china 2. Development and research center, china Geological Survey, Beijing 10003., china 3. china University of Geosciences, Beijing 100083. china 4. china University of Geosciences, Wuhan 43.074, china 5. information center of Ministry of Land and Resources, Beijing 100812. china 6. Institute of Geology, State Seismological Bureau, Beijing 100029, china Institute of Geology Chinese Academy of Geological Sciences Beijing China Development and research center China Geological Survey Beijing China china University of Geosciences Beijing China china University of Geosciences Wuhan China information center of Ministry of Land and Resources Beijing China Institute of Geology State Seismological Bureau Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

Distribution,formation and evolution of sand ridges on the East china Sea shelf

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Science china(Technological Sciences) 2010年第3期53卷 822-828页

作者： ZHAO RenBao 1,2,SUN HaiTao 3.WU YaSheng 3.&ZHAO ChuanFeng 1,2 1MOE Key Laboratory of Petroleum Engineering,china University of Petroleum,Beijing 102249,china 2 Enhanced Oil Recovering research {3.,china University of Petroleum,Beijing 102249,china 3.aculty of Natural Resource&information Technology,china University of Petroleum,Beijing 102249,china MOE Key Laboratory of Petroleum Engineering China University of Petroleum Beijing China Enhanced Oil Recovering research center China University of Petroleum Beijing China Faculty of Natural Resource & information Technology China University of Petroleum Beijing China

Influence of CO2 corrosion on reservoir mineralogical composition,pore structure and their mechanical characteristics was studied using XRD,SEM,rock tri-axial machine and core flow experimental *** was found that the corrosion effect was mainly attributed to rock texture and structure,fluid composition and external dynamical conditions in the experimental *** cores with bedding structures,their bedding surfaces were the preferential corrosion regions,because micro-cracks would evolve at these surfaces in the pressure-releasing ***,for cores with massive structures controlled by stable water environment,the CO2 corrosion would result in pore enlargement and secondary pore *** gas velocity from outlet showed sharp increase in the injection process of CO2-H2O *** could be explained by two changes caused by *** was the opening and closure of *** other was particle *** the corrosion time increased,both tensile strength and compressive strength decreased,which confirmed decrease of cementation *** should also be noted that permeability increase and micro-cracks generation would pose damage to the capacity of CO2 geological storage.

关键词： carbon dioxide geological storage mineralization enhanced oil recovery corrosion

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,Beijing 102249,china 2 Basin & Reservoir research {3.,china Petroleum University,Beijing 102249,china 3.State Key Laboratory of Petroleum Resource and Prospecting,china University of Petroleum,Beijing 102249,china 4 research {3. of CNOOC,Beijing 100027,china Key Lab of Geophysical Exploration of CNPC China Petroleum University Beijing China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing China Basin & Reservoir research center China Petroleum University Beijing China research center of CNOOC Beijing 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)

security model and modular design of fair authentication key exchange protocols

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Science china(information Sciences) 2010年第2期53卷 278-287页

作者： FENG DengGuo & CHEN WeiDong State Key Laboratory of information security, Institute of Software, Chinese Academy of Sciences, Beijing 100190, {3. State Key Laboratory of information security Institute of Software Chinese Academy of Sciences Beijing China

It is traditionally assumed that the legal two parties in authentication key exchange (AKE) communications are both credible. However, in more and more network applications nowadays, it is often required that such protocols be run under the circumstances where ones do not trust in each other. Therefore, in this paper we propose the idea of fair authentication key exchange (FAKE), which has not only the basic properties of AKE protocols, but also some new properties: the "session proof" embedded in the input of protocols by the customer; and if not revealed, the protocols have the deniability, otherwise the transcript of protocol is binding for the identifications. Such a method is capable of solving the contradiction between protecting privacy and the dissension on network service. Then the security model of FAKE protocols is formulated systematically and a flaw of the security model of current signature schemes proposed by Kudla is also corrected. Finally, a kind of FAKE protocol based on current signature schemes is designed and the mBJM-AK security, conditional deniability and fairness of FAKE protocols are proved in the random oracle model.

关键词： authentication key exchange protocols deniability fairness concurrent signature provable security

Polar differential power attacks and evaluation

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Science china(information Sciences) 2012年第7期55卷 1588-1604页

作者： TANG Ming 1 ,QIU ZhenLong 1 ,GAO Si 1,2 ,YI Mu 3.,LIU ShuBo 1 ,ZHANG HuanGuo 1 & JIN YingZhen 1 1 School of Computer Science,Wuhan University,Wuhan 43.072,china 2 State Key Laboratory of information security,Institute of Software,Chinese Academy of Sciences,Beijing {3.,china 3.Centre for Computer and information security research School of Computer Science and Software Engineering University of Wollongong,Wollongong,NSW 2522,Australia School of Computer Science Wuhan University Wuhan China State Key Laboratory of information security Institute of Software Chinese Academy of Sciences Beijing China Centre for Computer and information security research School of Computer Science and Software Engineering University of Wollongong Wollongong Australia

Side channel attacks (SCAs) on security software and hardware have become major concerns on computer and system *** existing SCAs generally require the knowledge of the corresponding cryptographic algorithm and implementation adopted in the target; therefore,they are not fully suitable for practical *** this paper,we propose a novel SCA-polar differential power attack (polar DPA).We found that DPA peaks have different biases for different cryptographic algorithms and *** on these biases,we can successfully attack a block cipher,assuming that the cipher algorithm uses a secret key in its first round,without the knowledge of the cipher algorithm or *** rounds can be treated as a black *** present a detailed theoretical analysis and experiment to demonstrate the correctness and efficiency of our ***,our scheme has demonstrated an improvement over the leakage evaluation scheme due to Ichikawa et al.(CHES 2005).Our evaluation method can be used in electronic design automatic (EDA) flows and can help security circuit designers to understand the data leakage due to SCAs.

关键词： computer security differential power attack side channel attack

The new interpretation of support vector machines on statistical learning theory

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Science china Mathematics 2010年第1期53卷 151-164页

作者： ZHANG ChunHua 1 , TIAN YingJie 2 & DENG NaiYang 3.1 School of information, Renmin University of china, Beijing 100872, china 2 {3. center on Fictitious Economy and Data Science, Chinese Academy of Sciences, Beijing 100080, china 3.College of Science, china Agricultural University, Beijing 100083. china School of information Renmin University of China Beijing China research center on Fictitious Economy and Data Science Chinese Academy of Sciences Beijing China College of Science China Agricultural University Beijing China

This paper is concerned with the theoretical foundation of support vector machines (SVMs). The purpose is to develop further an exact relationship between SVMs and the statistical learning theory (SLT). As a representative, the standard C-support vector classification (C-SVC) is considered here. More precisely, we show that the decision function obtained by C-SVC is just one of the decision functions obtained by solving the optimization problem derived directly from the structural risk minimization principle. In addition, an interesting meaning of the parameter C in C-SVC is given by showing that C corresponds to the size of the decision function candidate set in the structural risk minimization principle.

关键词： C-support vector classification the minimization principle of the structural risk KKT conditions

RRM:An incentive reputation model for promoting good behaviors in distributed systems

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Science in china(Series F) 2008年第11期51卷 1871-1882页

作者： ZHANG Hong1,2,DUAN HaiXin1,3.& LIU Wu1,3.1 Tsinghua National Laboratory for information Science and Technology,Tsinghua University,Beijing 100084,china 2 Department of Computer Science and Technology,Tsinghua University,Beijing 100084,china 3.Network research center,Tsinghua University,Beijing 100084,china Tsinghua National Laboratory for information Science and Technology Tsinghua University Beijing China Department of Computer Science and Technology Tsinghua University Beijing China Network research center Tsinghua University Beijing China

Reputation systems represent soft security mechanisms that complement traditional information security mechanisms. They are now widely used in online e-commerce markets and communities in order to stimulate good behaviors as well as to restrain adverse behaviors. This paper analyzes the limitations of the convers{3. reputation models and proposes an incentive reputation model called the resilient reputation model （RRM） for the distributed reputation systems. The objective of this reputation model is not only to encourage the users to provide good services and, therefore, to maximize the probability of good transaction outcomes, but also to punish those adverse users who are trying to manipulate the application systems. The simulation results indicate that the proposed reputation model （RRM） could effectively resist against the common adverse behaviors, while protecting the profits of sincere users from being blemished by those adversaries.

关键词： reputation model distributed system trust soft security

Waiting time in block fading MIMO systems with dynamic-depth interleaving

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Science china(information Sciences) 2010年第8期53卷 1622-1627页

作者： GUO HaiYou 1,2 , HU HongLin 1,2 & ZHANG Yan 3.1 Key Laboratory of Wireless Sensor Network & Communication, Shanghai Institute of Microsystem and information Technology, Chinese Academy of Sciences, Shanghai 200050, china 2 Shanghai research {3. for Wireless Communications, Shanghai 2003.5, china 3.Simula research Laboratory, Lysaka 13.5, Norway Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai China Shanghai research center for Wireless Communications Shanghai China Simula research Laboratory Lysaka Norway

Interleaving is an efficient measure to resolve the bursty errors in a block fading multiple-inputs multiple-outputs (MIMO) system. For the metrics of network layer, interleaving exerts two conflicting effects on the ultimate delay performance. Specifically, interleaving can advantageously reduce data transmit time. On the other hand, it comes at a cost, entailing an undesired delay penalty resulting from interleaving depth. Here, we exploit a unified model to accommodate these two conflicting effects, and derive the average waiting time in block fading MIMO systems with dynamic-depth interleaving. Such a unified model is developed with a combined method of both information theory and queueing theory. Therefore, the model is capable of characterizing the randomness of data arrival process, hence the nature of dynamic-depth interleaving. The methodology and the results are applicable to designing, evaluating, and tuning the practical interleaving systems.

关键词： dynamic-depth interleaving multiple-inputs multiple-outputs (MIMO) queueing analysis waiting time

Channel-aware and queue-aware joint-layer resource optimization for cognitive radio networks

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Science china(information Sciences) 2010年第12期53卷 2576-2583页

作者： GUO KunQi 1,2,SUN LiXin 1,LI Yong 2 & JIA ShiLou 3.1 School of Computer Science and Telecommunication Engineering,Jiangsu University,Zhenjiang 212.13.china 2 research {3. for Wireless Communication,Shanghai Institute of Microsystem and information Technology,Chinese Academy of Sciences,Shanghai 200050,china 3.Communication research {3.,Harbin Institute of Technology,Harbin 150001,china School of Computer Science and Telecommunication Engineering Jiangsu University Zhenjiang China research center for Wireless Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai China Communication research center Harbin Institute of Technology Harbin China

An optimization model is derived to maximize the utilization efficiency of the idle channels of primary users(PU) in cognitive radio *** the optimization model,Lyapunov optimization method is used to allocate the idle channels of PU to secondary user(SU) most *** time distribution of the idle channels of PU is predicted by a low-pass time *** algorithm is proposed to implement the optimization *** algorithm is efficient because of using a greedy selection *** efficiency of the algorithm is demonstrated by mathematic analyses and simulation results.

关键词： cognitive radio networks Lyapunov optimization resource utilization primary user secondary user