[en] Failure of systems is undesirable, but also inevitable. The consequences of failure can be reduced if the failure mode can be anticipated and repair procedures planned in advance. The fault tree analysis is one method of identifying the most probable failure modes and determining system failure rates. From these rates, repair frequency can be estimated. (author)

[en] The calculating rules and recommendations of this standard act as guidelines for a quantitative probability analysis of failure sequences based on event trees in accodance with DIN-25419 (Pt.1)

[en] Failure mode and effects analysis is a method to investigate the possible types of component failures and their effects on the system. The analysis is an inductive procedure. The analysis postulates failure of single components. The types of component failure are unlimited. It is a simple procedure without great mathematical efforts. Standard forms are used for systematic working, clearness, and documentation. Recommendations are given concerning the methods of failure mode and effects analysis and the design of the standard form. (orig./HP)

[en] Common cause failure analysis, also called common mode failure analysis, is an integral part of a complete system reliability analysis. Existing methods of computer aided common cause failure analysis are extended by allowing analysis of the complex systems often encountered in practice. The methods aid in identifying potential common cause failures and also address quantitative common cause failure analysis

[en] Common mode failures (CMFs) have been a serious concern in the nuclear power plant. Thereis a broad category of the failure mechanisms that can cause common mode failures. This paper is a theoretical investigation of the CMFs on the unavailability of the redundent system. It is assumed that the total CMFs consist of the potential CMFs and the dependent human error CMFs. As the human error dependency is higher, the total CMFs are more effected by the dependent human error. If the human error dependence is lower, the system unavailability strongly depends on the potential CMFs, rather than the mechanical failure or the dependent human error. And it is shown that the total CMFs are dominant factor to the unavailability of the redundent system. (Author)

[en] A centrifuge test at a constant acceleration level that bounds from above the closure that would be experienced by a normally open switch subjected to a stationary random excitation of fixed duration is derived. The bound is probabilistic in that the induced displacement will be exceeded with a certain selectable probability. The bound was formulated in terms of the system modal properties. Because the spatial distribution of the excitation is smooth and the frequency content is wide band the response is dominated by the first few lowest modes of the structure. It is further shown that the bound is relatively insensitive to the selected desired reliability. Experiments which verify the validity of the bound have been performed

[en] The decline in industrial efficiency may be linked to decreased reliability of complex automatic systems. This decline threatens the viability of complex organizations in industrialized economies. Industrial engineering techniques that minimize system failure by increasing the reliability of systems hardware are well developed in comparison with those available to reduce human operator errors. The problem of system reliability and the associated costs of breakdown can be reduced if we understand how highly skilled technical personnel function in complex operations and systems. The purpose of this research is to investigate how human errors are affected by deadline pressures, technical communication and other socio-dynamic factors. Through the analysis of a technologically complex particle accelerator prototype at Brookhaven National Laboratory, two failure mechanisms: (1) physical defects in the production process and (2) human operator errors were identified. Two instruments were used to collect information on human failures: objective laboratory data and a human failure questionnaire. The results of human failures from the objective data were used to test for the deadline hypothesis and also to validate the human failure questionnaire. To explain why the human failures occurred, data were collected from a four-part, closed choice questionnaire administered to two groups of scientists, engineers, and technicians, working together against a deadline to produce an engineering prototype of a particle accelerator

[en] The eigenstructure of the Gram matrix of frequency exponentials is used to study linear vibrating systems of hyperbolic type with distributed control. Using control norm as a practical measure of controllability and the vibrating string as a prototype, it is demonstrated that hyperbolic systems have a natural control time, even when only finitely many modes are excited. For shorter control times there are identifiable control failure modes which can be steered to zero only with very high cost in control norm. Both natural control time and the associated failure modes are constructed for linear fluids, strings, and beams, making note of the essential algorithms and Mathematica code, and displaying results graphically

[en] Recent plate impact experiments have been interpreted as indicating the existence of open-quotes failure wavesclose quotes during the compression of glass by impact at sufficiently high velocities. In experiments on soda-lime glass, Brar et al. reported the propagation of a wave across which the shearing strength dropped sharply from 2 GPa to 1 GPa, and the spall strength dropped from 3 GPa to zero. Such a drop in spall strength has also been reported by Raiser et al. in an aluminosilicate glass. Kanel et al. interpreted a small jump in the rear surface particle velocity in experiments on K19 glass as the reflection of a recompression wave from a wavefront propagating at approximately the speed reported for open-quotes failure wavesclose quotes. In this paper, such open-quotes failure wavesclose quotes are interpreted within the context of nonlinear wave theory. In this theory the open-quotes failure waveclose quotes corresponds to a propagating phase boundary-called a transformation shock. The theory is analogous to the theory of liquifaction shocks in fluids. 18 refs., 5 figs

No abstract available