基于OGC规范的多星多传感器卫星地面系统设计与实现

为解决传统卫星地面系统各业务功能单一、异构组织协作方面的不足, 提出了新型卫星地面系统的设计架构。以OGC(Open Geospatial Consortium)组织制定的空间信息服务标准为核心, 分别研究了卫星地面系统各业务系统的服务化, 给出了完整的新型卫星地面系统框架体系, 并进行了原型系统的开发和相关的应用实验。结果表明, 新型的卫星地面系统有助于实现多星多传感器的动态添加和跨组织协调合作。     

INTAMAP: The design and implementation of an interoperable automated interpolation web service

INTAMAP is a Web Processing Service for the automatic spatial interpolation of measured point data. Requirements were (i) using open standards for spatial data such as developed in the context of the Open Geospatial Consortium (OGC), (ii) using a suitable environment for statistical modelling and computation, and (iii) producing an integrated, open source solution. The system couples an open-source Web Processing Service (developed by 52°North), accepting data in the form of standardised XML documents (conforming to the OGC Observations and Measurements standard) with a computing back-end realised in the R statistical environment. The probability distribution of interpolation errors is encoded with UncertML, a markup language designed to encode uncertain data. Automatic interpolation needs to be useful for a wide range of applications and the algorithms have been designed to cope with anisotropy, extreme values, and data with known error distributions. Besides a fully automatic mode, the system can be used with different levels of user control over the interpolation process.     

A protocol for machine-readable cache policies in OGC web services: Application to the EuroGeoSource information system

An efficient access to the contents provided through OGC web services, widely used in environmental information systems, is usually achieved by means of caching strategies. Service-owners may be interested in expressing the conditions required to allow for this. If these conditions are expressed in a machine-readable way, automatic harvesters can be programmed to follow them.This paper proposes a protocol to specify and follow cache policies for OGC web services expressed in a machine-readable language. A preliminary implementation of this protocol has been tested in the EuroGeoSource project, where a number of Web Feature Services providing mineral deposits and energy resources are periodically cached to improve the efficiency and availability of several applications. The protocol addresses a nowadays common case, and can possibly be extended to allow for more detailed policies. Further work will help to determine how it could be integrated into a full Digital Rights Management system.     

面向森林生态学研究的Web处理服务系统

森林是陆地生态系统的主体,森林生态保护与恢复是生态文明建设的重要组成部分.面对森林生态模型单机化、重复开发部署的现状,本文设计并实现一个面向森林生态学研究的Web处理服务系统.该系统根据开放地理空间信息联盟（Open Geospatial Consortium,OGC）制定的空间数据共享及互操作的接口规范,基于WebService技术,实现了面向森林生态学研究的多模型整合,并将模型计算结果进行展示,减少了重复开发和部署工作,提高了数据与服务的共享性.     

Evaluation and Implementation of the OGC Web Processing Service for Use in Client-Side GIS

The Open Geospatial Consortium Web Processing Service specification is intended as a solution for creating and distributing web-based functions. This paper seeks to evaluate the WPS specification with respect to feasibility and utility, to identify areas for improvement, and to provide a demonstration implementation approach including a client-side tool and a server-side wrapping technique for exposing geoprocessing functionality through WPS using an asynchronous approach. Challenges with the WPS specification, some of which are already being addressed in the newest WPS revisions, are discussed together with proposed solutions. Several potential enhancements to the WPS proposal are introduced and considered, including a mechanism to guide client applications in prompting for correct data and a means to list the data available on a server.

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.     

基于SOA架构的WebGIS实现方法研究

处理功能的服务化已经成为当前空间信息领域的主要发展趋势之一。本文总结了当前空间信息服务开发存在的各种情况,并给出了相应的解决方案。根据本文的方法,可以很容易地将现有的常见GIS功能转化为网络处理服务,并对各种服务进行聚合,从而以一种标准的、与平台无关的形式提供并共享各种空间信息处理功能。     

基于OGC的中客户端WebGIS解决方案

万维网地理信息系统(WebGIS)已是当今GIS发展的一个热点,文章通过对现有WebGIS开发模型的研究,结合开放地理信息系统联合会(OGC)的WMS、WFS标准,探讨了基于OGC规范的中客户端模型的WebGIS的关键技术,并针对一些WebGIS的实际功能进行了具体实现。     

An OGC standard-oriented architecture for distributed coal mine map services

GIS- or CAD-based technology has been widely used for cartographic maps in coal mines, but structural gaps between such maps make it difficult to provide an integrated map service, for any specific purpose, at higher levels. There is no uniform platform that can be used to manage all involved maps. The main reason for this is that datasets are submitted by individual coal mines using their individual, diverse software. No consistent model is used within the software for data abstraction and symbolization. This paper first reviews all the essential specifications concerning OGC (Open Geospatial Consortium) interoperability. Then an OGC standard-oriented architecture is proposed to provide distributed coal mine map services. Within this new architecture the management of spatial data archives, and the integration of coal mine maps, are achieved through the interfaces of geospatial services. Finally an open source geospatial approach is suggested to implement the proposed scheme. A case study of the Huaibei Coal Group is used to demonstrate the proposal.     

基于集群技术的可伸缩云GIS服务平台研究

为了建立一个高可伸缩、能按需提供服务的云GIS服务平台,研究了云GIS服务平台的特征和需求。针对这些特征,利用可配置的服务器集群技术和分布式缓存技术,设计并实现了一个提供OGC标准服务的云GIS服务平台。通过实验验证了平台在处理高并发、计算密集型任务方面具有高可伸缩性和良好的加速比,并且在实际的GIS应用中验证了平台的可用性。