In most gravity model applications, general equilibrium effects are disregarded altogether or ”controlled for” by country or country-time fixed effects, and the parameter estimates on observable trade cost variables are falsely interpreted as reduced-form marginal effects rather than only direct effects of such variables on trade. This paper proposes an empirical approach which employs panel da...

To illustrate these assumptions, let us consider a simple numerical example. Suppose a car is needed for three years; that is, suppose N = 3. At the beginning of the first year, we have a 2-year-old car. The annual cost of operating a car is a function of its age; and this cost function is given by: c(0) = 10, c(1) = 20, c(2) = 40, c(3) = 60, and c(4) = 70. The fact that these costs are increas...

this study concerns with calculation of iran's agricultural bilateral trade costs and major influential factors in iran's bilateral trade with developed and developing countries. the main findings revealed that over the period 1995-2010 weighted average of agricultural trade cost with developing partners has declined by 44, and with developed partners has increased by 22 percent. this reduction...

Today, the construction industry is facing intense competition and success in this competition depends on several factors. Project managers try to minimize project time and cost, carbon dioxide emission and at the same time maximizing the quality of project and its plan robustness. In this paper, study construction project scheduling considering a discrete trade-off between time, cost, quality,...

Living organisms can perform computations through various mechanisms. Understanding the limitations of these computations is not only of practical relevance (for example in the context of synthetic biology) but will most of all provide new insights into the design principles of living systems. This thesis investigates the conditions under which genes can perform logical computations and how thi...

In most inventory models it is assumed that the parameters of the model do not vary with time, and that the payment of orders from the retailer to the supplier is made immediately up on the receipt of these orders. Some suppliers, however, allow a certain fixed period to settle payment accounts. During this fixed period no interest is charged by the supplier, but beyond that period an interest,...