This paper analyses the overall landscape framework of city road system in ancient and modern China, using the ideal state terrain model which was fi rst recorded by the construction system of the Zhou Dynasty, and su...This paper analyses the overall landscape framework of city road system in ancient and modern China, using the ideal state terrain model which was fi rst recorded by the construction system of the Zhou Dynasty, and summarizes the ideal model of overall landscape framework of city road system, based on Chinese psychological needs of landscape, and conducts the applied research taking Nanchong in Sichuan, China for example.展开更多
Based on the idea of system,the paper had analyzed components of garden road system in urban park and their relations from the perspective of function,pattern and facility,and established framework of garden road syst...Based on the idea of system,the paper had analyzed components of garden road system in urban park and their relations from the perspective of function,pattern and facility,and established framework of garden road system for guidance of garden road construction.After introduction of the connotation of garden road system,its attributes were summarized which were isolated elements,integrated collection,clear level and dynamic development;and its functional composition had been concluded from the aspects of practical function and social function.Practical functions contained traffic organization and guidance tour,space division and landscape composition,facility organization and habitat improvement.Social functions consisted of communication and education function.The pattern of garden road system had been introduced in terms of pattern elements,level structure and layout form.Facilities of garden road system had been classified into five categories covering rest facilities,ornamental facilities,light facilities,display facilities and service facilities.展开更多
Particulate matter(PM), one of the most important pollutants of traffic emission, threatens the health of urban ecosystems and citizens. Roadside trees play an important role in trapping PM, and the foliar PM load is ...Particulate matter(PM), one of the most important pollutants of traffic emission, threatens the health of urban ecosystems and citizens. Roadside trees play an important role in trapping PM, and the foliar PM load is a useful indicator for air PM pollution in road systems. To detect the relationships of foliar PM load with road structures, urbanization, and meteorology in road systems, we studied a widely-planted tree Sophora japonica L. in 100 roads and 10 yards of Beijing, China, and found that the foliar PM loads increased with the distances from the urban centre(DUC) linearly, while decreased with the road density. All-subsets regression analysis indicated that DUC, average monthly relative humidity, average monthly wind speed, and mean annual wind speed were the most important factors in predicting foliar PM load, rather than general situation of buildings and road cleanliness. The monthly relative humidity and monthly wind speed had a negative correlation to foliar PM, while the annual relative humidity and annual wind speed had a positive correlation to foliar PM. Suburban areas and these effective factors should be highlighted in PM control in Beijing.展开更多
The rapid development of the automobile industry and the relative lag of the road construction have constituted a prominent contradiction all over the world, particularly, in most of large cities. To cope with it, ele...The rapid development of the automobile industry and the relative lag of the road construction have constituted a prominent contradiction all over the world, particularly, in most of large cities. To cope with it, elevated roads have been built in many cities both at home and abroad. However, traffic jams frequently appear on elevated roads immediately after the completion of their construction. The awkward situation mainly results from the planning bug or the unsuitable control, apart from drastic increase in transportation demand. Elevated roads,展开更多
In order to eliminate the difficulties caused by the presence of snow and ice on the road surface and to create a safe, constant and convenient movement with their design speeds and loads, companies and organizations ...In order to eliminate the difficulties caused by the presence of snow and ice on the road surface and to create a safe, constant and convenient movement with their design speeds and loads, companies and organizations should apply a set of roads winter maintenance activities. Drifted snow on the roads is determined by a group of factors, which in most cases depend on each other and occur in different combinations. The main factors are: the climate conditions, the specific features of the area, the geometric and constructive elements of the road.展开更多
With the rapid expansion of urban road networks and the increasing ownership of vehicles in many countries and regions, the greenhouse gas and pollutant emissions from road travels have become a global concern. The in...With the rapid expansion of urban road networks and the increasing ownership of vehicles in many countries and regions, the greenhouse gas and pollutant emissions from road travels have become a global concern. The introduction of electric vehicles(EVs) with dynamic charging into road systems, which is defined as electric road systems(ERSs), has been widely recognized as a viable solution to address this problem. This paper presents a comprehensive study on the reliability of power supply systems integrated with renewables for ERS(ERSPSRs), which interface with both road traffic and power networks. First, a brief introduction to the charging modes of EVs demonstrates the coupling of the two networks. A simplified traffic model is then built, based on which the reliability indices of the system considering the influence of the dynamic charging and static charging modes of EVs are proposed. Further, a simplified trip chain based Monte Carlo reliability assessment method of ERS-PSRs is proposed. Case studies based on the IEEE Roy Billinton Test System(RBTS) show that the dynamic charging mode of EVs can not only effectively balance the supply and demand of the power grid at different time(shaving peaks and filling valleys), but also significantly improve the reliability of ERS-PSRs. The case studies also examine the effects of the ratio of EVs with dynamic charging, wind generation penetration rate, additional wind power, and battery energy storage systems(BESSs) on the reliability of ERS-PSRs.展开更多
The real-time path optimization for heterogeneous vehicle fleets in large-scale road networks presents significant challenges due to conflicting traffic demands and imbalanced resource allocation.While existing vehicl...The real-time path optimization for heterogeneous vehicle fleets in large-scale road networks presents significant challenges due to conflicting traffic demands and imbalanced resource allocation.While existing vehicleto-infrastructure coordination frameworks partially address congestion mitigation,they often neglect priority-aware optimization and exhibit algorithmic bias toward dominant vehicle classes—critical limitations in mixed-priority scenarios involving emergency vehicles.To bridge this gap,this study proposes a preference game-theoretic coordination framework with adaptive strategy transfer protocol,explicitly balancing system-wide efficiency(measured by network throughput)with priority vehicle rights protection(quantified via time-sensitive utility functions).The approach innovatively combines(1)a multi-vehicle dynamic routing model with quantifiable preference weights,and(2)a distributed Nash equilibrium solver updated using replicator sub-dynamic models.The framework was evaluated on an urban road network containing 25 intersections with mixed priority ratios(10%–30%of vehicles with priority access demand),and the framework showed consistent benefits on four benchmarks(Social routing algorithm,Shortest path algorithm,The comprehensive path optimisation model,The emergency vehicle timing collaborative evolution path optimization method)showed consistent benefits.Results showthat across different traffic demand configurations,the proposed method reduces the average vehicle traveling time by at least 365 s,increases the road network throughput by 48.61%,and effectively balances the road loads.This approach successfully meets the diverse traffic demands of various vehicle types while optimizing road resource allocations.The proposed coordination paradigm advances theoretical foundations for fairness-aware traffic optimization while offering implementable strategies for next-generation cooperative vehicle-road systems,particularly in smart city deployments requiring mixed-priority mobility guarantees.展开更多
Metok,located in Nyingchi,the Xizang Autonomous Region,is known as the last county in China to be connected by road.Poor transportation and limited access to petroleum were two obstacles to its development.As soon as ...Metok,located in Nyingchi,the Xizang Autonomous Region,is known as the last county in China to be connected by road.Poor transportation and limited access to petroleum were two obstacles to its development.As soon as the highway connecting Metok and the outside world was completed in 2014,China National Petroleum Corporation’s(CNPC)first gas station in the county was put into operation,providing the momentum for this"secret land of Lotus"and helping it embark on a journey toward openness and prosperity.展开更多
Aerodynamic research on road cars was reviewed in this work under the thread of reducing drag,with the awareness that this may succeed in effectively decreasing the carbon footprint of transportation.First,a selection...Aerodynamic research on road cars was reviewed in this work under the thread of reducing drag,with the awareness that this may succeed in effectively decreasing the carbon footprint of transportation.First,a selection of studies was presented to focus on the most important aerodynamic features of the flow around realistic car body shapes.Then,the discussion was organized around three pillars related to passive flow control,active flow control and active aerodynamics.Both experimental and numerical investigations were included to provide a comprehensive overview.A clear distinction was made between simplified and realistic car models,as well as production vehicles(within the limits of restricted access information).Moreover,a short essay was dedicated to electric vehicles,for which aerodynamics matters,especially at highway speeds.Last,the impact of aerodynamic principles on the design of current and future vehicle fleet was assessed,honestly admitting that recent market trends must be reversed to turn decarbonization goals into reality and damp the effects of global warming.展开更多
Urban traffic generates massive and diverse data,yet most systems remain fragmented.Current approaches to congestion management suffer from weak data consistency and poor scalability.This study addresses this gap by p...Urban traffic generates massive and diverse data,yet most systems remain fragmented.Current approaches to congestion management suffer from weak data consistency and poor scalability.This study addresses this gap by proposing the Urban Traffic Congestion Unified Metadata Model(UTC-UMM).The goal is to provide a standardized and extensible framework for describing,extracting,and storing multisource traffic data in smart cities.The model defines a two-tier specification that organizes nine core traffic resource classes.It employs an eXtensible Markup Language(XML)Schema that connects general elements with resource-specific elements.This design ensures both syntactic and semantic interoperability across siloed datasets.Extension principles allow new elements or constraints to be introducedwithout breaking backward compatibility.Adistributed pipeline is implemented usingHadoop Distributed File System(HDFS)and HBase.It integrates computer vision for video and natural language processing for text to automate metadata extraction.Optimized row-key designs enable low-latency queries.Performance is tested with the Yahoo!Cloud Serving Benchmark(YCSB),which shows linear scalability and high throughput.The results demonstrate that UTC-UMM can unify heterogeneous traffic data while supporting real-time analytics.The discussion highlights its potential to improve data reuse,portability,and scalability in urban congestion studies.Future research will explore integration with association rulemining and advanced knowledge representation to capture richer spatiotemporal traffic patterns.展开更多
Global climate change is intensifying the impact of slope hazards,particularly rainfall-induced landslide hazards(RILH),on mountain road networks(MRNs).However,effective quantitative models for dynamically assessing M...Global climate change is intensifying the impact of slope hazards,particularly rainfall-induced landslide hazards(RILH),on mountain road networks(MRNs).However,effective quantitative models for dynamically assessing MRNs vulnerability under RILH disturbances are still lacking.To bridge this gap,this study develops a Cascading Failure Model for Rainfall-Induced Landslide Hazard(CFM-RILH).Validation via a case study of the GarzêTibetan Autonomous Prefecture Road Network(GTPRNs)reveals key characteristics of MRNs system vulnerability under RILH disturbances:(1)Under the disturbance effects of RILH,the vulnerability of the MRNs system follows a nonlinear phase transition law that intensifies with increasing disturbance intensity,exhibiting a distinct critical threshold.When the disturbance intensity exceeds this threshold,the system undergoes a global cascading failure phenomenon analogous to an“avalanche.”(2)Under RILH disturbances,the robustness of the MRNs system possesses a distinct safety boundary.Exceeding this boundary not only fails to improve hazard resistance but instead substantially elevates the risk of large-scale cascading failure.(3)Increasing network redundancy may be considered one of the primary engineering measures for enhancing MRNs resilience against such disturbances.Based on these findings,we propose a“Two-Stage Emergency Response and Hierarchical Fortification”strategy specifically to improve the resilience of GTPRNs impacted by RILH.The CFM-RILH model provides an effective tool for assessing road network vulnerability under such hazards.Furthermore,its modeling framework can also inform vulnerability assessment and resilience strategy development for road networks affected by other types of slope hazards.展开更多
In order to give a new way for modeling driving behavior, identifying road traffic accident causation and solving a variety of road traffic safety problems such as driving errors prevention and driving behavior analys...In order to give a new way for modeling driving behavior, identifying road traffic accident causation and solving a variety of road traffic safety problems such as driving errors prevention and driving behavior analysis, a new driving behavior shaping model is proposed, which could be used to assess the degree of effect of driving error upon road traffic safety. Driver behavior shaping model based on driving reliability and safety analysis could be used to identify the road traffic accident causation, to supply data for driver's behavior training, to evaluate driving procedures, to human factor design of road traffic system.展开更多
The electric road system(ERS)is an emerging technology to support decarbonization of heavy goods vehicles.The reliability of the traction power supply system(TPSS)for an electric road is a key consideration in ERS pla...The electric road system(ERS)is an emerging technology to support decarbonization of heavy goods vehicles.The reliability of the traction power supply system(TPSS)for an electric road is a key consideration in ERS planning and maintenance,but since the development of ERS is still at its early stage,the reliability study of different ERS systems has not been fully researched.This paper fills this research gap.It first analyses the potential operation risks of three different ERS systems using the failure mode and effect analysis method.Then,a fault tree model is built to analyse the overall reliability of the traction power supply system of each of the three ERS types and to identify the weak links.Furthermore,the overall failure rate and reliability indicators are obtained by combining the possible failures of both the electric and non-electric components of the TPSS.Finally,based on the analysis of the potential risks and the corresponding reliability indicators,the advantages and disadvantages of different ERS solutions and the future development prospects are discussed.展开更多
Poor road conditions in underground mine tunnels can lead to decreased production efficiency and increased wear on production vehicles. A prototype system for road condition monitoring is presented in this paper to co...Poor road conditions in underground mine tunnels can lead to decreased production efficiency and increased wear on production vehicles. A prototype system for road condition monitoring is presented in this paper to counteract this. The system consists of three components i.e. localization, road monitoring, and scheduling. The localization of vehicles is performed using a Rao-Blackwellized extended particle filter, combining vehicle mounted sensors with signal strengths of Wi Fi access points. Two methods for road monitoring are described: a Kalman filter used together with a model of the vehicle suspension system, and a relative condition measure based on the power spectral density. Lastly, a method for taking automatic action on an ill-conditioned road segment is proposed in the form of a rescheduling algorithm.The scheduling algorithm is based on the large neighborhood search and is used to integrate road service activities in the short-term production schedule while minimizing introduced production disturbances.The system is demonstrated on experimental data collected in a Swedish underground mine.展开更多
The expressway is necessary for the development of the modern transportation industry, and the level of expressway construction reflects the overall grade of national or regional economic development. In order to proc...The expressway is necessary for the development of the modern transportation industry, and the level of expressway construction reflects the overall grade of national or regional economic development. In order to process the expressway road property data information, based on the current mainstream Windows operating system, this study utilizes Geographic Information System (GIS) development technology, road video processing technology, and spatial data mining method to design and develop an expressway video and road infostructure GIS data production system. The system designs a multi-layer distributed application model in accordance with the ideas and methods of GIS engineering and the characteristics of road production data. In addition, according to the characteristics and specification requirements of basic geographic data, the road production database of spatial data and attribute data integrated storage is constructed by combining database and spatial data engine. Through the development of the GIS data production system for expressway video and road infostructure, various functions such as generation of road property data, dynamic management of road infostructure, and visualization of spatial information have been realized. The system focuses on improving the production efficiency and automation level of expressway production data and meet</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> the construction requirements for modernization, informatization, and intelligence of expressways.展开更多
Based on the vehicle-road dynamic model, the road characteristic parameter, which depends on different types of road surfaces, is introduced and a new method of road surface identification for automotive anti-lock bra...Based on the vehicle-road dynamic model, the road characteristic parameter, which depends on different types of road surfaces, is introduced and a new method of road surface identification for automotive anti-lock braking system (ABS) is proposed. According to the characteristics of vehicle-road dynamic model, a simple math resolution method of the model's factors is established. Only using the information of wheel speed, the vehicle reference velocity and the wheel slip ratio are estimated real-timely. And based on the wheel dynamic model, the road characteristic parameter is determined to identify the road surface for the determination of thresholds of ABS regulative parameters. With this new method, the road surface identification can be accurately obtained and calculation time is short that it can meet the ABS real time control need, and it also improves the performance of ABS.展开更多
The technique of incremental updating,which can better guarantee the real-time situation of navigational map,is the developing orientation of navigational road network updating.The data center of vehicle navigation sy...The technique of incremental updating,which can better guarantee the real-time situation of navigational map,is the developing orientation of navigational road network updating.The data center of vehicle navigation system is in charge of storing incremental data,and the spatio-temporal data model for storing incremental data does affect the efficiency of the response of the data center to the requirements of incremental data from the vehicle terminal.According to the analysis on the shortcomings of several typical spatio-temporal data models used in the data center and based on the base map with overlay model,the reverse map with overlay model (RMOM) was put forward for the data center to make rapid response to incremental data request.RMOM supports the data center to store not only the current complete road network data,but also the overlays of incremental data from the time when each road network changed to the current moment.Moreover,the storage mechanism and index structure of the incremental data were designed,and the implementation algorithm of RMOM was developed.Taking navigational road network in Guangzhou City as an example,the simulation test was conducted to validate the efficiency of RMOM.Results show that the navigation database in the data center can response to the requirements of incremental data by only one query with RMOM,and costs less time.Compared with the base map with overlay model,the data center does not need to temporarily overlay incremental data with RMOM,so time-consuming of response is significantly reduced.RMOM greatly improves the efficiency of response and provides strong support for the real-time situation of navigational road network.展开更多
Building a Green Silk Road by integrating the Sustainable Development Goals(SDGs) is one of the Belt and Road Initiative(BRI) visions, but the BRI faces enormous challenge that is the conflict between economic develop...Building a Green Silk Road by integrating the Sustainable Development Goals(SDGs) is one of the Belt and Road Initiative(BRI) visions, but the BRI faces enormous challenge that is the conflict between economic development and ecological sustainability.Understanding the current scale and trend of the impact of human activities on the ecosystem is the preliminary work to ensure that human activities do not exceed the ecological carrying capacity under the BRI. This study evaluated the ecosystem pressure in countries along the Belt and Road(B&R) from 2000–2017 based on the supply-consumption balance relationship of ecological resources. Net primary productivity(NPP) is taken as the measure of ecological resources, and the supply level and consumption intensity of ecological resources is estimated based on remote sensing data and statistical data, respectively. Results show that thirteen countries with overconsumed ecological resources concentrated in the West Asia/Middle East. Although the intensity of the ecological resource consumption correlated with ecological resource endowments, the ecosystem pressure was determined by social development dependence on the ecological resources at the same ecological resource endowments level. Nearly 80% of countries along the B&R suffered from significantly increased(P < 0.05) ecosystem pressure during 2000–2017, since most of the countries along the B&R were developing countries,and their economic development was highly dependent on ecological resources. Some West Asia/Middle East countries successfully mitigated the ecosystem pressure by importing feed for livestock. Likewise, the Southeast Asian islands benefitted from the import of agricultural products. The results highlight that the BRI should reduce the dependence of social development demands on local ecological resources by international trade for ensuring the increasing ecosystem pressure trend within the ecological carrying capacity.展开更多
Road marking detection is an important branch in autonomous driving,understanding the road information.In recent years,deep-learning-based semantic segmentation methods for road marking detection have been arising sin...Road marking detection is an important branch in autonomous driving,understanding the road information.In recent years,deep-learning-based semantic segmentation methods for road marking detection have been arising since they can generalize detection result well under complicated environments and hold rich pixel-level semantic information.Nevertheless,the previous methods mostly study the training process of the segmentation network,while omitting the time cost of manually annotating pixel-level data.Besides,the pixel-level semantic segmentation results need to be fitted into more reliable and compact models so that geometrical information of road markings can be explicitly obtained.In order to tackle the above problems,this paper describes a semantic segmentation-based road marking detection method using around view monitoring system.A semiautomatic semantic annotation platform is developed,which exploits an auxiliary segmentation graph to speed up the annotation process while guaranteeing the annotation accuracy.A segmentation-based detection module is also described,which models the semantic segmentation results for the more robust and compact analysis.The proposed detection module is composed of three parts:vote-based segmentation fusion filtering,graph-based road marking clustering,and road-marking fitting.Experiments under various scenarios show that the semantic segmentation-based detection method can achieve accurate,robust,and real-time detection performance.展开更多
Ancient Sichuan Salt Road(the ancient road for the transportation of Sichuan salt) is a cultural route characterized by salt transportation culture in southwest and central-west China, along which a large number of di...Ancient Sichuan Salt Road(the ancient road for the transportation of Sichuan salt) is a cultural route characterized by salt transportation culture in southwest and central-west China, along which a large number of diversifi ed and systematic cultural heritages have been left, including both tangible and intangible salt transportation cultural heritages such as ancient salt transportation road, salt shop, post house, stele inscription, ancient town, ancient bridge, guild hal, and boatmen's work songs. With the rapid economic and social development, the accelerating modernization and urbanization, and also drastic changes of traffi c environment have contributed to the endangered situation of ancient Sichuan salt road cultural heritage. In face of such problems as lack of coordinated protection mechanism, destructive development, backward protection of cultural relics, and inheritance risks of intangible heritage, cultural heritages along the ancient Sichuan salt road should be protected by establishing a protection mechanism, organizing the coordinated actions of local areas along the road, investigating and rescuing cultural heritage in time, and enhancing the cooperative research. In view of the complicate and long-term nature of protecting linear cultural heritage, successful experience of domestic and foreign cultural route heritage management can be learned, salt transportation cultural heritage protection, tourism planning and development of ancient Sichuan salt road should be considered, protection of the ancient salt road should be combined with economic, social and cultural development of regions along the road, so as to explore an effective mode for the protection, development and management of large-scale linear cultural heritages consisting of both land and water routes.展开更多
文摘This paper analyses the overall landscape framework of city road system in ancient and modern China, using the ideal state terrain model which was fi rst recorded by the construction system of the Zhou Dynasty, and summarizes the ideal model of overall landscape framework of city road system, based on Chinese psychological needs of landscape, and conducts the applied research taking Nanchong in Sichuan, China for example.
基金Supported by Fund Project of Scientific Research of Zhongkai University of Agriculture and Engineering(G3071201)~~
文摘Based on the idea of system,the paper had analyzed components of garden road system in urban park and their relations from the perspective of function,pattern and facility,and established framework of garden road system for guidance of garden road construction.After introduction of the connotation of garden road system,its attributes were summarized which were isolated elements,integrated collection,clear level and dynamic development;and its functional composition had been concluded from the aspects of practical function and social function.Practical functions contained traffic organization and guidance tour,space division and landscape composition,facility organization and habitat improvement.Social functions consisted of communication and education function.The pattern of garden road system had been introduced in terms of pattern elements,level structure and layout form.Facilities of garden road system had been classified into five categories covering rest facilities,ornamental facilities,light facilities,display facilities and service facilities.
基金Under the auspices of National Natural Science Foundation of China(No.41430638)Special Found for Beijing Common Construction Project for Beijing Laboratory of Urban and Rural Ecological Environment(No.PXM2015_014207_000014)Grants from the Beijing Municipal Education Commission(No.PXM2019_014207_000099)
文摘Particulate matter(PM), one of the most important pollutants of traffic emission, threatens the health of urban ecosystems and citizens. Roadside trees play an important role in trapping PM, and the foliar PM load is a useful indicator for air PM pollution in road systems. To detect the relationships of foliar PM load with road structures, urbanization, and meteorology in road systems, we studied a widely-planted tree Sophora japonica L. in 100 roads and 10 yards of Beijing, China, and found that the foliar PM loads increased with the distances from the urban centre(DUC) linearly, while decreased with the road density. All-subsets regression analysis indicated that DUC, average monthly relative humidity, average monthly wind speed, and mean annual wind speed were the most important factors in predicting foliar PM load, rather than general situation of buildings and road cleanliness. The monthly relative humidity and monthly wind speed had a negative correlation to foliar PM, while the annual relative humidity and annual wind speed had a positive correlation to foliar PM. Suburban areas and these effective factors should be highlighted in PM control in Beijing.
文摘The rapid development of the automobile industry and the relative lag of the road construction have constituted a prominent contradiction all over the world, particularly, in most of large cities. To cope with it, elevated roads have been built in many cities both at home and abroad. However, traffic jams frequently appear on elevated roads immediately after the completion of their construction. The awkward situation mainly results from the planning bug or the unsuitable control, apart from drastic increase in transportation demand. Elevated roads,
文摘In order to eliminate the difficulties caused by the presence of snow and ice on the road surface and to create a safe, constant and convenient movement with their design speeds and loads, companies and organizations should apply a set of roads winter maintenance activities. Drifted snow on the roads is determined by a group of factors, which in most cases depend on each other and occur in different combinations. The main factors are: the climate conditions, the specific features of the area, the geometric and constructive elements of the road.
基金supported by the China Scholarship Council(No.202006130002).
文摘With the rapid expansion of urban road networks and the increasing ownership of vehicles in many countries and regions, the greenhouse gas and pollutant emissions from road travels have become a global concern. The introduction of electric vehicles(EVs) with dynamic charging into road systems, which is defined as electric road systems(ERSs), has been widely recognized as a viable solution to address this problem. This paper presents a comprehensive study on the reliability of power supply systems integrated with renewables for ERS(ERSPSRs), which interface with both road traffic and power networks. First, a brief introduction to the charging modes of EVs demonstrates the coupling of the two networks. A simplified traffic model is then built, based on which the reliability indices of the system considering the influence of the dynamic charging and static charging modes of EVs are proposed. Further, a simplified trip chain based Monte Carlo reliability assessment method of ERS-PSRs is proposed. Case studies based on the IEEE Roy Billinton Test System(RBTS) show that the dynamic charging mode of EVs can not only effectively balance the supply and demand of the power grid at different time(shaving peaks and filling valleys), but also significantly improve the reliability of ERS-PSRs. The case studies also examine the effects of the ratio of EVs with dynamic charging, wind generation penetration rate, additional wind power, and battery energy storage systems(BESSs) on the reliability of ERS-PSRs.
基金funded by the National Key Research and Development Program Project 2022YFB4300404.
文摘The real-time path optimization for heterogeneous vehicle fleets in large-scale road networks presents significant challenges due to conflicting traffic demands and imbalanced resource allocation.While existing vehicleto-infrastructure coordination frameworks partially address congestion mitigation,they often neglect priority-aware optimization and exhibit algorithmic bias toward dominant vehicle classes—critical limitations in mixed-priority scenarios involving emergency vehicles.To bridge this gap,this study proposes a preference game-theoretic coordination framework with adaptive strategy transfer protocol,explicitly balancing system-wide efficiency(measured by network throughput)with priority vehicle rights protection(quantified via time-sensitive utility functions).The approach innovatively combines(1)a multi-vehicle dynamic routing model with quantifiable preference weights,and(2)a distributed Nash equilibrium solver updated using replicator sub-dynamic models.The framework was evaluated on an urban road network containing 25 intersections with mixed priority ratios(10%–30%of vehicles with priority access demand),and the framework showed consistent benefits on four benchmarks(Social routing algorithm,Shortest path algorithm,The comprehensive path optimisation model,The emergency vehicle timing collaborative evolution path optimization method)showed consistent benefits.Results showthat across different traffic demand configurations,the proposed method reduces the average vehicle traveling time by at least 365 s,increases the road network throughput by 48.61%,and effectively balances the road loads.This approach successfully meets the diverse traffic demands of various vehicle types while optimizing road resource allocations.The proposed coordination paradigm advances theoretical foundations for fairness-aware traffic optimization while offering implementable strategies for next-generation cooperative vehicle-road systems,particularly in smart city deployments requiring mixed-priority mobility guarantees.
文摘Metok,located in Nyingchi,the Xizang Autonomous Region,is known as the last county in China to be connected by road.Poor transportation and limited access to petroleum were two obstacles to its development.As soon as the highway connecting Metok and the outside world was completed in 2014,China National Petroleum Corporation’s(CNPC)first gas station in the county was put into operation,providing the momentum for this"secret land of Lotus"and helping it embark on a journey toward openness and prosperity.
文摘Aerodynamic research on road cars was reviewed in this work under the thread of reducing drag,with the awareness that this may succeed in effectively decreasing the carbon footprint of transportation.First,a selection of studies was presented to focus on the most important aerodynamic features of the flow around realistic car body shapes.Then,the discussion was organized around three pillars related to passive flow control,active flow control and active aerodynamics.Both experimental and numerical investigations were included to provide a comprehensive overview.A clear distinction was made between simplified and realistic car models,as well as production vehicles(within the limits of restricted access information).Moreover,a short essay was dedicated to electric vehicles,for which aerodynamics matters,especially at highway speeds.Last,the impact of aerodynamic principles on the design of current and future vehicle fleet was assessed,honestly admitting that recent market trends must be reversed to turn decarbonization goals into reality and damp the effects of global warming.
基金supported by the National Natural Science Foundation of China(Grant No.62172033).
文摘Urban traffic generates massive and diverse data,yet most systems remain fragmented.Current approaches to congestion management suffer from weak data consistency and poor scalability.This study addresses this gap by proposing the Urban Traffic Congestion Unified Metadata Model(UTC-UMM).The goal is to provide a standardized and extensible framework for describing,extracting,and storing multisource traffic data in smart cities.The model defines a two-tier specification that organizes nine core traffic resource classes.It employs an eXtensible Markup Language(XML)Schema that connects general elements with resource-specific elements.This design ensures both syntactic and semantic interoperability across siloed datasets.Extension principles allow new elements or constraints to be introducedwithout breaking backward compatibility.Adistributed pipeline is implemented usingHadoop Distributed File System(HDFS)and HBase.It integrates computer vision for video and natural language processing for text to automate metadata extraction.Optimized row-key designs enable low-latency queries.Performance is tested with the Yahoo!Cloud Serving Benchmark(YCSB),which shows linear scalability and high throughput.The results demonstrate that UTC-UMM can unify heterogeneous traffic data while supporting real-time analytics.The discussion highlights its potential to improve data reuse,portability,and scalability in urban congestion studies.Future research will explore integration with association rulemining and advanced knowledge representation to capture richer spatiotemporal traffic patterns.
基金financially supported by the National Key R&D Program of China(2024YFE0111900)The National Natural Science Foundation of China(U2468214,52378370,52278372)+1 种基金The National Ten Thousand Talent Program for Young Top-notch Talents(2022QB04978)The Science and Technology Program of Hebei Province(2023HBQZYCSB004)。
文摘Global climate change is intensifying the impact of slope hazards,particularly rainfall-induced landslide hazards(RILH),on mountain road networks(MRNs).However,effective quantitative models for dynamically assessing MRNs vulnerability under RILH disturbances are still lacking.To bridge this gap,this study develops a Cascading Failure Model for Rainfall-Induced Landslide Hazard(CFM-RILH).Validation via a case study of the GarzêTibetan Autonomous Prefecture Road Network(GTPRNs)reveals key characteristics of MRNs system vulnerability under RILH disturbances:(1)Under the disturbance effects of RILH,the vulnerability of the MRNs system follows a nonlinear phase transition law that intensifies with increasing disturbance intensity,exhibiting a distinct critical threshold.When the disturbance intensity exceeds this threshold,the system undergoes a global cascading failure phenomenon analogous to an“avalanche.”(2)Under RILH disturbances,the robustness of the MRNs system possesses a distinct safety boundary.Exceeding this boundary not only fails to improve hazard resistance but instead substantially elevates the risk of large-scale cascading failure.(3)Increasing network redundancy may be considered one of the primary engineering measures for enhancing MRNs resilience against such disturbances.Based on these findings,we propose a“Two-Stage Emergency Response and Hierarchical Fortification”strategy specifically to improve the resilience of GTPRNs impacted by RILH.The CFM-RILH model provides an effective tool for assessing road network vulnerability under such hazards.Furthermore,its modeling framework can also inform vulnerability assessment and resilience strategy development for road networks affected by other types of slope hazards.
文摘In order to give a new way for modeling driving behavior, identifying road traffic accident causation and solving a variety of road traffic safety problems such as driving errors prevention and driving behavior analysis, a new driving behavior shaping model is proposed, which could be used to assess the degree of effect of driving error upon road traffic safety. Driver behavior shaping model based on driving reliability and safety analysis could be used to identify the road traffic accident causation, to supply data for driver's behavior training, to evaluate driving procedures, to human factor design of road traffic system.
基金funded by the China Scholarship Council,which sponsored Wei Zuo’s PhD study at the University of Leeds。
文摘The electric road system(ERS)is an emerging technology to support decarbonization of heavy goods vehicles.The reliability of the traction power supply system(TPSS)for an electric road is a key consideration in ERS planning and maintenance,but since the development of ERS is still at its early stage,the reliability study of different ERS systems has not been fully researched.This paper fills this research gap.It first analyses the potential operation risks of three different ERS systems using the failure mode and effect analysis method.Then,a fault tree model is built to analyse the overall reliability of the traction power supply system of each of the three ERS types and to identify the weak links.Furthermore,the overall failure rate and reliability indicators are obtained by combining the possible failures of both the electric and non-electric components of the TPSS.Finally,based on the analysis of the potential risks and the corresponding reliability indicators,the advantages and disadvantages of different ERS solutions and the future development prospects are discussed.
基金partially supported by the Wallenberg AIAutonomous Systems and Software Program (WASP) funded by the Knut and Alice Wallenberg Foundation
文摘Poor road conditions in underground mine tunnels can lead to decreased production efficiency and increased wear on production vehicles. A prototype system for road condition monitoring is presented in this paper to counteract this. The system consists of three components i.e. localization, road monitoring, and scheduling. The localization of vehicles is performed using a Rao-Blackwellized extended particle filter, combining vehicle mounted sensors with signal strengths of Wi Fi access points. Two methods for road monitoring are described: a Kalman filter used together with a model of the vehicle suspension system, and a relative condition measure based on the power spectral density. Lastly, a method for taking automatic action on an ill-conditioned road segment is proposed in the form of a rescheduling algorithm.The scheduling algorithm is based on the large neighborhood search and is used to integrate road service activities in the short-term production schedule while minimizing introduced production disturbances.The system is demonstrated on experimental data collected in a Swedish underground mine.
文摘The expressway is necessary for the development of the modern transportation industry, and the level of expressway construction reflects the overall grade of national or regional economic development. In order to process the expressway road property data information, based on the current mainstream Windows operating system, this study utilizes Geographic Information System (GIS) development technology, road video processing technology, and spatial data mining method to design and develop an expressway video and road infostructure GIS data production system. The system designs a multi-layer distributed application model in accordance with the ideas and methods of GIS engineering and the characteristics of road production data. In addition, according to the characteristics and specification requirements of basic geographic data, the road production database of spatial data and attribute data integrated storage is constructed by combining database and spatial data engine. Through the development of the GIS data production system for expressway video and road infostructure, various functions such as generation of road property data, dynamic management of road infostructure, and visualization of spatial information have been realized. The system focuses on improving the production efficiency and automation level of expressway production data and meet</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> the construction requirements for modernization, informatization, and intelligence of expressways.
文摘Based on the vehicle-road dynamic model, the road characteristic parameter, which depends on different types of road surfaces, is introduced and a new method of road surface identification for automotive anti-lock braking system (ABS) is proposed. According to the characteristics of vehicle-road dynamic model, a simple math resolution method of the model's factors is established. Only using the information of wheel speed, the vehicle reference velocity and the wheel slip ratio are estimated real-timely. And based on the wheel dynamic model, the road characteristic parameter is determined to identify the road surface for the determination of thresholds of ABS regulative parameters. With this new method, the road surface identification can be accurately obtained and calculation time is short that it can meet the ABS real time control need, and it also improves the performance of ABS.
基金Under the auspices of National High Technology Research and Development Program of China (No.2007AA12Z242)
文摘The technique of incremental updating,which can better guarantee the real-time situation of navigational map,is the developing orientation of navigational road network updating.The data center of vehicle navigation system is in charge of storing incremental data,and the spatio-temporal data model for storing incremental data does affect the efficiency of the response of the data center to the requirements of incremental data from the vehicle terminal.According to the analysis on the shortcomings of several typical spatio-temporal data models used in the data center and based on the base map with overlay model,the reverse map with overlay model (RMOM) was put forward for the data center to make rapid response to incremental data request.RMOM supports the data center to store not only the current complete road network data,but also the overlays of incremental data from the time when each road network changed to the current moment.Moreover,the storage mechanism and index structure of the incremental data were designed,and the implementation algorithm of RMOM was developed.Taking navigational road network in Guangzhou City as an example,the simulation test was conducted to validate the efficiency of RMOM.Results show that the navigation database in the data center can response to the requirements of incremental data by only one query with RMOM,and costs less time.Compared with the base map with overlay model,the data center does not need to temporarily overlay incremental data with RMOM,so time-consuming of response is significantly reduced.RMOM greatly improves the efficiency of response and provides strong support for the real-time situation of navigational road network.
基金Under the auspices of the Strategic Priority Research Program of the Chinese Academy of Sciences (No.XDA20010202)Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDA19040301)。
文摘Building a Green Silk Road by integrating the Sustainable Development Goals(SDGs) is one of the Belt and Road Initiative(BRI) visions, but the BRI faces enormous challenge that is the conflict between economic development and ecological sustainability.Understanding the current scale and trend of the impact of human activities on the ecosystem is the preliminary work to ensure that human activities do not exceed the ecological carrying capacity under the BRI. This study evaluated the ecosystem pressure in countries along the Belt and Road(B&R) from 2000–2017 based on the supply-consumption balance relationship of ecological resources. Net primary productivity(NPP) is taken as the measure of ecological resources, and the supply level and consumption intensity of ecological resources is estimated based on remote sensing data and statistical data, respectively. Results show that thirteen countries with overconsumed ecological resources concentrated in the West Asia/Middle East. Although the intensity of the ecological resource consumption correlated with ecological resource endowments, the ecosystem pressure was determined by social development dependence on the ecological resources at the same ecological resource endowments level. Nearly 80% of countries along the B&R suffered from significantly increased(P < 0.05) ecosystem pressure during 2000–2017, since most of the countries along the B&R were developing countries,and their economic development was highly dependent on ecological resources. Some West Asia/Middle East countries successfully mitigated the ecosystem pressure by importing feed for livestock. Likewise, the Southeast Asian islands benefitted from the import of agricultural products. The results highlight that the BRI should reduce the dependence of social development demands on local ecological resources by international trade for ensuring the increasing ecosystem pressure trend within the ecological carrying capacity.
基金the National Natural Science Foundation of China(Nos.U1764264 and 61873165)the Shanghai Automotive Industry Science and Technology Development Foundation(No.1807)。
文摘Road marking detection is an important branch in autonomous driving,understanding the road information.In recent years,deep-learning-based semantic segmentation methods for road marking detection have been arising since they can generalize detection result well under complicated environments and hold rich pixel-level semantic information.Nevertheless,the previous methods mostly study the training process of the segmentation network,while omitting the time cost of manually annotating pixel-level data.Besides,the pixel-level semantic segmentation results need to be fitted into more reliable and compact models so that geometrical information of road markings can be explicitly obtained.In order to tackle the above problems,this paper describes a semantic segmentation-based road marking detection method using around view monitoring system.A semiautomatic semantic annotation platform is developed,which exploits an auxiliary segmentation graph to speed up the annotation process while guaranteeing the annotation accuracy.A segmentation-based detection module is also described,which models the semantic segmentation results for the more robust and compact analysis.The proposed detection module is composed of three parts:vote-based segmentation fusion filtering,graph-based road marking clustering,and road-marking fitting.Experiments under various scenarios show that the semantic segmentation-based detection method can achieve accurate,robust,and real-time detection performance.
基金Sponsored by Bidding Project of China Salt Culture Research Center,Sichuan University of Science&Engineering,Key Research Base of Sichuan Provincial Philosophy and Social Sciences(YWHZB14-01)2015 Planning Program of Zigong Municipal Philosophy and Social Sciences
文摘Ancient Sichuan Salt Road(the ancient road for the transportation of Sichuan salt) is a cultural route characterized by salt transportation culture in southwest and central-west China, along which a large number of diversifi ed and systematic cultural heritages have been left, including both tangible and intangible salt transportation cultural heritages such as ancient salt transportation road, salt shop, post house, stele inscription, ancient town, ancient bridge, guild hal, and boatmen's work songs. With the rapid economic and social development, the accelerating modernization and urbanization, and also drastic changes of traffi c environment have contributed to the endangered situation of ancient Sichuan salt road cultural heritage. In face of such problems as lack of coordinated protection mechanism, destructive development, backward protection of cultural relics, and inheritance risks of intangible heritage, cultural heritages along the ancient Sichuan salt road should be protected by establishing a protection mechanism, organizing the coordinated actions of local areas along the road, investigating and rescuing cultural heritage in time, and enhancing the cooperative research. In view of the complicate and long-term nature of protecting linear cultural heritage, successful experience of domestic and foreign cultural route heritage management can be learned, salt transportation cultural heritage protection, tourism planning and development of ancient Sichuan salt road should be considered, protection of the ancient salt road should be combined with economic, social and cultural development of regions along the road, so as to explore an effective mode for the protection, development and management of large-scale linear cultural heritages consisting of both land and water routes.
