Preparing of coherent superposition state in serial multi-A-type system by stimulated Raman adiabatic passage

A scheme for creating an arbitrary coherent superposition of two atomic states in serial multi-A-type system is proposed.This technique with the application of a control field is based on the existence of two degenerate dark states and their interaction.The mixing of the dark states can be controlled by changing the relative delay time of the control pulse.One can get any desired superposition by changing the delay time of the control pulse.     

Simulation and design consideration of photoresponse for HgCdTe infrared photodiodes

We report on 2D numerical simulations of photoresponse characteristic for long-wavelength HgCdTe infrared photodiodes. Effects of thickness of absorption layer on the photoresponse have been investigated. Optimal thickness of absorption layers at different absorption lengths and diffusion lengths are extracted numerically. An empirical formula is proposed to predict reasonable optimal thickness of absorption layer by theoretically analyzing its correlations with absorption lengths and diffusion lengths.     

Mixed integer programming models for dispatching vehicles at a container terminal

This paper presents scheduling models for dispatching vehicles to accomplish a sequence of container jobs at the container terminal, in which the starting times as well as the order of vehicles for carrying out these jobs need to be determined. To deal with this scheduling problem, three mixed 0–1 integer programming models, Model I, Model II and Model III are provided. We present interesting techniques to reformulate the two mixed integer programming models, Model I and Model II, as pure 0–1 integer programming problems with simple constraint sets and present a lower bound for the optimal value of Model I. Model III is a complicated mixed integer programming model because it involves a set of non-smooth constraints, but it can be proved that its solutions may be obtained by the so-called greedy algorithm. We present numerical results showing that Model III is the best among these three models and the greedy algorithm is capable of solving large scale problems.     

Asymptotic stability of nonlinear wave for the compressible Navier-Stokes equations in the half space

In the present paper, we investigate the large-time behavior of the solution to an initial-boundary value problem for the isentropic compressible Navier-Stokes equations in the Eulerian coordinate in the half space. This is one of the series of papers by the authors on the stability of nonlinear waves for the outflow problem of the compressible Navier-Stokes equations. Some suitable assumptions are made to guarantee that the time-asymptotic state is a nonlinear wave which is the superposition of a stationary solution and a rarefaction wave. Employing the L²-energy method and making use of the techniques from the paper [S. Kawashima, Y. Nikkuni, Stability of rarefaction waves for the discrete Boltzmann equations, Adv. Math. Sci. Appl. 12 (1) (2002) 327-353], we prove that this nonlinear wave is nonlinearly stable under a small perturbation. The complexity of nonlinear wave leads to many complicated terms in the course of establishing the a priori estimates, however those terms are of two basic types, and the terms of each type are “good” and can be evaluated suitably by using the decay (in both time and space variables) estimates of each component of nonlinear wave.     

On successive coefficients of odd univalent functions

The relative growth of successive coefficients of odd univalent functions is investigated. We prove that a conjecture of Hayman is true.

     

High power 1.3414 μm Nd:YAP cw laser

The eigen-oscillation mode of the Nd:YAP cw laser has been analysed. The influence of thermal effects arising from the pumping process on the output character of the 1.3414 μm Nd:YAP cw laser has been discussed. The crack problem of the reflective film at a 1.34 μm dielectric mirror has been solved. Based on the aforementioned work, we have been able to achieve an 82.8 W laser output at 1.3414 μm with a nearly polarized beam from a 5.8 mm diameter by 111 mm Nd:YAP rod. The overall efficiency and the slope efficiency are 1.15% and 2.02% respectively, and the fluctuation of the output power at 62 W is less than 1% during continuous operation for 45 min.     

The group Hom(<Emphasis Type="Italic">A,B</Emphasis>) as an Artinian E(<Emphasis Type="Italic">B</Emphasis>)-or E(<Emphasis Type="Italic">A</Emphasis>)-module

The conditions of Artinianity of the homomorphism group Hom(A, B) as a module over the endomorphism ring of the Abelian group B or A are found. __________ Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 13, No. 3, pp. 81–96, 2007.     

ON THE FREE VIBRATION OF A SUBMERGED FGM HOLLOW SPHERE

The free vibration of a functionally graded material hollow sphere submerged in a compressible fluid medium is exactly analyzed. The sphere is assumed to be spherically isotropic with material constants being inhomogeneous along the radial direction. By employing a separation technique as well as the spherical harmonics expansion method, the governing equations are simplified to an uncoupled second-order ordinary differential equation, and a coupled system of two such equations. Solutions to these equations are given when the elastic constants and the mass density are power functions of the radial coordinate. Numerical examples are finally given to show the effect of the material gradient on the natural frequencies. The project is supported by the National Natural Sciences Foundation of China(No. 19872060).     

连续调节反衬度观察位相物体的新方法

在4F系统中,利用光栅可以完成位相振幅转换,能够实现连续调节反衬度,因而观察位相物体的各部分就更清楚。一、引言观察透明的位相物体,必需把位相的信息转换