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1.
Service system planning has long been supported by location‐covering models designed to address access and accessibility issues. An important aspect of many systems is limits on service, often conceptualized as facility capacities. Much research can be found that proposes modeling approaches and solution techniques to account for capacitated covering problems, and commercial GIS software exists that is capable of structuring and applying facility service limits. This article reviews issues and challenges associated with the application of capacitated covering models, including critical evaluation of allocation approaches and GIS capabilities. Case studies involving service provision in two cities in California—San Jose and Santa Barbara—are provided to highlight associated issues faced in practice. While user‐friendly commercial software makes it easy to access capacitated cover models, there remain challenges for addressing underlying considerations and assumptions in practice.  相似文献   

2.
Advances in location modeling: GIS linkages and contributions   总被引:4,自引:1,他引:3  
Geographic information systems (GIS) have matured and proven to be an enabling technology, one that is important to many disciplines. Location analysis is also a field that has matured and continues to evolve. In fact, the combination of GIS and location science is at the forefront of advances in spatial analysis capabilities, offering substantial potential for continued and sustained theoretical and empirical evolution. This paper provides an overview of location analysis and discusses GIS. The paper highlights how GIS has contributed to location science in terms of data input, visualization, problem solution and theoretical advances. The significance of GIS in this context is that it is far more than a mere spatial data input mechanism, which is a commonly held misconception within geography, operations research and other allied disciplines. In contrast to other reviews, the focus in this paper is to highlight the theoretical foundations of location analysis and modeling and how GIS is contributing to important advancements in this field. An overall contribution of the paper is providing a perspective on spatial analysis and how associated specialty areas are evolving and thriving, particularly as a component of GIScience.  相似文献   

3.
This article reviews the interdisciplinary research field of spatial optimization for land acquisition problems. We start with a theoretical framework to identify three categories of spatial optimization models: problems with aspatial constraints, location models, and problems with topological constraints. Exact, heuristic, and metaheuristic approaches to solving these problems are critically discussed. Tools that are available in commercial and open‐source GIS packages are reviewed from four aspects. We first survey the off‐the‐shelf support and then the development environments in these packages. A case study of the one‐center problem is used to illustrate the computational performance of different solution methods. Finally the advantages and disadvantages of current GIS data models are discussed. The article concludes with challenges and future directions for solving spatial optimization problems for land acquisition.  相似文献   

4.
Abstract

Global challenges (such as economy and natural hazards) and technology advancements have triggered international leaders and organizations to rethink geosciences and Digital Earth in the new decade. The next generation visions pose grand challenges for infrastructure, especially computing infrastructure. The gradual establishment of cloud computing as a primary infrastructure provides new capabilities to meet the challenges. This paper reviews research conducted using cloud computing to address geoscience and Digital Earth needs within the context of an integrated Earth system. We also introduce the five papers selected through a rigorous review process as exemplar research in using cloud capabilities to address the challenges. The literature and research demonstrate that spatial cloud computing provides unprecedented new capabilities to enable Digital Earth and geosciences in the twenty-first century in several aspects: (1) virtually unlimited computing power for addressing big data storage, sharing, processing, and knowledge discovering challenges, (2) elastic, flexible, and easy-to-use computing infrastructure to facilitate the building of the next generation geospatial cyberinfrastructure, CyberGIS, CloudGIS, and Digital Earth, (3) seamless integration environment that enables mashing up observation, data, models, problems, and citizens, (4) research opportunities triggered by global challenges that may lead to breakthroughs in relevant fields including infrastructure building, GIScience, computer science, and geosciences, and (5) collaboration supported by cloud computing and across science domains, agencies, countries to collectively address global challenges from policy, management, system engineering, acquisition, and operation aspects.  相似文献   

5.
Semantic standardization is an integral part of sharing data for GIS and spatial analysis. It is part of a broader rubric of interoperability or the ability to share geographic information across multiple platforms and contexts. GIScience researchers have made considerable progress towards understanding and addressing the multiple challenges involved in achieving interoperability. For local government agencies interested in sharing spatial data, however, current interoperability approaches based on object-oriented data models represent idealistic solutions to problems of semantic heterogeneity that often exceed the level of sophistication and funding available. They are waiting for the market to decide how interoperability should be resolved. In order to assist in this transition, this paper presents a rule-based Visual Basic application to standardize the semantics of simple spatial entities using several classification systems. We use the example of well-log data, and argue that this approach enables agencies to share and structure data effectively in an interim period during which market and research standards for semantic interoperability are being determined. It contributes to a geospatial data infrastructure, while allowing agencies to share spatial data in a manner consistent with their level of expertise and existing data structures.  相似文献   

6.
A number of approaches for integrating GIS and qualitative research have emerged in recent years, as part of a resurgence of interest in mixed methods research in geography. These efforts to integrate qualitative data and qualitative analysis techniques complement a longstanding focus in GIScience upon ways of handling qualitative forms of spatial data and reasoning in digital environments, and extend engagements with 'the qualitative' in GIScience to include discussions of research methodologies. This article contributes to these emerging qualitative GIS methodologies by describing the structures and functions of 'computer-aided qualitative GIS' (CAQ-GIS), an approach for storing and analyzing qualitative, quantitative, and geovisual data in both GIS and computer aided data analysis software. CAQ-GIS uses modified structures from conventional desktop GIS to support storage of qualitative data and analytical codes, together with a parallel coding and analysis process carried out with GIS and a computer-aided data analysis software package. The inductive mixed methods analysis potential of CAQ-GIS is demonstrated with examples from research on children's urban geographies.  相似文献   

7.
Spatial analysis is an important area of research which continues to make major contributions to the exploratory capabilities of geographical information systems. The use and application of classic clustering methods is being pursued as an exploratory approach for the analysis of spatially referenced data. Numerous potential clustering approaches exist, so research assessing the relative differences of these approaches is important. This paper evaluates the median and central points optimization based clustering approaches for use in the context of exploratory spatial data analysis. Functional and visual comparisons using three spatial applications across a range of cluster values are carried out. The empirical results suggest that these two clustering approaches identify very similar groupings. The significance of this finding is that the development of clustering tools for exploratory analysis may be limited to the median based approach given relative computational and solvability considerations. Received: 28 September 1998/Accepted: 9 August 1999  相似文献   

8.
Neural Networks: A General Framework for Non-Linear Function Approximation   总被引:1,自引:0,他引:1  
The focus of this paper is on the neural network modelling approach that has gained increasing recognition in GIScience in recent years. The novelty about neural networks lies in their ability to model non‐linear processes with few, if any, a priori assumptions about the nature of the data‐generating process. The paper discusses some important issues that are central for successful application development. The scope is limited to feedforward neural networks, the leading example of neural networks. It is argued that failures in applications can usually be attributed to inadequate learning and/or inadequate complexity of the network model. Parameter estimation and a suitably chosen number of hidden units are, thus, of crucial importance for the success of real world neural network applications. The paper views network learning as an optimization problem, reviews two alternative approaches to network learning, and provides insights into current best practice to optimize complexity so to perform well on generalization tasks.  相似文献   

9.
This article reports on an empirical study of the trends and patterns of research activities in Geographic Information Science (GIScience) during the years 1997–2007. The GIScience research priorities identified by the University Consortium of Geographic Information Science (UCGIS) were used as guidelines to examine the 985 research articles published in six well‐recognized academic journals. Latent Semantic Analysis (LSA) was employed to investigate the association among the different GIScience research themes. The spatial and temporal patterns of the association between the publications and the different GIScience themes were examined to show the development of GIScience research during the study period. Furthermore, correlation analyses between the publications were conducted following the LSA results to reveal GIScience research networks, including the networks of the published articles and those formed by the research places. In this article, we applied an approach that was developed within information science to depict what GIS research activities were conducted when and where and how they connect to each other through sharing common research themes. The related findings pave the way for future efforts to describe the paradigm of GIScience as well as the pattern of GIScience research.  相似文献   

10.
互联网与大数据技术的高速发展为地理信息服务的互联共享与广泛应用提供了技术基础。面对资源海量、多源异构的地理信息服务,如何实现服务的有效组织并提供合理高效的服务组合,拓展地理信息服务的应用范围,满足更高层次的应用需求受到研究者的广泛关注。构建地理信息服务网络并通过语义实现服务协同,是一种可能的解决方案。本文分析了当前地理信息服务和地理信息服务网络研究的现状,依据服务网络领域的研究成果,从服务网络的表达和优化、服务协同的构建和优化两个方面探讨了基于网络构建的地理信息服务协同方法的发展潜力,进而提出了地理信息服务网络及协同面临的挑战与研究方向。  相似文献   

11.
Despite the fact that the field of GIScience has been around for two decades, there is still little agreement as to the exact contents and boundaries of the field. Many authors have dedicated several publications concerned with defining the field, yet little consensus has been reached. Because of the highly dynamic nature of the discipline, new areas are constantly added and rigid borders may have a constraining influence on the field. On the contrary, one agreed part of the many GIScience definitions is the search for general principles, but principles for what? Can we define one field or discipline or all potential fields using geospatial information? Probably not. Therefore, rather than attempting to demarcate exact boundaries for GIScience as a discipline or a multidisciplinary field in order to prove its respectability, we herein attempt to analyze the contents of such a dynamic field on the basis of scientific literature and to assess the multidisciplinary and multiparadigmatic nature of GIScience. Such a discussion is not purely of academic nature, but also bears implications beyond academic discourse, in terms of external scientific funding and research grants. We question whether there is a “dominant” paradigmatic approach in GIScience and identify a need for adopting a multiparadigmatic view to accommodate the multifaceted nature of space, spatial representations, and the societal implications of geospatial information.  相似文献   

12.
This editorial presents a special collection of papers addressing the concept of place and its use in geographical information science (GIScience). The concept of place is a topic of increasing interest among GIScience scholars. First attempts to formalise platial information have been made and it is increasingly held that user‐generated data sets in particular are often more platial than spatial in nature. At the same time, and especially when compared to geometric spatial concepts, the concept of place is ambiguous, complex and difficult to capture in formal and analytical terms, suggesting the need for interdisciplinary approaches. This collection presents articles covering a wide range of place‐related aspects, including both conceptual and more applied contributions. In the present editorial we summarise these and comment on their individual contributions, and hope that the readership of Transactions in GIS will find the special collection inspiring and informative.  相似文献   

13.
The amount of scientific literature on (Geographic) Object-based Image Analysis – GEOBIA has been and still is sharply increasing. These approaches to analysing imagery have antecedents in earlier research on image segmentation and use GIS-like spatial analysis within classification and feature extraction approaches. This article investigates these development and its implications and asks whether or not this is a new paradigm in remote sensing and Geographic Information Science (GIScience). We first discuss several limitations of prevailing per-pixel methods when applied to high resolution images. Then we explore the paradigm concept developed by Kuhn (1962) and discuss whether GEOBIA can be regarded as a paradigm according to this definition. We crystallize core concepts of GEOBIA, including the role of objects, of ontologies and the multiplicity of scales and we discuss how these conceptual developments support important methods in remote sensing such as change detection and accuracy assessment. The ramifications of the different theoretical foundations between the per-pixel paradigm and GEOBIA are analysed, as are some of the challenges along this path from pixels, to objects, to geo-intelligence. Based on several paradigm indications as defined by Kuhn and based on an analysis of peer-reviewed scientific literature we conclude that GEOBIA is a new and evolving paradigm.  相似文献   

14.
龚健雅  钟燕飞 《遥感学报》2016,20(5):733-747
随着对地观测技术的发展,海量遥感影像不断传输到地面。传统的遥感信息处理方法在处理效率、精度上的不足,限制了遥感信息的挖掘及利用,亟需发展智能化方法满足遥感影像处理的需求。受自然界中生物进化机制的启发,基于进化计算的遥感影像智能化处理方法具有以下特点:(1)拥有全局优化能力,对目标函数的优化能力更强;(2)具有自组织、自学习的特点,能够从遥感数据本身学习,不依赖数据分布等先验信息;(3)拥有处理多目标问题的能力,同时考虑多个目标函数而不需要人工确定它们之间的权重。因此,智能化遥感信息处理方法能够在海量遥感影像中有效地提取适用于不同应用目的的信息。本文主要介绍智能化遥感信息处理方法的典型应用包括遥感影像智能化分类(监督分类、聚类)、遥感影像亚像素信息提取(高光谱影像混合像元分解、亚像元制图),并讨论了遥感信息智能化处理方法的发展方向。  相似文献   

15.
土地利用优化配置是解决土地资源供需矛盾、协调社会经济发展与生态保护的重要技术手段,也是土地资源可持续利用需要解决的关键问题之一。随着空间模拟和智能优化技术的发展,土地利用优化的理论基础和方法体系也在不断更新。在文献计量的基础上,系统总结了国内外土地利用优化配置的驱动理论和方法,重点分析了空间模拟优化模型和智能寻优模型在土地利用优化配置建模应用中的进展和存在的问题,对土地利用优化配置未来的发展和面临的挑战进行了讨论和展望,提出自然与人文过程的耦合驱动、多模型的空间化协同、大数据知识挖掘方法的嵌入和数字孪生技术的支撑,应是土地利用优化配置领域下一阶段的研究方向。  相似文献   

16.
This paper presents a brief review of hyperspectral imagery and its analysis from a perspective based in Geographic Information Science. The ten original research priorities of the University Consortium for Geographic Information Science from 1996 and the five emerging themes from 2000/2001 are used as a framework to examine different aspects of management, analysis and use of hyperspectral imagery. A GIScience perspective identifies a series of issues that can develop the utility of hyperspectral imagery and gives an agenda for research that integrates hyperspectral imagery into Geographic Information Science to the benefit of both GIScience and hyperspectral remote sensing.  相似文献   

17.
The accreditation of GIS programs was first proposed more than 25 years ago as a means of encouraging consistency in instructional content and learning outcomes across many new GIS programs being developed at U.S. colleges and universities. However, in lieu of a peer review system to evaluate the quality of instruction, the GIS community focused instead on certification programs for recognizing and rewarding competency and professionalism among persons already in the workforce. With hundreds of colleges and universities now offering formal programs in GIScience ranging from certificates to undergraduate and graduate degrees, it may be an appropriate time reconsider rewards associated with accreditation. This article argues that accreditation can benefit institutions, students, and GIScience employers by directing attention to “upstream” and formative elements in the preparation of entry-level GIScience professionals that can potentially complement “downstream” and summative programs for recognizing experienced GIScience professionals such as certification. Along with providing detail about the implementation and administration of accreditation, we explore accreditation processes in surveying and engineering as possible pathways for accrediting academic GIScience programs.  相似文献   

18.
Knowledge-based spatial decision support systems (KBSDSS) incorporate heuristic reasoning, and analytical and spatial modelling capabilities to support decision making in resource and environmental management. They are able to provide the assistance for both the structuring and formulation of the spatial problem, and the design and execution of a solution process by automatically integrating different types of models and data. This paper presents a KBSDSS development environment, which connects a GIS tool (ARC/INFO) with an expert system tool (CLIPS) and a hypertext diagramming tool (HARDY). ARC/INFO provides capabilities for spatial data handling. CLIPS is used to develop knowledge bases and heuristic reasoning. HARDY is used to represent spatial problems in terms of diagrams that can then be translated into a CLIPS knowledge base for evaluation. The development environment allows users to structure their problems and develop models for particular requirements and domains.  相似文献   

19.
With the widespread availability of a large volume of urban data, stakeholders from different domains require advanced tools to manage, visualize and understand cities and their evolution. During the last few years, researchers have proposed numerous research works and applications to illustrate the cities of the past and possible scenarios of the future under different conditions. However, many of these approaches are one-time solutions and not based on standards, making them obsolete and unusable for reproducible research. In this article, we present UD-SV: an Urban data-Services and Visualization open-source framework for multidisciplinary research to handle complex processing, analysis, and visualization of urban data. However, our goal is not to present a one-time monolithic software solution for urban data management and analysis, but we demonstrate the design and development of an open and interoperable software framework driven by use cases from diverse users to solve applied research challenges. The main contribution of UD-SV is that it uses open standards and open data with documented and reproducible processes with a particular emphasis on the reuse of existing open-source software components. We also show an enhanced use of standards to enable a shift toward components that are interchangeable or composable with other existing components in the GIS community.  相似文献   

20.
从工程和生命科学的可靠性概念出发,结合地理信息科学的自身特点,强调空间数据及分析的全过程质量和分析结果的决策可用性。首次给出了可靠性空间分析的概念,分析了可靠性空间分析的特点、面临的主要问题和研究方法,探讨了可靠性空间分析的主要理论、研究方向和应用领域,促进了空间分析从不确定性研究向可靠性空间分析方向的发展。  相似文献   

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