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951.
Wei Meng 《代数通讯》2013,41(3):909-915
Let G be a finite group and τ(G) denote the number of conjugacy classes of all non-abelian subgroups of G. The symbol π(G) denotes the set of the prime divisors of |G|. In this paper, finite groups with τ(G) ≤ |π(G)| are classified completely. Furthermore, finite nonsolvable groups with τ(G) = |π(G)| +1 are determined.  相似文献   
952.
基于锆基质与磷脂之间强烈的路易斯酸碱作用,制备了锆镁磷脂膜色谱固定相,并使用红外光谱、X射线光电子能谱对该色谱固定相进行了表征;使用与体内环境类似的生理缓冲液体系为流动相,评价了该模拟生物膜色谱固定相预测药物膜渗透性的能力,结果表明药物在锆镁磷脂膜色谱中的保留(log Kmbm)与表观渗透率(log Papp)在预测药物的膜渗透性、跨膜吸收等方面具有非常好的相关性,相关系数为0.970,斜率接近1。通过理论推导,引入了直观、方便的热力学指标吉布斯自由能差值(Δ(ΔG°))对药物-膜之间的相互作用强弱进行了评价。  相似文献   
953.
瞿萌  束立生 《数学研究》2005,38(2):129-132
作者得到了粗糙核分数次积分算子的两权弱型不等式,推广了Cruz-Uribe和Perez的结果.  相似文献   
954.
The paper is concerned with a stochastic optimal control problem in which the controlled system is described by a fully coupled nonlinear forward-backward stochastic differential equation driven by a Brownian motion. It is required that all admissible control processes are adapted to a given subfiltration of the filtration generated by the underlying Brownian motion. For this type of partial information control, one sufficient (a verification theorem) and one necessary conditions of optimality are proved. The control domain need to be convex and the forward diffusion coefficient of the system can contain the control variable. This work was partially supported by Basic Research Program of China (Grant No. 2007CB814904), National Natural Science Foundation of China (Grant No. 10325101) and Natural Science Foundation of Zhejiang Province (Grant No. Y605478, Y606667)  相似文献   
955.
In this paper, by virtue of two intermediate derivative-like multifunctions, which depend on an element in the intermediate space, some exact calculus rules are obtained for calculating the derivatives of the composition of two set-valued maps. Similar rules are displayed for sums. Moreover, by using these calculus rules, the solution map of a parametrized variational inequality and the variations of the feasible set of a parametrized mathematical programming problem are studied. This research was partially supported by the National Natural Science Foundation of China (Grant numbers: 10871216 and 60574073).  相似文献   
956.
We introduce the operator-valued free Fisher information for a random variable in an operator-valued noncommutative probability space and point out its relations to the amalgamated freeness. Using M. Frank and D. Larson's modular frame notion we can construct the conjugate variable for an operator-valued semicircle variable with conditional expectation covariance. Then we obtain its free Fisher information and show it is equal to the index of the conditional expectation. At last the conjugate variable with respect to a modular frame operator for a semicircle variable is also constructed.

  相似文献   

957.
Using a generalization of Sturm’s comparison theorem, some new oscillation criteria are established for the matrix differential system with damping
(P(t)Y)+R(t)Y+Q(t)Y=0(P(t)Y)+R(t)Y+Q(t)Y=0
under the hypothesis: P(t)=P(t)>0P(t)=P(t)>0, Q(t)=Q(t)Q(t)=Q(t), Y(t)Y(t) are n×nn×n matrices of real valued continuous functions on the interval [t0,∞)[t0,), and R(t)=R(t)∈C1([t0,∞),Rn2)R(t)=R(t)C1([t0,),Rn2). Our results are sharper than some previous results.  相似文献   
958.
This paper addresses a novel competitive facility location problem about a firm that intends to enter an existing decentralized supply chain comprised of three tiers of players with competition: manufacturers, retailers and consumers. It first proposes a variational inequality for the supply chain network equilibrium model with production capacity constraints, and then employs the logarithmic-quadratic proximal prediction–correction method as a solution algorithm. Based on this model, this paper develops a generic mathematical program with equilibrium constraints for the competitive facility location problem, which can simultaneously determine facility locations of the entering firm and the production levels of these facilities so as to optimize an objective. Subsequently, a hybrid genetic algorithm that incorporates with the logarithmic-quadratic proximal prediction–correction method is developed for solving the proposed mathematical program with an equilibrium constraint. Finally, this paper carries out some numerical examples to evaluate proposed models and solution algorithms.  相似文献   
959.
We investigate a system whose basic warranty coverage is minimal repair up to a specified warranty length. An additional service is offered whereby first failure is restored up to the consumers’ chosen level of repair. The problem is studied under two system replacement strategies: periodic maintenance before and after warranty. It turns out that our model generalizes the model of Rinsaka and Sandoh [K. Rinsaka, H. Sandoh, A stochastic model with an additional warranty contract, Computers and Mathematics with Applications 51 (2006) 179–188] and the model of Yeh et al. [R.H. Yeh, M.Y. Chen, C.Y. Lin, Optimal periodic replacement policy for repairable products under free-repair warranty, European Journal of Operational Research 176 (2007) 1678–1686]. We derive the optimal maintenance period and optimal level of repair based on the structures of the cost function and failure rate function. We show that under certain assumptions, the optimal repair level for additional service is an increasing function of the replacement time. We provide numerical studies to verify some of our results.  相似文献   
960.
Nonlinear responses of a rub-impact overhung rotor   总被引:1,自引:0,他引:1  
For a rotor system with bearings and step-diameter shaft in the oxygen pump of an engine, the contact between the rotor and the case is considered, and the chaotic response and bifurcation are investigated. The system is divided into elements of elastic support, shaft and disk, and based on the transfer matrix method, the motion equation of the system is derived, and solved by Newmark integration method. It is found that hardening the support can delay the occurrence of chaos. When rubbing begins, the grazing bifurcation will cause periodic motion to become quasi-period. With variation of system parameters, such as rotating speed, imbalance and external damping, chaotic response can be observed, along with other complex dynamics such as period- doubling bifurcation and torus bifurcation in the response.  相似文献   
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