Let G be a finite group with the property that for any conjugacy class order, G has exactly two conjugacy classes which have the same order. We prove that： （1） ff a Sylow 2-subgroup of G is Abelian, then G is isomo...Let G be a finite group with the property that for any conjugacy class order, G has exactly two conjugacy classes which have the same order. We prove that： （1） ff a Sylow 2-subgroup of G is Abelian, then G is isomorphic to the direct product of symmetric group with order 3 and cyclic group with order 2, or G is isomorphic to the semidirect product of a cyclic group with order 3 and a cyclic group with order 4; （2） if G＇ is nilpotent, then G is a group of {2,3,5 }.展开更多
It is a new research topic to create a rational judgment matrix using the cognition theory because of the construction of judgment matrix in AHP involving the decision-maker's cognitive activities. Owing to the pr...It is a new research topic to create a rational judgment matrix using the cognition theory because of the construction of judgment matrix in AHP involving the decision-maker's cognitive activities. Owing to the presence of uncertain information in the decision procedure, the improper use of the uncertain information will doubtless cause weight changes. In this paper, we add a feedforward process prior to constructing the judgment matrix so that the decision maker can use both the certain and uncertain information to get the initial uncertain rough judgment matrix, and then convert it into a fuzzy matrix. Consequently, it will be better for decision maker to obtain the rough set of order equivalent classes through the decision graph. According to the qualitative analysis, the decision maker can easily construct the final judgment matrix instructed by the rough set created earlier.展开更多
§1.IntroductionThis paper deals with linear partial differential operators with real principalsymbol.Let P(x,D)be such an operator of mth order with C~∞ coefficients definedin an open subset Ω of R^n and p_m(x,...§1.IntroductionThis paper deals with linear partial differential operators with real principalsymbol.Let P(x,D)be such an operator of mth order with C~∞ coefficients definedin an open subset Ω of R^n and p_m(x,ξ)be its principal symbol.According to thedefinition given by Duistermaat and Hmander(see[1]),P(x,D)is called ofprincipal type at x^0 ∈Ω if for any ξ∈R^n\0 satisfying p_m(x^0,ξ)=0,x=x^0 is not theprojection in Ω of the bicharacteristic strip of P(x,D)through(x^0,ξ).Under thiscondition,they proved that there exists a neighborhood U of x^0,U,such that forany real number s,展开更多
In this paper we discuss the types and criteria of nonoscillatory solutions for the fol-lowing second order neutral functional differential equation with nonpositive coefficients
基金The Natural Science Foundation ofChongqing Education Committee (No.KG051107)
文摘Let G be a finite group with the property that for any conjugacy class order, G has exactly two conjugacy classes which have the same order. We prove that： （1） ff a Sylow 2-subgroup of G is Abelian, then G is isomorphic to the direct product of symmetric group with order 3 and cyclic group with order 2, or G is isomorphic to the semidirect product of a cyclic group with order 3 and a cyclic group with order 4; （2） if G＇ is nilpotent, then G is a group of {2,3,5 }.
基金This work is supported in part by the National Natural Sciences Fund Council, P. R. China, under Grant No. NSFC 6027047
文摘It is a new research topic to create a rational judgment matrix using the cognition theory because of the construction of judgment matrix in AHP involving the decision-maker's cognitive activities. Owing to the presence of uncertain information in the decision procedure, the improper use of the uncertain information will doubtless cause weight changes. In this paper, we add a feedforward process prior to constructing the judgment matrix so that the decision maker can use both the certain and uncertain information to get the initial uncertain rough judgment matrix, and then convert it into a fuzzy matrix. Consequently, it will be better for decision maker to obtain the rough set of order equivalent classes through the decision graph. According to the qualitative analysis, the decision maker can easily construct the final judgment matrix instructed by the rough set created earlier.
文摘§1.IntroductionThis paper deals with linear partial differential operators with real principalsymbol.Let P(x,D)be such an operator of mth order with C~∞ coefficients definedin an open subset Ω of R^n and p_m(x,ξ)be its principal symbol.According to thedefinition given by Duistermaat and Hmander(see[1]),P(x,D)is called ofprincipal type at x^0 ∈Ω if for any ξ∈R^n\0 satisfying p_m(x^0,ξ)=0,x=x^0 is not theprojection in Ω of the bicharacteristic strip of P(x,D)through(x^0,ξ).Under thiscondition,they proved that there exists a neighborhood U of x^0,U,such that forany real number s,
文摘In this paper we discuss the types and criteria of nonoscillatory solutions for the fol-lowing second order neutral functional differential equation with nonpositive coefficients
