To reduce vehicle emissions in road networks, a new signal coordination algorithm based on approximate dynamic programming （ADP） is developed for two intersections. Taking the Jetta car as an experimental vehicle, f...To reduce vehicle emissions in road networks, a new signal coordination algorithm based on approximate dynamic programming （ADP） is developed for two intersections. Taking the Jetta car as an experimental vehicle, field tests are conducted in Changchun Street of Changchun city and vehicle emission factors in complete stop and uniform speed states are collected. Queue lengths and signal light colors of approach lanes are selected as state variables, and green switch plans are selected as decision variables of the system. Then the calculation model of the optimization index during the planning horizon is developed based on the basis function method of the ADP. The temporal-difference algorithm is employed to update the weighting factor vector of the approximate function. Simulations are conducted in Matlab and the results show that the established algorithm outperforms the conventional coordination algorithm in reducing vehicle emissions by 8.2%. Sensitive analysis of the planning horizon length on the evaluation index is also conducted and the statistical results show that the optimal length of the planning horizon is directly proportional to the traffic load.展开更多
With a water-supply network by dynamic programming. The minimal as an example, the network was optimized annual discounted costs were taken as an objective function and node pressure etc. as constraint conditions. The...With a water-supply network by dynamic programming. The minimal as an example, the network was optimized annual discounted costs were taken as an objective function and node pressure etc. as constraint conditions. The alternative pipe diameters were optimized as per enumeration method and the group allowing objective function with the least values would be the optimized one. It is proved the optimized pipe network reduced by 11.49% in terms of cost and the optimized ben- efits proved much significant.展开更多
The quest for energy efficiency has growing importance in high performance many-core systems. However, in current practices, the power slacks, which are the differences observed between the input power budget and the ...The quest for energy efficiency has growing importance in high performance many-core systems. However, in current practices, the power slacks, which are the differences observed between the input power budget and the actual power consumed in the many-core systems, are typically ignored, thus leading to poor energy efficiency. In this paper, we propose a scheme to effectively power the on-chip communications by exploiting the available power slack that is totally wasted in current many-core systems. As so, the demand for extra energy from external power sources （e.g., batteries） is minimized, which helps improve the overall energy efficiency. In essence, the power slack is stored at each node and the proposed routing algorithm uses a dynamic programming network to find the globally optimal path, along which the total energy stored on the nodes is the maximum. Experimental results have confirmed that the proposed scheme, with low hardware overhead, can reduce latency and extra energy consumption by 44% and 48%, respectively, compared with the two competing routing methods.展开更多
基金The National High Technology Research and Development Program of China (863 Program ) (No. 2011AA110304 )the National Natural Science Foundation of China (No. 50908100)
文摘To reduce vehicle emissions in road networks, a new signal coordination algorithm based on approximate dynamic programming （ADP） is developed for two intersections. Taking the Jetta car as an experimental vehicle, field tests are conducted in Changchun Street of Changchun city and vehicle emission factors in complete stop and uniform speed states are collected. Queue lengths and signal light colors of approach lanes are selected as state variables, and green switch plans are selected as decision variables of the system. Then the calculation model of the optimization index during the planning horizon is developed based on the basis function method of the ADP. The temporal-difference algorithm is employed to update the weighting factor vector of the approximate function. Simulations are conducted in Matlab and the results show that the established algorithm outperforms the conventional coordination algorithm in reducing vehicle emissions by 8.2%. Sensitive analysis of the planning horizon length on the evaluation index is also conducted and the statistical results show that the optimal length of the planning horizon is directly proportional to the traffic load.
文摘With a water-supply network by dynamic programming. The minimal as an example, the network was optimized annual discounted costs were taken as an objective function and node pressure etc. as constraint conditions. The alternative pipe diameters were optimized as per enumeration method and the group allowing objective function with the least values would be the optimized one. It is proved the optimized pipe network reduced by 11.49% in terms of cost and the optimized ben- efits proved much significant.
基金supported by the National Natural Science Foundation of China under Grant No.61376024 and No.61306024Natural Science Foundation of Guangdong Province under Grant No.S2013040014366Basic Research Program of Shenzhen under Grant No.JCYJ20140417113430642 and No.JCYJ 20140901003939020
文摘The quest for energy efficiency has growing importance in high performance many-core systems. However, in current practices, the power slacks, which are the differences observed between the input power budget and the actual power consumed in the many-core systems, are typically ignored, thus leading to poor energy efficiency. In this paper, we propose a scheme to effectively power the on-chip communications by exploiting the available power slack that is totally wasted in current many-core systems. As so, the demand for extra energy from external power sources （e.g., batteries） is minimized, which helps improve the overall energy efficiency. In essence, the power slack is stored at each node and the proposed routing algorithm uses a dynamic programming network to find the globally optimal path, along which the total energy stored on the nodes is the maximum. Experimental results have confirmed that the proposed scheme, with low hardware overhead, can reduce latency and extra energy consumption by 44% and 48%, respectively, compared with the two competing routing methods.
