Predictive Microbiology (PM) deals with the mathematical modeling of microorganisms in foods for different applications (challenge test, evaluation of microbiological shelf life, prediction of the microbiological hazards connected with foods, etc.). An interesting and important part of PM focuses on the use of primary functions to fit data of death kinetics of spoilage, pathogenic, and useful m...

Lower bounds are typically used to evaluate the performance of heuristics for solving combinatorial minimization problems. In the absence of tight analytical lower bounds, optimal objective-function values may be estimated statistically. In this paper, extreme value theory is used to construct confidence-interval estimates of the minimum makespan achievable when scheduling nonsimilar groups of ...

The purpose of this study was to investigate and analyse the fracture toughness of yttria stabilized tetragonal zirconia polycrystal (Y-TZP) dental ceramics by means of the Vickers indentation technique. Fracture toughness was analysed under the following loads: 29.42 N, 49.03 N, 196.13 N, and 294.20 N. Cracks that had developed from the vertices of a Vickers indentation were measured and used ...

The Weibull distribution is widely used in reliability and life data analysis due to its versatility. And, this distribution has been considered as a popular life time distribution which describes modeling phenomena with monotonic failure rates of components. Depending on the values of the parameters it can be used to model a variety of life behaviors. In this paper, reliability measures such a...

Modelling daily wind speed data by using the two parameter Weibull distribution for ten selected weather stations in Sri Lanka is presented. The daily wind speed data measured by the Department of Meteorology at the heights of 6m-15m during the years 2001 and 2004 were used in this work. The annual variation of the fitted Weibull parameters, the shape parameter k and the scale parameter c range...

We introduce a method to combine the color channels of an image to a scalar valued image. Linear combinations of the RGB channels are constructed using the Fisher-Trace-Information (FTI), defined as the trace of the Fisher information matrix of the Weibull distribution, as a cost function. The FTI characterizes the local geometry of the Weibull manifold independent of the parametrization of the...

Estimation of mixed Weibull distribution by maximum likelihood estimation and other methods is frequently difficult due to unstable estimates arising from limited data. Bayesian techniques can stabilize these estimates through the priors, but there is no closed-form conjugate family for the Weibull distribution. This paper reduces the number of numeric integrations required for using Bayesian e...

In this paper, the test purpose will be to assess whether or not the accelerated model proposed by Eyring will be able to translate results for the shape and scale parameters of an underlying Weibull model, obtained under two accelerating using conditions, to expected normal using condition results for these parameters. The product being analyzed is a new type of insulate fluid, and the acceler...

A two-sided Weibull is developed to model the conditional financial return distribution, for the purpose of forecasting Value at Risk (VaR) and conditional VaR. A range of conditional return distributions are combined with four volatility specifications to forecast tail risk in four international markets, two exchange rates and one individual asset series, over a four year forecast period that ...

In many pharmaceutical studies, non-inferiority clinical trials are usually conducted because of the difficulty of finding a therapy that has more superior efficacy than a recognized effective one. When planning the non-inferiority clinical trials with a time-to-event endpoint, the calculation of sample size is one of the most fundamental steps. A proper sample size provides reasonable power to...