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The roles of a decision support system in applying forest ecosystem management in Northeast china

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Science china.Technological Sciences) 2006年第z1期49卷 9-18页

作者： DAI Limin, ZHENG Bofu, Guofan Shao & ZHOU Li state key lab.of Systems Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, beijing 100085, china.Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, china.Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Graduate University of Chinese Academy of Sciences, beijing 100101, china 1. state key lab.of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China2. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China3. Department of Forestry and Natural Resources Purdue University West Lafayette IN 47907 USA4. Graduate University of Chinese Academy of Sciences Beijing 100101 China

Forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in china.is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools availab.e to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, FORESTAR, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of FORESTAR.

关键词： forest functions, forested landscapes, forest services, forest models, geographic information systems.

Measuring-basis-encrypted six-state quantum key distribution scheme

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Progress in Natural Science:Materials International 2006年第1期16卷 84-89页

作者： CHEN Pan1, DENG Fuguo1, WANG Pingxiao1 and LONG Guilu1,2 (key lab.ratory for Quantum information and Measurements and Department of Physics, Tsinghua University, beijing 100084, china.2. key lab.ratory for Atomic and Molecular NanoSciences, Tsinghua University, beijing 100084, china. [a]Department of Physics Tsinghua University Key Laboratory for Quantum Information and Measurements Beijing China [b]Tsinghua University Key Laboratory for Atomic and Molecular NanoSciences Beijing China

A six-state quantum key distribution scheme with measuring-basis encryption technique, which is based on the six-state protocol and the MBE protocol, is proposed. In this modified six-state quantum key distribution protocol, Alice and Bob use a control key to synchronize the use of their measuring-basis so that they always use the same measuring-basis. This modified six-state quantum key distribution protocol retains the advantage of higher security and at the same time has a higher efficiency.

关键词： quantum key distribution measuring-basis encrypted six-state security.

Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

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Science china.Technological Sciences) 2006年第z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, china.School of Forestry, Northeast Forestry University, Harbin 150040, china.state key lab.of Systems Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, beijing 100085, china.Graduate University of Chinese Academy of Sciences, beijing 100039, china 1. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. School of Forestry Northeast Forestry University Harbin 150040 China 3. state key lab.of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 4. Graduate University of Chinese Academy of Sciences Beijing 100039 China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of china.(FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was44.2%, much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is availab.e.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

Monitoring of rice crop using ENVISAT ASAR data

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Science china.Earth Sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2, SUN Guoqing1,3 & PANG Yong4 1. state key lab.ratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of Sciences, beijing 100101, china.2. Graduate University of Chinese Academy of Sciences, beijing 100039, china.3. Department of Geography, University of Maryland, College Park, MD 20742, USA 4. Forest Remote Sensing lab. Research Institute of Forest Resource and information Technology, Chinese Academy of For-estry, beijing 100091, china 1. state key lab.ratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. Graduate University of Chinese Academy of Sciences Beijing 100039 China 3. Department of Geography University of Maryland College Park MD 20742 USA 4. Forest Remote Sensing lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

The Research and Development of Worm Defense Strategies

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The Research and Development of Worm Defense Strategies

Robust multiuser MIMO scheduling algorithms with imperfect CSI

2010 3rd IEEE International Conference on Computer Science and information Technology—ICCSIT 2010

作者： Liuqi 1 1 state key lab.ratory of information security Graduate University of Chinese Academy of Science beijing china.Ma Guoqing 2 2 National key lab.ratory of Science and Technology on information System security beijing china

The deterioration of worm propagation on internet in recent years has pushed the research in the field of worm defense, as a result there are coming up plenty of worm defense strategies. This paper refers to make the systematic study of the complete worm defense strategies and provide taxonomy of worm defense system strategies according to the key factors of each defense category. As guideline for the design of worm defense, we compare the present evaluation of the worm defense strategies, and give a highlight on the trendy of worm defense in the future at the end.

关键词： worm defense evaluation math modeling simulation

来源： cnki会议评论

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Science china.information Sciences) 2012年第4期55卷 815-826页

作者： MAO JunLing 1,3,GAO JinChun 1,3,LIU YuanAn 1,3,XIE Gang 2,3 & ZHANG Jian 1,3 1 School of Electronic Engineering,beijing University of Posts and Telecommunications,beijing 100876,china.2 School of information and Communication Engineering,beijing University of Posts and Telecommunications,beijing 100876,china.3 key lab.of Universal Wireless Communications,Ministry of Education,beijing University of Posts and Telecommunications,beijing 100876,china 1. School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China3. Key Lab of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China2. School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Robust multiuser multiple-input-multiple-output (MIMO) scheduling algorithms are proposed in this *** imperfect channel state information (CSI),traditional scheduling algorithms for the multiuser MIMO system based on the zero forcing precoding scheme will lose some performance due to the multi-user interference (MUI).In order to improve the system average throughput,we study the robust multiuser MIMO scheduling problem with imperfect *** the average capacity formula,we derive a robust factor which can transform the robust multiuser MIMO scheduling problem into the traditional one,thus most existing non-robust scheduling algorithms can be robust if this factor is *** results show that compared with the traditional algorithms,the proposed robust algorithms can improve the system average throughput significantly under the CSI error environment.

关键词： multiuser MIMO (MU-MIMO) scheduling robust imperfect CSI

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 lab.ratory 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.lab.ratory 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.

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改进的基于漫游场景的认证密钥交换协议

通信学报 2009年第S2期30卷 61-68页

作者：周涛徐静中国科学院研究生院信息安全国家重点实验室北京100190 信息安全共性技术国家工程研究中心北京100190 中国科学院软件研究所信息安全国家重点实验室北京100190

由于动态性和易受攻击的结构特性,无线网络环境下认证协议的设计面临新的挑战。2006年,全球移动网络漫游场景下的2个双向认证密钥交换协议被提出。经过分析发现,这2个协议都会遭受到一些实际的攻击。进一步的,2个改进的协议被提出用于... 详细信息

由于动态性和易受攻击的结构特性,无线网络环境下认证协议的设计面临新的挑战。2006年,全球移动网络漫游场景下的2个双向认证密钥交换协议被提出。经过分析发现,这2个协议都会遭受到一些实际的攻击。进一步的,2个改进的协议被提出用于抵御这些攻击。这2个协议不仅保留了原方案的优点,还提高了第2个方案的效率。

关键词：无线通信漫游认证密钥交换匿名性

Robust Threshold Guillou-Quisquater Signature Scheme

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Robust Threshold Guillou-Quisquater Signature Scheme