Transmission Control Protocol （TCP） in infrastructure based vehicular net- works is dedicated to support reliable Intemet services for mobile users. However, an end-to- end TCP flow not only experiences some com- mo...Transmission Control Protocol （TCP） in infrastructure based vehicular net- works is dedicated to support reliable Intemet services for mobile users. However, an end-to- end TCP flow not only experiences some com- mon challenges in wireless mobile networks, such as high packet loss rate, medium access competition, unstable wireless bandwidth, and dynamic topology, etc., but also suffers from performance degradation due to traffic congestion at the Road-Side Units （RSUs） that connect the wireline and wireless networks. In order to address the challenging issues related to reliable TCP transmissions in infrastruc- ture based vehicular networks, we propose an RSU based TCP （R-TCP） scheme. For wireline source nodes, R-TCP adopts a novel flow control mechanism to adjust transmission rates according to the status of bottleneck link. Specifically, during the short wireless connec- tion time in Infrastructure based vehicular net- works, R-TCP quickly chooses an ideal trans- mission rate for data transmissions instead of activating the slow start algorithm after the connection is established, and successfully avoids the oscillation of the transmission rate. Simulation results show that R-TCP achieves great advantages than some relate proposals in terms of throughput, end-to-end delay, and packet loss rate.展开更多
The growth and evolution of the knowledge network in supply chain can be characterized by dynamic growth clustering and non-homogeneous degree distribution.The networks with the above characteristics are also known as...The growth and evolution of the knowledge network in supply chain can be characterized by dynamic growth clustering and non-homogeneous degree distribution.The networks with the above characteristics are also known as scale-free networks.In this paper,the knowledge network model in supply chain is established,in which the preferential attachment mechanism based on the node strength is adopted to simulate the growth and evolution of the network.The nodes in the network have a certain preference in the choice of a knowledge partner.On the basis of the network model,the robustness of the three network models based on different preferential attachment strategies is investigated.The robustness is also referred to as tolerances when the nodes are subjected to random destruction and malicious damage.The simulation results of this study show that the improved network has higher connectivity and stability.展开更多
The purpose of this article was to analyse how fisheries governance can be improved when there is low enforcement capacity by state＇s institutions. Based on the theoretical arguments from the neo-institutionalism and...The purpose of this article was to analyse how fisheries governance can be improved when there is low enforcement capacity by state＇s institutions. Based on the theoretical arguments from the neo-institutionalism and the social capital approaches, the findings of this research point to the role of fishing cooperatives＇ structural organization on the attitude of individuals to comply with regulations. Using a most similar comparative method, it was found that fishers with higher scores of compliance belong to cooperatives that have an outstanding leader, control mechanisms, as well as multi-actor external networks which connect the organization with other networks and thus facilitate the access to knowledge, technology and activities related to conservation and sustainable fishing. The findings of the research coincide with other studies about the importance of leadership that enable good fishing management. This may help in the design of different strategies to address situations with low state capacity to ensure compliance and contribute to solve problems of commons, such as the one in marine fisheries.展开更多
基金supported in part by Fundamental Research Funds for the Central Universities of China under Grant(N140405004) partly by National Natural Science Foundation of China(61373159)+1 种基金partly by Educational Committee of Liaoning Province science and technology research projects under Grant (L2013096)partly by Key Laboratory Project Funds of Shenyang Ligong University (4771004kfs03)
文摘Transmission Control Protocol （TCP） in infrastructure based vehicular net- works is dedicated to support reliable Intemet services for mobile users. However, an end-to- end TCP flow not only experiences some com- mon challenges in wireless mobile networks, such as high packet loss rate, medium access competition, unstable wireless bandwidth, and dynamic topology, etc., but also suffers from performance degradation due to traffic congestion at the Road-Side Units （RSUs） that connect the wireline and wireless networks. In order to address the challenging issues related to reliable TCP transmissions in infrastruc- ture based vehicular networks, we propose an RSU based TCP （R-TCP） scheme. For wireline source nodes, R-TCP adopts a novel flow control mechanism to adjust transmission rates according to the status of bottleneck link. Specifically, during the short wireless connec- tion time in Infrastructure based vehicular net- works, R-TCP quickly chooses an ideal trans- mission rate for data transmissions instead of activating the slow start algorithm after the connection is established, and successfully avoids the oscillation of the transmission rate. Simulation results show that R-TCP achieves great advantages than some relate proposals in terms of throughput, end-to-end delay, and packet loss rate.
基金Supported by the National Natural Science Foundation of China(No.71172169)
文摘The growth and evolution of the knowledge network in supply chain can be characterized by dynamic growth clustering and non-homogeneous degree distribution.The networks with the above characteristics are also known as scale-free networks.In this paper,the knowledge network model in supply chain is established,in which the preferential attachment mechanism based on the node strength is adopted to simulate the growth and evolution of the network.The nodes in the network have a certain preference in the choice of a knowledge partner.On the basis of the network model,the robustness of the three network models based on different preferential attachment strategies is investigated.The robustness is also referred to as tolerances when the nodes are subjected to random destruction and malicious damage.The simulation results of this study show that the improved network has higher connectivity and stability.
文摘The purpose of this article was to analyse how fisheries governance can be improved when there is low enforcement capacity by state＇s institutions. Based on the theoretical arguments from the neo-institutionalism and the social capital approaches, the findings of this research point to the role of fishing cooperatives＇ structural organization on the attitude of individuals to comply with regulations. Using a most similar comparative method, it was found that fishers with higher scores of compliance belong to cooperatives that have an outstanding leader, control mechanisms, as well as multi-actor external networks which connect the organization with other networks and thus facilitate the access to knowledge, technology and activities related to conservation and sustainable fishing. The findings of the research coincide with other studies about the importance of leadership that enable good fishing management. This may help in the design of different strategies to address situations with low state capacity to ensure compliance and contribute to solve problems of commons, such as the one in marine fisheries.
