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581.
针对传统轮换方法在战储器材轮换上的缺陷和不足,结合长储器材失效数据较少、无法实时检测等特点,提出了一种利用定期检测数据分析小子样储存可靠度,并估计其储存寿命来确定轮换期的方法。在求解寿命分布参数时,为克服迭代法运算时间较长、初始值选取对迭代结果收敛性影响较大等不足,利用粒子群算法求解。通过实例分析表明,该方法得到的结果与工程实际相吻合,能为战储器材的轮换提供有效的决策支持。  相似文献   
582.
国内耦合协调度模型的误区及修正   总被引:11,自引:0,他引:11  
随着对科学发展观认识的深入,耦合协调度模型成为研究区域整体均衡发展程度的有效评价与研究工具。但在该模型使用中,存在书写错误、丢失系数、错用权重和模型不成立四类误区,已经显著影响到学术研究的科学性。因此首先明确传统耦合协调度模型的规范公式,在探讨该传统模型在社会科学领域研究中效度问题基础上,进一步提出耦合度的修正模型。此外耦合协调度模型还存在指标构建的主观性、耦合结果的波动性和无可比性的信度问题。以京津冀生态与经济系统为例,验证修正后的耦合协调度模型具有较好的效度,研究对象的时空变化会显著影响耦合协调度模型的信度。  相似文献   
583.
介绍了新型弹药和加速试验的相关理论,并分析了加速试验在新型弹药方面研究的国内外现状.对新型弹药全寿命周期各阶段进行了划分,概述了加速试验在不同阶段的应用状况.区分了加速寿命试验和加速退化试验两种类型,对加速试验数据的处理流程进行了阐述.分别对寿命分布模型、加速模型及参数估计三个内容进行了简要概括,指出了常见模型的种类、假设检验和参数估计的一般方法.最后指出了加速试验的现状及下一步的研究方向.  相似文献   
584.
航空电子设备加速可靠性试验有限元分析应用进展   总被引:1,自引:0,他引:1       下载免费PDF全文
通过综述有限元分析在加速可靠性试验中的最新应用成果,分析了航空电子设备加速可靠性试验技术的基本现状和存在的挑战.主要从航空电子设备可靠性试验现状、有限元理论基本概念和应用方法以及有限元在电子设备可靠性试验的工程运用现状等方面进行了综述分析.首先对有限元理论的基本概念、原理和主要应用方法进行了阐述.其次,结合有限元分析在航空电子设备加速可靠性试验的应用研究现状,总结了其优缺点.研究发现,有限元分析能较好地解决航空电子设备加速可靠性试验中试验成本高、操作复杂的问题,可以较好地完成对加速可靠性试验的仿真模拟.最后对有限元分析应用于航空电子设备加速可靠性试验的研究方向进行了展望,提出了将有限元分析与传统可靠性理论相结合的几点研究思路,为未来航空电子设备加速可靠性试验方法提供整体发展思路与建议.  相似文献   
585.
针对诱发滑油温度传感器故障模式的主要环境因素进行了分析,确定了影响滑油温度传感器可靠性的敏感环境应力。根据滑油温度传感器结构间的逻辑关系和可靠性框图,建立其故障树,找出了潜在薄弱环节作为可靠性强化试验的主要关注点。依据可靠性强化试验理论设计了试验方案,并制定了试验剖面。  相似文献   
586.
Automatic process control and control room operators supervision/intervention in an emergency are of critical importance in major hazard industries. These combined operator and automatic actions are defined in Detailed Action Plans (DAP). A framework has been proposed for analyzing the reliability, and hence the likelihood of success, of DAPs. The Reliability Block Diagram technique is utilized for modeling the reliability of integrated automatic-operator emergency actions. The focus is on incorporating operator's operational and cognitive errors in the process/equipment reliability analysis. For this purpose, the human reliability analysis method SPAR-H is utilized. The proposed framework was used for analyzing emergency response DAPs of a real process plant in order to check and improve its applicability. It is argued that the presented framework facilitates the DAP assessment process by performing Task Analysis, modeling the detailed tasks as well as reliability analysis, thereby uncovering the shortcomings of the designed DAPs. Besides, it provides a very effective, transparent tool with insight into improvement areas and directions for improving the reliability of DAPs.  相似文献   
587.
This article addresses methodological issues of the human reliability analysis (HRA) in the context of probabilistic safety studies. Several conventional HRA techniques, more often used for the evaluation of the human error probabilities (HEPs), have been classified. A taxonomy of human actions, failure events, and related factors is outlined in order to distinguish action phases, human behavior types and incorrect outputs (errors of omission or commission), error types (slips, lapses, and mistakes), and performance-shaping factors (PSFs) influencing the human performance. A tree is proposed to facilitate the selection of a specific method for the evaluation of human reliability with regard to attributes of the situation analyzed. A software system based on the expert system technology to facilitate and document PSA and HRA is outlined. At the end of the article some research challenges in the domain are discussed.  相似文献   
588.
This article presents the results of an evaluation and comparison study of three subjective techniques for determining human reliability under stress for work performed at two Taiwanese security companies. Stress levels at security companies were estimated by using the Unified Tri-service Cognitive Performance Assessment Battery and 40 participants from two similar-sized companies. Experiment results (memory searching task and mathematical processing task) indicated that the participants were under high levels of stress. Three subjective techniques (Success Likelihood Index Method, Technique for Human Error Rate Prediction, and Human Error Assessment and Reduction Technique) for estimating human error probability were evaluated and compared by using 20 experts for six tasks. The comparison criteria are interjudge consistency and accuracy. Of the three human error probability tests studied, the Technique for Human Error Rate Prediction and Success Likelihood Index Method were more consistent than the Human Error Assessment and Reduction Technique. The same relationship occurred in the comparison of accuracy. Thus, the Human Error Assessment and Reduction Technique may need to be modified in some way if it is to be useful. It was already known that this technique required modifications in error-producing conditions and nominal human unreliability. Our work presents additional evidence to substantiate this.  相似文献   
589.
Background. The purpose was to study the test-retest reliability and internal consistency of questions in aquestionnaire concerning working conditions and health and the inter-rater reliability of observations andmeasurements according to an ergonomic checklist. Method. Fifty-seven operators participated in a retestquestionnaire and 58 operators participated in an inter-observer test. Results. The questions had fair to good or higher reliability in 142 of the total of 312. Twenty-seven of the total of 44 variables in the ergonomicchecklist were classified as having fair to good or higher reliability. Conclusions. About half of the questionshad fair to good or higher reliability and can be recommended for further analyses. The majority of variablesin the ergonomic checklist were classified as having fair to good or higher reliability. Low reliability does notnecessarily indicate that the reliability of the test, per se, is low but may signify that the conditions measuredvary over time or that the answers are aggregated in one part of the scale.  相似文献   
590.
为有效预测船舶引航员作业中的安全可靠性,预防引航事故,基于其职业特点,提出了情绪状态、注意力、心情状态等动态和静态评价指标各5个,并采用专家评价或自评的方式对指标赋值。采用专家调查、DEMATEL方法,研究、验证了指标的合适性和指标间关系的正确性,并确定了各指标的权重。结果表明:引航员心情状态的权重最大(0.123 6),基本生理素质的权重最小(0.082 6);最后通过案例分析,得到某一级引航员的可靠性值为91.342 5。引航员在工作中有良好的心理和生理状态以及良好的操作技能,有助于引航员可靠性的提高,从而减少引航事故的发生。  相似文献   
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