Too high energy consumption is widely recognized to be a critical problem in large-scale parallel computing systems.The LogP-based energy-saving model and the frequency scaling method were proposed to reduce energy co...Too high energy consumption is widely recognized to be a critical problem in large-scale parallel computing systems.The LogP-based energy-saving model and the frequency scaling method were proposed to reduce energy consumption analytically and systematically for other two representative barrier algorithms:tournament barrier and central counter barrier.Furthermore,energy optimization methods of these two barrier algorithms were implemented on parallel computing platform.The experimental results validate the effectiveness of the energy optimization methods.67.12% and 70.95% energy savings are obtained respectively for tournament barrier and central counter barrier on platforms with 2048 processes with 1.55%?8.80% performance loss.Furthermore,LogP-based energy-saving analytical model for these two barrier algorithms is highly accurate as the predicted energy savings are within 9.67% of the results obtained by simulation.展开更多
A thermo-economic model for the simulation and optimization of a CSHPSS (central solar heating plant with seasonal storage) is presented. The model, written in Matlab, allows to analyze the effects of different desi...A thermo-economic model for the simulation and optimization of a CSHPSS (central solar heating plant with seasonal storage) is presented. The model, written in Matlab, allows to analyze the effects of different design and operating variables on plant performance and cost. Daily and seasonal variations of solar irradiation at different latitudes are considered, and an original approximate model for thermal stratification is included. Since a limited computational time is required, the simulation model can be effectively integrated with a non-linear constrained optimization procedure so as to determine the optimal choice of design variables for different locations and operating conditions. The comparison between a two-variable and four-variable optimization for five different locations at various latitudes has been presented, showing a significant decrease in pay-back time with latitude. Finally a sensitivity analysis on the most important design and operating variables has been performed and presented. It emerges that the optimal insulator thickness always decreases with latitude. The optimal tilt angle is slightly lower than latitude only when the plant is designed to cover the whole thermal load, while higher tilt values are selected in case of partial load covering.展开更多
基金Projects(60903044,61170049) supported by National Natural Science Foundation of China
文摘Too high energy consumption is widely recognized to be a critical problem in large-scale parallel computing systems.The LogP-based energy-saving model and the frequency scaling method were proposed to reduce energy consumption analytically and systematically for other two representative barrier algorithms:tournament barrier and central counter barrier.Furthermore,energy optimization methods of these two barrier algorithms were implemented on parallel computing platform.The experimental results validate the effectiveness of the energy optimization methods.67.12% and 70.95% energy savings are obtained respectively for tournament barrier and central counter barrier on platforms with 2048 processes with 1.55%?8.80% performance loss.Furthermore,LogP-based energy-saving analytical model for these two barrier algorithms is highly accurate as the predicted energy savings are within 9.67% of the results obtained by simulation.
文摘A thermo-economic model for the simulation and optimization of a CSHPSS (central solar heating plant with seasonal storage) is presented. The model, written in Matlab, allows to analyze the effects of different design and operating variables on plant performance and cost. Daily and seasonal variations of solar irradiation at different latitudes are considered, and an original approximate model for thermal stratification is included. Since a limited computational time is required, the simulation model can be effectively integrated with a non-linear constrained optimization procedure so as to determine the optimal choice of design variables for different locations and operating conditions. The comparison between a two-variable and four-variable optimization for five different locations at various latitudes has been presented, showing a significant decrease in pay-back time with latitude. Finally a sensitivity analysis on the most important design and operating variables has been performed and presented. It emerges that the optimal insulator thickness always decreases with latitude. The optimal tilt angle is slightly lower than latitude only when the plant is designed to cover the whole thermal load, while higher tilt values are selected in case of partial load covering.