The availability of computers and communication networks allows us to gather and analyse data on a far larger scale than previously. At present, it is believed that statistics is a suitable method to analyse networks ...The availability of computers and communication networks allows us to gather and analyse data on a far larger scale than previously. At present, it is believed that statistics is a suitable method to analyse networks with millions, or more, of vertices. The MATLAB language, with its mass of statistical functions, is a good choice to rapidly realize an algorithm prototype of complex networks. The performance of the MATLAB codes can be further improved by using graphic processor units （GPU）. This paper presents the strategies and performance of the GPU implementation of a complex networks package, and the Jacket toolbox of MATLAB is used. Compared with some commercially available CPU implementations, GPU can achieve a speedup of, on average, 11.3x. The experimental result proves that the GPU platform combined with the MATLAB language is a good combination for complex network research.展开更多
Based on the three-dimensional particle-in-cell （PIC） method and Compute Unified Device Architecture （CUDA）, a parallel particle simulation code combined with a graphic processor unit （GPU） has been developed fo...Based on the three-dimensional particle-in-cell （PIC） method and Compute Unified Device Architecture （CUDA）, a parallel particle simulation code combined with a graphic processor unit （GPU） has been developed for the simulation of charge-exchange （CEX） xenon ions in the plume of an ion thruster. Using the proposed technique, the potential and CEX plasma distribution are calculated for the ion thruster plume surrounding the DS1 spacecraft at different thrust levels. The simulation results are in good agreement with measured CEX ion parameters reported in literature, and the CPU＇s results are equal to a CPU＇s. Compared with a single CPU Intel Core 2 E6300, 16-processor GPU NVIDIA GeForce 9400 GT indicates a speedup factor of 3.6 when the total macro particle number is 1.1 × 10^6. The simulation results also reveal how the back flow CEX plasma affects the spacecraft floating potential, which indicates that the plume of the ion thruster is indeed able to alleviate the extreme negative floating potentials of spacecraft in geosynchronous orbit.展开更多
Graphics processors have received an increasing attention with the growing demand for gaming,video streaming,and many other applications.During the graphics rendering with OpenGL,host CPU needs the runtime attributes ...Graphics processors have received an increasing attention with the growing demand for gaming,video streaming,and many other applications.During the graphics rendering with OpenGL,host CPU needs the runtime attributes to move on to the next procedure of rendering,which covers almost all the function units of graphics pipeline.Current methods suffer from the memory capacity issues to hold the variables or huge amount of data parsing paths which can cause congestion on the interface between graphics processor and host CPU.This paper refers to the operation principle of commuting bus,and proposes a bus-like data feedback mechanism(BFM)to traverse all the pipeline stages and collect the run-time status data or execution error of graphics rendering,then send them back to the host CPU.BFM can work in parallel with the graphics rendering logic.This method can complete the data feedback ta.sk easily with only 0.6%increase of resource utilization and has no negative impact on performance,which also obtains 1.3 times speed enhancement compared with a traditional approach.展开更多
基金Project supported by the Science Fund for Creative Research Groups of the National Natural Science Foundation of China (Grant No.60921062)the National Natural Science Foundation of China (Grant No.60873014)the Young Scientists Fund of the National Natural Science Foundation of China (Grant Nos.61003082 and 60903059)
文摘The availability of computers and communication networks allows us to gather and analyse data on a far larger scale than previously. At present, it is believed that statistics is a suitable method to analyse networks with millions, or more, of vertices. The MATLAB language, with its mass of statistical functions, is a good choice to rapidly realize an algorithm prototype of complex networks. The performance of the MATLAB codes can be further improved by using graphic processor units （GPU）. This paper presents the strategies and performance of the GPU implementation of a complex networks package, and the Jacket toolbox of MATLAB is used. Compared with some commercially available CPU implementations, GPU can achieve a speedup of, on average, 11.3x. The experimental result proves that the GPU platform combined with the MATLAB language is a good combination for complex network research.
基金supported by National Natural Science Foundation of China (No. 10805004)Foundation of National Key Lab. of Science and Technology on Vacuum & Cryogenic of China (No. 9140C550404100C55)
文摘Based on the three-dimensional particle-in-cell （PIC） method and Compute Unified Device Architecture （CUDA）, a parallel particle simulation code combined with a graphic processor unit （GPU） has been developed for the simulation of charge-exchange （CEX） xenon ions in the plume of an ion thruster. Using the proposed technique, the potential and CEX plasma distribution are calculated for the ion thruster plume surrounding the DS1 spacecraft at different thrust levels. The simulation results are in good agreement with measured CEX ion parameters reported in literature, and the CPU＇s results are equal to a CPU＇s. Compared with a single CPU Intel Core 2 E6300, 16-processor GPU NVIDIA GeForce 9400 GT indicates a speedup factor of 3.6 when the total macro particle number is 1.1 × 10^6. The simulation results also reveal how the back flow CEX plasma affects the spacecraft floating potential, which indicates that the plume of the ion thruster is indeed able to alleviate the extreme negative floating potentials of spacecraft in geosynchronous orbit.
基金the National Natural Science Foundation of China(Nos.61834005,61772417,61602377,61802304 and 61874087)the International Science and Technology Cooperation Program of Shaanxi China(No.2018KW-006)。
文摘Graphics processors have received an increasing attention with the growing demand for gaming,video streaming,and many other applications.During the graphics rendering with OpenGL,host CPU needs the runtime attributes to move on to the next procedure of rendering,which covers almost all the function units of graphics pipeline.Current methods suffer from the memory capacity issues to hold the variables or huge amount of data parsing paths which can cause congestion on the interface between graphics processor and host CPU.This paper refers to the operation principle of commuting bus,and proposes a bus-like data feedback mechanism(BFM)to traverse all the pipeline stages and collect the run-time status data or execution error of graphics rendering,then send them back to the host CPU.BFM can work in parallel with the graphics rendering logic.This method can complete the data feedback ta.sk easily with only 0.6%increase of resource utilization and has no negative impact on performance,which also obtains 1.3 times speed enhancement compared with a traditional approach.
