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111.
广东省交通运输厅从2012年起,组织分期研究开发基于地理信息系统的广东省综合运输体系规划信息平台(简称"平台"),旨在建立健全统一的全省交通运输业数据采集、发布标准及技术管理规范,分别构建5大类运输方式线网及重要的运输枢纽站场节点的多级图层,叠加形成全省综合运输体系布局规划"一张图"。"平台"采用4层设计,依托后台管理、应用分析和综合展示3大子系统,搭建了基础地理信息、经济社会、交通运输现状、综合运输体系规划成果及其他共5大类数据库,"平台(一期)"于2014年3月26日通过验收,实现了多维度、多视角展示和查询交通运输业数据成果的预期功能。研究实践将力促综合运输体系规划研究和决策方式实行根本性变革。 相似文献
112.
通过开展地理国情普查工作,可以掌握我国地理国情基本要素、自然地表覆盖、生态及人类活动的基本情况,丰富的地理国情普查成果为政府、企业和公众提供客观、权威、丰富的地理国情信息,服务社会科学发展。移动地理信息作为当前的研究热点,为地理国情普查成果的推广和应用提供了平台。 相似文献
113.
A pioneer research work was carried out by investigators engaged in surveying and mapping for describing ancient Chinese timber buildings by 3D frame graphs with a computer. Users can know the structural layers and the assembly process of these buildings if the frame graphs are processed further with a computer model. This can be implemented by computer simulation technique. This technique display the raw data on the screen of a computer and interactively manage them by combining technologies from computer graphics and image processing, multi-media technology, artificial intelligence, highly parallel real-time computation technique and human behavior science. This paper presents the implementing procedure of lignification simulation for large-sized wooden buildings as well as 3D dynamic assembly of these buildings under the 3DS MAX environment. The results from computer simulation are also shown in the paper. 相似文献
114.
针对现有的旅游信息化产品往往只提供对于旅游主、客体自身的属性特征信息的发布与查询功能,而很少对其空间特征信息,以及空间信息的相互关系进行发布、查询与分析,不能让用户对旅游目的地产生直观、形象的认识,面向旅游者、旅游企业和村镇管理部门,集成WEBGIS技术、多媒体技术、Web3D技术和虚拟现实技术,利用Commercial Off-The-Shelf(COTS)软件组件开发村镇民俗旅游景观三维展示构件。并结合村镇民俗旅游景点的平面、空间、图形、三维等多种漫游方式,对不同资源类型、不同区域自适应展示旅游景观,实现立体展示村镇的风景名胜、风土人情、休闲娱乐、旅游交通等,深入挖掘村镇地方特色,搭建对外宣传的窗口,促进民俗文化交流,保护优秀传统民俗旅游资源,势在必行。 相似文献
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116.
Some traditional methods, such as the velocity-azimuth display (VAD) and the velocity-azimuth processing (VAP), have been widely usedto retrieve the 3-D wind field from single-Doppler radar data because of their relative conceptual and practical simplicity. The advantage of VAD is that it is not affected by small-scale perturbations of the radial wind along the azimuth, to which the VAP method is very sensitive. Nevertheless, the spatial resolution of the VAD method is very poor
compared to the VAP method.
We show, in this study, that these two retrieval methods are actually related with each other and they are two special applications of a retrieval function based on the azimuthal uniform-wind assumption for a given azimuthal interval [θ1, θ2]. When using this retrieval function to retrieve wind fields, the azimuthal interval used in retrieval can be adjusted according to the requirement of smoothness or resolution. The larger (smaller) the azimuthal interval is, the coarser (finer) the horizontal resolution of retrieved wind field is, and the more insensitive (sensitive) the retrieval method is to small-scale perturbations. Because the full information within the azimuthal interval [θ1, θ2],instead of the information at two terminal points only, i.e., azimuths θ1 and θ2, is used to retrieve the wind fields, this method is referred to as the integrating VAP (IVAP) method, wherein the horizontal wind field is retrieved by using the Doppler velocity over the part of circumference, delimited by the given azimuthal interval times the scan radius. By contrast,the VAP method uses only the velocities at two terminal points of the given azimuthal interval. Therefore, the IVAP method has a filtering function, and the filtering rate can be controlled by adjusting the azimuthal interval. The filter such as that used in the pre-processing of the VAP method is no longer necessary for the IVAP method. When the retrieval azimuthal interval is as large as a whole circumference, the IVAP becomes the VAD. On the other hand, if only two neighboring azimuthal data are used, the IVAP becomes the VAP.
The frequency response function of IVAP indicates that the IVAP method can filter out shortwaves, and a larger azimuthal interval leads to stronger filtering ability, therefore a smoother retrieved wind field.
The shortwave filter function of the IVAP method is tested by an ideal experiment wherein the radar observations are artificially created by a uniform flow superposed with random disturbances. The VAP and IVAP methods are used in wind retrieval, respectively, and give different results for different azimuthal intervals (i.e., 6°, 12°, 24°, and 48°). Because the VAP method is sensitive to small disturbances, the retrieved winds have larger errors for all different azimuthal intervals. However, the retrieved wind by the IVAP method has smaller errors when the azimuthal interval is larger due to its shortwave filter function.
An experiment for an idealized linear wind field is also carried out to demonstrate the effect of the retrieval azimuthal interval on the IVAP method. The results show that a short interval gives the retrieval close to the “true" wind field with a linear distribution. When increasing the interval, the retrieval is smoothed and can represent only the mean wind field. 相似文献
117.
118.
为提高气象数据传输的灵活性,采用一种安装方便、性价比较高的无线模块来传输数据.常见气象仪器有一套独立的数据接收显示软件,但无法综合显示.开发一款软件,将VPF-730实时天气现象仪、WEATHERPAK-2000自动气象站数据和串口摄像头图像进行综合对比显示,并提供数据存储及历史数据查询基本功能.经实验验证,该系统运行稳定,数据显示效果较好. 相似文献
119.
王宪民 《测绘与空间地理信息》2005,28(1):79-80
介绍了在数据库建设过程中,通过在ArcSDE Geodatabase中手工创建栅格目录表,对数据库中单独存储的栅格数据实现无缝显示。 相似文献
120.
介绍了酸法地浸采铀工艺信息技术的显示,在长期生产和科研实践的基础上,总结归纳了酸法地浸采铀工艺的基本信息技术,以及如何利用这些信息对地浸开采实现有效的判断和调控,这些内容是地浸工作者必备和需要掌握的重要开采技术和手段。 相似文献