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Measuring urban sprawl in Beijing with geo-spatial indices 被引量:14
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作者 JIANG Fang LIU Shenghe +1 位作者 YUAN Hong ZHANG Qing 《Journal of Geographical Sciences》 SCIE CSCD 2007年第4期469-478,共10页
Concerning about the rapid urban growth in recent China, this study takes Beijing as a case and puts forward that urban sprawl can be measured from spatial configuration, urban growth efficiency and external impacts, ... Concerning about the rapid urban growth in recent China, this study takes Beijing as a case and puts forward that urban sprawl can be measured from spatial configuration, urban growth efficiency and external impacts, and then develops a geo-spatial indices system for measuring sprawl, a total of 13 indicators. In order to calculate these indices, different sources data are selected, including land use maps, former land use planning, land price and floor-area-ratio samples, digitized map of the highways and city centers, population and GDP statistical data, etc. Various GIS spatial analysis methods are used to spatialize these indices into 100mx100m cells. Besides, an integrated urban sprawl index is calculated by weight sum of these 13 indices. The application result indicates that geo-spatial indices system can capture most of the typical features and interior differentia of urban sprawl. Construction land in Beijing has kept fast growing with large amount, low efficiency and disordered spatial configuration, indicating a typical sprawling tendency. The following specific sprawl features are identified by each indicator: (1) typical spatial configuration of sprawling: obvious fragmentation and irregularity of landscape due to unsuccessful enforcement of land use planning, unadvisable pattern of typical discontinuous development, strip development and leapfrog development; (2) low efficiency of sprawl: low development density, low population density and economic output in newly developed area; and (3) negative impacts on agriculture, environment and city life. According to the integrated sprawl index, the sprawling amount in the northern part is larger than that in the southern, but the sprawling extent is in converse case; most sprawling area include the marginal area of the near suburbs and the area between highways, etc. Four sprawling patterns are identified: randomly expansion at urban fringe, strip development along or between highways, scattered development of industrial land, leapfrog development of urban residence and industrial area. 展开更多
关键词 urban sprawl MEASUREMENT geo-spatial indices BEIJING
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Digital Watermark-based Security Technology for Geo-spatial Graphics Data 被引量:2
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作者 JIA Peihong CHEN Yunzhen +1 位作者 MA Jinsong ZHU Dakui 《Chinese Geographical Science》 SCIE CSCD 2006年第3期276-281,共6页
The paper presents a set of techniques of digital watermarking by which copyright and user rights messages are hidden into geo-spatial graphics data,as well as techniques of compressing and encrypting the watermarked ... The paper presents a set of techniques of digital watermarking by which copyright and user rights messages are hidden into geo-spatial graphics data,as well as techniques of compressing and encrypting the watermarked geo-spatial graphics data.The technology aims at tracing and resisting the illegal distribution and duplication of the geo-spatial graphics data product,so as to effectively protect the data producer's rights as well as to facilitate the secure sharing of geo-spatial graphics data.So far in the CIS field throughout the world,few researches have been made on digital watermarking.The research is a novel exploration both in the field of security management of geo-spatial graphics data and in the applications of digital watermarking technique.An application software employing the proposed technology has been developed.A number of experimental tests on the 1:500,000 digital bathymetric chart of the South China Sea and 1:10,000 digital topographic map of Jiangsu Province have been conducted to verify the feasibility of the proposed technology. 展开更多
关键词 geo-spatial graphics data copyright protection digital watermarking stego carrier data encrypting
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An Optimal Method for High-Resolution Population Geo-Spatial Data
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作者 Rami Sameer Ahmad Al Kloub 《Computers, Materials & Continua》 SCIE EI 2022年第11期2801-2820,共20页
China' Mainland has a poor distribution of meteorological stations.Existing models’estimation accuracy for creating high-resolution surfaces of meteorological data is restricted for air temperature,and low for re... China' Mainland has a poor distribution of meteorological stations.Existing models’estimation accuracy for creating high-resolution surfaces of meteorological data is restricted for air temperature,and low for relative humidity and wind speed(few studies reported).This study compared the typical generalized additive model(GAM)and autoencoder-based residual neural network(hereafter,residual network for short)in terms of predicting three meteorological parameters,namely air temperature,relative humidity,and wind speed,using data from 824 monitoring stations across China’s mainland in 2015.The performance of the two models was assessed using a 10-fold cross-validation procedure.The air temperature models employ basic variables such as latitude,longitude,elevation,and the day of the year.The relative humidity models employ air temperature and ozone concentration as covariates,while the wind speed models use wind speed coarse-resolution reanalysis data as covariates,in addition to the fundamental variables.Spatial coordinates represent spatial variation,while the time index of the day captures time variation in our spatiotemporal models.In comparison to GAM,the residual network considerably improved prediction accuracy:on average,the coefficient of variation(CV)R2 of the three meteorological parameters rose by 0.21,CV root-mean square(RMSE)fell by 37%,and the relative humidity model improved the most.The accuracy of relative humidity models was considerably improved once the monthly index was included,demonstrating that varied amounts of temporal variables are crucial for relative humidity models.We also spoke about the benefits and drawbacks of using coarse resolution reanalysis data and closest neighbor values as variables.In comparison to classic GAMs,this study indicates that the residual network model may considerably increase the accuracy of national high spatial(1 km)and temporal(daily)resolution meteorological data.Our findings have implications for high-resolution and high-accuracy meteorological parameter mapping in China. 展开更多
关键词 Machine learning remote sensing GEOGRAPHY disaster management geo-spatial analysis
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Geo-Spatial Information System for Developing Tourism Industry in Kandy District, Sri Lanka
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作者 T. M. S. P. K. Thennakoon H. M. G. D. Welagedara 《Chinese Business Review》 2017年第9期436-446,共11页
Tourism is a rapidly growing investment point in Sri Lanka, where huge investment is takeing place. Even though the investment is very massive, the planning, development, and marketing are key components of success in... Tourism is a rapidly growing investment point in Sri Lanka, where huge investment is takeing place. Even though the investment is very massive, the planning, development, and marketing are key components of success in tourism zone enhancement. The main objective of this study was to implement a geo-spatial information system for development of tourism in Kandy district. Primary data collection methods i.e. questionnaire survey, interviews, focus group interviews, and observations were employed for data collection. Google maps with Google API standards which are specially designed for developers and computer programmers were used for implementation of the system. System requirements were identified by interviewing tourists and observations made on tourist sites. Proximity analysis, spatial joint, and network analysis with Google direction application program interface (API) and Google place API were used to analyze data. The study highlights the potential tourist attractions and the accessibility and other required details through a web output. Issues and challenges faced by travelers are mainly lack of specific location information, public transport schedules, and reliable tourist attraction information. Online geo-spatial information system created in this study provides a guide for tourists to fred the destination routes, the service areas, and all necessary details on particular destinations. 展开更多
关键词 TOURISM geo-database API GIS geo-spatial Kandy
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Overcoming Object Misalignment in Geo-Spatial Datasets
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作者 Ismail Wadembere Patrick Ogao 《Journal of Geographic Information System》 2014年第4期307-316,共10页
In integrating geo-spatial datasets, sometimes layers are unable to perfectly overlay each other. In most cases, the cause of misalignment is the cartographic variation of objects forming features in the datasets. Eit... In integrating geo-spatial datasets, sometimes layers are unable to perfectly overlay each other. In most cases, the cause of misalignment is the cartographic variation of objects forming features in the datasets. Either this could be due to actual changes on ground, collection, or storage approaches used leading to overlapping or openings between features. In this paper, we present an alignment method that uses adjustment algorithms to update the geometry of features within a dataset or complementary adjacent datasets so that they can align to achieve perfect integration. The method identifies every unique spatial instance in datasets and their spatial points that define all their geometry;the differences are compared and used to compute the alignment parameters. This provides a uniform geo-spatial features’ alignment taking into consideration changes in the different datasets being integrated without affecting the topology and attributes. 展开更多
关键词 Object-Based GEOMETRY ALIGNMENT geo-spatial Management
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Coastline Security Engineering Using Geo-Spatial Approach: Case of Chabahar Port, Iran
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作者 Sharareh Pourebrahim Mehrdad Hadipour Mazlin Bin Mokhtar 《Journal of Geographic Information System》 2014年第3期236-245,共10页
Regarding the special potential of ports located on international coastlines such as Makoran Sea (Iran) for goods and human smuggling, national level of coastline security is very important. They can play a significan... Regarding the special potential of ports located on international coastlines such as Makoran Sea (Iran) for goods and human smuggling, national level of coastline security is very important. They can play a significant role in the development of power and security. Based on military reviews and analyses, police location and monitoring field view in the coastlines are strategic issues in modern security development. This research proposes a tool for development of coastal roads and coastal walking routes in the deployment of police. The main focuses are monitoring field view and accessibility to the strategic coastline. GIS tool plays an essential role in producing important security maps. Chabahar Port in Iran, as the most important port of Makoran Sea, has been selected as the study area, regarding its strategic role in the national economy and security. Research method focused on these major axes: successful establishment of police stations in shoreline for increasing monitoring and coastal security and suitable patrol of patrol police car in the coastal roads. This study adopts a scientific approach to the analysis of the present and future development in urban and security planning in coastal towns in the national and regional levels. 展开更多
关键词 SECURITY COASTLINE geo-spatial APPROACH
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Geo-spatial Information Science TOTAL CONTENTS(VOL.13 ISSUES 1-4,2010)
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《Geo-Spatial Information Science》 2010年第4期311-312,共2页
关键词 2010 VOL.13 ISSUES 1-4 2010 geo-spatial Information Science TOTAL CONTENTS TOTAL
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Geo-spatial Information Science TOTAL CONTENTS(Vol.9 lssues 1-4,2006)
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《Geo-Spatial Information Science》 2006年第4期311-312,共2页
关键词 TOTAL geo-spatial Information Science TOTAL CONTENTS Vol.9 lssues 1-4 2006
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Geo-spatial Information Science TOTALCONTENTS (Vol.8 lssues1-4,2005)
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《Geo-Spatial Information Science》 2005年第4期311-312,共2页
关键词 GIS geo-spatial Information Science TOTALCONTENTS Vol.8 lssues1-4 2005
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Dynamic Metadata Prefetching and Data Placement Algorithms for High-Performance Wide-Area Applications
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作者 Bing Wei Yubin Li +2 位作者 Yi Wu Ming Zhong Ning Luo 《Computers, Materials & Continua》 2025年第9期4773-4804,共32页
Metadata prefetching and data placement play a critical role in enhancing access performance for file systems operating over wide-area networks.However,developing effective strategies for metadata prefetching in envir... Metadata prefetching and data placement play a critical role in enhancing access performance for file systems operating over wide-area networks.However,developing effective strategies for metadata prefetching in environments with concurrent workloads and for data placement across distributed networks remains a significant challenge.This study introduces novel and efficient methodologies for metadata prefetching and data placement,leveraging fine-grained control of prefetching strategies and variable-sized data fragment writing to optimize the I/O bandwidth of distributed file systems.The proposed metadata prefetching technique employs dynamic workload analysis to identify dominant workload patterns and adaptively refines prefetching policies,thereby boosting metadata access efficiency under concurrent scenarios.Meanwhile,the data placement strategy improves write performance by storing data fragments locally within the nearest data center and transmitting only the fragment location metadata to the remote data center hosting the original file.Experimental evaluations using real-world system traces demonstrate that the proposed approaches reduce metadata access times by up to 33.5%and application data access times by 17.19%compared to state-of-the-art techniques. 展开更多
关键词 metadata prefetching data placement wide-area network file system(WANFS) concurrent workload optimization
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WebGIS中地理空间Metadata管理系统研究与设计 被引量:19
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作者 李琦 陈爱军 夏曙东 《中国图象图形学报(A辑)》 CSCD 2000年第10期811-817,共7页
为实现 Web GIS中地理空间信息的有效管理和网络共享 ,结合国际地理空间信息共享的标准规范 ,对Web GIS中地理空间 Metadata的定义、作用、内容、技术实现及其应用进行了详细的研究和设计 ,提出了与Web GIS集成的地理空间 Metadata管理... 为实现 Web GIS中地理空间信息的有效管理和网络共享 ,结合国际地理空间信息共享的标准规范 ,对Web GIS中地理空间 Metadata的定义、作用、内容、技术实现及其应用进行了详细的研究和设计 ,提出了与Web GIS集成的地理空间 Metadata管理系统解决方案 ,并给出了体现具体技术实现的原型系统 ,为国家空间信息基础设施和数字地球的建设提供了理论基础和技术原型 ,在当今信息化与数字地球时代 。 展开更多
关键词 WEBGIS 地理空间metadata 空间数据 管理系统
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数字地球建设中的地理空间Metadata研究 被引量:2
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作者 陈爱军 李琦 +1 位作者 徐光祐 史元春 《遥感学报》 EI CSCD 北大核心 2002年第4期313-319,共7页
为解决数字地球建设中现有海量地理空间信息的共建共享、有效管理和利用 ,结合国际地理空间Metadata标准规范 ,对数字地球建设中所需的地理空间Metadata的定义、作用、分类、内容、实现模型与实例及其应用进行详细研究和设计 ,提出用于... 为解决数字地球建设中现有海量地理空间信息的共建共享、有效管理和利用 ,结合国际地理空间Metadata标准规范 ,对数字地球建设中所需的地理空间Metadata的定义、作用、分类、内容、实现模型与实例及其应用进行详细研究和设计 ,提出用于数字地球建设的地理空间Metadata网络管理系统解决方案 ,并设计实现了原型系统 ,为数字地球建设中现有海量地理空间信息的有效管理和共建共享提供了理论基础和切实可行的技术支撑。对国家空间信息基础设施建设与数字地球建设具有重要的推动作用和深远的社会意义。 展开更多
关键词 数字地球 空间信息共享 地理空间数据 地理空间metadata GIS
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Metadata初探 被引量:7
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作者 李郎达 《情报科学》 CSSCI 北大核心 2001年第6期605-607,616,共4页
随着计算机技术与网络通信的进步 ,人类社会迈进了崭新的信息网络时代 ,电子图书馆相关计划普遍受到了各界的重视。而构建电子图书馆一个必要的步骤是将现有的馆藏、出版品经过电子化处理 ,并提供信息的检索、查询、浏览以及传递。在电... 随着计算机技术与网络通信的进步 ,人类社会迈进了崭新的信息网络时代 ,电子图书馆相关计划普遍受到了各界的重视。而构建电子图书馆一个必要的步骤是将现有的馆藏、出版品经过电子化处理 ,并提供信息的检索、查询、浏览以及传递。在电子化转换的过程中需要适合在网络环境中有效管理电子资源、并能呈现不同馆藏特色的资源描述格式。 Metadata,这个新的电子资源描述格式 (或称电子资源组织模式 ) ,已成为发展电子图书馆计划首要考虑的问题。本文将就 Metadata电子资源描述格式作简略的介绍。 展开更多
关键词 metadata 电子图书馆 机读目录 电子资源描述格式 Dblin CORE EAD
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Ontology and metadata for online learning resource repository management based on semantic web 被引量:3
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作者 宋华珠 钟珞 +1 位作者 王辉 李锐弢 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期399-403,共5页
An ontology and metadata for online learning resource repository management is constructed. First, based on the analysis of the use-case diagram, the upper ontology is illustrated which includes resource library ontol... An ontology and metadata for online learning resource repository management is constructed. First, based on the analysis of the use-case diagram, the upper ontology is illustrated which includes resource library ontology and user ontology, and evaluated from its function and implementation; then the corresponding class diagram, resource description framework (RDF) schema and extensible markup language (XML) schema are given. Secondly, the metadata for online learning resource repository management is proposed based on the Dublin Core Metadata Initiative and the IEEE Learning Technologies Standards Committee Learning Object Metadata Working Group. Finally, the inference instance is shown, which proves the validity of ontology and metadata in online learning resource repository management. 展开更多
关键词 semantic web online learning resource repository management(OLRRM) ONTOLOGY metadata
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Metadata:组织和发现Internet信息资源的数据 被引量:54
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作者 张智雄 《现代图书情报技术》 CSSCI 北大核心 1999年第1期21-25,共5页
metadata是“关于数据的数据”,本文介绍了metadata的基本情况,并对HTML和XML环境的 几个metadata规范进行了论述(包括 Dublin core,PICS,Web Collections,CDF,... metadata是“关于数据的数据”,本文介绍了metadata的基本情况,并对HTML和XML环境的 几个metadata规范进行了论述(包括 Dublin core,PICS,Web Collections,CDF,MCF及RDF)。由于metadata 在Internet信息资源的组织和发现方面起着非常重要的作用,作者呼吁国人应当加强对metadata的研究。 展开更多
关键词 metadata INTERNET 信息资源 数据
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Metadata与数字典藏 被引量:4
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作者 李郎达 《情报科学》 CSSCI 北大核心 2002年第12期1263-1265,1267,共4页
Metadata在数字资料的典藏中起着极其重要的作用。本文试图从数字典藏的策略及 Metadata对数字典藏的重要性 ,进一步探讨用于数字典藏的
关键词 数字资料 数字典藏 metadata 数字图书馆 数字信息资源
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数字人体空间数据的Metadata 被引量:4
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作者 毕思文 《中国医学影像技术》 CSCD 2003年第z1期140-145,共6页
笔者首先介绍了Metadata的发展背景和现状 ;然后研究了数字人体空间数据Metadata的理论基础、体系结构 ;最后阐述了数字人体空间数据Metadata的实现和今后研究的趋势。
关键词 数字人体 空间数据 metadata
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Information Description of Vegetable Planting Metadata Model 被引量:1
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作者 陈宏 赵健 +2 位作者 池美香 邱荣洲 翁启勇 《Agricultural Science & Technology》 CAS 2012年第1期238-241,共4页
[Objective] To study the information description of vegetable planting metadata model. [Method] On the basis of analyzing the data involved in every as- pect of vegetable planting, this paper put forward description s... [Objective] To study the information description of vegetable planting metadata model. [Method] On the basis of analyzing the data involved in every as- pect of vegetable planting, this paper put forward description schemes of vegetable planting metadata and constructed vegetable planting metadata model by the means of XML/XML schema. [Result] Metadata model of vegetable planting was established, and information description of vegetable planting metadata model was realized by the using of XML Schema. The whole metadata model consists of 7 first-class classifica- tions, including more than 800 information description points which could completely record vegetable planting-related information. [Conclusion] Standards for data collec- tion, management and sharing were provided for the agriculture applications in indus- tries like GAP management of vegetable planting, facility vegetable, food quality traceability, etc. 展开更多
关键词 Vegetable planting XML/XML Schema metadata
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基于Metadata crosswalks的青藏铁路元数据系统设计 被引量:2
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作者 冉有华 《遥感技术与应用》 CSCD 2004年第5期379-385,共7页
人们对数据的需求随着所要研究问题复杂程度的升高而变得复杂多样。青藏铁路地理信息系统数据库管理着不同来源、异质异构的海量数据,元数据在这样的大型系统中扮演着非常重要的角色。元数据分为两类,一类是地理空间元数据,用来描述青... 人们对数据的需求随着所要研究问题复杂程度的升高而变得复杂多样。青藏铁路地理信息系统数据库管理着不同来源、异质异构的海量数据,元数据在这样的大型系统中扮演着非常重要的角色。元数据分为两类,一类是地理空间元数据,用来描述青藏铁路沿线基础地理背景数据、地形数据、铁路工程数据、与空间相关的冻土和冻土工程地质数据,及数据库运行过程中产生的不同版本的空间数据等;一类是非地理空间元数据,包括属性数据和事务性数据,用来描述钻孔资料、项目研究论文、野外观测资料等。两类数据采用不同的元数据标准,需要引入Metadatacrosswalks技术以解决不同标准元数据间的集成访问,从而为数据用户提供统一高效的元数据检索服务。XML技术是实现这种机制的最佳选择。探讨了Metadatacrosswalks在青藏铁路地理信息元数据库系统中的适用性并对其进行了初步的设计。 展开更多
关键词 青藏铁路 metadata crosswalks ARCIMS
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Metadata:组织和发现Internet信息资源的数据 被引量:6
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作者 张智雄 《现代图书情报技术》 CSSCI 北大核心 1999年第S1期73-76,共4页
metadata是“关于数据的数据”,本文介绍了 m etadata的基本情况 ,并对 HTML 和 XML 环境的几个 m eta-data规范进行了论述 (包括 Dublin core,PICS,Web Collections,CDF ,MCF及 RDF)。由于 metadata在 Internet信息资源的组织和发现方... metadata是“关于数据的数据”,本文介绍了 m etadata的基本情况 ,并对 HTML 和 XML 环境的几个 m eta-data规范进行了论述 (包括 Dublin core,PICS,Web Collections,CDF ,MCF及 RDF)。由于 metadata在 Internet信息资源的组织和发现方面起着非常重要的作用 ,作者呼吁国人应当加强对 metadata的研究。 展开更多
关键词 metadata DUBLINCORE PICS CDF RDF
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