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Chinese Optics Letters 2010年第6期8卷 533-536页

作者：龚威张金业毛飞跃李俊 state key laboratory for Information Engineering in surveying Mapping and Remote SensingWuhan University School of Science Hubei University of Technology

The profiles of aerosol extinction,backscatter coefficient,and lidar ratio in the lower troposphere over Wuhan are measured by a multi-channel Raman/Mie *** the lidar ratio retrieved by Raman scattering principle,the profiles of aerosol extinction and backscatter coefficients are also retrieved by Mie scattering signals,without a prior assumption about their relation in the traditional pure Mie signals data *** observations by both Raman and Mie are in good agreement with each *** high coherence shows that the system is reliable,and the Mie and Raman channels are in good adjustment and have the same field of view.

关键词： Atmospheric aerosols Backscattering Light extinction Optical radar

Object oriented land cover classification using ALS and GeoEye imagery over mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 733-737页

作者： YU Hai-yang, CHENG Gang, GE Xiao-san, LU Xiao-ping key laboratory of Mine Spatial Information Technologies of state Bureau of surveying and Mapping, Henan Polytechnic University, Jiaozuo 454000, China key laboratory of Mine Spatial Information Technologies of state Bureau of surveying and Mapping Henan Polytechnic University Jiaozuo 454000 China

An object oriented coal mining land cover classification method based on semantically meaningful image segmentation and image combination of GeoEye imagery and airborne laser scanning (ALS) data was presented. First, DEM, DSM and nDSM (normalized Digital Surface Model, nDSM) were extracted from ALS data. The GeoEye imagery and DSM data were combined to create segmented objects based on neighbor regions merge method. Then 10 kinds of objects were extracted. Different kinds of vegetation objects, including crop, grass, shrub and tree, can be extracted by using NDVI and height value of nDSM. Water and coal pile field was extracted by using NDWI and the standard deviation of DSM method. Height differences also can be used to distinguish buildings from road and vacant land, and accurate building contour information can be extracted by using relationship of neighbor objects and morphological method. The test result shows that the total classification accuracy of the presented method is 90.78% and the kappa coefficient is 0.891 4.

关键词： airborne laser scanning GeoEye nDSM object oriented classification mining areas

A modified Hoek-Brown failure criterion considering the damage to reservoir bank slope rocks under water saturation-dehydration circulation

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Journal of Mountain Science 2017年第4期14卷 771-781页

作者： WANG Xin-gang WANG Jia-ding GU Tian-Feng LIAN Bao-qin state key laboratory of Continental Dynamics Department of Geology Northwest University School of Geology Engineering and surveying Chang' an University

After water is impounded in a reservoir, rock mass in the hydro-fluctuation belt of the reservoir bank slope is subject to water saturation- dehydration circulation （WSDC）. To quantify the rate of change of rock mechanical properties, samples from the Longtan dam area were measured with uniaxial compression tests after different numbers （1, 5, 10, 15, and 20） of simulated WSDC cycles. Based on the curves derived from these tests, a modified Hock- Brown failure criterion was proposed, in which a new parameter was introduced to model the cumulative damage to rocks after WSDC. A case of an engineering application was analyzed, and the results showed that the modified Hock-Brown failure criterion is useful. Under similar WSDC-influenced engineering and geological conditions, rock mass strength parameters required for analysis and evaluation of rock slope stability can be estimated according to this modified Hoek-Brown failure criterion.

关键词： Modified Hoek-Brown criterion Reservoir bank slope Hydro-fluctuation belt Water saturation-dehydration circulation Damage

Estimating optimal substitution scale of urban gasoline taxis by electric taxis in the era of green energy:a case study of Zhengzhou City

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Geo-Spatial Information Science 2023年第3期26卷 514-539页

作者： Zhixiang Fang Xiaofan Wang Ying Zhuang Xianglong Liu state key laboratory of Information Engineering in surveying Mapping and Remote SensingWuhan UniversityWuhanChina key laboratory of Advanced Public Transportation Science China Academy of Transportation SciencesBeijingChina

Electric Taxis(ETs)are the most favored alternatives to Gasoline Taxis(GTs)in cities that aim to reduce environmental *** to develop a reasonable scale on which GTs are substituted by ETs remains a challenge to governments due to the dynamics and complexity of the taxi *** address this challenge,this paper develops a discrete-event-based simulation framework to simulate participants in the system and estimate the results under different substitution scales,which are helpful to understanding the status changing law of entities under different substitution scales,such as the operating indices of ETs,the unsatisfied travel requirements of passengers,and the usage state of charging *** framework abstracts the behavioral process of ETs into three elements,namely,entity,behavior,and *** entities are constructed from the information derived from the trajectory *** behaviors are defined by rules following behavioral logic under anxiety psychology,which is caused by the limited range of *** events are triggered based on rules from *** the help of this framework,a multi-objective optimization model is developed to obtain the optimal substitution scale of GTs in the case study area of Zhengzhou ***,the approach could provide a practical tool to address this challenge,which could support further studies of the effect of ETs on urban taxis.

关键词： Electric Taxi(ET) substitution scale discrete-event simulation decision support multi-objective optimization

A new relative radiometric consistency processing method for change detection based on wavelet transform and a low-pass filter

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Science China(Technological Sciences) 2010年第S1期53卷 7-14页

作者： SUN KaiMin1,SUI HaiGang1,2,LI DeRen1 & XU Chuan1,2 1 state key laboratory of Information Engineering in surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,China 2 state key laboratory of Subtropical Building Science,South China University of Technology,Guangzhou 510640,China state key laboratory of Information Engineering in surveying Mapping and Remote Sensing Wuhan University Wuhan China state key laboratory of Subtropical Building Science South China University of Technology Guangzhou China

The research purpose of this paper is to show the limitations of the existing radiometric normalization approaches and their disadvantages in change detection of artificial objects by comparing the existing approaches,on the basis of which a preprocessing approach to radiometric consistency,based on wavelet transform and a spatial low-pass filter,has been *** approach first separates the high frequency information and low frequency information by wavelet ***,the processing of relative radiometric consistency based on a low-pass filter is conducted on the low frequency *** processing,an inverse wavelet transform is conducted to obtain the results *** experimental results show that this approach can substantially reduce the influence on change detection of linear or nonlinear radiometric differences in multi-temporal images.

关键词： wavelet transform radiometric normalization low-pass filter change detection

A new approach toward object-based change detection

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Science China(Technological Sciences) 2010年第S1期53卷 105-110页

作者： ZHANG Guo1,2,LI Yang1 & LI ZhiJiang3 1 state key laboratory of Information Engineering in surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,China 2 Satellite of surveying and Mapping Application center,state Bureau of surveying and Mapping,Beijing 100830,China 3 School of Printing and Packaging,Wuhan University,Wuhan 430079,China state key laboratory of Information Engineering in surveying Mapping and Remote Sensing Wuhan University Wuhan China Satellite of surveying and Mapping Application center State Bureau of Surveying and Mapping Beijing China School of Printing and Packaging Wuhan University Wuhan China

Object-based change detection has been the hotspot in remote sensing image processing.A new approach toward object-based change detection is *** two different temporal images are unitedly segmented using the mean shift procedure to obtain corresponding *** change detection is implemented based on the integration of corresponding objects’ intensity and texture *** are conducted on both panchromatic images and multispectral images and the results show that the integrated measure is robust with respect to illumination changes and *** color detection is conducted to determine whether the color of the unchanged objects changes or not when dealing with multispectral *** verification work is carried out to show the accuracy of the proposed approach.

关键词： mean shift united segmentation change detection object-based intensity texture integration

A multi-scale and multi-orientation image retrieval method based on rotation-invariant texture features

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Science China(Information Sciences) 2011年第4期54卷 732-744页

作者： SHAO ZhenFeng,LI DeRen & ZHU XianQiang state key laboratory for Information Engineering in surveying,Mapping and Remote Sensing,Wuhan University,129 Luoyu Road,Wuhan 430079,China state key laboratory for Information Engineering in surveying Mapping and Remote Sensing Wuhan University Wuhan China

Texture retrieval is a vital branch of content-based image ***-invariant texture retrieval plays a key role in texture *** paper addresses three major issues in rotation-invariant texture retrieval: how to select the texture measurement methods,how to alleviate the influence of rotation for texture retrieval and how to apply the proper multi-scale analysis theory for texture ***,the spectrum influence between a Radon transform and a Log-polar transform was compared after the rotation effect was *** average retrieval performance of wavelet and NSCT with different retrieval parameters was also *** on such analysis,we developed a multi-scale and multi-orientation texture transform spectrum,as well as a rotation-invariant feature vector and its measurement criteria,which can represent the human visual perception sensitive to texture *** a new rotation-invariant texture retrieval algorithm was *** algorithm was developed based on non-parametric statistical features and it applies low band and high frequency directional bands of NSCT coefficients for coarse filtering and fine retrieval,*** on the Brodatz image database show that the constructed rotation-invariant feature vector is appropriate for capturing major orientations and describing detail ***,the combination of the two-step progressive retrieval strategy and multi-scale analysis method can effectively improve retrieval efficiency while ensuring a high precision compared with traditional algorithms.

关键词： NSCT Log-polar Radon rotation-invariant texture retrieval

Image City sharing platform and its typical applications

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Science China(Information Sciences) 2011年第8期54卷 1738-1746页

作者： SHAO ZhenFeng & Li DeRen state key laboratory for Information Engineering in surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,China state key laboratory for Information Engineering in surveying Mapping and Remote Sensing Wuhan University Wuhan China

In this paper,the trend of urban spatial information sharing service from the electronic map to image is analyzed and its sharing framework based on service-oriented architecture is ***,the service implementation,feedback data service procedure and its processing service model are explored. Based on the software with independent intellectual property rights,image city of Taizhou is developed as an example to realize various image data and processing servicesLastly,the bright future prospects of image city are described.

关键词： Image City service-oriented architecture image data service function service model service

Urban Geospatial Information Acquisition Mobile Mapping System based on close-range photogrammetry and IGS site calibration

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Geo-Spatial Information Science 2021年第4期24卷 558-579页

作者： Ming Guo Yuquan Zhou Jianghong Zhao Tengfei Zhou Bingnan Yan Xianfeng Huang state key laboratory of Geo-Information Engineering Xi‘An Institute of Surveying and MappingXi’anChina School of Geomatics and Urban Spatial Informatics Beijing University of Civil Engineering and ArchitectureBeijingChina Ministry of Education Engineering Research Centre of Representative Building and Architectural Heritage DatabaseBeijingChina key laboratory of Modern Urban surveying and Mapping National Administration of Surveying Mapping and GeoinformationBeijingChina Beijing key laboratory for Architectural Heritage Fine Reconstruction&Health Monitoring Beijing University of Civil Engineering and ArchitectureBeijingChina state key laboratory of Information Engineering in surveying Mapping and Remote SensingWuhan UniversityWuhanChina

The measurement accuracy of the Mobile Mapping System (MMS) is the main problem, which restricts its development and application, so how to calibrate the MMS to improve its measure-ment accuracy has always been a research hotspot in the industry. This paper proposes a position and attitude calibration method with error correction based on the combination of the feature point and feature surface. First, the initial value of the spatial position relation-ship between each sensor of MMS is obtained by close-range photogrammetry. Second, the optimal solution for error correction is calculated by feature points in global coordinates jointly measured with International GNSS Service (IGS) stations. Then, the final transformation para-meters are solved by combining the initial values obtained originally, thereby realizing the rapid calibration of the MMS. Finally, it analyzed the RMSE of MMS point cloud after calibration, and the results demonstrate the feasibility of the calibration approach proposed by this method. Under the condition of a single measurement sensor accuracy is low, the plane and elevation absolute accuracy of the point cloud after calibration can reach 0.043 m and 0.072 m, respectively, and the relative accuracy is smaller than 0.02 m. It meets the precision require-ments of data acquisition for MMS. It is of great significance for promoting the development of MMS technology and the application of some novel techniques in the future, such as auton-omous driving, digital twin city, urban brain et al.

关键词： Mobile Mapping System(MMS) close-range photogrammetry International GNSS Service(IGS) MMS calibration accuracy evaluation

Mapping impervious surfaces with a hierarchical spectral mixture analysis incorporating endmember spatial distribution

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Geo-Spatial Information Science 2022年第4期25卷 550-567页

作者： Zhenfeng Shao Yuan Zhang Cheng Zhang Xiao Huang Tao Cheng state key laboratory of Information Engineering in surveying Mapping and Remote SensingWuhanChina Department of Geosciences University of ArkansasFayettevilleARUSA

Impervious surface mapping is essential for urban environmental *** Mixture Analysis(SMA)and its extensions are widely employed in impervious surface estimation from medium-resolution *** SMA,inappropriate endmember combinations and inadequate endmember classes have been recognized as the primary reasons for estimation ***,the spectral-only SMA,without considering urban spatial distribution,fails to consider spectral variability in an adequate *** lack of endmember class diversity and their spatial variations lead to over/*** mitigate these issues,this study integrates a hierarchical strategy and spatially varied endmember spectra to map impervious surface abundance,taking Wuhan and Wuzhou as two study ***,the piecewise convex multiple-model endmember detection algorithm is applied to automatically hierarch-ize images into three regions,and distinct endmember combinations are independently developed in each ***,spatially varied endmember spectra are synthesized through neighboring spectra using the distance-based *** analysis indicates that the proposed method achieves better performance than Hierarchical SMA and Fixed Four-endmembers SMA in terms of MAE,SE,and *** analysis suggests that the hierarch-ical strategy can expand endmember class types and considerably improve the performance for the study areas in general,specifically in less developed ***,we find that spatially varied endmember spectra facilitate the reduction of heterogeneous surface material variations and achieve the improved performance in developed areas.

关键词： Impervious surface Spectral Mixture Analysis(SMA) hierarchical strategy endmember class spatially varied endmember spectra