Combining the Arc Marine Framework with Geographic Metadata to Support Ocean Acoustic Modeling

A data model for use in a rapid environmental assessment system is constructed. The data model is used in an information layer that supports acoustic assessments of the ocean environment. Such an assessment requires use of both historic and real‐time oceanographic data. The foundation of the data model is Arc Marine, a framework specification for geospatial oceanographic databases that provides structures for containing the basic data types used in oceanographic research. Arc Marine also allows design extensions to account for application specific data structures as demonstrated through incorporation of aspects of the International Organization for Standardization (ISO) 19115 Geographic Information–Metadata standard. The ISO 19115 standard provides structures for recording the historic processing of the data sets. The data model is used to construct a database in the open source database management system (DBMS) PostgreSQL. The resulting system also incorporates the concept of user exits, the seamless extension of the DBMS through inclusion of application‐specific software.     

Enhancing Operations with Spatial Access Methods in a Database Management System for GIS

Much attention has been devoted in the past to support classes of applications which are not well served by conventional database systems. Focusing on the application domain of geographic information systems (GIS), several architectural approaches have been proposed to implement commercial or prototype systems and satisfy the urgent needs for geographic data handling. However, those systems suffer from several limitations because they either perform much processing on an application layer, which is at the top of the database management system (DBMS), or the underlying data models are not rich enough to represent the spatial dimension of geographic entities. This study examines the spatial operations that should be provided by a DBMS for the application domain of GIS and focuses on the various techniques which may be used to support the efficient execution of both simple operations and composite procedures that involve the spatial dimension of geographic entities.     

基于历史关系数据库的时空数据库实现研究

时空数据库是研究如何存储历史和当前的时空数据,从而跟踪分析某一区域的变化,最终实现时空模型化和模拟地学过程.采用历史关系数据库模式的时空数据库可以充分利用传统时态数据库时态查询功能和GIS空间分析处理功能这些方面成熟的研究成果和现有系统,降低时空数据库建立的费用和开销.分析了采用扩展关系型时空数据库的原因,介绍了历史关系数据库模式、时态关系代数和查询语言,研究了采用历史关系数据库模式在全关系化空间数据库中组织时态信息的方法,从而实现时空数据库.以麦地轮作为例说明了采用历史关系数据库模式建立时空数据库的可行性和有效性.     

对象关系数据库中的矢量数据集空间叠加方法

首先对当前空间数据模型的特点进行了评述,指出空间数据的存储方式与空间叠加方案的设计与实现密切相关,然后基于当前流行的对象关系数据模型,提出了将拓扑复合数据结构引入对象关系数据模型的空间叠加设计思想,并结合矢量数据空间叠加的流程和对象关系数据库的特点分析了实现该技术思想的关键技术问题,最后以PostgreSQL数据库管理系统为例,设计了可行的矢量数据集空间叠加方案。     

3-D Geovisualization of satellite images on smart devices by the integration of spatial DBMS,RESTful API and WebGL

Recent technological advancements in web-based geographic information systems have enabled access to satellite images on smart devices. The Representational State Transfer (REST) architecture overcomes difficulties that are associated with conventional data communications on the web, and the Web Graphics Library (WebGL) can be used as an alternative to web-based three-dimensional geographic visualization (3-D geovisualization) due to its efficient image processing capabilities. This paper describes a 3-D geovisualization system that was developed for satellite images on smart devices by integrating a spatial database management system (DBMS), a RESTful application programming interface (API), and WebGL. Spatiotemporal objects were constructed for time-series satellite images within a DBMS and a RESTful API was built for spatiotemporal queries to the time-series database so that the requested satellite data could be represented in 3-D on smart devices using WebGL. Satellite images that are represented in WebGL give a more realistic 3-D experience when they are combined with terrain data and provide for intuitive observations of the relationships between pixel values and associated geospatial conditions. This paper shows that a creative combination of existing technologies can be used to enhance and display satellite images on smart devices for 3-D geovisualization.     

基于ArcGIS Engine的SDE数据库版本管理及历史归档的研究与实现

版本（Version）是无重复存储的数据库副本,SDE版本管理能完成数据备份、长事务处理、模拟场景与方案等;历史归档（Archiving）是将空间数据库的所有变化都保存下来,记录其变化的时间和变化前后的状态。历史归档是能够实现无冗余历史数据备份,实现任意时刻数据的查看,以及某时间段内历史数据动态回放显示。本文以胶南市地理信息系统为实例,简单介绍SDE版本管理与历史归档的基本原理,阐述了数据库版本的创建、查看、协调、提交以及版本差异的实现方案,并结合长事务处理的应用,介绍了版本管理在数据编辑和数据更新中的应用,分析并指出了利用版本和历史归档实现历史数据回溯的优缺点,并展示了采用历史归档实现历史回溯的实现。     

The Performance of Vector Oriented Data Storage Strategies in ESRI's ArcGIS

The emergence of Geographical Information Systems (GIS) as an important tool in the analysis of spatial phenomena has been mirrored by the evolution of the data models underpinning such systems. When considering vector‐based solutions, such developments have seen a migration from single‐user, file‐based, topological hybrid models to multi‐user database management system (DBMS) based integrated formats, often with no inherent topology. With all these solutions still being readily available, the decision of which to employ for a given application is a complicated one. This study analyses the performance of a number of vector data storage formats for use with ESRI's ArcGIS, with the aim to facilitate the ‘intelligent selection’ of an appropriate solution. Such a solution will depend upon the application domain and both single‐user and multi‐user (corporate) scenarios are considered. Findings indicate that single‐user ESRI coverages and multi‐user ArSDE/Oracle strategies perform better when considering the range of GIS operations used to evaluate data store performance.     

基于NoSQL数据库的空间大数据分布式存储策略

基于关系型数据库的空间数据存储与处理是地理信息系统（geographic information system,GIS）领域的主流模式,但伴随着物联网、移动互联网、云计算及空间数据采集技术的发展,空间数据已从海量特征转变为大数据特征,对空间数据的存储和管理在数据量和处理模式上提出了新的挑战。首先分析了基于传统的集中式存储与管理模式在处理和应用大数据方面的局限性,包括存储对象的适应性、存储能力的可扩展性及高并发处理能力要求;然后在分析当前几大主流NoSQL数据库特点的基础上,指出了空间大数据基于NoSQL数据库的单一存储模式在数据操作方式、查询方式和数据高效管理方面存在的局限性;最后结合GIS领域空间大数据存储对数据库存储能力的可扩展性及数据处理和访问的高并发要求,提出基于内存数据库和NoSQL数据库的空间大数据分布式存储与综合处理策略,并开发了原型系统对提出的存储策略进行可行性和有效性进行了验证。     

地形图时空数据建库的两种方法及其对比

介绍了实际工作中经常遇到的地形图时空数据建库方法:保持现状式和数据追加式。分析对比了两种方法的优缺点:保持现状式实时维护了时空数据的现势性,方便现状数据的使用,但其数据库和表个数多,数据维护、历史数据恢复以及增量数据计算较复杂。数据追加式数据库个数少,数据维护、历史数据恢复以及增量数据计算较简单,但在使用现状数据时需做一定的数据查询、输出操作。作者建议使用后者,并将其中一个工作库固定为现状库,历史数据恢复时再建其他工作库以方便使用。     

基态修正的GIS数据库增量更新建模

为了对GIS数据库增量更新中的增量信息、版本数据库进行组织和管理,本文采用基态修正模型,将版本数据作为基态、版本数据对应的增量信息作为修正,分别设计了其存储的数据结构,并给出了基于该模型的增量更新流程。以1∶2000地形图数据的增量更新为例,开发了空间数据库增量更新原型系统,实现了多个增量信息文件的组织存储、快速集成到历史数据中,能够满足GIS数据库增量更新的需求。     

Ontology‐supported Querying of Geographical Databases

Querying geographical information systems has been recognized as a difficult task for non‐expert users. Furthermore, user queries are often characterized by semantic aspects not directly managed by traditional spatial databases or GIS. Examples of such semantic geospatial queries are the use of implicit spatial relations between objects, or the reference of domain concepts not explicitly represented in data. To handle such queries, we envisage a system that translates natural language queries into spatial SQL statements on a database, thus improving standard GIS with new semantic capabilities. Within this general objective, the contribution of this article is to introduce a methodology to handle semantic geospatial queries issued over a spatial database. This approach captures semantics from an ontology built upon the spatial database and enriched by domain concepts and properties specifically defined to represent the localization of objects. Some examples of the use of the methodology in the urban domain are presented.     

Geodatabase复制技术在国土资源管理中的应用

当前各地国土部门建立并投入使用的GIS数据库,大多采用独立、分散的数据库管理模式。该模式的缺陷在于:上下级数据库完全独立运行,无法实施有效的数据同步;导致数据库投入使用时间越长,上下级间的数据差异越大。传统的数据同步方式因功能限制而无法满足GIS数据同步的需求。Geodatabase双向复制能够在不同数据库平台多个地理数据库间实现数据双向同步,可以很好地解决上述问题。基于阳新县土地利用数据库建立分布式地理数据库,利用Geodatabase复制技术实现了同一数据库平台下多个地理数据库间的数据双向同步。     

小区沉降观测的探索

住宅小区建筑沉降观测主要采用的方法是:水准观测,闭合线路检核,根据观测周期和相邻位置构建沉降变形数据的时间和空间序列,用数据序列变化反映沉降过程.本文在分析小区沉降数据的特点重复性、相关性和延续性后,使用电子表格和数据库来管理沉降数据,其优势在于充分利用了传统关系数据库的成熟技术,如并发控制、事务处理、结构化查询、权限设置等.     

The geodetic requirements for commercial data base management systems

There are many data base management systems now available as commercially marketed software packages. Although most of these packages were initially aimed at bussiness or administrative data processing applications, they may frequently also be the right tool for a scientific data processing task. This becomes more apparent as we notice that scientific computer programmers are spending more and more time on data management requirements rather than the coding of mathematical algorithms. In a scientific environment, a generalized data base management package is best viewed as a tool for programmers, rather than as a tool for direct, independent use by end users or by agency management. To the end user, the most attractive feature of a commerical DBMS is usually the interactive retrieval and update language. To the programmer, the most attractive feature is more likely to be the strong support for various types of keyed access. All of the manipulations necessary to build and maintain indices and other tables can be treated as procedural abstractions. Coupled with a procedural language, a DBMS offers the programmer a higher level (in the sense of more abstract) language. The most important geodetic requirement on a commercial DBMS is therefore that the package contain a strong Data Manipulation Language, with strong support for the algorithmic language used for scientific processing. Presented at International Symposium on Management of Geodetic Data, Copenhagen, August 24–26, 1981.     

Weka‐STPM: a Software Architecture and Prototype for Semantic Trajectory Data Mining and Visualization

Enormous quantities of trajectory data are collected from many sources, such as GPS devices and mobile phones, as sequences of spatio‐temporal points. These data can be used in many application domains such as traffic management, urban planning, tourism, bird migration, and so on. Raw trajectory data, as generated by mobile devices have very little or no semantics, and in most applications a higher level of abstraction is needed to exploit these data for decision making. Although several different methods have been proposed so far for trajectory querying and mining, there are no software tools to help the end user with semantic trajectory data analysis. In this article we present a software architecture for semantic trajectory data mining as well as the first software prototype to enrich trajectory data with both semantic information and data mining. As a prototype we extend the Weka data mining toolkit with the module Weka‐STPM, which is interoperable with databases constructed under OGC specifications. We tested Weka‐STPM with real geographic databases, and trajectory data stored under the Postgresql/PostGIS DBMS.     

地籍信息系统中基于UML的关系数据库设计

讨论了在地籍信息系统(Cadastral Information System简称CIS)中如何应用统一建模语言(Un ified Model-ing Language简称UML)设计关系数据库(Relational Database简称RDB),并结合CIS中的属性数据,给出一个简单实例,为CIS的数据库设计提供一种参考。     

Representing Datum-level Uncertainty in Historical GIS

Geographic information systems have great potential as a tool for studying and teaching historical geography. However, using traditional GIS data models, even spatio-temporal forms, has been difficult due to the prevalence of uncertainty—both ambiguity and fuzziness—in source information concerning space, time, and theme. Explicitly uncertain assertions of a geo-historical datum can be modeled as an Evidentiary Set, a hybrid of a fuzzy set with probability and Dempster-Shafer evidence theory. This set formalism is designed to represent continuous and discrete value ambiguity (e.g., "about 10"), and fuzzy membership (e.g., "somewhat Central European"), including ambiguous membership and other fuzzy-ambiguous combinations. The formal set structure can be stored in GIS by representing continuous variation with a patch model, producing logical models for object-oriented and relational GIS databases. The relational implementation was tested in two GIS databases focused on human historical geography, showing the potential for the model to represent datum-level uncertainty in a wide variety of GIS applications.     

基于JSP、SVG技术的网上电子地图设计与实现

如何实现用户快速获取图形化地理信息,减少网络上的数据传输量是信息共享必须解决的问题之一。基于JSP、SVG和后台数据库的地理信息服务是一个崭新的研究领域。系统研究的主要内容是使用JSP、SVG技术,结合数据库技术,构建一个“网上电子地图应用系统”。系统采用SQLServer作为数据库和数据库管理系统;使用JSP技术访问数据库并动态生成SVG图形;实现了基于SVG的空间数据可视化;结合JavaScript技术实现电子地图的各个功能模块。     

GML for Representing Data from Spatio-Historical Databases: A Case Study

Many applications, in areas such as land use, traffic management and location aware services, involve the storage, analysis and sharing of spatio‐temporal data. The need to represent such data in a way that eases sharing across applications, has led to the development of the Geography Markup Language (GML), which provides a rich collection of constructs for representing spatial and associated aspatial data as XML documents. However, although there are a growing number of applications and tools that make use of GML, there are surprisingly few experience reports on the representation of data from existing applications or models using GML constructs. This paper provides one such report, describing the use of GML as an exchange format for the Tripod spatio‐historical database. This in turn involves identifying mappings between Tripod and GML constructs, and the development of a generic architecture for carrying out such mappings. The experience demonstrates that even though GML provides rich modelling facilities, the development of mappings from pre‐existing models can be challenging, as related constructs often provide semantically distinct capabilities.     

基于宗地变更的地籍时空数据库研究

地籍信息具有明显的时间特征,怎样有效地处理时间信息,以及如何将时间、空间及属性数据合理地组织在地籍信息系统的研究中具有重要意义。本文借鉴目前TG IS和各种应用模型的优势,提出一种基于宗地变更的时空数据库设计思想,针对地籍系统中地籍信息的历史查询和回溯的需求,将数据库分为现势库、历史库和变更库,弥补了有些时空数据库过于臃肿、或实体分类过于复杂从而影响系统运行效率等缺陷,以期对时态G IS在地籍信息系统中的研究有所帮助。