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Relationship between precipitation and the infiltration depth over the middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley

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Progress in Natural Science:Materials International 2008年第9期18卷 1123-1128页

作者： Zhixin Hao a, Jingyun Zheng a, Quansheng Gea,, Xifeng Guoa,b a institute of Geographical Sciences and Natural resources Research, chinese academy of Sciences, 11A, Datun Road Anwai, Chaoyang District, beijing 100101, china b Graduate University of chinese academy of Sciences, beijing 100049, china institute of Geographical Sciences and Natural resources Research Chinese Academy of Sciences 11A Datun Road Anwai Chaoyang District Beijing 100101 China Graduate University of chinese academy of Sciences Beijing 100049 China

The purpose of the paper is to extract and make the best use of rainfall information contained in the chinese historical archives of Qing Dynasty, and reconstruct the precipitation series during *** study followed the Yu-Fen-Cun (rainfall infiltration depth) observation method in Qing Dynasty, to conduct soil infiltration experiment under the natural rainfall conditions during *** related parameters, such as precipitation, intensity, initial soil moisture content and infiltration depth have been measured at 10 stations (east of 105°E, 30°-40°N) with representative climatic conditions and soil physical texture in the middle and lower reaches of the Yellow River and Yangtze-Huaihe River *** statistical results indicate that precipitation is the primary infiuencing factor to infiltration depth and is positively correlated with the infiltration ***, the efiects of every factor on infiltration depth are significantly difierent between the middle and lower reaches of the Yellow River and Yangtze-Huaihe River ***, the relationship equations of precipitation and infiltration depth are established for each site, most of which can pass over 60% of the variance explanations and provide quantitative models to reconstruct the precipitation series using Yu-Fen-Cun records in Qing Dynasty.

关键词： Middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley Precipitation Infiltration depth Yu-Fen-Cun Climate reconstruction

A CLASS OF GENERALIZED MULTIPROCESSOR SCHEDULING PROBLEMS

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Systems Science and Mathematical Sciences 2000年第4期13卷 385-390页

作者： YANG Xiaoguang (Laboratory of Management, Decision and information System, institute of Systems Science, academy of Mathematics and Systems Science, chinese academy of Sciences, beijing 100080, china) 中科院系统科学所管理、决策与信息系统开放实验室北京 100080

The paper discusses a class of generalized multiprocessor scheduling problems which is to arrange some independent jobs on almost identical processors. Different from the classical multiprocessor scheduling, each job may only be processed by some processors, not all. In this paper, we first prove that the problems of minimization makespan and minimization total weighted completion time can be solved by the polynomial algorithms if all processing time are unit time. Then for arbitrary processing time, we try to analyze the worst performance of list schedule (LS) method and longest processing time(LPT) method when there are only two machines involved. We show that the bounds for LS and LPT are exactly two.

关键词： Unit execution time polynomial algorithm bound.

Numerical study on scanning radiation acoustic field in formations generated from a borehole

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Science china(Physics,Mechanics & Astronomy) 2005年第2期48卷 247-256页

作者： CHE Xiaohua1, ZHANG Hailan1, QIAO Wenxiao2 & JU Xiaodong2 1. institute of Acoustics, chinese academy of Sciences, beijing 100080, china 2. Faculty of Natural resources & information Technology, University of Petroleum, beijing 102249, china institute of Acoustics Chinese Academy of Sciences Beijing 100080 China Faculty of Natural resources & information Technology University of Petroleum Beijing 102249 China

Numerical study on scanning radiation acoustic field in formations generated by linear phased array transmitters in a fluid-filled borehole is carried out using a real axis integration (RAI) method. The main lobe width of the acoustic beams and the incident angle on the borehole wall can be controlled by means of adjusting parameters, such as the element number and the delay time between the neighboring array elements of linear phased array transmitter. The steered angle of longitudinal waves generated in the formation satisfies the Snell’s law for plane waves when the incident angle on the borehole wall is less than the first critical angle. When the lobe width of the acoustic beams is narrow and the steered angle is less than the first critical angle, the acoustic field in the formation can be approximately calculated given that the linear phased array is put in the formation without borehole. The technique of scanning radiation acoustic field can be applied to enhancing investigation resolution and signal-to-noise ratio in crosswell seismic survey and borehole acoustic reflection imaging.

关键词： formation, linear phased array transmitter, steered angle, RAI, scanning radiation.

Research on the Earth system multi-body force system dynamical model

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Science china(Technological Sciences) 2006年第z2期49卷 11-22页

作者： CHEN Xiaofei, BI Siwen, WU Fei & DONG Qianlin State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the institute of Remote Sensing Applications of chinese academy of Sciences and beijing Normal University, beijing 100101, china Laboratory of 3D information Access and Application of Capital Normal University, beijing 100037, china chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China beijing Normal Univ Beijing 100101 Peoples R China Capital Normal Univ Lab D Informat Access & Applicat 3 Beijing 100037 Peoples R China

This paper presents an overview of the binding force and freedom force of Earth system, and describes force moment to point and line and force system in the Earth system. It introduces the force theory of the Earth system multi-body force system from special or equivalent force system of Earth system mechanics, general force and no-power force of Earth system. Finally it describes the force and moment of nodes of Earth system and provides basic model for the research of the Earth system multi-body dynamics.

关键词： Earth system, multi-body system force, dynamics, basic models.

New application methods for word-oriented cryptographic primitives

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Science china(information Sciences) 2012年第9期55卷 2149-2160页

作者： YANG Yang 1,2,ZENG Guang 1,2,JIN ChengHui 1 & QU YunYing 1 1 Zhengzhou information Science and Technology institute,Zhengzhou 450002,china 2 State Key Laboratory of information Security,institute of Software,chinese academy of Sciences,beijing 100190,china 1. Zhengzhou information Science and Technology institute Zhengzhou 450002 China2. State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China

Modern software oriented symmetric ciphers have become a key feature in utilizing word-oriented cryptographic *** the output sequence,in the order of its generation,of a word-oriented cryptographic primitive in the same way as traditional bit-oriented primitives,we can expose the intrinsic weakness of these primitives,especially for word-oriented linear feedback shift registers,T-functions,and so *** new methods for using word-oriented cryptographic primitives are presented in this paper,that is,the extracted state method and cascading extracted coordinate *** a T-function as an example,we research the different cryptographic properties of the output sequences of the original method and the two proposed methods,focusing mainly on period,linear complexity,and k-error linear *** conclusions show that the proposed methods could enhance at low cost the cryptographic properties of the output *** a result,since the new methods are simple and easy to implement,they could be used to design new word-oriented cryptographic primitives.

关键词： stream cipher single cycle T-function linear complexity k-error linear complexity

ROBUST CONSENSUS AND SOFT CONTROL OF MULTI-AGENT SYSTEMS WITH NOISES

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Journal of Systems Science & Complexity 2008年第3期21卷 406-415页

作者： Lin WANG Lei GUO institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

This paper considers the problem of robust consensus for a basic class of multi-agent systems with bounded disturbances and with directed information flow. A necessary and sufficient condition on the robust consensus is first presented, which is then applied to the analysis, control and decision making problems in the noise environments. In particular, the authors show how a soft control technique will synchronize a group of autonomous mobile agents without changing the existing local rule of interactions, and without assuming any kind of connectivity conditions on the system trajectories.

关键词： Directed graph robust consensus soft control time-varying systems

Fog Detection over china's Adjacent Sea Area by using the MTSAT Geostationary Satellite Data

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Atmospheric and Oceanic Science Letters 2012年第2期5卷 128-133页

作者： LI Jun 1,2,HAN Zhi-Gang 3,CHEN Hong-Bin 1,ZHAO Zeng-Liang 3,and WU Hong-Yi 4 1 Laboratory for Middle Atmosphere and Global Environment Observation (LAGEO),institute of Atmospheric Physics,chinese academy of Sciences,beijing 100029,china 2 Graduate University of chinese academy of Sciences,beijing 100049,china 3 beijing institute of Applied Meteorology,beijing 100029,china 4 beijing Meteorological Bureau,beijing 100089,china [a] Laboratory for Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China[b] Graduate University of Chinese Academy of Sciences Beijing 100049 China[c] Beijing Institute of Applied Meteorology Beijing 100029 China[d] Beijing Meteorological Bureau Beijing 100089 China

A fog threshold method for the detection of sea fog from Multi-function Transport Satellite (MTSAT1R) infrared (IR) channel data is *** method uses principle component analysis (PCA),texture analysis,and threshold detection to extract sea fog information.A heavy sea fog episode that occurred over china's adjacent sea area during 7 8 April 2008 was detected,indicating that the fog threshold method can effectively detect sea fog areas nearly 24 hours a ***-1R data from March 2006,June 2007,and April 2008 were processed using the fog threshold method,and sea fog coverage information was compared with the meteorological observation report data from *** hit rate,miss rate,and false alarm rate of sea fog detection were 66.1%,27.3%,and 33.9%,*** results show that the fog threshold method can detect the formation,evolution,and dissipation of sea fog events over period of time and that the method has superior temporal and spatial resolution relative to conventional ship *** addition,through MTSAT-1R data processing and a statistical analysis of sea fog coverage information for the period from 2006 to 2009,the monthly mean sea fog day frequency,spatial distribution and seasonal variation characteristics of sea fog over china's adjacent sea area were obtained.

关键词： sea fog MTSAT geostationary satellite spatial distribution seasonal variation

Conus Peptides-A Rich Pharmaceutical Treasure

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Acta Biochimica et Biophysica Sinica 2004年第11期36卷 713-723页

作者： Cheng-Zhong WANG and Cheng-Wu CHIinstitute of Biochemistry and Cell Biology, Shanghai institute of Biological Sciences, the chinese academy of Sciences, Shanghai 200031, china institute of Neuroscience, the chinese academy of Sciences, Shanghai 200031, china institute of Protein Research, Tongji University, Shanghai 200092, china institute of Biochemistry and Cell Biology Shanghai Institute of Biological Sciences the Chinese Academy of Sciences institute of Neuroscience the Chinese Academy of Science institute of Protein Research Tongji University

Marine predatory cone snails (genus Conus) with over 500 species represent what is arguably the largest single genus of marine animals alive today. All Conus are venomous and utilize a complex mixture of Conus peptide... 详细信息

关键词： Conus peptide conotoxin neuropathic disorder pharmaceutical potency

Research progress in terahertz quantum cascade lasers

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Science china(information Sciences) 2012年第1期55卷 16-26页

作者： CAO JunCheng Key Laboratory of Terahertz Solid-State Technology,Shanghai institute of Microsystem and information Technology,chinese academy of Sciences,Shanghai 200050,china 1. Key Laboratory of Terahertz Solid-State Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

The terahertz(THz)quantum cascade laser(QCL)is a coherent THz source based on intersubband transitions of unipolar *** semiconductor lasers,THz QCLs are solid-state,electrically pumped,tunable,and can be easily *** paper reviews the state of the art for the design,operation temperature,and output power of THz *** applications in THz communication and imaging are also discussed.

关键词： terahertz quantum cascade laser communication imaging