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461.
462.
《European Journal of Operational Research》1997,101(2):230-244
A class of stochastic optimization problems is analyzed that cannot be solved by deterministic and standard stochastic approximation methods. We consider risk-control problems, optimization of stochastic networks and discrete event systems, screening irreversible changes, and pollution control. The results of Ermoliev et al. are extended to the case of stochastic systems and general constraints. It is shown that the concept of stochastic mollifier gradient leads to easily implementable computational procedures for systems with Lipschitz and discontinuous objective functions. New optimality conditions are formulated for designing stochastic search procedures for constrained optimization of discontinuous systems. 相似文献
463.
Teleportation of an Arbitrary Two-Particle State by Two Partial Entangled Three-Particle GHZ States 总被引:2,自引:0,他引:2
We present a scheme for teleporting an unknown arbitrary
two-particle state from a sender to either one of two receivers. The quantum
channel is composed of two partial entangled three-particle GHZ states. An
unknown arbitrary two-particle state can be perfectly teleported
probabilistically if the sender performs two generalized Bell-state
measurements and each receiver introduces an appropriate unitary
transformation with the help of the other receiver's Hadamard operations and
simple measurements. 相似文献
464.
DAI Hong-Yi KUANG Le-Man LI Cheng-Zu 《理论物理通讯》2005,44(7)
We propose a scheme to probabilistically teleport an unknown arbitrary three-level two-particle state by using two partial entangled two-particle states of three-level as the quantum channel. The classical communication cost required in the ideal probabilistic teleportation process is also calculated. This scheme can be directly generalized to teleport an unknown and arbitrary three-level K-particle state by using K partial entangled two-particle states of three-level as the quantum channel. 相似文献
465.
《Mathematical Social Sciences》1987,13(2):177-181
The τ-value is characterized by three axioms. It is shown that the τ-value is the unique solution concept which is efficient and has the minimal right property and the restricted proportionality property. The minimal right property is weaker than the additivity property, which plays a role in the axiomatic characterization of the Shapley value: together with individual rationality and efficiency additivity implies the minimal right property. The restricted proportionality property says that for games with minimal right vector zero, the dividend given to the players is proportional to the marginal contribution of the players to the grand coalition. 相似文献
466.
Motivated by the study of regularization for sparse problems,we propose a new regularization method for sparse vector recovery.We derive sufficient conditions on the well-posedness of the new regularization,and design an iterative algorithm,namely the iteratively reweighted algorithm(IR-algorithm),for efficiently computing the sparse solutions to the proposed regularization model.The convergence of the IR-algorithm and the setting of the regularization parameters are analyzed at length.Finally,we present numerical examples to illustrate the features of the new regularization and algorithm. 相似文献
467.
《European Journal of Mechanics - B/Fluids》2000,19(5):547-557
An account is given of the working life of the recently decommissioned axisymmetric turbulent-boundary-layer windtunnel in the Hermann-Föttinger-Institut of the Technische Universität Berlin, and some principal investigations conducted in it. 相似文献
468.
《International Journal of Solids and Structures》1999,36(23):3517-3539
Thermal residual-stresses introduced during manufacture and their effect on the natural frequencies and vibration modes of stringer stiffened composite plates is investigated. The principal idea in the work is to include stiffeners on the perimeter of a composite plate in which the laminate design of the stiffeners and plate are different. Such an arrangement yields manufacturing induced thermal residual-stresses; these stresses result from the difference in manufacturing and operating temperatures as well as the difference in thermal expansion coefficients and elastic properties of the plate and the stiffeners. The analysis is based on an enhanced Reissner–Mindlin plate theory and involves two separate calculations. In the first, the thermal residual-stress state is determined for an unconstrained plate. In the second, the free vibration problem is solved; thermal effects from the first calculation are included by way of nonlinear membrane-bending coupling which in turn defines the free vibration reference state. The problem is solved using a 16-node bi-cubic Lagrange element in a finite element formulation. Three different plate-stiffener geometries are used to illustrate the effects of stringer size, stringer placement and temperature difference. Two principal results are obtained: first, it is shown that thermal residual-stresses can have a significant effect on the natural frequencies; secondly, thermal residual-stresses can be tailored to increase natural frequencies. Therefore it is concluded that an evaluation of these stresses and a judicious analysis of their effects must be included in the design of this class of composite structures. 相似文献
469.
470.