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SEMI-OPENNESSAND ALMOST-OPENNESS OF INDUCED MAPPINGS 被引量:1
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作者 HuangXianjiu ZengFanping ZhangGengrong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第1期21-26,共6页
Given a mapping f between continua.Let 2f and C(f) mean the induced mappings between hyperspaces.Relations are studied under the conditions:f is semi-open(almost open,respectively),2f is semi-open(almost open,respecti... Given a mapping f between continua.Let 2f and C(f) mean the induced mappings between hyperspaces.Relations are studied under the conditions:f is semi-open(almost open,respectively),2f is semi-open(almost open,respectively) and C(f) is semi-open(almost open,respectively). 展开更多
关键词 Continuum HYPERSPACE induced mapping semi-openness almost open.
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TRANSFER OPEN OR CLOSED SETVALUED MAPPING AND GENERALIZ-ATION OF H-KKM THEOREM WITH APPLICATIONS
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作者 李秉友 苏家宝 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第10期981-987,共7页
In this paper ,we introduce a class of generalized mapping called transfer open orclosed valued mapping to generalize the KKM theorem on H-space.Then asapplications,using our H-KKM theorem,we prove some coincidence th... In this paper ,we introduce a class of generalized mapping called transfer open orclosed valued mapping to generalize the KKM theorem on H-space.Then asapplications,using our H-KKM theorem,we prove some coincidence theorems.matching theorems and vector valued minimax inequalities which generalize slightly thecorresponding results in[1,2,4,5,6,7]. 展开更多
关键词 transfer closed or open setvalued mapping coincidence theorem.H-KKM mapping matching theorem
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Utilization of Open Source Spatial Data for Landslide Susceptibility Mapping at Chittagong District of Bangladesh—An Appraisal for Disaster Risk Reduction and Mitigation Approach
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作者 Md. Ashraful Islam Sanzida Murshed +4 位作者 S. M. Mainul Kabir Atikul Haque Farazi Md. Yousuf Gazi Israt Jahan Syed Humayun Akhter 《International Journal of Geosciences》 2017年第4期577-598,共22页
Since creation of spatial data is a costly and time consuming process, researchers, in this domain, in most of the cases rely on open source spatial attributes for their specific purpose. Likewise, the present researc... Since creation of spatial data is a costly and time consuming process, researchers, in this domain, in most of the cases rely on open source spatial attributes for their specific purpose. Likewise, the present research aims at mapping landslide susceptibility at the metropolitan area of Chittagong district of Bangladesh utilizing obtainable open source spatial data from various web portals. In this regard, we targeted a study region where rainfall induced landslides reportedly causes causalities as well as property damage each year. In this study, however, we employed multi-criteria evaluation (MCE) technique i.e., heuristic, a knowledge driven approach based on expert opinions from various discipline for landslide susceptibility mapping combining nine causative factors—geomorphology, geology, land use/land cover (LULC), slope, aspect, plan curvature, drainage distance, relative relief and vegetation in geographic information system (GIS) environment. The final susceptibility map was devised into five hazard classes viz., very low, low, moderate, high, and very high, representing 22 km2 (13%), 90 km2 (53%);24 km2 (15%);22 km2 (13%) and 10 km2 (6%) areas respectively. This particular study might be beneficial to the local authorities and other stake-holders, concerned in disaster risk reduction and mitigation activities. Moreover this study can also be advantageous for risk sensitive land use planning in the study area. 展开更多
关键词 Susceptibility mapping open Source Spatial Data Heuristic Model Chittagong METROPOLITAN Area GEOGRAPHIC Information System (GIS) Disaster Risk Reduction
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Mapping Spatial Data on the Web Using Free and Open-Source Tools: A Prototype Implementation
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作者 Sunil Pratap Singh Preetvanti Singh 《Journal of Geographic Information System》 2014年第1期30-39,共10页
There is a growing need for web-based geographic information systems for easy and fast dissemination, sharing, displaying and processing of spatial information. The tremendous growth in the use of web and open-source ... There is a growing need for web-based geographic information systems for easy and fast dissemination, sharing, displaying and processing of spatial information. The tremendous growth in the use of web and open-source geospatial resources has sparked development of web-based spatial applications to address multidisciplinary issues with spatial dimensions. This paper presents the integration of open-source geospatial tools and web technology to visualize and interact with spatial data using web browser. The goal of this paper is to implement a prototype system for web-based mapping by providing step-by-step instructions in order to encourage the eager developers and interested readers to publish their maps on the web with no prior technical experience in map servers. The implementation of mapping prototype shows the utilization of open-source geospatial tools which results in a rapid implementation with minimal or no software input cost. 展开更多
关键词 open-SOURCE TECHNOLOGY WEB-BASED mapping WEB TECHNOLOGY GEOGRAPHIC Information System Spatial Application
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Mapping the Flood Risk Exposure Using Open-Source Geospatial Tools and Techniques: A Case of Gampaha Divisional Secretariat Division, Sri Lanka
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作者 Sundaralingam Suthakaran Sauri Jayakody +2 位作者 Shyamantha Subasinghe Nileesha Seneviratne Ranjith Alahakoon 《Journal of Geoscience and Environment Protection》 2022年第10期18-31,共14页
The use of open-source data and tools in disaster exposure mapping is presented in this paper. Disaster exposure is a collection of the element at risk to potential loss. Gampaha divisional secretariat (DS) is a study... The use of open-source data and tools in disaster exposure mapping is presented in this paper. Disaster exposure is a collection of the element at risk to potential loss. Gampaha divisional secretariat (DS) is a study area laid on the lower part of the Attanagalu Oya river basin. As the geospatial tools, OpenStreetMap (OSM), Java OpenStreetMap (JOSM), QGIS, GPS Essentials, and Open Map Kit (OMK) are used. The elements of disaster exposure, including the number of people or types of assets, are surveyed and inventoried using the OSM platforms. Local, national, and international agencies produce and evaluate the data. The study developed spatial data for building footprints of 165,000 households, street lengths of 2300 km, hospital units of 16, and utility units of 2300. This could overcome the main challenges of exposure mapping in the area. The procedure developed in the exposure mapping can be used in a data-sparse environment. Exposure mapping is generally used to estimate the impact of hazards or disasters, which are essential in effective disaster management. How are there still remaining challenges in disaster exposure mapping such as less awareness about the mapping procedure, lack of government support, internet access, hardware, and inability to understand the value of exposure mapping? 展开更多
关键词 Spatial Data Disaster Management Exposure mapping open-Source Software
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GENERAL OPEN MAPPING THEOREMS FOR LINEAR TOPOLOGICAL SPACES
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作者 丘京辉 《Acta Mathematica Scientia》 SCIE CSCD 1998年第3期241-248,共8页
In this paper, the author establishs general open mapping theorems for continuous, weakly continuous, closed and weakly singular linear maps respectively. From these general theorems, he deduces a lot of specific open... In this paper, the author establishs general open mapping theorems for continuous, weakly continuous, closed and weakly singular linear maps respectively. From these general theorems, he deduces a lot of specific open mapping theorems, which include some well-known theorems and some new interesting results. Particularly the author gives the extensions of Husain's open mapping theorem and Adasch's open mapping theorem. 展开更多
关键词 locally convex spaces DUALS barrelled spaces Mackey spaces open mapping theorems
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基于Open Street Map数据的地理信息分析与提取技术 被引量:4
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作者 任常青 陈杰 +1 位作者 査祝华 周晓光 《测绘标准化》 2017年第4期24-27,共4页
Open Street Map作为一个开放众源地理信息数据平台,其数据覆盖全球多个国家,对其数据结构的深入研究和分析有助于提取更多的地理信息数据。在简要介绍OSM数据结构分析的基础上,探讨OSM数据的特点及数据分析、提取的处理技巧。这些技术... Open Street Map作为一个开放众源地理信息数据平台,其数据覆盖全球多个国家,对其数据结构的深入研究和分析有助于提取更多的地理信息数据。在简要介绍OSM数据结构分析的基础上,探讨OSM数据的特点及数据分析、提取的处理技巧。这些技术有助于根据不同行业应用方向对地理信息数据进行按需提取处理,也有助于编写软件对OSM数据进行批量转换。 展开更多
关键词 open STREET map 数据分析 信息提取 要素表达 属性表达 关键字识别 格式转换
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SEVERAL GENERAL OPEN MAPPING THEOREMS
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作者 丘京辉 《苏州大学学报(自然科学版)》 CAS 1994年第2期176-178,共3页
Several general open mapping theorems for continuous linear maps, weakly continuous linear maps and closed linear maps are established respectively. From these general forms, a lot of specific open mapping theorems ca... Several general open mapping theorems for continuous linear maps, weakly continuous linear maps and closed linear maps are established respectively. From these general forms, a lot of specific open mapping theorems can be deduced. 展开更多
关键词 图论 凸空间 拓扑结构 线性映射
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Development of Web Mapping Application for Spatial Ecotourism Information Using QGIS Plugin and Freely Available Web Platforms in North West Highlands of Ethiopia a Case Study: Chokie Mountain Watersheds 被引量:1
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作者 Mengesha Endalew Wobetu Shiferaw Abinet Kindie 《Advances in Internet of Things》 2019年第3期50-61,共12页
Ecotourism is a sustainable, green and smokeless industry of the society by providing alternative source to the livelihood and local community, in order to re-naturalize the environment to bring the man closer to the ... Ecotourism is a sustainable, green and smokeless industry of the society by providing alternative source to the livelihood and local community, in order to re-naturalize the environment to bring the man closer to the natural environment. The use of web application has changed the way tourists gather information about tourist attraction spots of the research area. The aim of the study is to assess and identify ecotourism attraction sites of Chokie Mountain watersheds for touristic activities to develop a web-based GIS mapping portal for the improvement of nature-based ecotourism activities. The web-based GIS portal for Web Mapping Application is available for the user with the skills necessary to create standard web mapping services. We have implemented web mapping services based on formal cartographic visualization rules in the open source QGIS software and threejs JavaScript plugin. Threejs plugin is used for 3D visualization, interaction and export terrain data, map canvas image and vector data to HTML page and JS. The result of web-based GIS portal supports spatial and non-spatial database of tourist attraction and tourist service data with attractive user interface. 展开更多
关键词 ECOTOURISM Chokie MOUNTAIN Watersheds SPATIAL mapping Qgis open Source Software Qgis2threejs Plugins
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On Some Properties of Neutrosophic Semi Continuous and Almost Continuous Mapping
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作者 Bhimraj Basumatary Nijwm Wary +1 位作者 Jeevan Krishna Khaklary Usha Rani Basumatary 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第2期1017-1031,共15页
The neutrality’s origin,character,and extent are studied in the Neutrosophic set.The neutrosophic set is an essential issue to research since it opens the door to a wide range of scientific and technological applicat... The neutrality’s origin,character,and extent are studied in the Neutrosophic set.The neutrosophic set is an essential issue to research since it opens the door to a wide range of scientific and technological applications.The neutrosophic set can find its spot to research because the universe is filled with indeterminacy.Neutrosophic set is currently being developed to express uncertain,imprecise,partial,and inconsistent data.Truth membership function,indeterminacymembership function,and falsitymembership function are used to express a neutrosophic set in order to address uncertainty.The neutrosophic set producesmore rational conclusions in a variety of practical problems.The neutrosophic set displays inconsistencies in data and can solve real-world problems.We are directed to do our work in semi-continuous and almost continuous mapping on the basis of the neutrosophic set by observing these.Since we are going to study the properties of semi continuous and almost continuous mapping,we present the meaning of N-semi-open set,N-semi-closed set,N-regularly open set,N-regularly closed set,N-continuous mapping,N-open mapping,N-closed mapping,Nsemi-continuous mapping,N-semi-open mapping,N-semi-closed mapping.Additionally,we attempt to demonstrate a portion of their properties and furthermore referred to some examples. 展开更多
关键词 N-regularly open set N-regularly closed set N-semi-continuous mapping N-almost continuous mapping
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Dynamics of Open Systems with Affine Maps
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作者 张大剑 刘崇龙 仝殿民 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第4期13-16,共4页
Many quantum systems of interest are initially correlated with their environments and the reduced dynamics of open systems are an interesting while challenging topic. Affine maps, as an extension of completely positiv... Many quantum systems of interest are initially correlated with their environments and the reduced dynamics of open systems are an interesting while challenging topic. Affine maps, as an extension of completely positive maps, are a useful tool to describe the reduced dynamics of open systems with initial correlations. However, it is unciear what kind of initial state shares an affine map. In this study, we give a sumcient condition of initial states, in which the reduced dynamics can always be described by an affihe map. Our result shows that if the initial states of the combined system constitute a convex set, and if the correspondence between the initial states of the open system and those of the combined system, defined by taking the partial trace, is a bijection, then the reduced dynamics of the open system can be described by an affine map. 展开更多
关键词 Dynamics of open Systems with Affine maps
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基于Teigha.NET和MapWinGIS的多源异构测绘数据管理系统设计与实现 被引量:2
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作者 何清 《安徽地质》 2023年第2期158-161,共4页
遥感和计算机技术为传统测绘行业带来了新的发展机遇,测绘观测手段的多样化使得测绘数据种类逐渐增加,形成了海量的多源异构数据。传统数据存储管理方式难以有效支撑大数据的存储和高效处理分析,为解决这一难题,本研究提出了一种多源异... 遥感和计算机技术为传统测绘行业带来了新的发展机遇,测绘观测手段的多样化使得测绘数据种类逐渐增加,形成了海量的多源异构数据。传统数据存储管理方式难以有效支撑大数据的存储和高效处理分析,为解决这一难题,本研究提出了一种多源异构数据统一整合方法。采用C#语言、PostgreSQL数据库、MapWinGIS二次开发和Teigha.NET二次开发等多种开发手段,并结合混合编程方式开发了多源异构测绘数据管理系统。系统完全使用开源软件进行二次开发,脱离了AutoCAD等商业软件环境,针对不同空间基准、不同格式的测绘数据,实现了多源异构数据的结构转换及坐标转换,对多源异构测绘数据的存储和有效利用具有一定的参考价值。 展开更多
关键词 多源异构 测绘数据 GIS 数据管理 开源软件
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基于ES景观美学服务制图的城市绿色开敞空间系统构建--以富顺县新湾片区为例
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作者 赵珂 夏清清 《中国园林》 CSCD 北大核心 2024年第2期43-49,共7页
在城市绿色开敞空间系统网络化构建的探讨中,针对从自然生态系统本身出发、以绿地廊道连接绿地斑块的生态网络化构建方法容易出现预期结果远离人口集聚地、不易为人所用的空间不匹配问题,靶向构建自然生态保护利用与人类社会需求相互匹... 在城市绿色开敞空间系统网络化构建的探讨中,针对从自然生态系统本身出发、以绿地廊道连接绿地斑块的生态网络化构建方法容易出现预期结果远离人口集聚地、不易为人所用的空间不匹配问题,靶向构建自然生态保护利用与人类社会需求相互匹配的绿色开敞空间系统目标,引入生态系统服务概念,遵循其提供的以“服务流”链接自然生态供给与人类社会需求的级联框架,运用网络科学的中心度量方法,创新性建立由“挖掘城市绿色开敞空间系统自然生态系统服务潜能的景观美学服务供给制图-评估城市绿色开敞空间系统社会需求的景观美学服务需求制图-权衡城市绿色开敞空间系统的景观美学服务流制图”三部分组成的城市绿色开敞空间系统构建景观美学服务“供需流级联”网络制图方法,促成城市绿色开敞空间系统网络不仅将破碎的生态环境恢复为一个连续整体自然生态系统,还具有匹配自然生态供给与人类社会需求的内在联系,推动人居环境绿化“从自然生态内在保护到价值外显利用”的积极生态保护转向。 展开更多
关键词 风景园林 城市绿色开敞空间 生态系统服务 景观美学服务 空间制图
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基于CiteSpace的露天矿爆破技术知识演化和趋势分析
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作者 周玉祥 韩心宇 +2 位作者 赵玉 郭立华 周佳峥 《爆破》 CSCD 北大核心 2024年第1期210-220,共11页
为了研究露天矿爆破技术的发展轨迹和热点变化规律,在中国学术期刊出版总库(CNKI)中选取“露天矿”并含“爆破”检索条件,获得1116篇有效期刊文献作为样本。通过利用CNKI的文献可视化分析报告和CiteSpace这一可视化知识图谱工具,对我国... 为了研究露天矿爆破技术的发展轨迹和热点变化规律,在中国学术期刊出版总库(CNKI)中选取“露天矿”并含“爆破”检索条件,获得1116篇有效期刊文献作为样本。通过利用CNKI的文献可视化分析报告和CiteSpace这一可视化知识图谱工具,对我国露天矿爆破研究领域的发展现状、分布特征、研究热点和前沿趋势进行了全面而深入的研究和分析。研究表明:露天矿爆破研究主要分为:(1)露天矿爆破理论的确立和发展阶段(2010年前)、(2)现代技术运用和创新阶段(2010—2015年)、(3)绿色智能精细化发展阶段(2015年至今)3个阶段;学科分布主要是矿业工程和工业通用技术与设备;发文期刊主要是《爆破》、《工程爆破》以及其他矿业工程领域的期刊;研究作者及机构主要是矿业相关高等学校教师以及企业、研究院研究人员;研究主题主要包括爆破工艺过程中的爆破设计软件开发与应用,孔网参数、炸药单耗、装药结构等爆破参数优化,深孔爆破、台阶爆破、抛掷爆破、预裂爆破等爆破方式,爆破振动的控制与监测,数值模拟、人工智能算法的应用,爆破质量原因分析及爆破效果评价。未来的露天矿爆破将继续朝着自动化、智能化、精确化和环境友好化的方向发展,通过技术创新和多学科融合,为矿山行业提供更高效、安全、可持续的爆破解决方案。 展开更多
关键词 露天矿 爆破 CITESPACE 知识图谱 中国知网(CNKI)
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露天煤矿环境下基于LiDAR/IMU的紧耦合SLAM算法研究 被引量:2
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作者 马宝良 崔丽珍 +1 位作者 李敏超 张清宇 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第3期236-244,共9页
随着人工智能和无人驾驶等相关学科的快速发展,煤矿装备的智能化和无人化成为了新的趋势。智能设备的应用将大幅提高煤矿作业的生产力以及人员安全性。露天煤矿地形复杂,与城市环境相比无明显的几何特征,具有分段相似性,利用现有以激光... 随着人工智能和无人驾驶等相关学科的快速发展,煤矿装备的智能化和无人化成为了新的趋势。智能设备的应用将大幅提高煤矿作业的生产力以及人员安全性。露天煤矿地形复杂,与城市环境相比无明显的几何特征,具有分段相似性,利用现有以激光雷达为主的同时定位与建图(Simultaneous Localization and Mapping,SLAM)方案在该环境下易出现定位漂移和建图误差较大等现象。针对上述问题,提出了一种基于激光雷达(Light Detection and Ranging,LiDAR)和惯导(Inertial Measurement Unit,IMU)紧耦合的SLAM算法,该算法使用LiDAR和IMU两种传感器作为数据输入,对数据进行预处理,前端利用迭代扩展卡尔曼滤波器将预处理后的LiDAR特征点与IMU数据相融合,并使用后向传播来矫正雷达运动畸变,后端利用雷达相对位姿因子将LiDAR帧间配准结果作为约束因子与回环因子共同完成全局因子图优化。利用开源数据集和露天煤矿实地数据集验证了算法的鲁棒性和精确性。试验结果表明在城市结构化环境中文中所提算法与当前激光SLAM算法精度保持一致,而针对长达两千多米的露天煤矿实地环境,所提算法较FAST-LIO2、LIO-SAM紧耦合算法在定位精度上分别提高了46.00%和23.15%,且具有更高的鲁棒性。 展开更多
关键词 露天煤矿 同时定位与地图构建 激光雷达 惯性导航 因子图
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基于OGC规范和Open Source项目的WebGIS开发与应用 被引量:12
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作者 尹芳 冯敏 +1 位作者 刘磊 李锐 《计算机工程与应用》 CSCD 北大核心 2010年第30期68-70,74,共4页
为更好地实现地理空间信息共享,在最新开源(Open Source)项目基础上,设计与开发一个基于OGC标准规范的WebGIS空间数据管理系统,给出具体的实现步骤。该方案可高效地完成矢量空间信息的入库、地图发布、可视化浏览、空间目标对象属性信... 为更好地实现地理空间信息共享,在最新开源(Open Source)项目基础上,设计与开发一个基于OGC标准规范的WebGIS空间数据管理系统,给出具体的实现步骤。该方案可高效地完成矢量空间信息的入库、地图发布、可视化浏览、空间目标对象属性信息查询等任务,能够为集成应用提供标准的数据访问和获取接口。最后,将其应用到国家科技基础条件平台"地球系统科学数据共享平台"中,取得较好效果。 展开更多
关键词 开源(open Source)项目 OGC规范 WEBGIS 空间信息入库 地图发布 可视化浏览
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开源代码技术的FLASH地图实现方法——以MapServer+Ming为例 被引量:11
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作者 宋现锋 刘军志 +1 位作者 吴建国 谭海樵 《地球信息科学》 CSCD 2006年第4期101-105,共5页
本文详细地分析了MapServer地图服务器的体系结构,对MapServer+Ming生成Flash地图的方法进行了深入的探讨,并提出了相应的改进方法。最后使用开放源代码GIS软件搭建了一个Flash网络地图服务平台,利用丰富的地图数据VMAP0,验证上述系统... 本文详细地分析了MapServer地图服务器的体系结构,对MapServer+Ming生成Flash地图的方法进行了深入的探讨,并提出了相应的改进方法。最后使用开放源代码GIS软件搭建了一个Flash网络地图服务平台,利用丰富的地图数据VMAP0,验证上述系统原型。该方案的相关工作已经发布在美国明尼苏达大学的MapServer网站上。 展开更多
关键词 开源代码技术 Flash网络地图 mapSERVER
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基于开源的网络地图的实现技术——以MapServer和Ajax结合为例 被引量:3
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作者 于书媛 奚砚涛 +2 位作者 王一冒 牛坤 于雪涛 《测绘与空间地理信息》 2010年第6期48-51,共4页
基于网络发布地理信息数据主要是以网络地图服务的形式被广泛应用。开源WebGIS软件应用架构包括数据存储、分析处理应用和发布,对应的应用架构分为数据库技术、客户端软件和服务器端软件。本文通过建立开放式框架结构,结合客户端浏览器... 基于网络发布地理信息数据主要是以网络地图服务的形式被广泛应用。开源WebGIS软件应用架构包括数据存储、分析处理应用和发布,对应的应用架构分为数据库技术、客户端软件和服务器端软件。本文通过建立开放式框架结构,结合客户端浏览器、Ajax技术、PostgreSQL数据库以及PostGIS空间插件,尝试将客户端技术运用到GIS空间数据服务中,实现了基于Ajax技术的地图服务的应用。 展开更多
关键词 开源 网络地图服务 实现技术 mapSERVER Ajax技术 open Based Network Technology 客户端浏览器 应用架构 POSTGRESQL数据库 服务器端软件 地理信息数据 GIS空间数据 数据库技术 客户端软件 WebGIS软件 网络发布 数据存储
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基于Open API WebGIS的海洋渔业环境保障服务产品发布系统研究 被引量:1
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作者 蔡文博 滕骏华 +2 位作者 田杰 刘旭 刘建伟 《计算机应用与软件》 2017年第9期72-76,91,共6页
针对传统的预报图、短信无法满足渔民动态获取海洋预警报服务的需求,基于Open API设计了海洋渔业环境保障服务产品Web GIS发布系统。系统整体框架采用数据层、服务层、表现层、用户层的四层B/S结构,利用高德开放地图API和Java Script开... 针对传统的预报图、短信无法满足渔民动态获取海洋预警报服务的需求,基于Open API设计了海洋渔业环境保障服务产品Web GIS发布系统。系统整体框架采用数据层、服务层、表现层、用户层的四层B/S结构,利用高德开放地图API和Java Script开发语言实现了渔场海浪预报、渔场海面风预报和台风警报面向公众的发布功能。由于网络带宽的限制,系统通过一种计算坐标偏移量并映射为ASCII码的矢量数据压缩方法,较好地实现了渔场预报数据的Web传输。以某渔场海浪预报产品XML格式中间交换文件为例,数据压缩率达到38.5%。 展开更多
关键词 open API WEBGIS 地图API 海洋渔业 矢量数据压缩
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强传递的新特征
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作者 汪丹 张更容 《安徽大学学报(自然科学版)》 CAS 北大核心 2024年第1期28-34,共7页
动力系统是一门关于时间演化规律的数学学科,其中由紧致拓扑空间的连续自映射给出的动力系统的传递性一直以来都是动力系统研究的一个重要课题.令(X,f)是一个动力系统,对于X中任意的两个非空开子集U和V,若存在整数n≥0,使得U∩f-nV≠?,... 动力系统是一门关于时间演化规律的数学学科,其中由紧致拓扑空间的连续自映射给出的动力系统的传递性一直以来都是动力系统研究的一个重要课题.令(X,f)是一个动力系统,对于X中任意的两个非空开子集U和V,若存在整数n≥0,使得U∩f-nV≠?,则称(X,f)是拓扑传递的.运用N-开子集,定义几种新的拓扑传递的加强形式,研究并分别证明其多种等价命题,旨在开集的弱形式下得到一些动力学性质. 展开更多
关键词 强传递 N-开子集 强N-传递 N*-连续
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