Laser Diode-Pumped Nd：LuVO4 Acousto-Optic Q-Switched Laser at 916 nm

A compact laser diode-pumped solid-state Nd：LuVO4 acousto-optic Q-switched laser is demonstrated at 916 nm of a quasi-three level for the first time. A pulse width of 130ns is observed when the pulse-repetition frequency is 10 kHz. The laser experiment shows that the Nd：Lu VO4 crystal can be used for efficient diode-pumped Q-switched lasers.     

A Two-Phase Cyclic Nonhomogeneous Markov Chain Performability Evaluation by Explicit Approximate Inverses Applied to a Replicated Database System

The need for a more accurate modeling of the performance of systems whose functioning mainly dependant on external time parameters such as the number of requests during a particular time phase, led us to a novel approach, taking into account the time parameters involved. This is achieved through the evaluation of a performability indicator modeled by means of a two-phase cyclic nonhomogenous Markov chain considering periodical time-dependant arrival request probabilities and applied to a replicated database system. The computation of the performability indicator modeled by cyclic nonhomogeneous Markov chain requires the use of efficient computational methods by using explicit approximate inverse preconditioning methods. This revised version was published online in July 2006 with corrections to the Cover Date.     

Software rejuvenation and resource reservation policies for optimizing server resource availability using cyclic nonhomogeneous Markov chains

Software rejuvenation is modeled in a client–server system, which provides resources to priority classes of users. To assure availability, resource reservation policies are adopted for the higher priority classes. In addition software rejuvenation is proposed to optimize resource availability. The system is modeled by a cyclic nonhomogeneous Markov chain to capture the variation of the arrival and service rates during a day period. An optimization problem is solved based on a similar previous work and given the optimal resource reservation policy obtained by its solution, rejuvenation is performed and the optimal rejuvenation policy is determined. As a measure of resource availability the blocking probability of each priority class is used. Performability indicators expressing the total cost are also derived, with respect to the optimal resource reservation and optimal rejuvenation policies, to examine whether rejuvenation benefits the system in terms of cost. To derive the blocking probabilities, the limiting probability distribution is computed using explicit generalized approximate inverse preconditioning for solving efficiently sparse linear systems of algebraic equations. Copyright © 2012 John Wiley & Sons, Ltd.     

Domain Decomposition–Finite Difference Approximate Inverse Preconditioned Schemes for Solving Fourth-Order Equations

A new class of explicit approximate inverse preconditioning is introduced for solving fourth-order equations, based on the coupled equation approach, by the domain decomposition method in conjunction with various finite difference approximation schemes. Explicit approximate inverse arrow-type matrix techniques, based on the concept of sparse L U-type factorization procedures, are introduced for computing a class of approximate inverses. Explicit preconditioned conjugate gradient-type schemes are presented for the efficient solution of linear systems. Applications of the method to a biharmonic problem are discussed and numerical results are given.     

电感耦合等离子体原子发射光谱法测定马奶酒中的多种元素

电感耦合等离子体原子发射光谱法测定马奶酒中的多种元素嘎日迪,乌地（内蒙古师范大学化学系,配位化学研究所,呼和浩特,０１００２２）关键词电感耦合等离子体原子发射光谱,马奶酒,微量金属元素蒙古民族喜爱的传统饮料──马奶酒（蒙语“策格”）是用鲜马奶为原料发...     

抗阿尔兹海默症藏药三味豆蔻汤的化学成分分析研究

三味豆蔻汤作为藏药的经典方剂,由药材豆蔻、香旱芹、荜茇和牦牛奶熬煮制成,其对阿尔兹海默症(Alzheimer's disease,AD)具有一定的治疗作用.该方剂化学成分复杂且极性、挥发性差异大,相关的物质基础研究较少.该研究分别采用气相色谱-质谱(GC-MS)、超高效液相色谱-高分辨串联质谱(UPLC-HRMS/MS...     

加速度环境下微槽流动与传热特性

航空电子设备在加速度环境下工作时,采用液体工质进行散热的电子设备的散热性能将受到加速度的影响。本文采用有限体积法对加速度环境下矩形微槽中体积浓度30%的乙二醇水溶液的流动和传热特性进行了系统研究。考察了加速度大小和方向对微槽中流动与传热特性的影响,以及加速度环境对不同微槽结构和工质流量下流动与传热特性的影响。研究表明,与不考虑加速度影响时相比,在开始的瞬间,微槽传热性能大幅降低,流动阻力系数急剧上升,     

基于SEM的我国重要城市现代化水平综合评价模型研究

基于结构方程(SEM)理论,以2008年统计数据为样本对影响城市现代化的测量指标进行了一阶、二阶验证性因素分析,得到了结构方程模型.并以测量指标在因子上的负荷、路径系数为基础构建权重,建立了城市现代化水平综合评价模型.对我国重要城市(直辖市、主要省会城市)现代化水平程度进行了相对评价,得到较为满意的结果.     

Contents of Volume 1 (2002)

Volume Contents

Contents of Volume 1 (2002)