地铁盾构隧道预制管片施工检验技术

文章主要阐述了西安地铁三号线通化门~胡家庙~石家街盾构区间预制管片施工工法、管片检验、管片质量控制措施等内容,希望能够为盾构混凝土管片生产质量提高起到借鉴作用。     

基于FLAC3D的神华蒙西棋盘井16#煤田回风巷锚杆支护研究

以棋盘井煤矿16#煤层的生产地质资料和9#煤层巷道实际维护效果为依据,采用三维数值模拟软件FLAC3D,结合理论分析和工程实践研究确定16#煤层回风巷合理的支护形式和支护参数。     

试论目前架空输电线路状态运行与维护管理

文章分析目前架空输电线路状态运行与维护管理基本现状,介绍了架空输电线路状态运行与维护管理完善对策,以期提高该架空输电线路状态运行与维护管理整体效率。     

A qualitative study on the exploration of challenges to the implementation of the Safety Management System in aircraft maintenance organizations in Turkey

Safety management has recently started using a paradigm that ‘sees the world as it is’ rather than ‘prescribing how it should be’. The Safety Management System (SMS), a product of this paradigm shift, has fairly new and different characteristics. These changes are expected to pose a number of challenges to the successful implementation of the SMS. This qualitative research study sets out to explore challenges to the implementation of the SMS in aircraft maintenance organizations in Turkey, with reference to the perceptions of Quality Management Systems (QMSs) and SMS experts working at these maintenance organizations.Qualitative data was collected from thirty participants through an open-ended questionnaire. Both inductive and deductive methods were used for the data analysis. The results suggest that the SMS entails a cultural transformation and is likely to bring about certain challenges because of its new and different characteristics. It is concluded that significant challenges may derive from a poor positive safety culture. Top management support and the practices of the civil aviation authority also have the potential to pose challenges. Other challenges are expected to result from SMS training and the need for the integration of stakeholder SMSs.The research results are expected to improve the success of the SMS and hence safety in aircraft maintenance. The results may also encourage the regulatory authorities to take measures to improve the success of the SMS in the launch of State Safety Programs (SSPs).     

Aircraft line maintenance scheduling and optimisation

With the advent of new technologies and more modern aircraft, many of the maintenance jobs traditionally scheduled for periodic block checks can now be performed in the ‘‘line maintenance” environment, i.e., during layovers between scheduled flights of an aircraft. This flexibility can be exploited to reduce maintenance costs and improve fleet utilisation of an airline. In this paper we introduce and study the Line Maintenance Scheduling Problem (LMSP). The LMSP assigns jobs to available maintenance opportunities, defined by aircraft routes, and sets the starting time for each job. Its objective is to minimise the deviation from this schedule with respect to given due dates for each task, without exceeding resource capacity at the airports at any moment. We formulate the LMSP as a mixed integer programming problem, and describe and compare two solution approaches for this problem: an integrated exact solution algorithm, which solves job assignment and timetabling simultaneously, and a sequential, heuristic approach. We tested our algorithms on a set of instances inspired on data provided by an industry partner. Our experiments show the applicability of both approaches on realistic settings: the exact approach was able to find the optimal solution for all instances, in less than 10 min on average. Our analysis also shows with an example that line maintenance can be more efficient when capacity is spatially spread, even if the total capacity is reduced.     

我国家电连锁企业盈利策略探究——以广州市场为例

中国的家电零售业正在向专业化、特色化、网络化、跨区域化迅速发展,本文以我国家电连锁经营企业在一级市场发展的一个典型——广州家电零售市场为例,从主客观角度出发,分析了家电连锁业态的现状、连锁经营模式的瓶颈,提出了家电连锁经营盈利模式趋向及竞争策略。     

水利施工机械维修的有关措施以及建议探讨

施工过程中机械发生了故障就会对工程的进度与质量造成严重的影响,甚至会对正常生产造成严重影响,所以对施工机械进行维修是非常重要的。本文对水利施工机械维修的相关措施进行了探讨,并在此基础上提出了一些有关水利施工机械维修的建议,供大家参考。     

提高架空输电线路运行的安全可靠性与经济性

当前输电线路在运行的安全可靠性与经济性方面面临诸多挑战。本文深入分析了线路运行中的安全可靠性问题与经济性问题。并从加大线路巡视力度、建立在线监测系统、开展状态检修、提高设计能力等四个角度给出了相应的措施与对策。     

煤矿机电设备的维护保养

煤矿机电设备的维护保养是设备管理中的重要环节,是技术人员的主要工作内容之一。一台精心维护的设备可以在较长的时间保持良好的性能,而忽视了维护保养,就会在很短的时间内损坏甚至报废及发生事故,本文主要阐述了煤矿机电设备的维护保养要求和设备维护保养制度等问题。     

基于FMECA方法的无人机航电系统维修决策

本文首先介绍了无人机航电系统的功能结构,然后,分析了对无人机航电系统进行FMECA分析的方法;最后,以舵机实例分析结果为依据,研究分析了航电系统的维修工作内容制定、预防性维修间隔期确定和预防性维修工作组合等FEMCA关键技术。