This paper proposes a systematic method, integrating the uniform design (UD) of experiments and quantum-behaved particle swarm optimization (QPSO), to solve the problem of a robust design for a railway vehicle suspens...This paper proposes a systematic method, integrating the uniform design (UD) of experiments and quantum-behaved particle swarm optimization (QPSO), to solve the problem of a robust design for a railway vehicle suspension system. Based on the new nonlinear creep model derived from combining Hertz contact theory, Kalker's linear theory and a heuristic nonlinear creep model, the modeling and dynamic analysis of a 24 degree-of-freedom railway vehicle system were investigated. The Lyapunov indirect method was used to examine the effects of suspension parameters, wheel conicities and wheel rolling radii on critical hunting speeds. Generally, the critical hunting speeds of a vehicle system resulting from worn wheels with different wheel rolling radii are lower than those of a vehicle system having original wheels without different wheel rolling radii. Because of worn wheels, the critical hunting speed of a running railway vehicle substantially declines over the long term. For safety reasons, it is necessary to design the suspension system parameters to increase the robustness of the system and decrease the sensitive of wheel noises. By applying UD and QPSO, the nominal-the-best signal-to-noise ratio of the system was increased from -48.17 to -34.05 dB. The rate of improvement was 29.31%. This study has demonstrated that the integration of UD and QPSO can successfully reveal the optimal solution of suspension parameters for solving the robust design problem of a railway vehicle suspension system.展开更多
Mapping of three-dimensional network on chip is a key problem in the research of three-dimensional network on chip. The quality of the mapping algorithm used di- rectly affects the communication efficiency between IP ...Mapping of three-dimensional network on chip is a key problem in the research of three-dimensional network on chip. The quality of the mapping algorithm used di- rectly affects the communication efficiency between IP cores and plays an important role in the optimization of power consumption and throughput of the whole chip. In this paper, ba- sic concepts and related work of three-dimensional network on chip are introduced. Quantum-behaved particle swarm op- timization algorithm is applied to the mapping problem of three-dimensional network on chip for the first time. Sim- ulation results show that the mapping algorithm based on quantum-behaved particle swarm algorithm has faster con- vergence speed with much better optimization performance compared with the mapping algorithm based on particle swarm algorithm. It also can effectively reduce the power consumption of mapping of three-dimensional network on chip.展开更多
传统220 kV片区电网供电能力分析方法往往将电网分离出来单独计算,忽略了片区间110 k V高压配电网重构对潜在供电能力的挖掘作用,因此提出计及高压配电网转供能力的220 k V片区电网供电能力计算模型,在传统供电能力分析模型的基础上加...传统220 kV片区电网供电能力分析方法往往将电网分离出来单独计算,忽略了片区间110 k V高压配电网重构对潜在供电能力的挖掘作用,因此提出计及高压配电网转供能力的220 k V片区电网供电能力计算模型,在传统供电能力分析模型的基础上加入片区间高压配电网重构模型,利用网络重构来疏导220 k V片区电网间的潮流分布,挖掘潜在供电空间。其次构建适用于110 kV高压配电网负荷转供的重构模型,根据其拓扑特点抽象出变电单元及变电单元组的简化模型,筛选变电单元组拓扑状态,保留可行解,进而构建基于变电单元组可行状态选择的转供模型。以单元组可行拓扑状态选择变量代替传统开关0-1状态建模,有效降低问题求解维度,节约计算时间,适用于在线分析。以某城市220 k V片区电网算例进行仿真,结果表明计及高压配电网重构的多片区整体供电能力要高于单独计算每个区的供电能力总和,片区间通过高压配电网重构使得网络供电能力得到更充分的挖掘和利用,进一步提升资产利用率。展开更多
基金the Ministry of Science and Technology of Taiwan (Grants MOST 104-2221-E-327019, MOST 105-2221-E-327-014) for financial support of this study
文摘This paper proposes a systematic method, integrating the uniform design (UD) of experiments and quantum-behaved particle swarm optimization (QPSO), to solve the problem of a robust design for a railway vehicle suspension system. Based on the new nonlinear creep model derived from combining Hertz contact theory, Kalker's linear theory and a heuristic nonlinear creep model, the modeling and dynamic analysis of a 24 degree-of-freedom railway vehicle system were investigated. The Lyapunov indirect method was used to examine the effects of suspension parameters, wheel conicities and wheel rolling radii on critical hunting speeds. Generally, the critical hunting speeds of a vehicle system resulting from worn wheels with different wheel rolling radii are lower than those of a vehicle system having original wheels without different wheel rolling radii. Because of worn wheels, the critical hunting speed of a running railway vehicle substantially declines over the long term. For safety reasons, it is necessary to design the suspension system parameters to increase the robustness of the system and decrease the sensitive of wheel noises. By applying UD and QPSO, the nominal-the-best signal-to-noise ratio of the system was increased from -48.17 to -34.05 dB. The rate of improvement was 29.31%. This study has demonstrated that the integration of UD and QPSO can successfully reveal the optimal solution of suspension parameters for solving the robust design problem of a railway vehicle suspension system.
文摘Mapping of three-dimensional network on chip is a key problem in the research of three-dimensional network on chip. The quality of the mapping algorithm used di- rectly affects the communication efficiency between IP cores and plays an important role in the optimization of power consumption and throughput of the whole chip. In this paper, ba- sic concepts and related work of three-dimensional network on chip are introduced. Quantum-behaved particle swarm op- timization algorithm is applied to the mapping problem of three-dimensional network on chip for the first time. Sim- ulation results show that the mapping algorithm based on quantum-behaved particle swarm algorithm has faster con- vergence speed with much better optimization performance compared with the mapping algorithm based on particle swarm algorithm. It also can effectively reduce the power consumption of mapping of three-dimensional network on chip.
文摘传统220 kV片区电网供电能力分析方法往往将电网分离出来单独计算,忽略了片区间110 k V高压配电网重构对潜在供电能力的挖掘作用,因此提出计及高压配电网转供能力的220 k V片区电网供电能力计算模型,在传统供电能力分析模型的基础上加入片区间高压配电网重构模型,利用网络重构来疏导220 k V片区电网间的潮流分布,挖掘潜在供电空间。其次构建适用于110 kV高压配电网负荷转供的重构模型,根据其拓扑特点抽象出变电单元及变电单元组的简化模型,筛选变电单元组拓扑状态,保留可行解,进而构建基于变电单元组可行状态选择的转供模型。以单元组可行拓扑状态选择变量代替传统开关0-1状态建模,有效降低问题求解维度,节约计算时间,适用于在线分析。以某城市220 k V片区电网算例进行仿真,结果表明计及高压配电网重构的多片区整体供电能力要高于单独计算每个区的供电能力总和,片区间通过高压配电网重构使得网络供电能力得到更充分的挖掘和利用,进一步提升资产利用率。
