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Generalized Renewal Processes are useful for approaching the rejuvenation of dynamical systems resulting from planned or unplanned interventions. We present new perspectives for the Generalized Renewal Processes in general and for the Weibull-based Generalized Renewal Processes in particular. Disregarding from literature, we present a mixed Generalized Renewal Processes approach involving Kijima Type I and II models, allowing one to infer the impact of distinct interventions on the performance of the system under study. The first and second theoretical moments of this model are introduced as well as its maximum likelihood estimation and random sampling approaches. In order to illustrate the usefulness of the proposed Weibull-based Generalized Renewal Processes model, some real data sets involving improving, stable, and deteriorating systems are used.

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RESUMOObjetivo: caracterizar função, práticas e posições sexuais de mulheres grávidas. Método: revisão integrativa realizada em abril de 2017, nas bases de dados MEDLINE, Lilacs, IBECS, CINAHL, BDENF e biblioteca virtual SciELO. Identificaram-se 1.439 artigos, após aplicação dos filtros, critérios de inclusão e exclusão, 11 artigos compuseram amostra. Resultados: os resultados evidenciaram quatro categorias temáticas << Práticas sexuais na gestação >>; << Posições sexuais na gestação >>; << Domínios da função sexual >> e << Aspectos correlatos da função sexual >>. Conclusão: durante a gestação ocorre redução na frequência e/ou restrição de realização de práticas e posições sexuais, além de alterações em todos os domínios e aspectos correlatos da função sexual. Práticas e posições sexuais não foram avaliadas e/ou especificadas pela maioria dos estudos primários. Descritores: Atenção à Saúde; Saúde da Mulher; Gravidez; Sexualidade; Comportamento Sexual; Revisão.ABSTRACTObjective: to characterize the function, practices and sexual positions of pregnant women. Method: this is an integrative review performed in April 2017, in the MEDLINE, Lilacs, IBECS, CINAHL, BDENF and SciELO virtual libraries. There were 1,439 articles identified. After the application of the filters, inclusion, and exclusion criteria, 11 articles composed the sample. Results: the results showed four thematic categories << Sexual practices during pregnancy >>; << Sexual positions during pregnancy >>; << Sexual Function domains >> and << Related Aspects of Sexual Function >>. Conclusion: during pregnancy, there is a reduction in the frequency and/or restriction of sexual practices and positions, besides to changes in all domains and related aspects of sexual function. Sexual practices and positions have not been evaluated and/or specified by most primary studies. Descriptors: Women's health; Pregnancy; Sexuality; Sexual behavior; Review.RESUMENObjetivo: caracterizar función, prácticas y posiciones sexuales de mujeres embarazadas. Método: revisión integradora realizada en abril de 2017, en las bases de datos MEDLINE, Lilacs, IBECS, CINAHL, BDENF y biblioteca virtual SciELO. Se identificaron 1.439 artículos, después de la aplicación de los filtros, criterios de inclusión y exclusión, 11 artículos compusieron la muestra. Resultados: los resultados mostraron cuatro categorías temáticas << Prácticas sexuales en el embarazo >>; << Posiciones sexuales en el embarazo >>; << Dominios de la función sexual >> y << Aspectos correlatos de la función sexual >>. Conclusión: durante la gestación ocurre reducción en la frecuencia y o restricción de realización de prácticas y posiciones sexuales, además de alteraciones en todos los dominios y aspectos correlatos de la función sexual. Prácticas y posiciones sexuales no fueron evaluadas y o especificadas por la mayoría de los estudios primarios. Descriptores: Atención a la Salud; Salud de la mujer; Embarazo; Sexualidad; Comportamiento sexual; Revisión.

Human factors always affect maintenance performance, and in some cases, it's critical to systems availability and reliability. Despite such importance, in so many cases, there's no human reliability method applied to analyze maintenance tasks in order to understand better human factors influence in maintenance performance. There are several human analysis methodologies and regarding human factors, SLIM (Successes Likelihood Methods), SPAR-H (Standardized Plant Analysis Risk-Human Reliability Analysis Method) and Bayesian Net take into account such factors and may be a good approach to minimize human error. In order to propose a human reliability methodology to analyze maintenance tasks taking into account human factors, a case study about turbine star up tasks will be carried out. Therefore, different human reliability methods will be performed based on specialist opinion. Finally, the human error probability as well as drawbacks and advantages from different methods will be discussed to get a final conclusion.

This article develops a model for dependent and imperfect condition-based preventive and corrective maintenance actions. The approach is based on the combination of the intensity proportional repair alert, a competing risks-based model and the generalized renewal process. Typically, intensity proportional repair alert can identify either how preventive actions may modify the distribution of the time between critical failures or how corrective events may change the frequency of preventive maintenances, but this method fails to analyze the effectiveness of the maintenance actions because they are treated as being perfect. On the other hand, generalized renewal process is able to capture the quality of maintenance, classifying it as perfect, minimal or imperfect depending on the value of a rejuvenation parameter. However, generalized renewal process cannot distinguish how different types of maintenance influence each other as intensity proportional repair alert does. Therefore, the intensity proportional repair alert-generalized renewal process hybrid approach is proposed here to fill this gap. This article also develops the maximum likelihood estimators for the proposed model as well as a Monte Carlo-based algorithm to estimate the expected number of preventive and corrective maintenances over time. The proposed model is validated through two example applications for which the intensity proportional repair alert-generalized renewal process model results show close agreement with the failure datasets.

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