Version based spatial record management techniques for spatial database management system

The search operation of spatial data was a principal operation in existent spatial database management system, but the update operation of spatial data such as tracking are occurring frequently in the spatial database management system recently. So, necessity of concurrency improvement among transactions is increasing. In general database management system, many techniques have been studied to solve concurrency problem of transaction. Among them, multi-version algorithm does to minimize interference among transactions. However, to apply existent multi-version algorithm to improve concurrency of transaction to spatial database management system, the waste of storage happens because it must store entire version for spatial record even if only aspatial data of spatial record is changed. This paper has proposed the record management techniques to managese parating aspatial data version and spatial data version to decrease waste of storage for record version and improve concurrency among transactions.     

Version based spatial record management techniques for spatial database management system

The search operation of spatial data was a principal operation in existent spatial database management system, but the update operation of spatial data such as tracking are occurring frequently in the spatial database management system recently. So, necessity of concurrency improvement among transactions is increasing. In general database management system, many techniques have been studied to solve concurrency problem of transaction. Among them, multi-version algorithm does to minimize interference among transactions. However, to apply existent multi-version algorithm to improve concurrency of transaction to spatial database management system, the waste of storage happens because it must store entire version for spatial record even if only aspatial data of spatial record is changed. This paper has proposed the record management techniques to manage separating aspatial data version and spatial data version to decrease waste of storage for record version and improve concurrency among transactions.     

数字农业空间信息管理平台的设计与实现

根据数字农业空间信息管理平台的建设目标和要求,进行了空间数据库和属性数据库的设计与建设.在此基础上,采用SQL Server2000、ArcSDE、VB6.0和ArcEngine四者结合进行了平台总体架构和功能的设计,并进行了平台的开发,实现了平台与数据管理、地图基本操作、农业信息综合查询、农业空间分析、土地斑块调整、制图与输出系统等功能.     

油气藏开发管理GIS中空间数据库的设计及应用

油气田开发管理中具有大量的多系统、多层次的图形信息和属性信息，如何将这些地理数据组织成完整的空间数据库是GIS建立过程中相当重要的一项基础工作．针对油气藏开发管理中涉及的数据复杂多样的特殊性，介绍了如何建立油气藏开发管理空间数据库．并对在油气藏开发管理地理信息系统中，如何充分应用空间数据库来辅助油气藏开发管理做了简单说明。     

基于Petri网的兵团空间信息系统运行管理模型

Petri网由于具有图形化和数学化的双重特点,是系统业务过程建模、分析、优化、管理与集成的优秀技术,得到了广泛的应用.简要介绍Petri网,并对兵团空间信息系统进行了分析,然后利用Petri网建模技术来刻画兵团空间信息系统运行管理过程,通过构建管理模型来对系统实施有效的管理,以达到安全、可靠、方便地为兵团各类用户提供服...     

A solution for digital image management in spatial databases

Digital Orthographic Map (DOM) can be used in various applications because it contains both image features and terrain information. Spatial database management systems aim at the effective and efficient management of data related to a space,engineering design and so on. Thereby spatial database provides an efficient solution for managing DOM. According to large amounts of the DOM data in storage, a data compression based on wavelet is introduced into the storage. Another strategy to solve this problem is to decompose the raw image into tiles and store the tiles individually as separate tuples. The metadata of DOM can be used to organize and manage spatial information,especially for spatial data sharing and fast locating. A tool for browsing, zooming and querying the DOM data is also designed. We implemented these ideas in SISP (Spatial Information Sharing System) and applied the subsystem into the DOM management of Beijing City, which is an component of the Beijing Spatial Information Infrastructure.     

A solution for digital image management in spatial databases

Digital Orthographic Map (DOM) can be used in various applications because it contains both image features and terrain information. Spatial database management systems aim at the effective and efficient management of data related to a space, engineering design and so on. Thereby spatial database provides an efficient solution for managing DOM. According to large amounts of the DOM data in storage, a data compression based on wavelet is introduced into the storage. Another stratcgy to solve this problem is to decompose the raw image into tiles and store the tiles individually as separate tuples. The metadata of DOM can be used to organize and manage spatial information, especially for spatial data sharing and fast locating. A tool for browsing, zooming and querying the DOM data is also designed. We implemented these ideas in SISP (Spatial Information Sharing System) and applied the subsystem into the DOM management of Beiiing City, which is an component of the Beijing Spatial Information Infrastructure.     

A solutiong for digital image management in spatial databases

Digital Orthographic Map (DOM) can be used in various applications because it contains both image features and terrain information. Spatial database management systems aim at the effective and efficient management of data related to a space，engineering design and so on. Thereby spatial database provides an efficient solution for managing DOM. According to large amounts of the DOM data in storage，a data compression based on wavelet is introduced into the storage. Another strategy to solve this problem is to decompose the raw image into tiles and store the tiles individually as separate tuples. The metadata of DOM can be used to organize and manage spatial information， especially for spatial data sharing and fast locating. A tool for browsing， zooming and querying the DOM data is also designed. We implemented these ideas in SISP (Spatial Information Sharing System) and applied te subsystem into te DOM management of Beijing City，which is an component of the Beijing Spatial Information Infrastructure.     

基于AO空间参照系统的开发

针对非专业人员在地理信息软件中设定空间参照系统有一定的难度这一问题,利用AO高级组件开发技术,以我国目前常用的地图投影坐标系为例,提出在ArcMap下将AO组件开发技术和VBA有效结合,并实现了多个空间参照系统之间的转换.实验表明运用此程序可以更方便快捷的设定空间参照系统,减少操作人员难度,有一定的实用价值.     

A spatial entropy reflecting distribution of spatial objects

Decision trees are mainly used to classify data and predict data classes. A spatial decision tree has been designed using Euclidean distance between objects for reflecting spatial data characteristic. Even though this method explains the distance of objects in spatial dimension, it fails to represent distributions of spatial data and their relationships. But distributions of spatial data and relationships with their neighborhoods are very important in real world. This paper proposes decision tree based on spatial entropy that represents distributions of spatial data with dispersion and dissimilarity. The rate of dispersion by dissimilarity presents how related distribution of spatial data and nonspatial attributes. The experiment evaluates the accuracy and building time of decision tree as compared to previous methods and it shows that the proposed method makes efficient and scalable classification for spatial decision support.     

Spatial aggregations for spatial based decision 

For spatial based decision making such as choice of best place to construct a new department store, spatial data warehousing system is required more and more previous spatial data warehousing systems; however, provided decision making of nonspatial data on a map and so those cannot support enough spatial based decision making. The spatial aggregations are proposed for spatial based decision making in spatial data warehouses. The meaning of aggregation operators for applying spatial data was modified and new spatial aggregations were defined. These aggregations can support hierarchical concept of spatial measure. Using these aggregations, the spatial analysis classified by nonspatial data is provided. In case study, how to use these aggregations and how to support spatial based decision making are shown.     

A spatial entropy reflecting distribution of spatial objects

Decision trees are mainly used to classify data and predict data classes. A spatial decision tree has been designed using Euclidean distance between objects for reflecting spatial data characteristic. Even though this method explains the distance of objects in spatial dimension, it fails to represent distributions of spatial data and their relationships. But distributions of spatial data and relationships with their neighborhoods are very important in real world. This paper proposes decision tree based on spatial entropy that represents distributions of spatial data with dispersion and dissimilarity. The rate of dispersion by dissimilarity presents how related distribution of spatial data and non-spatial attributes. The experiment evaluates the accuracy and building time of decision tree as compared to previous methods and it shows that the proposed method makes efficient and scalable classification for spatial decision support.     

Spatial aggregations for spatial based decision making in spatial data warehouses

For spatial based decision making such as choice of best place to construct a new department store, spatial data warehousing system is required more and more previous spatial data warehousing systems; however, provided decision making of non-spatial data on a map and so those cannot support enough spatial based decision making. The spatial aggregations are proposed for spatial based decision making in spatial data warehouses. The meaning of aggregation operators for applying spatial data was modified and new spatial aggregations were defined. These aggregations can support hierarchical concept of spatial measure. Using these aggregations, the spatial analysis classified by non-spatial data is provided. In case study, how to use these aggregations and how to support spatial based decision making are shown.     

组件式GIS开发中的空间数据管理方式探讨

组件式地理信息系统有三种对空间数据的管理和访问方式,取决于GIS系统的规模和应用需求.MapObjects是一个功能强大的地理信息系统组件,它支持多种数据访问方法.在基于该组件的校园地下管线地理信息系统开发中,将图形数据和属性数据在管理方式上进行分割,扩展了组件式GIS的数据库访问机制,对建立灵活的小型地理信息系统具有一定的通用性.     

A Voronoi-based spatial algebra for spatial relations

Spatial relation between spatial objects is a very important topic for spatial reasoning, query and analysis in geographical information systems (GIS). The most popular models in current use have fundamental deficiencies in theory. In this paper, a generic algebra for spatial relations is presented, in which (i) appropriate operators from set operators (i.e. union, intersection, difference, difference by, symmetric difference, etc.) are utilized to distinguish the spatial relations between neighboring spatial objects; (ii) three types of values are used for the computational results of set operations-content, dimension and number of connected components; and (iii) a spatial object is treated as a whole but the Voronoi region of an object is employed to enhance its interaction with its neighbours. This algebra overcomes the shortcomings of the existing models and it can effectively describe the relations of spatial objects.     

有效支持空间OLAP的空间数据仓库模型研究

为了实现各类空间联机分析,提供更加全面灵活的空间决策支持,提出了一个空间数据立方体与空间索引结构相互协作的空间数据仓库模型,并同时构建了一个与之协作的空间索引结构aR^ B_tree．aR^ B_tree基于R^ _tree和B_tree实现,存储了空间维及时间维的聚集信息和层次关系,可以有效支持区域聚集查询．对各种空间联机分析操作进行了分类,分析表明该模型充分利用了传统数据仓库成熟的建模和联机分析技术,结合了空间索引结构在空间层次结构上的灵活特性,可以有效地支持各类空间联机分析．最后比较了aR^ B_tree与其他索引结构在区域聚集查询方面的性能．实验结果证明,在区域聚集查询中aR^ B_tree的节点访问次数和查询执行时间均小于现有索引结构．     

空间数据集成研究--以空间数据仓库的构建为例

随着空间数据复杂性的增加,现有的空间数据库和空间分析工具已经不能提供足够的决策支持,迫切需要建立大量具有历史数据,以及不同尺度的空间数据仓库．在建设空间数据仓库的过程中,数据集成是一个重要的环节,专门针对空问数据的集成更是一项艰巨的工作,本文在研究了现有的空间数据库,空间数据仓库以及空间数据集成的基础上,首先探讨了空间数据仓库模型的建立过程,然后系统提出了面向空间数据仓库数据模型的数据集成的两个主要的方面：不同数据源的空间数据的集成;不同尺度维上的空间数据的集成.     

空间分解技术在电磁散射中的应用

采用基于电场积分方程的空间分解技术,求解目标的单、双站雷达散射截面。该方法首先将散射体划分为若干子区域,然后步进迭代每个子区域的电流,最终精确重构整个目标的雷达散射特性;为了改善数值精度和计算速度,有效地克服内谐振现象,采用"双向重叠区域"设置和"物理光学中心前向迭代"等一些策略;数值方法表明,同传统矩量法相比,空间分解技术的使用,有效避免了内谐振的产生,加速了阻抗矩阵的求逆。     

A solution of spatial query processing and query optimization for spatial databases

Recently, attention has been focused on spatial query language which is used to query spatial databases. A design of spatial query language has been presented in this paper by extending the standard relational database query language SQL. It recognizes the significantly different requirements of spatial data handling and overcomes the inherent problems of the application of conventional database query languages. This design is based on an extended spatial data model, including the spatial data types and the spatial operators on them. The processing and optimization of spatial queries have also been discussed in this design. In the end, an implementation of this design is given in a spatial query subsystem.     

A solution of spatial query processing and query optimization for spatial databases

Recently,attention has been focused on spatial query language which is used to query spatial databases. A design of spatial query language has been presented in this paper by extending the standard relational database query language SQL. It recognizes the significantly different requirements of spatial data handling and overcomes the inherent problems of the application of conventional database query languages. This design is based on an extended spatial data model,including the spatial data types and the spatial operators on them. The processing and optimization of spatial queries have also been discussed in this design. In the end,an implementation of this design is given in a spatial query subsystem.