基于不同区域尺度的世界炼油能力分布特征与格局演化

本文基于全球、区域和国家三个不同尺度,对1965年～2011年世界炼油能力进行分析,得出结论：（1）整体而言,世界炼油能力呈现上升的趋势,且年际变化幅度在-3.14%～9.56%之间,1987年以来炼油能力的增长速度稳定,变化幅度在3%以内;（2）不同区域的炼油能力差异显著,其中亚太地区最高,北美和欧洲次之,非洲、中南美洲和中东地区炼油能力较低。各区域炼油能力变化的趋势和占世界炼油能力的比重呈现出不一样的变化特征;（3）从国家尺度来看,世界炼油能力的空间分布极不均衡,炼油能力超过百万桶/日的国家主要分布在北美、欧洲、中东和亚太地区。70年代以来世界炼油的重心呈现出不断东移的趋势,中东和亚太地区是世界炼油能力新的增长极。     

Measuring complexity in OGC web services XML schemas: pragmatic use and solutions

The use of standards in the geospatial domain, such as those defined by the Open Geospatial Consortium (OGC), for exchanging data has brought a great deal of interoperability upon which systems can be built in a reliable way. Unfortunately, these standards are becoming increasingly complex, making their implementation an arduous task. The use of appropriate software metrics can be very useful to quantify different properties of the standards that ultimately may suggest different solutions to deal with problems related to their complexity. In this regard, we present in this article an attempt to measure the complexity of the schemas associated with the OGC implementation specifications. We use a comprehensive set of metrics to provide a multidimensional view of this complexity. These metrics can be used to evaluate the impact of design decisions, study the evolution of schemas, and so on. We also present and evaluate different solutions that could be applied to overcome some of the problems associated with the complexity of the schemas.     

Semantic Web Services‐based process planning for earth science applications

In a Web service‐based distributed environment, individual services must be chained together dynamically to solve a complex real world problem. The Semantic Web Service has shown promise for automatic chaining of Web services. This paper addresses semi‐automatic geospatial service chaining through Semantic Web Services‐based process planning. Process planning includes three phases: process modeling, process model instantiation and workflow execution. Ontologies and Artificial Intelligence (AI) planning methods are employed in process planning to help a user dynamically create an executable workflow for earth science applications. In particular, the approach was implemented in a common data and service environment enabled by interoperable standards from OGC and W3C. A case study of the chaining process for wildfire prediction illustrates the applicability of this approach.     

Spatial inference with an interchangeable rule format

Rule interchange between information systems is expanding as new interoperable rule formats are emerging from research. However, existing spatial inference systems generally operate on locally stored data with an internal rule format. Consequently, their design offers little support or facilities for rule interchange. This article presents the requirements, components and design for a spatial inference system with rule interchange. Computational efficiency and overall functionality of the design are considered separately, with the latter demonstrated using encoded agricultural legislation and data. A spatial inference system with rule interchange is based on three primary components: rule representation, spatial functionality and data integration. Of these, the interoperable rule representation and data integration distinctly differ from existing spatial inference systems. The presented inference system combines a spatial superset of the W3C Rule Interchange Format (RIF) with full Open Geospatial Consortium simple feature access (OGC SFA) functionality and on-demand data integration utilising Resource Deception Framework (RDF). The design was found to be effective with a computational efficiency depending predominantly on the spatial operations. This design could be further adapted to implement spatial extensions for existing inference systems. Considerable benefits were also discovered when RIF was used as the native language for the inference engine, thereby removing the need for rule transformations and facilitating on-demand data integration with the GML.     

Microplastics in the marine environment

This review discusses the mechanisms of generation and potential impacts of microplastics in the ocean environment. Weathering degradation of plastics on the beaches results in their surface embrittlement and microcracking, yielding microparticles that are carried into water by wind or wave action. Unlike inorganic fines present in sea water, microplastics concentrate persistent organic pollutants (POPs) by partition. The relevant distribution coefficients for common POPs are several orders of magnitude in favour of the plastic medium. Consequently, the microparticles laden with high levels of POPs can be ingested by marine biota. Bioavailability and the efficiency of transfer of the ingested POPs across trophic levels are not known and the potential damage posed by these to the marine ecosystem has yet to be quantified and modelled. Given the increasing levels of plastic pollution of the oceans it is important to better understand the impact of microplastics in the ocean food web.     

City model enrichment

The combination of mobile communication technology with location and orientation aware digital cameras has introduced increasing interest in the exploitation of 3D city models for applications such as augmented reality and automated image captioning. The effectiveness of such applications is, at present, severely limited by the often poor quality of semantic annotation of the 3D models. In this paper, we show how freely available sources of georeferenced Web 2.0 information can be used for automated enrichment of 3D city models. Point referenced names of prominent buildings and landmarks mined from Wikipedia articles and from the OpenStreetMaps digital map and Geonames gazetteer have been matched to the 2D ground plan geometry of a 3D city model. In order to address the ambiguities that arise in the associations between these sources and the city model, we present procedures to merge potentially related buildings and implement fuzzy matching between reference points and building polygons. An experimental evaluation demonstrates the effectiveness of the presented methods.     

基于动态模式匹配的多版本网络要素服务统一访问方法

网络要素服务为不同格式GIS数据提供要素级的交互,对不同版本网络要素服务采纳了不同版本GML实现规范,不同版本实现规范的差异造成了不同版本的网络要素服务间还不能直接实现互操作.为了使一个WFS服务器对多个版本服务请求能够及时响应并得到该版本准确响应结果,本文采用一种多版本网络要素服务统一访问服务中间件方法,通过对模式文...     

海洋信息服务聚合平台应用研究

以当前海洋信息集成国内外的研究现状和存在的问题为背景;以海洋信息集成、业务整合的迫切需求,以及海洋地理信息系统的发展为驱动;以基于Mashup的信息聚合技术和Web服务技术为支持,提出了海洋信息服务聚合平台的体系框架。研究了面向聚合应用的海洋信息服务模式和基于Mashup的海洋信息服务的聚合方法。最后以海洋信息服务聚合平台为基础,以南海基础地理数据为背景数据．研究了基于聚合平俞的分布式海洋观测数据和海洋模型的集成方法。实验表明基于Mashup的海洋信息服务聚合方法可以轻松、快速地重组来自不同地方的数据服务和模型服务,能够满足海洋研究因情景而不断变化的需求。     

空间服务语义模式的地理信息服务发现

如何从大规模地理信息服务集合中快速且准确地发现目标服务是地理信息服务应用中的一个关键问题。当前基于关键字的服务发现方式缺乏语义支持,搜索效率低。本文在WSMO/WSML框架下,提出了一种基于空间服务语义模式的服务发现方法,将地理信息从语法模式转换为语义模式,明确表达空间数据中隐含的知识,有效克服数据源之间的语义异构。该方法能够显著提高地理信息服务发现的查全率和查准率。     

基于RIA地理信息共享平台的运维系统研究

运维系统是保证整个地理系统共享平台正常运行的重要组成部分,具有业务流程复杂,数据交互需求大等特点,由于基于B/S模式的传统Web应用程序在页面交互、数据可视化、传输效率等方面弱点制约其在运维系统中的应用,本文引入RIA技术有效解决上述问题。研究了RIA基本原理及应用可行性,并设计了基于该技术的Web应用程序结构模型。最后通过系统的实例运行,表明基于RIA的运维系统具有良好的性能。