In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):104...In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):1045-1049]and Monrad and Rootzén[Probab.Theory Related Fields,1995,101(2):173-192].展开更多
A relationship was discovered between the amplification factor and the number of load increments that are needed to limit the relative error to one percent in second-order elastic analyses with a predictor-corrector s...A relationship was discovered between the amplification factor and the number of load increments that are needed to limit the relative error to one percent in second-order elastic analyses with a predictor-corrector solution scheme.Previous research by the authors proposed a design equation to determine the required minimum number of load increments based on an evaluation of the elastic critical buckling load ratio.Further research has shown that an approximate amplification factor equation that is based on the B2 multiplier equation produces similar results when the amplification factor is less than approximately four.Eleven moment frames are used to verify the use of the new approximate amplification factor in the proposed design equation.展开更多
超高韧性水泥基材料(ultra high toughness cementitious composites,UHTCC)耐损伤能力强、裂缝控制能力好,具有超高的受压韧性及显著的受拉应变硬化特性。为提升钢框架结构的抗侧性能,分别将装配式RC、UHTCC抗侧力墙作为钢框架结构的...超高韧性水泥基材料(ultra high toughness cementitious composites,UHTCC)耐损伤能力强、裂缝控制能力好,具有超高的受压韧性及显著的受拉应变硬化特性。为提升钢框架结构的抗侧性能,分别将装配式RC、UHTCC抗侧力墙作为钢框架结构的抗侧力构件,进行足尺钢框架(STF)、钢框架-附加装配式RC抗侧力墙(SRCW)和钢框架-附加装配式UHTCC抗侧力墙(SHTCW)试件低周往复加载试验,对上述试件破坏模式、滞回性能、刚度、承载力、变形能力、应变及耗能性能等进行研究。试验表明,试件SHTCW、SRCW的峰值承载力相比于试件STF分别提高了25%和13%,抗侧力墙材料抗压强度值相近的情况下,试件SHTCW的峰值承载力较试件SRCW提高15%。相同加载位移角下,试件SHTCW的抗侧刚度及等效黏滞阻尼系数高于试件SRCW和STF,相比于RC抗侧力墙,UHTCC抗侧力墙具有更优异的抗侧性能及耗能能力,其与钢框架的变形协调能力更好。在试验研究基础上,采用OpenSees有限元程序,分别对STF、SRCW结构与SHTCW结构进行增量动力分析,相比于STF结构,SHTCW、SRCW结构各个性能水准的失效概率明显降低,倒塌储备系数分别提高了1.42和1.18倍,通过附加装配式UHTCC抗侧力墙,能够减轻地震荷载作用下钢框架结构的动力响应,有效提升钢框架结构抗震性能。展开更多
针对新能源可靠供电中的供需平衡问题,提出一种计及局部阴影工况的光储直流微电网能量管理。首先,针对光伏阵列在局部阴影等弱光照工况下,传统最大功率点跟踪方法在功率捕捉能力与能源利用效率方面的不足,利用蝠鲼优化算法(manta ray fo...针对新能源可靠供电中的供需平衡问题,提出一种计及局部阴影工况的光储直流微电网能量管理。首先,针对光伏阵列在局部阴影等弱光照工况下,传统最大功率点跟踪方法在功率捕捉能力与能源利用效率方面的不足,利用蝠鲼优化算法(manta ray foraging optimization,MRFO)的全局与局部搜索优势,提出一种结合MRFO的自适应电导增量法(manta ray foraging optimization-adaptive variable step-incremental conductance,MRFO-AVS-INC),以在特殊工况下实现对光伏出力的有效跟踪;其次,针对系统集成中存在的多源扰动问题,在储能系统的能量管理与控制方面,提出一种考虑蓄电池工作状态的改进下垂控制方法,通过引入蓄电池的荷电状态(state of charge,SOC)和健康状态(state of health,SOH)等参数,实现下垂系数的自适应调节,从而合理分配各蓄电池的输出功率;最后,在不同光照条件下对光储系统进行仿真验证。仿真结果表明,与基于粒子群算法的自适应变步长电导增量法(particle swarm optimization-adaptive variable stepincremental conductance,PSO-AVS-INC)及传统INC相比,MRFO-AVS-INC方法在收敛速度与跟踪稳定性方面表现更优;改进的自适应下垂控制有效实现了储能单元之间的状态均衡,延长了储能系统的整体使用寿命。展开更多
基金Supported by NSFC(Nos.11661025,12161024)Natural Science Foundation of Guangxi(Nos.2020GXNSFAA159118,2021GXNSFAA196045)+2 种基金Guangxi Science and Technology Project(No.Guike AD20297006)Training Program for 1000 Young and Middle-aged Cadre Teachers in Universities of GuangxiNational College Student's Innovation and Entrepreneurship Training Program(No.202110595049)。
文摘In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):1045-1049]and Monrad and Rootzén[Probab.Theory Related Fields,1995,101(2):173-192].
文摘A relationship was discovered between the amplification factor and the number of load increments that are needed to limit the relative error to one percent in second-order elastic analyses with a predictor-corrector solution scheme.Previous research by the authors proposed a design equation to determine the required minimum number of load increments based on an evaluation of the elastic critical buckling load ratio.Further research has shown that an approximate amplification factor equation that is based on the B2 multiplier equation produces similar results when the amplification factor is less than approximately four.Eleven moment frames are used to verify the use of the new approximate amplification factor in the proposed design equation.
文摘超高韧性水泥基材料(ultra high toughness cementitious composites,UHTCC)耐损伤能力强、裂缝控制能力好,具有超高的受压韧性及显著的受拉应变硬化特性。为提升钢框架结构的抗侧性能,分别将装配式RC、UHTCC抗侧力墙作为钢框架结构的抗侧力构件,进行足尺钢框架(STF)、钢框架-附加装配式RC抗侧力墙(SRCW)和钢框架-附加装配式UHTCC抗侧力墙(SHTCW)试件低周往复加载试验,对上述试件破坏模式、滞回性能、刚度、承载力、变形能力、应变及耗能性能等进行研究。试验表明,试件SHTCW、SRCW的峰值承载力相比于试件STF分别提高了25%和13%,抗侧力墙材料抗压强度值相近的情况下,试件SHTCW的峰值承载力较试件SRCW提高15%。相同加载位移角下,试件SHTCW的抗侧刚度及等效黏滞阻尼系数高于试件SRCW和STF,相比于RC抗侧力墙,UHTCC抗侧力墙具有更优异的抗侧性能及耗能能力,其与钢框架的变形协调能力更好。在试验研究基础上,采用OpenSees有限元程序,分别对STF、SRCW结构与SHTCW结构进行增量动力分析,相比于STF结构,SHTCW、SRCW结构各个性能水准的失效概率明显降低,倒塌储备系数分别提高了1.42和1.18倍,通过附加装配式UHTCC抗侧力墙,能够减轻地震荷载作用下钢框架结构的动力响应,有效提升钢框架结构抗震性能。
文摘针对新能源可靠供电中的供需平衡问题,提出一种计及局部阴影工况的光储直流微电网能量管理。首先,针对光伏阵列在局部阴影等弱光照工况下,传统最大功率点跟踪方法在功率捕捉能力与能源利用效率方面的不足,利用蝠鲼优化算法(manta ray foraging optimization,MRFO)的全局与局部搜索优势,提出一种结合MRFO的自适应电导增量法(manta ray foraging optimization-adaptive variable step-incremental conductance,MRFO-AVS-INC),以在特殊工况下实现对光伏出力的有效跟踪;其次,针对系统集成中存在的多源扰动问题,在储能系统的能量管理与控制方面,提出一种考虑蓄电池工作状态的改进下垂控制方法,通过引入蓄电池的荷电状态(state of charge,SOC)和健康状态(state of health,SOH)等参数,实现下垂系数的自适应调节,从而合理分配各蓄电池的输出功率;最后,在不同光照条件下对光储系统进行仿真验证。仿真结果表明,与基于粒子群算法的自适应变步长电导增量法(particle swarm optimization-adaptive variable stepincremental conductance,PSO-AVS-INC)及传统INC相比,MRFO-AVS-INC方法在收敛速度与跟踪稳定性方面表现更优;改进的自适应下垂控制有效实现了储能单元之间的状态均衡,延长了储能系统的整体使用寿命。
