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1.
Environmental modelling often requires a long iterative process of sourcing, reformatting, analyzing, and introducing various types of data into the model. Much of the data to be analyzed are geospatial data—digital terrain models (DTM), river basin boundaries, snow cover from satellite imagery, etc.—and so the modelling workflow typically involves the use of multiple desktop GIS and remote sensing software packages, with limited compatibility among them. Recent advances in service-oriented architectures (SOA) are allowing users to migrate from dedicated desktop solutions to on-line, loosely coupled, and standards-based services which accept source data, process them, and pass results as basic parameters to other intermediate services and/or then to the main model, which also may be made available on-line. This contribution presents a service-oriented application that addresses the issues of data accessibility and service interoperability for environmental models. Key model capabilities are implemented as geospatial services, which are combined to form complex services, and may be reused in other similar contexts. This work was carried out under the auspices of the AWARE project funded by the European programme Global Monitoring for Environment and Security (GMES). We show results of the service-oriented application applied to alpine runoff models, including the use of geospatial services facilitating discovery, access, processing and visualization of geospatial data in a distributed manner.  相似文献   

2.
Geospatial datasets of forest characteristics are modeled representations of real populations on the ground. The continuous spatial character of such datasets provides an incredible source of information at the landscape level for ecosystem research, policy analysis, and planning applications, all of which are critical for addressing current challenges related to climate change, urbanization pressures, and data requirements for monitoring carbon sequestration. However, the effectiveness of these applications is dependent upon the accuracy of the geospatial input datasets. A comprehensive set of robust measures is necessary to provide sufficient information to effectively assess the accuracy of these modeled geospatial datasets being produced. Yet challenges in the availability of reference data, in the appropriateness of assessment methods to dataset use, and in the completeness of assessment methods available have continued to hamper the timely and consistent application of map assessments. In this study we present a suite of assessments that can be used to characterize the accuracy of geospatial datasets of modeled continuous variables—an increasingly common format for modeling such attributes as proportion or probability of forestland as well as more traditionally continuous attributes such as leaf area index and forest biomass. It is a comparative accuracy assessment, in which each modeled dataset is compared to a set of reference data, recognizing both the potential for error in reference data, and probable differences in spatial support between the datasets. When used together, this proposed suite of assessments provides essential information on the type, magnitude, frequency and location of errors in each dataset. The assessments presented depend upon reference data with large sample sizes. The U.S. Forest Service (USFS) Forest Inventory and Analysis (FIA) database is introduced as an available reference dataset of sufficient sampling intensity to take full advantage of these assessments and facilitate their prompt application after modeled datasets are developed. We illustrate the application of this suite of assessments with two modeled datasets of forest biomass, in Minnesota and New York. The information provided by this suite of assessments substantially improves a user's ability to apply modeled geospatial datasets effectively and to assess the relative strengths and weaknesses of multiple datasets depicting the same forest characteristic.  相似文献   

3.
In the world of geospatial data infrastructures, geoportals are developed to facilitate access and use of geospatial resources, including data. The design and implementation of effective and efficient geoportals are becoming crucial. Providing possibilities for users to organize and integrate available resources can arguably enhance the process of data discovery and spatial analysis required, and hence, is the focus of this paper. We argue that the synthesis of summaries of distributed datasets, map and feature services through the geoportal can present a coherent view to support data discovery. For this purpose, the atlas metaphor is used as an indexing server and integration interface of summaries. Thematic maps and a storyteller view are accessible through the atlas metaphor. They can be used to provide a supporting context for data discovery and access purposes.
Trias AdityaEmail:
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4.
The notion of environment is receiving an increasing attention in the development of multiagent applications. This is witnessed by the emergence of a number of infrastructures providing agent designers with useful means to develop the agent environment, and thus to structure an effective multiagent application. In this paper we analyse the role and features of such infrastructures, and survey some relevant examples. We endorse a general viewpoint where the environment of a multiagent system is seen as a set of basic bricks we call environment abstractions, which (i) provide agents with services useful for achieving individual and social goals, and (ii) are supported by some underlying software infrastructure managing their creation and exploitation. Accordingly, we focus the survey on the opportunities that environment infrastructures provide to system designers when developing multiagent applications.  相似文献   

5.
In the context of homeland security, critical infrastructures are "those physical and information technology facilities, networks, services and assets which, if disrupted or destroyed, would have a serious impact on the health, safety, security, or economic well-being of citizens or the effective functioning of governments." Transportation infrastructures are a key component of a nation's critical infrastructures, covering physical assets such as airports, ports, and railway and mass transit networks as well as software systems such as traffic control systems. In effect, among various critical infrastructures spanning a range of economic sectors and government operations, transportation is widely viewed as one of the most significant and impactful. A 2002 study concerning the significance of infrastructure components and the consequences of a destructive event rated transportation as "extremely significant." Other components at this highest level of significance were communications, power, emergency response personnel and assets, and national security resources.  相似文献   

6.
WebGIS中地理空间Metadata管理系统研究与设计   总被引:12,自引:0,他引:12       下载免费PDF全文
为实现WebGIS中地理空间信息的有效管理和网络共享,结合国际地理空间信息共享的标准规范,对WebGIS中地理空间Metadata的定义、作用、内容、技术实现及其应用进行了详细的研究和设计,提出了与与WebGIS集成的地理空间Metadata管理系统解决方案,并给出了体现具体技术实现的原型系统,为国家空间信息基础设施和数字地球的建设提供了理论基础和技术原型,在当今信息化与数字地球时代,对地理空间信  相似文献   

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9.
空间信息融合与地理编码数据库的开发   总被引:2,自引:0,他引:2  
江洲  李琦  王凌云 《计算机工程》2004,30(5):1-2,153
空间信息的本质特征是区域空间上的分布性,可以根据行政区划、自然地理区域、坐标系统、地名、地址或数码(邮政编码、电活号码)来识别它们。该文阐述了地理编码数据库在空间信息融合和共享中的作用,提出利用地理编码技术,通过包含在空间信息中的地址定位要素来关联空间与非空间信息资源。最后,对地理编码数据库的体系结构和实现策略进行了探讨。  相似文献   

10.
In recent years, spatial data infrastructures (SDIs) have gained great popularity as a solution to facilitate interoperable access to geospatial data offered by different agencies. In order to enhance the data retrieval process, current infrastructures usually offer a catalog service. Nevertheless, such catalog services still have important limitations that make it difficult for users to find the geospatial data that they are interested in. Some current catalog drawbacks include the use of a single record to describe all the feature types offered by a service, the lack of formal means to describe the semantics of the underlying data, and the lack of an effective ranking metric to organize the results retrieved from a query. Aiming to overcome these limitations, this article proposes SESDI (Semantically-Enabled Spatial Data Infrastructures), which is framework that reuses techniques of classic information retrieval to improve geographic data retrieval in a SDI. Moreover, the framework proposes several ranking metrics to solve spatial, semantic, temporal and multidimensional queries.  相似文献   

11.
基于SOA的空间信息资源整合与服务模式探讨   总被引:1,自引:0,他引:1  
提高空间信息资源的整合与服务水平,在迈向信息和服务型社会的过程中具有十分重要的意义。文章根据作者近年来在该领域的相关应用研究,对空间信息资源整合与服务模式进行了探讨,总结了基于SOA实现空间信息资源整合与服务的模式,并通过实例阐述了空间信息资源整合与服务的组织、实施和应用。  相似文献   

12.
Sharing geospatial provenance in a service-oriented environment   总被引:1,自引:0,他引:1  
One of the earliest investigations of provenance was inspired by applications in GIS in the early 1990’s. Provenance records the processing history of a data product. It provides an information context to help users determine the reliability of data products. Conventional provenance applications in GIS focus on provenance capture, representation, and usage in a stand-alone environment such as a desktop-based GIS software system. They cannot support wide sharing and open access of provenance in a distributed environment. The growth of service-oriented sharing and processing of geospatial data brings some new challenges in provenance-aware applications. One is how to share geospatial provenance in an interoperable way. This paper describes the development of provenance service for geospatial data products using the ebXML Registry Information Model (ebRIM) of a geospatial catalog service, which follows the interface specifications of the OGC Catalogue Services for the Web (CSW). This approach fits well the current service stack of the GIS domain and facilitates the management of geospatial data provenance in an open and distributed environment.  相似文献   

13.
移动位置服务(LBS)是一个分布式多方参与的系统,给移动商业应用带来了一个快速发展的时机,但由于其拥有访问私人信息的权利,以至于也给它们的用户隐私带来很大的风险.为此,通过对能够有效保护用户隐私的模型进行了研究,提出了一个体系结构和一个协议,协议中使用一个位置中间件把来自LBS供应商提供的用户关心的区域信息和来自移动运营商的用户位置信息进行匹配.结果表明,该协议使得隐私友好的服务成为可能,而且仍然是高效率.  相似文献   

14.
Semantic E-Workflow Composition   总被引:39,自引:0,他引:39  
Systems and infrastructures are currently being developed to support Web services. The main idea is to encapsulate an organization's functionality within an appropriate interface and advertise it as Web services. While in some cases Web services may be utilized in an isolated form, it is normal to expect Web services to be integrated as part of workflow processes. The composition of workflow processes that model e-service applications differs from the design of traditional workflows, in terms of the number of tasks (Web services) available to the composition process, in their heterogeneity, and in their autonomy. Therefore, two problems need to be solved: how to efficiently discover Web services—based on functional and operational requirements—and how to facilitate the interoperability of heterogeneous Web services. In this paper, we present a solution within the context of the emerging Semantic Web that includes use of ontologies to overcome some of the problem. We describe a prototype that has been implemented to illustrate how discovery and interoperability functions are achieved more efficiently.  相似文献   

15.
This paper investigates the case of shipments of containers with avocados from farmers in Africa to grocery store shelves in the European Union. We find 3 predominant challenges to containerized shipping that effectively become trade barriers: international trade cost, lead time uncertainty, and security risks. We use activity theory to describe, understand, and analyze the shipping activity in the international trade ecosystem with focus on physical objects and their related information. We find that the shipment becomes problematic and can be characterized as a runaway object in the heterogeneous and multiple organizational setting of international trade. Our analysis of shipping reveals (1) inefficient collaboration across loosely coupled activity systems and (2) fragmented information infrastructures. We propose the solution of Shipping Information Pipeline, a shared information infrastructure, thus facilitating collaboration in containerized shipping and contributing to lowering trade barriers. Shipping Information Pipeline can significantly improve containerized shipping resulting in estimated potential benefits of up to 4.7% growth in global GDP.  相似文献   

16.
Many geographic analyses are very time-consuming and do not scale well when large datasets are involved. For example, the interpolation of DEMs (digital evaluation model) for large geographic areas could become a problem in practical application, especially for web applications such as terrain visualization, where a fast response is required and computational demands exceed the capacity of a traditional single processing unit conducting serial processing. Therefore, high performance and parallel computing approaches, such as grid computing, were investigated to speed up the geographic analysis algorithms, such as DEM interpolation. The key for grid computing is to configure an optimized grid computing platform for the geospatial analysis and optimally schedule the geospatial tasks within a grid platform. However, there is no research focused on this. Using DEM interoperation as an example, we report our systematic research on configuring and scheduling a high performance grid computing platform to improve the performance of geographic analyses through a systematic study on how the number of cores, processors, grid nodes, different network connections and concurrent request impact the speedup of geospatial analyses. Condor, a grid middleware, is used to schedule the DEM interpolation tasks for different grid configurations. A Kansas raster-based DEM is used for a case study and an inverse distance weighting (IDW) algorithm is used in interpolation experiments.  相似文献   

17.
地学数据共享是地学研究的重要内容,也是挖掘地学数据、避免地学数据重复采集的重要途径,是现代数据密集型科研范式下地学研究的重要基础,因此,如何打破地学数据“孤岛”、实现不同地学数据便捷获取、保障数据安全、提升和扩展地学数据贡献者权益保护是地学数据共享中急需解决的问题。区块链技术的兴起,为地学数据价值外化途径扩充、提升数据安全和地学数据贡献者权益保护带来了新的可能。在系统梳理地学数据共享现状、存在问题、区块链基本原理、特点、底层架构以及应用现状的基础上,探讨区块链技术在地学数据共享中的应用可行性以及应用场景,阐述区块链技术在地学数据共享中的应用挑战,以期为地学数据共享领域区块链相关研究与应用提供参考。  相似文献   

18.
Geospatial data sharing as a significant component of geoscience research. It is also an important means to exploit geoscience data and avoid repeated collection of geospatial data. It is an essential foundation for modern data-intensive geoscience research. Therefore, how to break the geospatial data “island” and realize different geoscience data portable access, secure data security, and promote geospatial data author copyright are urgent problems in geospatial data sharing. The rise of blockchain technology has brought new possibilities for the expansion of the value of geospatial data, the enhancement of data security and the improvement of the protection of the rights of stakeholders in geospatial data. Based on the systematic review of the status quo of data sharing, existing problems, basic principles of blockchain, underlying architecture, characteristics and application status, this paper discusses the application feasibility of blockchain technology in geospatial data sharing, and expounds the application challenges of blockchain technology in geospatial data sharing, in order to provide reference for the research and application of blockchain in geospatial data sharing.  相似文献   

19.
ABSTRACT

The critical infrastructures of industrialized countries depend on an interconnected “system of systems” that physically spans the globe and exists virtually everywhere. Often, the governments and industries responsible for the critical infrastructures are unaware of the extension and integration of the “web” on which their infrastructures rely. The safety of the citizens and the economies of these countries rely on the continuous operation of these systems to provide the services vital to the country and its people. The proliferation of interconnectivity and dependencies of these critical infrastructure systems has led to vulnerabilities, with attacks possible against nearly every country's critical infrastructures from nearly anywhere in the world. The vulnerable infrastructures' systems include banking and financial institutions, transportation systems, electricity and natural gas generation and distribution, petroleum distribution, and phone and cell communications. The threats may originate from unintended incidents, attacks by criminals, terrorists, and adversarial foreign nations with malicious intent, any of which could cause significant damage, bringing the critical systems to a halt. This literature review looks at various aspects of critical infrastructures and the governmental approaches to address the problem of government dependency on the private sector's ownership and control of critical infrastructures.  相似文献   

20.
地理信息元数据及系统   总被引:7,自引:0,他引:7  
作为数字地球重要支撑技术之一的地理信息元数据技术随着信息技术的飞速发展显得越来越重要。该文对现有的典型地理信息元数据内容和标准以及实现系统进行了分析和综合比较,然后对地理信息元数据内容与标准的制订、地理信息元数据系统的建设提出了一点思考,希望能够对相关的研究有所启发。  相似文献   

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