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991.
科学观测数据的海量增长,使得旨在实现资源互操作的虚拟观测台(VO)应运而生,并迅速受到相关学科的支持和重视。国际虚拟天文台联盟(IVOA)、行星科学数据系统(PDS)和空间物理归档检索抽取标准(SPASE)等数据组织,正加快制定数据管理模型,推动VO的发展和跨学科应用。结合空间科学应用研究的特点,在借鉴国内外天文和空间科学VO研究成果的基础上,提出了一种针对空间科学数据的Hybrid型VO体系结构,并基于此体系结构发展了一个支持同步收割、格式化管道和事件关联发现的空间科学VO原型。实践和应用结果表明,基于这种体系结构建立的VO在解决全局资源的实时同步、异构应用的高度集成和面向科学问题的数据发现等问题上,有一定的普适性。 相似文献
992.
This paper presents the studies of the refining of IKONOS-2 RPC, the transform of the datum, the mode of the control point distribution and the method of IKONOS stereo triangulation, so that IKONOS imagery can be used to collect the precise geospatial data and produce the large scale map. The transform between the IKONOS-2 image space and the national coordinate system based on the RPC have been developed, and the results of block adjustment with various control schemes in a practical project near Himalayas have been examined and analysed. The encouraging results of high positioning accuracy have been obtained. 相似文献
993.
Accurate Attribute Mapping from Volunteered Geographic Information: Issues of Volunteer Quantity and Quality 总被引:3,自引:0,他引:3
G. M. Foody L. See S. Fritz M. van der Velde C. Perger C. Schill 《The Cartographic journal》2013,50(4):336-344
Crowdsourcing is a popular means of acquiring data, but the use of such data is limited by concerns with its quality. This is evident within cartography and geographical sciences more generally, with the quality of volunteered geographic information (VGI) recognized as a major challenge to address if the full potential of citizen sensing in mapping applications is to be realized. Here, a means to characterize the quality of volunteers, based only on the data they contribute, was used to explore issues connected with the quantity and quality of volunteers for attribute mapping. The focus was on data in the form of annotations or class labels provided by volunteers who visually interpreted an attribute, land cover, from a series of satellite sensor images. A latent class model was found to be able to provide accurate characterisations of the quality of volunteers in terms of the accuracy of their labelling, irrespective of the number of cases that they labelled. The accuracy with which a volunteer could be characterized tended to increase with the number of volunteers contributing but was typically good at all but small numbers of volunteers. Moreover, the ability to characterize volunteers in terms of the quality of their labelling could be used constructively. For example, volunteers could be ranked in terms of quality which could then be used to select a sub-set as input to a subsequent mapping task. This was particularly important as an identified subset of volunteers could undertake a task more accurately than when part of a larger group of volunteers. The results highlight that both the quantity and quality of volunteers need consideration and that the use of VGI may be enhanced through information on the quality of the volunteers derived entirely from the data provided without any additional information. 相似文献
994.
为克服传统的突变模糊公式用于室内空气评价不能普适、通用的局限,适当设定指标参照值和指标值的规范变换式,使室内空气同级标准不同指标的规范值差异尽可能小,从而用规范值表示的各指标皆与某个规范指标等效。因此任意多项指标的室内空气质量的突变模型均可用若干个尖点突变和(或)燕尾突变两种突变模型组合表示。用突变模糊指数公式对2个室内空气质量评价结果与实况相符合,基于指标规范变换的室内空气质量突变模糊指数公式具有形式简洁、计算简单和普适通用的特点。 相似文献
995.
996.
王冲 《成都信息工程学院学报》2005,20(6):751-754
随着市场经济体制的建立,中央政府宏观调控能力的提高,财政金融政策将更好地作用于科技与教育,促进科教兴国战略的实施。市场规律与科技教育规律约束下的财政金融政策利用市场机制传导模型的建立,运用数学模型来阐述了财政金融政策通过市场机制作用于科技教育的机理。 相似文献
997.
In 2001, the four global change research programmes ‘urgently’ called for ‘an ethical framework for global stewardship and strategies for Earth System management’. Yet this notion of ‘earth system management’ remains vaguely defined: It is too elusive for natural scientists, and too ambitious or too normative for social scientists. In this article, I develop an alternative concept that is better grounded in social science theory: ‘earth system governance’. I introduce, first, the concept of earth system governance as a new social phenomenon, a political programme and a crosscutting theme of research in the field of global environmental change. I then sketch the five key problem structures that complicate earth system governance, and derive from these four overarching principles for earth system governance as political practice, namely credibility, stability, adaptiveness, and inclusiveness. In the last part of the article, I identify five research and governance challenges that lie at the core of earth system governance as a crosscutting theme in global change research. These are the problems of the overall architecture of earth system governance, of agency beyond the state, of the adaptiveness of governance mechanisms and of their accountability and legitimacy, and of the modes of allocation in earth system governance—in short, the five A's of earth system governance research. 相似文献
998.
发挥后发优势,实现生产跳跃式发展,是我国特别是中西部地区加快重要战略方针,为发挥好后发优势,应当研究“新经济”所昭示的新趋势和新经验,研究实现跨越式发展的规律性,客观和主观条件,理清思路,采取一些特殊措施,尤其是突出“第一生产力”的地夹和作用。 相似文献
999.
关于数字地磁台站观测系统的发展与观测资料应用的一点思考 总被引:1,自引:0,他引:1
针对地球科学和国家建设对地磁观测与研究的需求,结合“九五”地磁台站观测技术数字化改造,对地磁台站观测系统的发展及数字观测资料的应用提出了一些见解。 相似文献
1000.
21世纪的地球信息科学及其应用 总被引:6,自引:2,他引:6
分析了地图学、遥感、地理信息系统及全球定位系统的发展 ,为地球信息科学的建立奠定了基础。论述了地球信息科学的内涵、理论基础、技术体系以及地球信息图谱等基本概念 ,阐述了地球信息科学在资源清查与管理、经济与社会可持续发展规划决策与管理、城市规划与现代化管理、农业规划决策与生产管理、灾害预测与灾情评估、环境污染与生态变化监测、全球变化监测与研究等方面的应用前景。 相似文献