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International Journal of Digital Earth 2022年第1期15卷 1169-1186页

作者： Yiming Zhang Sergii Skakun Michael Oluwatosin Adegbenro Qing Ying Department of Geographical Sciences University of MarylandCollege ParkMDUSA NASA Goddard Space Flight Center Code 619 GreenbeltMDUSA Earth System Science Interdisciplinary Center University of MarylandCollege ParkMDUSA

Worldwide economic development and population growth have led to unprecedented changes in urban land use in the twenty-first century. As satellite data become available at higher spatial (3–10 m) and temporal (1–3 days) resolution,new opportunities arise to map and quantify urban area changes. While deep learning (DL) models have recently shown great performance when dealing with satellite data,their training requires a lot of labeled data which are not necessarily available at global scale. Satellite benchmark datasets,commonly used to advance methods,provide labeled data,but are rarely used for mapping and area estimation outside the training data. In this study,we aim to utilize the Sentinel-2-based benchmark dataset,Onera Satellite Change Detection (OSCD),to train a DL model and analyze its performance at local scale to map urban land use changes,estimate area of changes and provide characterization of changes. We apply the model over the Washington DC–Baltimore area for 2018–2019. We show that in just one year almost 1% of the total urban area underwent changes with the majority coming from the construction of commercial buildings,followed by residential buildings. Almost 10% of changes were attributed to the construction of new or renovation of existing schools.

关键词： Sentinel-2 urban area change detection deep learning

On the topographic entity-oriented digital elevation model construction method for urban area land surface

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维普期刊数据库

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Frontiers of Earth Science 2021年第3期15卷 580-594页

作者： Mingwei ZHAO Ling JIANG Chun WANG Cancan YANG Xin YANG College of Geographic and Tourism Chuzhou UniversityChuzhou 239000China State Key Laboratory of Resources and Environmental Information System Beijing 100101China College of Foreign Languages Chuzhou UniversityChuzhou 239000China

Human activity transforms a land surface into a complex surface where artificial and natural landforms coexist and continuous and emergent landforms merge.In this background,the problems of conventional digital elevation models(DEMs),such as morphological distortion,complicated updates,and lack of information,are increasingly prominent.This study proposes a new idea of DEM construction based on the concept of geographic ontology.First,landforms with common features are abstracted into a certain type of topographic entity based on their morphologies and semantics.For each type of topographic entity,a DEM was constructed independently based on the available elevation information and other information about the semantics and spatial relationships.Second,individual DEMs were merged into a complete DEM following certain rules.A 1 km2 area located in the suburb of Nanjing,Jiangsu Province,China,was selected as the experimental area.The effectiveness of the model construction method proposed in this study was verified.The results show that the DEM constructed according to the idea of this study has a significantly better performance than the conventional DEMs.The constructed DEM in this study can well represent ground objects,such as slopes,farmland,and ditches.In particular,the constructed DEM ensures the morphological accuracy of the ground objects.

关键词： topographic entity DEM urban area artificial strip terrain morphological accuracy

Automatic registration of MLS point clouds and SfM meshes of urban area

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Geo-Spatial Information Science 2016年第3期19卷 171-181页

作者： Reiji Yoshimura Hiroaki Date Satoshi Kanai Ryohei Honma Kazuo Oda Tatsuya Ikeda Graduate School of Information Science and Technology Hokkaido UniversitySapporoJapan Asia Air Survey Co. LtdKawasakiJapan

Recent advances in 3D scanning technologies allow us to acquire accurate and dense 3D scan data of large-scale environments efficiently.Currently,there are various methods for acquiring largescale 3D scan data,such as Mobile Laser Scanning(MLS),Airborne Laser Scanning,Terrestrial Laser Scanning,photogrammetry and Structure from Motion(SfM).Especially,MLS is useful to acquire dense point clouds of road and road-side objects,and SfM is a powerful technique to reconstruct meshes with textures from a set of digital images.In this research,a registration method of point clouds from vehicle-based MLS(MLS point cloud),and textured meshes from the SfM of aerial photographs(SfM mesh),is proposed for creating high-quality surface models of urban areas by combining them.In general,SfM mesh has non-scale information;therefore,scale,position,and orientation of the SfM mesh are adjusted in the registration process.In our method,first,2D feature points are extracted from both SfM mesh and MLS point cloud.This process consists of ground-and building-plane extraction by region growing,random sample consensus and least square method,vertical edge extraction by detecting intersections between the planes,and feature point extraction by intersection tests between the ground plane and the edges.Then,the corresponding feature points between the MLS point cloud and the SfM mesh are searched efficiently,using similarity invariant features and hashing.Next,the coordinate transformation is applied to the SfM mesh so that the ground planes and corresponding feature points are adjusted.Finally,scaling Iterative Closest Point algorithm is applied for accurate registration.Experimental results for three data-sets show that our method is effective for the registration of SfM mesh and MLS point cloud of urban areas including buildings.

关键词： Registration MLS point clouds SfM mesh urban area hash similarity invariant feature

Estimating HIV Incidence Rates among MSM in an urban area of Chongqing Using Three Approaches

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Biomedical and Environmental Sciences 2017年第12期30卷 913-916页

作者： HAN Mei PAN Ping Liang WU Guo Hui ZHOU Chao YAO Yuan LUO Juan ZOU Jing Bo ZHANG Bo Department of Laboratory Medicine Southwest Hospital Third Military Medical University Department of AIDS/STDs Control and Prevention Chongqing Municipal Centers for Disease Control and Prevention National Reference HIV/AIDS Laboratory National Center for AIDS/STDs Control and Prevention

To evaluate the HIV pandemic in Chongqing, the pooled PCR, IgG-capture BED enzyme immunoassay （BED-CEIA）, and cohort observations were used to estimate the HIV incidences among men who have sex with men （MSM）. 617 MSM subjects completed the survey at a voluntary counseling and testing （VCT） site. The observed HIV incidence was 12.5 per 100 P-Ys （95% CI = 9.1-15.7）.

关键词： Estimating HIV urban area

Numerical Study on the Impacts of Heterogeneous Reactions on Ozone Formation in the Beijing urban area

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Advances in Atmospheric Sciences 2006年第4期23卷 605-614页

作者：徐峻张远航王玮 College of Environmental Sciences Peking University Chinese Research Academy of Environmental Sciences

The air quality model CMAQ-MADRID （Community Multiscale Air Quality-Model of Aerosol Dynamics, Reaction, Ionization and Dissolution） was employed to simulate summer O3 formation in Beijing China, in order to explore the impacts of four heterogeneous reactions on O3 formation in an urban area. The results showed that the impacts were obvious and exhibited the characteristics of a typical response of a VOC-limited regime in the urban area. For the four heterogeneous reactions considered, the NO2 and HO2 heterogeneous reactions have the most severe impacts on O3 formation. During the O3 formation period, the NO2 heterogeneous reaction increased new radical creation by 30%, raising the atmospheric activity as more NO→NO2 conversion occurred, thus causing the O3 to rise. The increase of O3 peak concentration reached a maximum value of 67 ppb in the urban area. In the morning hours, high NO titration reduced the effect of the photolysis of HONO, which was produced heterogeneously at night in the surface layer. The NO2 heterogeneous reaction in the daytime is likely one of the major reasons causing the O3 increase in the Beijing urban area. The HO2 heterogeneous reaction accelerated radical termination, resulting in a decrease of the radical concentration by 44% at the most. O3 peak concentration decreased by a maximum amount of 24 ppb in the urban area. The simulation results were improved when the heterogeneous reactions were included, with the O3 and HONO model results close to the observations.

关键词： heterogeneous reactions ozone air quality model impacts urban area

Localization and mapping in urban area based on 3D point cloud of autonomous vehicles

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Journal of Beijing Institute of Technology 2016年第4期25卷 473-482页

作者：王美玲李玉杨毅朱昊刘彤 Key Laboratory of Intelligent Control and Decision of Complex System School of AutomationBeijing Institute of Technology

In order to meet the application requirements of autonomous vehicles, this paper proposes a simultaneous localization and mapping （SLAM） algorithm, which uses a VoxelGrid filter to down sample the point cloud data, with the combination of iterative closest points （ICP） algorithm and Gaussian model for particles updating, the matching between the local map and the global map to quantify particles＇ importance weight. The crude estimation by using ICP algorithm can find the high probability area of autonomous vehicles＇ poses, which would decrease particle numbers, increase algorithm speed and restrain particles＇ impoverishment. The calculation of particles＇ importance weight based on matching of attribute between grid maps is simple and practicable. Experiments carried out with the autonomous vehicle platform validate the effectiveness of our approaches.

关键词： simultaneous localization and mapping （SLAM） Rao-Blackwellized particle filter （ RB-PF） VoxelGrid filter ICP algorithm Gaussian model urban area

Large Scale Finite Element Modeling,Simulation and Visualization for Wind Flows in urban area Using Virtual Reality

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Tsinghua Science and Technology 2008年第S1期13卷 84-89页

作者： Kazuo Kashiyama Tomosato Takada Hideo Miyachi Department of Civil Engineering Chuo University Visualization Development Division KGT Inc.

A large-scale finite element modeling, simulation and visualization for wind flows are presented. The modeling method using GIS/CAD data is employed. The stabilized parallel finite element method based on SUPG/PSPG method is employed for the analysis of wind flows. The present method is applied to the simulation of wind flow and contaminant spread in urban area. The visualization based on virtual reality is employed to evaluate the mesh quality and computational results. The computed results are qualitatively in agreement with the experimental results and actual phenomena. The present method is shown to be a useful tool to simulate the wind flows in urban area.

关键词： virtual reality CAD/GIS urban area wind flows

Impacts of pollution heterogeneity on population exposure in dense urban areas using ultra-fine resolution air quality data

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Journal of Environmental Sciences 2023年第3期125卷 513-523页

作者： Wenwei Che Yumiao Zhang Changqing Lin Yik Him Fung Jimmy C.H.Fung Alexis KHLau Division of Environment and Sustainability The Hong Kong University of Science and TechnologyClear Water BayHong KongChina Department of Mathematics The Hong Kong University of Science and TechnologyClear Water BayHong KongChina Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyClear Water BayHong KongChina Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Hong Kong University of Science and TechnologyClear Water BayHong KongChina

Traditional air quality data have a spatial resolution of 1 km or above, making it challenging to resolve detailed air pollution exposure in complex urban areas. Combining urban morphology, dynamic traffic emission, regional and local meteorology, physicochemical transformations in air quality models using big data fusion technology, an ultra-fine resolution modeling system was developed to provide air quality data down to street level. Based on one-year ultra-fine resolution data, this study investigated the effects of pollution heterogeneity on the individual and population exposure to particulate matter(PM_(2.5)and PM_(10)),nitrogen dioxide(NO_(2)), and ozone(O_(3)) in Hong Kong, one of the most densely populated and urbanized cities. Sharp fine-scale variabilities in air pollution were revealed within individual city blocks. Using traditional 1 km average to represent individual exposure resulted in a positively skewed deviation of up to 200% for high-end exposure individuals. Citizens were disproportionally affected by air pollution, with annual pollutant concentrations varied by factors of 2 to 5 among 452 District Council Constituency areas(DCCAs) in Hong Kong, indicating great environmental inequities among the population. Unfavorable city planning resulted in a positive spatial coincidence between pollution and population, which increased public exposure to air pollutants by as large as 46% among districts in Hong Kong. Our results highlight the importance of ultra-fine pollutant data in quantifying the heterogeneity in pollution exposure in the dense urban area and the critical role of smart urban planning in reducing exposure inequities.

关键词： Particulate matter Nitrogen dioxide Ozone Pollution heterogeneity urban area

Acoustical environment of urban area related to the city development

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Journal of Environmental Sciences 1998年第3期10卷 79-84页

作者：  Liu XiaotuDepartment of Architecture, Southeast University, Nanjing 210096, China 

The relationship between urban development and noise pollution was analyzed. The analysis, based on a wide range of measurements and statistical data,revealed the changes of the ambient noise resulting from city development. In conclusion, some fundamental measures for improving the acoustical environment were suggested, such as the division of cities into functional areas and the development of a well designed road network. In addition, the town planning, architecture and the implementation of appropriate regulations could also help to reduce noise levels was suggested as well.

关键词： acoustical environment city planning urban area road network sound barrier.

Exploring patterns and consequences of land consumption in a coastal city-region

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Ecological Processes 2022年第1期11卷 669-693页

作者： Hashem Dadashpoor Zahra Hasankhani urban and Regional Planning DepartmentFaculty of Arts and ArchitectureTarbiat Modares UniversityTehranIran Researcher of urban and Regional Planning Faculty of Arts and ArchitectureTarbiat Modares UniversityTehranIran

Background:The rapid expansion of built-up areas and land consumption with unsustainable spatial patterns in coastal urban areas has become a global major concern due to its far-reaching consequences for human daily life,environmental sustainability,and living organisms.However,the research on this phenomenon in these areas has received less attention.To fill this gap,we conducted a study to explore the spatial patterns of land consumption at both micro-and macro-levels and to evaluate its consequences in terms of sustainable development in a coastal city-region of Mazandaran Province in northern Iran.To achieve these two goals,we combined two methods of urban land density function and landscape expansion index(LEI)to explore spatial patterns of land consumption and also evaluated the sustainability of the region with two methods of the hierarchical analytical process(AHP)and urban sustainability index(USI).Results:The spatial patterns of land consumption in the city-region of Mazandaran from 1996 to 2016 at the macro-level changed from a decentralized-sprawl to a centralized-sprawl pattern.At the micro-level,the dominant spatial pattern of land consumption in the city-region changed gradually from the outlying pattern towards the edge expansion and infilling patterns.Also,the spatial pattern of the built-up patches in the majority of the urban areas had conformity with the dominant pattern of the region.Besides,the spatial patterns of land consumption in the region were in an unsustainable state and were changing towards more unsustainability.The absence of urban containment policies and plans could lead to further destruction of the natural environment and increase its unsustainability.Conclusions:Our results indicate that the urban areas of the coastal Mazandaran have the same behavior in the spatial pattern of land consumption at the macro-and micro-levels and all are in the same direction and follow the dominant pattern of the region.

关键词： Land consumption Land use change Spatial pattern urban growth Sprawl Sustainability Consequence urban area