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201.
This paper presents the basic concepts and principles, data structure and high efficient spatial index for multi-resolution image database. The database is characterized by arrangement of multi-resource image data and seamless mosaic, distribution-based storage and management, integration with other spatial database software such as GeoStar and GeoGrid developed by Wuhan Technical University of Surveying and Mapping. 相似文献
202.
The research work has been seldom done about cloverleaf junction expression in a 3-dimensional city model (3DCM). The main reason is that the cloverleaf junction is often in a complex and enormous construction. Its main body is bestraddle in air, and has aerial intersections between its parts. This complex feature made cloverleaf junction quite different from buildings and terrain, therefore, it is difficult to express this kind of spatial objects in the same way as for buildings and terrain. In this paper, authors analyze spatial characteristics of cloverleaf junction, propose an all-constraint points TIN algorithm to partition cloverleaf junction road surface, and develop a method to visualize cloverleaf junction road, surface using TIN. In order to manage cloverleaf junction data efficiently, the authors also analyzed the mechanism of 3DCM data management, extended BLOB type in relational database, and combined R-tree index to manage 3D spatial data. Based on this extension, an appropriate data structure for cloverleaf junction in 3DCM is proposed. 相似文献
203.
In this paper, the entity-relation data model for integrating spatio-temporal data is designed. In the design, spatio-temporal data can be effectively stored and spatiao-temporal analysis can be easily realized. 相似文献
204.
Salt affected soils occupy significant areas in western and central India manifested by the arid and semiarid climate, sandy/clayey soil texture, absence of natural drainage, and inadequate infrastructure and irrigation development. These soils are productive following reclamation and appropriate management. The National Remote Sensing Agency, Hyderabad (India) published state-wise maps of salt affected soils in India on 1:250,000 scale using a legend that includes physiography, soil characteristics, and the aerial extent of the mapping units. In the analogue form, voluminous data contained in such maps were difficult to handle by users of varied backgrounds. An attempt was made to prepare a computerized database of salt affected soils for easy access, retrieval, and manipulation of spatial and attribute data useful for management of salt affected soils. The salt affected soils maps were prepared, for Rajasthan, Gujarat, Madhya Pradesh, and Maharashtra states, overlaying digitized layers of SAS polygons and the Survey of India basemap using the ILWIS (Integrated Land and Water Information System) software. GIS was used to prepare a composite (master) database of western and central India that showed the extent and distribution of salt affected soils. A relational database was prepared combining the digitized polygons with soil characteristics such as nature and degree of salinity (presence of higher concentration of neutral salts and neutral soil reaction), sodicity (presence of higher concentration of basic salts and alkaline reaction) and ground coverage. The regional and zonal databases of salt affected soils were prepared at a suitable scale overlaying agro-climatic regions agro-climatic zones. Spatial relation of salt affected soils with physiography, climate, geology, and agro-eco-sub-regions were evaluated employing map calculations in GIS. Saline soils were prevalent in Gujarat, and Rajasthan while sodic soils were dominant in Maharashtra and Madhya Pradesh. These were distributed primarily in the arid (B) plain of Rajasthan, alluvial (A) and coastal (D) plains of Gujarat, and peninsular plain (F) of Maharashtra and Madhya Pradesh. It occupied 2,596,942 ha (78%) in the western (Rajasthan and Gujarat) and 733,608 ha (22%) in the central (Madhya Pradesh and Maharashtra) regions. The SAS occupied 3.3 million ha in the western and central region constituting 50% of the total salt affected soils in India. The saline and sodic soils occupied 2,069,285 ha (62%) and 1,261,266 ha (38%), respectively. 相似文献
205.
介绍了新疆地震应急基础数据库的构成、数据处理和建库及数据库在地震应急指挥技术系统中发挥的作用等。解决了多源数据的处理和整合、多种数据库之间的协同和关联、海量数据的集成等问题。 相似文献
206.
旨在探讨农村集体土地所有权数据库建设方法.以西吉县为例,基于2011年度土地变更调查数据库,在野外实地权属调查基础上,以GIS技术为手段建立标准化农村集体土地所有权确权登记发证数据库,并对该数据库建设流程进行了介绍.科学建立数据库可以更好地实现集体土地所有权数据科学、灵活、安全和高效管理,为保护农民集体土地合法权益提供更为有效的依据和手段. 相似文献
207.
传统的数据库模型适合于表示数字字母数据,难以处理复杂的空间数据。面向对象的语义数据模型克服了传统数据模型的许多不足,越来越多地应用于计算机科学各个领域。本文先描述了面向对象的语义数据模型,然后介绍了建立于这种模型基础上的空间数据库实验系统 spobase。 相似文献
208.
209.
基于MapInfo的钻孔柱状图的绘制 总被引:1,自引:0,他引:1
本文介绍了基于MapInfo的钻孔柱状图自动成图技术,阐述了钻孔数据库和岩性样式库的设计过程以及钻孔柱状图自动成图系统的实现流程、关键技术.并运用OLE技术,以VB 6.0,MapInfo 7.0和SQL Server 2000为开发环境,以实测钻孔数据资料为基础,实现了钻孔数据的管理和钻孔柱状图的自动生成,极大地提高... 相似文献
210.
以太仓市建设用地管理的实际应用需求为背景,设计并构建了一个典型的县级市建设用地分类信息管理系统,该系统综合运用了空间数据库、ArcGIS Engine与Web Server技术,集成"天地图"的地理信息服务资源,实现了用地数据的精细化分类查询统计、动态更新和信息共享,为基层国土资源部门的建设用地管理、规划和决策提供全面、可靠的技术保障。 相似文献