A multi-band approach to unsupervised scale parameter selection for multi-scale image segmentation     

《ISPRS Journal of Photogrammetry and Remote Sensing》2014

Image segmentation is one of key steps in object based image analysis of very high resolution images. Selecting the appropriate scale parameter becomes a particularly important task in image segmentation. In this study, an unsupervised multi-band approach is proposed for scale parameter selection in the multi-scale image segmentation process, which uses spectral angle to measure the spectral homogeneity of segments. With the increasing scale parameter, spectral homogeneity of segments decreases until they match the objects in the real world. The index of spectral homogeneity is thus used to determine multiple appropriate scale parameters. The performance of the proposed method is compared to a single-band based method through qualitative visual interpretation and quantitative discrepancy measures. Both methods are applied for segmenting two images: a QuickBird scene of an urban area within Beijing, China and a Woldview-2 scene of a suburban area in Kashiwa, Japan. The proposed multi-band based segmentation scale parameter selection method outperforms the single-band based method with the better recognition for diverse land cover objects in different urban landscapes.  相似文献   

基于空间分析方法的商业选址研究——以珠海市香洲区为例     

姜亚莉  蔡心田  丁振兴 《测绘与空间地理信息》2014,(12)

选址的正确与否对商业活动的成功起着举足轻重的作用,传统的商业选址方法多以数学模型或经验法则为主,而近年来随着城镇化进程的急速发展,利用传统数理方法进行商业选址不能满足商业选址的迫切需求.本文利用GIS中的空间分析方法,以珠海中心市区香洲区为研究对象,对影响珠海市商业选址的主要因素进行空间分析,为商业选址决策提供快速有效的可视化定量分析方法.  相似文献   

遥感影像几何精校正中控制点选取的研究     

陈光洲 《现代测绘》2014,(1):14-17

在采用多项式模型进行遥感影像的几何精校正中,控制点的选取对校正精度有重要影响。本文通过实例计算,分析比较控制点的数量、分布对校正结果的影响,分析结果表明:适当增加控制点的数量会提高校正精度,但控制点数量并非越多越好;选择均匀分布的控制点有利于提高几何校正的精度。  相似文献   

A Boosted Genetic Fuzzy Classifier for land cover classification of remote sensing imagery     

D.G. StavrakoudisJ.B. Theocharis  G.C. Zalidis 《ISPRS Journal of Photogrammetry and Remote Sensing》2011,66(4):529-544

A Boosted Genetic Fuzzy Classifier (BGFC) is proposed in this paper, for land cover classification from multispectral images. The model comprises a set of fuzzy classification rules, which resemble the reasoning employed by humans. Fuzzy rules are generated in an iterative fashion, incrementally covering subspaces of the feature space, as directed by a boosting algorithm. Each rule is able to select the required features, further improving the interpretability of the obtained model. After the rule generation stage, a genetic tuning stage is employed, aiming at improving the cooperation among the fuzzy rules, thus increasing the classification performance attained after the first stage. The BGFC is tested using an IKONOS multispectral VHR image, in a lake-wetland ecosystem of international importance. For effective classification, we consider advanced feature sets, containing spectral and textural feature types. Comparative results with well-known classifiers, commonly employed in remote sensing tasks, indicate that the proposed system is able to handle multi-dimensional feature spaces more efficiently, effectively exploiting information from different feature sources.  相似文献   

矿业权实地核查的技术方法及实现     

杨文府  崔玉柱  张胤彬  郑民刚  任斗金  田丰瑞 《测绘科学》2011,36(6):61-63

为了核查全国范围内矿业权现状,摸清矿业权分布规律,全面提升全国矿业权管理水平,本文对矿业权实地核查工作的目标任务、空间基准、实地测量、资料整理、数据库建设等方面的方法及实现进行了论述;并针对生产实践中存在的技术问题,指出了解决问题的有效方法、措施,为矿业权实地核查顺利完成和数字矿山建设提供了一定依据.  相似文献   

GPS连续观测资料不同方案计算结果对比分析     

张风霜  杨国华 《测绘科学》2011,36(2):20-23

本文利用GPS连续观测资料,从单天误差、重复率统计两方面对比分析了Gamit/Globk中6种不同计算方案的结果,重点分析了参考框架的选取与约束,并总结了利于形变研究和形变信息提取的数据处理方案:对小的区域网形变分析而言,定框架时不宜使用过多的测站,应该选区域网周边较稳定的点做为框架点进行GLORG计算,通过IGS轨道...  相似文献   

植物叶片生化组分遥感反演的波段选择     

马维维  张连蓬  马向华  陈士城  郭洋洋 《测绘学院学报》2011,(3)

遥感模型PROSPECT可以反演植物叶片生化组分,不同的波段组合将会导致不同的反演结果。提出了一种带约束波段相关性最小原则的波段选择算法,并用模拟数据和实测数据对所选波段的效果进行了验证。结果表明:对于模拟数据,反演准确率超过99%;对于实测数据,叶绿素和水分的反演精度稍有提高,干物质的反演精度提高较明显。  相似文献   

一种基于复共线性分析的RPC参数优选法     

袁修孝  曹金山 《武汉大学学报(信息科学版)》2011,(6)

推导了求解有理多项式系数(RPC)的严密误差方程,从分析误差方程设计矩阵列向量间的复共线性着手,提出了一种去相关的RPC参数优选方法。对一景SPOT-5 HRG 1A级影像进行实验,结果表明,当地面控制点稀疏时,通过优选20~30个RPC参数,可以很好地消除参数间的相关性,有效消除有理函数模型(RFM)在地形拟合中出现的振荡现象,可明显提高RPC参数求解和RFM的影像几何处理精度。当地面控制点足够多时,利用此方法优选的RPC参数进行地形拟合的结果与用常规最小二乘法求解的78个RPC参数实施地形拟合的结果完全一致。  相似文献   

Ranking Regional Drought Events in China for 1960--2009     

QIAN Weihong  SHAN Xiaolong  ZHU Yafen 《大气科学进展》2011,28(2):310-321

The spatiotemporal variations of the site and regional droughts in China during 1960–2009 were analyzed by applying a daily composite-drought index (CDI) to 722 stations in mainland China. Droughts frequently happened in a zone extended from Southwest China to the Yellow River, North China, and the southwestern part of Northeast China, with two centers of high frequency in North China and Southwest China. In Southwest and South China, droughts tend to happen during the winter. In North China and along the Yellow River, droughts mainly occur during the winter and during May–June. During the past 50 years, the geographical distribution of site drought events showed high frequencies (0.9–1.3 times per year) in the upper Yellow River basin and North China, comparing with moderate frequencies (0.6–0.9 times per year) in Southwest China and the southwestern part of Northeast China and with lower frequencies over the middle and lower Yangtze River basin. And the frequencies increased over mainland China except for the upper reaches of the Yangtze River. A regional drought (RD) event is a widespread and persistent event that covers at least five adjacent sites and lasts for at least 10 days. There were 252 RD events in the past 50 years—five times per year. Most RD events lasted for <100 days and covered <100 stations, but the longest and largest RD event lasted for 307 days from 6 September 1998 to 9 July 1999 and covered 327 stations from North to Southwest China.  相似文献   

一条断裂的活动性鉴定及其工程意义     

王华林  王纪强  杜历英  盖殿广  葛孚刚  张昊  王一鹰 《地震研究》2011,34(3):331-336

拟建的某水利工程场地存在一规模较大的北北东向断裂,定名为F1断裂.通过对F1断裂的地质雷达探测、工程地质资料分析、地震地质调查、断裂断错和上覆第四纪地层年代测试等工作,鉴定了此断裂的活动性,评价了断裂对工程的影响,提出了工程选址和设计建议,为断裂活动性鉴定在工程选址和设计中的实际应用提供了一个范例.  相似文献