This paper presents a framework for road network change detection in order to update the Canadian National Topographic DataBase (NTDB). The methodology has been developed on the basis of road extraction from IRS\|pan ...This paper presents a framework for road network change detection in order to update the Canadian National Topographic DataBase (NTDB). The methodology has been developed on the basis of road extraction from IRS\|pan images (with a 5.8 m spatial resolution) by using a wavelet approach. The feature matching and conflation techniques are used to road change detection and updating. Elementary experiments have showed that the proposed framework could be used for developing an operational road database updating system.展开更多
The conflation of geographic datasets is one of the key technologies in the realm of spatial data capture and integration in geographic information system (GIS). Map conflation is a complex process of matching and mer...The conflation of geographic datasets is one of the key technologies in the realm of spatial data capture and integration in geographic information system (GIS). Map conflation is a complex process of matching and merging spatial data. Due to various reasons such as errors in original data related to map data discrepancies,a great amount of uncertainties exists during the process and this will result in errors in featuring matching,especially point feature. Thus,it is vital to develop the method to detect the errors in feature matching and further the conflation results will not be affected. In this paper,error matching detection and robust estimation adjustment methods are proposed for map conflation. The characteristics of errors in feature matching are first analyzed,then a new approach for map conflation based on the least-squares adjustment is presented,and a robust estimation adjustment method is further proposed to detect and process matching errors. The results of the map conflation test show that the proposed method not only determines the errors in feature matching,but also obtains the optimal merging results in map conflation.展开更多
Recently,I attended a conference organised by the European Food Safety Authority in the beautiful and prosperous Italian city of Parma.The overall topic of the conference was risk assessment,and the program included a...Recently,I attended a conference organised by the European Food Safety Authority in the beautiful and prosperous Italian city of Parma.The overall topic of the conference was risk assessment,and the program included a section on aspects of environmental risk assessment.In various areas,including the evalution of the effects of pesticide applications,invasive organisms or genetically modified plants(Arpaia et al.,2014)preparing an environmental risk assessment is an obviously relevant exercise.展开更多
文摘This paper presents a framework for road network change detection in order to update the Canadian National Topographic DataBase (NTDB). The methodology has been developed on the basis of road extraction from IRS\|pan images (with a 5.8 m spatial resolution) by using a wavelet approach. The feature matching and conflation techniques are used to road change detection and updating. Elementary experiments have showed that the proposed framework could be used for developing an operational road database updating system.
基金the National Natural Science Foundation of China (Grant Nos. 40771174 and 40301043)the Doctoral Program of Higher Education of China (Grant No. 20070247046)+1 种基金the Program for ShuGuang Scholarship of Shanghai (Grant No. 07SG24)Foundation of Shanghai Ris-ing-Star Program (Grant No. 05QMX1456)
文摘The conflation of geographic datasets is one of the key technologies in the realm of spatial data capture and integration in geographic information system (GIS). Map conflation is a complex process of matching and merging spatial data. Due to various reasons such as errors in original data related to map data discrepancies,a great amount of uncertainties exists during the process and this will result in errors in featuring matching,especially point feature. Thus,it is vital to develop the method to detect the errors in feature matching and further the conflation results will not be affected. In this paper,error matching detection and robust estimation adjustment methods are proposed for map conflation. The characteristics of errors in feature matching are first analyzed,then a new approach for map conflation based on the least-squares adjustment is presented,and a robust estimation adjustment method is further proposed to detect and process matching errors. The results of the map conflation test show that the proposed method not only determines the errors in feature matching,but also obtains the optimal merging results in map conflation.
文摘Recently,I attended a conference organised by the European Food Safety Authority in the beautiful and prosperous Italian city of Parma.The overall topic of the conference was risk assessment,and the program included a section on aspects of environmental risk assessment.In various areas,including the evalution of the effects of pesticide applications,invasive organisms or genetically modified plants(Arpaia et al.,2014)preparing an environmental risk assessment is an obviously relevant exercise.
