汽车电源系统故障诊断与维修

汽车电器已经成为现代汽车结构中必不可少的一部分,所有的电器系统要工作都必不可少地要有电能的支持,因此汽车电源就居于非常重要的地位。本文着重探讨汽车电源系统的常见故障分析、诊断以及维修作业的主要内容。     

Corporate crisis advertising: A framework examining the use and effects of corporate advertising before and after crises

While corporate advertising has been widely studied as a promotional tool, few studies have examined how it can be used in a corporate crisis situation. In 2013, Kim proposed a conceptual framework for examining stakeholders’ evaluation of pre-crisis corporate advertising, using the inoculation and reactance theory. The framework, published in Journal of Marketing Communications, suggested that pre-crisis advertising can increase audience resistance towards negative news of an organization and decrease audience resistance towards future corporate advertisements from the organization. The present study expands on Kim’s work to develop the corporate crisis advertising (CCA) framework. In addition to the inoculation and reactance effects discussed in Kim’s model, CCA aims to discuss the effects of corporate advertising on improving organization’s prior reputation based on halo effect, and how post-crisis advertising messages can be evaluated based on crisis theories. Our proposed framework provides a comprehensive view of the use of corporate advertising both before and after a crisis and is useful for organizations to understand the impact of corporate advertising on stakeholders’ evaluation of the organization in a crisis situation. Potential applications of CCA are discussed and directions for future research suggested.     

A Canadian cost-effectiveness analysis of transcatheter mitral valve repair with the MitraClip system in high surgical risk patients with significant mitral regurgitation

Objective:

In patients with significant mitral regurgitation (MR) at high risk of mortality and morbidity from mitral valve surgery, transcatheter mitral valve repair with the MitraClip System is associated with a reduction in MR and improved quality-of-life and functional status compared with baseline. The objective was to evaluate the cost-effectiveness of MitraClip therapy compared with standard of care in patients with significant MR at high risk for mitral valve surgery from a Canadian payer perspective.

Methods:

A decision analytic model was developed to estimate the lifetime costs, life years, quality-adjusted life years (QALYs), and incremental cost per life year and QALY gained for patients receiving MitraClip therapy compared with standard of care. Treatment-specific overall survival, risk of clinical events, quality-of-life, and resource utilization were obtained from the Endovascular Valve Edge-to-Edge REpair High Risk Study (EVEREST II HRS). Health utility and unit costs (CAD $2013) were taken from the published literature. Sensitivity analyses were conducted to explore the impact of alternative assumptions and parameter uncertainty on results.

Results:

The base case incremental cost per QALY gained was $23,433. Results were most sensitive to alternative assumptions regarding overall survival, time horizon, and risk of hospitalization for congestive heart failure (CHF). Probabilistic sensitivity analysis showed MitraClip therapy to have a 92% chance of being cost-effective compared with standard of care at a willingness-to-pay threshold of $50,000 per QALY gained.

Study limitations:

Key limitations include the small number of patients included in the EVEREST II HRS which informed the analysis, the limited data available to inform clinical events and disease progression in the concurrent comparator group, and the lack of a comparator group from a randomized control trial.

Conclusion:

MitraClip therapy is likely a cost-effective option for the treatment of patients at high risk for mitral valve surgery with significant MR.     

激光熔覆技术在石化机械维修上的应用

文章结合石油化工生产设备的使用特点,介绍了辽阳石油化纤公司通过开发、应用激光熔覆技术,不断提高石油化工生产设备的完好性、可靠性,指出该技术对解决石油化工生产设备故障的重要意义。     

Simultaneous control of production, repair/replacement and preventive maintenance of deteriorating manufacturing systems

This paper presents a method to find the optimal production, repair/replacement and preventive maintenance policies for a degraded manufacturing system. The system is subject to random machine failures and repairs. The status of the system is deemed to degrade with repair activities. When a failure occurs, the machine is either repaired or replaced, and a replacement action renews the machine, while a repair action brings it to a degraded operational state, with the next repair time increasing as the number of repairs increases as well. A preventive maintenance action is considered in order to improve the reliability of the machine, thereby reducing the amount of disruptions caused by machine failures. The decision variables are the production rate, the preventive maintenance rate and the repair/replacement switching policy upon machine failure. The objective of the study is to find the decision variables that minimize the overall cost, including repair, replacement, preventive maintenance, inventory holding and backlog costs over an infinite planning horizon. The proposed model is based on a semi-Markov decision process, and the stochastic dynamic programming method is used to obtain the optimality conditions. A numerical example is given to illustrate the proposed model, and a sensitivity analysis is considered in order to confirm the structure of the control policy and to illustrate the usefulness of the proposed approach.     

关键维修备件的库存管理刍议

从维修备件库存的概念和作用入手,阐述了关键维修备件库存管理的重要性及库存管理中的难点所在,并从对库存需求合理分类与区别订货、加强企业合作与联合管理、注重企业内部沟通与协作等三个方面对库存管理的策略进行了探究。     

关于提高车辆装备维修保障能力的研究

近年来,军队建设得到了快速发展和提升,高科技的广泛推广和应用在一定程度上也促进了装备维修和保障工作的发展,为了更好地服务于军队建设,车辆装备维修工作也将面临大的挑战和新的要求。如何提高车辆装备维修保障能力成为一项亟需解决的问题。文章就现在车辆装备维修保障工作中存在的问题进行分析,并提出相应对策,以供参考。     

浅析电子天平原理及常见故障调修

电子天平主要以计量检测、传递量值、化验产品以及科学分析等内容,广泛地运用于教育、农业、工业、电子以及科研单位等行业,是一种不可缺少的物质称量仪器。本文就电子天平的工作原理进行了分析,并对其常见的故障进行了研究,讨论了调修方法,对电子天平后期的使用、检测以及维护保养有较大的帮助。     

我国航空电子维修质量体系和安全管理概述

随着民用航空维修技术的发展,对航空电子维修技术人员综合能力的要求也越来越高。在现有民航维修质量体系的要求下,航空电子维修站应如何进行质量改进以最大限度地保证维修部件的持续适航性的问题。本文对此进行一个分析研究。     

关于飞机修理钣铆技术“工学结合”人才培养模式改革的问题与对策

本文通过全面分析了《飞机修理钣铆技术》"工学结合"课程改革中出现的问题和困难,并针对这些问题和困难,从软件和硬件两方面提出了可行的应对对策和解决方法。