Supply chain management with lean production and RFID application: A case study

This study applies lean production and radio frequency identification (RFID) technologies to improve the efficiency and effectiveness of supply chain management. In this study, a three-tier spare parts supply chain with inefficient transportation, storage and retrieval operations is investigated. Value Stream Mapping (VSM) is used to draw current state mapping and future state mapping (with lean production and RFID) with material, information, and time flows. Preliminary experiments showed that the total operation time can be saved by 81% from current stage to future stage with the integration of RFID and lean. Moreover, the saving in total operation time can be enhanced to 89% with cross docking. In addition, utilizing RFID technology, the cost of labors can be significantly reduced while maintaining current service capacity at the members in the studied supply chain. Return-on-investment (ROI) analysis shows that the proposed method is both effective and feasible.     

Identifying Strategies to Support Junior Secondary Students to Engage in Scientific Investigation Tasks

Abstract

This article describes the outcome of a collaborative project between the Hong Kong Institute of Education and four secondary schools that aims to promote the development of scientific investigation skills. The project team designed scientific investigation tasks collaboratively with the teachers and provided school-based support when the tasks were implemented. A total of six teachers and 575 students were involved. Data were collected through questionnaires completed by the students and individual interviews with science teachers about their classroom practice after the completion of the project. The findings suggest that the students did not meet many difficulties and that there were positive influences on students’ interest in learning science. The teachers perceived that there were challenges related to raising students’ self-regulated learning abilities, structuring tasks that were at appropriate levels of difficulty, and promoting group cooperation among the students. Finally, the article argues that the strategies implemented in this study were effective, though it takes much time and effort to help students develop self-regulated learning abilities. The conclusion suggests that teachers consider these challenges collectively and proposes a two-staged model for planning scientific investigation tasks.     

Evaluating interfaces with children

Children are very different from adults—they have developing motor skills, limited reach, short attention spans, limited exposure to traditional user interfaces and social protocols. How do we evaluate user interfaces for children? In this paper, we present four evaluative techniques that we have successfully used with children.     

信息技术背景下教师观念的更新与角色转换

当今世纪是以信息技术为标志的世纪。以计算机和网络技术为核心的现代信息技术的不断发展,传统教育观念和传统教师角色正面临着严峻的挑战。教师必须解放思想、更新观念,并对自身职业角色进行重新审视和定位。     

交流电机绕组分布系数推导方法的研究

对交流电机绕组分布系数推导的代数法进行了详尽描述,并对代数法与几何法进行了比较。     

电力企业管理标准体系的建设与完善

针对企业管理标准体系建设存在的问题,阐述了企业管理标准体系建设的指导原则,提出了企业管理标准体系建设过程需注意事项。     

基于IEC61850的万能式断路器模型构建

信息建模是IEC61850标准的核心内容,该标准规定了变电站信息模型和建模方法.首先,对IEC61850标准的特点进行了简要介绍,研究了基于IEC61850标准的建模技术,对智能电子设备的数据模型进行了分析,通过对服务器、逻辑设备、逻辑节点以及数据对象的分析,详细说明了智能电子设备的建模方法.然后,以万能式断路器为例进行了建模,完整地描述了断路器的功能,对功能进行了分解,以保护功能为例完成了对逻辑设备的建模,并对瞬时过流保护逻辑节点PIOC以及包括的数据对象Oper进行了建模,分别对各类数据对象和数据属性进行了说明.     

基于ARM处理器的数字PID伺服电机调速系统

介绍了基于ARM处理器的数字PID控制方式实现对直流伺服电机的调速。调速系统根据实际情况,采用了优化PID的算法并移植了μC/OS-Ⅱ实时操作系统,使得电机的调速性能在快速性、平稳性方面都得到了很大的提高。整个伺服控制系统结构简单、控制方便、实时性高,已经取得了良好的实验效果,可以满足电机高速高精度的运行要求。     

空冷岛内部流场的建模分析和试验对比

空冷岛作为一个空冷电厂的大型换热器,其性能与内外流场密切相关。对空冷岛内部流场进行了系统建模分析,并结合试验进行对比,对空冷岛内部流场的分布规律有了较为深入的理解,为进一步的优化提供了基础。给出了对应于试验结果的空冷岛凝结温度分布的原因及凝结压力分布、凝结流量分配计算结果。     

温度与时间对预灰过程的影响

通过对比实验分析,确定在预灰过程中,温度和时间对生产工艺过程的影响。