Research On Optimization Application Of Data Structure Processing Of Geographic Information

In modern information society, it's shortening communication distance and geographic barrier between people as rapidly developing of network communication, traffic transportation, information processing technology and etc. People living in this small Earth village can feel timely important events happening from various places around global earth and its social influence, as a result, it seems that the earth goes smaller. At the same time, as developing of computer technique, Observe on Earth, GPS, Internet and etc., amount of information is getting much more than ever, which makes people enter era of information explosion without knowing whence and whither. It makes people have a better way for categorizing various kind of information by Geographic Information Infrastructure, Digital Earth, or Global Information Grid. Through advanced application system like Digital Earth or Global Information Grid, people can feeling easily and directly pulse of developing and changing of the earth, and can search easily any social information, which you want to know, accumulated by human civilization.Starting from analyzing vector and raster data structure most simplified in geographic information infrastructure, this dissertation advances optimize applying thought about mutually converting between vector data and raster data. Area constrained vector to raster converting method is then advanced suiting for trades strict in polygons'area. Experiment shows that: Error value of area of any polygon in conversion results is constrained below value of single grid area, which improves result data precision dramatically.Method for determining best parameter value based on maximum curvature value of fit curve is advanced in this dissertation for vector geographic data simplification, which objective balances between simplifying with accuracy, and find a good way objective determining parameter value of huge geographic data simplification; In view of highly length claim like traffic, optimize line simplifying method constrained by line length, which is called turn angle, is advanced based on current simplifying methods by taking out points from line. Test shows that: This optimize reduces change value of line length and improves accuracy of data applying.With on-the-fly smoothing method and visual principle, this dissertation optimizes line multi scale expression by way of improving effects of large scale visualizing and of determining extents of line visualizing, which makes multi scale expression of vector line confirm to nature principle.At last, it is put forward for establishing traffic basic information processing prototype and correspondingly applying optimize method. Main contributions of this dissertation include:1) New optimize method of vector data converting to raster data constrained by area value;2) New optimize method of determining best parameter value based on maximum curvature of fit curve;3) New method of line simplifying constrained by line length;4) Optimize expressing of vector line multi scale with on-the-fly smoothing and visual principle;5) Optimize application on traffic basic information processing prototype.