A UNIFORM FIRST-ORDER METHOD FOR THE DISCRETE ORDINATE TRANSPORT EQUATION WITH INTERFACES IN X,Y-GEOMETRY

A uniformly first-order convergent numerical method for the discrete-ordinate transport equation in the rectangle geometry is proposed in this paper. Firstly we approximate the scattering coefficients and source terms by piecewise constants determined by their cell averages. Then for each cell, following the work of De Barros and Larsen [1, 19], the solution at the cell edge is approximated by its average along the edge. As a result, the solution of the system of equations for the cell edge averages in each cell can be obtained analytically. Finally, we piece together the numerical solution with the neighboring cells using the interface conditions. When there is no interface or boundary layer, this method is asymptotic-preserving, which implies that coarse meshes （meshes that do not resolve the mean free path） can be used to obtain good numerical approximations. Moreover, the uniform first-order convergence with respect to the mean free path is shown numerically and the rigorous proof is provided.     

Resistant effect of non-equilibrium inter-particle collisions on dense solids transport

There exist big gaps between measurements and modeling predictions on solids holdup and pressure drop in dense solids transport, such as those occuring in the bottom sections of gas-solids risers. The inability of closing this gap by common modeling approaches indicates certain missing and/or misrepresentation of some controlling mechanisms in modeling the transport. Previous research efforts show that the gap can not be effectively narrowed by simply modifying the drag force formulations without inclusion of the collision effect. This paper explores the origin of some controlling mechanisms that might have been overlooked in previous modeling approaches, and recommends how to make the model dense solids transport better. Our analysis shows the presence of a resistant force arising from inter-particle collision when the solids are accelerated in dense-phase transport. This may be caused by non-equilibrium collision during solids acceleration, which differs from local-equilibrium assumptions on which the current kinetic theory modeling of granular particles is based. A complete modeling of this collision-induced resistance calls for a total revision of the kinetic theory, with the inclusion of non-equilibrium collisions and offcenter collisions in dense solids transport.     

Conductance Oscillations in Spin Field-Effect Transistors

Ballistic spin transport in spin field-effect transistors is studied by taking into account the Rashba spinorbit coupling, interracial scattering, and band mismatch. It is shown that the spin conductance oscillation with the semiconductor channel length is a superimposition of the Rashba spin precession and spin interference oscillations. They have different oscillation periods π/κR and π/κ with κR the Rashba wavevector and κ the Fermi wavevector of the semiconductor channel, and play different parts of slow and rapid oscillations, depending upon the relative magnitude of π/κR and π/κ. Only at κ = κR does the spin conductance exhibit oscillations of a single period. Two types of different behaviors of the tunnelling magnetoresistance are discussed.     

Two-Qubit Logic Gates and Teleportation of an Entangled State of Atom-Cavity with Cavity QED

In this paper, a scheme is proposed for realization of two-qubit controlled-not gates and teleportation of an entangled state of atom-cavity. In this scheme, applying hyperfine levels of atom, we consider A-type three-level atom interacting resonantly or nonresonantly with cavity field that is prepared in σ- polarized. We consider the experimental feasibility of this scheme and compare our results with other schemes.     

钢管定购和运输的策略优化

本文为图 1主管道和图 2树形管道的定购和运输计划给出了一个最优化模型 .通过解这一个最优化模型得到钢管的定购和运输的最优策略 .同时 ,分析了哪个钢厂钢管销价的变化对图 1主管道购运计划和总费用影响最大 ,哪个钢厂钢管产量的上限的变化对购运计划和总费用影响最大     

推进剂用超声液位仪

一类发射体的推进剂具有剧毒,强腐蚀,易挥发,易燃易等特点,一般贮存在密封容器中,如运用通常的接触式仪器对其储罐中的液位进行检测,则仪器使用寿命很短,本文介绍了运输,贮存容器中的液位,能进行非接触式精确测量超声液位仪。     

带有模糊参数的运输期望值模型

基于可信性理论,将提出一类带有模糊参数的运输期望值模型.然后,讨论模糊运输期望值模型的基本性质.最后,给出一个数值例子来表明所设计模型的实用性.     

Teleportation of N-Particle Entangled GHZ State via Entanglement Swapping

In this scheme, N non-maximally entangled particle pairs are used as quantum channel to teleport an unknown N-particle entangled GHZ state via entanglement swapping. In order to realize this teleportation, the sender Alice operates Bell-state measurement on particles belonging to herself. Then she informs the results to the receiver Bob through classical communication. According to the results, Bob operates corresponding transformation to reconstruct the initial state. The advantage of this scheme is that it needs only one common unitary matrix for Alice＇s different results, which has a more general meaning. As a special case, teleporting an unknown three-particle entangled GHZ state is proposed.     

随机需求条件下的延迟发运策略模型及性质

本针对随机需求条件下物流配送中心的库存和运输联合决策问题，在基本库存和自身运输能力不足的情况下，提出对剩余客户订货需求采取部分延迟到下一期与部分利用第三方物流立即发运两相结合的策略，并在具有一般惩罚(损失)费延迟发运量限制的条件下，建立运输和库存相关总成本数学期望最小的优化模型，论证了该模型的主要性质，在此基础上很容易构造求解该类问题的优化方法。     

Probabilistic teleportation of an arbitrary three-particle state

A scheme for teleporting an arbitrary and unknown three-particle state from a sender to either one of two receivers is proposed. The quantum channel is composed of a two-particle non-maximally entangled state and two three-particle non-maximally entangled W states. An arbitrary three-particle state can be perfectly teleported probabilistically if the sender performs three generalized Bell-state measurements and sends to the two receivers the classical result of these measurements, and either one of the two receivers adopts an appropriate unitary transformation conditioned on the suitable measurement outcomes of the other receiver. All kinds of unitary transformations are given in detail.