In this paper, we introduce a new class of lifetime distributions which is called the additive Weibull geometric (AWG) distribution. This distribution obtained by compounding the additive Weibull and geometric distributions. The new distribution has a number of well-known lifetime special sub-models such as modified Weibull geometric, Weibull geometric, exponential geometric, among several othe...

We introduce a new lifetime distribution by considering a serial system with one component following a Weibull distribution and another following a modified Weibull distribution. We study its mathematical properties including moments and order statistics. The estimation of parameters by maximum likelihood is discussed. We demonstrate that the proposed distribution fits two well-known data sets ...

The exponentiated -parent distribution is a generalization of the standard parent distribution. [7] introduced a simple generalization to weibull distribution namely the exponentiated weibull distribution. The new distribution was applied to analyzing bathtub failure rates lifetime data. In this paper, we consider the standard exponentiated inverted weibull distribution (EIW) that generalizes t...

Standard lifetime distributions usually very place strong restrictions on the data as is well illustrated by their inability to produce bathtub curves, and thus to adequately interpret data with this character. Mudholkar et al. (1995) introduced the exponentiated-Weibull distribution and Xie et al. (2002) proposed the new Weibull extension distribution. The new Weibull extension distribution wi...

The Generalized Renewal Process (GRP) is a probabilistic model for repairable systems that can represent the usual states of a system after a repair: as new, as old, or in a condition between new and old. It is often coupled with the Weibull distribution, widely used in the reliability context. In this paper, we develop novel GRP models based on probability distributions that stem from the Tsal...

Two important wood properties are the modulus of elasticity (MOE) and the modulus of rupture (MOR). In the past, the statistical distribution of the MOE has often been modeled as Gaussian, and that of the MOR as lognormal or as a twoor three-parameter Weibull distribution. It is well known that MOE and MOR are positively correlated. To model the simultaneous behavior of MOE and MOR for the purp...

The typical experimental procedure for testing stress corrosion cracking initiation involves an interval-censored reliability test. Based on these test results, the parameters of a Weibull distribution, which is a widely accepted crack initiation model, can be estimated using maximum likelihood estimation or median rank regression. However, it is difficult to determine the appropriate number of...

Recently, several attempts have been made to define new models that extend well-known distributions and at the same time provide great flexibility in modelling real data. We propose a new four-parameter model named the Weibull-power function (WPF) distribution which exhibits bathtub-shaped hazard rate. Some of its statistical properties are obtained including ordinary and incomplete moments, qu...

Background: Thalassemia major (TM) is a severe disease and the most common anemia worldwide. The survival time of the disease and its risk factors are of importance for physicians. The present study was conducted to apply the semi-parametric Cox PH model and use parametric proportional hazards (PH) and accelerated failure time (AFT) models to identify the risk factors related to survival of TM ...

The authors will demonstrate how a major Chemical Process company has successfully utilized this new technique to answer questions such as: 1. Do I have a reliability problem or a production problem? 2. What is the demonstrated capacity of my plant? 3. What are efficiency/utilization losses costing me? 4. What is the reliability of my process plant? The Weibull technique described has helped th...