Developing parallel applications on heterogeneous processors is facing the challenges of 'memory wall',due to limited capacity of local storage,limited bandwidth and long latency for memory access. Aiming at t...Developing parallel applications on heterogeneous processors is facing the challenges of 'memory wall',due to limited capacity of local storage,limited bandwidth and long latency for memory access. Aiming at this problem,a parallelization approach was proposed with six memory optimization schemes for CG,four schemes of them aiming at all kinds of sparse matrix-vector multiplication (SPMV) operation. Conducted on IBM QS20,the parallelization approach can reach up to 21 and 133 times speedups with size A and B,respectively,compared with single power processor element. Finally,the conclusion is drawn that the peak bandwidth of memory access on Cell BE can be obtained in SPMV,simple computation is more efficient on heterogeneous processors and loop-unrolling can hide local storage access latency while executing scalar operation on SIMD cores.展开更多
Desertification control is a crucial way to enhancing the ecological conditions of arid and semi-arid regions, and maintaining sustainable development globally. Designing and improving an ecological compensation mecha...Desertification control is a crucial way to enhancing the ecological conditions of arid and semi-arid regions, and maintaining sustainable development globally. Designing and improving an ecological compensation mechanism for desertification control has great significance related to achieving balance amongst the needs of different economic subjects and the assurance of a sustained and stable supply of desert ecosystem services. In this paper,(1) the theoretical bases of ecological compensation for desertification control were re-analyzed;(2) the research status and challenges of three important topics related to ecological compensation for desertification control were systemically discussed, including compensation standards, ecosystem service supply-consumption process and multi-scale effects, and resource-environment basis and policy orientation;(3) a research framework of ecological compensation for desertification control based on the process of desert ecosystem service supply–flow–consumption was proposed;(4) and finally, seven priority research issues were discussed, which aimed to support ecological compensation policy-making and ecological engineering implementation for desertification control.展开更多
基金Project(2008AA01A201) supported the National High-tech Research and Development Program of ChinaProjects(60833004, 60633050) supported by the National Natural Science Foundation of China
文摘Developing parallel applications on heterogeneous processors is facing the challenges of 'memory wall',due to limited capacity of local storage,limited bandwidth and long latency for memory access. Aiming at this problem,a parallelization approach was proposed with six memory optimization schemes for CG,four schemes of them aiming at all kinds of sparse matrix-vector multiplication (SPMV) operation. Conducted on IBM QS20,the parallelization approach can reach up to 21 and 133 times speedups with size A and B,respectively,compared with single power processor element. Finally,the conclusion is drawn that the peak bandwidth of memory access on Cell BE can be obtained in SPMV,simple computation is more efficient on heterogeneous processors and loop-unrolling can hide local storage access latency while executing scalar operation on SIMD cores.
基金National Natural Science Foundation of China,No.71573245National Key Research and Development Program of China,No.2016YFC0501002
文摘Desertification control is a crucial way to enhancing the ecological conditions of arid and semi-arid regions, and maintaining sustainable development globally. Designing and improving an ecological compensation mechanism for desertification control has great significance related to achieving balance amongst the needs of different economic subjects and the assurance of a sustained and stable supply of desert ecosystem services. In this paper,(1) the theoretical bases of ecological compensation for desertification control were re-analyzed;(2) the research status and challenges of three important topics related to ecological compensation for desertification control were systemically discussed, including compensation standards, ecosystem service supply-consumption process and multi-scale effects, and resource-environment basis and policy orientation;(3) a research framework of ecological compensation for desertification control based on the process of desert ecosystem service supply–flow–consumption was proposed;(4) and finally, seven priority research issues were discussed, which aimed to support ecological compensation policy-making and ecological engineering implementation for desertification control.
