Road traffic crash data are useful tools to support the development, implementation, and assessment of highway safety programs that tend to reduce road traffic crashes. Collecting road traffic crash data aims at gaini...Road traffic crash data are useful tools to support the development, implementation, and assessment of highway safety programs that tend to reduce road traffic crashes. Collecting road traffic crash data aims at gaining a better understanding of road traffic operational problems, locating hazardous road sections, identifying risk factors, developing accurate diagnosis and remedial measures, and evaluating the effectiveness of road safety programs. Furthermore, they can be used by many agencies and businesses such as: law enforcements to identify persons at fault in road traffic crashes;insurers seeking facts about traffic crash claims;road safety researchers to access traffic crash reliable database;decision makers to develop long-term, statewide strategic plans for traffic and highway safety;and highway safety administrators to help educate the public. Given the practical importance of vehicle crash data, this paper presents an overview of the sources, trends and problems associated with road traffic crash data.展开更多
Convergence is the main trend for future network development. The multi-service bearer network,built upon the Internet Protocol/Multi-protocol Label Switching (IP/MPLS) technology,is a converged network with Quality o...Convergence is the main trend for future network development. The multi-service bearer network,built upon the Internet Protocol/Multi-protocol Label Switching (IP/MPLS) technology,is a converged network with Quality of Service (QoS) guarantee for business and enterprise customers. The integrated and unified service provisioning platform (including both service execution and development enviroments) can provide integrated audio,video and data services over multiple access networks. However,achieving network convergence and service convergence are long-term goals,which can only be realized step by step after comprehensive consideration of many factors like market demands,technologies,services and costs.展开更多
The Network Attachment Subsystem (NASS) is introduced to the Next Generation Network (NGN) architecture to enable services independent from access networks and support nomadism for fixed terminals. The NASS is respons...The Network Attachment Subsystem (NASS) is introduced to the Next Generation Network (NGN) architecture to enable services independent from access networks and support nomadism for fixed terminals. The NASS is responsible for managing the users attached to the access network in terms of user authentication, allocation of the IP address, and location management. In NGN R1, Telecommunications and Internet Converged Services and Protocols for Advanced Networking (TISPAN) studied the internal architecture and external interface protocols of NASS and published the relevant technical specifications. In NGN R2, TISPAN focuses on the study of mobility and nomadism as well as the ability to support various access network architectures. There still remain several issues that need further study.展开更多
文摘Road traffic crash data are useful tools to support the development, implementation, and assessment of highway safety programs that tend to reduce road traffic crashes. Collecting road traffic crash data aims at gaining a better understanding of road traffic operational problems, locating hazardous road sections, identifying risk factors, developing accurate diagnosis and remedial measures, and evaluating the effectiveness of road safety programs. Furthermore, they can be used by many agencies and businesses such as: law enforcements to identify persons at fault in road traffic crashes;insurers seeking facts about traffic crash claims;road safety researchers to access traffic crash reliable database;decision makers to develop long-term, statewide strategic plans for traffic and highway safety;and highway safety administrators to help educate the public. Given the practical importance of vehicle crash data, this paper presents an overview of the sources, trends and problems associated with road traffic crash data.
文摘Convergence is the main trend for future network development. The multi-service bearer network,built upon the Internet Protocol/Multi-protocol Label Switching (IP/MPLS) technology,is a converged network with Quality of Service (QoS) guarantee for business and enterprise customers. The integrated and unified service provisioning platform (including both service execution and development enviroments) can provide integrated audio,video and data services over multiple access networks. However,achieving network convergence and service convergence are long-term goals,which can only be realized step by step after comprehensive consideration of many factors like market demands,technologies,services and costs.
文摘The Network Attachment Subsystem (NASS) is introduced to the Next Generation Network (NGN) architecture to enable services independent from access networks and support nomadism for fixed terminals. The NASS is responsible for managing the users attached to the access network in terms of user authentication, allocation of the IP address, and location management. In NGN R1, Telecommunications and Internet Converged Services and Protocols for Advanced Networking (TISPAN) studied the internal architecture and external interface protocols of NASS and published the relevant technical specifications. In NGN R2, TISPAN focuses on the study of mobility and nomadism as well as the ability to support various access network architectures. There still remain several issues that need further study.