			Home About us Contact

Reliability Prediction (reliability + prediction)

Distribution by Scientific Domains

Engineering	83%

Selected Abstracts

Field Reliability Prediction in Consumer Electronics Using Warranty Data

QUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 4 2007
Roxana A. Ion
Abstract In innovative fast product development processes, such as consumer electronics, it is necessary to check as quickly as possible, using field data, whether the product reliability is at the right level. In consumer electronics, some major companies use the Warranty Call Rate (WCR) for this purpose. This paper discusses extensively the theoretical and practical drawbacks of the WCR. Subsequently, it is demonstrated, using a Weibull failure distribution, that only a few months after product launch, say three months, the warranty data offer the opportunity to estimate the parameters of the failure distribution. Of course, this requires that the warranty data are available in the quality department. Unfortunately, for some companies the field feedback information process from the repair centres to the quality department causes a delay of several months. These companies have to speed up their field feedback information process before they can fully take advantage of the proposed estimation procedure. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Long-term Reliability Prediction of 935 nm LEDs Using Failure Laws and Low Acceleration Factor Ageing Tests

QUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 6 2005
Y. Deshayes
Abstract Numerous papers have already reported various results on electrical and optical performances of GaAs-based materials for optoelectronic applications. Other papers have proposed some methodologies for a classical estimation of reliability of GaAs compounds using life testing methods on a few thousand samples over 10,000 hours of testing. In contrast, fewer papers have studied the complete relation between degradation laws in relation to failure mechanisms and the estimation of lifetime distribution using accelerated ageing tests considering a short test duration, low acceleration factor and analytical extrapolation. In this paper, we report the results for commercial InGaAs/GaAs 935 nm packaged light emitting diodes (LEDs) using electrical and optical measurements versus ageing time. Cumulative failure distributions are calculated using degradation laws and process distribution data of optical power. A complete methodology is described proposing an accurate reliability model from experimental determination of the failure mechanisms (defect diffusion) for this technology. Electrical and optical characterizations are used with temperature dependence, short-duration accelerated tests (less than 1500 h) with an increase in bias current (up to 50%), a small number of samples (less than 20) and weak acceleration factors (up to 240). Copyright © 2005 John Wiley & Sons, Ltd. [source]

III-V concentrator solar cell reliability prediction based on quantitative LED reliability data,

PROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 6 2007
Manuel Vázquez
Abstract III-V Multi Junction (MJ) solar cells based on Light Emitting Diode (LED) technology have been proposed and developed in recent years as a way of producing cost-competitive photovoltaic electricity. As LEDs are similar to solar cells in terms of material, size and power, it is possible to take advantage of the huge technological experience accumulated in the former and apply it to the latter. This paper analyses the most important parameters that affect the operational lifetime of the device (crystalline quality, temperature, current density, humidity and photodegradation), taking into account experience on the reliability of LEDs. Most of these parameters are less stressed for a III-V MJ solar cell working at 1000 suns than for a high-power LED. From this analysis, some recommendations are extracted for improving the long-term reliability of the solar cells. Compared to high-power LEDs based on compound semiconductors, it is possible to achieve operational lifetimes higher than 105,hours (34 years of real-time operation) for III-V high-concentration solar cells. Copyright © 2007 John Wiley & Sons, Ltd. [source]

A Computer Implementation of the Separate Maintenance Model for Complex-system Reliability

QUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 7 2006
M. Tortorella
Abstract Reliability modeling and quantitative reliability prediction for all but the simplest system architectures demands intensive computer support for the numerical computations required. Many commercial and academic reliability modeling software packages provide support for the Markov-chain state diagram system reliability model. Other system reliability models, such as those offering non-exponential life and/or repair time distributions, transient analysis, or other special handling, may sometimes be desirable. Users have fewer choices for software supporting these options. This paper describes SUPER, a software package developed at Bell Laboratories, which provides computational support for the separate maintenance model as well as for some other useful system reliability descriptions. SUPER is an acronym for System Used for Prediction and Evaluation of Reliability. The paper also includes a brief tutorial to assist practitioners with system reliability model selection, a review of the models contained in SUPER and their theoretical bases, and implementation issues. SUPER has been used in the telecommunications industry for over 15 years. The paper includes an example from this experience. Copyright © 2005 John Wiley & Sons, Ltd. [source]

The Needs and Benefits of Applying Textual Data Mining within the Product Development Process

QUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 1 2004
Rakesh Menon
Abstract As a result of the growing competition in recent years, new trends such as increased product complexity, changing customer requirements and shortening development time have emerged within the product development process (PDP). These trends have added more challenges to the already-difficult task of quality and reliability prediction and improvement. They have given rise to an increase in the number of unexpected events in the PDP. Traditional tools are only partially adequate to cover these unexpected events. As such, new tools are being sought to complement traditional ones. This paper investigates the use of one such tool, textual data mining for the purpose of quality and reliability improvement. The motivation for this paper stems from the need to handle ,loosely structured textual data' within the product development process. Thus far, most of the studies on data mining within the PDP have focused on numerical databases. In this paper, the need for the study of textual databases is established. Possible areas within a generic PDP for consumer and professional products, where textual data mining could be employed are highlighted. In addition, successful implementations of textual data mining within two large multi-national companies are presented. Copyright © 2003 John Wiley & Sons, Ltd. [source]

Network reliability assessment in a random environment

NAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 6 2003
S. Özekici
Abstract In this paper we consider networks that consist of components operating under a randomly changing common environment. Our work is motivated by power system networks that are subject to fluctuating weather conditions over time that affect the performance of the network. We develop a general setup for any network that is subject to such environment and present results for network reliability assessment under two repair scenarios. We also present Bayesian analysis of network failure data and illustrate how reliability predictions can be obtained for the network. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 574,591, 2003 [source]