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141.
142.
一个模糊多目标群体决策方法 总被引:2,自引:1,他引:1
将多目标系统模糊决策理论推广到多目标标群体决策,给出一个模糊多目标群体决策方法。 相似文献
143.
企业对环境应变的和谐性分析 总被引:3,自引:0,他引:3
利用和谐理论原理及和谐分析矩阵,分析和判定企业对环境适应的和谐程度以及环境对企业的制约性,从而为企业进一步的决策奠定基础. 相似文献
144.
钱建国 《厦门大学学报(自然科学版)》1998,37(4):478-482
记A+∞(R,S)为具有行和向量R及列和向量S的所有m×n阶非负整数矩阵的集合.广义变换图G+∞(R,S)的顶点定义为A+∞(R,S)中的矩阵,两个顶点(矩阵)相邻当且仅当它们可通过一次变换相互得到.并证明G+∞(R,S)的边连通度等于其顶点的最小度δ(G+∞(R,S)). 相似文献
145.
不同去叶强度对羊草群落特征影响的研究 总被引:3,自引:1,他引:2
通过30%,50%,60%,80%去叶强度的试验研究,表明:7月份,不同去叶强度下群落的地上部生物量没有明显差异,8月份,30%,50%,60%的去叶处理,也没有明显差异,但80%处理的生物量却明显减少,9月份,各处理间地上部生物量差异很大,60%和80%的处理,生物量均低于30%和50%的处理7-9月份,随着去叶强度的增大,群落去叶的总收获量增加,枯落物的积累量逐渐减少,10月份,50%,60% 相似文献
146.
本文通过对黑生料球在不同煅烧温度下的残余碳、失重率及游离氧化钙等的测定,对立窑黑生料球的燃烧与反应特性进行了研究。认为黑生料球的燃烧大致可分为三个阶段。根据实验中游离钙的变化规律,并结合有关煅烧理论,肯定了黑生料煅烧的优越性。而实验中机械不完全燃烧现象,说明了“高灰分”对料球燃烧反应的影响,为实际生产控制提供了依据。 相似文献
147.
Choquet expected utility which uses capacities (i.e. nonadditive probability measures) in place of-additive probability measures has been introduced to decision making under uncertainty to cope with observed effects of ambiguity aversion like the Ellsberg paradox. In this paper we present necessary and sufficient conditions for stochastic dominance between capacities (i.e. the expected utility with respect to one capacity exceeds that with respect to the other one for a given class of utility functions). One wide class of conditions refers to probability inequalities on certain families of sets. To yield another general class of conditions we present sufficient conditions for the existence of a probability measureP with f dC= f dP for all increasing functionsf whenC is a given capacity. Examples includen-th degree stochastic dominance on the reals and many cases of so-called set dominance. Finally, applications to decision making are given including anticipated utility with unknown distortion function. 相似文献
148.
As the application of a dielectric theory proposed previously (J Membrane Sci 64:153–161 (1991)), theoretical formulation and the practical procedure of dielectric analysis are developed to calculate the structural parameters such as the conductivity gradient and the thickness of the concentration polarization layer, the capacitances and the conductances of the two adjoining aqueous phases from the observed dielectric parameters. The procedure of calculation consequent upon the theoretical formulation was applied to double relaxation data observed for cation-exchange membrane systems under application of d.c. bias voltage. As a consequence, the structural parameters of concentration polarization were readily obtained with accuracy. 相似文献
149.
Jakub Kołacz Henry G. Gotjen Robel Y. Bekele Jason D. Myers Jesse A. Frantz Michael Ziemkiewicz 《Liquid crystals》2020,47(4):531-539
ABSTRACTIn a planar dielectric waveguide, weak confinement of a propagating mode in a high index core leads to a measurable evanescent interaction with the cladding. In this work, we study the effect of a reorientable anisotropic cladding on the behaviour of Transverse Electric (TE) and Transverse Magnetic (TM) mode polarisations using a liquid crystal (LC)-clad waveguide architecture. The polarised evanescent field of a guided mode interacts with a voltage-tunable birefringent LC cladding to deflect an out-coupled beam. Experimental measurements are coupled with a theoretical framework and show good consistency with simulation results. We isolate the effect of mode confinement by changing the thickness of the high index core. Interactions between the LC index ellipsoid and the mode polarisation are probed by changing the initial alignment of the LC. Finally, we examine the difference in deflection between TE and TM modes, which incorporates both a change in mode confinement and a difference in LC index components. 相似文献
150.
Odin C 《Magnetic resonance in chemistry : MRC》2004,42(4):381-388
A variable-temperature high-resolution 13C and 87Rb solid-state NMR study of powder rubidium hydrogencarbonate, RbHCO3, is presented for the first time. At ambient temperature, RbHCO3 is formed by centrosymmetric dimers linked by hydrogen bonds, but almost no information is available on this compound concerning proton disorder and the low-temperature phase. However, potassium hydrogencarbonate, KHCO3, which has an isomorphic structure for the high temperature phase, was well studied: it undergoes a non-ferroic, non-ferroelectric phase transition at Tc = 318 K between two monoclinic structures. The protons are disordered in an asymmetric double-well potential in the low-temperature phase, and the double-well potential becomes symmetric in the high-temperature phase. By comparison with recent solid-state NMR experimental results on KHCO3, we show that RbHCO3 undergoes a phase transition at Tc approximately 245 K, and give evidence that the proton dynamic disorder in both compounds is very similar. 相似文献