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Über dieses Buch

The aim of the book is to develop methodology for reliablity analysis which is particularly suited to the types of partial information characteristic of mechanical systems and structures.
The book is designed as an upper-level undergraduate or first-year graduate text on robust reliability of mechanical systems. It will give the student or engineer a working knowledge of robust reliability which will enable him to analyse the reliability of mechanical systems. Each chapter is introduced with a brief conceptual survey of the main ideas, which are then developed through examples. Problems at the end of each chapter give the student the opportunity to strengthen and extend his or her understanding.

Inhaltsverzeichnis

Frontmatter

Chapter 1. Preview of Robust Reliability

Abstract
Technological systems are designed to perform well-defined tasks. However, these systems and their environments are often inordinately complex, and the designer invariably suffers from incomplete knowledge of the properties of the system and its environmental conditions. One aim of reliability analysis and design is to enhance the robustness of the system to the uncertainties inherent in limited information. A system is reliable if it is robust with respect to these uncertainties. In other words, a system is reliable if it will perform satisfactorily in the presence of large uncertainties. On the other hand, a system is unreliable if it can fail due to even small deviations from nominal circumstances.
Yakov Ben-Haim

Chapter 2. Convexity and Uncertainty

Abstract
If you ask a person, ‘what do you know?’ he can tell you. If you ask him, ‘what do you not know?’ what can he say? The phenomena of uncertainty lie in that tantalizing gap between what we do know and what we could know.
Yakov Ben-Haim

Chapter 3. Robust Reliability of Static Systems

Abstract
Mechanical systems are hardly ever designed to fail. Failure occurs because the system differs from its nominal design, or because the operational environment changes, or the system is altered in some way, or unanticipated or extraordinary loads are applied. The robust reliability of a system is a measure of its resistence to these uncertainties. The system is reliable if it can tolerate a large amount of uncertainty without failing. On the other hand, a system is not reliable if it is fragile with respect to uncertainty; it is unreliable if failure becomes a possibility as a result of small deviations from nominal circumstances.
Yakov Ben-Haim

Chapter 4. Robust Reliability of Time-Varying Systems

Abstract
In chapter 3 we studied the robust reliability of primarily static systems with time-invariant uncertainties. In the present chapter we will consider time-varying uncertainties and dynamic systems or processes which evolve in time. In sections 4.1 to 4.3 we consider linear elastic vibrations driven by uncertain time-varying loads. Uncertainties may exist in both the inputs and the failure states of the structure, which will lead to the ideas of input reliability and failure reliability, as well as the overall reliability of the system. When we consider general multi-dimensional systems we will assess the relative reliability of the individual modes or degrees of freedom, which is developed in section 4.4. In section 4.5 we study the reliability of dynamic buckling of an axially loaded shell. In section 4.6 we develop the robust reliability of a dynamically loaded structure which is vulnerable to fatigue failure under uncertain repetitive loading.
Yakov Ben-Haim

Chapter 5. Fault Diagnosis, System Identification and Reliability Testing

Abstract
The analysis of reliability assists the designer to make ratiońal decisions for optimizing the performance of his system. However, even in the best of circumstances, not everything can be planned or anticipated, and the most carefully designed device may go awry if left unattended. Fault diagnosis and the monitoring of system integrity are essential for reliable operation.
Yakov Ben-Haim

Chapter 6. Reliability of Mathematical Models

Abstract
Models of mechanical systems are developed for various purposes, including design, safety assessment, dynamic analysis and so on. No model is perfect, and model inaccuracy reduces the reliability of decisions based on the model. Furthermore, there is no unique definition of the accuracy of a model. Rather, model inaccuracy should be evaluated with respect to the intended use of the model. In this chapter we will evaluate the reliability of models in terms of the robustness-to-uncertainty of decisions based on the model.
Yakov Ben-Haim

Chapter 7. Convex and Probabilistic Models of Uncertainty

Abstract
The theory of probability is a prize flower in the garden of mathematics. Many of the most creative mathematicians have contributed to this theory, which is characterized by a subtle combination of intuition and analysis. The engineers acquired the theory of probability fairly recently from the scientists (who got it from aristocratic 17th century gamblers!) and have found it immensely useful. However, as we have seen in the previous chapters, probability is not the only mathematical tool with which we can quantify uncertainty. Robust reliability is derived from convex rather than probabilistic models of uncertainty.
Yakov Ben-Haim

Chapter 8. Robust Reliability and the Poisson Process

Abstract
Throughout the first 6 chapters we have exclusively used convex models of uncertainty. The primary practical motivation for avoiding the use of probabilistic models is the frequent lack of sufficient information to verify the choice of the probabilistic model. In chapter 7 we demonstrated that even small inaccuracies in the probability density can have far reaching repercussions on the reliability analysis.
Yakov Ben-Haim

Chapter 9. Last but Not Final

Abstract
We begin this chapter with a brief recapitulation of robust reliability, after which we address several remaining issues whose nature requires a somewhat more speculative approach than that adopted in previous chapters.
Yakov Ben-Haim

Backmatter

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