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Large-scale information entropy analysis of important sites in mature and precursor miRNA sequences

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science china(Life sciences) 2009年第8期52卷 771-779页

作者： DU JiangFeng1,2.WU YongJun2.ZHANG YinXia3,WU Lei1,2.WANG XiaoLong3,TAO ShiHeng1,2.1 Bioinformatics center,Northwest science and {2. university of Agriculture,Yangling 712.00,china 2.College of Life sciences,Northwest science and {2. university,Yangling 712.00,china 3 College of science,Northwest science and {2. university,Yangling 712.00,china Bioinformatics center Northwest Science and Technology University of Agriculture Yangling 712100 China College of Life sciences Northwest Science and Technology University Yangling 712100 China College of science Northwest Science and Technology University Yangling 712100 China

In order to find evidence of consistent sequence conservation or the base correlation degree in miRNA,some important sites in the sequences of reported miRNA and their precursors(pre-miRNA) were investigated via information entropy *** different groups of sites were obtained from special locations(head,tail) in miRNAs of different sources according to taxonomy(animal,plant and virus) and then analyzed by measuring the single base information redundancy(D1(L)) and the adjacent base related information redundancy(D2.L)).The results showed that D2.L) has more information than D1(L),though D1(L) changes roughly consistently with D2.L) in each *** pre-miRNAs are more conservative than those belonging to animals or *** addition,U is dominant in most sites compared with other *** was also found that in the middle of several groups,there were sites where miRNAs were cut down from pre-miRNAs by Enzyme Dicer which were significantly *** phenomenon shows that the conservatism is an aspect of the of miRNA and may be involved in the recognition and cutting by the *** results provided another perspective for understanding more about the primary structure of pre-miRNA.

关键词： miRNA conservative information entropy precursor evolution base correlation degree

Corner occupying theorem for the two-dimensional integral rectangle packing problem

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science china({2. sciences) 2012年第11期55卷 2466-2472页

作者： HUANG WenQi1,YE Tao1 & CHEN DuanBing2.1School of Computer science and technology,Huazhong {2. of science and technology,Wuhan 430074,china 2.eb sciences center,School of Computer science,{2. of Electronic science and technology of china,Chengdu 611731,china 1. School of Computer science and technology Huazhong University of Science and Technology Wuhan 430074 China2. Web Sciences Center School of Computer Science University of Electronic Science and Technology of China Chengdu 611731 China

This paper proves a corner occupying theorem for the two-dimensional integral rectangle packing problem,stating that if it is possible to orthogonally place n arbitrarily given integral rectangles into an integral rectangular container without overlapping,then we can achieve a feasible packing by successively placing a rectangle onto a bottom-left corner in the *** on this theorem,we might develop e?cient heuristic algorithms for solving the integral rectangle packing *** fact,as a vague conjecture,this theorem has been implicitly mentioned with different appearances by many people for a long time.

关键词： rectangle packing bottom-left corner occupying theorem NP hard

Interhemispheric atmospheric mass oscillation and its relation to interannual variations of the Asian monsoon in boreal summer

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science china Earth sciences 2010年第9期53卷 1343-1350页

作者： LU ChuHan, GUAN ZhaoYong & CAI JiaXi Key Laboratory of Meteorological Disaster of Ministry of Education and College of Atmospheric sciences, nanjing {2. of information science & technology, nanjing 2.0044, china 1. Key Laboratory of Meteorological Disaster of Ministry of Education and College of Atmospheric sciences Nanjing University of Information Science & Technology Nanjing 210044 China

Using NCEP/NCAR reanalysis and precipitation records of Chinese stations, we have investigated the relationship of interhemispheric oscillation of air mass (IHO) with global lower-level circulation and monsoon anomalies in boreal summer. Our results show that the summer IHO explains a greater portion of variance in the abnormal distribution of atmospheric mass over 30°S-60°N as well as the Antarctic. The IHO strongly correlates to the variations of sea level pressure (SLP) in these regions. It is shown that IHO has some influences on both atmospheric mass transports and water vapor fluxes over 30°S-60°N in association with three anomalous cyclonic circulations over land areas of the eastern hemisphere, which is in close relation to the changes in summer monsoon intensity in eastern Asia and western Africa. Composites of summer rainfall anomalies in china for high and low IHO-index years indicate that the eastern Asian summer monsoon is more intense, with positive precipitation anomaly centers in northern and northeastern parts of china, as opposed to the negative center over the mid-lower reaches of the Yangtze River (MLRYR) in stronger IHO years. In weak IHO years, a feeble summer monsoon appears in eastern Asia, leading to positive center of precipitation anomalies displaced into the MLRYR. Furthermore, a teleconnection in wind fields between the western African and eastern Asian monsoon regions was observed in the middle and higher troposphere in the scenario of IHO. The anomalous cyclonic (anticyclonic) circulations along the path of this Africa-East Asia teleconnection were found to be just over the diabatic heating (cooling) centers, suggesting that diabatic forcings are responsible for the formation of this Africa-East Asia teleconnection.

关键词： interhemispheric oscillation Asian monsoon precipitation china boreal summer

Accountability Analysis of Electronic Commerce Protocols by Finite Automaton Model

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Wuhan university Journal of Natural sciences 2004年第3期9卷 293-295页

作者： Xie Xiao-yao 1,2., Zhang Huan-guo 1 1. School of Computer, Wuhan university, Wuhan 430072. Hubei, china 2. Institute of {2. technology, Guizhou university of technology, Guiyang 550003, Guizhou, china Wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Guizhou university of technology Institute of Network Technology Guiyang Guizhou China (GRID:grid.443382.a) (ISNI:***) Wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The accountability of electronic commerce protocols is an important aspect to insures security of electronic transaction. This paper proposes to use Finite Automaton (FA) model as a new kind of framework to analyze the transaction protocols in the application of electronic commerce. Key words finite automaton - electronic commerce - nonrepudiation - information security CLC number TP 393. 08 Foundation item: Supported by the National Natural science Foundation of {2. (66973034, 90104005, 60373087)Biography: Xie Xiao-yao (1952.), male, Professor, Ph. D candidate, research direction: information security.

关键词： finite automaton electronic commerce nonrepudiation information security

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 102.49,china 2.Enhanced Oil Recovering Research center,china university of Petroleum,Beijing 102.49,china 3Faculty of Natural Resource&information technology,china university of Petroleum,Beijing 102.49,china 1. MOE Key Laboratory of Petroleum Engineering China University of Petroleum Beijing 102249 China2. Enhanced Oil Recovering Research Center China University of Petroleum Beijing 102249 China3. Faculty of Natural Resource & Information Technology China University of Petroleum Beijing 102249 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.H2. *** 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

Response synchronization: New progress in brain-visual information processing

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Chinese science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry , Institute of Atmospheric Physics , Chinese Academy of sciences , Beijing 10002., china 2. Commission of the National Natural science Foundation of china , Beijing 100083, china 3. The center of information science , Peking university, Beijing 100871, china 4. Open Laboratory of Visual information Processing , Institute of Biophysics , Chinese Academy of sciences , Beijing 100101, china State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National Natural science Foundation of china Beijing China The center of information {2. Peking University Beijing China Open Laboratory of Visual information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. Naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

Secure network coding in the presence of eavesdroppers

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science china({2. sciences) 2010年第3期53卷 648-658页

作者： LUO MingXing1,2.3, YANG YiXian1,2.3, WANG LiCheng1,2.3 & NIU XinXin1,2.3 1information Security center, State Key Laboratory of {2.ing and Switching technology, Beijing university of Posts and Telecommunications, Beijing 100876, china 2.ey Laboratory of {2. and information Attack and Defence technology of MOE, Beijing university of Posts and Telecommunications, Beijing 100876, china 3National Engineering Laboratory for Disaster Backup and Recovery, Beijing university of Posts and Telecommunications, Beijing 100876, china 1. information Security center State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China2. Key Laboratory of Network and Information Attack and Defence Technology of MOE Beijing University of Posts and Telecommunications Beijing 100876 China3. National Engineering Laboratory for Disaster Backup and Recovery Beijing University of Posts and Telecommunications Beijing 100876 China

Our concern, in the paper, is to construct information-theoretic secure network coding in the presence of eavesdroppers. Based on the generalized attack model and all-or-nothing transformation, the security of network coding in the generalized combination network can be characterized by the network capacity and the min-cut bound of wiretapping set from the source. Furthermore, it can be extended to any directed acyclic networks with single source. Compared with the traditional results, we construct information-theoretic secure network coding without additional encryptions and giving up any capacity.

关键词： all-or-nothing transformation secure network coding eavesdropping

Stability of linear discrete switched systems with delays based on average dwell time method

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science china({2. sciences) 2010年第6期53卷 1216-1223页

作者： WANG Yong 1 , WANG Wei 1 & LIU GuoPing 2.3 1 Research center of information and Control, Dalian {2. of technology, Dalian 11602., china 2.Faculty of Advanced technology, {2. of Glamorgan, Pontypridd, CF37 1DL, UK 3 CTGT center in Harbin Institute of technology, Harbin 150001, china 1. Research center of information and Control Dalian University of Technology Dalian 116024 China2. Faculty of Advanced Technology University of Glamorgan Pontypridd CF37 1DL UK3. CTGT Center in Harbin Institute of Technology Harbin 150001 China

This paper deals with the problem of exponential stability for a class of linear discrete switched systems with constant *** switched systems consist of stable and unstable *** on the average dwell time method, some switching signals will be found to guarantee exponential stability of these *** explicit state decay estimation is also given in the form of the solutions of linear matrix inequalities(LMIs).An example relating to networked control systems(NCSs) illustrates the effectiveness of the proposed method.

关键词： switched systems average dwell time time delay LMI

Formal analysis and design of multi-party fair exchange protocols

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science in china(Series F) 2006年第2期49卷 155-174页

作者： QING Sihan1,2.3 & LI Gaicheng1,3 1. Engineering Research center for information Security {2., Institute of Software, Chinese Academy of sciences, Beijing 100080, china 2. Beijing Zhongke Ansheng Corporation of information {2., Beijing 100080, china 3. Graduate School of the Chinese Academy of sciences, Beijing 100039, china 1. Engineering Research center for information Security {2. Institute of Software Chinese Academy of Sciences Beijing 100080 China 2. Beijing Zhongke Ansheng Corporation of information technology Beijing 100080 China 3. Graduate School of the Chinese Academy of sciences Beijing 100039 China

Based on the origin of message items and channel combination between transacting parties, and events and relations among events, this paper presents a concise, precise, and hierarchical model for general fair exchange protocols, formally specifies various security requirements which are able to reflect inherent requirements for fair exchange protocols more rigorously, and partition these security requirements with fine granularity. This work helps analyze, debug, and design multi-party fair exchange protocols more effectively and elaborately,

关键词： fair exchange logical protocol formal model security requirement.