Strategic maintenance-management in Nigerian industries

A developing society needs to adapt to change and foster creativity. In the pursuit of continual improvement (e.g., reducing fossil-fuel consumption and waste, better service performance, greater availability and improved reliability), implementing wise maintenance-schedules is essential for contemporary organisations. Several studies of a wide range of Nigerian industries indicate that indigenous low availability and low productivity are endemic. The resulting closure of some of these industries has triggered off a realisation of the strategic challenges in maintenance management. In addition, the increasingly-competitive business environment in Nigeria has raised the strategic importance of maintenance functions, especially in organisations with significant investments in physical assets. Five strategic aspects of maintenance management have been identified, namely: maintenance methodology; support processes; organisation and work structuring; comparable culture; and general management policy. Three factors that permeate these dimensions are wise leadership, excellent communications and an understanding of the human factors involved.     

智能型,交互式目标规划模型决策系统的研究

在分析目标规划模型的基础上,本文建造了企业经营环境 ES 及一个优先级排列ES.文中实现了将模型的定量计算与 ES 的定性推理有机结合,构成—个智能型、交互式、集成化即具有(?)特征的目标规划模型决策系统.该系统已被用于企业经营决策和计划编制中.     

基于软件无线电平台的1090ES扩容信号收发处理

随着空中交通的信息传输与新应用拓展需求不断增加,1090ES信号容量有限问题日益显现,对1090ES信号进行容量扩充是一种有效解决途径。针对一种基于脉内调相的1090ES信号扩容技术,给出了叠加调制的信号模型,研究了1090ES信号的解调解码算法;在GNU Radio+USRP软件无线电平台上,实现了1090ES扩容信号的产生和接收处理,包括脉冲位置调制(Pulse Position Modulation,PPM)与8PSK叠加调制、低通滤波、报头检测、载波同步、PPM解码和相位解调等,并利用Matlab对实验的解码错误率和信号的频谱特性做了统计分析与仿真,结果表明了该扩容技术的可行性。     

普通Petri网最大可达数的两段式死锁控制策略

针对普通Petri网的死锁问题,本文提出了可实现最大可达数的两段式死锁控制策略(deadlock control policy,DCP).第1步,该策略求解原网(N0,M0)的基本信标(elementary siphons,ES)和从属信标(dependent siphons,DS),对每个基本信标添加控制库所(control place,CP)和控制变迁(control transition,CT),获得拓展网系统(N′,M′).第2步,构建拓展网系统的P–不变式整数规划问题,测试原网中从属信标的可控性.若所有从属信标满足可控条件,则直接得到活性受控网系统(N*,M*);反之,对不满足可控条件的从属信标也添加控制库所和变迁,从而也得到了(N*,M*).通过理论分析和算例验证,表明了该死锁控制策略的正确性和有效性.相比目前文献中的可实现最大许可行为数目(number of maximally permissive behavior,NMPB)的普通Petri网死锁预防策略,该DCP获取的活性受控网系统(N*,M*)可达数目与原网(N0,M0)是相同的,且最大可达数(maximally reachable number,MRN)高于最大许可行为数目NMPB.     

ES与GIS一体化在公路生态景观评价及恢复系统中的应用

通过对专家系统（ES）与地理信息系统（GIS）一体化现状、内容、形式等的分析,阐述其一体化中存在的问题,提出解决这些问题的方法,并将ES与GIS一体化应用到公路生态景观评价及恢复系统中。该系统实现过程：建立公路两侧自然本底数据、空间矢量数据、评价指标网子等为主体的数据库;同时建立由专家知识及经验构成的知识库;用相关的评价模型建立模型库和决策库;实现多库统一的地理信息系统与专家系统相结合的决策支持专家系统,实现对公路自身和周嗣景观的多样性评价,同时对不和谐的评价结果提出相应的恢复方案和措施。     

移动设备上大型三维医学体数据的可视化方法

基于OpenGLES2．0平台,针对移动设备的硬件局限性,文中提出了一种新颖的大型三维体数据模型渲染技术,可以克服这些限制,实现在这些平台上以精细的高分辨率绘制大型三维医学体数据模型。另外,提出了一种软件架构,这种架构使现有的体绘制技术可以更好地应用于移动设备。通过采用不同的体数据模型,以逐渐提高分辨率的方式进行了一组实验,结果证明文中的方法是可行的、健壮的,在性能受限的平台上实现了大型体数据模型的可视化。     

Educating reflective Enterprise Systems practitioners: a design research study of the iterative building of a teaching framework

This research paper reports on the iterative design of a teaching framework developed for teaching Enterprise Systems (ES) classes for Information Systems (IS) graduates. These systems embed technical complexity and create organizational challenges when implemented in organizations. Therefore, teaching good ES classes is pedagogically challenging for faculty, and ES curricula are difficult for students. We have gradually designed and rebuilt curricula and teaching frameworks over 8 years. This has also resulted in a set of eight design principles. We report from our design and evaluation process and present our final artefact, the teaching framework. The aim is to educate reflective practitioners with multiple ES skills, enabling them to tackle the complexities of ES implementation contexts. The framework has implications for IS educational research and practice and has some generic values that are transferable to other academic institutions and adaptable to other IS learning environments. Further, the study contributes to IS design research by extending its application area. The ES teaching framework is a specific contribution to IS teaching frameworks as a class of problems.     

ORACLE视图设计方法及应用

结合开发媒电厂管理信息系统的实际经验，讨论ＯＲＡＣＬＥＲＤＢＭＳ视图在网络安全管理，数据交流及数据统计，查询等方面的设计方法和应用技术。     

6SE70矢量控制变频器在高炉上料主卷扬系统中的应用

本文介绍高炉上料主卷扬机（包括机械和电气系统）的构成,着重描述了卷扬机传动变频器的选型和应用参数设置。高炉上料主卷扬电气系统将西门子PLC系统与基于6ES70矢量控制变频器的电气传动系统紧密结合在一起,实现对高炉上料主卷扬机的加料过程控制,提高了卷扬上料系统的稳定性,降低了故障率。该系统已成为高炉实现稳产和高产的装备基础。     

OpenGL ES图形标准在嵌入式系统中的应用

嵌入式系统应用领域越来越广阔,从工业控制、信息家电、个人数字助理到通信娱乐等对图形界面提出了较高的要求.介绍了新一代嵌入式系统图形开发标准OpenGL ES发展背景和发展现状,讨论了基于OpenGL ES的开发过程,开发方法及在嵌入式系统中的应用,经综合比较及分析表明OpenGL ES具有适合性,可移植性以及灵活性等优点.