基于OGC WPS标准的处理服务实现研究

Web Services为空间信息处理功能的互操作提供了一种通过网络访问的解决方案,但Web Services标准中缺少对空间信息元数据的定义.致力于GIS资源共享和处理互操作的Open Geospatial Consortium(OGC)组织,针对该问题制定了Web Processing Services(WPS)标准.基于WPS 3种主要方法提出了一种可扩展的WPS实现体系结构,用于解决空间信息互操作的问题.根据本体系结构,实现了一个镶嵌处理的demo WPS平台.试验证明,本体系结构具有很好的合理性、灵活性以及可扩展性,能够更好地解决处理功能互操作的问题.     

基于Web Services的空间信息服务开放互操作模型

分析了现有WebGIS系统中存在的缺陷，指出无法实现异构空间数据的共享与功能上的互操作是阻碍Web-GIs进一步发展的两大障碍.开放式的WebGIS是今后的发展方向，本文基于最新的Web技术提出一个七层结构的分布式空间信息服务开放互操作模型，为解决现有WebGIS中的问题，构建以分布式空间信息服务为核心的基础信息服务平台做了理论上的探讨与研究。     

基于GDAL开源库的流域地貌特征提取

GDAL是一个在X/MT许可协议下读写栅格、矢量空间数据的开源库,针对水文学上流域地貌特征提取研究中与栅格、矢量数据的频繁交互,引入GDAL地理空间开源库。分析GDAL模型库结构,空间数据打开、读写及转换等数据交互常用接口,在底层将上述接口与地貌参数提取算法无缝耦合。在.Net平台上,利用轻型SharpMap开源空间数据渲染控件作为显示窗体,开发独立地貌参数提取应用程序;在ArcGIS平台上通过ArcPy脚本语言包搭建地貌参数提取工具箱,通过图解建模工具可以将其中的工具与ArcGIS相关工具进行组合,构建一键地貌提取模型,为流域地貌特征的提取计算提供一条简便实用的技术路径。     

Design of a Java spatial extension for relational databases

Jaspa (Java Spatial) is a novel spatial extension for relational database management systems (RDBMSs). It is the result of a research project that aims to accomplish two goals: firstly, to fill the absence in the Free and Open Source Software (FOSS) world of a solid Java-based alternative to PostGIS, the leading spatial extension written in C. Secondly, to exploit the advantages of Java and the Java geospatial libraries over C in terms of portability and easiness to extend. Java programming for geospatial purposes is a flowering field and similar solutions to Jaspa have recently appeared, but none of them can equate with PostGIS due to lack of functionalities. Jaspa currently implements almost all PostGIS functionality. The next step will be the enrichment of the software with more sophisticated features: storage of spatial data in a topological structure within the RDBMS, cluster tolerance and geodetic functionalities. Jaspa is being developed at the Department of Cartographic Engineering, Geodesy and Photogrammetry of the Universidad Politécnica de Valencia and it has been published under an Open Source license on the OSOR.eu repository. This paper has been written by its creators with the aim of introducing users to its main capabilities.     

OWS性能监测评价方法研究及其原型系统实现——以OGC WMS为例

针对互联网上所共享发布的开放地理空间联盟网络服务（OWS）经常会出现不能访问或运行速度缓慢而导致难以利用的问题,为测试和评价这些地理信息服务的可用性和性能,通过研究OWS服务的固有特点,提出了实时监测OWS状态的动态规划模型和基于评价因子、评价权重等参数的评价模型,用以实现对OWS的监测与评价;基于上述模型与因子,设计开发了面向OWS的实时监测和性能评价原型系统,并以OGC网络地图服务（WMS）为例对模型与原型系统进行了实验验证。结果表明：该系统能够对相应的OWS进行实时监测与评价,所提的监测与评价方法与模型可为用户在众多的服务资源中获取其所感兴趣的数据提供参考信息,为地理信息服务使用者查找更优的服务资源提供帮助。     

基于REST面向资源的地理信息服务设计

结合具有表述性状态转移(REST)的Web服务与开放地理空间联盟(OGC)规范,设计一种面向资源的地理信息服务。将OGC规范作为服务接口标准,采用REST技术,以资源形式对外公开,从而实现信息共享和功能互操作。所有资源共享统一界面,在服务器与客户端之间进行状态传输。     

Use of ebRIM-based CSW with sensor observation services for registry and discovery of remote-sensing observations

Recent advances in Sensor Web geospatial data capture, such as high-resolution in satellite imagery and Web-ready data processing and modeling technologies, have led to the generation of large numbers of datasets from real-time or near real-time observations and measurements. Finding which sensor or data complies with criteria such as specific times, locations, and scales has become a bottleneck for Sensor Web-based applications, especially remote-sensing observations. In this paper, an architecture for use of the integration Sensor Observation Service (SOS) with the Open Geospatial Consortium (OGC) Catalogue Service-Web profile (CSW) is put forward. The architecture consists of a distributed geospatial sensor observation service, a geospatial catalogue service based on the ebXML Registry Information Model (ebRIM), SOS search and registry middleware, and a geospatial sensor portal. The SOS search and registry middleware finds the potential SOS, generating data granule information and inserting the records into CSW. The contents and sequence of the services, the available observations, and the metadata of the observations registry are described. A prototype system is designed and implemented using the service middleware technology and a standard interface and protocol. The feasibility and the response time of registry and retrieval of observations are evaluated using a realistic Earth Observing-1 (EO-1) SOS scenario. Extracting information from SOS requires the same execution time as record generation for CSW. The average data retrieval response time in SOS+CSW mode is 17.6% of that of the SOS-alone mode. The proposed architecture has the more advantages of SOS search and observation data retrieval than the existing sensor Web enabled systems.     

The effects of geography lessons with geospatial technologies on the development of high school students' relational thinking

Geospatial technologies offer access to geospatial information via digital representations, such as digital maps, and tools for interaction with those representations. The question is whether geography lessons with geospatial technologies really contribute to the development of students' geospatial thinking, in particular geospatial relational thinking, as is suggested in the literature about geospatial technologies in secondary education. This paper reports about the outcomes of a quasi-experimental research project, in which a geography lesson series with geospatial technologies was compared with a conventional geography lesson series that had the same content. Although the lesson series covered only three lessons, the data showed that the lesson series with geospatial technologies contributed significantly more to the development of students' geospatial relational thinking than the conventional lesson series. The effect size was ‘medium large’.     

Geospatial information infrastructures to address spatial needs in health: Collaboration,challenges and opportunities

Most health-related issues such as public health outbreaks and epidemiological threats are better understood from a spatial–temporal perspective and, clearly demand related geospatial datasets and services so that decision makers may jointly make informed decisions and coordinate response plans. Although current health applications support a kind of geospatial features, these are still disconnected from the wide range of geospatial services and datasets that geospatial information infrastructures may bring into health. In this paper we are questioning the hypothesis whether geospatial information infrastructures, in terms of standards-based geospatial services, technologies, and data models as operational assets already in place, can be exploited by health applications for which the geospatial dimension is of great importance. This may be certainly addressed by defining better collaboration strategies to uncover and promote geospatial assets to the health community. We discuss the value of collaboration, as well as the opportunities that geographic information infrastructures offer to address geospatial challenges in health applications.     

区块链技术在地学数据共享中的应用可行性分析

地学数据共享是地学研究的重要内容,也是挖掘地学数据、避免地学数据重复采集的重要途径,是现代数据密集型科研范式下地学研究的重要基础,因此,如何打破地学数据“孤岛”、实现不同地学数据便捷获取、保障数据安全、提升和扩展地学数据贡献者权益保护是地学数据共享中急需解决的问题。区块链技术的兴起,为地学数据价值外化途径扩充、提升数据安全和地学数据贡献者权益保护带来了新的可能。在系统梳理地学数据共享现状、存在问题、区块链基本原理、特点、底层架构以及应用现状的基础上,探讨区块链技术在地学数据共享中的应用可行性以及应用场景,阐述区块链技术在地学数据共享中的应用挑战,以期为地学数据共享领域区块链相关研究与应用提供参考。     

Application Feasibility Analysis of Block Chain Technology in Geospatial Data Sharing

Geospatial data sharing as a significant component of geoscience research. It is also an important means to exploit geoscience data and avoid repeated collection of geospatial data. It is an essential foundation for modern data-intensive geoscience research. Therefore, how to break the geospatial data “island” and realize different geoscience data portable access, secure data security, and promote geospatial data author copyright are urgent problems in geospatial data sharing. The rise of blockchain technology has brought new possibilities for the expansion of the value of geospatial data, the enhancement of data security and the improvement of the protection of the rights of stakeholders in geospatial data. Based on the systematic review of the status quo of data sharing, existing problems, basic principles of blockchain, underlying architecture, characteristics and application status, this paper discusses the application feasibility of blockchain technology in geospatial data sharing, and expounds the application challenges of blockchain technology in geospatial data sharing, in order to provide reference for the research and application of blockchain in geospatial data sharing.     

基于XML的地理信息元数据系统

首先对地理信息元数据的内容从不同角度进行了研究：地理信息元数据内容由描述数据自身的元数据信息和描述数据之间关系的元数据信息构成;根据地理信息元数据的规范程度对地理信息元数据进行分类,随规范程度递减分为标准元数据、共识元数据和用户元数据;同时还分析了利用XML来表示地理信息元数据方法．最后,设计了一个基于XML的地理信息元数据系统GeoMeta,对其体系结构和各个部分的功能进行了分析,并详细介绍了基于XML的地理信息元数据存储和查询策略．     

Agent-as-a-service-based geospatial service aggregation in the cloud: A case study of flood response

An Agent-as-a-Service (AaaS)-based geospatial service aggregation is proposed to build a more efficient, robust and intelligent geospatial service system in the Cloud for flood emergency response. It involves an AaaS infrastructure, encompassing the mechanisms and algorithms for geospatial Web Processing Service (WPS) generation, geoprocessing and aggregation. The method has the following advantages: 1) it allows separately hosted services and data to work together, avoiding transfers of large volumes of spatial data over the network; 2) it enriches geospatial service resources in the distributed environment by utilizing the agent cloning, migration and service regeneration capabilities of the AaaS, solving issues associated with lack of geospatial services to a certain extent; 3) it enables the migration of services to target nodes to finish a task, strengthening decentralization and enhancing the robustness of geospatial service aggregation; and 4) it helps domain experts and authorities solve interdisciplinary emergency issues using various Agent-generated geospatial services.     

空间信息融合与地理编码数据库的开发

空间信息的本质特征是区域空间上的分布性，可以根据行政区划、自然地理区域、坐标系统、地名、地址或数码(邮政编码、电活号码)来识别它们。该文阐述了地理编码数据库在空间信息融合和共享中的作用，提出利用地理编码技术，通过包含在空间信息中的地址定位要素来关联空间与非空间信息资源。最后，对地理编码数据库的体系结构和实现策略进行了探讨。     

Geospatial relation captioning for high-spatial-resolution images by using an attention-based neural network

High-spatial-resolution (HSR) remote sensing images serve as carriers of geographic information. Exploring geo-objects and their geospatial relations is fundamental in understanding HSR remote sensing images. To this end, this study proposes an intelligent semantic understanding method for HSR remote sensing images via geospatial relation captions. Firstly, we propose a method of geospatial relation expression to convey the topological, directional and distance relations of geo-objects in HSR images. Secondly, on the basis of images and their geospatial relation captions, an image dataset is constructed for model training. Finally, geospatial relation captioning is implemented for HSR images by using an attention-based deep neural network model. Experimental results demonstrate that the proposed captioning method can effectively provide geospatial semantics for HSR image understanding.     

"数字城市"地理空间数据框架建设研究

“数字城市”是城市信息化的重要组成部分,在国民经济和社会发展进程中发挥着重要作用。地理空间数据框架是构建“数字城市”的数据平台,是建设“数字城市”的必要保证。探讨了“数字城市”地理空间数据的组成和城市地理空间数据框架的构建,阐述了地理空间框架数据基准建设和地理空间数据库的建设,并以中国南方某典型城市为例介绍了“数字城市”地理空间数据框架的应用,指出了现阶段存在的问题并提出了相应的解决对策。     

区域地理空间数据整合技术研究

研究地理空间数据整合技术是实现在网络环境下地理空间数据的无缝集成与共享的关键技术问题。基于地理空间数据的多源异构性等特点,以ETL技术框架为基础,在数据仓库的整合机制下,设计符合地理空间数据整合要求的解决方案与技术流程,在数据整合过程每个阶段,都必须进行数据质量控制。文章最后以福建省自然资源基础数据库为例对其应用进行了探讨,为实践应用提供借鉴。     

中国岩石圈三维结构数据库元数据编辑器的开发

针对ArcCatalog空间数据管理的特点及开放的扩展机制,深入讨论了用户定制的元数据编辑器开发的步骤、主要技术等,这对今后地球空间元数据的深入研究和应用以及空间数据的规范化管理具有重要意义。