Research On Query System Of Urban Transportation Infrastructure Based On GIS

At present, the planning, construction, operation management and basic information technology of city comprehensive transportation system lag behind the rapid urbanization and city development process, which has become the bottleneck of the urban economic and social development.The basic traffic information are the core of the integrated city transport system, it is the important decision-making support to scientific planning, construction, management and efficient operation of city's comprehensive transportation system .But the existing various types of traffic information subsystem lack of information sharing, resulting in duplicate construction and waste of resources, not only can't provide a scientific basis in decision making for managers, but also unable to provide high-quality information Service for travelers. Therefore, research and develop the basic urban traffic information system has become an inevitable requirement of a city's sustainable development.Integrating source in different sectors of transportation infrastructure and related information; research-based on GIS technology such as data acquisition, recording, editing, output;carrying out macro-traffic census data; developping the capabilities of GIS spatial data query and management; analysis processing basic information on various types of traffic; building basic urban transportation information platform;to study the release technology under the modern network-based information;to explore regional city traffic information share mechanism with the basic management model; to provide a scientific decision support for managers ; to provide accurate, a variety of traffic information services for the travelers;have been a feasible and great practical significance problem in the field of transportation.With the continuous traffic problem becoming more and more serious and the development of technology related fields, based on geographic information systems for the transport of geographic data and attribute data releasing and sharing of query and analysis provides a new way, which has become hot spots of research at home and abroad.This paper mainly takes Jilin City Changyi areas as transportation infrastructure query system model, the region covers almost all the conventional sense of the transportation infrastructure ,which makes research more practical.mainly to do the following research work:Transportation infrastructure of spatial data acquisition and processing method.first of all introduce several conventional acquisition methods of the production of digital map data required.This article set up a data collection group in the development process. Collected data is divided into three formats: GIS in vector data (SHP format), which are part of the transportation infrastructure existing as a background layer including: administrative divisions, water, roads, housing, places Note, road Note, the Housing Note; CAD Layer (*. dwg format) are CAD engineering drawings ,which are mostly the main trunk road ,sub-distributors, Hutong, private parking, on-street parking, signal light, Station etc in Changyi region. Many of them are CAD Hand drawings with close accuracy, in full accordance with the requirements of specific construction drawing; Grid map: namely, aerial films, get the entire City of aerial maps, can be used as tracking layers when rendering vector map. Import three kinds of data in simple data format into GIS software (SuperMapDeskpro2008) as a unified data format; then set up a BeiJing1954 unified coordinate system on the data; Integrate the dataset; Registrate, topology, and Note different layers.Transportation infrastructure spatial query algorithm research is to demarcate a polygon and query the infrastructure facilities in it ,such as parking and signal Lights and so on.Therefore need to use the query algorithm to determine whether the point at polygon in GIS . Based on the analysis of the basic principles of conventional ray method and its advantages and disadvantages, this paper designs an improved discriminant algorithm to judge the relationship between point and the polygon. This algorithm judge the ray direction in the pre-processing stage, so that it down through the least edge, so a reduction of ray intersection with the number of polygons improves the efficiency of the query. In this paper, we define that there are four possible ray direction: parallel to X-axis, pointing to the positive or negative; parallel to Y-axis, pointing to the positive or negative. This method reduces the complex calculation for the singularity situation.According to the specific needs of the application and analysis ,we design the transportation infrastructure database.The difference between Transportation infrastructure database and common database is that the Transportation infrastructure database have the expression of its many geographical entities spatial data and their topological relationships, which makes the data storage management and design method more complex than the common database. According to the basic principles of database design and process: conceptual design, logical design, physical design, database design, we design all of the database table of transportation infrastructure. Using the data structure in SuperMapDeskpro2008: data sources, data sets, data items and Hierarchy SuperMap SDX + spatial data engine,we set up a transportation infrastructure database.Jilin City Changyi District of transportation infrastructure query sample Design and implem-ention. The query system uses the secondary development of integrated way by GIS components SuperMapObjects in VB6.0 environment. System achieves three main functions .Firstly,a basic operation such as a map to enlarge, narrow, roaming, full-map etc; Secondly ,data analysis such as buffer space for the regional analysis, property tracking settings, layer topology operations, spatial relationships query etc; Thirdly, special subject inquiries of Transportation infrastructure in the area ,such as trunk road, secondary road, parking lots, train stations, traffic lights and other inquiries.Transportation infrastructure are are essential support and protection to the economic and social development. Increased transportation infrastructure investment can promote economic growth, stimulate domestic demand and industrial development, absorb many workers. The important role of transportation infrastructure not only laid a foundation for economic growth, but also promote the urbanization which is characterized by production and population concentration. The birth of GIS provides a new, intuitive and advanced tools for the modernization of transportation infrastructure and equipment management, As inquiry of GIS technology are the most basic functions in the transportation infrastructure management, the research on query technology of urban transportation infrastructure based on GIS is one thing which owns important and practical meaning.