Creep behaviour study of virgin and service exposed 5Cr–0.5Mo steel using magnetic Barkhausen emissions technique

Creep damage behaviour of water quenched 5Cr–0.5Mo steel has been studied using magnetic Barkhausen emissions (MBE) technique. The results were compared with the materials having same composition but used in service for 15 years to demonstrate the potentiality of the magnetic technique for in-situ evaluation of extent of creep damage of components. The rms voltage of magnetic Barkhausen signal for the virgin sample decreased at the initial stage of the expended creep life where new carbides are formed. As soon as the growth of the carbides took place at the expense of the smaller ones, MBE voltage started increasing due to the decrease of pinning density. However, in case of 15 years of service exposed sample, growth of carbides already took place and hence MBE voltage increased even during the initial stage of laboratory creep testing. As soon as the void started forming in the samples (both for virgin and service exposed one), the rate of increase of MBE voltage started decreasing. The formations of such cavities were observed through SEM micrograph analysis.     

An evolutionary approach to rehabilitation patient scheduling: A case study

Focusing on real settings, this study aimed to develop an evolutionary approach based on genetic algorithm for solving the problem of rehabilitation patient scheduling to increase service quality by reducing patient waiting time and improve operation efficiency by increasing the therapy equipment utilization. Indeed, due to partial precedence constraints of rehabilitation therapies, the problem can be structured as a hybrid shop scheduling problem that has received little attention to date. In addition, a mixed integer programming model was also constructed as a benchmark to validate the solution quality with small problems. Based on empirical data from a Medical Center in Taiwan, several experiments were conducted to estimate the validity of the proposed algorithm. The results showed that the proposed algorithm can reduce patient waiting time and enhance resource utilization and thus demonstrated the practicality of the proposed algorithm. Indeed, a decision support system embedded with the developed algorithm has been implemented in this medical center.     

高校图书馆流通阅览服务创新策略研究

提出了高校图书馆流通阅览服务创新导向,通过引进文献服务技术和设备、调整人员走向、调整藏书发展模式、提升读者活动层次、拓展志愿者队伍等措施加速图书馆服务创新进程。     

FDL干电池放电容量测试仪的研制

现行干电池的国家标准和行业标准［１～５］中对放电容量规定了一种或一种以上的放电试验，但均采用间歇放电和连续放电的方法进行试验．现行的国际标准和国家标准与行业标准相比，许多品种如Ｒ６Ｃ等均增加脉冲试验，这几个品种的电池又是目前市场上的畅销产品，市场增长的潜力很大．增加脉冲试验的原因主要有：１）间歇放电时间长，对产品符合性试验的判断需要较长的时间，而脉冲试验则大大缩短了检测时间，提高了效率；２）脉冲试验很好地模拟了传呼机等信息技术产品真实的工作状态，脉冲试验对产品的检验有极强的指导作用和现实意义．因…     

On the service performance of alternative shipment consolidation policies

In order to compare the performances of alternative shipment consolidation policies, we develop closed-form expressions of the distribution of the maximum waiting time and the average order delay. We examine the tradeoff between the expected delivery frequency, as measured by the expected shipment consolidation cycle length, and the average order delay. The previous analytical results regarding shipment consolidation are aimed at optimizing the performances of alternative policies using cost-based criteria whereas our results are useful under service-based criteria.     

A systematic approach on service life prediction of a model aerostat envelope

Lighter-than-air (LTA) helium aerostats are receiving renewed attention for scientific as well as defense applications. Designing of new and improved materials for this kind of structure that consistently survive in the harsh atmospheric condition is one of the critical issues. However, durability of a newly developed material, in the actual field of application, is often unknown. Field experiments to know about its service life take prolonged time. In this study, a systematic approach has been proposed to predict the in service weatherability of a model aerostat envelope. A reliability model with two stress types (UV radiation and temperature) has been achieved to predict the service life of a model aerostat envelope material concerning the gas permeability through the material. Accelerated aging tests at higher stress levels have been performed to obtain a life stress relationship from which service life of the material has been determined at the use level conditions. Validation of the proposed model has also been performed using the actual field test data. It will be worthy to apply this approach in various fields of application to predict the service life of newly developed materials before their commercialization.     

Optimizing daily agent scheduling in a multiskill call center

We examine and compare simulation-based algorithms for solving the agent scheduling problem in a multiskill call center. This problem consists in minimizing the total costs of agents under constraints on the expected service level per call type, per period, and aggregated. We propose a solution approach that combines simulation with integer or linear programming, with cut generation. In our numerical experiments with realistic problem instances, this approach performs better than all other methods proposed previously for this problem. We also show that the two-step approach, which is the standard method for solving this problem, sometimes yield solutions that are highly suboptimal and inferior to those obtained by our proposed method.     

基于Windows 2000流式媒体技术的远程教育系统

在介绍现代远程教育和Ｗｉｎｄｏｗｓ２０００ Ｍｅｄｉａ Ｓｅｒｖｉｃｅ技术的基础上，给出了一种基于流式媒体技术的远程教育系统的解决方案。分析了系统的组成、课件昨子系统、应用的网络环境和客户端软件，包括点播服务及多点广播服务的系统工作模式，最后介绍了系统的应用前景。     

高职图书馆专业群馆员服务模式的研究与探索

知识经济时代的迅猛发展,使得高职图书馆的用户需求与馆员服务的矛盾越来越突出,成为一个刻不容缓的研究课题。本文从发展的角度出发,阐述了专业群馆员服务模式的概念和实施意义,并就专业群馆员服务模式的建设策略进行了分析与探索。     

基于Android的移动学习系统中Web Service的构建与实现

移动学习系统中,客户端与服务器端之间能够进行高效的信息交互是需要解决的一个重要问题。在移动客户端OS为Android系统且服务端由Java EE应用实现的情况下,设计了移动学习系统的结构,并利用CXF框架在服务端创建Web Service,实现客户端与服务器端的信息交互。通过框架配置文件的设置,实现了CXF与Java EE的控制框架Spring的相互结合,为客户端提供高效的、可扩展性较好的Web Service。