Over the years,transit-oriented development (TOD) has provided many countries with valuable theoretical methods and experience to deal with urban traffic congestion,environmental pollution,energy consumption and other...Over the years,transit-oriented development (TOD) has provided many countries with valuable theoretical methods and experience to deal with urban traffic congestion,environmental pollution,energy consumption and other problems.After decades of rapid urbanization,many cities in China are facing more complex challenges in transportation than ever before.This paper introduces and critically analyzes the practical application of TOD under different backgrounds and modes.Taking Shijiazhuang City,Hebei Province,China as the main case,this paper discusses and evaluates the intervention role of TOD in China’s urban transportation planning,and critically reflects on the deficiency of TOD’s transformation from theory to practice.展开更多
High-Speed Rail(HSR)has increasingly become an important mode of inter-city transportation between large cities.Inter-city interaction facilitated by HSR tends to play a more prominent role in promoting urban and regi...High-Speed Rail(HSR)has increasingly become an important mode of inter-city transportation between large cities.Inter-city interaction facilitated by HSR tends to play a more prominent role in promoting urban and regional economic integration and development.Quantifying the impact of HSR’s interaction on cities and people is therefore crucial for long-term urban and regional development planning and policy making.We develop an evaluation framework using toponym information from social media as a proxy to estimate the dynamics of such impact.This paper adopts two types of spatial information:toponyms from social media posts,and the geographical location information embedded in social media posts.The framework highlights the asymmetric nature of social interaction among cities,and proposes a series of metrics to quantify such impact from multiple perspectives-including interaction strength,spatial decay,and channel effect.The results show that HSRs not only greatly expand the uneven distribution of inter-city connections,but also significantly reshape the interactions that occur along HSR routes through the channel effect.展开更多
The advent of information and communication technology and the Internet of Things have led our society toward a digital era.The proliferation of personal computers,smartphones,intelligent autonomous sensors,and pervas...The advent of information and communication technology and the Internet of Things have led our society toward a digital era.The proliferation of personal computers,smartphones,intelligent autonomous sensors,and pervasive network interactions with individuals have gradually shifted human activities from offline to online and from in person to virtual.This transformation has brought a series of challenges in a variety of fields,such as the dilemma of placelessness,some aspects of timelessness(no time relevance),and the changing relevance of distance in the field of geographic information science(GIScience).In the last two decades,“cyber thinking”in GIScience has received significant attention from different perspectives.For instance,human activities in“cyberspace”need to be reconsidered when coupled with the geographic space to observe the first law of geography.展开更多
Simultaneous Localization and Mapping(SLAM)has been widely used in emergency response,self-driving and city-scale 3D mapping and navigation.Recent deep-learning based feature point extractors have demonstrated superio...Simultaneous Localization and Mapping(SLAM)has been widely used in emergency response,self-driving and city-scale 3D mapping and navigation.Recent deep-learning based feature point extractors have demonstrated superior performance in dealing with the complex environmental challenges(e.g.extreme lighting)while the traditional extractors are struggling.In this paper,we have successfully improved the robustness and accuracy of a monocular visual SLAM system under various complex scenes by adding a deep learning based visual localization thread as an augmentation to the visual SLAM framework.In this thread,our feature extractor with an efficient lightweight deep neural network is used for absolute pose and scale estimation in real time using the highly accurate georeferenced prior map database at 20cm geometric accuracy created by our in-house and low-cost LiDAR and camera integrated device.The closed-loop error provided by our SLAM system with and without this enhancement is 1.03m and 18.28m respectively.The scale estimation of the monocular visual SLAM is also significantly improved(0.01 versus 0.98).In addition,a novel camera-LiDAR calibration workflow is also provided for large-scale 3D mapping.This paper demonstrates the application and research potential of deep-learning based vision SLAM with image and LiDAR sensors.展开更多
The Sendai Framework for Disaster Risk Reduction 2015−2030’s(SFDRR)framing moved away from disaster risk as a natural phenomenon to the examination of the inequality and injustice at the root of human vulnerability t...The Sendai Framework for Disaster Risk Reduction 2015−2030’s(SFDRR)framing moved away from disaster risk as a natural phenomenon to the examination of the inequality and injustice at the root of human vulnerability to hazards and disasters.Yet,its achievements have not seriously challenged the long-established capitalist systems of oppression that hinder the development leading to disaster risk creation.This article is an exploratory mapping exercise of and a collective reflection on Sustainable Development Goals(SDGs)and SFDRR indicators-and their use in measuring progress towards disaster risk reduction(DRR).We highlight that despite the rhetoric of vulnerability,the measurement of progress towards DRR remains event/hazard-centric.We argue that the measurement of disaster risk could be greatly enhanced by the integration of development data in future iterations of global DRR frameworks for action.展开更多
文摘Over the years,transit-oriented development (TOD) has provided many countries with valuable theoretical methods and experience to deal with urban traffic congestion,environmental pollution,energy consumption and other problems.After decades of rapid urbanization,many cities in China are facing more complex challenges in transportation than ever before.This paper introduces and critically analyzes the practical application of TOD under different backgrounds and modes.Taking Shijiazhuang City,Hebei Province,China as the main case,this paper discusses and evaluates the intervention role of TOD in China’s urban transportation planning,and critically reflects on the deficiency of TOD’s transformation from theory to practice.
基金This work is supported by the National Natural Science Foundation of China[grant numbers 41801378,42071382].
文摘High-Speed Rail(HSR)has increasingly become an important mode of inter-city transportation between large cities.Inter-city interaction facilitated by HSR tends to play a more prominent role in promoting urban and regional economic integration and development.Quantifying the impact of HSR’s interaction on cities and people is therefore crucial for long-term urban and regional development planning and policy making.We develop an evaluation framework using toponym information from social media as a proxy to estimate the dynamics of such impact.This paper adopts two types of spatial information:toponyms from social media posts,and the geographical location information embedded in social media posts.The framework highlights the asymmetric nature of social interaction among cities,and proposes a series of metrics to quantify such impact from multiple perspectives-including interaction strength,spatial decay,and channel effect.The results show that HSRs not only greatly expand the uneven distribution of inter-city connections,but also significantly reshape the interactions that occur along HSR routes through the channel effect.
基金This work was supported by the National Basic Research Program of China (No. 2012CB955800), the National Social Science Foundation of China (Grant No. 14CGJ025) and the CAS Strategic Priority Research Program (Grant No. XDA05150900).
文摘The advent of information and communication technology and the Internet of Things have led our society toward a digital era.The proliferation of personal computers,smartphones,intelligent autonomous sensors,and pervasive network interactions with individuals have gradually shifted human activities from offline to online and from in person to virtual.This transformation has brought a series of challenges in a variety of fields,such as the dilemma of placelessness,some aspects of timelessness(no time relevance),and the changing relevance of distance in the field of geographic information science(GIScience).In the last two decades,“cyber thinking”in GIScience has received significant attention from different perspectives.For instance,human activities in“cyberspace”need to be reconsidered when coupled with the geographic space to observe the first law of geography.
基金supported by the National Key Research and Development Program of China under[Grant number 2019YFC1511304]supported by the Pilot Fund of Frontier Science and Disruptive Technology of Aerospace Information Research Institute,Chinese Academy of Sciences under[Grant number E0Z21101].
文摘Simultaneous Localization and Mapping(SLAM)has been widely used in emergency response,self-driving and city-scale 3D mapping and navigation.Recent deep-learning based feature point extractors have demonstrated superior performance in dealing with the complex environmental challenges(e.g.extreme lighting)while the traditional extractors are struggling.In this paper,we have successfully improved the robustness and accuracy of a monocular visual SLAM system under various complex scenes by adding a deep learning based visual localization thread as an augmentation to the visual SLAM framework.In this thread,our feature extractor with an efficient lightweight deep neural network is used for absolute pose and scale estimation in real time using the highly accurate georeferenced prior map database at 20cm geometric accuracy created by our in-house and low-cost LiDAR and camera integrated device.The closed-loop error provided by our SLAM system with and without this enhancement is 1.03m and 18.28m respectively.The scale estimation of the monocular visual SLAM is also significantly improved(0.01 versus 0.98).In addition,a novel camera-LiDAR calibration workflow is also provided for large-scale 3D mapping.This paper demonstrates the application and research potential of deep-learning based vision SLAM with image and LiDAR sensors.
基金CONVERGE COVID-19 funding for supporting the foundation of the Disaster Capitalism and COVID-19 Working Group.
文摘The Sendai Framework for Disaster Risk Reduction 2015−2030’s(SFDRR)framing moved away from disaster risk as a natural phenomenon to the examination of the inequality and injustice at the root of human vulnerability to hazards and disasters.Yet,its achievements have not seriously challenged the long-established capitalist systems of oppression that hinder the development leading to disaster risk creation.This article is an exploratory mapping exercise of and a collective reflection on Sustainable Development Goals(SDGs)and SFDRR indicators-and their use in measuring progress towards disaster risk reduction(DRR).We highlight that despite the rhetoric of vulnerability,the measurement of progress towards DRR remains event/hazard-centric.We argue that the measurement of disaster risk could be greatly enhanced by the integration of development data in future iterations of global DRR frameworks for action.
基金support from the National Research FoundationPrime Minister’s Office+7 种基金Singapore under its Campus for Research Excellence and Technological Enterprise(CREATE)programmeThe Hong Kong Polytechnic University Strategic Hiring Scheme(P0036221)support from the Key Program of National Natural Science Foundation of China(41930648)supports from the Hong Kong Research Grants Council(15602619,15603920,and C7064-18GF)supports from the Hong Kong Research Grants Council(14605920,14611621,and C4023-20GF)support from the National University of SingaporeMinistry of Education,Tier 1 under WBS R-109-000-270-133Ministry of Natural Resources of the People’s Republic of China(GS(2021)7327)。