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Extraction of LUCC with different methods and threshold value

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中国有色金属学会会刊：英文版 2005年第S1期15卷 236-239页

作者： WANG Ping~(1,2), ZHENG Yong-guo~1, LIN Zong-jian~2, ZHANG Ji-xian~2, ZHOU Chun-yan~1 (1. Shandong University of Science and Technology, Taian 271019, china 2. Chinese Academy of surveying and mapping, {3. 10003., china) Shandong Univ Sci & Technol Tai An 271019 Peoples R China Chinese Acad surveying & mapping Beijing 100039 Peoples R China

The research of land use and land cover (LUCC) is an important aspect in the global change research. The goal of this study is to find methods of extraction of LUCC’s change outlined and change type from remotely sensed data. Take the country of Fengxian in Shanghai as an example, it was supposed two steps to finish extraction of LUCC information: the first step was to use different methods, which is used to outline change areas; the second step include methods of false composing of two-temporal and threshold value. Through combining two methods, a model rule is built and the LUCC product is obtained, four kinds of change type within the study area are given, and the results are obvious. Finally, the results support the application of the high resolution image and tasseled cap composition (greenness and wetness) in the specific regional too.

关键词： different method land use and land cover change threshold tasseled cap

Review on abort trajectory for manned lunar landing mission

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Science china(Technological Sciences) 2010年第10期53卷 2691-2698页

作者： XI XiaoNing1, HUANG WenDe2 & WANG Wei2,3.1 College of Mechatronics Engineering and Automation, National University of Defense Technology, Changsha 410073. china 2 College of Aerospace and Material Engineering, National University of Defense Technology, Changsha 410073. china 3.School of surveying and Spatial Information System, University of New South Wales, Sydney, NSW 2052, Australia 1. College of Mechatronics Engineering and Automation National University of Defense Technology Changsha 410073 China2. College of Aerospace and Material Engineering National University of Defense Technology Changsha 410073 China3. School of Surveying and Spatial Information System University of New South Wales Sydney NSW 2052 Australia

Abort trajectory is a passage that ensures the astronauts to return safely to the earth when an emergency occurs. Firstly,the essential elements of mission abort are analyzed entirely based on summarizing the existing studies. Then,abort trajectory requirement and rational selection for different flight phases of typical manned lunar mission are discussed specifically. Considering a trade-off between the two primary constrains of an abort,the return time of flight and energy requirement,a general optimizing method for mission abort is proposed. Finally,some suggestions are given for china’s future manned lunar landing mission.

关键词： manned lunar landing mission abort trajectory design free return trajectory

Three-dimensional geodetic deformation surveying for Naner area in Daqing oilfield

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中国有色金属学会会刊：英文版 2005年第S1期15卷 112-115页

作者： LIU Xing-quan~(1, 2), LIU Shao-xuan~2, ZHANG Zhi-wen~3. XU Hai~4, LIU Jian-jun~5 (1. Department of Earth Science, Zhejiang University, Hangzhou 3.0027, china 2. The Second Oil Recovery Plant of Daqing Oilfields Co Ltd, Daqing 163.14, china 3. Daqing Logging and Testing Services Company, Daqing 163.11, china 4. Longnan Telephone Station of Daqing Communications Center, Daqing 163.10, china 5. Department of Civil Engineering, Wuhan Polytechnic University, Wuhan 43.023. china) Zhejiang Univ Dept Earth Sci Hangzhou 310027 Peoples R China Second Oil Recovery Plant of Daqing Oilfields Co Daqing 163414 Peoples R China Daqing Commun Ctr Longnan Telephone Stn Daqing 163410 Peoples R China Daqing Logging & Testing Serv Co Daqing 163411 Peoples R China Wuhan Polytech Univ Dept Civil Engn Wuhan 430023 Peoples R China

Geodetic deformation severely affects the development of the oilfield and probably causes casing damage or abandonment of injection wells and producers. Therefore, it is meaningful to survey and study three-dimensional geodetic deformation in the process of the oilfield development. In order to study this issue, 11-year long term surveying of three-dimensional geodetic deformation has been carried out while developing Naner area in Daqing oilfield. Basic rules of 3.D geodetic deformation have been obtained through surveying. Results show that production and injection under high pressure may cause the changes of surface elevation, and geodetic deformation correlates with simultaneous formation pressure. Precautions and relative technological measurements have been put forward in the waterflood development in Naner region and provide theoretical guidelines for the production and casing preservation of the oilfield. Finally, surveying results are interpreted by porous elastic theory. Mathematical model to calculate 3.D geodetic deformation is put forward in the course of the oilfield development.

关键词： Daqing oilfield geodetic deformation producer water injector mathematical model

基于H.225.0Annex G协议的域间路由寻址策略

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通信学报 2008年第7期29卷 69-74页

作者：李锐喻占武武汉大学测绘遥感信息工程国家重点实验室湖北武汉430079

针对多媒体通信中域间访问效率较低的问题,基于H.225Annex G协议,研究ITU-T E.164码建议电话号码编码方式和DNS域名解析方法,采用地址驱动的路由寻址机制,提出一种基于准同域的域间动态路由寻址策略(qhAD策略)。此策略在上下级管理域之... 详细信息

针对多媒体通信中域间访问效率较低的问题,基于H.225Annex G协议,研究ITU-T E.164码建议电话号码编码方式和DNS域名解析方法,采用地址驱动的路由寻址机制,提出一种基于准同域的域间动态路由寻址策略(qhAD策略)。此策略在上下级管理域之间使用H.225Annex G中的描述符分发类信令交换域地址模板以获取实时的域间地址信息,使各级管理域能保存一个与祖先信息有关的路由地址表,呼叫发起时向最近准同域级的祖先直接请求地址解析,从而使"准同域"类的呼叫路由寻址请求在一个相对小的域内得以解决。通过对策略延迟时间性能分析和模型仿真研究,得出qhAD寻址策略可以大大减少寻址响应的延迟,减少路由寻址中对信道的占用,减轻通信信道的负担。

关键词：多媒体通信寻址管理域域间路由 H.225 Annex G协议

The Mathematic Models of the Kalman Filtering for Across-Fault Measurement

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Earthquake Research in china 1994年第3期8卷 92-103页

作者： You Lilan,Liu Dajie,Huang Jia’na,Liu Xue and Zhou KechangInstitute of Crustat Dynamics,SSB,beijing 100085,china Wuhan Technical University of surveying and {3.,Wuhan 43.070,china National Center for Seismic Data and Inforraanon,SSB,beijing 1.0045,china

This paper makes a probe into the application of the Kalman filtering method to the data processing of across-fault *** the basis of statistical regression,the mathematic and stochastic models of filtration are established by combining the regression method with Kalman *** the filtering computation,not only the randomness of fault movements but also the time-dependent variation of environmental effects have been taken into *** use of the adaptive filtering method,an estimation of the dynamic noise variance matrix is obtained through *** for one measuring line(leveling line or baseline),two measuring lines(both leveling lines or both baselines)and four measuring lines(two leveling lines and two baselines)are derived and established *** means of these models,the data of across-fault measurements can be processed dynamically in real-time to provide the filtered values of height difference between benchmarks or baseline length at different time

关键词： Across-fault measurement Kalman filtration State equation Observational equation Initial state Dynamic noise

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基于DEM和地物分类信息的SAR图像模拟

系统仿真学报 2009年第8期21卷 2437-2440页

作者：秦志远张宝印靳国旺李贺向茂生张薇信息工程大学测绘学院郑州450052 西安测绘研究所西安710054 中国科学院电子学研究所微波成像技术国家级重点实验室北京100190

SAR图像模拟对于雷达系统设计、SAR图像几何及辐射校正等具有重要意义。针对正侧视SAR成像的几何特点,顾及地面坡度、地物类型、成像距离等因素对雷达波后向散射强度的影响,采用强度积分策略,设计了基于DEM和地物分类信息的SAR图像模拟... 详细信息

SAR图像模拟对于雷达系统设计、SAR图像几何及辐射校正等具有重要意义。针对正侧视SAR成像的几何特点,顾及地面坡度、地物类型、成像距离等因素对雷达波后向散射强度的影响,采用强度积分策略,设计了基于DEM和地物分类信息的SAR图像模拟方案;通过仿真实验得到了满意的SAR模拟图像,验证了该模拟方案的正确性和有效性。

关键词：数字高程模型地物分类合成孔径雷达图像模拟

The Application Study about Ground-Based GPS Precipitable Water Vapor in Shijiazhuang and Qinhuangdao Region

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The Application Study about Ground-Based GPS Precipitable Wa...

Automatic generalization of metro maps based on dynamic segmentation

2010 3.d IEEE International Conference on Computer Science and Information Technology—ICCSIT 2010

作者： Wang Yong 1 2 1.College of Traffic and surveying Hebei Polytechnic University Tangshan china 2.Key Laboratory of Mine Spatial Information Technologies (Henan Polytechnic University Henan Bureau of surveying and {3.) State Bureau of surveying and {3. Jiaozuo china Ding Keliang School of surveying and Civil Spatial Information beijing University of Civil Engineering and Architecture beijing china He Rong School of surveying and Land Infomation Engineering Henan Polytechnic University Jiaozuo china Liu Yanping College of Traffic and surveying Hebei Polytechnic University Tangshan china

Water vapor is a highly variable parameter in atmospheric processes and it plays a crucial role in atmospheric motions on a wide range of scales in space and time. GPS technique has been widely used in retrieving precipitable water vapor. Firstly the article has retrieved precipitable water vapor of Qinhuangdao and Shijiazhuang stations by GPS technique. Then it has researched two aspects of precipitable water vapor. One is the spatial and temporal distribution characters of precipitable water vapor;the other is the relation between precipitable water vapor and actual rainfall. The value of GPS precipitable water vapor of Shijiazhuang is higher than the value of GPS precipitable water vapor of Qinhuangdao, which is accord to the formula that the precipitable water vapor is reduced from south to north. During the different time of a day, there are differ degree fluctuate which the min value present to morning and the max value present to evening. It also compared the GPS precipitable water vapor and actual rainfall. Although the time of max value about rainfall is not identical to the time of max value about precipitable water vapor, rainfall has occurred mostly in the time while the value of precpitable water vapor is high.

关键词： Global positioning system Precipitable water vapor Zenith tropospheric delay Zenith wet delay

来源： cnki会议评论

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Science china(Technological Sciences) 2010年第S1期53卷 158-165页

作者： DONG WeiHua 1,TIAN Yuan 2 & ZHANG Yi 2 1 Institute of Geography and Remote Sensing,beijing Normal University,beijing 100875,china 2 Institute of Remote Sensing and Geographic Information System,Peking University,beijing 100871,china 1. Institute of Geography and Remote Sensing Beijing Normal University Beijing 100875 China 2. Institute of Remote Sensing and Geographic Information System Peking University Beijing 100871 China

A metro map is usually optimized for the readability of connections and transportation networks *** order to assure good readability and meet aesthetic considerations,a set of principles for good metro map layout are *** to these principles,a new methodology based on dynamic segmentation is presented to produce the metro maps ***,routes are constructed according to the line attribute similarity and geometry *** a set of cartographic generalization methods about the shape,angle,length,and topology are presented for these *** method is validated by beijing metro plan *** the experiment results,it can be concluded that this new method is more effective than the static segmentation method to produce metro maps with better readability for route plans.

关键词： metro maps generalization dynamic segmentation visualization

Multiple constraints QoS multicast routing optimization algorithm in MANET based on GA

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Progress in Natural Science:Materials International 2008年第3期18卷 331-336页

作者： Baolin Sun a,c, Shangchao Pi b, Chao Gui a, Yue Zeng d, Bing Yan a, Wenxiang Wang c, Qianqing Qin c a School of Computing, Hubei University of Economics, Wuhan 43.205, china b College of Science, Zhongyuan University of Technology, Zhengzhou 450007, china c State Key Laboratory of Information Engineering in surveying, {3. & Remote Sensing, Wuhan University, Wuhan 43.079, china d Department of Computing, Jiangxi Vocational College of Finance and Economics, Jiangxi 3.2000, china School of Computing Hubei University of Economics Wuhan 430205 China College of Science Zhongyuan University of Technology Zhengzhou 450007 China State Key Laboratory of Information Engineering in surveying Mapping & Remote Sensing Wuhan University Wuhan 430079 China Department of Computing Jiangxi Vocational College of Finance and Economics Jiangxi 332000 China

Usually multiple quality of service (QoS) guarantees are required in most multicast applications. This paper presents a multiple con-straints algorithm for multicast traffic engineering in mobile ad hoc networks (MANET). The proposed algorithm is a new version of multiple constraints QoS multicast routing optimization algorithm in MANET based on genetic algorithm (MQMGA). The proposed MQMGA can optimize the maximum link utilization, the cost of the multicast tree, the selection of the long-life path, the average delay and the maximum end-to-end delay. Experimental result shows that the approach is efficient, has promising performance in multicast traffic engineering and for evaluating the route stability in dynamic mobile networks.

关键词： Ad hoc network Multicast routing QoS Genetic algorithm