On Bivariate Exponentiated Extended Weibull Family of Distributions

In this paper, we introduce a new class of bivariate distributions called the bivariate exponentiated extended Weibull distributions. The model introduced here is of Marshall-Olkin type. This new class of bivariate distributions contains several bivariate lifetime models. Some mathematical properties of the new class of distributions are studied. We provide the joint and conditional density functions, the joint cumulative distribution function and the joint survival function. Special bivariate distributions are investigated in some detail. The maximum likelihood estimators are obtained using the EM algorithm. We illustrate the usefulness of the new class by means of application to two real data sets.Comment: arXiv admin note: text overlap with arXiv:1501.03528 by other author

Exponentiated Extended Weibull-Power Series Class of Distributions

In this paper, we introduce a new class of distributions by compounding the exponentiated extended Weibull family and power series family. This distribution contains several lifetime models such as the complementary extended Weibull-power series, generalized exponential-power series, generalized linear failure rate-power series, exponentiated Weibull-power series, generalized modified Weibull-power series, generalized Gompertz-power series and exponentiated extended Weibull distributions as special cases. We obtain several properties of this new class of distributions such as Shannon entropy, mean residual life, hazard rate function, quantiles and moments. The maximum likelihood estimation procedure via a EM-algorithm is presented.Comment: Accepted for publication Ciencia e Natura Journa

Reliability-centered maintenance: analyzing failure in harvest sugarcane machine using some generalizations of the Weibull distribution

In this study we considered five generalizations of the standard Weibull distribution to describe the lifetime of two important components of harvest sugarcane machines. The harvesters considered in the analysis does the harvest of an average of 20 tons of sugarcane per hour and their malfunction may lead to major losses, therefore, an effective maintenance approach is of main interesting for cost savings. For the considered distributions, the mathematical background is presented. Maximum likelihood is used for parameter estimation. Further, different discrimination procedures were used to obtain the best fit for each component. At the end, we propose a maintenance scheduling for the components of the harvesters using predictive analysis

Reliability analysis of structural ceramic components using a three-parameter Weibull distribution

Described here are nonlinear regression estimators for the three-Weibull distribution. Issues relating to the bias and invariance associated with these estimators are examined numerically using Monte Carlo simulation methods. The estimators were used to extract parameters from sintered silicon nitride failure data. A reliability analysis was performed on a turbopump blade utilizing the three-parameter Weibull distribution and the estimates from the sintered silicon nitride data

Reliability vs. Total Quality Cost: part selection criteria based on field data, combined optimal customer and business solution

Most privately owned businesses are formed to generate profits. Every year, manufacturers loose a portion of potential profits on covering warranty claims. To minimize warranty costs companies focus on product quality improvements. In this project real historical warranty data of three electronic sensors have been analyzed. Two-parameter Weibull distribution to measure sensors’ reliability have been used. Monte Carlo simulations have been implemented to calculate Total Quality Costs (TQC). The results show that cost of improved products may have an adverse impact on business profit – the main business objective. It has been demonstrated how reliability and TQC interact with each other and specified optimum business solutions. A new ratio representing combined business and customer objectives was introduced – Quality Cost Ratio (QCR). A new term has been proposed – Excessive Quality Cost (EQC). Improved process of selection parts and materials were proposed