This paper considers a two-stage assembly flow shop scheduling problem. When all parts of each product are completed in the first stage, they are assembled into a final product on an assembly machine in the second stage. In order to reduce the delivery cost, completed products can be held until completion of some other products to be delivered in a same batch. The proposed problem addresses sch...

In order to study the effects of three operations of rangelands on the properties of vegetation in rangelands, this research was conducted in Chaat Gonbad, Golestan province, Iran in 2004. Chaat area is located in 50 km of border road of Dashlibroun to Maravetappeh in North of Attract River (border of Iran and Turkmenistan). The Altitude is 70 m, annual rainfall is 170 mm and annual temperature...

The enhanced principal rank characteristic sequence (epr-sequence) of an n× n symmetric matrix over a field F was recently defined as `1`2 · · · `n, where `k is either A, S, or N based on whether all, some (but not all), or none of the order-k principal minors of the matrix are nonzero. Here, a complete characterization of the epr-sequences that are attainable by symmetric matrices over the fie...

Warranty is a powerful implement for marketing strategy that is used by manufacturersand creates satisfaction for consumers by ensuring to compensate for incorrect operation of the product. Warranty serviceresults ina cost named warranty cost for a manufacturer.This cost is a function of warranty policy, regions, and product failures pattern. Since this service coversthe cost of uncertain failu...