Design Considerations and Evaluation of a Collaborative, Spatio-Temporal Decision Support System

Collaborative spatial decision support systems (C‐SDSS) have been used to help groups of stakeholders understand data and search for opportunities at resolving local and regional decision problems in various domains including land use, trans‐ portation, and water resources. The key issue in designing an effective C‐SDSS is the anticipation of user information needs. Knowledge of user information needs can guide system designers in achieving a C‐SDSS that fits the decision process. In this paper we present a design approach that is informed by stakeholder concerns, as part of a user needs assessment. The approach is based on the premise that knowing stakeholders’ concerns can help anticipate user information needs and consequently lead to a more usable C‐SDSS. We demonstrate the approach with the example of a spatio‐temporal decision problem involving conjunctive water administration in the Boise River Basin in southwestern Idaho. The spatial dimension of the decision task involves delineating the areas of conjunctive water administration while the temporal dimension involves selecting the year in which a given area will start to be administered. We show how the elicitation of stakeholder concerns leads to functional specification of a collaborative spatio‐temporal decision support system.     

Spatial Data Infrastructure Requirements for Mobile Location Based Journey Planning

A growing number of services are now being offered over mobile devices. They typically combine positioning technology, wireless technology and spatial analysis methods applied to detailed geographical, time based data to offer services in support of time critical, spatial, mobile decision making. A collection of research issues need to be addressed in the successful delivery of such services that extend beyond issues of sophisticated network algorithms. Specifically, careful attention needs to be given to: (1) people and user environments; (2) access to networks; (3) policy, privacy and liability; (4) standards and interoperability; and (5) data quality. Spatial Data Infrastructure (SDI) is the collective term for these interconnected issues and has been a traditional area of research associated with geographic information science. In this paper the particular SDI requirements for the successful delivery of Location Based Services (LBS) are explored through the development of a prototype LBS for journey planning. The initial implementation and testing of this prototype has revealed that the SDI context is well suited as a framework within which to examine the related LBS issues. From a more technical perspective, the testing has revealed that data structure and the means by which large data sets are mined (in order to gather information to present to users) is critical to the success of timely information delivery over limited bandwidth media.     

基于B/S体系的Internet GIS分布式异构空间数据库的集成

Ｉｎｔｅｒｎｅｔ ＧＩＳ的蓬勃发展使得通过网络获取空间信息成为可能,然而,由于地理数据格式的多样性（异构数据）,限制了用户透明的获取远程数据以下对不同历史时期、不同格式、不同存在形式的数据用户端无缝的操作与表现。提出了Ｉｎｔｅｒｎｅｔ环境下基于浏览器／服务器结构交互的服务器端虚拟ＤＢＭＳ听概念,以对终端分布式异构数据库组织、管理,以及实现异构数据获取与互操作。     

An open-source web service for creating quadrilateral grids based on the rHEALPix Discrete Global Grid System

ABSTRACT

The foundation of modern Digital Earth frameworks is the Discrete Global Grid System (DGGS). To standardize the DGGS model, the Open Geospatial Consortium (OGC) recently created the DGGS Abstract Specification, which also aims to increase usability and interoperability between DGGSs. To support these demands and aid future research, open implementations are necessary. However, several OGC conformant DGGSs are not available for researchers to use. This has motivated us to develop an open-source web service that allows users to create quadrilateral grids based on the rHEALPix DGGS. In this paper, we describe the implementation of the web service, including issues and limitations, and demonstrate how discrete global grids and regional grids can be created. Lastly, we present examples that show how vector data sets can be modeled and integrated at different levels of resolution – a key benefit of the DGGS model.     

Location-based services: technical and business issues

Geographical Information System (GIS) and Global Positioning System (GPS) technologies are expanding their traditional applications to embrace a stream of consumer-focused, location-based applications. Through an integration with handheld devices capable of wireless communication and mobile computing, a wide range of what may be generically referred to as 'Location-Based Services' (LBS) may be offered to mobile users. A location-based service is able to provide targeted spatial information to mobile workers and consumers. These include utility location information, personal or asset tracking, concierge and route-guidance information, to name just a few of the possible LBS. The technologies and applications of LBS will play an ever increasingly important role in the modern, mobile, always-connected society. This paper endeavours to provide some background to the technology underlying location-based services, and to discuss some issues related to developing and launching LBS. These include whether wireless mobile technologies are ready to support LBS, which mobile positioning technologies can be used and what are their shortcomings, and how GIS developers manipulate spatial information to generate appropriate map images on mobile devices (such as cell phones and PDAs). In addition, the authors discuss such issues as interoperability, privacy protection and the market demand for LBS. Electronic Publication     

空间查询语言规范GML—QL的研究

广泛运用Web和分布式地理信息系统(WGIS/DGIS)有利于共享的空间数据库组织之间和用户通过互连网进行数据交换。不过,这些系统和应用软件的互操作性仍然是一个不能解决的问题,直到最近出版的地理标记语言(GML)标准的出现,这一问题才得到了解决。GML是一个新的实施规范并提供中立的框架为定义地理空间应用模式和对象的可扩展标记语言(XML)的文档。XML迅速成为一个事实上的标准电子数据交换之间的Web应用程序,然而,传统的数据库查询语言,在其目前的形式下并不适合直接查询和更新XML库。由W3C提出的XQuery查询语言为XML提供了强大的查询功能,但它缺乏支持空间查询,本文主要研究具有空间查询的语言GML-QL。     

空间决策支持系统开发平台及其应用实例

空间决策支持系统（Ｓｐａｔｉａｌ Ｄｅｃｉｓｉｏｎ Ｓｕｐｐｏｒｔ Ｓｙｓｔｅｍ ＳＤＳＳ）作为在地理信息系统（ＧＩＳ）和决策支持系统（ＤＳＳ）基础上发展起来的一个新光科学技术领域,自本世纪８０年代中后期后来,在国内外已引起越来越广泛的关注和重视。通过大量文献的分析表明：对这种系统目前尚有许多不同的理解和认识。作者认为只有那些能够帮助决策者生成、比较和选择空间决策方案的信息系统才能纳入ＳＤＳＳ的范     

网格环境下的三维空间数据互操作方法研究

探讨了一种在网格环境下的三维空间数据互操作方法 ,提出了基于SOAP(simpleobjectaccessprotocol)消息、以图层为单位的三维空间数据表达方法 ,通过解析SOAP消息便可得到符合GML规范的二维矢量数据、属性数据、纹理及模型数据 ,方便软件之间的数据交换和互操作。最后通过实验验证了该方法的可行性。     

西南资源环境空间信息网格研究

在空间信息科学领域,人们提出了空间信息网格(SIG)的概念,为空间数据的信息获取、共享、访问、分析和处理提供技术支持,以实现网格环境下的空间资源共享与协同。本文着重于网格技术与移动代理技术在地理信息共享领域的应用研究,结合空间信息网格技术,探讨了区域资源环境信息共享技术。在此基础上,本文设计了基于网格的地理信息共享与服务体系框架,并初步实现了基于该框架的西南地区资源环境信息共享与服务平台的原型系统。在原型系统中实现了网格环境下的WMS服务、WFS服务、服务资源注册服务、服务状态监测服务以及安全方面的访问控制服务。     

Providing scientific visualization for spatial data analysis: Criteria and an assessment of SAGE

A consistent theme in recent work on developing exploratory spatial data analysis (ESDA) has been the importance attached to visualization techniques, particularly following the pioneering development of packages such as SPIDER and REGARD (Haslett et al. 1990).  The focus on visual techniques is often justified in two ways: (a) the power of modern graphical interfaces means that graphics is no longer a way of simply presenting results in the form of maps or graphs, but a tool for the extraction of information from data; (b) graphical, exploratory methods are felt to be more intuitive for non-specialists to use than methods of numerical spatial statistics enabling wider participation in the process of getting data insights. However, little work has been done to decide which visualization tools might be needed to support ESDA, or how they can be most effectively implemented.  This paper briefly reviews a theoretical framework that has been suggested for addressing these issues, which comprises two elements: firstly a data model, based on the distinction between rough and smooth properties of spatial data, that defines what an analyst is looking for in data (Haining et al. 1998) and secondly a theoretical model for assessing the quality of visualisation tools (Cleveland 1994). The emphasis of this paper is the use of the theoretical framework to structure an assessment of SAGE, a software system that has been written for the spatial statistical analysis (including both exploratory and confirmatory data analysis) of area based data linked to a GIS. The aim of the assessment is to identify the desirable features of the system (that might be employed in other systems) whilst also highlighting what the additional requirements are thereby contributing to the development of systems for ESDA that contain good quality scientific visualization tools for exploratory spatial data analysis. Received: 30 September 1998/Accepted: 17 September 1999     

Putting meaning into NETMAR – the open service network for marine environmental data

The open service network for marine environmental data (NETMAR) project uses semantic web technologies in its pilot system which aims to allow users to search, download and integrate satellite, in situ and model data from open ocean and coastal areas. The semantic web is an extension of the fundamental ideas of the World Wide Web, building a web of data through annotation of metadata and data with hyperlinked resources. Within the framework of the NETMAR project, an interconnected semantic web resource was developed to aid in data and web service discovery and to validate Open Geospatial Consortium Web Processing Service orchestration. A second semantic resource was developed to support interoperability of coastal web atlases across jurisdictional boundaries. This paper outlines the approach taken to producing the resource registry used within the NETMAR project and demonstrates the use of these semantic resources to support user interactions with systems. Such interconnected semantic resources allow the increased ability to share and disseminate data through the facilitation of interoperability between data providers. The formal representation of geospatial knowledge to advance geospatial interoperability is a growing research area. Tools and methods such as those outlined in this paper have the potential to support these efforts.     

Semantic and syntactic interoperability in online processing of big Earth observation data

ABSTRACT

The challenge of enabling syntactic and semantic interoperability for comprehensive and reproducible online processing of big Earth observation (EO) data is still unsolved. Supporting both types of interoperability is one of the requirements to efficiently extract valuable information from the large amount of available multi-temporal gridded data sets. The proposed system wraps world models, (semantic interoperability) into OGC Web Processing Services (syntactic interoperability) for semantic online analyses. World models describe spatio-temporal entities and their relationships in a formal way. The proposed system serves as enabler for (1) technical interoperability using a standardised interface to be used by all types of clients and (2) allowing experts from different domains to develop complex analyses together as collaborative effort. Users are connecting the world models online to the data, which are maintained in a centralised storage as 3D spatio-temporal data cubes. It allows also non-experts to extract valuable information from EO data because data management, low-level interactions or specific software issues can be ignored. We discuss the concept of the proposed system, provide a technical implementation example and describe three use cases for extracting changes from EO images and demonstrate the usability also for non-EO, gridded, multi-temporal data sets (CORINE land cover).     

基于共享数据库平台的空间数据互操作实现方法

简要回顾了空间数据互操作实现的主要方法,分析了基于共享数据库平台的空间数据互操作的优势、实现困难以及实现的条件,以及不同GIS软件在数据模型上的差异。提出了两种基于共享数据库平台在不同客户端实现空间数据互操作的模式,在此基础上基于OracleSpatial,对基于共享数据库平台的互操作进行了实验,重点实验了有向点对象和注记对象在不同的客户端之间的互操作,展示了其可行性。     

WebGIS的空间数据共享与互操作

WebGIS技术是目前实现空间数据共享的有效手段，但是，由于空间数据异构复杂性，空间数据共享与互操作的实现还存在大量的问题亟待解决。本文阐述了空间数据共享与互操作技术模式，介绍了地理标记语言GML及在WebGIS中应用的优势，提出了一种基于GML的WebGIS空间数据共享与互操作方案。     

The development of spatial decision support system tool for marine spatial planning

A major problem associated with marine spatial planning (MSP) involves the difficult and time-consuming practice of creating a scenario that encompasses complex datasets in near real time via the use of a simple spatial analysis method. Moreover, decision-makers require a reliable, user-friendly system to quickly and accessibly acquire accurate spatial planning information. The development of national spatial data infrastructure (NSDI), which links the spatial data of a nation’s many diverse institutions, may pave the way for the development of a tool that can better utilize spatial datasets, such as a spatial decision support system (SDSS). Thus, this project aimed to develop an SDSS for MSP and to evaluate the feasibility of its integration within the NSDI framework. The seaweed culture was selected as an example due to its economic and technological acceptance by traditional fishers. Additionally, a multi-criteria analysis was used to develop the tool. Furthermore, a feasibility evaluation of its implementation within the NSDI framework was conducted based on the Delphi method. The results of the assessment indicated that the SDSS can be incorporated into the NSDI framework by addressing the policy issue – one map policy, updating custodians’ decree and data, and improve the standard and protocol.     

建立面向区域农业可持续发展的空间决策支持系统的方法探讨

在解决诸如工业选址的空间问题时，空间决策支持系统避免了流行的商用ＧＩＳ软件在空间信息的分析评价，时空分布，预测和模拟以及决策等模型分析功能的不足，该文提出了建立ＳＤＳＳ的两种基本途径；一是利用现有ＧＩＳ与分析决策模型进行集成联结生成ＳＤＳＳ；另一种途径是自行开发具有空间数据管理和分析决策模型的一体化ＳＤＳＳ。     

Testing Popular Visualization Techniques for Representing Model Uncertainty

Many land allocation issues, such as land-use planning, require input from extensive spatial databases and involve complex decision-making. Spatial decision support systems (SDSS) are designed to make these issues more transparent and to support the design and evaluation of land allocation alternatives. In this paper we analyze techniques for visualizing uncertainty of an urban growth model called SLEUTH, which is designed to aid decision-makers in the field of urban planning and fits into the computational framework of an SDSS. Two simple visualization techniques for portraying uncertainty—static comparison and toggling—are applied to SLEUTH results and rendered with different background information and color schemes. In order to evaluate the effectiveness of the two visualization techniques, a web-based survey was developed showing the visualizations along with questions about the usefulness of the two techniques. The web survey proved to be quickly accessible and easy to understand by the participants. Participants in the survey were mainly recruited among planners and decision-makers. They acknowledged the usefulness of portraying uncertainty for decision-making purposes. They slightly favored the static comparison technique over toggling. Both visualization techniques were applied to an urban growth case study for the greater Santa Barbara area in California, USA.     

空间决策支持系统及其支撑软件的设计与应用

本文讨论了SDSS的概念和基本理论,以决策支持为目标,面向半结构化和非结构化问题,用模型驱动的SDSS,是GIS未来的发展方向。在技术上用C语言实现了SDSS支撑软件的设计,并应用于国家科技攻关课题“三川河流域区域治理与开发信息系统”,取得了良好效果;同时对SDSS开发中存在问题作了讨论。     

Accounting for Spatial Uncertainty in Optimization with Spatial Decision Support Systems

Spatial decision support systems (SDSS) are designed to make complex resource allocation problems more transparent and to support the design and evaluation of allocation plans. Recent developments in this field focus on the design of allocation plans using optimization techniques. In this paper we analyze how uncertainty in spatial (input) data propagates through, and affects the results of, an optimization model. The optimization model calculates the optimal location for a ski run based on a slope map, which is derived from a digital elevation model (DEM). The uncertainty propagation is a generic method following a Monte Carlo approach, whereby realizations of the spatially correlated DEM error are generated using 'sequential Gaussian simulation'. We successfully applied the methodology to a case study in the Austrian Alps, showing the influence of spatial uncertainty on the optimal location of a ski run and the associated development costs. We also discuss the feasibility of routine incorporation of uncertainty propagation methodologies in an SDSS.