基于3G通信与GPS技术的农机视频监控系统研究

针对现代化大农机发展的需求,研究了如何将3G通信技术与GPS定位技术相结合,建立农机视频监控系统,用于现代化大农机管理。采用WebGIS技术为基础,以B/S结构进行开发建设,为农机综合管理监控提供了新思路、新手段。     

一种新的载波相位观测量计算方法与实现

载波相位测量主要完成载波相位整周模糊度的估算,不足一周的小数部分的测量以及载波相位的变化.针对目前载波锁定后的载波相位观测量的计算问题,在已知整周模糊度的基础上提出了一种计算载波相位观测量的方法,与传统方法相比较,在测量精度不变的情况下,其软硬件实现更为简单.     

Integrating space and time: a case for phenological context in grazing studies and management

In water-limited landscapes, patterns in primary production are highly variable across space and time. Livestock grazing is a common agricultural practice worldwide and a concern is localized overuse of specific pasture resources that can exacerbate grass losses and soil erosion. On a research ranch in New Mexico with average annual rainfall of 217 mm, we demonstrate with a quantitative approach that annual seasons vary greatly and examine foraging patterns in Angus-Hereford (Bos taurus) cows. We define five seasonal stages based on MODIS NDVI: pre-greenup, greenup, peak green, drydown and dormant, and examine livestock movements in 2008. Daily distance traveled by cows was greater and foraging area expanded during periods with higher precipitation. A regression model including minimum NDVI, rainfall and their interaction explained 81% of the seasonal variation in distance traveled by cows (P<0.01). Cows explored about 81 ha·d⁻¹ while foraging, but tended to explore smaller areas as the pasture became greener (greenup and peak green stages). Cows foraged an average of 9.7 h daily and spent more time foraging with more concentrated search patterns as pastures became greener. Our findings suggest that phenological context can expand the capacity to compare and integrate findings, and facilitate meta-analyses of grazing studies conducted at different locations and times of year.     

GPS在沿海围垦动态监测中的应用

采用Ｍａｇｅｌｌａｎ ＰｏｒＭＡＲＫ Ｘ－ＣＭ手持ＧＰＳ接收机,以广东省湛江市通明海海为实验区,通过野外实地数据采集、室内数据差分后处理、与ＴＭ影像准等,探索了一套ＧＰＳ与遥感图像分析相结合、快速、准确析沿海围垦动态数据的工作流程。结果表明：ＧＰＳ应用于ＴＭ影像几何纠正,可提高ＴＭ影像几何纠正的精度,ＧＰＳ采集的数据可以辅助目视解译,提高目视解译精度：ＧＰＳ可以补充ＴＭ影像成像后最新的动态信息。     

现代大规模农业机械化将使东北农村粮食生产产生巨变的认识

黑龙江省2010年由私人投资、政府贴补购机,在农村将筹建440个农机专业合作社,配备了现代化的180～483马力的拖拉机与大型农业机械装备,每个合作社的服务面积为1 330～3 330hm2.由于生产率显著增高,作业的适时性、精准度也随之提高.粮食的单产与总产将将大幅度增加.作物的耕作栽培模式亦需作某些相应的改变.建立...     

基于互联网的GPS定位、跟踪、预警系统在森林管护中的应佑

研究和构建分布式GPS定位、跟踪、预警信息服务平台,通过构建统一的信息服务平台,实现了基于GPS应用的数据采集、统计、分析和数据共享,为用户提供统一的交互平台,从而将多行业、多业务不同类型、不同操作流程的GPS相关应用整合到统一平台,统一身份认证、数据中心,实现统一信息平台下的多业务数据信息服务平台,并重点阐述了本系统在森林管护中的具体应用.论述了系统结构的设计、管理平台设计方法以及如何采集GPS等数据,实现GPS定位、跟踪、预警的功能等.该系统结合GPS、GIS,以及GSM、GPRS等技术实现了动态跟踪与轨迹回放,弥补了传统方法的不足,从而充分提高了管理者的工作效率.     

手持GPS测量面积的精度分析

介绍了手持GPS在森林资源调查、工程造林中林地面积测量的精度,选择已知面积作为测量对象,对测量误差及其精度进行分析计算,结果表明:手持GPS测量林地面积的精度能够满足林业中的应用要求.     

Wireless tracking of cotton modules. Part 2: Automatic machine identification and system testing

The ability to map profit across a cotton field would enable producers to determine where money is being made or lost on their farms and to implement precise field management practices to facilitate the highest return possible on each portion of a field. Mapping profit requires knowledge of site-specific costs and revenues, including yield and price. Price varies site-specifically because fiber quality varies, so mapping fiber quality is an important component of profit mapping. To map fiber quality, the harvest location of individual cotton bales must be known, and thus a system to track the harvest location of cotton modules must be available. To this end, a wireless module-tracking system was recently developed, but automation of the system is required before it will find practical use on the farm. In Part 1 of this report, research to develop automatic triggering of wireless messages is described. In Part 2, research to enable the system to function with multiple harvesting machines of the same type in the same field - a common situation in commercial cotton farming - is described along with testing of the entire automated wireless module-tracking system (WMTS). An RFID system was incorporated, and it enabled the WMTS to correctly and consistently differentiate among various harvesting vehicles. The improved WMTS subsequently sent wireless messages to the correct machines when cotton transfers were made in the presence of multiple harvest machines. Overall testing proved that the automated WMTS worked largely as designed. When both complete and partial cotton basket dumps were simulated, the correct wireless-messaging decision was made 100% of the time.     

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。     

基于嵌入式GIS的森林资源三类调查数据采集及处理系统设计

介绍一种集成嵌入式GIS、GPS和PDA的森林资源三类调查系统的设计和实现,对系统的总体框架、功能设计以及软件开发实现中的几个关键问题进行了阐述．该系统克服了传统手工采集方法的诸多弊端．实现了三类调查的自动化和无纸化．应用结果表明,采用该系统可以大幅度地提高三类调查的精度和效率．