Analysis on accuracy of Engineering Star RTK in cadastral survey based on SOUTH-CORS

Currently,with the fast development of GPS technique,GPS RTK is rapidly being applied to the cadastral survey.GPS RTK technique not only improves efficiency and accelerates the rate of mapping,but also increases economic efficiency.The authors introduced a method for GPS RTK rapid positioning,which uses continuous operational reference system (CORS) as a base station to change the method of previous map drawing by obtaining real-time three-dimensional coordinates of boundary points and statistically analyzing with the three-dimensional coordinates obtained by Total Station to get the accuracy of GPS RTK real-time coordinates.The application of GPS RTK in practical measurement was discussed when the data link had been lost especially.The results show that the three-dimensional coordinates measured by total station can be replaced by real-time three-dimensional coordinates measured by Engineering Star RTK in the CORS.     

地籍信息系统数据库的构建

从地籍信息系统数据库的结构、管理、使用与维护等方面,提出了建立地籍信息系统数据库的基本要求。介绍了建立地籍信息系统数据库的方法。并分别对数据采集的方法、地籍数据的分层分类与编码、数据库的结构设计方案等一系列关键的技术要点进行了详细的探讨,阐述了在本项目开发过程中,一些所遇问题的解决方案,并总结了项目开发的实际经验。     

试论适合叠合盆地的油源对比方法

应用谱图形态、碳同位素分布、生标参数和多元统计法，对叠合盆地的油源对比研究进行了分析对比，发现谱图直接对比，虽简单明了，但叠合盆地的成藏特征会使得一些不具成因联系的样品具相似谱图，或有成因联系的样品谱图差别却较大；碳同位素分布亦较直观，但分馏效应使得判别时偏离值不易把握；生标参数虽具成因意义，但受多因素影响；生标参数组合能同时全面反映各控制因素；分段成熟度可以有效地判识混源油；多元统计法既能处理大量样品又能清楚界定相关性。结果表明，多因素生标参数组合、分段成熟度和多元统计法是适合于叠合盆地油源对比的有效方法。     

A method for the removal of ray refraction effects in multibeam echo sounder systems

To a multibeam echo sounder system (MBES), under water sound refraction plays an important role in depth measure-ment accuracy, and errors in sound velocity profile lead to inaccuracies in the measured depth (especially for outer beams). A method is developed to estimate the sound velocity profile based on the depth measured by vertical beam. Using this depth and other pa-rameters, such as t (sound pulse propagation time), 0 (beam inclination angle), etc. We can estimate a simple sound velocity profile with which the depth error has been reduced. This method has been tested with a real dataset acquired in the East China Sea.     

地下水系统平衡化学模型的研究现状及发展方向

在对地下水系统平衡化学模型的类型及其主要功能进行介绍的基础上，论述了平衡化学模型在国内外的研究现状，对平衡化学模型应用的局限性进行了讨论，阐述了目前在地下水系统平衡化学模型研究中所存在的问题，指出了今后的发展方向。