大型电子系统紧缩试验方法研究

通过对大型电子系统的抽样原理,紧缩试验方法,可靠性指标计算方法的研究,提出一种新型的基于大型电子系统小型化抽样试验的紧缩系统试验方法,采用最小二乘估计法中的多元回归分析法,得出紧缩系统与大型系统的性能、可靠性指标相关性。经验证试验证明,该试验方法是解决大型电子系统的可靠性验证试验的有效方法。     

航天器产品可靠性指标验证方法探究

对于受到多方条件限制的航天器产品而言,在交付验收阶段和型号出厂前,需要开展可靠性验证工作.航天器产品可靠性定量要求(指标)的验证可以选用多种方法进行.结合光学载荷产品可靠性指标验证的工作经验,提出了一种充分利用产品寿命周期各阶段的可靠性信息,采用贝叶斯法进行可靠性评估的方法.试验证明,这是一种经济、有效和可行的方法.     

可靠性工程与环境工程

0625783基于研制数据的产品可靠性验证方案的确定〔刊,中〕/蒋同斌//淮阴工学院学报.—2006,15(3).—10-12(L)常用抽样检验的方法进行产品可靠性验证,根据这一方法所确定的验证试验方案,在一定的风险下所需样本量较大,有时在工程上是不可接受的。针对这一问题,提出利用产品研制期间的试验数据,重新确定抽样方案,从而减少验证试验所需样本量或降低风险。参130625784基于PROFIBUS的双边剪控制系统的可靠性设计〔刊,中〕/魏伟//计算机测量与控制.—2006,14(7).—912-914(C)0625785合格评定(下)〔刊,中〕/谭福有//信息技术与标准化.—2006,(…     

微波组件硅铝丝键合工艺参数的优化

通过控制单一变量的试验方法,研究了超声功率、超声时间、键合压力等参数对硅铝丝键合一致性和可靠性的影响,分析了每个参数对硅铝丝键合的影响规律.通过正交试验方法,优化了键合参数组合,并进行试验验证.通过环境试验对微波组件中硅铝丝键合的可靠性进行评价,在某产品上进行验证,并抽样对其可靠性进行评价.产品键合点形貌良好,一致性高...     

验证复杂电子系统任务可靠度的试验方案

阐述了基本可靠性验证试验不能取代任务可靠度验证试验的方案。在很多情况下,系统的基本可靠性验证试验获得通过,但任务可靠性却达不到指标要求;相反,任务可靠性验证试验则可以包含基本可靠性的信息。介绍了同时进行两种验证试验的试验方法和数据处理方法。     

可靠性指标增长验证统计方案设计方法

在验收试验之前,在产品的研制过程中往往已有不少对产品的其他信息,比如产品各个阶段的试验信息;在产品的研制过程中,可靠性通常是增长的,因此这类数据符合可靠性增长指标要求。在设计可靠性指标验证方案时．充分地考虑了可靠性增长的信息,基于单调约束模型和Bogey试验设计方法,通过蒙特卡洛算法,给出一种可靠性增长验证统计方案的设计方法。     

一种经济准确的电子装备可靠性评估方法

给出了一种低成本、高准确性的电子装备可靠性评估方法。该方法利用日常工作中积累的电子装备调试、生产、试验和使用过程中的有效可靠性数据,采用合适的可靠性评估数学模型,计算出较准确的电子装备可靠性评估值。收集足够有效的可靠性数据及选择合适的评估模型,是该估计方法的关键。将可靠性验证与装备日常试制、试验工作相结合的可靠性评估方法,属国内首创;同时,该方法适用性强、准确度高而且成本低,具有普遍推广的意义。     

一般性问题

TN061 2003010001机电产品寿命与可靠性综合验证试验技术研究/龚庆祥,王自力(北京航空航天大学)11航空学报一2 002,23(4)一349一352大量机电产品既有可靠性指标要求,又有寿命指标要求,且在研制阶段结束时,需通过试验给出两种指标的验证结果.在对寿命与可靠性综合验证试验的可行性研究的基础上,提出了对其可靠性与寿命指标同时进行综合验证的试验方案.主要介绍该试验方案中的关键内容:试验时间、失效(故障)判据、试验接收与拒收的判决准则的确定、试验结果的评估方法等.该试验方案的应用,为部分机电产品的寿命与可靠性试验验证提供了一个合…     

质量管理人员的基本功以及思考

1质量专业的基本功作为一个质量专业人员,工作的领域很广泛,工厂、供应商、评测、研发等各个环节,在这些管理中,有很多通用的地方是可以总结的:(1)多少要懂得一些抽样理论和可靠性理论,如GB-2828/2829,进行可靠性地抽样和试验的设     

电子设备可靠性试验应力条件的加权方法

电子设备在规定时间内的可靠性水平是与规定的工作、环境条件有关的。测定或验证设备的可靠性指标无疑要对设备施加规定的环境应力。这就在实际工作中提出了两方面的要求:一方面希望缩短可靠性试验时间,设想通过加严试验环境应力条件来达到;另一方面,当不具备对受试设备施加规定的环境应力条件时,希望在现实的环境应力水平下通过加长试验时间来等效。本文试图提出一种综合环境应力和温度应力加权系数,     

Reliability sampling plans for lognormal distribution, based onprogressively-censored samples

This paper presents reliability sampling plans for the lognormal distribution based on progressively censored samples. In constructing these sampling plans, large-sample approximations to the best linear unbiased estimators of the location and scale parameters are used. For some selected progressive censoring schemes, reliability sampling plans are tabulated for p_α and p_β to match MIL-STD-105. While in general, variable-sampling plans require smaller sample size when compared with attribute-sampling plans, the ordinary complete and right-censored life test experiments are special cases of the progressively censored experiment. Hence, the progressively censored reliability sampling plans in this paper are widely applicable. General application of the procedure is discussed, and two examples are provided     

家电产品无故障数据成败型可靠性试验方案探讨

提出以无故障数据为基础的家用电器产品成败型可靠性鉴定试验和验收试验方案,以无故障数据结果来确定试验样品的基数,判定条件为Ac=1,Rc=2,分2小批进行试验,当第1小批结果为无故障数据时,提前结柬实验.从而简化试验方案,减少试验样品数量,缩短试验时间,改善可靠性试验的可操作性和经济性.     

Statistical simulation methods for investigating the structure ofreliability optimization

Qualitative and quantitative techniques for reliability sampling plants are described. An example shows how to apply the techniques to detect service life and the effectiveness of reliability. The relationships between sample size, confidence limits number of failed units during the test, and the fraction of reliable units is shown. By statistical simulation, 55 practical sampling plans were developed. The statistical simulation, with the aid of finite differences and computer analysis, provided a good solution of the authors' research problems. The distribution of the data corresponds rather accurately to the given curves, which are the inverses of the functions of the theoretical distribution based on the formalised approach     

Estimating Reliability Growth

Test programs are conducted to identify system failure modes and to estimate reliability. If the system can be changed so that some of the identified failure modes are eliminated and new failure modes are not introduced, the reliability of the system is improved. This paper examines small-sample techniques for estimating the change in reliability without the benefit of test data from the improved system. A decision to make the improvements can be based on the estimated increase in reliability. The procedures used for estimating changes can also be adapted to estimating reliability using data from a test program conducted in stages. For this case, a sample is taken at each stage and changes are made so that all newly identified failure modes which are correctable are eliminated from the system. Simulation is used to study reliability estimators both when just one sample is taken and when sampling is conducted in stages.     

Limited failure-censored life test for the Weibull distribution

When the distribution of lifetimes is 2-parameter exponential, Balasooriya (1995) provided a failure-censored reliability sampling plan to save test time. This paper extends the Balasooriya sampling plan to the Weibull distribution and provides a limited failure-censored reliability sampling plan (LFCR) to do life testing when test facilities are scarce. The s-expected test time of the LFCR is computed, and the optimal stopping rule of LFCR corresponding to the shortest test time is established. The s-confidence intervals for the parameters are generated     

Reliability screening through electrical testing for press-fit alternator power diode in automotive application

Reliability of individual power diode in automotive electronic systems is crucial. However, present reliability test can be performed only on sampling basis due to its destructiveness. On the other hand, present ΔV_F test cannot fully screen out the weak reliability power diode.In this work, the root cause of the thermal/power cycle reliability test of power diode is identified, and a new electrical screening test is proposed. This test is non-destructive, and it combines the ΔV_F test and the new series resistance test. The series resistance test takes less than 10 ms for each diode, making it possible for 100% screening.Experimental results show that this new screening test can indeed screen out the weak reliability diode effectively and improve its reliability by more than 10 folds.     

机载预警雷达试飞方法的研究

利用计算机模拟或者雷达实际试验飞行时,都会遇到应该试验多少个点的问题.在计算雷达试飞采样点数时,将采样点数的计算从发现概率的统计可信度转换到探测距离的统计可信度,计算出在置信度90％下,置信区间、发现概率和采样点数之间的关系.在此基础上,依据相关国军标中距离采样间隔的计算公式,探讨了机载预警雷达工作在不同模式下距离采样间隔该如何选取,并给出了相关的仿真实验结果.该研究对今后雷达取样有指导作用.     

Effect of local stir and spatial averaging on measurement andtesting in mode-tuned and mode-stirred reverberation chambers

The effect of local averaging in mode-tuned and mode-stirred reverberation chambers is investigated, under the assumption of a wide-sense stationary statistical cavity field. The analysis is based on the characterization of the tuning or stirring process in the spectral spatial domain and in the spectral stir domain. The variance function, scale of fluctuation, optimum sampling rate, and normalized spectral bandwidths are computed for each case, based on the modeled power spectral-density function. This second-order analysis enables the effect of local averaging on the point-interval correlation, mean and standard deviation of the maximum test level, upward threshold crossing frequency, time to first passage and mean excursion length to be quantified. The theoretical results for quantifying EUT reliability are illustrated and compared with measured data. The results provide guidelines for the maximum tolerable sensor aperture and stirrer step sizes for mode tuning, and sampling rate and sampling width for mode stirring in chamber calibration and EMC emissions and susceptibility testing     

A fast Monte Carlo method for evaluating reliability indexes

This paper presents a fast Monte Carlo method, based on importance sampling (IS) distribution, for estimation of reliability indexes in hydroelectric systems. More precisely, it considers the case where the IS distribution comes from the same parametric family as the original (true) one and proposes a simulation-based optimization algorithm for selecting the parameters of the IS in an optimal way. The superiority of this method, relative to the usual Monte Carlo one, is shown for the well-known test problem: IEEE Reliability Test System