针对现代城市复杂交通网络现状,提出以交通地理信息系统(transportation-geographic information system,T-GIS)数据模型来描述、城市复杂道路网络的复杂特性.首先以复杂网络理论验证城市道路网络的复杂特性,其次从道路网络综合描述属...针对现代城市复杂交通网络现状,提出以交通地理信息系统(transportation-geographic information system,T-GIS)数据模型来描述、城市复杂道路网络的复杂特性.首先以复杂网络理论验证城市道路网络的复杂特性,其次从道路网络综合描述属性表达和网络数据逻辑关系3个方面构建城市复杂道路网络T-GIS数据模型.实践证明,本T-GIS模型具有很好的应用效果,很好表达道路网络空间信息及复杂逻辑关系,为道路拥堵和路径诱导及城市道路网络演化研究提供所需数据,且具有较好的推广价值.展开更多
One of the most powerful functions of Geographic Information System for Transportation (GIS-T) is Dynamic Segmentation (DS), which is used to increase the efficiency and precision of road management by generating segm...One of the most powerful functions of Geographic Information System for Transportation (GIS-T) is Dynamic Segmentation (DS), which is used to increase the efficiency and precision of road management by generating segments based on attributes. The road segments describing transportation data are both spatially and temporally referenced. For a variety of transportation applications, historical road segments must be preserved. This study presents an appropriate approach to preserve and retrieve the historical road segments efficiently. In the proposed method, only the portions of segments of a time stamp that have been changed into new segments rather than storing the entire segments for every old time stamp are recorded .The storage of these portions is based on the type of changes. A recursive algorithm is developed to retrieve all segments for every old time stamp. Experimental results using real data of Tehran City, Iran justify the strength of the proposed approach in many aspects. An important achievement of the results is that database volume for 2006, 2007 and 2008 within the Historical Line Event Table (HLET) is reduced by 70%, 80% and 78%, respectively. The proposed method has the potential to prevent from vast data redundancy and the unnecessary storage of entire segments for each time stamp. Since the present technique is performed on ordinary plain tables that are readable by all GIS software, special software platforms to manage the storage and retrieval of historical segments are not needed. In addition, this method simplifies spatio-temporal queries.展开更多
Addressing transportation planning, operation and investment challenges requires increasingly sophisticated data and information management strategies. ITS (intelligent transportation systems) and CV (connected veh...Addressing transportation planning, operation and investment challenges requires increasingly sophisticated data and information management strategies. ITS (intelligent transportation systems) and CV (connected vehicle) technologies represent a new approach to capturing and using needed transportation data in real time or near real time. In the case of Michigan, several ITS programs have been launched successfully, but independently of each other. The objective of this research is to evaluate and assess all important factors that will influence the collection, management and use of ITS data, and recommend strategies to develop integrated, dynamic and adaptive data management systems for state transportation agencies.展开更多
This paper studies a routing protocol used in the application of collecting real-time traffic information using mobile vehicles to monitor traffic status. The biggest challenge of vehicular ad hoe network routing prot...This paper studies a routing protocol used in the application of collecting real-time traffic information using mobile vehicles to monitor traffic status. The biggest challenge of vehicular ad hoe network routing protocol lies in the mismatch between the direction of moving vehicles and routed data. In order to deal with this mismatch, a mesh based routing protocol with a two-tier network architecture is proposed. By using mesh nodes deployed at intersections, data can be routed through an optimized path which can improve the delivery ratio and reduce the consumption of network resources. The simulation uses the mobility model processed from the GPS data of taxis mnning in Shanghai urban areas. The result shows that the proposed protocol outperforms the existing flooding protocol.展开更多
WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System (ColTS). However, the mobility of...WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System (ColTS). However, the mobility of nodes makes data dissemination a hard nut to crack. In this paper, we propose MSDD, a multiple mobile sinks data dissemination mechanism for solving the dissemination problem. The main ideas of MSDD are constructing a two-tier grid structure by a designated sink, exploiting a hierarchical monitoring mechanism, and employing a global agent to track the sink locations in order to make the emergencies reported to the sinks immediately, In addition, MSDD supports the query-driven data dissemination. Being compared with TTDD, MSDD is theoretically proved to have less communication overhead. We also validate MSDD outperforms TTDD in reliability and the emergency delivery latency bv simulations.展开更多
This study explores the use of augmented reality smart glasses(ARSGs) by physicians and their adoption of these products in the Turkish medical industry.Google Glass was used as a demonstrative example for the introdu...This study explores the use of augmented reality smart glasses(ARSGs) by physicians and their adoption of these products in the Turkish medical industry.Google Glass was used as a demonstrative example for the introduction of ARSGs. We proposed an exploratory model based on the technology acceptance model by Davis. Exogenous factors in the model were defined by performing semi-structured in-depth interviews, along with the use of an expert panel in addition to the technology adoption literature. The framework was tested by means of a field study, data was collected via an Internet survey, and path analysis was used. The results indicate that there were a number of factors to be considered in order to understand ARSG adoption by physicians.Usefulness was influenced by ease of use, compatibility,ease of reminding, and speech recognition, while ease of use was affected by ease of learning, ease of medical education, external influence, and privacy. Privacy was the only negative factor that reduced the perceived ease of use,and was found to indirectly create a negative attitude.Compatibility emerged as the most significant external factor for usefulness. Developers of ARSGs should pay attention to healthcare-specific requirements for improved utilization and more extensive adoption of ARSGs in healthcare settings. In particular, they should focus on how to increase the compatibility of ARSGs. Further research needs to be conducted to explain the adoption intention of physicians.展开更多
文摘针对现代城市复杂交通网络现状,提出以交通地理信息系统(transportation-geographic information system,T-GIS)数据模型来描述、城市复杂道路网络的复杂特性.首先以复杂网络理论验证城市道路网络的复杂特性,其次从道路网络综合描述属性表达和网络数据逻辑关系3个方面构建城市复杂道路网络T-GIS数据模型.实践证明,本T-GIS模型具有很好的应用效果,很好表达道路网络空间信息及复杂逻辑关系,为道路拥堵和路径诱导及城市道路网络演化研究提供所需数据,且具有较好的推广价值.
文摘One of the most powerful functions of Geographic Information System for Transportation (GIS-T) is Dynamic Segmentation (DS), which is used to increase the efficiency and precision of road management by generating segments based on attributes. The road segments describing transportation data are both spatially and temporally referenced. For a variety of transportation applications, historical road segments must be preserved. This study presents an appropriate approach to preserve and retrieve the historical road segments efficiently. In the proposed method, only the portions of segments of a time stamp that have been changed into new segments rather than storing the entire segments for every old time stamp are recorded .The storage of these portions is based on the type of changes. A recursive algorithm is developed to retrieve all segments for every old time stamp. Experimental results using real data of Tehran City, Iran justify the strength of the proposed approach in many aspects. An important achievement of the results is that database volume for 2006, 2007 and 2008 within the Historical Line Event Table (HLET) is reduced by 70%, 80% and 78%, respectively. The proposed method has the potential to prevent from vast data redundancy and the unnecessary storage of entire segments for each time stamp. Since the present technique is performed on ordinary plain tables that are readable by all GIS software, special software platforms to manage the storage and retrieval of historical segments are not needed. In addition, this method simplifies spatio-temporal queries.
文摘Addressing transportation planning, operation and investment challenges requires increasingly sophisticated data and information management strategies. ITS (intelligent transportation systems) and CV (connected vehicle) technologies represent a new approach to capturing and using needed transportation data in real time or near real time. In the case of Michigan, several ITS programs have been launched successfully, but independently of each other. The objective of this research is to evaluate and assess all important factors that will influence the collection, management and use of ITS data, and recommend strategies to develop integrated, dynamic and adaptive data management systems for state transportation agencies.
基金Supported by the National Basic Research Program of China (No. 2006CB303000)the National Natural Science Foundation of China (No. 60773091, F020303).
文摘This paper studies a routing protocol used in the application of collecting real-time traffic information using mobile vehicles to monitor traffic status. The biggest challenge of vehicular ad hoe network routing protocol lies in the mismatch between the direction of moving vehicles and routed data. In order to deal with this mismatch, a mesh based routing protocol with a two-tier network architecture is proposed. By using mesh nodes deployed at intersections, data can be routed through an optimized path which can improve the delivery ratio and reduce the consumption of network resources. The simulation uses the mobility model processed from the GPS data of taxis mnning in Shanghai urban areas. The result shows that the proposed protocol outperforms the existing flooding protocol.
基金This work was supported in part by China National Natural Science Foundation under Grant 61271185,and the Fundamental Research Funds for the Central Universities
文摘WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System (ColTS). However, the mobility of nodes makes data dissemination a hard nut to crack. In this paper, we propose MSDD, a multiple mobile sinks data dissemination mechanism for solving the dissemination problem. The main ideas of MSDD are constructing a two-tier grid structure by a designated sink, exploiting a hierarchical monitoring mechanism, and employing a global agent to track the sink locations in order to make the emergencies reported to the sinks immediately, In addition, MSDD supports the query-driven data dissemination. Being compared with TTDD, MSDD is theoretically proved to have less communication overhead. We also validate MSDD outperforms TTDD in reliability and the emergency delivery latency bv simulations.
文摘This study explores the use of augmented reality smart glasses(ARSGs) by physicians and their adoption of these products in the Turkish medical industry.Google Glass was used as a demonstrative example for the introduction of ARSGs. We proposed an exploratory model based on the technology acceptance model by Davis. Exogenous factors in the model were defined by performing semi-structured in-depth interviews, along with the use of an expert panel in addition to the technology adoption literature. The framework was tested by means of a field study, data was collected via an Internet survey, and path analysis was used. The results indicate that there were a number of factors to be considered in order to understand ARSG adoption by physicians.Usefulness was influenced by ease of use, compatibility,ease of reminding, and speech recognition, while ease of use was affected by ease of learning, ease of medical education, external influence, and privacy. Privacy was the only negative factor that reduced the perceived ease of use,and was found to indirectly create a negative attitude.Compatibility emerged as the most significant external factor for usefulness. Developers of ARSGs should pay attention to healthcare-specific requirements for improved utilization and more extensive adoption of ARSGs in healthcare settings. In particular, they should focus on how to increase the compatibility of ARSGs. Further research needs to be conducted to explain the adoption intention of physicians.