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841.
Ranking fuzzy numbers with integral value 总被引:117,自引:0,他引:117
Ranking fuzzy numbers is important in decision making. Since very often the alternatives are evaluated by fuzzy numbers in a vague environment, a comparison between these fuzzy numbers is indeed a comparison between alternatives. This paper proposes a method of ranking fuzzy numbers with integral value. The method, which is independent of the type of membership functions used and the normality of the functions, can rank more than two fuzzy numbers simultaneously. It is relatively simple in computation, especially in ranking triangular and trapezoidal fuzzy numbers. Further, an index of optimism is used to reflect the decision maker's optimistic attitude. Discussion on comparative advantages is included. 相似文献
842.
E. C. Johnsen 《Linear and Multilinear Algebra》1974,1(4):343-356
In this paper we extend the general theory of essentially doubly stochastic (e.d.s.) matrices begun in earlier papers in this series. We complete the investigation in one direction by characterizing all of the algebra isomorphisms between the algebra of e.d.s. matrices of order n over a field F,En(F), and the total algebra of matrices of order n - 1over F,Mn-1(F) We then develop some of the theory when Fis a field with an involution. We show that for any e,f§Fof norm 1,e≠f every e.d.s. matrix in En(F) is a unique e.d.s. sum of an e.d.s. e-hermitian matrix and an e.d.s. f-hermitian matrix in En(F) Next, we completely determine the cases for which there exists an above-mentioned matrix algebra isomorphism preserving adjoints. Finally, we consider cogredience in En(F) and show that when such an adjoint-preserving isomorphism exists and char Mn(F) two e.d.s. e-hermitian matrices which are cogredient in Mn(F) are also cogredient in En(F). Using this result, we obtain simple canonical forms for cogredience of e.d.s. e-hermitian matrices in En(F) when Fsatisfies special conditions. This ncludes the e.d.s. skew-symmetric matrices, where the involution is trivial and E = -1. 相似文献
843.
The comparison of two theoretical approaches for the numerical investigation of turbulent gas–solid flows with heat transfer in a pipe are presented in this paper. The first approach is based on Eulerian–Eulerian modelling of investigated phenomena, the second one is formulated within the framework of the Eulerian–Lagrangian approach. The verification of numerical models under consideration. Their testing against available experimental data show good prognostic properties of the elaborated theoretical tool for research activities to study new physical fundamentals of turbulent gas-suspended particles flows in pipes and channels. 相似文献
844.
Recently it has been demonstrated that, on the basis of the separation D=De+Dp arising from the split of the stress power and two consistency criteria for objective Eulerian rate formulations, it is possible to establish a consistent Eulerian rate formulation of finite elastoplasticity in terms of the Kirchhoff stress and the stretching, without involving additional deformation-like variables labelled “elastic” or “plastic”. It has further been demonstrated that this consistent formulation leads to a simple essential structure implied by the work postulate, namely, both the normality rule for plastic flow Dp and the convexity of the yield surface in Kirchhoff stress space. Here, we attempt to place such an Eulerian formulation on the thermodynamic grounds by extending it to a general case with thermal effects, where the consistency requirements are treated in a twofold sense. First, we propose a general constitutive formulation based on the foregoing separation as well as the two consistency criteria. This is accomplished by employing the corotational logarithmic rate and by incorporating an exactly integrable Eulerian rate equation for De for thermo-elastic behaviour. Then, we study the consistency of the formulation with thermodynamic laws. Towards this goal, simple forms of restrictions are derived, and consequences are discussed. It is shown that the proposed Eulerian formulation is free in the sense of thermodynamic consistency. Namely, a Helmholtz free energy function in explicit form may be found such that the restrictions from the thermodynamic laws can be fulfilled with positive internal dissipation for arbitrary forms of constitutive functions included in the constitutive formulation. In particular, that is the case for the foregoing essential constitutive structure in the purely mechanical case. These results eventually lead to a complete, explicit constitutive theory for coupled fields of deformation, stress and temperature in thermo-elastoplastic solids at finite deformations. 相似文献
845.
于学刚 《应用数学和力学(英文版)》1998,19(12):1189-1195
Hyperbolic complex numbers correspond with Minkowski geometry. The hyperbolic Lagrangian equation and the Hamilton-Jacobi
equation will be derived from the invariants of four-dimensional space-time intervals and hyperbolic Lorentz transformations. 相似文献
846.
基于欧拉描述的两节点索单元非线性有限元法 总被引:13,自引:0,他引:13
本文针对柔性悬索结构几何非线性分析的特点,提出了一种用欧拉描述来表示的两节点索单元非线性有限元模型,在索元变形后的位置上由虚功能建立了非线有限元基本方程及切线刚度矩阵。这样建立的非线性有限元分析方法可充分考虑拉索的几何非线性特性的影响并给悬索结构的初始平衡分析带来方便,算例结果表明,本文方法是精确有效的。 相似文献
847.
We establish some new bounds on the log-covering numbers of (anisotropic) Gaussian reproducing kernel Hilbert spaces. Unlike previous results in this direction we focus on small explicit constants and their dependency on crucial parameters such as the kernel bandwidth and the size and dimension of the underlying space. 相似文献
848.
C. A. Kennedy S. N. MacMillan M. J. McAlduff D. G. Marangoni 《Colloid and polymer science》2001,279(1):1-7
The micelle formation process for a typical anionic surfactant, sodium dodecyl sulfate, and a typical cationic surfactant,
dodecyltrimethylammonium bromide, has been investigated in a series of mixed solvents consisting of different concentrations
of isomeric hexanediols (1,2-hexanediol and 1,6-hexanediol) in water. The critical micelle concentrations and the degrees
of counterion dissociation of the mixed micelles were obtained from conductance experiments. Luminescence probing experiments
have been used to determine the concentration of micelles in solution and, hence, the micellar aggregation numbers of the
surfactants in the mixed solvent systems. The alcohol aggregation numbers were determined by combining the partition coefficients
(obtained using NMR paramagnetic relaxation enhancement experiments) with the micellar concentrations from the luminescence
probing experiments. All these results are interpreted in terms of the difference in the interaction of the isomeric hexanediols
with the surfactant as a function of the position of the hydroxyl groups on the six-carbon chain of the alcohol.
Received: 28 June 2000/Accepted: 5 July 2000 相似文献
849.
N. R. Ivanov 《Phase Transitions》2013,86(1-4):223-232
An attempt is made to extend the method of experimental analysis of fluctuation behaviour at normal (N)—incommensurate (INC) phase transitions in the case of narrow INC-phases. Values of fluctuation parameters (the “effective Ginzburg Numbers”) for RbH3(SeO3)2 and RbD3(SeO3)2 crystals are suggested and compared with those of some other crystals from the A2BX4 family (G = 0.01 ÷ 0.036). In addition, in the crossover region the role of defects is clearly demonstrated by comparing the behaviour of incompletely deuterated crystal Rb(H, D)3(SeO3)2 with that of RbH3(SeO3)2. 相似文献
850.
本文考虑了由最高峰的高度为m,并且峰的高度沿着Dyck路严格递增的所有Dyck路组成的集合,即集合Dm的子集的计数问题.利用双射、生成树以及Riordan阵的方法来对集合Dm的一些子集进行计数,得到了一些以经典的序列如Catalan数、Narayana数、Motzkin数、Fibonacci数、Schroder数以及第一类无符号Stirling数来计数的组合结构.特别地,我们给出了两个新的Catalan结构,它们并没有明显地出现在Stanley关于Catalan结构的列表中. 相似文献