无线网络数据传输在PDA 系统中的应用

以野外林业有害生物采集系统为例,介绍了PDA通过无线网络实现移动终端与服务器之间的实时数据传输,从而可申请Google map提供的免费地图服务作为野外数据采集的调查底图,并且减少PDA存储空间的压力。无线网络数据传输技术可以将数据采集与数据处理融合在一起,提高了PDA系统的开发效率和适用范围。     

车载双目相机与惯性导航融合下的道路信息采集

为了准确快速的收集道路信息,提出了利用车载深度相机和惯性导航的信息采集方法。车辆在道路上行驶,每行驶一段距离则拍摄一张道路照片,获取图片的同时深度相机也会采集图片里每个像素的深度信息,惯性导航给出拍摄时车辆的方位角和经纬度,以车辆为起点利用公式反推所需目标像素点的经纬度坐标,从而实现对目标的定位。实验结果表明,当每20 m拍一次照片时,对平缓行驶时拍摄的车道线的定位精度小于1 m。与使用激光雷达进行定位相比优势明显,设备价格低廉易普及、数据更新速度快。该方法对于国内的道路管理和维护有着重要的作用。     

利用ExcelVBA功能实现带照片证卡的及时打印

MS Excel内置了系统开发工具VBA可以方便地调用和定制主应用程序对象,用来扩展Microsoft Office应用程序功能。本文利用Excel及其函数和VBA的简单编程功能设计了学员证卡。使学员证卡实现现场采集照片、快速打印系统。     

利用ExcelVBA功能实现带照片证卡的及时打印

MSExcel内置了系统开发工具VBA可以方便地调用和定制主应用程序对象,用来扩展Microsoft Office应用程序功能。本文利用Excel及其函数和VBA的简单编程功能设计了学员证卡。使学员证卡实现现场采集照片、快速打印系统。     

图像处理技术在考试系统中的应用

全国计算机等级考试在新的考务管理系统中增加了对考生照片信息的采集功能,本文针对这一改进,介绍了如何利用强大的图像处理软件Photoshop7.0为考生的照片信息进行加工处理的具体方法,目的是确保系统采集的照片准确、有效、不失真。     

3S技术在土地利用数据库建设和管理中的应用

以河北海兴县土地利用数据库建设和管理为例,阐述了利用RS技术获取土地利用信息,利用GPS技术开展野外调查、采集变更数据和更新数据库,利用GIS技术贯穿数据库建设和管理始终。     

3S技术在土地利用数据库建设和管理中的应用

以河北海兴县土地利用数据库建设和管理为例,阐述了利用RS技术获取土地利用信息,利用GPS技术开展野外调查、采集变更数据和更新数据库,利用GIS技术贯穿数据库建设和管理始终.     

图像处理技术在考试系统中的应用

全国计算机等级考试在新的考务管理系统中增加了对考生照片信息的采集功能，本文针对这一改进，介绍了如何利用强大的图像处理软件Photoshop7．0为考生的照片信息进行加工处理的具体方法，目的是确保系统采集的照片准确、有效、不失真。     

基于RFID智能感知摄像机的溯源系统

近年来,食品安全案件屡有发生,亟需采用透明、安全、可信的食品安全溯源系统。然而现有的溯源系统高额的视频监测储存和传输费用,限制了溯源平台的推广。设计基于RFID具备联动功能的智能感知摄像机,采用自修复机制改进基于RFID的LANDMARC定位算法,精准定位每一只牲畜的活动区域;利用联动摄像头定量采集牲畜活动信息,建立牲畜活动信息;通过GPRS将采集的照片上传到服务器,极大降低视频存储和传输成本。同时将摄像头的功耗降到最低,使其能在野外用太阳能板为系统供电。用户可以通过扫描二维码查询牲畜档案信息,极大降低绿色健康畜产品溯源成本,推动溯源系统的广泛应用。     

基于开源GIS的林业有害生物监测与预警系统

针对林业有害生物监测与预警系统建设中存在开发成本较高、开放性较差、灵活性较低等问题,提出基于开源GIS的系统架构。阐述以PostgreSQL／PostGIS为空间数据库、MapServer为GIS引擎、OpenLayers为客户端搭建据的系统平台,对多级地图缓存和基于Web Service的模型库等关键技术进行分析与描述。原型验证及工程实践结果表明,该系统具有低成本、高开放、扩展性强等特点,对于加强林业有害生物信息网络化管理和宏观科学决策具有推广应用价值。     

农作物病虫害防治管理信息系统研究开发

面向农作物病虫害防治管理工作需求,设计开发了农作物病虫害防治管理信息系统.系统将GPS、嵌入式GIS组件技术、ADOCE数据库访问技术和GIS分析管理等技术应用于农作物病虫害发生、防治信息采集和管理分析过程中,实现了农作物病虫害发生面积、发生动态、灾情损失等信息进行动态定位采集、网络化上报及动态更新、可视化分析统计、显示.初步应用表明,系统对于提高农作物病虫害信息管理水平具有较好的促进作用.     

Siberian silkmoth outbreak pattern analysis based on SPOT VEGETATION data

The spatial pattern of Siberian silkmoth outbreak in south Siberian mountains was analysed based on SPOT VEGETATION data. A digital elevation model (DEM) was also used to relate outbreak area dynamics with topographic elements (elevation, azimuth and slope steepness). To avoid bias of spatial pattern data, areas with a given damage category and with given azimuth, slope steepness and elevation were referenced to the areas with similar parameters within the entire study area. The outbreak began between the elevations of ～430–480 m and on south‐west slopes with steepness <5°; these conditions appear to be the most favourable pest habitat. As the pest searched for food it moved up and down slope, resulting in an elevation distribution split within a range of ～390–540 m and slope steepness up to 15°. In the final phase the azimuth distribution of damaged stands became even, showing that pests at this phase settle in non‐optimal habitat. The final outbreak area was ～20 000 ha, which is in good agreement with on‐ground data. The correlation between the initial phase of infestation and topographic features can be used to prioritize pest monitoring. Data obtained show that the SPOT VEGETATION sensor is applicable for monitoring taiga landscapes vulnerable to Siberian silkmoth outbreaks.     

Evaluation of LANDSAT and airborne multispectral data and aerial photographs for mapping forest features and phenomena in a part of the Godavari basin

The automatic interpretation of multispectral digital data obtained from LANDSAT as well as from an airborne multispectral scanner using an interactive computer system and visual interpretation of colour composites of LANDSAT imagery and aerial photographs of a dry deciduous forest tract were used for evaluating the discrimination capabilities of each technique and for comparative evaluation. While visual interpretation of LANDSAT imagery could give only general information, such as contiguity of vegetation cover, digital analysis of the same yielded more detailed information, such as teak-bearing and non-teak-bearing regions. The analysis of airborne multispectral data, in the present state of the art, for performing forest surveys and making maps is limited. Aerial photographs are very useful for mapping forest land features and stock, which can be done more reliably than could be done by ground surveys. Infrared photographs show better promise in mapping forest features. The integration of multitemporal data and the incorporation of digitized additional information into the data stream for the improvement of digital analysis are suggested. Acquisition of data including aerial photographs for general surveys during a period prior to leaf fall in a deciduous forest is also recommended.     

基于GIS的森林资源现状分析

以安徽省东至县梅城林场森林资源为例,以Mapinfo4.0和Viewgis2.0为GIS软件平台,建立梅城林场森林资源管理信息系统,利用该系统可以实现森林资源的准确查询、修改、统计和分析及其结果的可视化;同时可以实现森林资源的动态监测,为提高森林资源管理水平提供科学依据。     

Improving local forest volume estimates by fusion of multi-temporal forest type maps

An alternative method for estimating standing wood volume based on the fusion of multi-temporal forest type maps and single reduced associated ground-based inventories is proposed. With the integration of photo-interpreted forest map realizations from different years into a single “Fused Map” resulting in an improved local estimate of the forest type, the proposed method offers more accurate estimates than the approach traditionally used by the Quebec Ministry of Natural Resources, even with reduced ground-based inventory effort. A Fused Map is basically an adapted mean of local forest type that accounts for differences among the classification systems used for each map, temporal differences between maps, and subjectivity associated with photo-interpreted data.     

基于MapObjects的森林病虫害信息系统

分析MapObjects二次开发的特点,设计适合森林病虫害管理的地理信息系统,分析系统的部分结构、工作原理和功能。提出实现采集、处理及关联空间数据和属性数据的方法,论述系统软件部分的实现。该系统改变了森林病虫害信息管理系统的传统模式,提高了管理效率。     

Forest fire analysis with remote sensing data

Forest fires cause major damage to the environment, human health and property, and endanger life. Fires can be monitored and analysed over large areas in a timely and cost-effective manner by using satellite sensor imagery in combination with spatial analysis as provided by Geographical Information Systems (GIS). In this study, the forest area damage caused by a large fire which occurred in the Marmaris, province of Mugla in July 1996 was analysed using satellite sensor images. Digital image processing methods, such as spectral profile analysis, vegetation indices and multispectral classification, were applied to the satellite sensor images acquired before and after the forest fire. Besides the conventional maximum likelihood classification algorithm, a multilayer feed-forward neural network architecture was also used for comparison and evaluation of its effectiveness. A GIS database was constructed from the raster (satellite sensor data), vector (the forest type and topographical maps) and ancillary data (meteorological data). The GIS is being used to develop an information and decision support system to monitor and predict forest fire activity, and to enhance fire management efficiency. This study highlights the deficiencies in the current approach to fire management and emphasizes the need for an improved method along the lines outlined.     

The effects of rectification and Global Positioning System errors on satellite image-based estimates of forest area

Satellite image-based maps of forest attributes are of considerable interest and are used for multiple purposes such as international reporting by countries that have no national forest inventory and small area estimation for all countries. Construction of the maps typically entails, in part, rectifying the satellite images to a geographic coordinate system, observing ground plots whose coordinates are obtained from Global Positioning System (GPS) receivers that are calibrated to the same geographic coordinate system, and then matching ground plots to image pixels containing the centers of the ground plots. Errors in rectification and GPS coordinates cause observations of ground attributes to be associated with spectral values of incorrect pixels which, in turn, introduces classification errors into the resulting maps. The most important finding of the study is that for common magnitudes of rectification and GPS errors, as many as half the ground plots may be assigned to incorrect pixels. The effects on areal estimates obtained by aggregating class predictions for individual pixels are deviation of the estimates from their true values, erroneous confidence intervals, and incorrect inferences. Results are reported in detail for both probability-based (design-based) and model-based approaches to inference for proportion forest area using maps constructed from Landsat imagery, forest inventory plot observations and a logistic regression model.     

随机森林手势识别算法的高效嵌入式软件实现

无接触手势识别技术作为一种自然的人机交互方式,可以应用于手机、平板和可穿戴设备。为了高效实现超声手势识别嵌入式系统中采用的“一对其余”多分类随机森林算法,提出一种其推理过程的嵌入式软件实现方案。设计更精简的模型节点数据结构,以降低手势模型占用的存储空间。为节省系统能耗并缩短运行时间,利用分支定界的方法及时排除不可能产生正确解的手势类型,在保证识别率的条件下避免不必要的FLASH读取和决策树判定过程。实验结果表明,与传统的随机森林算法相比,该方案在FPGA上运行的实测时间缩短约60%,一次推理的平均判定次数低至243。