Modelling for registration of remotely sensed imagery when reference control points contain error

来源 :Science in China(Series D:Earth Sciences) | 被引量 : 0次 | 上传用户:xiao137wu
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Reference control points (RCPs) used in establishing the regression model in the regis-tration or geometric correction of remote sensing images are generally assumed to be “perfect”. That is, the RCPs, as explanatory variables in the regression equation, are accurate and the coordinates of their locations have no errors. Thus ordinary least squares (OLS) estimator has been applied exten-sively to the registration or geometric correction of remotely sensed data. However, this assumption is often invalid in practice because RCPs always contain errors. Moreover, the errors are actually one of the main sources which lower the accuracy of geometric correction of an uncorrected image. Under this situation, the OLS estimator is biased. It cannot handle explanatory variables with errors and cannot propagate appropriately errors from the RCPs to the corrected image. Therefore, it is essential to develop new feasible methods to overcome such a problem. This paper introduces a consistent adjusted least squares (CALS) estimator and proposes relaxed consistent adjusted least squares (RCALS) estimator, with the latter being more general and flexible, for geometric correction or regis-tration. These estimators have good capability in correcting errors contained in the RCPs, and in propagating appropriately errors of the RCPs to the corrected image with and without prior information. The objective of the CALS and proposed RCALS estimators is to improve the accuracy of measure-ment value by weakening the measurement errors. The conceptual arguments are substantiated by a real remotely sensed data. Compared to the OLS estimator, the CALS and RCALS estimators give a superior overall performance in estimating the regression coefficients and variance of measurement errors. Reference control points (RCPs) used in establishing the regression model in the regis-tration or geometric correction of remote sensing images are generally assumed to be “perfect.” That is, the RCPs, as explanatory variables in the regression equation, are accurate and However, this coordinates of their locations have no errors. As ordinary least squares (OLS) estimator has been applied exten-sively to the registration or geometric correction of remotely sensed data. However, this assumption is often invalid in practice because RCPs always contain inaccuracies. , the errors are actually one of the main sources which lower the accuracy of geometric correction of an uncorrected image. Under this situation, the OLS estimator is biased. image. Therefore, it is essential to develop new feasible methods to overcome such a problem. This paper introduces a consistent adju These estimators have good capabilities in correcting errors contained in the RCPs, and in propagating appropriately errors of the RCPs to the corrected image with and without prior information. The objective of the CALS and proposed RCALS estimators is to improve the accuracy of measure-ment value by weakening the measurement errors. The conceptual arguments are substantiated by a real Compared to the OLS estimator, the CALS and RCALS estimators give a superior overall performance in estimating the regression coefficients and variance of measurement errors.
其他文献
目的:探讨期中考试应激对卫校学生心理状况及考试成绩的影响.方法:采用症状自评量表(SCL-90)、焦虑自评量表(SAS)及抑郁自评量表(SDS),在卫校学生期中考试前夕,对212名参加期
目的:观察糖尿病患者肾功系统(血、尿β2微球蛋白、尿白蛋白、尿球蛋白),并探讨其临床意义.方法:对170例用常规方法检查尿蛋白呈阳性或弱阳性的2型糖尿病患者,同时检测肾功系
目的:观察大剂量维生素C(Vit.C)对肝硬化患者的降酶退黄作用与其作用机制.方法:Vit.C10克稀释于5%葡萄糖300-500ml中静脉点滴,每日1次,连用14-16天.观察加用及未用Vit.C治疗
目的:为提高对突发昏迷病因的临床诊断正确率,减少误诊、误治,改善病人预后提供依据.方法:对我科1997年3月至1999年6月资料较完整的148例突发昏迷病例进行分析及文献复习.结
目的 探讨心肌缺血预适应对梗死心肌的保护作用.方法 对50例急性心肌梗死(AMI)患者按发病前48h内有无心绞痛分为有缺血预适应组(IP24例)及非缺血预适应组(NIP 26例),并对各组
目的:探讨陈旧心梗与健康老人的心率,心律失常及心肌缺血发生的差异.方法:回顾性地随诊分析134例陈旧心梗患者和144例健康老人的24小时动态心电图.结果:①陈旧心梗者与健康老
从质体前体合成具有活性的叶绿体是植物生长过程中受到核基因和细胞质基因双重调控的代谢过程之一。但是,细胞质基因的调控能力是有限的,叶绿体的形成绝大部分受到核基因的调
目的:探讨国产静脉丙种球蛋白(IVIG)对小儿急性病毒性心肌炎的临床疗效.方法:设ⅣIG治疗组(n=29)及常规治疗组(n=30),比较两组症状消失时间、心电图、心肌酶谱;同时测定外周
目的:比较西地兰加倍它乐克或硝酸甘油对快速房颤诱发的心绞痛的疗效.方法:将41例既往确诊为冠心病,此次因突发快速房颤引起心绞痛的患者随机分为西地兰加倍它乐克治疗组(B)
寻找新的角度通讯写作,切忌“照葫芦画瓢”、“炒陈饭”。怎样选择新的角度,写出具有新意的通讯,这确实是写作中不可忽视的问题。怎样才能选择好新颖的角度呢?采写实践证明,