Brief Introduction of Geographic Information System of Henan Agricultural University

This major is a newly opened major of Henan Agricultural University 10, which is located in the Forestry Department of Forestry College. Although it is a young major, it has a good development prospect. It is recommended to go to (Henan Agricultural University believes it) for detailed consultation. Geographic information system or geographic information system (GIS) is sometimes called "geographic information system" or "resource and environment information system". It is a specific and very important spatial information system. With the support of computer hardware and software system, it is a technical system that collects, stores, manages, calculates, analyzes, displays and describes the relevant geographical distribution data of the whole or part of the earth's surface space (including the atmosphere).

basic concept

Geographic Information System (GIS) is not only an applied engineering technology for managing and analyzing spatial data, but also an applied basic discipline spanning earth science, information science and space science. Its technical system consists of computer hardware, software and related methods and processes to support the collection, management, processing, analysis, modeling and display of spatial data, thus solving complex planning and management problems.

Geographic Information System (GIS) deals with and manages all kinds of geospatial entity data and their relationships, including spatial positioning data, graphic data, remote sensing image data, attribute data and so on. It is used to analyze and deal with various phenomena and processes distributed in a certain geographical area, and to solve complex planning, decision-making and management problems.

Through the above analysis and definition, we can put forward the following basic concepts of GIS:

1, the physical shell of geographic information system is a computerized technical system, which consists of several interrelated subsystems, such as data acquisition subsystem, data management subsystem, data processing and analysis subsystem, image processing subsystem and data product output subsystem. The quality and structure of these subsystems directly affect the hardware platform, function, efficiency, data processing mode and product output type of GIS.

2. The operating objects of 2.GIS are spatial data and attribute data, that is, geographical entities with three-dimensional elements such as points, lines, surfaces and bodies. The most fundamental feature of spatial data is that each data is coded according to unified geographical coordinates, which realizes its positioning, qualitative and quantitative description. This is the fundamental sign that GIS is different from other types of information systems, and it is also a technical difficulty.

3. The technical advantage of 3.GIS lies in its ability of data synthesis, simulation, analysis and evaluation, which can obtain important information that is difficult to obtain by conventional methods or ordinary information systems, and realize the simulation and prediction of geospatial process evolution.

4.GIS is closely related to surveying and geography. Geodetic survey, engineering survey, mine survey, cadastral survey, aerial photogrammetry and remote sensing technology provide various positioning numbers with different scales and different accuracy for spatial entities in GIS; The use of modern surveying and mapping technologies, such as electronic speedometer, GPS global positioning technology, analytic or digital photogrammetry workstation and remote sensing image processing system, can directly, quickly and automatically obtain digital information products of space targets, provide rich and more real-time information sources for GIS, and promote the development of GIS to a higher level. Geography is the theoretical support of geographic information system.