Download or read book Prediction of Fatigue Crack Near threshold Censored Regressions with Run out Data written by Yasser Alansary and published by . This book was released on 2014 with total page 319 pages. Available in PDF, EPUB and Kindle. Book excerpt: The discussion is divided into two types of prediction. In the first type statistical models for fatigue life prediction for welded joints are discussed and fitted to experimental data for fillet-welded steel joints where cracks emanate from the weld toe. The models are based on an S-N approach where the number of cycles N to failure is assumed to be directly correlated to the applied nominal stress range [Delta]S. The models assume the existence of a fatigue limit given as a stress range below which no failure will take place. Emphasis is laid on the modeling of the fatigue life close to this limit where the service stresses for welded details often occur. Experimental data in this stress regime are sparse and do not fit the knee point of the conventional bi-linear S-N curve found in design rules and specifications. Therefore, an alternative model where both the fatigue life and the fatigue limit are simultaneously treated as random variables is investigated. The model parameters for this random fatigue-limit model (RFLM) are determined by the maximum likelihood method, and confidence intervals are obtained by the profile likelihood method. The advantage of the model is that it takes into consideration the variation in fatigue limit found from specimen to specimen and that run-out results are easily included. The median S-N curve obtained from the model coincides with the conventional bi-linear curves in the high stress regime (stress ranges higher than 110 MPa), but predicts longer lives as the stress range decreases below 100 MPa. The model gives a nonlinear S-N curve for a log-log scale in the fatigue-limit area; the fatigue life is gradually increasing and is approaching a horizontal line asymptotically instead of the abrupt knee point of the bilinear curve. The nonlinear curve is more in accordance with experimental data. At stress ranges below 100 MPa, the predicted fatigue lives are between 2 to 10 times longer than predictions made by the bilinear Category E curve in AISC Steel Construction Manual. The conclusion is that the rule-based S-N curves may be un-conservative in the stress regime where service stresses frequently occur. A more correct statistical model based on a random fatigue-limit model results in S-N curves that give decreased dimensions for a given fatigue design factor under constant amplitude loading. The second type of prediction is required if inspection is to be carried out in a damage tolerance approach. In this case fatigue process in fillet welded joints is discussed and modeled. As a first approximation, a pure fracture mechanics model was employed to describe the entire fatigue process. The model is calibrated to fit the crack growth measurements obtained from extensive testing on fillet weld joints where cracks emanate from the weld toes. Emphasis is laid on the choice of growth parameters in conjunction with a fictitious initial crack size distribution in order to obtain both reliable crack growth histories and predictions of the entire fatigue life. The model has its shortcomings in describing the damage evolution at low stress ranges due to the presence of a significant crack development period in this stress regime. As an alternative to the fracture mechanics model, a two-phase model (TPM) for the fatigue process was developed and calibrated.
Download or read book Cohesive Model Based Prediction of Near Threshold Fatigue Crack Behavior written by Aniket Utkur and published by . This book was released on 2008 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ASME Technical Papers written by and published by . This book was released on 1999 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Paper written by and published by . This book was released on 1999 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Statistical Analysis of Fatigue Data written by Robert Eugene Little and published by ASTM International. This book was released on 1981 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Cycle Fatigue written by Theodore Nicholas and published by Elsevier. This book was released on 2006-07-07 with total page 657 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dr Theodore Nicholas ran the High Cycle Fatigue Program for the US Air Force between 1995 and 2003 at Wright-Patterson Air Force Base, and is one of the world's leading authorities on the subject, having authored over 250 papers in leading archival journals and books. Bringing his plethora of expertise to this book, Dr Nicholas discusses the subject of high cycle fatigue (HCF) from an engineering viewpoint in response to a series of HCF failures in the USAF and the concurrent realization that HCF failures in general were taking place universally in both civilian and military engines. Topic covered include: - Constant life diagrams - Fatigue limits under combined LCF and HCF - Notch fatigue under HCF conditions - Foreign object damage (FOD) - Brings years of the Author's US Air Force experience in high cycle fatigue together in one text - Discusses HCF in the context of recent international military and civilian engine failures
Download or read book NASA Technical Paper written by and published by . This book was released on 1986 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the Conference on the Design of Experiments written by and published by . This book was released on 1980 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technometrics written by and published by . This book was released on 2004 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Accelerated Testing written by Wayne B. Nelson and published by John Wiley & Sons. This book was released on 2009-09-25 with total page 626 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Applied Predictive Modeling written by Max Kuhn and published by Springer Science & Business Media. This book was released on 2013-05-17 with total page 595 pages. Available in PDF, EPUB and Kindle. Book excerpt: Applied Predictive Modeling covers the overall predictive modeling process, beginning with the crucial steps of data preprocessing, data splitting and foundations of model tuning. The text then provides intuitive explanations of numerous common and modern regression and classification techniques, always with an emphasis on illustrating and solving real data problems. The text illustrates all parts of the modeling process through many hands-on, real-life examples, and every chapter contains extensive R code for each step of the process. This multi-purpose text can be used as an introduction to predictive models and the overall modeling process, a practitioner’s reference handbook, or as a text for advanced undergraduate or graduate level predictive modeling courses. To that end, each chapter contains problem sets to help solidify the covered concepts and uses data available in the book’s R package. This text is intended for a broad audience as both an introduction to predictive models as well as a guide to applying them. Non-mathematical readers will appreciate the intuitive explanations of the techniques while an emphasis on problem-solving with real data across a wide variety of applications will aid practitioners who wish to extend their expertise. Readers should have knowledge of basic statistical ideas, such as correlation and linear regression analysis. While the text is biased against complex equations, a mathematical background is needed for advanced topics.
Download or read book Life Cycle Reliability Engineering written by Guang Yang and published by John Wiley & Sons. This book was released on 2007-02-02 with total page 533 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the Lead Reliability Engineer for Ford Motor Company, Guangbin Yang is involved with all aspects of the design and production of complex automotive systems. Focusing on real-world problems and solutions, Life Cycle Reliability Engineering covers the gamut of the techniques used for reliability assurance throughout a product's life cycle. Yang pulls real-world examples from his work and other industries to explain the methods of robust design (designing reliability into a product or system ahead of time), statistical and real product testing, software testing, and ultimately verification and warranting of the final product's reliability
Download or read book Interpretable Machine Learning written by Christoph Molnar and published by Lulu.com. This book was released on 2020 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is about making machine learning models and their decisions interpretable. After exploring the concepts of interpretability, you will learn about simple, interpretable models such as decision trees, decision rules and linear regression. Later chapters focus on general model-agnostic methods for interpreting black box models like feature importance and accumulated local effects and explaining individual predictions with Shapley values and LIME. All interpretation methods are explained in depth and discussed critically. How do they work under the hood? What are their strengths and weaknesses? How can their outputs be interpreted? This book will enable you to select and correctly apply the interpretation method that is most suitable for your machine learning project.
Download or read book Probability Distributions Used in Reliability Engineering written by Andrew N O'Connor and published by RIAC. This book was released on 2011 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book provides details on 22 probability distributions. Each distribution section provides a graphical visualization and formulas for distribution parameters, along with distribution formulas. Common statistics such as moments and percentile formulas are followed by likelihood functions and in many cases the derivation of maximum likelihood estimates. Bayesian non-informative and conjugate priors are provided followed by a discussion on the distribution characteristics and applications in reliability engineering.
Download or read book Thermal fatigue and Oxidation Resistance of Cobalt modified Udimet 700 Alloy written by Peter T. Bizon and published by . This book was released on 1986 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Resistance of Welded Details Under Variable Amplitude Long life Fatigue Loading written by and published by . This book was released on 1993 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Damage Crack Growth and Life Prediction written by F. Ellyin and published by Springer Science & Business Media. This book was released on 1996-11-30 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue failure is a multi-stage process. It begins with the initiation of cracks, and with continued cyclic loading the cracks propagate, finally leading to the rupture of a component or specimen. The demarcation between the above stages is not well-defined. Depending upon the scale of interest, the variation may span three orders of magnitude. For example, to a material scientist an initiated crack may be of the order of a micron, whereas for an engineer it can be of the order of a millimetre. It is not surprising therefore to see that investigation of the fatigue process has followed different paths depending upon the scale of phenomenon under investigation. Interest in the study of fatigue failure increased with the advent of industrial ization. Because of the urgent need to design against fatigue failure, early investiga tors focused on prototype testing and proposed failure criteria similar to design formulae. Thus, a methodology developed whereby the fatigue theories were proposed based on experimental observations, albeit at times with limited scope. This type of phenomenological approach progressed rapidly during the past four decades as closed-loop testing machines became available.
