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Predicting Polymerase Ⅱ Core Promoters by Cooperating Transcription Factor Binding Sites in Eukaryotic Genes

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 250-258页

作者： Xiao-Tu MA, Min-Ping QIAN*, and Hai-Xu TANG1 School of Mathematical sciences, peking university and center for Theoretical Biology, peking university, beijing 100871, China 1Department of Computer science and Engineering, university of California, San Diego, La Jolla CA 92093.0114, USA School of Mathematical sciences Peking University and Center for Theoretical Biology Peking UniversityBeijing 100871 China Department of Computer science and Engineering University of CaliforniaSan Diego La Jolla CA 92093-0114 USA

Several discriminate functions for predicting core promoters that based on the potential cooperation between transcription factor binding sites (TFBSs) are discussed. It is demonstrated that the promoter predicting accuracy is improved when the cooperation among TFBSs is taken into consideration. The core promoter region of a newly discovered gene CKLFSF1 is predicted to locate more than 1.5 kb far away from the 5' end of the transcript and in the last intron of its upstream gene, which is experimentally confirmed later. The core promoters of 3.02 human RefSeq sequences, obtained by extending the mRNAs in human genome sequences, are predicted by our algorithm, and there are about 60% of the predicted core promoters locating within the ± 500 bp region relative to the annotated transcription start site.

关键词： promoter transcription factor binding site transcription start site gene finding

Constraints on smoothness parameter and dark energy using observational H(z) data

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Research in Astronomy and Astrophysics 2011年第2期11卷 125-136页

作者： Hao-Ran Yu1,Tian Lan1,Hao-Yi Wan2,Tong-Jie Zhang1,3.and Bao-Quan Wang4 1 Department of Astronomy,beijing Normal university,beijing 100875,China 2 Business Office,beijing Planetarium,beijing 100044,China 3.center for High Energy Physics,peking university,beijing 100871,China 4 Department of Physics,Dezhou university,Dezhou 253.23.China Department of Astronomy Beijing Normal University Beijing 100875 China Business Office Beijing Planetarium Beijing 100044 China center for High Energy Physics Peking University Beijing 100871 China Department of Physics Dezhou University Dezhou 253023 China

With large-scale homogeneity,the universe is locally inhomogeneous,clustering into stars,galaxies and larger *** property is described by the smoothness parameter α which is defined as the proportion of matter in the form of intergalactic *** we consider the inhomogeneities over a small scale,there should be modifications of the cosmological distances compared to a homogenous *** and Roeder developed a second-order ordinary differential equation（D-R equation） that describes the angular diameter distance-redshift relation for inhomogeneous cosmological ***,we may obtain the D-R equation for observational H（z） data（OHD）.The density-parameter ΩM,the state of dark energy ω,and the smoothness-parameter α are constrained by a set of OHD in a spatially flat XCDM universe as well as a spatially flat XCDM *** using a χ2 minimization method,we get α = 0.81＋0.19-0.20 and ΩM = 0.3.＋0.12-0.06 at the 1σ confidence *** we assume a Gaussian prior of ΩM = 0.26 ± 0.1,we get α = 0.93.0.07-0.19 and ΩM = 0.3.＋*** the XCDM model,α is constrained to α≥ 0.80 but ω is weakly constrained around-1,where ω describes the equation of state of the dark energy（pX = ωρX）.We conclude that OHD constrains the smoothness parameter more effectively than the data of SNe Ia and compact radio sources.

关键词： cosmology -- dark energy -- cosmological parameters

Pre-LOI trajectory maneuvers of the CHANG'E-2 libration point mission

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science China(information sciences) 2012年第6期55卷 1249-1258页

作者： WU WeiRen 1,LIU Yong 2,3.LIU Lei 2,3.ZHOU JianLiang 3.TANG GeShi 2,3.& CHEN YongZhi 3.1 Chinese Lunar Exploration and Space Project center,beijing 10003.,China 2 science and Technology on Aerospace Flight Dynamics Laboratory,beijing 100094,China 3.beijing Aerospace Control center,beijing 100094,China 1. Chinese Lunar Exploration and Space Project center Beijing 100037 China2. Science and Technology on Aerospace Flight Dynamics Laboratory Beijing 100094 China3. Beijing Aerospace Control Center Beijing 100094 China

This paper addresses pre-LOI (before Lissajous orbit insertion) trajectory maneuvers for the libration point mission of CHANG'E-2,which is the first Chinese satellite to fly to the Sun-Earth L2 libration point and the first satellite ever to fly to the L2 point from lunar ***,a transfer trajectory for the mission is designed based on InterPlanetary Superhighway theory under the constraint of the remaining propellant,TT&C (telemetry,track and command) and sunlight *** effects of trajectory maneuver errors on the mission are also ***,based on the analysis results,the article investigates the trajectory maneuver schemes for the lunar escape and transfer trajectory maneuvers employing mathematical models and operational *** mission status based on our maneuver schemes is then presented,and the results of control operation and corresponding analysis are provided in ***,the future trajectory maneuver in the Lissajous orbit is *** to the analysis of the CHANG'E-2 TT&C data,the trajectory maneuver schemes proposed in the article work properly and efficiently.

关键词： CHANG’E-2 libration point trajectory maneuver escape trajectory transfer trajectory

The coupling instability of Rossby and topographic Rossby waves in the equatorial area

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science China Earth sciences 2005年第10期48卷 1792-1801页

作者： CHAO Jiping1,2, LIU Lin1,3.& YU Weidong1 1. Laboratory of Marine science and Numerical Modeling, State Oceanic Administration, Qingdao 266061, China 2. National Research center for Marine Environmental Forecasts, State Oceanic Administration, beijing 100081, China 3. Ocean{3. of China, Qingdao 266003. China Laboratory of Marine science and Numerical Modeling State Oceanic Administration Qingdao China National Research center for Marine Environmental Forecasts State Oceanic Administration beijing China Ocean university of China Qingdao China

In case of considering the fact that the tropical ocean thermocline or the lower at-mosphere height field has the meridional variation, the topographic Rossby wave will be excited. Also the background geostrophic current emerges. Under such conditions, the topographic Rossby wave can interact with the classical Rossby wave at some parameter band and thus brings a new kind of instability, which may be of potential application in understanding some phenomena of the ENSO cycle.

关键词： thermocline variation, equatorial jet, Rossby wave, topographic Rossby wave, coupling instability

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(22.5) bulk metallic glass up to 24 GPa

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science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2 , ZHAN Zaiji 2 , LIU Jing 3., YUN Jinku 1 , SUN Liling 2 , LIU Riping 1 , ZHANG Jun 2 & WANG Wenkui 1, 2 1. Key Laboratory of Metastable Materials science and Technology, Yanshan university, Qinhuangdao 066004, China 2. center for Condensed Matter Physics, Institute of Physics, Chinese Academy of sciences, beijing 100080, China 3. BSRF, Institute of High Energy Physics, Chinese Academy of sciences, beijing 10003., China 1. Key Laboratory of Metastable Materials science and Technology Yanshan University 066004 Qinhuangdao China 2. center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass (BMG) is investigated at room temperature up to 24 GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

Multiparty simultaneous quantum identity authentication with secret sharing

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science China(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3.& ZHANG Xing4,5 1 College of Computer science and Technology,beijing university of Technology,beijing 100022,China 2 State Key Laboratory of information Security (Graduate university of the Chinese Academy of sciences),beijing 100049,China 3.School of science,beijing university of Posts and Telecommunications,beijing 100876,China 4 Institute of Electronic Technology,information Engineering university,Zhengzhou 450004,China 5 Trusted Computing Laboratory,beijing university of Technology,beijing 100022,China College of Computer science Technology Beijing University of Technology Beijing 100022 China State Key Laboratory of information Security [Graduate university of the Chinese Academy of sciences] Beijing 100049 China School of science Beijing University of Posts Telecommunications Beijing 100876 China Institute of Electronic Technology Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan university Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2, 3.,HUANG Zhiqin 2, 3. 4 1. The Faculty of Geography and Resources science, Sichuan Normal university, Chengdu 610066, Sichuan, China 2. Institute of Mountain Hazards and Environment, Chinese Academy of sciences, Chengdu 610041, Sichuan, China 3. Graduate university of the Chinese Academy of sciences, beijing 100049, China 4. information center of Land and Resources Department of Sichuan Province, Chengdu 610041, Sichuan, China The Faculty of Geography Resources science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate university of the Chinese Academy of sciences 100049 Beijing China information center of Land Resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 3.°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Bifurcation stabilization of nonlinear systems by dynamic output feedback with application to rotating stall control

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science China(information sciences) 2012年第1期55卷 200-213页

作者： CHEN PengNian1,QIN HuaShu2,WANG Yong3.HONG YiGuang2 1Department of Mathematics,China Jiliang university,Hangzhou 3.0018,China 2Institute of Systems science,The Chinese Academy of sciences,{3. 100080,China 3.epartment of Mechanics,peking university,{3. 100871,China 1. Department of Mathematics China Jiliang University Hangzhou 310018 China2. Institute of Systems Science The Chinese Academy of Sciences Beijing 100080 China3. Department of Mechanics Peking University Beijing 100871 China

The paper deals with the problem of stabilization of stationary bifurcation solutions of nonlinear systems via dynamic output *** is emphasized that the parameter of the system is not directly *** introduce the concepts of uniform observability of the inverse of a function of state and input and N-order-input-to-state bifurcation *** on the concepts,we propose a new method for designing dynamic compensators that guarantee bifurcation stability for the closed-loop *** an example,we apply the general theory to active control of rotating stall in axial flow compressors by designing a stabilizing dynamic compensator for the three-state Moore-Greitzer model with a class of cubic compressor characteristics.

关键词： bifurcation control uniform observability dynamic output feedback rotating stall

Architecture and key technologies of grid geographic information system

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science China(Technological sciences) 2008年第S1期51卷 102-113页

作者： FANG Yu,HUANG Zhou,CHEN Bin,WU Lun & YIN DaFei Institute of Remote Sensing and Geographic information System,peking university,{3. 100871,China Institute of Remote Sensing and Geographic information System Peking University Beijing 100871 China

The highly efficient and stable collaborative computation platform for geospatial information can be constructed on the basis of Grid computing technology,com-bined with Peer-to-Peer (P2P) computing technology and geospatial database technology. This paper proposed the architecture and key technologies of the Grid GIS (Geographic information System) incorporated with P2P structure,and corre-spondingly a Grid GIS prototype named Nebula was designed and then imple-mented. Nebula is a suite of middleware for geospatial Grid computing,which could be deployed onto various service nodes in network. Based on Grid protocols and infrastructure,Nebula provides invocation interfaces to users in form of Grid services. By using P2P message based communication mechanism,complex geospatial computation tasks could be accomplished by Nebula in a collaborative way. This paper introduced Nebula's architecture and key modules,and according to experimental data,we discussed the Grid GIS's advantages,application scenar-ios and future directions.

关键词： Grid GIS distributed geospatial computing Peer-to-Peer computing