基于QFD的工程机械维修性设计要求分析

 维修性设计是工程机械研究阶段必须开展的一项重要工程活动,而维修性设计要求的提出与确定又是后续各项维修性工作的前提与基础。简要介绍了质量功能展开(QFD)方法,重点论述了质量屋(HoQ)的基本构成;探讨了基于QFD的工程机械维修性设计要求分析过程,主要包括提出客户维修需求、确定维修需求权重、提出维修性设计指标、构造设计指标关系矩阵、构造设计指标——维修需求关系矩阵和得出维修性设计指标权重矩阵6个步骤。最后,通过运用该方法对某型推土机维修性设计要求进行了分析,得出了其维修性设计指标重要度排序依次为拆装性、模块化、标准化、简易化、可达性和易识别性。结果表明,引入QFD方法对工程机械维修性设计要求进行分析,在分析过程中将定性分析与定量研究有机结合起来,能够解决工程机械维修性设计要求分析过程中的复杂性与不确定性问题,并得出对维修性设计要求的有效评价,具有很高的实用价值。     

某型火箭助飞鱼雷维修性指标验证试验方法研究

维修性指标是某型火箭助飞鱼雷定型试验需要验证的重要指标。本文根据某型火箭助飞鱼雷定型试验的特点,叙述了指标验证的实施方案、方法,依据相关标准、规范,运用现场试验产生的实际故障,在自然故障不足时采用模拟故障补足样本量的方法对维修性指标进行验证和评价,力争准确验证某型火箭助飞鱼雷是否满足规定的维修性要求。     

某船用装备的维修性设计分析与试验验证

维修性是装备重要的通用质量特性之一,良好的维修性既可提高装备的战备完好性和任务成功性,也能有效降低装备的寿命周期费用。该文基于装备维修性相关标准要求,对某船用装备的维修性进行设计,并对其进行了FMECA和RCMA分析。结合船员级可维修更换作业实操情况,进行装备维修性试验验证。该装备的定性、定量试验评定结果表明该设计满足装备的维修性要求。     

虚拟维修技术在民机维修性设计中的应用研究

维修性是民机的重要属性,直接影响民机的设计质量和市场竞争力。虚拟维修技术的发展为民机的维修性设计提供了新的方法。本文对虚拟维修技术在民机维修性设计中的应用进行了初步探索,重点探讨了虚拟维修场景实现、维修过程仿真以及虚拟环境下维修性指标的评估与验证这三个方面的关键问题。     

设备管理中的维修性模型

本文在简略地回顾维修性理论的历史以后,扼要地说明维修性的定义並指出维修特性为对数正态分布的情况下维修度的计算方法。本文用维修策略理论证明设备有维修可以提高任务时间内的可靠度,並定量地给出维修周期与系统平均寿命的关系,且特别指出单个指数元件系统的维修是无效的。此外,根据维修策略推导出事前维修的置换费用的计算公式以及维修费用的计算方法。     

基于多因子融合的维修性验证试验故障样本分配方法研究

针对维修性验证试验中样本分配结果不理想,导致维修性验证试验结论置信度低的问题,提出了基于多因子融合的维修性验证试验样本分配方法;首先,通过对故障样本分配影响因素的分析,定义了故障样本分配影响因子集,提出了基于多因子融合的故障样本分配算法;然后,分别确定了各影响因子的影响系数,并采用模糊层次分析法获得了各影响因子的影响权值;最后,以某型装备子系统为例进行实例验证,并同基于故障率的分层抽样样本分配方法进行对比分析,结果表明该方法得到的样本分配结果结构更加科学,提高了试验结论的置信度,具有良好的工程应用价值。     

基于广义可用性的系统可用性评价

文章介绍了广义可用性分析方法的理论基础和工作流程,并提出了计算可用性指标的含义.本文还描述了可用性指标与安全性指标和维修性指标之间的关系.安全性指标和维修性指标是计算可用性的基础,直接影响可用性指标的计算结果.本文在提出计算方法的同时,以举例形式说明计算方法的可行性.     

基于故障树的无人机发动机点火系统维修性建模

结合无人机发动机点火系统的特点,以故障树为基础,建立了无人机发动机点火系统基于故障树的维修性模型,对其进行定量分析得到点火系统的修复性维修时间.该方法利用可靠性分析的故障树理论,提供了维修过程的基本思想和数据,解决了定量分析维修性数据不足的困难,提高了系统维修效率.     

一种基于AHP的民用飞机某系统维修性评价方法

民用飞机的维修性设计好坏对于提高_飞机性能,节省全寿命维修费用有着非常重要的影响。本文运用了一种定量方法一层次分析法建立了设备维修性评估分析模型,并运用该方法评价了设备的维修性。     

导弹武器系统维修性设计要求

导弹武器系统先天的维修性，直接关系到部队的作战使用与后勤保障。因此，从事武器系统设计、使用及维修人员，都应十分重视其维修性设计。本文针对导弱武器系统的特点，从可达性、可测性、互换性、标准化、人素工程、安全性等诸方面来对维修性设计提出定性要求；讨论了维修性设计定量指标的分配与维修等级的确定。     

电压偏置下考虑了自热效应的非致冷红外测辐射热计响应率的推导

非致冷红外测辐射热计是一种有源器件,工作时器件的自热效应不容忽略。从理论上推导出在电压偏置下考虑了自热效应的非致冷红外测辐射热计响应率的计算公式。     

Software Maintainability Evaluation Based on Quantitive Model

Software maintainability is one of the most important factors of software quality,but it is seriously difficult to evaluate the maintainability. Without evaluation,it is impossible to control. To estimate software maintainability state,parameter system of software was built up and maintainability state was defined into three states.Thought of application on maintainability evaluation based on hidden Markov chain( HMC) and fuzzy inference was presented.Three-state maintainability estimation model was constructed. To testify the feasibility of the model, a real example of software maintenance activity was carried out and the result from the example validated that the results of this study were applicable.     

Softw are Maintainability Evaluation Based on Software Configuration Management Data

As one of the most important attributes of software quality, software maintainability has been widely recognized.However,the existing maintainability evaluation methods are mostly based on subjectively judgment. Thus it is inapplicable or unbelievable. To evaluate software maintainability objectively,the software configuration management( SCM) data are collected to establish a maintainability model. Based on the hidden Markov chain( HMC), a three-state maintainability estimation model is constructed. To validate the feasibility of the model,a real software example of software maintenance activity is given and the result from the example shows the effectiveness of the proposed method.     

基于灰色关联的无人值守变电站维修性评估

分析了模糊评估模型的构建原理,应用模糊映射和灰色关联理论构建了模糊综合评估理论模型,提出了无人值守变电站维修性评估灰色关联度建模和计算方法,给出了220kV无人值守变电站维修性评估实例.结果表明,采用二级分层模型,可以显著降低多因素评估的计算复杂性,高效地实现目标评估.     

Software Maintainability Prediction with UML Class Diagram

Software system can be classified into many function modules from the perspective of user. Unified modeling language( UML) class diagram of each function module was extracted,and design characteristic metrics which influenced software maintainability were selected based on UML class diagram.Choosing metrics of UML class diagram as predictors,and mean maintenance time of function module was regarded as software maintainability parameter. Software maintainability models were built by using back propagation( BP) neural network and radial basis function( RBF) neural network, respectively and were simulated by MATLAB. In order to evaluate the performance of models,the training results were analyzed and compared with leaveone-out cross-validation and model performance evaluation criterion. The result indicated that RBF arithmetic was superior to BP arithmetic in predicting software maintainability.     

基于MVC的手机通讯录设计与实现

MVC模式的设计思想为J2ME平台的手机程序开发提供了有力的支持,具有健壮性、可维护性和可扩展性等优点.讨论了MVC模式在手机通讯录开发中的应用,并说明该模式的优点.     

Electric Multiple Unit Bogie Maintainability Allocation with Interval Analysis and Fuzzy Evaluation Method

Based on the failure rate and design features allocation method,considering the multiple influential factors which affect electric multiple unit（ EMU） bogies,maintainability allocation on EMU bogie was presented by interval analytic hierarchy analysis and fuzzy comprehensive assessment. The maintainability allocation model was established. Weight based on the influence degree of each factor on maintenance was assigned. Fuzzy interval numbers were used to substitute real numbers and express uncertain information.The maintenance weighting factors for each subsystem were calculated by fuzzy comprehensive assessment. Then the allocation method was applied to EMU bogie. The results show that the method is feasible. The problem difficult to quantify for EMU bogie maintenance allocation is solved effectively.