共查询到20条相似文献，搜索用时 78 毫秒
1.
现代三维数字地球已成为GIS技术应用的常用前端展现平台,采用的海量高分辨率遥感影像、分层地名数据和DEM数据的数字地球能否提供高效服务成为制约数字地球框架实用性的关键因素。本文对目前流行的由World Wind项目组基于OGC标准实现的WMS服务及通过Geo Server项目实现的地名服务建立基础地理集群服务的方法进行了研究,同时还针对不同分辨率、不同存储模式的的影像数据服务效率给出了实际分析测试结果。 相似文献
2.
针对数字地球的开源框架平台的搭建,研究了OSGEarth数字地球开源库的整体框架、实时地形渲染机制及三维地形场景中的交互响应机制,并结合Qt绘图引擎,设计了基于Qt平台下的数字地球平台,利用该框架实现矢量、影像、高程数据的加载和坐标查询、距离测量、注记符号添加等地理信息查询功能,通过加载Google全球影像与地形数据实现三维地形场景的渲染,实现地理信息查询功能验证了该数字地球平台的可用性,拓展了三维地理信息系统的研究方向。 相似文献
3.
基于Internet/Intranet的开放式地理信息系统Web GIS，为人类共享遥感影像这一人类共同的资源，提供了快捷灵活的手段。尤其是1998年以来，在“数字地球”的设想下，遥感影像数据无疑会在未来“数字地球”建设中占有重要地位。但是，海量遥感影像数据和网络有限带宽这对矛盾严重地影响着遥感影像的充分应用。国际标准化组织（ISO）和图像专家联合小组（Joint Photographic Experts Group,JPEG)于1997年提出的JPEG2000图像标准，将会很好地解决这一矛盾。该文将论述基于该标准的遥感影像，在Web GIS上的应用实现及结构。 相似文献
4.
基于Internet/Intranet的开放式地理信息系统Web GIS，为人类共享遥感影像这一人类共同的资源，提供了快捷灵活的手段。尤其是1998年以来，在“数字地球”的设想下，遥感影像数据无疑会在未来“数字地球”建设中占有重要地位。但是，海量遥感影像数据和网络有限带宽这对矛盾严重地影响着遥感影像的充分应用。国际标准化组织（ISO）和图像专家联合小组（Joint Photographic Experts Group,JPEG)于1997年提出的JPEG2000图像标准，将会很好地解决这一矛盾。该文将论述基于该标准的遥感影像，在Web GIS上的应用实现及结构。 相似文献
5.
6.
7.
基于可量测实景影像的空间信息服务 总被引：17，自引：2，他引：17
讨论了面向第三代Internet和Web2．0模式下的空间信息服务需求，提出了空间信息服务的数字地球影像体系，并给出了一种可量测实景影像数据获取、组织管理以及与4D产品集成的技术途径。首次提出了可量测实景影像空间信息服务体系，对基于可量测实景影像的空间信息服务的前景进行了展望。 相似文献
8.
070401基于可量测实景影像的空间信息服务/李德仁(武汉大学)…//武汉大学学报·信息科学版.-2007,32(5).-377~380讨论了面向第三代Internet和Web 2.0模式下的空间信息服务需求,提出了空间信息服务的数字地球影像体系,给出了一种可量测实景影像数据获取、组织管理及与4D产品集成 相似文献
9.
10.
4D产品的生产和应用系列讲座(二)数字正射影像的生产和应用 总被引：3，自引：0，他引：3
1998年1月31日,美国副总统戈尔在他的报告"数字地球--对21世纪人类星球的理解"中提出数字地球的概念,已经在国内引起了重大的反响.数字地球中的一个重要内容是地面1 m高分辨的遥感影像.我们知道,1:10 000的正射影像,如果其像元分辨率为100 μm,则地面分辨率恰好是1 m.所以,1:10 000的正射影像加上数字地面模型,就是数字地球的重要组成部分. 相似文献
11.
The ability to visualize location and time information on satellite‐generated maps using geographic information systems (GIS) such as Google Earth has enabled researchers with limited mapping expertise to use GIS for a wide range of applications. GIS holds special benefits for research in historical geography involving visualization of events and time‐based changes in geographical information. This article describes a Microsoft Excel VBA application which automatically converts information contained in a Microsoft Excel workbook into a.kml (Keyhole Markup Language) file suitable for display by mapping systems such as Google Earth. The application requires no knowledge of KML or Excel VBA. An example illustrates how the application can be used to trace the Mongol invasion of Eastern Europe. 相似文献
12.
13.
ArcSDE是ArcGIS与关系数据库之间的GIS通道。它允许用户在多种数据管理系统中管理地理信息，并使所有的ArcGIS应用程序都能够使用这些数据。ArcSDE是多用户ArcGIS系统的一个关键部件。它为DBMS提供了一个开放的接口，允许ArcGIS在多种数据库平台上管理地理信息。这些平台包括如果你的ArcGIS需要使用一个可以被大量用户同步访问并编辑的大型数据库，ArcSDE为你提供必要的功能。通过ArcSDE你的ArcGIS可以在DBMS中轻而易举地管理一个共享的、多用户的空间数据库。 相似文献
14.
15.
“数字鸿沟”与地球信息科学的应对 总被引：2，自引：1，他引：2
2003年上半年连续出现的全球性突发事件,是对我国的严峻考验。面对严峻复杂的世界形势,地球信息科学可以大有作为,如建设各类型的地理信息系统,以增强应变能力,制定长远规划,加强基础研究和数据储备,将地球信息科学的先进技术和成果应用于国家应对突发事件和政府决策,提出强强联合,共同攻克难关。 相似文献
16.
A choropleth map is a form of thematic map used to portray the structural characteristics of some particular geographical distribution not apparent in data presented in tabular form. Preparation of a choropleth map starts with the assignment of map features to classes based on the value of a specific feature attribute followed by the association of classes of features with appropriate map colors or symbols. Map features are often geographical regions with naturally or artificially defined boundaries, but choropleth maps can also be prepared by segmenting the area to be mapped into a regular grid of regions. Maps prepared with each grid shaded in an intuitive manner such as blue for grids with the lowest attribute values to red for the highest values can be termed “heat maps”. This technical note describes the HeatMap Microsoft Excel application which converts information contained in a worksheet into a heat map, and then converts the heat map into a file suitable for display using mapping systems such as Google Earth. An example illustrates how the application can be used to visualize the seventeenth century frontier between the Polish/Lithuanian Commonwealth and the Ottoman Empire. 相似文献
17.
《International Journal of Digital Earth》2013,6(10):979-995
ABSTRACTLocation has proven axiomatic as an economic variable throughout human history. Tobler’s first law of geography introduced the importance of location; in that, near things are more related than far things. In an age of digital economies, a new research frontier exists where everything is more related to everything else and has an increased economic value from spatially enabled technology. The accessibility of digital-spatial information has brought economic geographers to a new understanding of markets within a Digital Earth framework. The importance of location to economic value can be expected to grow as the Internet of Things develops in sophistication. New business models enter and disrupt established markets with innovative spatially enabled approaches. A successful penetration of established markets suggests a new business model for financial and functional utility by engaging spatially enabled assets. The second law of geography is introduced as a conceptual framework to comprehend the economic potential of spatially enabled information. A comparative analysis of non-spatial versus spatial web agents provides a quantitative framework to demonstrate the benefits of the Digital Earth economy. 相似文献
18.
19.
ABSTRACTThe Moon, Earth’s only natural satellite, is a potential new platform for Earth observation. Moreover, with the wide applicability of the angular information from remote sensing data, it has been attracting increasingly more attention. Accordingly, this study focuses on the angular characteristics of Moon-based Earth observations. Using ephemeris DE430 and Earth orientation parameters, the position and attitude of the Sun, Earth, and Moon were obtained and their coordinates normalized to a single framework using coordinate transformations between the related reference systems. Then, an angular geometric model of Moon-based Earth observations was constructed, and the corresponding angular algorithms were presented. The results revealed the angular range and distribution characteristics of Moon-based Earth observations. For every point on the surface of the Earth, the view and solar zenith angles all vary widely, which decreases with increasing latitude. The view and solar zenith angles all vary widely with the largest range of values in the equatorial and polar regions and a smaller range of values in mid-latitudes. Furthermore, the range of solar angles of Moon-based Earth observations is the same as that of all-time solar angles, indicating the potential for monitoring and understanding large-scale geoscientific phenomena using Moon-based Earth observations. 相似文献
20.
The role of GIS in Digital Earth education 总被引：2，自引：0，他引：2
《International Journal of Digital Earth》2013,6(4):326-346
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