The Swedish physicist, Waloddi Weibull, is renowned for formulating a family of probability distributions for modelling the variability of nonnegative, quantitative, random phenomena (see reference 3). The distribution was originally designed to model the breaking strength of steel (Weibull was scientific advisor to Bofors, the Swedish steel company) but, since then, Weibull analysis has evolve...

Escherichia coli, as a model microorganism, was treated in phosphate-buffered saline under high hydrostatic pressure between 100 and 300 MPa, and the inactivation dynamics was investigated from the viewpoint of predictive microbiology. Inactivation data were curve fitted by typical predictive models: logistic, Gompertz and Weibull functions. Weibull function described the inactivation curve the...

In assessing the insulation withstand level of the electric apparatus, the step-up test method is used. However, we have still many unknown matters regarding the treatment of the results. In this paper, we assume that the underlying probability distribution of failure time with a constant voltage level follows a Weibull distribution and that an inverse power law relationship between the mean li...

The application of continuous time Weibull models on discrete unemployment duration data may produce bias in the estimated shape of the hazard rate. The bias can be substantial even for weekly duration data, and it is seriously aggravated if the Weibull model is erroneously mixed with a Gamma distribution for unobserved heterogeneity.

This paper deals with a two-warehouse inventory model for deteriorating items with time dependent demand and partial backlogging under inflation. It is assumed that deterioration of items follows two-parameter Weibull distribution and demand rate varies exponentially with time. Shortages are allowed and partial backlogging depends on waiting time of next replenishment. A numerical example is pr...

Weibull distributions can be used to accurately model failure behaviours of a wide range of critical systems such as on-orbit satellite subsystems. Markov chains have been used extensively to model reliability and performance of engineering systems or applications. However, the exponentially distributed sojourn time of Continuous-Time Markov Chains (CTMCs) can sometimes be unrealistic for satel...

Parametric survival models have not previously been applied to survival following a diagnosis of HIV/AIDS in Australia. Four different parametric models--exponential, Weibull, log-normal and log-logistic--were applied to data both on HIV-positive cases and on cases diagnosed with AIDS collected through the national HIV/AIDS surveillance system. Using likelihood based goodness-of-fit criteria th...

The paper considers a group of patients suffering from leukemia B non-small lung cancer. Such patients are generally suggested to undergo for either radiotherapy or chemotherapy followed by radiotherapy. The objective of the paper is to compare the two therapies based on survival functions of the patients assuming Weibull survival model for each therapy. The paper further examines the feasibili...