The aim of this paper is to investigate adhesion property between nano-layered filler and the polymer matrix using a combination of experimental and micromechanical models as well as the changes in yield strength and stiffness of a layered silicate-filled epoxy nanocomposite. The results indicate that addition of intercalated layered silicate particles increased Young’s modulus and yield streng...

In $1994,$ degree distance  of a graph was introduced by Dobrynin, Kochetova and Gutman. And Gutman proposed the Gutman index of a graph in $1994.$ In this paper, we introduce the concepts of  multiplicative version of degree distance and the multiplicative version of Gutman index of a graph. We find the sharp upper bound for the  multiplicative version of degree distance and multiplicative ver...

This paper considers the Economic Lot Scheduling Problem, that is, the problem of scheduling several products on a single facility so as to minimize holding and setup costs. Combination of frequency and timing as well as production quantity make this problem Np-hard. A heuristic is developed to obtain a good solution to ELSP. The proposed heuristic makes use of the Simulated Annealing Technique...

Equality of opportunity is an important normative ideal distributive justice. In spite its wide acceptance and economic relevance, standard estimation approaches suffer from data limitations that can lead to both downward upward biased estimates inequality opportunity. These shortcomings may be particularly pronounced for emerging economies in which comprehensive household survey sufficient sam...

While a great portion of the scheduling literature focuses on time-based criteria, the most important goal of management is maximizing the profitability of the firm. In this paper, the net preset value criterion is studied taking account of linear time-dependent cash flows in single machine and flow shop scheduling problems. First, a heuristic method is presented for the single machine scheduli...

nowadays, scheduling problems have a considerable application in production and service systems. in this paper, we consider the scheduling of n jobs on a single machine assuming no machine idleness, non-preemptive jobs and equal process times. in many of previous researches, because of the delivery dalays and holding costs, earliness and tardiness penalties emerge in the form of linear combinat...

In this paper, an upper bound approach is used to analyze the extrusion process of bimetallic rods through arbitrarily curved dies. Based on a spherical velocity field, internal, shearing and frictional power terms are calculated. The developed upper bound solution is used for calculating the extrusion force for two types of die shapes: a conical die as a linear die profile and a streamlined di...

Unemployment is one of the most important economic problems in Iran, so that many of its managers plan to increase employment rates. Increasing the employment rate needs to increase economic productivity which DEA is one of the most appropriate evaluation methods for estimating the productivity of similar organizations. Employment in the amount of data input and output can be just interval. In ...