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941.
考虑具有范数有界不确定性的离散马尔可夫跳跃广义系统的严格耗散性分析和控制问题.首先将严格耗散概念引入到离散马尔可夫跳跃广义系统,利用线性矩阵不等式给出了离散马尔可夫跳跃广义系统鲁棒随机容许且严格耗散的充分条件;然后利用矩阵不等式给出了状态反馈鲁棒严格耗散控制器的存在条件和综合方法.最后通过数值算例说明了所提出方法的有效性.  相似文献   
942.
§ 1.IntroductionandMainResults InthispaperweusethestandardnotationsoftheNevanlinnatheoryofmeromorphicfunctionsoralgebroidfunctions.Forreferenceseee.g.[1 ] . Considerthegeneralizedhigher orderalgebraicdifferentialequationΩ1(z,w)Ω2 (z,w) =P(z,w)Q(z,w) , ( 1 )whereΩ1(z,w) =∑…  相似文献   
943.
高凌云 《数学季刊》2001,16(1):20-25
利用亚纯函数的Nevanlinna值分布理论,我们研究了一般复微分方程式代数体允许解的存在性问题,得到了一些结要。  相似文献   
944.
The compensation effect or Meyer-Neldel rule has been observed in a wide range of phenomena. It seems to be a fundamental property of the many families of activated processes following an Arrhenius dependence on temperature. The kinetic properties of grain boundaries and triple junctions depend strongly on their crystallographic parameters and obey the Arrhenius law. The data on the Meyer-Neldel rule for grain boundaries and triple junctions in Al and Zn and the values of the compensation temperature for the migration of grain boundaries and triple junctions are presented in this paper.  相似文献   
945.
We find an explicit basis for all admissible rules of the modal logic S4. Our basis consists of an infinite sequence of rules which have compact and simple, readable form and depend on increasing set of variables. This gives a basis for all quasi‐identities valid in the free modal algebra ℱS4(ω) of countable rank.  相似文献   
946.
Let B be a real JBW*–triple with predual B* and canonical hermitification the JBW*–triple A It is shown that the set 𝒰(B) consisting of the partially ordered set 𝒰(B) of tripotents in B with a greatest element adjoined forms a sub–complete lattice of the complete lattice 𝒰(A)of tripotents in A with the same greatest element adjoined. The complete lattice 𝒰(B) is shown to be order isomorphic to the complete lattice ℱn(B*1 of norm–closed faces of the unit ball B*1 in B* and anti–order isomorphic to the complete lattice ℱw*(B1) of weak*–closed faces of the unit ball B1 in B. Consequently, every proper norm–closed face of B*1 is norm–exposed (by a tripotent) and has the property that it is also a norm–closed face of the closed unit ball in the predual of the hermitification of B. Furthermore, every weak*–closed face of B1 is weak*–semi–exposed, and, if non–empty, of the form u + B0(u)1 where u is a tripotent in B and B0(u)1 is the closed unit ball in the zero Peirce space B0(u) corresponding to u. A structural projection on B is a real linear projection R on B such that, for all elements a and b in B, {Ra b Ra}B is equal to R{a Rb a}B. A subspace J of B is said to be an inner ideal if {J B J}B is contained in J and J is said to be complemented if B is the direct sum of J and the subspace Ker(J) defined to be the set of elements b in B such that, for all elements a in J, {a b a}B is equal to zero. It is shown that every weak*–closed inner ideal in B is complemented or, equivalently, the range of a structural projection. The results are applied to JBW–algebras, real W*–algebras and certain real Cartan factors.  相似文献   
947.
A notion of admissible probability measures μ on a locally compact Abelian group (LCA ‐ group) G with connected dual group Ĝ = ℝd × 𝕋n is defined. To such a measure μ, a closed semigroup Λ(μ) ⊆ (0, ∞) can be associated, such that, for t ∈ Λ(μ), the Fourier transform to the power t, (μˆ)t, is a characteristic function. We prove that the existence of roots for non admissible probability measures underlies some restrictions, which do not hold in the admissible case. As we show for the example ℤ2, in the case of LCA ‐ groups with non connected dual group, there is no canonical definition of the set Λ(μ).  相似文献   
948.
We are interested in the sizes of cliques that are to be found in any arbitrary spanning graph of a Steiner triple system 𝒮. In this paper we investigate spanning graphs of projective Steiner triple systems, proving, not surprisingly, that for any positive integer k and any sufficiently large projective Steiner triple system 𝒮, every spanning graph of 𝒮 contains a clique of size k. © 2000 John Wiley & Sons, Inc. J Combin Designs 8: 157–165, 2000  相似文献   
949.
In this paper, we solve numerically kinetic equations for the chain reactions of μCF in triple H/D/T mixture. Regarding the computational results, we show that μCF efficiency decreases by adding hydrogen H to D/T mixture. This is in contradiction to the usual belief which expects the increase of μCF efficiency in H/D/T mixture. Our results are confirmed by the first and recent experiment on μdt cycling rate in the triple mixture. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
950.
三效吸收制冷循环的性能分析和优化   总被引:6,自引:0,他引:6  
本文建立了使用溴化锂溶液作为工质的三种流程的三级三效吸收制冷循环模型,进行了性能比较计算,结果表明并联流程循环的性能系数COP最高;同时本文进一步对并联流程和串联流程的三效吸收制冷循环分别进行了关于溶液分配率和总体热交换面积分配率的优化计算,得到了不同设计工况时面积分配率与COP的关系,为三效吸收循环的最优设计提供了理论依据。  相似文献   
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