Study on Investigation and Mapping of Vegetation Landscape Distribution in the Field for Dongting Lake with Hand-held GPS;

The high-resolution position data in the centimeter grade are extracted from the binary output records of the hand-held GPS position indicator,and the multiple average measurement and post-operation position difference correction method are used so as to decrease the planar locating error of the portable and cheap hand-held GPS position indicator from several meters to 1 m or so.

Through the practice of the line selection of the water supply pipeline by using the hand-held GPS and Google earth,the paper explores the line selection method of the rapid and accurate long-distance alignment structure,points out that the technical means meets the requirement of the design and the construction,which is worth popularizing.

Application of hand-GPS in design of seismic survey;

Application of GPSMAP 276C hand-GPS in seismic exploration;

The Application of Hand-GPS in 1:50000 Stream Sediment Survey;

To solve the difficulty of replacement for fixed sample plots and the lower precision for fixed sample tree mensuration in the system of national forest resources continual inventory,the precision of inventory can be improved using portable GPS in the position of fixed sample plots,using total station to mensurate the height of fixed trees and using compass in the replacement of fixed trees.

Experimentation indicated that external accordant positioning accuracy of some portable GPS is rather too low.

The coordinate in WGS-84 system can be determined by mobile GPS conveniently and quickly.

The paper expounds the function and character of hand GPS through using the navigating type GPS315 of American Magellan Company as an example,and analyses its setting accuracy and its typical application instances in electric power engineering,as well as proposes some problems which should be noticed in hand GPS application.

Determination of the Tri-parameters of Portable GPS;

This paper introduces the character of portable GPS,and analyses its applying methods and results in engineering.

The absolutely-fixed position of CE solo point with Mobile Mapper by the instrument of portable GPS can satisfy the filling of the geological maps and geological engineering prospection over plains, hill areas, high mountain areas and other areas without blocks.