跨时空观下的遥感应用新视野

遥感是一门应用性极强的现代地球信息学科,在总结分析遥感学科理论发展与遥感应用新特征基础上,进行遥感学科发展与应用理论探索,是推动遥感学科与应用迈上新台阶的重要任务。本文通过对现有遥感学科组成及分类体系的分析,首先提出了一种基于方法论的遥感学科分类新方法,在分析遥感应用中普遍存在的跨时空特征基础上,从遥感应用新视野提出了跨时空遥感的理论,最后结合典型案例剖析了跨时空遥感的应用。跨时空遥感理论的建立顺应遥感学科发展的需要,遥感应用时空观的提出对今后遥感应用具有参考价值。     

无人机遥感技术制作 DEM 新方法

无人机遥感技术能够快速制作地表模型DSM ,由于测区地物的存在,地表模型不能替代DEM ,本文提出利用激光点云处理软件 Terrasolid软件,通过高程分类算法对点云数据进行分类,通过人机互助快速提取出地面点制作DEM 。     

基于Levenberg-Marquardt法的中国大陆地区地震烈度分布快速评估的偏差特性分析

地震灾害发生后,可根据地震烈度衰减关系,利用地震灾害快速评估系统初步评估烈度分布范围。为评定烈度分布结果的偏差特性,利用中国西部地区488个震例和中国东部地区182个震例的等震线数据,使用Levenberg-Marquardt非线性迭代算法进行回归,计算我国大陆分区域烈度衰减关系,并对中国大陆1990—2007年23次6.0级以上地震以及2008—2019年88次5.0级以上地震进行烈度评估。结果发现,应用本研究所得烈度衰减关系进行烈度评估,不同烈度区分布面积与实际震害面积存在一定偏差,体现在:①高烈度区:实际震害面积往往比模型面积偏大;②低烈度区:实际震害面积往往比模型面积偏小。据此提出,应用该烈度衰减关系估计震害面积时,应根据烈度大小适当放大或缩写模型面积,具体缩放度如下:8度区模型面积放大约1.5—2.0倍,7度区模型面积缩小约1.5—1.6倍,6度区模型面积缩小约1.8—2.0 倍。     

基于公路单曲线三维坐标计算编程模型

可编程序计算器在公路放样坐标计算没有真正实现数据资源共享和有效连接。本文建立三维坐标计算模型,并对计算进行一一剖析,同时给出其通用的计算公式,为优化组合创造了条件,也为二维计算转三维计算打下了基础。一段曲线起算数据仅一次键入,计算的任意性和无限循环性,使野外放样人员作业效率大大提升,实践表明,该方法是可行的,计算模型是可靠的。     

智慧地球时代测绘地理信息学的新使命

本文首先指出智慧地球是数字地球、物联网和云计算等有机的融合,随后分析了智慧地球的主要特性,并重点阐述了智慧地球时代测绘地理信息学的新使命。作者认为我们已经从绘制地形图为主的小测绘发展成为当今以地理空间信息服务为主的大测绘,现在必须抓住机遇,不失时机地拓展智慧地球时代测绘地理信息学的新使命,将传统测绘提升为能够实时、智能地采集和处理海量空间数据、提供空间信息和知识服务的智慧测绘新阶段。     

Rural and Urban: Using American FactFinder on the Census Bureau Web Site Lesson Plan: Grades Four through Eight

Abstract

Regional survey courses are often perceived as ancillary to the systematic foci taught by geography programs. This situation stands in contrast to the recent recovery of place and region as key elements in the practice and theory of geography. In this article, I outline one possible approach for bridging the gap between regional geography's revival in theory and research and its instruction in the classroom. This approach is described in the context of a survey course about the former Soviet Union—a region where the conventional boundaries of place have been severely questioned by political, economic, and social upheavals.     

Multiple interfaces of the European Landscape Convention

The multiple interfaces of the European Landscape Convention were the topic of a roundtable panel discussion held at the meeting of the Permanent European Conference for the Study of the Rural Landscape in September 2006. The roundtable was convened by Kenneth R. Olwig, who together with four other speakers presented the main topics for discussion. Their presentations are given here as a series of short articles. Initially a brief historical background and the main provisions of the European Landscape Convention (Florence Convention) of 2000, in force 2004, are presented. The interfaces with law, landscape ecology, heritage, and globalisation are then successively discussed. Finally, the European Landscape Convention itself is examined as a discursive interface, with contradictory as well as synergetic aspects.     

基于流速衰减特征的泥石流冲出距离预测方法

泥石流冲出距离的确定是泥石流灾害评价及防治中的关键环节。基于泥石流在堆积区流速的变化特征,提出了泥石流流速"衰减系数"的概念。通过对泥石流流速衰减系数的定义和计算公式的推导,提出了一种基于泥石流流速衰减系数来确定泥石流冲出距离的新方法,并以四川省泸定县干沟泥石流为实例进行计算和验证。研究结果表明:当干沟泥石流在堆积区的流速大于初始(沟口)流速的15%时,流速的衰减程度极为显著;而当堆积区流速小于初始速度的15%时,流速的衰减极为缓慢。研究结果对泥石流灾害的危险性评价及防灾减灾具有一定的理论和实践意义。     

An economical optical cloud/fog detector

A new, relatively low cost instrument has been developed to detect the presence of fog or cloud for fog/cloud sampling applications. The instrument uses attenuation of an 880 nm light emitting diode signal to detect cloud/fog drops in the optical path between a sending and receiving arm. Laboratory and field testing under a variety of conditions and fog types were carried out to determine the ability of the optical fog detector (OFD) to accurately detect cloud/fog presence as well as to provide some measure of liquid water content. Results indicated that the OFD provided a reliable estimate of fog presence as well as a reasonable estimate of liquid water content (LWC) under several different conditions. The OFD does appear to have an interference from rain, resulting in an overestimation of LWC during rainfall. This may occasionally give a false positive indication of fog presence.     

农业气象类科技成果推广应用经济效益分析方法探讨

以科技部农业科技成果转化项目“黄淮平原农业干旱监测预警及综合防御技术推广应用”为例,对科学技术进步奖经济效益分析项目逐项解析后得出：该项目推广应用经济效益显著,对农业经济的贡献主要是节约开支、减少水资源和作物秸秆的无效浪费,对于培肥地力、改善作物的土壤生态环境以及对当季和下茬作物高产具有十分重要的意义。但对于改善生态环境而获得的生态效益分析方法,需利用其他指标进一步探讨。