The benchmark test system for distribution systems is necessary and important for system analysis and result data checking.In order to meet the development demand of the distribution systems which integrate with a hig...The benchmark test system for distribution systems is necessary and important for system analysis and result data checking.In order to meet the development demand of the distribution systems which integrate with a high penetration of distributed generation(DG),a benchmark test system for the distribution systems which adapts to current and future development trends is proposed.Based on the concentric zone theory and the typical regional settlement model in China,three typical distribution system scenarios corresponding to different system circle structures and regional development characteristics are designed in this paper.In order to adapt to the trend that the distribution systems will present the mixed state of AC and DC,a typical improvement scheme of distribution systems in urban scenario is presented.The benchmark test system of low-voltage distribution systems in a rural scenario is also designed because of the high penetration of DG.Moreover,the system structure,load parameters,integrated capacity and output characteristics of varies types of DG in different scenarios are described in detail.Finally,the simulation results,such as the time series power flow,reliability evaluation and hosting capacity of DGs are given.The benchmark test system proposed in this paper will lay a foundation for future research on distribution systems with a high proportion of DG and effectively support the distribution systems planning,design,operations and dispatches.展开更多
针对传统灰狼优化算法位置更新时勘探与开发失衡,收敛速度慢且陷入局部最优的问题,提出一种改进的灰狼算法(balanced grey wolf algorithm based on fitness back learning,BGWO),引入非线性控制参数,增强算法前期勘探能力,加速收敛;在...针对传统灰狼优化算法位置更新时勘探与开发失衡,收敛速度慢且陷入局部最优的问题,提出一种改进的灰狼算法(balanced grey wolf algorithm based on fitness back learning,BGWO),引入非线性控制参数,增强算法前期勘探能力,加速收敛;在种群迭代阶段采用重心反向学习的最优适应度权重更新策略,平衡算法的勘探与开发。16组基准函数测试结果表明,改进后算法能自适应跳出局部最优,在加快算法收敛速度的同时提高全局收敛能力与精度。将BGWO应用于PV型旋风分离器粒级效率GBDT(gradient boosting decision tree)的建模,提高了GBDT的精度,模型相关系数0.980,均方误差0.00079,BGWO-GBDT与GBDT、PSO-GBDT和GWO-GBDT相对比,建模精度和稳定性明显提高,验证了BGWO的有效性。展开更多
Itanium is the first generation product processor based on IA-64 architecture. ORC(Open Research Compil-er )provides an open source IPF(Itanium Processor Family)research compiler infrastructure. We have compiled andru...Itanium is the first generation product processor based on IA-64 architecture. ORC(Open Research Compil-er )provides an open source IPF(Itanium Processor Family)research compiler infrastructure. We have compiled andrun NAS Benchmarks on the Itanium machine. This paper briefly describes the performance of orcc, sgicc and gcc inthe following 3 ways: execution time, compilation time, and executable file size. The results show that orcc has near-ly the same performance as sgicc, which is 2 fold faster over gcc in the aspect of execution time. We also find that evenwith the best-optimized program, the utilization ratio of process resources is no more that 70%.展开更多
基金supported in part by the National Key Research and Development Program of China under Grant 2016YFB0900100in part by the National Natural Science Foundation of China under Grant 51977140,Grant U1866207in part by the Natural Science Foundation of Tianjin under Grant 19JCYBJC21300.
文摘The benchmark test system for distribution systems is necessary and important for system analysis and result data checking.In order to meet the development demand of the distribution systems which integrate with a high penetration of distributed generation(DG),a benchmark test system for the distribution systems which adapts to current and future development trends is proposed.Based on the concentric zone theory and the typical regional settlement model in China,three typical distribution system scenarios corresponding to different system circle structures and regional development characteristics are designed in this paper.In order to adapt to the trend that the distribution systems will present the mixed state of AC and DC,a typical improvement scheme of distribution systems in urban scenario is presented.The benchmark test system of low-voltage distribution systems in a rural scenario is also designed because of the high penetration of DG.Moreover,the system structure,load parameters,integrated capacity and output characteristics of varies types of DG in different scenarios are described in detail.Finally,the simulation results,such as the time series power flow,reliability evaluation and hosting capacity of DGs are given.The benchmark test system proposed in this paper will lay a foundation for future research on distribution systems with a high proportion of DG and effectively support the distribution systems planning,design,operations and dispatches.
文摘针对传统灰狼优化算法位置更新时勘探与开发失衡,收敛速度慢且陷入局部最优的问题,提出一种改进的灰狼算法(balanced grey wolf algorithm based on fitness back learning,BGWO),引入非线性控制参数,增强算法前期勘探能力,加速收敛;在种群迭代阶段采用重心反向学习的最优适应度权重更新策略,平衡算法的勘探与开发。16组基准函数测试结果表明,改进后算法能自适应跳出局部最优,在加快算法收敛速度的同时提高全局收敛能力与精度。将BGWO应用于PV型旋风分离器粒级效率GBDT(gradient boosting decision tree)的建模,提高了GBDT的精度,模型相关系数0.980,均方误差0.00079,BGWO-GBDT与GBDT、PSO-GBDT和GWO-GBDT相对比,建模精度和稳定性明显提高,验证了BGWO的有效性。
文摘Itanium is the first generation product processor based on IA-64 architecture. ORC(Open Research Compil-er )provides an open source IPF(Itanium Processor Family)research compiler infrastructure. We have compiled andrun NAS Benchmarks on the Itanium machine. This paper briefly describes the performance of orcc, sgicc and gcc inthe following 3 ways: execution time, compilation time, and executable file size. The results show that orcc has near-ly the same performance as sgicc, which is 2 fold faster over gcc in the aspect of execution time. We also find that evenwith the best-optimized program, the utilization ratio of process resources is no more that 70%.