A comparative assessment between object and pixel-based classification approaches for land use/land cover mapping using SPOT 5 imagery     

Mahyat Shafapour Tehrany  Mustafa Neamah Jebuv 《国际地球制图》2013,28(4):351-369

Abstract

Land use/land cover (LULC) classification with high accuracy is necessary, especially in eco-environment research, urban planning, vegetation condition study and soil management. Over the last decade a number of classification algorithms have been developed for the analysis of remotely sensed data. The most notable algorithms are the object-oriented K-Nearest Neighbour (K-NN), Support Vector Machines (SVMs) and the Decision Trees (DTs) amongst many others. In this study, LULC types of Selangor area were analyzed on the basis of the classification results acquired using the pixel-based and object-based image analysis approaches. SPOT 5 satellite images with four spectral bands from 2003 and 2010 were used to carry out the image classification and ground truth data were collected from Google Earth and field trips. In pixel-based image analysis, a supervised classification was performed using the DT classifier. On the other hand, object-oriented (K-NN) image analysis was evaluated using standard nearest neighbour as classifier. Subsequently SVM object-based classification was performed. Five LULC categories were extracted and the results were compared between them. The overall classification accuracies for 2003 and 2010 showed that the object-oriented (K-NN) (90.5% and 91%) performed better results than the pixel-based DT (68.6% and 68.4%) and object-based SVM (80.6% and 78.15%). In general, the object-oriented (K-NN) performed better than both DTs and SVMs. The obtained LULC classification maps can be used to improve various applications such as change detection, urban design, environmental management and zooning.  相似文献   

基于组件技术的地表蒸散发遥感监测系统设计与应用     

钱志奇  张友静  邓世赞  房莹莹  陈晨 《地球信息科学学报》2011,13(5):679-686

针对遥感模型与水热模型集成应用的需求,以C#语言结合ENVI/IDL和ArcGIS Engine混合编程技术,设计开发了地表蒸散发遥感监测系统的基本流程,对系统数据库设计及遥感模型与水热模型集成模式进行了研究,研发了单元蒸散发参数反演与结果校验功能,实现了遥感模型与水热模型的集成应用.系统对黄河三花间流域以MODIS遥...  相似文献   

Intercomparison of NO_x, SO_2, O_3, and Aromatic Hydrocarbons Measured by a Commercial DOAS System and Traditional Point Monitoring Techniques   总被引：1，自引：0，他引：1  

谢品华  刘文清  付强  王瑞斌  刘建国  魏庆农 《大气科学进展》2004,21(2)

A field-based Intercomparison study of a commercial Differential Optical Absorption Spectroscopy (DOAS) instrument (OPSIS AB, Sweden) and different point-sample monitoring techniques (PM, based on an air monitoring station, an air monitoring vehicle, and various chemical methods) was conducted in Beijing from October 1999 to January 2000. The mixing ratios of six trace gases including NO, NO2, SO2, O3, benzene, and toluene were monitored continuously during the four months. A good agreement between the DOAS and PM data was found for NO2 and SO2. However, the concentrations of benzene, toluene, and NO obtained by DOAS were significantly lower than those measured by the point monitors. The ozone levels monitored by the DOAS were generally higher than those measured by point monitors. These results may be attributed to a strong vertical gradient of the NO-O3-NO2 system and of the aromatics at the measurement site. Since the exact data evaluation algorithm is not revealed by the manufacturer of the DOAS sys  相似文献   

A remote-sensing technique for the identification of aeolian fetch distance     

KEVIN LYNCH  DEREK W. T. JACKSON  J. ANDREW G. COOPER 《Sedimentology》2006,53(6):1381-1390

This paper describes a new method for assessing aeolian fetch distances in beach/dune systems. The remote‐sensing technique has advantages over currently used proxy measures of fetch distance, such as those based on tide gauges and beach profiles. The method uses a digital camera, global positioning system surveying, and a geographical information system software package to produce a rectified image of the beach surface. From this, direct measurements of the wet–dry beach boundary can be combined with wind direction measurements to determine fetch distance. The method offers an improvement on current approaches to sediment transport estimates: a 28‐day study on Magilligan Strand, Northern Ireland, showed that the commonly used high water mark approach overestimated fetch distance by 30% compared with the technique reported here.  相似文献   

遥感技术在四川乡城地区矿产远景调查中的应用     

宋元宝  尹显科  刘智 《四川地质学报》2007,27(3):225-227

在我国西部自然条件恶劣、交通不发达的低覆盖区,遥感技术在矿产调查中发挥基础先导性作用。在部分遥感影像时相好、地层岩性差异大、变质作用轻微的地区,遥感技术有逐渐部分替代传统的地质找矿方法的趋势。通过乡城地区矿产遥感调查工作,初步总结出高海拔地区的遥感工作方法。  相似文献   

基于主成分分析的遥感图像模拟真彩色融合法     

樊旭艳  付春龙  石继海  武丽娟 《测绘学院学报》2006,(4)

对不同空间分辨率、时间分辨率和波谱分辨率的遥感图像进行综合、高效的利用,是遥感应用的关键问题之一。基于主分量变换法,提出了基于主成分分析的模拟真彩色融合法。该方法不仅具有主成分分析融合法的光谱波段选择灵活和光谱信息损失小等优点,同时该方法还可获得逼真的自然色彩的融合图像,提高了图像的融合效果。利用QuickBird全色和多光谱数据进行了试验,并与色彩空间变换法(IHS)、比值变换融合法和乘积变换法等传统方法,在定性和定量两个方面进行了比较分析。结果表明,新方法很好的保留了多光谱影像的光谱信息,提高了空间细节的表现能力,是一种有效实用的遥感图像融合方法。  相似文献   

The effects of volcanic ash on COSPEC measurements     

R. J. Andres  J. W. Schmid 《Journal of Volcanology and Geothermal Research》2001,108(1-4)

Data from a series of laboratory experiments show the relationships between measured correlation spectrometer (COSPEC) sulfur-dioxide (SO₂) burdens, automatic gain control (AGC) deflections, and visible wavelength opacities in ash-laden plumes. The data show that the COSPEC reliably measures (within a 10% accuracy) SO₂ burdens up to AGC deflections of 2 V and visible wavelength opacities of 50%. Beyond these limits, the under measurement of the SO₂ burden is not well constrained. During typical COSPEC runs, these limits are rarely violated. The 10% error introduced by measuring ash-laden plumes is acceptable because the error is small relative to other error sources associated with the technique, especially plume velocity; and the error is correctable which allows for a wider range of plume conditions to be measured.These results imply that the densest SO₂ concentrations near the volcanic source can be measured. This is important so that SO₂ is not lost from the volcanic plume due to physical and chemical processes and that measurements are conducted under maximum signal to noise ratios.  相似文献   

卫星遥感技术在江西水土流失调查中的应用   总被引：2，自引：0，他引：2  

黄越  彭泽洲  滑舸 《江西地质》2001,15(3):197-202

江西是我国南方水土流失较严重的省份之一，水土流失造成农业生态环境恶化，成为江西社会经济可持续发展中的一个主要制约因素。用遥感技术，结合全球定位系统、地理信息系统进行水土流失调查是目前国际上比较先进的方法。本文应用“3S”技术，对江西省水土流失的现状进行了调查，总结了其遥感特征和空间分布规律，论述了水土流失对江西经济社会发展的危害，进而提出了水土流失的防治对策。  相似文献   

遥感地质解译在1:5万地质填图中的应用     

杨德明  洪景鹏 《吉林大学学报(地球科学版)》1992,(2)

在辽北1:5万地质填图中应用遥感技术提供超前地质信息,加强基础地质研究程度.根据遥感图象结合航磁资料,划分出以线性影象为主的太古宙变质上壳岩系,以环形影象为主的变质深成侵入体等影象地质单元,并解译出以细线纹为标志的韧性剪切带和片麻岩中面状构造的分布趋势.  相似文献   

面向对象的遥感影像分类在地理国情普查中的应用     

陈通利  黎海波 《测绘与空间地理信息》2017,(10):108-110

遥感技术因其较高的精确性和时效性已成为监测土地利用变化的重要手段。地理国情普查是一项非常重要的调查工程,起着为各级领导干部科学决策提供数据支持的作用。遥感影像解译是整个普查工作中的重要环节,而且工作量巨大。目前,地理国情普查的遥感影像解译环节主要采用人工解译和计算机自动解译相结合的方法,以提高效率。本文主要介绍一种面向对象分类的遥感影像自动解译方法,通过东莞市TM影像实验,总结该方法的解译特点,并介绍其在地理国情普查中的应用。  相似文献