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1.
ABSTRACT

When defining indicators on the environment, the use of existing initiatives should be a priority rather than redefining indicators each time. From an Information, Communication and Technology perspective, data interoperability and standardization are critical to improve data access and exchange as promoted by the Group on Earth Observations. GEOEssential is following an end-user driven approach by defining Essential Variables (EVs), as an intermediate value between environmental policy indicators and their appropriate data sources. From international to local scales, environmental policies and indicators are increasingly percolating down from the global to the local agendas. The scientific business processes for the generation of EVs and related indicators can be formalized in workflows specifying the necessary logical steps. To this aim, GEOEssential is developing a Virtual Laboratory the main objective of which is to instantiate conceptual workflows, which are stored in a dedicated knowledge base, generating executable workflows. To interpret and present the relevant outputs/results carried out by the different thematic workflows considered in GEOEssential (i.e. biodiversity, ecosystems, extractives, night light, and food-water-energy nexus), a Dashboard is built as a visual front-end. This is a valuable instrument to track progresses towards environmental policies.  相似文献   

2.
Abstract

Geospatial simulation models can help us understand the dynamic aspects of Digital Earth. To implement high-performance simulation models for complex geospatial problems, grid computing and cloud computing are two promising computational frameworks. This research compares the benefits and drawbacks of both in Web-based frameworks by testing a parallel Geographic Information System (GIS) simulation model (Schelling's residential segregation model). The parallel GIS simulation model was tested on XSEDE (a representative grid computing platform) and Amazon EC2 (a representative cloud computing platform). The test results demonstrate that cloud computing platforms can provide almost the same parallel computing capability as high-end grid computing frameworks. However, cloud computing resources are more accessible to individual scientists, easier to request and set up, and have more scalable software architecture for on-demand and dedicated Web services. These advantages may attract more geospatial scientists to utilize cloud computing for the development of Digital Earth simulation models in the future.  相似文献   

3.
ABSTRACT

The need and critical importance of global land cover and change information has been well recognized. Although rich collection of such information has been made available, the lack of necessary information services to support its easy access, analysis and validation makes it difficult to find, evaluate, select and reuse them through well-designed workflows. Aiming at promoting the development of the needed global land cover information services, this paper presents a conceptual framework for developing a Collaborative Global Land Cover Information Service (CoGland), followed by discussions on its implementation strategies. The framework supports connected and shared land cover and change web services around the world to address resource sharing, community service and cross-board collaboration needs. CoGland can benefit several recent international initiatives such as Future Earth, and many societal benefit areas. The paper further proposes that CoGland be developed within the framework of the Group on Earth Observations with the support of a number of key organizations such as the United Nations Expert Committee on Global Geospatial Information Management, the International Society for Photogrammetry and Remote Sensing, and International Society of Digital Earth. It is hoped that this paper can serve as a starting point for further discussions on CoGland developments.  相似文献   

4.
ABSTRACT

Turning Earth observation (EO) data consistently and systematically into valuable global information layers is an ongoing challenge for the EO community. Recently, the term ‘big Earth data’ emerged to describe massive EO datasets that confronts analysts and their traditional workflows with a range of challenges. We argue that the altered circumstances must be actively intercepted by an evolution of EO to revolutionise their application in various domains. The disruptive element is that analysts and end-users increasingly rely on Web-based workflows. In this contribution we study selected systems and portals, put them in the context of challenges and opportunities and highlight selected shortcomings and possible future developments that we consider relevant for the imminent uptake of big Earth data.  相似文献   

5.
For landscape models to be applied successfully in management situations, models must address appropriate questions, include relevant processes and interactions, be perceived as credible and involve people affected by decisions. We propose a framework for collaborative model building that can address these issues, and has its roots in adaptive management, computer‐supported collaborative work and landscape ecology. Models built through this framework integrate a variety of information sources, address relevant questions, and are customized for the particular landscape and policy environment under study. Participants are involved in the process from the start, and because their input is incorporated, they feel ownership of the resulting models, increasing the chance of model acceptance and application. There are two requirements for success: a tool that supports rapid model prototyping and modification, that makes a clear link between a conceptual and implemented model, and that has the ability to implement a wide range of model types; and a core team with skills in communication, research and analysis, and knowledge of ecology and forestry in addition to modelling. SELES (Spatially Explicit Landscape Event Simulator) is a tool for building and running models of landscape dynamics. It combines discrete event simulation with a spatial database and a relatively simple modelling language to allow rapid development of landscape simulations, and provides a high‐level means of specifying complex model behaviours ranging from management actions to natural disturbance and succession. We have applied our framework in several forest modelling projects in British Columbia, Canada. We have found that this framework increases the interest by local experts and decision‐makers to participate actively in the model building process. The workshop process and resulting models have efficiently provided insight into the dynamics of large landscapes over long time frames. The use of SELES has facilitated this process by providing a flexible, transparent environment in which models can be rapidly implemented and refined. As a result, model findings may be more readily incorporated into decision‐support systems designed to assist resource managers in making informed decisions.  相似文献   

6.
ABSTRACT

National spatial data infrastructures are key to achieving the Digital Earth vision. In many cases, national datasets are integrated from local datasets created and maintained by municipalities. Examples are address, building and topographic information. Integration of local datasets may result in a dataset satisfying the needs of users of national datasets, but is it productive for those who create and maintain the data? This article presents a stakeholder analysis of the Basisregistratie Adressen en Gebouwen (BAG), a collection of base information about addresses and buildings in the Netherlands. The information is captured and maintained by municipalities and integrated into a national base register by Kadaster, the Cadastre, Land Registry and Mapping Agency of the Netherlands. The stakeholder analysis identifies organisations involved in the BAG governance framework, describes their interests, rights, ownerships and responsibilities in the BAG, and maps the relationships between them. Analysis results indicate that Kadaster and the municipalities have the highest relative importance in the governance framework of the BAG. The study reveals challenges of setting up a governance framework that maintains the delicate balance between the interests of all stakeholders. The results provide guidance for SDI role players setting up governance frameworks for national or global datasets.  相似文献   

7.
ABSTRACT

For evaluating the progresses towards achieving the Sustainable Development Goals (SDGs), a global indicator framework was developed by the UN Inter-Agency and Expert Group on Sustainable Development Goals Indicators. In this paper, we propose an improved methodology and a set of workflows for calculating SDGs indicators. The main improvements consist of using moderate and high spatial resolution satellite data and state-of-the-art deep learning methodology for land cover classification and for assessing land productivity. Within the European Network for Observing our Changing Planet (ERA-PLANET), three SDGs indicators are calculated. In this research, harmonized Landsat and Sentinel-2 data are analyzed and used for land productivity analysis and yield assessment, as well as Landsat 8, Sentinel-2 and Sentinel-1 time series are utilized for crop mapping. We calculate for the whole territory of Ukraine SDG indicators: 15.1.1 – ‘Forest area as proportion of total land area’; 15.3.1 – ‘Proportion of land that is degraded over total land area’; and 2.4.1 – ‘Proportion of agricultural area under productive and sustainable agriculture’. Workflows for calculating these indicators were implemented in a Virtual Laboratory Platform. We conclude that newly available high-resolution remote sensing products can significantly improve our capacity to assess several SDGs indicators through dedicated workflows.  相似文献   

8.
Abstract

With the proposition of the Digital Earth (DE) concept, Virtual Geographic Information System (VGIS) has started to play the role of a Digital Earth prototype system. Many core problems involved in VGIS, such as out-of-core management and interactive rendering of very large scale terrain and image data, have been well studied in the past decades. However, the jitter problem, a common problem in VGIS that often causes annoying visual artefacts and deteriorates the output image quality, draws little attention. In this paper, after an intensive analysis of the jitter problem, a comprehensive framework is proposed to address such a problem while accounting for the characteristics of different data types in VGIS, such as terrain or ocean mesh data, vector data and 3-D model data. Specifically, this framework provides an improved dynamic local coordinate system (DLCS) method for terrain or ocean mesh data. For vector data, the framework provides a simple and effective multiple local coordinate systems (MLCS) method. The framework provides a MLCS method for 3-D model data making full use of the existing local coordinate system of the model. The advantages of the proposed methods over current approaches are analysed and highlighted through case studies involving large GIS datasets.  相似文献   

9.
ABSTRACT

Earth observations and model simulations are generating big multidimensional array-based raster data. However, it is difficult to efficiently query these big raster data due to the inconsistency among the geospatial raster data model, distributed physical data storage model, and the data pipeline in distributed computing frameworks. To efficiently process big geospatial data, this paper proposes a three-layer hierarchical indexing strategy to optimize Apache Spark with Hadoop Distributed File System (HDFS) from the following aspects: (1) improve I/O efficiency by adopting the chunking data structure; (2) keep the workload balance and high data locality by building the global index (k-d tree); (3) enable Spark and HDFS to natively support geospatial raster data formats (e.g., HDF4, NetCDF4, GeoTiff) by building the local index (hash table); (4) index the in-memory data to further improve geospatial data queries; (5) develop a data repartition strategy to tune the query parallelism while keeping high data locality. The above strategies are implemented by developing the customized RDDs, and evaluated by comparing the performance with that of Spark SQL and SciSpark. The proposed indexing strategy can be applied to other distributed frameworks or cloud-based computing systems to natively support big geospatial data query with high efficiency.  相似文献   

10.
Abstract

While significant progress has been made to implement the Digital Earth vision, current implementation only makes it easy to integrate and share spatial data from distributed sources and has limited capabilities to integrate data and models for simulating social and physical processes. To achieve effectiveness of decision-making using Digital Earth for understanding the Earth and its systems, new infrastructures that provide capabilities of computational simulation are needed. This paper proposed a framework of geospatial semantic web-based interoperable spatial decision support systems (SDSSs) to expand capabilities of the currently implemented infrastructure of Digital Earth. Main technologies applied in the framework such as heterogeneous ontology integration, ontology-based catalog service, and web service composition were introduced. We proposed a partition-refinement algorithm for ontology matching and integration, and an algorithm for web service discovery and composition. The proposed interoperable SDSS enables decision-makers to reuse and integrate geospatial data and geoprocessing resources from heterogeneous sources across the Internet. Based on the proposed framework, a prototype to assist in protective boundary delimitation for Lunan Stone Forest conservation was implemented to demonstrate how ontology-based web services and the services-oriented architecture can contribute to the development of interoperable SDSSs in support of Digital Earth for decision-making.  相似文献   

11.
ABSTRACT

Open data are currently a hot topic and are associated with realising ambitions such as a more transparent and efficient government, solving societal problems, and increasing economic value. To describe and monitor the state of open data in countries and organisations, several open data assessment frameworks were developed. Despite high scores in these assessment frameworks, the actual (re)use of open government data (OGD) fails to live up to its expectations. Our review of existing open data assessment frameworks reveals that these only cover parts of the open data ecosystem. We have developed a framework, which assesses open data supply, open data governance, and open data user characteristics holistically. This holistic open data framework assesses the maturity of the open data ecosystem and proves to be a useful tool to indicate which aspects of the open data ecosystem are successful and which aspects require attention. Our initial assessment in the Netherlands indicates that the traditional geographical data perform significantly better than non-geographical data, such as healthcare data. Therefore, open geographical data policies in the Netherlands may provide useful cues for other OGD strategies.  相似文献   

12.
ABSTRACT

Obtaining useful geographic information from the flood of user-generated geographic content (UGGC) data is of significant interest, but comes with challenges in an age of crowdsourcing. To address this issue, we adopt Maslow’s model of human needs to frame UGGC. Synthesizing across literature about volunteered geographic information and participatory GIS, we present a conceptual framework for characterizing collection of UGGC. The framework is composed of multiple dimensions and levels that include perspectives about motivations, participatory methods, and participants. We also articulate four levels of participants (stakeholders, core-engaged participants, semi-core-engaged participants, and engaged citizens) together with four work principles (communication, cooperation, coordination, and collaboration). Finally, a case study describes an example we use to evaluate the conceptual framework for its suitability in design of a UGGC system. We conclude by reflecting on how and why this framework offers a valuable perspective for deriving useful geographic information and offer future research directions.  相似文献   

13.
Distributed hydrologic models are an integral component of spatial decision support systems for watershed management. At these basin (and larger) scales, a common problem in hydrology and other environmental sciences arises from the need to cope with the increasingly sophisticated models and software tools that are used in the management, processing, and analysis of large volumes of data collected from advanced in situ and remote monitoring instruments. The diversity of these tools, and the need for experts and non-experts alike to be able to easily use them, suggests a non-trivial integration problem of building customized systems from disparate (and in many cases proprietary) components. In this paper we address the systems integration problem within the context of a study of surface-subsurface-atmosphere interactions involving soil moisture remote sensing and hydrologic simulation. The simple early steps that were taken highlight the role of the different components and tools in the integration effort. An alternative approach is presented for creating an integrated system, based on a data flow model with the modular components linked within a flexible framework. An example is developed based on established systems integration techniques from the field of computer aided design.  相似文献   

14.
近年来,随着遥感技术的快速发展,遥感对地观测数据获取量与日俱增。在对海量遥感数据的特征提取与表征上,基于深度学习的智能遥感影像解译技术展现出了显著优势。然而,遥感影像智能处理框架和信息服务能力还相对滞后,开源的深度学习框架与模型尚不能满足遥感智能处理的需求。在分析现有深度学习框架和模型的基础上,针对遥感影像幅面大、尺度变化大、数据通道多等问题,本文设计了嵌入遥感特性的专用深度学习框架,并重点讨论了其构建方法,以及地物分类任务的初步试验结果等。本文提出的智能遥感解译框架架构将为构建具备多维时空谱遥感特性的深度学习框架与模型提供有力支撑。  相似文献   

15.
面向服务的分布式地学模型集成框架研究   总被引：8，自引：0，他引：8  
温永宁  闾国年  杨慧  曹丹  陈旻 《遥感学报》2006,10(2):160-168
通过对模型库、GIS与应用分析模型集成方式的探讨，结合未来以分布式资源共享为特征的系统构建模式，提出了面向服务的分布式地学模型集成框架。该框架通过将XML文档对象模型引入到模型定义中，统一了模型数据和功能的定义，基于COM技术实现了模型集成运行服务器和模型服务访问组件。模型服务器扩展了传统模型库的功能，为异构模型提供了集成和运行环境；服务访问组件实现了面向对象的服务访问接口，为应用系统开发提供了一致的集成模式。  相似文献   

16.
The role of GIS in Digital Earth education   总被引：2，自引：0，他引：2  
Abstract

A growing number of educators worldwide have become convinced that geotechnologies – including geographic information systems (GIS), global positioning systems (GPS), and remote sensing – are key technologies to prepare students to be tomorrow's decision makers. Grappling with local, regional, and global issues of the 21st century requires people who think spatially and who can use geotechnologies. Some educators teach geotechnologies as a discipline, emphasising skills. Other educators use geotechnologies as a tool to teach content, such as geography, history, environmental studies, Earth Science, biology, mathematics, economics and other disciplines. Issues such as traffic, population growth, urban sprawl, energy, water, crime, human health, biodiversity and sustainable agriculture are growing in complexity, exist at every scale and increasingly affect people's everyday lives. Each of these issues has a spatial component. Drivers for geotechnology education include educational content standards, constructivism, the school-to-career movement, active learning, citizenship education, authentic practice and assessment, interdisciplinary education, community connections and a sustained, increasing demand for GIS professionals. Digital Earth is an ideal framework for contextualising domains of inquiry. The Digital Earth community can have a significant impact on the growth of geotechnologies in education, and conversely, the growth of geotechnologies in education and society can foster the forward movement of Earth systems concepts.  相似文献   

17.
Abstract

Smart city is the development of digital city; as its main supporting technology, the digital city geo-spatial framework has to be upgraded to the temporal-spatial information infrastructure (TSII). First, this paper proposes the concept and basic framework of smart city and defines the concept of TSII – processes, integration, mining analysis, and share time-stamps geographic data – and the related policy, regulations and standards, technology, facilities, mechanism, and human resources. The framework has four components: the benchmark of time and space, temporal-spatial big data, the cloud service platform and the related supporting environment. Second, the temporal-spatial big data and cloud service platform are elaborated. Finally, an application of TSII constructed by the Xicheng District Planning Bureau in Beijing is introduced, which provides a useful reference for the construction of smart city.  相似文献   

18.
Abstract

The rapid development of physically-based hydrological information and modelling systems has necessitated enhanced data entry and display systems. A 'mapping tool' is developed for the manipulation and display of spatial information, which is a cost-efficient, self-contained utility system that is suitable for use on micro-computers. It has the ability to be integrated as part of any modelling or information system. Diverse applications using the 'mapping tool' are briefly described including resource management systems for planners, mass balance studies in urban catchments and data entry systems for physically based models.  相似文献   

19.
Abstract

The main objective of this study is to assess the relative contribution of the state-of-the-art topo-hydrological factor, known as height above the nearest drainage (HAND), to landslide susceptibility modellling using three novel statistical models: weights-of-evidence (WofE), index of entropy and certainty factor. In total, 12 landslide conditioning factors that affect the landslide incidence were used as input to the models in the Ziarat Watershed, Golestan Province, Iran. Landslide inventory was randomly divided into a ratio of 70:30 for training and validating the results of the models. The optimum combination of conditioning factors was identified using the principal components analysis (PCA) method. The results demonstrated that HAND is the defining factor among hydrological and topographical factors in the study area. Additionally, the WofE model had the highest prediction capability (AUPRC = 74.31%). Therefore, HAND was found to be a promising factor for landslide susceptibility mapping.  相似文献   

20.
Abstract

In recent years, geographical information systems have been employed in a wide variety of application domains, and as a result many research efforts are being devoted to those upcoming problems. Geospatial data security, especially access control, has attracted increased research interests within the academic community. The tendency towards sharing and interoperability of geospatial data and applications makes it common to acquire and integrate geospatial data from multiple organisations to accomplish a complex task. Meanwhile, many organisations have the requirement for securing access to possessed sensitive or proprietary geospatial data. In this heterogeneous and distributed environment, consistent access control functionality is crucial to promote controlled accessibility. As an extension of general access control mechanisms in the IT domain, the mechanism for geospatial data access control has its own requirements and characteristics of granularity and geospatial logic. In this paper, we address several fundamental aspects concerning the design and implementation of an access control system for geospatial data, including the classification, requirements, authorisation models, storage structures and management approaches for authorisation rules, matching and decision-making algorithms between authorisation rules and access requests, and its policy enforcement mechanisms. This paper also presents a system framework for realising access control functionality for geospatial data, and explain access control procedures in detail.  相似文献   

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