In this paper, we study self-dual permutation codes over formal power series rings and finite principal ideal rings. We first give some results on the torsion codes associated with the linear codes over formal power s...In this paper, we study self-dual permutation codes over formal power series rings and finite principal ideal rings. We first give some results on the torsion codes associated with the linear codes over formal power series rings. These results allow for obtaining some conditions for non-existence of self-dual permutation codes over formal power series rings. Finally, we describe self-dual permutation codes over finite principal ideal rings by examining permutation codes over their component chain rings.展开更多
电力系统运行在非理想状态时,容易产生短暂的电压波动,此时并联有源电力滤波器(shunt active power filter,SAPF)采用无源控制策略无法高效、精确地调节电能质量,而常规滑模控制又容易引起抖振。针对上述情况,将无源控制和抗干扰能力更...电力系统运行在非理想状态时,容易产生短暂的电压波动,此时并联有源电力滤波器(shunt active power filter,SAPF)采用无源控制策略无法高效、精确地调节电能质量,而常规滑模控制又容易引起抖振。针对上述情况,将无源控制和抗干扰能力更强的超螺旋二阶滑模控制相结合,提出了一种无源超螺旋二阶滑模控制策略。首先,根据有源电力滤波器的数学模型建立基于正负序分离的欧拉−拉格朗日模型;其次,对系统的模型进行了无源性分析,且根据其无源性设计了无源控制器,同时采用超螺旋二阶滑模控制对无源控制器进一步优化,提高了系统整体的鲁棒性和抗干扰能力;最后,在理想状态和负载突变、负载不平衡、电网电压不平衡、单相电压突变4种非理想状态下,通过仿真实验验证了无源超螺旋二阶滑模控制策略的有效性和优越性。展开更多
In this paper hybrid converters with double inputs are investigated. Mainly any possible topologies are constructed and only one of them is chosen and modeled in none ideal format, by state space averaging method. Aft...In this paper hybrid converters with double inputs are investigated. Mainly any possible topologies are constructed and only one of them is chosen and modeled in none ideal format, by state space averaging method. After that small signal model and equilibrium point of that model is calculated. Finally with power sharing analysis the best point in efficiency was calculated.展开更多
当前,我国配电网中仍存在薄弱环节,运行风险较大。为保障配电网的安全可靠运行,提出了基于优劣解距离法(technique for order preference by similarity to ideal solution,TOPSIS)的典型性停电风险评估方法。首先,参考国家电网相关规程...当前,我国配电网中仍存在薄弱环节,运行风险较大。为保障配电网的安全可靠运行,提出了基于优劣解距离法(technique for order preference by similarity to ideal solution,TOPSIS)的典型性停电风险评估方法。首先,参考国家电网相关规程,定义了典型性停电事故。其次,通过汇总分析相关运行故障数据,归纳其事故典型性成因的主要影响因素,并应用TOPSIS分析法建立指标评价体系,分别从装备水平、运行维护水平和网架结构水平等方面对配电网典型性停电风险进行量化评估。最后,针对某停电区域进行实例验证,结合实地调研工作,发掘该区域配电网的典型问题,为配电网的建设与改造提供科学依据。展开更多
Let t be any positive integer and I(C_(n)) the edge ideal of a vertex-weighted oriented n-cycle graph C_(n).We provide explicit formulas for the regularity and depth of I(C_(n))^(t).In particular,we find that the regu...Let t be any positive integer and I(C_(n)) the edge ideal of a vertex-weighted oriented n-cycle graph C_(n).We provide explicit formulas for the regularity and depth of I(C_(n))^(t).In particular,we find that the regularity of I(C_(n))^(t)is a linear function;Ass(I(C_(n))^(t),the set of associated prime ideals of I(C_(n))^(t),equals Ass(I(C_(n))^(t);and the depth of I(C_(n))^(t)is a constant for all.We also give some examples to show that these results are related to the direction selection of edges and the weight of vertices.展开更多
文摘In this paper, we study self-dual permutation codes over formal power series rings and finite principal ideal rings. We first give some results on the torsion codes associated with the linear codes over formal power series rings. These results allow for obtaining some conditions for non-existence of self-dual permutation codes over formal power series rings. Finally, we describe self-dual permutation codes over finite principal ideal rings by examining permutation codes over their component chain rings.
文摘电力系统运行在非理想状态时,容易产生短暂的电压波动,此时并联有源电力滤波器(shunt active power filter,SAPF)采用无源控制策略无法高效、精确地调节电能质量,而常规滑模控制又容易引起抖振。针对上述情况,将无源控制和抗干扰能力更强的超螺旋二阶滑模控制相结合,提出了一种无源超螺旋二阶滑模控制策略。首先,根据有源电力滤波器的数学模型建立基于正负序分离的欧拉−拉格朗日模型;其次,对系统的模型进行了无源性分析,且根据其无源性设计了无源控制器,同时采用超螺旋二阶滑模控制对无源控制器进一步优化,提高了系统整体的鲁棒性和抗干扰能力;最后,在理想状态和负载突变、负载不平衡、电网电压不平衡、单相电压突变4种非理想状态下,通过仿真实验验证了无源超螺旋二阶滑模控制策略的有效性和优越性。
文摘In this paper hybrid converters with double inputs are investigated. Mainly any possible topologies are constructed and only one of them is chosen and modeled in none ideal format, by state space averaging method. After that small signal model and equilibrium point of that model is calculated. Finally with power sharing analysis the best point in efficiency was calculated.
文摘当前,我国配电网中仍存在薄弱环节,运行风险较大。为保障配电网的安全可靠运行,提出了基于优劣解距离法(technique for order preference by similarity to ideal solution,TOPSIS)的典型性停电风险评估方法。首先,参考国家电网相关规程,定义了典型性停电事故。其次,通过汇总分析相关运行故障数据,归纳其事故典型性成因的主要影响因素,并应用TOPSIS分析法建立指标评价体系,分别从装备水平、运行维护水平和网架结构水平等方面对配电网典型性停电风险进行量化评估。最后,针对某停电区域进行实例验证,结合实地调研工作,发掘该区域配电网的典型问题,为配电网的建设与改造提供科学依据。
基金This research is supported by the Natural Science Foundation of Jiangsu Province(BK20221353)the foundation of the Priority Academic Program Development of Jiangsu Higher Education Institutions.Finally,the authors would like to thank the referees who read the manuscript carefully and gave very helpful comments,which improved the paper both in mathematics and presentation.
文摘Let t be any positive integer and I(C_(n)) the edge ideal of a vertex-weighted oriented n-cycle graph C_(n).We provide explicit formulas for the regularity and depth of I(C_(n))^(t).In particular,we find that the regularity of I(C_(n))^(t)is a linear function;Ass(I(C_(n))^(t),the set of associated prime ideals of I(C_(n))^(t),equals Ass(I(C_(n))^(t);and the depth of I(C_(n))^(t)is a constant for all.We also give some examples to show that these results are related to the direction selection of edges and the weight of vertices.
