基于可信性测度的模糊线性不等式组的确定性等价

在模糊优化决策问题中,约束条件包含模糊线性不等式组.如何把它们转化为确定性的等价形式,这在模糊控制和模糊决策中起着重要的作用.可信性测度是模糊数学实现公理化体系的一个基础.本文在可信性测度的基础上,探讨了模糊约束在一定的满意度水平之下转化为确定性的等价式,同时就三角形模糊变量给出了模糊线性不等式组的确定性等价的具体表达式.     

A theoretical analysis of the dynamic response of metallic sandwich beam under impulsive loading

The objective of this paper is to analytically study the dynamic response of a fully clamped metallic sandwich beam under impulsive loading. The membrane factor method is employed to derive the solutions for large deflections and time responses of the sandwich beam, in which the interaction of bending and stretching is considered. Moreover, tighter ‘bounds’ of the solutions are obtained. It is shown that the present solutions are in good agreements with the previous finite element results and lie in the bounds of the solutions. It is clear that core strength and membrane force induced by large deflections have significant effects on the dynamic response of sandwich beam with increasing the transient deflections. The present method is efficient and simple for the dynamic response analysis of large deflections of metallic sandwich structures.     

Natural convection heat transfer characteristics of TiO2–H2O nanofluids in a cavity filled with metal foam

Journal of Thermal Analysis and Calorimetry - In this paper, TiO2–H2O nanofluids are used instead of traditional mediums such as water and oil as the heat transfer medium. For the purpose of...     

点缺陷对表面生长动力学标度行为的影响

基于含噪声Kuramoto-Sivashinsky方程, 采用动力学重正化群技术, 研究生长表面存在点缺陷或杂质对表面生长动力学标度行为的影响, 得到了相应的粗糙度指数α 和动力学标度指数z. 所得结果表明, 点缺陷的存在使生长表面粗化, 并缩短达到稳定生长的弛豫时间.     

Bijective maps preserving commutators on a solvable classical group

Let F be a field, T n the group consisting of all n × n invertible upper triangular matrices over F . In this article we classify bijective maps φ from T n to itself satisfying φ[x, y] = [φ(x), φ(y)]. We show that each such map differs only slightly from an automorphism of T n .     

增益图与其底图的正惯性指数之间的关系

设$\mathbb{T}$是模为1的复数乘法子群.图$G=(V,E)$,这里$V,E$分别表示图的点和边.增益图是将底图中的每条边赋于$\mathbb{T}$中的某个数值$\varphi(v_iv_j)$,且满足$\varphi(v_iv_j) =\overline{\varphi(v_jv_i)}$.将赋值以后的增益图表示为$(G,\varphi)$.设$i_+(G,\varphi)$和$i_+(G)$分别表示增益图与底图的正惯性指数,本文证明了如下结论: $$ - c( G ) \le {i_ + } ( {G,\varphi } ) - {i_ + }( G ) \le c( G ), $$ 这里$c(G)$表示圈空间维数,并且刻画了等号成立时候的所有极图.     

Natural convection of composite nanofluids based on a two-phase lattice Boltzmann model

Journal of Thermal Analysis and Calorimetry - A two-phase lattice Boltzmann method (LBM) is used to study the natural convection heat exchange characteristics of Al2O3–H2O nanofluids and...