数字地图更新的伪立体法

为了有效地更新数字地图,作者设计了\     

遥感影像变化检测在地形图快速修测中的应用

首先介绍地形网修测中常规判读地物地貌发生变化的方法,以及将变化检测技术应用于地形图修测中的必要性;其次介绍变化检测的基本原理、发展历史、国内外对变化检测概念的不同定义以及变化检测技术的特点和应用范围;紧接着从地形图快速修测这一客观需要出发,简明扼要地叙述变化检测方法的选择、变化检测的一般过程、变化检测结果在地形图修测中的应用,并结合变化检测的精度评估公式分析将变化检测技术应用于地形图修测工作中的实际效率;最后展望变化检测技术在地形图快速修测中的应用前景。     

基于JX4数字摄影测量工作站的地理信息数据库直接更新的方法设计

针对目前地理信息数据库更新中普遍存在着数据转换和数据管理上的问题,提出将ArcGIS作为数据采集及编辑平台,用JX4数字摄影测量工作站进行地理信息数据库更新的方法,并采用COM技术编程加以实现。实验表明,利用此方法,可以大大减少数据更新的工作量,提高工作效率。     

基于数字摄影测量工作站的1：10000地形图更新

结合1：10000 DLG更新的实际,提出了一种基于数字摄影测量工作站的地形图矢量要素更新模式,即充分利用现有的DLG与DEM数据及各要素之间的空间位置关系,将二维表达的矢量要素转换到三维立体空间,进而在数字摄影测量工作站立体环境中进行修侧与新旧数据接边,它既能得到与数字摄影测量立体测图质量一致的成果,且充分利用了现有的DLG成果,达到节约作业成本、缩短作业周期、减少作业工作量的效果。实验表明,本方法具有可行性、可操作性。     

利用 LiDAR 点云提取有地形约束的光滑海岸线

针对传统海岸线提取算法误差大、在地形突变区域形变大的缺点,提出了一种基于离散 LiDAR 点云提取有地形约束海岸线的方法.首先,通过离散点云构建约束三角网,减少内插规则格网的误差并且保证海岸线不穿越地形结构;其次,进行顾及地形结构的点云高程修正,在数据源上缓解海岸线的平滑问题;最后采取二次多项式法消除毛刺,利用动态阈值张力样条函数内插生成光滑海岸线.     

基于GIS技术的征地统一年产值标准测算方法

合理的征地统一年产值标准的测算方法是完善征地补偿机制和保护农民土地权益的基础和保障.通过遴选出具有代表性的修正因素和构建GIS空间聚类模型来优化修正和相关测算,并采用基于GIS的图、数、库一体化的数据组织方法,实现了征地统一年产值标准测算.测算结果体现了征地补偿的空间分布及差异规律,为征地统一年产值标准测算提供了新的思...     

INSTRUMENTAL REQUIREMENTS FOR MODERN MAP REVISION

An examination of the need for map revision and the methods currently used allows the identification of problems specific to this operation. It is suggested that many instruments, old and new, suitable for new map production do not solve the problems associated with map revision. The main characteristics of instruments designed for map revision in the future are outlined, with the suggestion that the time has now come for instruments to be designed specifically for the map revision task, rather than practitioners having to devise revision procedures to suit existing equipment.     

ORTHOPHOTOGRAPHY FOR RURAL MAP REVISION

The Ordnance Survey (OS) has recently investigated the potential of orthophotography for revision of 1:2500 scale mapping following advances in technology since an earlier investigation in 1973. The results have been compared with stereoplotting on an automated workstation. The background to the investigation and the existing revision methods used for rural areas are described. Orthophotography was produced on a Zeiss 22 Orthocomp at 1:2500 scale using digital height model data supplied from contours (at a 5 m vertical interval) on 1:10000 scale mapping. A pilot block of 20 km² was revised at Kingsbridge, south Devon to assess three levels of revision (local fit, part remedial, and full remedial), using three techniques (orthophotograph overlay, Stereo-orthophoto Plotter and stereoplotting instrument). The quality of the image of the orthophotographs was below that expected for rectified enlargements and the cost of orthophotograph production made the technique uneconomic compared with existing techniques. Orthophotographs were capable of improving the accuracy of revision mapping, but the most cost effective and accurate method was full remedial revision using a Kern PG2 automated workstation.     

Use of an inside buffer method to extract the extent of urban areas from DMSP/OLS nighttime light data in North China

Defense Meteorological Satellite Program (DMSP)/Operational Linescan System (OLS) nighttime imagery provides a valuable data source for mapping urban areas. However, the spatial extents of large cities are often overestimated because of the effect of over-glow from nighttime light if a fixed thresholding technique is used. In the work reported here, an inside buffer method was developed to solve this issue. The method is based on the fact that the area overestimated is proportional to the extent of the lit area if a fixed threshold is used to extract urban areas in a region/county. Using this method, the extents of urban areas in North China were extracted and validated by interpretations from Landsat Thematic Mapper images. The results showed that the lit areas had a significant linear relationship with the urban areas for 120 representative cities in North China in 2000, with an R² value of over 0.95. This demonstrates that the inside buffer method can be used to extract urban areas. The validation results showed that the inside buffer model developed in 2000 can be directly used to extract the extent of urban areas using more recent nighttime light imagery. This is of great value for the timely updating of urban area databases in large regions or countries.     

ORDNANCE SURVEY EXPERIENCE WITH PHOTOGRAPHY FROM SPACE

The Ordnance Survey of Great Britain (OS) is a Principal Investigator for the Metric Camera experiment being organised by the European Space Agency (ESA). Two investigations are being conducted by the OS, both concerned with the potential value of the photography for topographic mapping and map revision. The first relates to Great Britain and the second relates to the developing countries of the world. Neither of these investigations is complete and only interim results and conclusions can be presented.     

地形变化调查统计方法的研究

本文针对地形变化情况,提出了地形变化调查内容;从理论和试验评价了统计方法,认为格网统计法能客观反映地物年变率;提出了更新周期计算公式,建立了地物年度率与更新周期的关系。     

土地利用更新调查的技术路线

介绍了三种土地利用更新调查工作所采用的技术方法,分析了采用不同的技术方法所表现出的工效效应,并指出了其首选技术方法。     

基于天绘卫星融合影像的地形图修测技术探讨

基于天绘卫星融合影像修测1∶50 000地形图的工作已经大面积开展,本文介绍了利用天绘卫星融合影像进行地形图修测的作业方法,结合工作实际,对修测中常见的问题进行分析,并对提高修测成果质量提出几点建议,供大家参考。     

无DEM支持的遥感正射影像制作

提出并发展了一套无需ＤＥＭ支持的遥感正射 影像制作方法,包括平坦地区多项式选点整体纠正法、中等超伏地区图形图像局部自适应迭代配准纠正以及大倾斜影像或高山起伏是区基于偏差量算的逐点纠正法。该方法仅需地形 扫描纠正开成的数字栅格地形图（ＤＲＧ）的支持,已通过大量的试验验证并已形成可供实用的软件系统。     

Monitoring the evolution of irrigated areas with Landsat images using backward and forward change detection analysis in the Kou watershed,Burkina Faso

The Kou watershed is characterized by important water resources used for drinking, agriculture (especially in the irrigated areas), industry and the preservation of aquatic fauna and flora. For several decades, there has been increasing pressure on the Kou's water resources, partly because of the expansion of the irrigated agricultural areas. This study was conducted to examine this issue, focusing on one specific irrigated area. In order to monitor the expansion of irrigated areas in developing countries, a low-cost remote sensing method based on Landsat images and aerial photographs was developed. The method is based on maximum-likelihood classification, followed by backward and forward change detection analysis requiring agronomic expertise. Using pixel trajectory analysis, the method connects all pixels to their consecutive states in order to correct their current states. The study showed that the irrigated area has expanded by almost 70% over 20 years, with most of this expansion occurring in the past 10 years. The method, if validated, could be used to obtain better information on past occupation in the rural irrigated areas for which there is currently no archived data, making temporal analyses impossible.     

高速铁路CPⅢ高程控制网测量方法研究

本文分析高速铁路CPⅢ高程控制网建网时普遍采用的德国测量方法,指出其存在的不足,在此基础上提出了技术上更为合理又适合我国国情的矩形法测量方法。通过对矩形法相邻点高差相对中误差和最弱点高程中误差的估算以及实验验证,认为矩形法可以用于CPⅢ高程网的建网测量。研究结果对于目前高速铁路工程测量相关规范的制订和在建高速铁路CPⅢ高程网的测量具有重要的参照价值。     

基于复杂网络的国际农产品贸易分析

本文基于2001~2016年国际农产品贸易数据,采用复杂网络分析方法,评估各国在贸易网络中的地位,并借助QAP相关分析(Quadratic Assignment Procedure)探究国际农产品贸易网络结构的影响因素。研究结果表明:2001~2016年综合中心性排名前10的国家整体格局未发生剧烈变化,且大多为发达国家,美国、中国、德国位居前列;国家间的GDP、人口、国土面积、农业用地面积和外商直接投资的差异与全球农产品贸易显著正相关,而距离、收入差距对其有负向影响。     

中国-巴西地球资源卫星(CBERS)计划

中国和巴西两国空间技术合作计划是发展中国家之间在高技术领域的第一个合作计划。它的目标是在互利和各负其责的基础上发展空间技术。本文将叙述这颗具有独特多传感器载荷能力卫星(CBERS)的主要特点。卫星携带有3种成像传感器,具有同类卫星所没有的某些新特点。文中讨论了传感器的设计技术和成像仪的性能特点。并简要介绍以后将继续设计和建设的与应用和用户需求相适应的地面部分处理应用系统。     

泉港区土地利用更新调查技术方法研究

土地利用更新调查是新形势下加强土地资源管理的一项新任务，本文通过介绍福建省泉港区土地利用更新调查的技术路线与方法，分析了采用该方法获得的调查结果，为泉港区的土地资源合理利用、规划和科学管理提出了有效的建议。     

A REVIEW OF MAP REVISION BY PHOTOGRAMMETRY

Revision has become a task equally as important as new mapping. Photogrammetric methods, however, have developed around the latter rather than the former. Modern instrumentation rejects this growth process. This paper examines the efficacy of various photogrammetric approaches for revision with respect to both detection and plotting of change.