Starting JPom a low level China's rapid urOamzatlon ttas talcen on a targe scale over the past three decades. The urbanization of urban clusters has become a key driver of China's economic development. However, Chin...Starting JPom a low level China's rapid urOamzatlon ttas talcen on a targe scale over the past three decades. The urbanization of urban clusters has become a key driver of China's economic development. However, China's urbanization has been confronted with many issues, such as high resource and environmental costs, low level of citizenship for migrant workers, strong economic polarization and excessive dependence on land encroachment. In the near future, China's urbanization will enter a period of strategic transitioning, and the enhancement of the quality of urbanization will become a strategic priority. China's urbanization rate is projected to reach 60% by 2020 and 68% by 2030, eventually exceeding 80% by 2050. China's future urbanization must proceed from local realities, promote the balanced development of small, medium-sized and large cities and towns, optimize the spatial layout of urbanization, and follow a sensible pattern.展开更多
Mobile multimedia streaming is an open topic in vehicular environment. Due to the high intermittent links, it has become a critical challenge to deliver high quality video streaming in vehicular networks. In this pape...Mobile multimedia streaming is an open topic in vehicular environment. Due to the high intermittent links, it has become a critical challenge to deliver high quality video streaming in vehicular networks. In this paper, we reform the Information Centric Networking (ICN) concept for multimedia delivery in urban vehicular networks. By leveraging the 1CN perspective, we highlight that vehicular peers can obtain multimedia chunks via the vehicle-to-cloud (V2C) approach to improve the delivery quality. Based on this, we propose a lightweight multipath selection strategy to guide the network system to adaptively adjust the forwarding means. Extensive simulations show that the proposed solution can optimize the utilization of network paths, lighten network loads as well as avoid wasting resources.展开更多
In this paper,computational models of environmental pollution and energy consumption of urban multimodal traffic network are proposed according to pertinent research and a multi-objective programming model is then dev...In this paper,computational models of environmental pollution and energy consumption of urban multimodal traffic network are proposed according to pertinent research and a multi-objective programming model is then developed to formulate optimization problem for such a system.Simultaneously,the main factors,such as travel time,pricing and convenience which influence travelers' choice behaviors are all considered and a combined assignment model is proposed to simulate travelers' mode and route choices.A bi-level programming model,in which the multi-objective optimization model is treated as the upper-level problem and the combined assignment model is processed as the lower-level problem,is then presented to solve multi-criterion system optimization problem for urban multimodal traffic network.The solution algorithms of the proposed models are also presented.Finally,the model and its algorithms are illustrated through a simple numerical example.展开更多
Multi-objective optimization of urban bus network can help improve operation efficiency of the transit system and develop strategies for reducing urban traffic congestion in China. The work used cumulative prospect th...Multi-objective optimization of urban bus network can help improve operation efficiency of the transit system and develop strategies for reducing urban traffic congestion in China. The work used cumulative prospect theory, currently the most influential model for decision under uncertainty,to optimize urban bus network. To achieve the research objective, the work developed the theoretical framework of urban bus network optimization, including optimization principle, optimization objectives and constraints. Furthermore, optimization objectives could comprehensively reflect expectations of passengers and bus companies from the dimension of time, space and value. It is more scientific and reasonable compared with only one stakeholder or dimension alone in the previous studies. In addition,the technique for order preference by similarity to ideal solution(TOPSIS) was used to determine the positive and negative ideal alternative. The correlations between the optimization alternatives and the ideal alternatives were estimated by grey relational analysis simultaneously. The cumulative prospect theory(CPT) was used to determine the best alternative by comparing comprehensive prospect value of every alternative, accurately describing decision-making behavior compared with expected utility theory in actual life. Finally, Case of Xi'an showed that the method can better adjust the bus network,and the optimization solution is more reasonable to meet the actual needs.展开更多
文摘Starting JPom a low level China's rapid urOamzatlon ttas talcen on a targe scale over the past three decades. The urbanization of urban clusters has become a key driver of China's economic development. However, China's urbanization has been confronted with many issues, such as high resource and environmental costs, low level of citizenship for migrant workers, strong economic polarization and excessive dependence on land encroachment. In the near future, China's urbanization will enter a period of strategic transitioning, and the enhancement of the quality of urbanization will become a strategic priority. China's urbanization rate is projected to reach 60% by 2020 and 68% by 2030, eventually exceeding 80% by 2050. China's future urbanization must proceed from local realities, promote the balanced development of small, medium-sized and large cities and towns, optimize the spatial layout of urbanization, and follow a sensible pattern.
基金partially supported by the Fundamental Research Funds for the Central Universities under Grant No.2015JBM009the National Natural Science Foundation of China(NSFC) under Grant 61602030 U1404611,61301081+1 种基金the Project Funded by China Postdoctoral Science Foundation under Grant No.2016T90031,2015M570028 and 2015M580970the Program for Science & Technology Innovation Talents in the University of Henan Province under Grant No.16HASTIT035
文摘Mobile multimedia streaming is an open topic in vehicular environment. Due to the high intermittent links, it has become a critical challenge to deliver high quality video streaming in vehicular networks. In this paper, we reform the Information Centric Networking (ICN) concept for multimedia delivery in urban vehicular networks. By leveraging the 1CN perspective, we highlight that vehicular peers can obtain multimedia chunks via the vehicle-to-cloud (V2C) approach to improve the delivery quality. Based on this, we propose a lightweight multipath selection strategy to guide the network system to adaptively adjust the forwarding means. Extensive simulations show that the proposed solution can optimize the utilization of network paths, lighten network loads as well as avoid wasting resources.
基金supported by the National Natural Science Foundation of China (Grant Nos. 71071016, 70901005)the Fundamental Research Funds for the Central Universities (Grant Nos. 2009JBM040 and 2009JBZ012)funded by a Discovery Grant (Application No. 342485-07) from the Natural Science and Engineering Research Council (NSERC), Canada
文摘In this paper,computational models of environmental pollution and energy consumption of urban multimodal traffic network are proposed according to pertinent research and a multi-objective programming model is then developed to formulate optimization problem for such a system.Simultaneously,the main factors,such as travel time,pricing and convenience which influence travelers' choice behaviors are all considered and a combined assignment model is proposed to simulate travelers' mode and route choices.A bi-level programming model,in which the multi-objective optimization model is treated as the upper-level problem and the combined assignment model is processed as the lower-level problem,is then presented to solve multi-criterion system optimization problem for urban multimodal traffic network.The solution algorithms of the proposed models are also presented.Finally,the model and its algorithms are illustrated through a simple numerical example.
基金supported by China’s National Key Basic Research Program under Grant No.2012CB725400China’s National Natural Science Fund Key Research Program under Grant No.51338003+2 种基金Key Cultivating Plan of Xi’an University of Architecture and Technology for Discipline Construction under Grant No.XK201213Talents Training Fund Program of Xi’an University of Architecture and Technology for Cultivating Discipline Construction under Grant No.XK201101Youth Talent Fund of Xi’an University of Architecture and Technology under Grant No.DB01138
文摘Multi-objective optimization of urban bus network can help improve operation efficiency of the transit system and develop strategies for reducing urban traffic congestion in China. The work used cumulative prospect theory, currently the most influential model for decision under uncertainty,to optimize urban bus network. To achieve the research objective, the work developed the theoretical framework of urban bus network optimization, including optimization principle, optimization objectives and constraints. Furthermore, optimization objectives could comprehensively reflect expectations of passengers and bus companies from the dimension of time, space and value. It is more scientific and reasonable compared with only one stakeholder or dimension alone in the previous studies. In addition,the technique for order preference by similarity to ideal solution(TOPSIS) was used to determine the positive and negative ideal alternative. The correlations between the optimization alternatives and the ideal alternatives were estimated by grey relational analysis simultaneously. The cumulative prospect theory(CPT) was used to determine the best alternative by comparing comprehensive prospect value of every alternative, accurately describing decision-making behavior compared with expected utility theory in actual life. Finally, Case of Xi'an showed that the method can better adjust the bus network,and the optimization solution is more reasonable to meet the actual needs.