高精度边角网数据采集与处理系统的设计与实现

在水利、桥隧等工程施工和形变监测中,特别是在山区,GPS网的精度往往不能满足设计要求,一般需要布设地面边角网,采用高精度智能型全站仪进行数据的采集。本文从一体化测量作业模式的设计思想出发,基于VB．NET和数据库技术,研究设计了高精度地面边角网外业数据采集与处理系统,实现了边角数据的自动化采集和处理。     

变形监测数据自动检查程序开发

在大型工程的变形监测中,传统方法是利用全站仪,按照等级测量规范进行方向法、全圆法观测,测站至少需要1个观测员、1个记录员,每个测回需要人工计算和比较,内业需要后处理,费工、费时、容易出错。结合测绘实践的现实需要,利用VB语言和TCA2003全站仪的内置程序功能,开发变形监测数据自动检查程序,为自动化测绘探索新的方法。     

基于移动测量的交通标志自动提取

针对从移动测量车采集的图像中提取交通标志的需求,研究探索适合移动测量的交通标志检测识别方案。在交通标志检测阶段,提出一种检测多个圆形禁令标志连接的多圆度检测法,对于三角形警告标志的检测,在原有拐角检测法基础上提出基于候选区域的拐角检测法;在交通标志识别阶段,选用像素特征作为特征向量,采用概率神经网络实现交通标志的分类识别。最后设计实现移动测量后处理软件的交通标志自动提取模块。     

基于嵌入式开发的便携式水域测量系统

基于水下地形测量原理,通过设计全新的船体结构和双动力系统,加载船载的GPS RTK和测深仪,完成了测量船的基本制造装配。通过开发岸基控制模块自动导航软件及基于嵌入式的船载控制模块,实现了遥控测量船的水下地形数据采集和远程控制功能。     

信息监理在地铁结构自动化监测系统中的应用

从地铁结构自动化监测系统的体系架构和功能特点出发,引出本项目信息监理工作的难点,并从感知层、网络层和应用层剖析监理工作的重点。以组织、制度和规范等保障措施,用现场旁站、专家评审和测试等主要监理方法来保证信息系统全面和多学科交叉的地铁结构自动化监测系统监理工作质量。     

基于bat和vbs的Oracle属性数据和ArcSDE空间数据自动备份技术

数据库自动备份功能的实现大都是制作一个工具在Windows任务里定时执行,而工具的制作则多种多样,可以使用高级语言开发平台编写,也可以使用脚本写成批命令执行。常规的是开发一个自动备份工具,这样做有一定的开发量,且需要依赖某些部署环境。本文介绍在Windows平台下,如何仅通过dos命令和vbs脚本完成Oracle属性数据和ArcSDE空间数据的自动备份功能。     

“全站仪、GPS RTK测量纵横断面软件”的开发与应用

本软件为全站仪、GPS RTK数字化测量纵横断面实现数据后处理,可以方便、快速、准确地将测量数据转换成成图软件所需要的数据格式,极大地提高了内业的工作效率,在实际工作中取得了明显的经济效益。     

Measurement of the radial density gradient of cosmic ray in the heliosphere by the GRAPES-3 experiment

A radial anisotropy in the flux of cosmic rays in heliosphere was theoretically predicted by Parker and others within the framework of the diffusion–convection mechanism. The solar wind is responsible for sweeping out the galactic cosmic rays, creating a radial density gradient within the heliosphere. This gradient coupled with the interplanetary magnetic field induces a flow of charged particles perpendicular to the ecliptic plane which was measured and correctly explained by Swinson, and is hereafter referred as ‘Swinson flow’. The large area GRAPES-3 tracking muon telescope offers a powerful probe to measure the Swinson flow and the underlying radial density gradient of the galactic cosmic rays at a relatively high rigidity of ∼100 GV. The GRAPES-3 data collected over a period of six years (2000–2005) were analyzed and the amplitude of the Swinson flow was estimated to be (0.0644 ± 0.0008)% of cosmic ray flux which was an ∼80σ effect. The phase of the maximum flow was at a sidereal time of (17.70 ± 0.05) h which was 18 min earlier than the expected value of 18 h. This small 18 min phase difference had a significance of ∼6σ indicating the inherent precision of the GRAPES-3 measurement. The radial density gradient of the galactic cosmic rays at a median rigidity of 77 GV was found to be 0.65% AU⁻¹.     

Comparison of genetic algorithms and shuffled complex evolution approach for calibrating distributed rainfall–runoff model

Three methods, Shuffled Complex Evolution (SCE), Simple Genetic Algorithm (SGA) and Micro‐Genetic Algorithm (µGA), are applied in parameter calibration of a grid‐based distributed rainfall–runoff model (GBDM) and compared by their performances. Ten and four historical storm events in the Yan‐Shui Creek catchment, Taiwan, provide the database for model calibration and verification, respectively. The study reveals that the SCE, SGA and µGA have close calibration results, and none of them are superior with respect to all the performance measures, i.e. the errors of time to peak, peak discharge and the total runoff volume, etc. The performances of the GBDM for the verification events are slightly worse than those in the calibration events, but still quite satisfactory. Among the three methods, the SCE seems to be more robust than the other two approaches because of the smallest influence of different initial random number seeds on calibrated model parameters, and has the best performance of verification with a relatively small number of calibration events. Copyright © 2009 John Wiley & Sons, Ltd.