"Accelerated life tests (ALTs) have become an indispensable tool for reliability engineers to quantify a product’s reliability, and for product managers to make product release decisions. However, there are many common misuses of ALTs and misinterpretations of their results. This book provides a framework for the proper design and analysis of ALTs. It compares ALTs with other industrial testing experiments, and provides guidance on their appropriate application. It features lots of examples using real data from industrial experiments, and provides statistical software for their implementation. It can be used as a textbook for students of reliability, or as a reference for practitioners"--Provided by publisher.
Provides authoritative guidance on statistical analysis techniques and inferential methods for one-shot device life-testing Estimating the reliability of one-shot devices—electro-expolsive devices, fire extinguishers, automobile airbags, and other units that perform their function only once—poses unique analytical challenges to conventional approaches. Due to how one-shot devices are censored, their precise failure times cannot be obtained from testing. The condition of a one-shot device can only be recorded at a specific inspection time, resulting in a lack of lifetime data collected in life-tests. Accelerated Life Testing of One-shot Devices: Data Collection and Analysis addresses the fundamental issues of statistical modeling based on data collected from accelerated life-tests of one-shot devices. The authors provide inferential methods and procedures for planning accelerated life-tests, and describe advanced statistical techniques to help reliability practitioners overcome estimation problems in the real world. Topics covered include likelihood inference, competing-risks models, one-shot devices with dependent components, model selection, and more. Enabling readers to apply the techniques to their own lifetime data and arrive at the most accurate inference possible, this practical resource: Provides expert guidance on comprehensive data analysis of one-shot devices under accelerated life-tests Discusses how to design experiments for data collection from efficient accelerated life-tests while conforming to budget constraints Helps readers develops optimal designs for constant-stress and step-stress accelerated life-tests, mainstream life-tests commonly used in reliability practice Includes R code in each chapter for readers to use in their own analyses of one-shot device testing data Features numerous case studies and practical examples throughout Highlights important issues, problems, and future research directions in reliability theory and practice Accelerated Life Testing of One-shot Devices: Data Collection and Analysis is essential reading for graduate students, researchers, and engineers working on accelerated life testing data analysis.
The Wiley-Interscience Paperback Series consists of selected books that have been made more accessible to consumers in an effort to increase global appeal and general circulation. With these new unabridged softcover volumes, Wiley hopes to extend the lives of these works by making them available to future generations of statisticians, mathematicians, and scientists. ". . . a goldmine of knowledge on accelerated life testing principles and practices . . . one of the very few capable of advancing the science of reliability. It definitely belongs in every bookshelf on engineering." –Dev G. Raheja, Quality and Reliability Engineering International ". . . an impressive book. The width and number of topics covered, the practical data sets included, the obvious knowledge and understanding of the author and the extent of published materials reviewed combine to ensure that this will be a book used frequently." –Journal of the Royal Statistical Society A benchmark text in the field, Accelerated Testing: Statistical Models, Test Plans, and Data Analysis offers engineers, scientists, and statisticians a reliable resource on the effective use of accelerated life testing to measure and improve product reliability. From simple data plots to advanced computer programs, the text features a wealth of practical applications and a clear, readable style that makes even complicated physical and statistical concepts uniquely accessible. A detailed index adds to its value as a reference source.
An accelerated life testing problem in which the stress s can take only a fixed, finite number of values is known as accelerated life test with step stress. In general, the item under test is started under the lowest stress first and if an item has not failed until a certain specified time, then it is moved into the next level of stress. This process is continued until the item fails. Thus the life test duration of the item is shortened. A Bayesian formulation of the problem is given in this paper. It is assumed that there only two stress values under consideration (1) standard use environmental condition (ii) a higher level of stress that is fixed in advance and is the same for all items to be tested. However, the time at which an item on test is taken out of use environment and put under higher stress environment can be chosen by the experimenter subject to a cost structure. We consider the inference and the optimal design problem of when the change the stress as the test progress. Keywords: Accelerated life test, Step stress, Optimal design, Bayesian approach.
This compact and easy-to-understand text presents the underlying principles and practice of reliability engineering and life testing. It describes the various techniques available for reliability analysis and prediction and explains the statistical methods necessary for reliability modelling, analysis and estimation. The text also discusses in detail the concepts of life testing, its classification and methodologies as well as accelerated life tests, the methodologies and models of stress related failure rates evaluation, and data analysis. Besides, it elaborates on the principles, methods and equipment of highly accelerated life testing and highly accelerated stress screening. Finally, the book concludes with a discussion on the parametric as well as non-parametric methods generally used for reliability estimation, and the recent developments in life testing of engineering components. Key Features The book is up-to-date and very much relevant to the present industrial, research, design, and development scenarios. Provides adequate tools to predict the system reliability at the design stage, to plan and conduct life testing on the products at various stages of development, and to use the life test and field data to estimate the product reliability. Gives sufficiently large number of worked-out examples. Primarily intended as a textbook for the postgraduate students of engineering (M.Tech., Reliability Engineering), the book would also be quite useful for reliability practitioners, professional engineers, and researchers.
Accelerated Testing and Validation Methods is a cross-disciplinary guide that describes testing and validation tools and techniques throughout the product development process. Alex Porter not only focuses on what information is needed but also on what tools can produce the information in a timely manner. From the information provided, engineers and managers can determine what data is needed from a test and validation program and then how to select the best, most effective methods for obtaining the data.This book integrates testing and validation methods with a business perspective so readers can understand when, where, and how such methods can be economically justified. Testing and validation is about generating key information at the correct time so that sound business and engineering decisions can be made. Rather than simply describing various testing and validation techniques, the author offers readers guidance on how to select the best tools for a particular need, explains the appropriateness of different techniques to various situations and shows how to deploy them to ensure the desired information is accurately gathered. Emphasizes developing a strategy for testing and validation Teaches how to design a testing and validation program that deliver information in a timely and cost-effective manner
Today's manufacturers are under tremendous pressure to develop new technological and high reliability products in record time. This has motivated reliability engineers to evaluate the reliabilities of such products. Reliability testing under accelerated environment — accelerated life testing helps to meet this challenge.This comprehensive and must-have edition provides a broad coverage of the optimal design of Accelerated Life Test Plans under time-varying stress loadings. It also focuses on the formulation of Accelerated Life Test Sampling Plans (ALTSPs) which integrate accelerated life tests with quality control technique of acceptance sampling plans. These plans help to determine optimal experimental variables such as appropriate stress levels, optimal allocation at each stress levels, stress change points, etc, depending on the stress loading scheme. ALTSPs determine optimal plans such that the producers' and consumers' risks are safeguarded.
The accelerated life testing is used to quickly demonstrate the ability of a product to perform its role, by increasing the stress conditions compared to those of its operational life. This educational book on the implementation of accelerated life testing therefore explains its theoretical foundations and offers a practical application guide which covers state-of-the-art thinking on design techniques and optimal planning of tests.
Accelerated testing (most types of laboratory testing, proving ground testing, intensive field/flight testing, any experimental research) is increasingly a key component for predicting of product’s/process performance. Trends in Development Accelerated Testing for Automotive and Aerospace Engineering provides a completely updated analysis of the current status of accelerated testing, including the basic general directions of testing (methods and equipment) development, how one needs to study real world conditions for their accurate simulation and successful accelerated testing, describes in details the role of accurate simulation in the development of automotive and aerospace engineering, shows that failures are most often found in the interconnections, step-by-step instructions and examples. This is the only book presently available that considers in detail both the positive and negative trends in testing development for prediction quality, reliability, safety, durability, maintainability, supportability, profit, and decreasing life-cycle cost, recalls, complaints and other performance components of the product. The author presents new ideas and offers a unique strategic approach to obtaining solutions which were not possible using earlier. His methodology has been widely implemented, continue to be adopted throughout the world, and leads to advance society through product improvement that can reduce loss of life, injuries, financial losses, and product recalls. It also covers new ideas in development positive and cost- effective trends in testing development, especially accelerated reliability and durability testing (ART/ADT), which includes integration accurate simulation of field/flight influences, safety, human factors, and leads to successful prediction of product performance during pre-design, design, manufacturing, and usage for the product’s service life. Engineers, researchers, teachers and postgraduate/advanced students who are involved in automotive and aerospace engineering will find this a useful reference on how to apply the accelerated testing method to solve practical problems in these areas. Explains the similarities and differences between accelerated testing technologies used in automotive, aerospace, and other engineering fields Provides a step-by-step guide for the accurate physical simulation of field conditions for test subjects Includes case studies of accelerated testing in automotive and aerospace engineering
The application of accelerated testing theory is a difficult proposition, yet one that can result in considerable time and cost savings, as well as increasing a product's useful life. In Accelerated Testing: A Practitioner's Guide to Accelerated and Reliability Testing, readers are exposed to the latest, most practical knowledge available in this dynamic and important discipline. Authors Bryan Dodson and Harry Schwab draw on their considerable experience in the field to present comprehensive, insightful views in this book. Development and quality assurance tests are defined in detail and are presented from a practical viewpoint. Included are testing fundamentals, plans and models, and equipment and methods most commonly used in accelerated testing. Individuals seeking to evaluate and improve the design lives of components and systems will find this book a valuable reference, with special attention being paid to testing in the mobility industries.
