共查询到19条相似文献，搜索用时 203 毫秒
1.
LIANG Yong LU Xiushan ZHANG Degui LIANG Fu 《地球空间信息科学学报》2002,5(1):68-73
This paper deals with the content,purpose and significance of digital agriculture,and gives a brief introduction to digital earth,digital China and digital agriculture abroad.The main content of digital agriculture includes the construction of database,Metadata standard,monitoring system,forecasting and decision-making system,information-releasing system.The main technical supports of digital agriculture are 3S technology,Metadata management technology,fast-handling technology of remote sensing,the technology of computer wide-band network and virtual reality,intelligent agriculture machinery and field real-time information collecting technology.The advantages of implementing digital agriculture in China and the problems worthy of attention are pointed out as well. 相似文献
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ZHANGQiaoping IsabelleCouloigner 《地球空间信息科学学报》2004,7(2):89-95
This paper presents a tramework for road network change detectlon In order to upctate the Canadian National Topographic DataBase (NTDB). The methodology has been developed on the basis of road extraction from IRS-pan images (with a 5.8 m spatial resolution) by using a wavelet approach. The feature matching and conflation techniques are used to road change detection and updating. Elementary experiments have showed that the proposed framework could be used for developing an operational road database updating system. 相似文献
3.
WAN Xiaoxia 《地球空间信息科学学报》2000,3(4):48-53
This paper presents the hypermedia data model based on the infinity RS image information system we have developed.The hypermedia data model consists of different semantic units called nodes,and the associations between nodes are called links.This paper proposes three kinds of nodes (interior node,physical node and complex node) and two kinds of links (plane network structure link,hyper-cube network structure links).The hypermedia information system,based on the model and the basic data layer (the infiniy RS image),represents a digital globe.An approach to the "Getting Lost in the Hyper-space" problem is presented.The approach using the hypermedia data model is an efficient way of handling a large number of RS images in various geographical information systems. 相似文献
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Transect-based three-dimensional road modeling and visualization 总被引：3，自引：0，他引：3
LIQingquan TANGLuliang ZUOXiaoqing LIHanwu 《地球空间信息科学学报》2004,7(1):14-17
On the basis of the study on road elements and the existing three-dimensional road data models, this paper puts forward the transect-based road modeling, resolves the modeling of the simplest road with two road transects, and fulfils the visualization of the road. OpenGL is applied as the tool of visualization. The map texture technology, LOD algorithm and dynamic multi-differentiating texture technology are of benefit to the construction of 3D road GIS, and improve the speed of roaming and effective visualization. This paper also disusses the combination of 2D digitall road map and 3D road scene, and the dynamic response between them. Finally, on the basis of the research on the transect-based road model, this paper develops the three-dimen-sional road geographic information system called virtual road ( VRoad ), which not only supplies road designers with a set of tool which can turn the designed 2D road data into 3D road and the high road assistant function area in computer, but also supplies the road management with a set of tool which can realize the road real time and interactive roaming, high-efficiency management. 相似文献
5.
Shine-WeiLin Chih-HongSun Chin-HanChen 《地球空间信息科学学报》2004,7(1):31-38
This paper integrates genetic algorithm and neural network techniques to build new temporal predicting analysis tools for geographic information system (GIS). These new GIS tools can be readily applied in a practical and appropriate manner in spatial and temporal research to patch the gaps in GIS data mining and knowledge discovery functions. The specific achievement here is the integration of related artificial intelligent technologies into GIS software to establish a conceptual spatial and temporal analysis framework. And, by using this framework to develop an artificial intelligent spatial and temporal information analyst (ASIA) system which then is fully utilized in the existing GIS package. This study of air pollutants forecasting provides a geographical practical case to prove the rationalization and justness of the conceptual temporal analysis framework. 相似文献
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SUIHaigang LIDeren GONGJianya 《地球空间信息科学学报》2003,6(4):44-50
Up to now, detailed strategies and algorithms of automatic change detection for road networks based on GIS have not been discussed. This paper discusses two different strategies of automatic change detection for images with low resolution and high resolution using old GIS data, and presents a buffer detection and tracing algorithm for detecting road from low-resolution images and a new profile tracing algorithm for detecting road from high-resolution images. For feature-level change detection (FL-CD), a so-called buffer detection algorithm is proposed to detect changes of features. Some ideas and algorithms of using GIS prior information and some context information such as substructures of road in high-resolution images to assist road detection and extraction are described in detail. 相似文献
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This paper deals with transformation procedures for observed GPS data from the world geodetic system WGS-84 into the national geodetic grid datum S-UTCN(system of united trigonometric cadaster network) and Baa(the Baltic Sea after adjustment).Transformation from WGS-84 into SUTCN is performed most frequently by means of the 7-element Helmert transformation with three identical points.Geodetic network was adjusted by two ways. 相似文献
8.
LIUZhengrong 《地球空间信息科学学报》2003,6(2):63-68
Automatic extraction of road and linear structure from remote sensing images is a very important problem.This paper analyses several existing methods of the automatic road and linear structure extraction by using some multi-spectral remote sensing images acquired from different spatial resolutions,districts and road characteristics. Their advantages and disadvantages have been generalized. 相似文献
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针对车载导航、地图网站等应用中路网要素之间交通关系维护的难题,提出一种支持路网要素交通关系自动化的智能过程模型,将路网要素交通关系自动化过程理解为由路网要素间的空间和语义关系、规则集和控制系统组成的产生式系统.该产生式系统可在路网要素空间和语义信息基础上,通过定义可扩展的交通关系规则集,自动化地生成符合应用需求的路网要素间的交通关系.此外,在该产生式系统中引入触发器概念监控和响应几何网络及其交通关系规则集的变更,实时更新逻辑网络中的连通关系信息,实现几何网络、规则集和逻辑网络三者的一致性.同时,提出路网要素交通关系处理的控制策略和关键流程,并对该智能网络模型的有效性进行了验证.Abstract： Maintaining the traffic connectivity relations between road features has always been a time consuming task for in-vehicle navigation, map website, and other traveling service related applications. Such a task has been commonly conducted artificially and inevitably inefficient, yet makes data quality control difficult. Considering the intrinsic rules of traffic connectivity formed by the geometrical structures, spatial and semantic relationships between road features in city road networks, an intelligent processing model is set forward in this paper for traffic connectivity automation. It is argued that traffic connectivity automation between road features is fundamentally a production system composed of the spatial and semantic relations between road features, connectivity rules and control system. With the implementation of an extendable connectivity rule set, the traffic connectivity relations between road network features are built automatically based on the spatial and semantic information of road network. The trigger concept is adopted to monitor and respond the changes in geometrical network and connectivity rules, and then dynamically updates the traffic connectivity between road network features in logical network so as to guarantee the consistence between geometrical network, connectivity rules and logical network. A series of control strategies and a conducting engine are developed to maintain the traffic connectivity relations. A case study conducted on a real road network verifies the effects of the proposed intelligent model. 相似文献
10.
Spatio-temporal GIS data model based on event semantics 总被引：3，自引：0，他引：3
XUZhihong BIANFuling 《地球空间信息科学学报》2003,6(3):43-47
There are mainly four kinds of models to record and deal with historical information. By taking them as reference, the spatio-temporal model based on event semantics is pro-posed. In this model, according to the way for describing an event, all the in-formation are divided into five do-mains. This paper describes the model by using the land parcel change in the cadastral information system, and ex-pounds the model by using five tables corresponding to the five domains.With the aid of this model, seven ex-amples are given on historical query,trace back and recurrence. This model can be implemented either in the ex-tended relational database or in the ob-ject-oriented database. 相似文献
11.
介绍了车载道路信息采集和更新系统 (CRICUS)的设计和研究进展。该系统利用 3S集成技术采集道路信息并生成数字道路网数据库。初步实验表明 ,该系统的定位精度可达 1m。 相似文献
12.
欧小善 《测绘与空间地理信息》2009,32(1)
随着信息技术的飞速发展和计算机网络的普遍使用.传统的公路管理与其他产业一样正面临着一场革命.信息技术在公路管理中正发挥着越来越大的作用.如何开发一个适用于公路部门的地理信息管理系统是值得研究的问题.本文针对基于C/S网络结构模式开发公路地理信息管理系统的有关技术问题进行有益的探讨. 相似文献
13.
道路网是最重要的地理空间要素之一,空间数据融合能够把不同来源道路空间数据或信息加以结合,以获得信息量更丰富或更适于处理、分析、决策的新的数据集。传统的方法受限于道路网数据模型、属性数据类型以及缺少唯一标识的属性信息,道路网融合方法多以各个弧段或道路的位置、形状、方向等几何特征进行匹配,而忽略了道路的语义匹配。本文在数据来源与技术分析的基础上,提出了一种在工程化应用中可行的语义与几何相结合的道路网匹配方法,并通过FME实现空间数据融合,旨在为两个或多个道路网数据融合、联动更新提供方法参考。 相似文献
14.
基于特征基元的高分辨率遥感影像道路网自动提取技术 总被引：1，自引：0，他引：1
高分辨率遥感道路网络的自动提取在城市信息更新等方面具有非常重要的意义。在综述国内外道路信息提取进展的基础上,本文提出一套基于特征基元的道路网提取方法体系。即采取自下而上的研究路线("影像像元—特征基元—道路单元—道路网络"):首先通过影像大尺度的区域划分获取道路区域,在此基础上进行小尺度分割,提取出特征基元;然后根据基元的形态、走向、亮度、纹理等特征对基元进行模式分类,识别出道路单元;最后根据道路网语义规则将道路单元进行形态学处理及拓扑连接,形成道路网络。 相似文献
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随着科技发展,道路导航产业正在蓬勃发展,而导航的基础数据采集和更新正是制约导航产业的瓶颈,本文通过移动道路测量系统采集导航数据并对其检测,探讨移动道路测量系统在导航数据获取和更新中的应用,并对移动道路测量系统在导航产业中的前景进行展望。 相似文献
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轻便型移动测量系统能高效率、高速度地采集道路两旁丰富的地物信息,可以为城市三维建模提供丰富、准确的基础点云数据。本文结合系统构成、工作原理、全景影像采集及点云数据采集的特点,研究了基于轻便型移动测量系统的城市三维建模技术解决方案,满足了实际工程需要。 相似文献
19.
一种基于线特征的道路网变化检测算法 总被引：6，自引：0，他引：6
提出一种基于线特征的道路网变化检测算法。首先根据边缘的梯度信息从多时相遥感图像中提取变化的线特征;然后根据变化线特征的局部特性,检测出与道路模型相符合的变化道路段;最后通过道路网的全局约束条件,进行变化道路段的连接,实现变化道路的检测。提出的道路网变化检测算法将边缘的相位和幅度信息作为变化检测的判定依据,从而避免了道路的匹配与比较工作,降低了变化检测算法的复杂度,具有很强的实用性。将本文提出的方法用于多时相遥感图像的道路网变化检测,从实验结果可以看出该方法的有效性。 相似文献