The Weibull distribution is widely employed in several areas of engineering because it is an extremely flexible distribution with different shapes. Moreover, it can include characteristics of several other distributions. However, successful usage of Weibull distribution depends on estimation accuracy for three parameters of scale, shape and location. This issue shifts the attentions to the requ...

Development of distributed generations’ technology, trends in the use of these sources to improve some of the problems such as high losses, low reliability, low power quality and high costs in distributed networks. Choose the correct location to install and proper capacity of these sources, such as important things that must be considered in their use. Since distribution networks are actu...

in this paper, we develop an inventory model for perishable items with random lifetime in a two-echelon production-distribution system. there is a manufacturer at the first stage that produces its product with a constant rate. deterioration in this stage is modeled via a two-parameter weibull distribution. at the second stage, the retailer places the order and receives the product instantly. th...

The present paper is intended to present a robust multiplicative video watermarking scheme. In this regard, the video signal is segmented into 3-D blocks like cubes, and then, the 3-D wavelet transform is applied to each block. The low frequency components of the wavelet coefficients are then used for data embedding to make the process robust against both malicious and unintentional attacks. Th...

We explore the idea that the power-law tail in the mass function of protostellar condensations and stars arises from the accretion of ambient cloud material on to a condensation, coupled with a nonuniform (exponential) distribution of accretion lifetimes. This model allows for the generation of power-law distributions in all star-forming regions, even if condensations start with a lognormal mas...

.Hot metal gas forming of tubes can be used in various industries such as automotive and aerospace industries. In this process tube is formed at elevated temperatures, by using gas instead of fluid pressure. Lower required pressure and low power are its advantages in comparison to hydroforming process. In this paper, a hot metal gas bulging process of an aluminum alloy tube has been investigate...