In this paper, we considered the equality problem of weighted Bajraktarević means with weighted quasi-arithmetic means. Using the method of substituting for functions, we first transform the equality problem into solv...In this paper, we considered the equality problem of weighted Bajraktarević means with weighted quasi-arithmetic means. Using the method of substituting for functions, we first transform the equality problem into solving an equivalent functional equation. We obtain the necessary and sufficient conditions for the equality equation.展开更多
The exponential Randić index has important applications in the fields of biology and chemistry. The exponential Randić index of a graph G is defined as the sum of the weights e 1 d( u )d( v ) of all edges uv of G, whe...The exponential Randić index has important applications in the fields of biology and chemistry. The exponential Randić index of a graph G is defined as the sum of the weights e 1 d( u )d( v ) of all edges uv of G, where d( u ) denotes the degree of a vertex u in G. The paper mainly provides the upper and lower bounds of the exponential Randić index in quasi-tree graphs, and characterizes the extremal graphs when the bounds are achieved.展开更多
In this article, we propose by using the Hausdorff distance Simpson’s rule for the triple integral of a fuzzy-valued function and the error bound of this method, one of the variables of which is fuzzy. In addition, t...In this article, we propose by using the Hausdorff distance Simpson’s rule for the triple integral of a fuzzy-valued function and the error bound of this method, one of the variables of which is fuzzy. In addition, thin δ-fine partitions are introduced. The integration domain is a quasi-fuzzy parallelipiped. A numerical example is presented in order to show the application and the significance of the method.展开更多
The higher-order numerical scheme of nonlinear advection-diffusion equations is studied in this article, where the space fractional derivatives are evaluated by using weighted and shifted Grünwald difference oper...The higher-order numerical scheme of nonlinear advection-diffusion equations is studied in this article, where the space fractional derivatives are evaluated by using weighted and shifted Grünwald difference operators and combining the compact technique, in the time direction is discretized by the Crank-Nicolson method. Through the energy method, the stability and convergence of the numerical scheme in the sense of L<sub>2</sub>-norm are proved, and the convergence order is . Some examples are given to show that our numerical scheme is effective.展开更多
准比例谐振(quasi-proportion resonant,Quasi-PR)控制器可克服传统比例谐振(proportion resonant,PR)控制器带宽窄、抗频率偏移能力差的缺点,基于此提出了基于三单相Quasi-PR控制的中点箝位式(neutral point clamped,NPC)三电平光伏并...准比例谐振(quasi-proportion resonant,Quasi-PR)控制器可克服传统比例谐振(proportion resonant,PR)控制器带宽窄、抗频率偏移能力差的缺点,基于此提出了基于三单相Quasi-PR控制的中点箝位式(neutral point clamped,NPC)三电平光伏并网逆变器控制策略。Quasi-PR控制器继承了传统PR控制器的优点,避免了矢量控制策略中复杂的坐标变换、解耦控制和前馈补偿等,简化了控制算法。同时当电网频率发生偏移时,Quasi-PR控制器仍能实现对交流电流的无静差跟踪。此外,为减少电网不平衡时产生的较大谐波电流含量,设计了基于Quasi-PR控制的分次谐波补偿器。仿真结果表明了所提控制策略的有效性。展开更多
针对Quasi-UDG模型下无线传感器网络随机部署的拓扑特征,提出了一种非测距基于权重的定位算法EWLS(Enhanced Weighted Least Square).首先,设计出一种节点跳数和距离关系估计的方法,然后依据跳数值与距离关系的概率表达式,给出EWLS定位...针对Quasi-UDG模型下无线传感器网络随机部署的拓扑特征,提出了一种非测距基于权重的定位算法EWLS(Enhanced Weighted Least Square).首先,设计出一种节点跳数和距离关系估计的方法,然后依据跳数值与距离关系的概率表达式,给出EWLS定位算法中节点测量距离信息的权重.仿真实验表明,在不同的锚节点密度、Quasi-UDG模型因子和平均邻居节点数的参数下,EWLS算法定位误差较小,同最小均方误差相比,有效地提高了节点定位的精度.展开更多
文摘In this paper, we considered the equality problem of weighted Bajraktarević means with weighted quasi-arithmetic means. Using the method of substituting for functions, we first transform the equality problem into solving an equivalent functional equation. We obtain the necessary and sufficient conditions for the equality equation.
文摘The exponential Randić index has important applications in the fields of biology and chemistry. The exponential Randić index of a graph G is defined as the sum of the weights e 1 d( u )d( v ) of all edges uv of G, where d( u ) denotes the degree of a vertex u in G. The paper mainly provides the upper and lower bounds of the exponential Randić index in quasi-tree graphs, and characterizes the extremal graphs when the bounds are achieved.
文摘In this article, we propose by using the Hausdorff distance Simpson’s rule for the triple integral of a fuzzy-valued function and the error bound of this method, one of the variables of which is fuzzy. In addition, thin δ-fine partitions are introduced. The integration domain is a quasi-fuzzy parallelipiped. A numerical example is presented in order to show the application and the significance of the method.
文摘The higher-order numerical scheme of nonlinear advection-diffusion equations is studied in this article, where the space fractional derivatives are evaluated by using weighted and shifted Grünwald difference operators and combining the compact technique, in the time direction is discretized by the Crank-Nicolson method. Through the energy method, the stability and convergence of the numerical scheme in the sense of L<sub>2</sub>-norm are proved, and the convergence order is . Some examples are given to show that our numerical scheme is effective.
文摘准比例谐振(quasi-proportion resonant,Quasi-PR)控制器可克服传统比例谐振(proportion resonant,PR)控制器带宽窄、抗频率偏移能力差的缺点,基于此提出了基于三单相Quasi-PR控制的中点箝位式(neutral point clamped,NPC)三电平光伏并网逆变器控制策略。Quasi-PR控制器继承了传统PR控制器的优点,避免了矢量控制策略中复杂的坐标变换、解耦控制和前馈补偿等,简化了控制算法。同时当电网频率发生偏移时,Quasi-PR控制器仍能实现对交流电流的无静差跟踪。此外,为减少电网不平衡时产生的较大谐波电流含量,设计了基于Quasi-PR控制的分次谐波补偿器。仿真结果表明了所提控制策略的有效性。
文摘针对Quasi-UDG模型下无线传感器网络随机部署的拓扑特征,提出了一种非测距基于权重的定位算法EWLS(Enhanced Weighted Least Square).首先,设计出一种节点跳数和距离关系估计的方法,然后依据跳数值与距离关系的概率表达式,给出EWLS定位算法中节点测量距离信息的权重.仿真实验表明,在不同的锚节点密度、Quasi-UDG模型因子和平均邻居节点数的参数下,EWLS算法定位误差较小,同最小均方误差相比,有效地提高了节点定位的精度.
