Sharif Digital Repository

Economics have been thought about market, trade and money in many eras. During years, several issues regarding markets and making economic decisions have become more complicated, due to population growth and changes in market structure.we are going to discuss the classic model of Cournot in social networks in two competence companies which both produce identical products. Each individual considers a value for each product. lf friend it an individual buy a product then it can effect the individual's value of product. In this model, each company decides on quantity of its products and the selling price of products is calculated based on the amount of all productions. In Cournot model, at the... 

As aircraft fleets get older, the challenge of Flight Safety gets greater. This Thesis focus on management strategies and principles to keep long-life fleet safe and effective into old age. But the safety and efficacy are not the only ones who are considered at long-life fleet. Here the question arises why the aircraft prior to exposure to the effects of rising life expectancy, are not replaced by other aircraft.The reason is the high cost of the replacement. Aircraft are expensive to design and manufacture. In commercial aviation, extreme competition and miniscule profit force pressures to delay replacement of older aircraft with expensive new types. But in Military aircraft reason for...