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The extrusion process of plastic transformation involves a series of variables and components which must be associated with the concept of reliability to achieve an expected performance in operational and quality terms. This paper describes the reliability framework of an extruder of a packaging company located in Brazil through the following mathematical representations: probability density function f(t), reliability curve R(t) and function rate of failure h(t). Through a statistical software the set of representations was able to develop the reliability framework of the machine, which can be used to support a FMEA analysis. Besides that, it was evidenced that in the current operating conditions of the machine, approximately 50% of the failure observations happen on the hour 100 of operating time. The main outcome is that it is recommended a systematic preventive maintenance based on 100h cycles. It is expected that this work may act as a guide for future implementation of improvement activities. [ABSTRACT FROM AUTHOR]

This paper presents a probabilistic analysis of pile foundations in the design phase considering Reliability Theory in order to improve the final decision about the foundation system. Two semi-empirical predicting methods of pile bearing capacity were used and the Standard Penetration Test (SPT) was applied for site characterization and definition of the uncertainties on the soil strength parameters. The First Order Reliability Method (FORM) was adopted for assessing the probability of failure in the reliability analyses phase. The design of the foundation elements for a three floors hypothetical building designed in reinforced concrete and installed in a sandy soil profile is presented to show how the proposed probabilistic approach can be applied in a practical case. The distributions of the random variables defined by the NSPT values as well as the shaft and base resistances of the piles were calculated by the two mostly used semi-empirical method in Brazil for bearing capacity prediction. The reliability analysis allowed to identify the differences in the prediction methods and provided the probability estimative for each isolated pile. It was observed that the values for reliability indexes and failure probabilities of isolated foundation elements depend directly on the approach for determining the variability of the pile-soil resistance parameters. The main advantage of this approach is to adapt the foundation design, in which the number of piles, as well as its diameter or length can be redefined to achieve the chosen target probability of failure. [ABSTRACT FROM AUTHOR]

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The Behçet’s Disease Current Activity Form (BDCAF) is a clinical instrument used to assess the activity of Behçet’s disease (BD), which was originally developed in English. The aim of the present study was to perform a cross-cultural adaptation of the BDCAF to Brazilian Portuguese language and to evaluate its reliability in a population of Brazilian patients with BD. Brazilian Portuguese version of the BDCAF, named BR-BDCAF, was obtained according to established guidelines. Forty Brazilian patients with BD diagnosed according to the International Study Group for Behçet’s Disease criteria were assessed by two rheumatologists in independent sessions and submitted to the BR-BDCAF. Inter- and intraobserver agreement were then evaluated by kappa scores (values higher than 0.6 indicated good agreement). Good inter- and intraobserver agreements were achieved for the most common manifestations of BD: kappa scores higher than 0.6 were obtained for oral and genital ulcerations, skin lesions, and articular and general complaints. Moderate interobserver agreement was obtained for ocular activity (kappa 0.483) and fair interobserver agreement was obtained for gastrointestinal (kappa 0.322), major vessel (kappa 0.281), and central nervous system activity (kappa 0.304). BR-BDCAF was found to be a reliable instrument for the classic mucocutaneous and articular manifestations of BD and for general complaints, but complementary assessment is needed to evaluate specific visceral involvement for disease activity. [ABSTRACT FROM AUTHOR]

This article presents a reliability analysis of 116 full-scale pond systems in Brazil, comprising 73 primary facultative ponds and 43 anaerobic--facultative pond systems. A methodology developed by Niku et al. (1979) is used for the determination of the coefficients of reliability, in terms of the compliance of effluent BOD, COD, TSS and FC to discharge standards or effluent quality targets. The design concentrations necessary to meet the prevailing discharge standards and the expected compliance percentages have been calculated from the coefficients of reliability obtained. The results showed that few units, under the observed operating conditions, would be able to present reliable performances in terms of compliance with the analyzed standards. For the four constituents (BOD, COD, TSS and FC) and both systems (facultative ponds and anaerobic-facultative systems), the variability of the effluent quality was very large, leading to a high variability of the coefficient of variation (CV) and the coefficient of reliability (COR). The effluent quality from the facultative ponds showed a larger distance to both the desired values and the discharge standard values, compared with the anaerobic--facultative systems. [ABSTRACT FROM AUTHOR]