浅谈GPS在公路线路控制测量中的应用

目前,在中、高等级的道路控制测量中已广泛使用全球定位系统(GPS)。该控制测量方法能使工作效率和控制测量精度大大提高。GPS在公路工程测量中主要应用于路线平面控制点布设和路线平面控制网的布设等方面。     

GPS技术在林业工作中的使用技巧

<正>GPS这一先进的测量仪器已越来越多地被广泛应用于各个领域,近年来,GPS已普遍应用于各项林业工作中。为高效、准确完成林业测量工作发挥了其独特的重要作用。掌握GPS的使用技巧,结合林业工作的实际情况,可以更好地发挥它的优越性。1使用前的准备(1)了解所使用的GPS内置的测量系统,然后设置成     

GPS-RTK技术在水下地形测量中的应用

本文主要阐述GPS-RTK技术在水下地形测量中的实际运用。随着GPS技术的飞速发展，水下地形测量技术已定型于采用GPS获得平面坐标，测深仪获得深度数据的基本模式。对GPS-RTK的原理、作业方法及与测深仪操作流程中遇到的问题和解决方法进行了详细介绍。     

GPS-RTK技术在水下地形测量中的应用

本文主要阐述GPS-RTK技术在水下地形测量中的实际运用.随着GPS技术的飞速发展,水下地形测量技术已定型于采用GPS获得平面坐标,测深仪获得深度数据的基本模式.对GPS-RTK的原理、作业方法及与测深仪操作流程中遇到的问题和解决方法进行了详细介绍.     

GPS卫星测量在公路勘测中的应用

对GPS卫星测量的基准、原理、作业方法、GPS接收机及GPS测量局限性作了介绍，详细叙述了GPS卫星测量在公路勘测中的应用及存在的问题。     

GPS术语及主要应用方法

数字林业是我国林业的发展方向,GPS已逐步进入我们林业日常经营管理,文章简要的介绍了GPS中常用的术语,并同时介绍了其在森林调查中自动向导、方位测量、野外寻址、区划面积等方面的主要应用。     

GPS72在面积测量中的应用技巧

手持GPS接收机是海南省林业系统目前主要的面积测量工具,在林业规划设计、检查验收中广泛应用。以GPS72为例,简述GPS在面积测量中一些方法,通过对不同方法所测量的面积进行对比,分析影响面积测量精度的因素,总结出提高面积测量精度的方法。     

全球定位系统（GPS）及其在林业方面应用

航天技术的发展已在测量领域中得到了广泛的应用,诸如卫星大地测量与遥感技术的出现已经使测量技术发生了巨大的变化。GPS(全球定位系统)已经成为国际测量界的热门话题,在我国同样也引起了广泛的关注。笔者认为随着时间的推移,GPS 定位将扩展到更多的领域。预计今后在林业系统中也将得以广泛的应用和发展。     

沙漠地区GPS精度分析

介绍了GPS在沙漠地区资源调查、工程造林中地块测量的精度,选择已知地物作为测量对象,对测量误差及其精度进行分析计算,结果表明:GPS测量在沙漠地区资源调查、工程造林中林地测量精度不能完全满足林业中的应用要求,同时对GPS在实际应用中应注意的问题提出建议。     

GPS定位技术在森林公园道路平面控制测量的应用

本文对GPS的工作原理和定位技术进行介绍，通过东莞市大岭山森林公园道路的控制测量实例介绍了静态GPS测量和实时动态RTKGPS测量，比较了GPS测量和传统测量方法的优劣，并提出GPS测量在公路勘测设计中的发展应用。     

Measuring tree-ring increments on tree bole sections with a video-based robotic positioner

We report on the design and performance of a system that speeds measurement of radial tree-ring increments on tree stem disks; this method replaces the usual binocular microscope with a video image, and automates the measuring and recording processes. The system was used to measure bole sections cut from stems at various heights to determine volume growth of representative trees in an old-growth ponderosa pine stand. The objective of the measurement system was to speed acquisition of annual growth increments from a large number of disks. A personal computer controls the location of a video camera in a 3-axis positioning system. The operator views the sample on a video monitor and positions the camera over each ring by selecting it with a computer-driven mouse. The computer measures and records the distance that the camera moves between each ring. Task selection is facilitated by menu-driven software that also formats, checks and organizes data files. Measurements have a resolution of 0.026 mm; however, finer resolution could be obtained with a different camera lens. Tests of measurement variability (repeated measurements by individual operators on a single radius) indicated standard errors of 0.006 mm or less for the first measurement sets for four operators. Correlation coefficients among four radii per bole section were as low as 0.66 for a whole tree, suggesting that measurements on single radii may provide poor estimates of radial growth for old trees. This system also offers the potential for automatic ring detection and measurement.     

基于声信号的供气管道阀门泄漏监测与定位系统研究

对供气管道阀门泄漏监测与定位系统进行基于声信号的研究,结合GPRS/GSM网络平台的长距离传输方式设计出可实现定位反馈功能的系统架构模型。文中详述系统的组成及内部连接方式并对传感器固定装置进行设计,利用不同材质管道泄漏孔声信号频率分析表设计出系统运行过程框图。系统应用的自动化监测模式对管道阀门泄漏监测与定位起重要意义。     

基于双目立体视觉SLAM的林下实时定位

[目的]在林下环境中受到树木冠层的遮挡,易造成全球导航卫星系统卫星信号失锁,不能满足林下实时定位的需求.本研究引入双目立体视觉SLAM技术,在移动过程中根据周围环境中路标点的位置变化实时确定传感器的空间位置和姿态,以期在林下环境中达到实时定位的目的.[方法]实验过程中使用双目相机按照10 Hz的采集频率对3块边长为40...     

基于ZigBee井下人员定位系统的节点错位布置方法

提出了参考节点错位布置的方法，采用基于ZigBee技术的矿井人员定位系统，将参考节点交错布置在矿井的两侧，从井下人员携带的移动节点获取参考节点的RSSI信号，通过定位算法得到井下移动人员的位置。分析了ZigBee技术的矿井人员定位系统的组成，给出了参考节点错位布置的方法，通过了定位仿真实验，结果得到了井下目标的定位及其误差，基于错位布置参考节点的定位系统将节约定位系统的成本。     

青海云杉天然次生林区DGPS定位精度分析

黑河综合遥感联合试验是针对地球表层系统科学中存在的科学问题而开展的大型观测试验,其中森林水文试验区位于祁连山水源涵养林大野口生态站,森林类型为青海云杉天然次生林。为了对同步获取的航空—卫星遥感观测数据与地面观测数据进行位置匹配,采用DGPS和全站仪分别进行独立观测,以全站仪观测结果作为参考数据,对DGPS在林地内的定位精度进行分析与评价。结果表明,单频和双频差分处理精度类似,观测时卫星数和PDOP不能反映定位精度,影响定位精度的主要因素是林分郁闭情况,定位精度从亚米级变化到米级。     

多雷林区冷云催化防雷作业系统

介绍一种针对森林草原等开阔空间的大面积防雷系统。该系统将雷达探测技术、早期雷暴定位技术、人工影响闪电及催化消雷火箭作业技术有机地集成在一起并使之工程化,可为森林防护规划提供借鉴。     

Reliability of GPS/GNSS-based positioning in a forestry environment

The critical environment is one of the main insufficient to positioning. Geodetic observing systems such as the global positioning system (GPS) and the global navigation satellite systems (GNSS) are routinely used to estimate the contaminating effects by critical environment. In an effort to define the accuracy and reliability of GPS/GNSS positioning, we investigated the data having contaminating effects due to forestry environment. Some reliability criteria and geometric concepts were defined and then examined by them. Two sets of data were collected in open sky and closed canopy separately. The analysis of the observed data was performed using the reliability criteria and geometric concepts. The accuracy and reliability of positioning strongly depended on the canopy ratio and satellite availability. The minimum detectable error on baseline was estimated about 2.5 mm under closed canopy. The number of observable satellites and minimal detectable errors were computed for each epoch. The minimal biases on estimated baselines, bias-to-noise ratios for estimating baseline components and probability of success of the integer ambiguity solution were defined in case of forest canopy. Finally, geometric quality could be achieved using the factors of dilution of precision. Thus, the presented accuracy and reliability concepts fulfill the requirement proposed by the global geodetic observing system in forest environment.     

奥维互动地图在林业工作中的应用探析

随着信息技术的不断发展,奥维互动地图类软件在林业工作中被广泛应用,其不仅为林业工作开展带来较大便利,也在一定程度上提升了林业工作效率,帮助林业工作开展解决了实际成本。文中介绍了奥维互动地图的功能和常规设置,阐述了其在林业经营与管护工作、森林资源调查与连续清查、征占用林地调查和林业综合规划中的应用;对奥维互动地图在应用中存在的定位系统稳定性差、影像更新速度较慢、软件使用要求高、专业性比较单一等不足;提出提高定位稳定性、开发林业应用插件等建议。     

Accurate single-tree positions from a harvester: a test of two global satellite-based positioning systems

Accurate positioning of single trees registered automatically during harvesting operations opens up new possibilities for reducing the field sampling effort in forest inventories utilising remotely sensed data. In the present study, we propose to use a harvester to collect single-tree data during regular harvest operations and use these data to substitute or supplement traditional measurements on sample plots. Today’s harvesters are capable of recording single-tree information such as species and diameter at breast height, and a cut-to-length harvester was equipped with an integrated accurate positioning system based on real-time kinematic global satellite positioning, as well as a low-cost global navigation satellite system (GNSS) receiver mounted directly on the harvester head. Positions from 73 trees were evaluated and compared to coordinates obtained using a total station. At the single-tree level, the mean error for the integrated positioning system was 0.94?m. The low-cost GNSS receiver mounted on the harvester head yielded a mean error of 7.00?m. The sub-meter accuracy obtained with the integrated system suggests that data acquired with a harvester using this positioning system may have a great potential as a method for single-tree field data acquisition.     

林业工作中GPS功能简介

简单叙述了林业工作者在野外工作中,GPS全球定位系统导航仪所具有的定位、测距、测速、导向和卫星示踪等功能。