共查询到20条相似文献，搜索用时 15 毫秒
1.
L. Grus J. Crompvoets A. K. Bregt 《International journal of geographical information science》2013,27(3):439-463
Many researchers throughout the world have been struggling to better understand and describe spatial data infrastructures (SDIs). Our knowledge of the real forces and mechanisms behind SDIs is still very limited. The reason for this difficulty might lie in the complex, dynamic and multifaceted nature of SDIs. To evaluate the functioning and effects of SDIs we must have a proper theory and understanding of their nature. This article describes a new approach to understanding SDIs by looking at them through the lens of complex adaptive systems (CASs). CASs are frequently described by the following features and behaviours: complexity, components, self-organization, openness, unpredictability, nonlinearity and adaptability, scale-independence, existence of feedback loop mechanism and sensitivity to initial conditions. In this article both CAS and SDI features are presented, examined and compared using three National SDI case studies from the Netherlands, Australia and Poland. These three National SDIs were carefully analysed to identify CAS features and behaviours. In addition, an Internet survey of SDI experts was carried out to gauge the degree to which they consider SDIs and CASs to be similar. This explorative study provides evidence that to a certain extent SDIs can be viewed as CASs because they have many features in common and behave in a similar way. Studying SDIs as CASs has significant implications for our understanding of SDIs. It will help us to identify and better understand the key factors and conditions for SDI functioning. Assuming that SDIs behave much like CASs, this also has implications for their assessment: assessment techniques typical for linear and predictable systems may not be valid for complex and adaptive systems. This implies that future studies on the development of an SDI assessment framework must consider the complex and adaptive nature of SDIs. 相似文献
2.
A. Rajabifard A. Binns I. Masser I. Williamson 《International journal of geographical information science》2013,27(7):727-741
A Spatial Data Infrastructure (SDI) facilitates and coordinates the exchange and sharing of spatial data between stakeholders in the spatial data community. With this objective in mind, countries throughout the world are developing SDIs to manage and utilize their spatial data assets more effectively. These countries are developing SDIs to assist in various kinds of decision‐making at different levels of government jurisdictions that have an important impact within their national boundaries. However, current research shows that SDI is understood and described differently by stakeholders from different disciplines and different jurisdictional levels. Therefore, in many cases, SDI initiatives remain very much an innovation, even among practitioners. There are still uncertainties regarding the benefits and identities of SDIs, particularly in connection with how they evolve over time to meet user needs. This paper reviews and assesses the development of SDIs throughout the world over the past 15 years and the leadership role of national governments in SDI creation. This assessment is based on the SDI activities of various jurisdictions including Asia‐Pacific, Australia, North America, and Europe, and research into the worldwide effects of spatial information clearing houses. This assessment includes a discussion on emerging trends in SDI development, with particular reference to the increasingly important role played by sub‐national governments and the private sector within the framework of SDI development. The paper concludes with a discussion of the implications for future SDI development, including the delivery of a virtual world that has a particular focus on facilitating decision‐making at a community level within a national context. 相似文献
3.
Jade Georis-Creuseveau Christophe Claramunt Françoise Gourmelon 《International journal of geographical information science》2017,31(1):122-138
The continuous development of Spatial Data Infrastructures (SDI) provides a favourable context for environmental management and planning. However, it appears that the actual contribution of SDIs should also depend on the correlation between users’ expectations and the services delivered to them. Several studies have addressed some organizational, methodological and technological aspects of the development of SDIs. However, only a few studies have, to the best of our knowledge, studied SDI use at large. This article introduces a methodological approach oriented towards the study of the relationship between SDIs and the users interacting with them as part of their professional practices. Our study is applied to coastal zone management and planning in France. This approach combines structural and data flow modelling. The former is based on Social Network Analysis (SNA) and the latter on Data Flow Diagrams (DFD). This modelling approach has been applied to an online questionnaire and semi-structured interviews. The results identify the SDIs, geographical data flows and institutional levels implied in French coastal zone management and planning. 相似文献
4.
Paul H.J. Hendriks Ezra Dessers Geert van Hootegem 《International journal of geographical information science》2013,27(8):1479-1494
The great interest in spatial data infrastructures (SDIs) has led to a wealth of SDI definitions in SDI debates. The article aims to contribute to both theory-oriented and practice-oriented SDI research by providing a critical re-examination of the SDI literature. Ashby's formal theory of regulation, which sees infrastructures as regulatory devices, is used to identify the strengths and weaknesses of several SDI definitions. This exercise shows how debates of the SDI objectives and the roles of users get caught in mantraps and also opens the door for a way out of this confusion by distinguishing between functional and adoption objectives. It also highlights the emphasis on technological components in the SDI definitions, which sidestep the importance of structural and human resource components in SDI. 相似文献
5.
Yu Zou Roger G. Ghanem 《International journal of geographical information science》2013,27(10):1917-1937
Despite its popularity, agent-based modeling is limited by serious barriers that constrain its usefulness as an exploratory tool. In particular, there is a paucity of systematic approaches for extracting coarse-grained, system-level information as it emerges in direct simulation. This is particularly problematic for agent-based models (ABMs) of complex urban systems in which macroscopic phenomena, such as sprawl, may manifest themselves coarsely from bottom-up dynamics among diverse agent-actors interacting across scales. Often these connections are not known, but treating them is nevertheless crucial in enabling prediction, in supporting decisions, and in facilitating the design, control, and optimization of urban systems. In this article, we describe and implement a metasimulation scheme for extracting macroscopic information from local dynamics of agent-based simulation, which allows acceleration of coarse-scale computing and which may also serve as a precursor to handle emergence in complex urban simulation. We compare direct ABM simulation, population-level equation solutions, and coarse projective integration. We apply the scheme to the simulation of urban sprawl from local drivers of urbanization, urban growth, and population dynamics. Numerical examples of the three approaches are provided to compare their accuracy and efficiency. We find that our metasimulation scheme can significantly accelerate complex urban simulations while maintaining faithful representation of the original model. 相似文献
6.
Joan Masó Xavier Pons Alaitz Zabala 《International journal of geographical information science》2013,27(6):983-1014
Spatial data infrastructure (SDI) actors have great expectations for the second-generation SDI currently under development. However, SDIs have many implementation problems at different levels that are delaying the development of the SDI framework. The aims of this article are to identify these difficulties, in the literature and based on our own experience, in order to determine how mature and useful the current SDI phenomena are. We can then determine whether a general reconceptualization is necessary or rather a set of technical improvements and good practices needs to be developed before the second-generation SDI is completed. This study is based on the following aspects: metadata about data and services, data models, data download, data and processing services, data portrayal and symbolization, and mass market aspects. This work aims to find an equilibrium between user-focused geoportals and web service interconnection (the user side vs. the server side). These deep reflections are motivated by a use case in the healthcare area in which we employed the Catalan regional SDI. The use case shows that even one of the best regional SDI implementations can fail to provide the required information and processes even when the required data exist. Several previous studies recognize the value of applying Web 2.0 and user participation approaches but few of these studies provide a real implementation. Another objective of this work is to show that it is easy to complement the classical, international standard-based SDI with a participative Web 2.0 approach. To do so, we present a mash-up portal built on top of the Catalan SDI catalogues. 相似文献
7.
An oases dynamics model and its application in the Manas oasis 总被引：2，自引：0，他引：2
This study applies theories of systems and system dynamics to ecological economic systems in the oasis environment, with the
intention of finding the basic characteristics of the oasis environment and its feedback structures. This study explores the
inner mechanisms of economic development in the oasis environment and its relationship to policy variables. This model is
applied to economic development in the Manas oasis of the Xinjiang Uygur Autonomous Region of China. System dynamics method
starts from studying feedback structure within the system study and then searches for the best solution through identifying
the right “policy point” and through model simulation in the computer. It embodies the cream of “systems cybernetics theory”.
This study is justified because the nature of the oasis system and the simulation results are scientifically sound and practically
feasible. 相似文献
8.
This study applies theories of systems and system dynamics to ecological economic systems in the oasis environment, with the intention of finding the basic characteristics of the oasis environment and its feedback structures. This study explores the inner mechanisms of economic development in the oasis environment and its relationship to policy variables. This model is applied to economic development in the Manas oasis of the Xinjiang Uygur Autonomous Region of China. System dynamics method starts from studying feedback structure within the system study and then searches for the best solution through identifying the right "policy point" and through model simulation in the computer. It embodies the cream of "systems cybernetics theory". This study is justified because the nature of the oasis system and the simulation results are scientifically sound and practically feasible. 相似文献
9.
Y. Georgiadou S. K. Puri 《International journal of geographical information science》2013,27(10):1113-1130
Recently, Spatial Data Infrastructures (SDIs) has been a rapidly expanding field and broadly assumed to underpin the development of information society and the knowledge economy. In this paper, we argue that the anticipated benefits of SDIs have largely not yet been generally realized in practice due to a lack of a robust theoretical framework as well as insufficient empirical research to guide the implementation efforts. We posit that learnings from the allied discipline of Information Infrastructures, which has matured during the 1990s in response to the proliferation of distributed, complex, and heterogeneous networked systems, can provide a useful theoretical lens to inform the emerging domain of SDIs. We focus on three key concepts identified in the domain of information infrastructure theory, viz. the installed base, reflexive standardization, and cultivation approach to design, to develop a theoretical framework, which is then applied to analyse the ongoing initiative to establish National Spatial Data Infrastructure (NSDI) in India. This analysis helps us to provide the basis to articulate a potential research agenda—for both theory and practice—which, we believe, offers the promise to better conceptualize and implement SDIs, particularly in developing country settings like India. 相似文献
10.
Michael R. Walls 《Natural Resources Research》1996,5(3):181-192
Petroleum exploration companies enter the twenty first century facing an increasingly competitive and risky environment. Under those circumstances, there is a growing need for better systematic decision-making that explicitly embodies the firm's desired goals and resource constraints. Computer-aided decision making, or decision support systems (DSS), provide an aid for those exploration management problems that are large, complex, unstructured, and involve management mudgment. Almost every present day DSS falls into one of two general classes. Vehicle DSSs such as linear/nonlinear programming models and other optimization routines, propose and impose specific methodologies to the decision-maker. On the other hand, toolbox DSSs, such as simulation programs, statistical functions, and graphical packages, are generally flexible in enabling their users to employ a variety of approaches and tools for their decision tasks but provide little guidance on both problem representation and investigation. This paper describes the development of a hybrid DSS model that combines the advantages of both the vehicle and toolbox systems components to provide a comprehensive approach to exploration planning from geological development through the capital allocation process. The Exploration Decision Support System (EDSS) preserves the flexibility of the toolbox system while enriching the problem-solving strategies available to the firm. The central objectives for developing an EDSS framework are: (1) better decisions about resource allocations; (2) more systematic understanding of the factors affecting exploration decisions; (3) improved communication about E&P performance objectives and constraints at all levels of decision-making; and (4) an explicit vehicle for continuous improvement of the petroleum exploration firm's decision-making process. The EDSS model can guide geological and exploration managers toward a more formal evaluation of projects, provide insight into the impact of competing choice alternatives, and significantly improve the quality of exploration decisions. 相似文献
11.
12.
武汉城市圈经济资源环境耦合的系统动力学模拟 总被引：4，自引：0，他引：4
都市圈经济资源环境系统通过相互作用形成了一个具多重反馈的耦合巨系统,三者间存在互相制约、相互作用的高阶、非线性复杂关系,传统的线性研究范式面临挑战。引入系统动力学理论,通过因果关系和流图分析方法,以武汉城市圈为例,建立经济-资源-环境耦合作用的系统动力学模型,结果显示:①模型具有很好的普适性,能真实反映系统要素之间相互耦合的动态演化过程,可以为调控经济资源环境系统协调发展提供决策参考;②借助模型可以对内部错综复杂、相互联系和相互耦合的巨系统进行动态多情景模拟,并揭示出协调发展模式下的经济快速增长为资源有效利用和环境保护治理提供更好的支持,三者相互促进,是武汉城市圈实现可持续发展的相对最佳方案。 相似文献
13.
基于多代理模型的城市土地利用博弈模拟 总被引：1，自引：1，他引：0
以美国达拉斯北部地区为例,通过建立基于多代理的人类系统和自然系统的耦合互动模型,研究不同土地管理策略的有效性.自然系统包含土地覆盖变化、流域水文动力学和野生动物栖息地生态系统.人类系统包括土地利益相关者(地主、屋主、开发商、政府)的影响土地利用变化价值观.系统强调自然对土地利用决策的反馈机制,不同类型代理相对空间位置的重要作用,以及同一类别中不同类型代理在特定情形下的相互转化.研究进行了两类模拟,一是模拟初始化的若干情景,包括不同类型地主和户主的分布、不同类型政府以及经济模型的假定;二是模拟主动式土地政策的实施效果.模拟结果表明,当政府购置保留地时考虑土地拥有者的价值观,较之单纯基于机会或生态因素更能导致有效的增长管理策略. 相似文献
14.
15.
Shaoying Li Zhifeng Wu Bin Ai Fang Wang 《International journal of geographical information science》2013,27(12):2410-2435
Spatial population dynamics affects resource allocation in urban planning. Simulation of population dynamics can provide useful information to urban planning for rapidly developing manufacturing metropolises. In such a metropolis with a concentration of immigrant labor forces, individual employment choices could have a significant effect on their residential decisions. There remains a need for an efficient method, which can simulate spatial population dynamics by considering the interactions between employment and residential choices. This article proposes an agent-based model for simulation of spatial population dynamics by addressing the influence of labor market on individual residential decisions. Labor economics theory is incorporated into a multi-agent system in this model. The long-term equilibrium process of labor market is established to define the interactions between labor supply and labor demand. An agent-based approach is adopted to simulate the economic behaviors and residential decisions of population individuals. The residential decisions of individuals would eventually have consequences on spatial population dynamics. The proposed model has been verified by the spatial dynamics simulation (2007 to 2010) of Dongguan, an emerging and renowned manufacturing metropolis in the Pearl River Delta, China. The results indicate that the simulated population size and spatial distribution of each town in Dongguan are close to those obtained from census data. The proposed model is also applied to predict spatial population dynamics based on two economic planning scenarios in Dongguan from 2010 to2015. The predicted results provide insights into the population dynamics of this fast-growing region. 相似文献
16.
京津冀地区人口规模调控政策参数化路径与系统模拟 总被引：1，自引：1，他引：0
政策调控是实现区域社会经济均衡发展的主要手段,采用系统分析方法评估和预测政策实施效果是进行决策的重要依据。然而,当前政策制定存在目标指向性不具体、调控力度不明确、协同作用机制不清晰等问题,既阻碍了政策的有效落实,更无法开展政策实施效果分析和决策优化。其根本症结在于缺少能够量化具体的政策目标并精确指导区域管理对策的政策参数。本文提出了面向系统动力学(System Dynamic, SD)模拟的区域调控政策参数化路径。通过细化政策指标、量化政策参数和区间化调控范围等方法,将政策调控转变为系统变量形式,代入到政策交互作用的系统动力学模型中,实现对政策调控效果的模拟。本文以区域人口规模调控政策为切入点,选择京津冀地区为案例区进行实证研究。结果显示,面向系统动力学模拟的政策参数化方案很好地重现了区域人口规模政策调控过程,能有效提高调控政策实施的精确性和可操作度,并为区域调控政策的配置和优化提供理论和方法的支撑。 相似文献
17.
基于“水—能源—食物—生态”纽带因果关系和贝叶斯网络的锡尔河流域用水分析 总被引：4，自引：1，他引：3
跨界流域水资源利用系统因受气候变化、人口增长、政治博弈、生态反馈等许多因素的互馈影响,包含复杂的“水—能源—食物—生态”纽带因果关系,形成具有高度不确定性的复杂非线性系统。传统水资源规划方法中缺少对这种复杂纽带关系的约束,而目前研究这类纽带关系多基于耦合多个模型、集成建模的方法,数据需求大、对复杂因果关系的不确定性模拟能力不足。而贝叶斯网络能以概率分布代替参数确定值来模拟系统中因果关系的不确定性、同时减少数据需求。本文利用贝叶斯概率网络,选取锡尔河流域为研究对象,量化这一因不合理用水而导致咸海生态危机的跨界内陆河流域“水—能源—食物—生态”纽带中的因果关系。结果表明贝叶斯网络能有效地模拟纽带中因果关系的强弱与不确定性,分析1970—2015年间不同时期影响咸海入湖水量的主要因素。为用水预测与流域水资源利用管理提供了系统性认知的基础,并展现出在较低模型复杂度和成本下建模的潜力。苏联时期,咸海入湖水量对农业开发增长的灌溉用水、上游水库建设的蓄水过程和径流量等较敏感;苏联解体后,咸海入湖水量对下游国家不合理使用的灌溉用水及上游水库蓄水量等节点高度敏感。短期内,需提高洗盐与灌溉用水效率,改良种植结构、增加粮食作物占比,并预防干旱危害;长期而言,通过普及先进滴灌技术,能大幅节约农业用水,在50%和80%的滴灌普及率下,新增咸海入湖水量将达到6.4 km 3和9.6 km 3以上,有望逐步缓解咸海生态危机。 相似文献
18.
基于细胞自动机与多主体系统理论的城市模拟原型模型 总被引：5，自引：5，他引：0
文章从城市地理学模拟模型研究发展相对滞后的现实出发,分析了传统城市模型模拟存在的问题与不足,讨论了计算机科学、复杂性研究、地理信息科学与技术、新发展的地学计算方法等作为计算城市模型发展基础的可行性,提出了一个基于细胞自动机与多主体系统理论与方法、包容了多尺度(宏观、中观、微观)层次的综合可计算城市模拟原型模型框架,对以邻里社区为基础的居住区位微观模拟模型作了概念上的讨论,分析了地学计算方法在城市模拟模型研究中的发展前沿。 相似文献
19.
基于agent的商业中心地空间结构动态模拟 总被引：1，自引：0，他引：1
以克里斯泰勒提出的中心地空间结构为研究对象,回顾和总结了中心地理论的主要内容、理论发展和实际应用,并以复杂性科学的理论和方法为基础,根据中心地理论假设,提出基于agent建模的两层次agent模型结构,通过遗传算法再现和验证了克氏单一职能的六边形中心地空间格局。模拟表明,微观自主体的相互作用的确可以突现出六边形宏观空间格局,这为以后突破克氏理论中"均质、静态、封闭"的不足提供了新的研究途径。中心地宏观空间结构的微观机理需要进一步结合经济学演绎模型和ABM的计算实验深入研究。 相似文献
20.
荒漠绿洲PRED系统特征与可持续发展定量研究 总被引：8，自引：4，他引：8
荒漠绿洲PRED系统是一个相当脆弱的系统，自然灾害频繁、水分失衡导致的生态风险大。在分析其特征的基础上，建立了衡量可持续发展的指标体系并运用层次分析法得出了这些因子对绿洲PRED系统可持续发展的权值，影响最大的前三位因子是：人均水资源量、绿洲化面积、人口素质、其权值分别为0.124、0.077、0.062。计算了河西走廊20个县（市、区）的SDI，排在最前面的依次是：萧北蒙古族自治县、嘉峪关市和玉门市、金川区，其SDI分别为0.437、0.406、0.405，排在最后面的依次是：古浪县、民勤县、天祝藏族自治县，其SDI分别为0.150、0.213、0.217。分析了这种格局产生的原因并提出了相应对策。 相似文献