The objective of this study was to evaluate the ability of three statistical distributions to characterize the vertical distribution of foliage mass in canopies of even-aged loblolly pine stands, based on airborne-scanning light detection and ranging (LiDAR) data. The functions were the Weibull and SB distributions and a mixture of the lognormal and Weibull distributions. Results indicated that...

It is extremely difficult to predict the initiation time of cracking due to a large time spread in most cracking experiments. Thus, probabilistic models, such as the Weibull distribution, are usually employed to model the initiation time of cracking. Therefore, the parameters of the Weibull distribution are estimated from data collected from a cracking test. However, although the development of...

The length data from 12 samples of wood fibers and particles were described using lognormal and Weibull distributions. While both distributions fitted the middle range of the data well, the lognormal distribution provided a closer fit for short fibers and particles and the Weibull distribution was more appropriate for long ones. A mixture of the lognormal and Weibull distributions was developed...

electric power industry have always try to provide reliable electricity to customers and at the same time decrease system costs. high voltage circuit-breakers are an essential part of the power network. this study has developed a maintenance and replacement scheduling model for high voltage circuit- breakers that minimize maintenance costs while maintaining the acceptable reliability. this mode...

Nowadays, the search for a distribution capable of modeling the probability density function (PDF) of irradiance data under all conditions of atmospheric turbulence in the presence of aperture averaging still continues. Here, a family of PDFs alternative to the widely accepted Log-Normal and Gamma-Gamma distributions is proposed to model the PDF of the received optical power in free-space optic...

I. MATHEMATICAL MODELS The mixture Weibull distribution produced from the combination has five or more parameters. These are; the shape parameters, scale parameters, location parameters, in addition to the mixing parameter (w). This type of distribution is even more useful because multiple causes of failure can be simultaneously modelled. Different values of the mixing parameter were used to ob...

This study aims to compare the predictive capability of two popular software reliability growth models (SRGM), say exponential growth and inflection S-shaped growth models. We first review the exponentiated Weibull (EW) testing-effort functions and discuss exponential type and inflection S-shaped type SRGM with EW testing-effort. We then analyzed the actual data applications and compare the pre...

We propose a new family of distributions referred to as Weibull taildistributions. This family is designed to model left tails with exponential behavior. The exponent can be estimated using inference procedures adapted from the Weibull tail-distributions literature. Let us define a negative Weibull tail-distribution through its distribution function by: F (x) = exp {

BACKGROUND The use of three-dimensional (3D) surface imaging is becoming more popular and accepted in the fields of Medicine and Dentistry. The present study aims to develop a technique to automatically localise and quantify soft-tissue asymmetry in adults using 3D facial scans. This may be applied as a diagnostic tool to monitor growth and dynamic changes and to evaluate treatment outcomes. ...