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Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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science china(Technological sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2. HUANG GuanHua1,2.& QU ZhongYi3.1 center for Agriculture Water {2., china Agricultural University, {3. 100083. china 2.chinese-Israeli International center for {2. and Training in Agriculture, china Agricultural University, {3. 100083. china 3.Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, china 1. center for Agriculture Water research China Agricultural University Beijing 100083 China 2. chinese-Israeli International center for {2. and Training in Agriculture China Agricultural University Beijing 100083 China 3. Water Conservancy and Civil Engineering College Inner Mongolia Agricultural University Hohhot 010018 China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for application (VBA). The model was calibrated and validated with independent data sets. application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

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A formal method to real-time protocol interoperability testing

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science in china(Series F) 2008年第11期51卷 1723-1744页

作者： WANG ZhiLiang1,3.YIN Xia2.3.& JING ChuanMing2.3.1 Network research center,Tsinghua University,beijing 100084,{3. 2.Department of Computer science and Technology,Tsinghua University,beijing 100084,{3. 3.Tsinghua National Laboratory for Information science and Technology(TNList) ,beijing 100084,{3. 1. Network research center Tsinghua University Beijing 100084 China 3. Tsinghua National Laboratory for Information science and Technology (TNList) Beijing 100084 China 2. Department of Computer science and Technology Tsinghua University Beijing 100084 China

Interoperability testing is an important technique to ensure the quality of implementations of network communication protocol. In the next generation Internet protocol, real-time applications should be supported effectively. However, time constraints were not considered in the related studies of protocol interoperability testing, so existing interoperability testing methods are difficult to be applied in real-time protocol interoperability testing. In this paper, a formal method to real-time protocol interoperability testing is proposed. Firstly, a formal model CMpTIOA （communicating multi-port timed input output automata） is defined to specify the system under test （SUT） in real-time protocol interoperability testing; based on this model, timed interoperability relation is then defined. In order to check this relation, a test generation method is presented to generate a parameterized test behavior tree from SUT model; a mechanism of executability pre-determination is also integrated in the test generation method to alleviate state space explosion problem to some extent. The proposed theory and method are then applied in interoperability testing of IPv6 neighbor discovery protocol to show the feasibility of this method.

关键词： protocol testing interoperability testing real-time testing test generation timed input output automata(TIOA)

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Aerosol retrieval over land by exploiting the synergy of TERRA and AQUA MODIS DATA

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science china Earth sciences 2006年第6期49卷 641-649页

作者： TANG Jiakui1, XUE Yong1,2. YU Tong3. GUAN Yanning1, CAI Guoyin1 & HU Yincui1 1. State Key Laboratory of Remote Sensing science, Jointly Sponsored by the Institute of Remote Sensing {2.s of chinese {3. of sciences and beijing Normal University, beijing 100101, china 2. Department of Computing, London Metropolitan University, 166-2.0 Holloway Road, London N7 8DB, UK 3. beijing Environmental Monitor center, beijing 100044, china 1. 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 2. Department of Computing London Metropolitan University 166-220 Holloway Road London N7 8DB UK 3. beijing Environmental Monitor {2. Beijing 100044 China

Aerosol retrieval over land from satellite remotely sensed data remains internationally a difficult task. By using MODIS data, the Dark Dense Vegetation (DDV) algorithm aerosol distribution and properties retrieval over land has shown excellent competence. However, this algorithm is re-stricted to lower surface reflectance such as water bodies and dense vegetation, which limits its actual application, and is unable to be used for high reflective surface such as over urban areas. In this paper, we introduce a new aerosol retrieval model by exploiting the Synergy of TERRA and AQUA MODIS data (SYNTAM), which can be used for various ground surfaces, including for high reflective surface. Preliminary validations have been carried out by comparing with AERONET measured data, which shows good accuracy and promising potential. Further research work is undergoing.

关键词： aerosol retrieval, aerosol optical thickness, MODIS, TERRA, AQUA.

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Single crystal β-Ga_2._3. Cr grown by floating zone technique and its optical properties

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science china(Technological sciences) 2007年第1期50卷 51-56页

作者： ZHANG JunGang1, 2. LI Bin3. XIA ChangTai1, XU Jun1, DENG Qun4, XU XiaoDong1, WU Feng1, XU WuSheng4, SHI HongSheng4, PEI GuangQing1, 2.& WU YongQing1,2.1 Shanghai Institute of Optics and Fine Mechanics, chinese {2. of sciences, Shanghai 2.1800,{3. 2.Graduate School of the chinese {2. of sciences, beijing 10003.,{3. 3.Shanghai Institute of Applied Physics, chinese {2. of sciences, Shanghai 2.1800,{3. 4 GE ({13.) research and Development center Co. Ltd., Shanghai 2.12.3.{3. 1. Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate School of the chinese academy of {2.s Beijing 100039 China 3. Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China 4. GE (china) research and Development {2. Co. Ltd. Shanghai 201203 China

β-Ga2.3. Cr single crystals were grown by floating zone technique. Absorption spectra and fluorescence spectra were measured at room temperature. The values of field splitting parameter Dq and Racah parameter B were obtained by the peak values of absorption spectra. The value 10Dq/B=2.0}14 manifests that in β-Ga2.3.crystals Cr3. ions are influenced by low energy crystal field. After high temperature annealing in air, the Cr3. intrinsic emission was enhanced and the green lumines-cence disappeared. The strong and broad 691 nm emission was obtained at 42. nm excitation due to the electron transition occurred from 4T2.to 4A2. The studies manifest that the β-Ga2.3.crystals have the potential application for tunable laser.

关键词： β-Ga2.3. Cr single crystals floating zone technique tunable laser spectrum.

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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 {2. and Technology,Tsinghua University,beijing 100084,china 2.Department of Computer {2. and Technology,Tsinghua University,beijing 100084,china 3.Network research center,Tsinghua University,beijing 100084,china 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 {2. Tsinghua University Beijing 100084 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 conversational 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

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Ab-initio molecular dynamics simulation on nano-system under external pressure

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science china Mathematics 2004年第z1期47卷 92-100页

作者： Jl Min, SUN Deyan & GONG XingaoSurface Physics Laboratory and Department of Physics, Fudan University, Shanghai 2.043., china Institute of Solid State Physics, {2. academy of {3.s, Hefei 2.0}03., china Interdisciplary center for Theoretical studies, {2. academy of {3.s,{12., china Fudan Univ Surface Phys Lab Shanghai 200433 Peoples R China Fudan Univ Dept Phys Shanghai 200433 Peoples R China chinese Acad Sci Inst Solid State Phys Hefei 230031 Peoples R China chinese Acad Sci Interdisciplinary Ctr Theoret Studies Beijing 100080 Peoples R China

A new constant-pressure molecular dynamics (MD) method is developed to simulate the dynamic behavior and structure transition of finite system under external pressure. In this method, no artificial parameter is introduced and the computation overheads are very small. As an application, a hard-soft transition of single wall carbon nanotube (SWCNT) under external pressure is found, which is in agreement with the experiments.

关键词： phase transition, simulation, nano-particles

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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,{2. Petroleum University,beijing 102.49,{2. 2.Basin & Reservoir {3. center,{2. Petroleum University,beijing 102.49,{2. 3.State Key Laboratory of Petroleum Resource and Prospecting,{2. University of Petroleum,beijing 102.49,{2. 4 {3. center of CNOOC,beijing 10002.,{2. 1. Key Lab of Geophysical Exploration of CNPC China Petroleum University Beijing 102249 China 3. State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China 2. Basin & Reservoir research center China Petroleum University Beijing 102249 China 4. research center of CNOOC Beijing 100027 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)

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The application of hyperspectral remote sensing to coast environment investigation

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Acta Oceanologica Sinica 2009年第2期28卷 1-13页

作者： ZHANG Liang ZHANG Bin CHEN Zhengchao ZHENG Lanfen TONG Qingxi State Key Laboratory of Remote Sensing science Institute of Remote Sensing Applications Chinese Academy of Science Beijing 100101 China Naval Institute of Hydrographic Surveying and Charting Tianjin 300061 China center for Earth Observation and Digital Earth Chinese Academy of Science Beijing 100190 China

Requirements for monitoring the coastal zone environment are first summarized. Then the appli- cation of hyperspectral remote sensing to coast environment investigation is introduced, such as the classification of coast beaches and bottom matter, target recognition, mine detection, oil spill identification and ocean color remote sensing. Finally, what is needed to follow on in application of hyperspectral remote sensing to coast environment is recommended.

关键词： hyperspectral remote sensing coastal zone ocean color remote sensing

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Cause of winter gravity wave spectrum saturation

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science china Earth sciences 2005年第10期 236-242页

作者： WU Yongfu & XU Jiyao Laboratory for space Weather, center for space {3. and Applied research, chinese academy of {3.s, beijing 100080, china

This paper utilizes horizontal velocity measurements observed from 19 chaff rockets and nearly simultaneous temperature measurements collected from 19 falling sphere rockets to study the cause of winter gravity wave spectrum saturation. Results suggest that strong hori-zontal velocity shears larger than 0.04 s?1 are observed to be present at various heights near the winter mesopause. On one single chaff rocket flight, an extremely strong horizontal velocity shear as high as 0.3. s?1 is observed at 87.4 km and is believed to be the strongest value ever meas-ured in the mesosphere. These strong horizontal velocity shears, together with Brunt-V?is?l? frequency squared obtained from the temperature profile, act collectively to yield two dynamical instability regions of Richardson number smaller than 1/4, suggesting that the saturated gravity wave spectrum observed by the chaff rockets in winter is a result of dynamical instability.

关键词： winter spectrum strong shear dynamical instability spectrum saturation.

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Comparison of dark energy models:A perspective from the latest observational data

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中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1631-1645页

作者： LI Miao1,2.LI XiaoDong2.3.& ZHANG Xin1,4 1Kavli Institute for Theoretical Physics china,{2. academy of {3.s,beijing 100190,china 2.ey Laboratory of Frontiers in Theoretical Physics,Institute of Theoretical Physics,{2. academy of {3.s,beijing 100190,china 3.nterdisciplinary center for Theoretical Study,University of {3. and Technology of china,Hefei 2.0}02.,china 4Department of Physics,College of {3.s,Northeastern University,Shenyang 110004,china 1. Kavli Institute for Theoretical Physics china Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China3. Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei 230026 China4. Department of Physics College of Sciences Northeastern University Shenyang 110004 China

We compare some popular dark energy models under the assumption of a flat universe by using the latest observational data including the type Ia supernovae Constitution compilation,the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey,the cosmic microwave background measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observations and the determination of H0 from the Hubble space *** comparison statistics such as the Bayesian and Akaike information criteria are applied to assess the worth of the *** statistics favor models that give a good fit with fewer *** on this analysis,we find that the simplest cosmological constant model that has only one free parameter is still preferred by the current *** other dynamical dark energy models,we find that some of them,such as the αdark energy,constant w,generalized Chaplygin gas,Chevalliear-Polarski-Linder parametrization,and holographic dark energy models,can provide good fits to the current data,and three of them,namely,the Ricci dark energy,agegraphic dark energy,and Dvali-Gabadadze-Porrati models,are clearly disfavored by the data.

关键词： dark energy models observational constraints model comparison information criteria

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