patients and methods this retrospective cohort study included 405 renal transplant patients from kerman university of medical sciences hospital, kerman, iran from 2004 to 2010. kaplan-meier method was used to estimate survival rates of patients, and time-dependent cox regression was used to examine the effect of allograft failure on patient survival. results during 4.06 years (median) of follow...

A deterministic inventory model for infinite time-horizon incorporating inventory level-dependent demand rate, deterioration begins after a certain time, partial backlogging and decrease in demand is developed. The salient feature of the developed model is the introduction of the concept of fractional decrease in demand due to ageing of inventory. Demand at any instant depends linearly on the ...

This paper considers a time dependent(the travel time is not constant throughout the day) pollution routing problem (TDPRP), which aids the decision makers in minimizing travel time, toll cost and emitted pollution cost.  In complexity of urban areas most of the time one point is accessible from another with more than one edge. In contrast to previous TDPRP models, which are designed with only ...

Pistachio butter (semi solid paste), which is made from roasted pistachio kernels, is an appropriate alternative to work on because of its high nutritional and economical values. In this study, timedependent flow properties of pistachio butter were determined at two different temperatures (25˚C and 45˚C) for five different formulations (with different levels of emulsifying agents). Forward a...

This study proposes a new multi-item inventory model with hybrid cost parameters under a fuzzy-stochastic constraint and permissible delay in payment. The price and marketing expenditure dependent stochastic demand and the demand dependent the unit production cost are considered. Shortages are allowed and partially backordered. The main objective of this paper is to determine selling price, mar...

Article history: Received March 18, 2015 Accepted April 16 2015 Available online May 14 2015 In this paper, a deterministic inventory model with depletion rate dependent holding cost is developed. The demand rate is a power function of the on-hand inventory behind to a certain stock level, at which the demand rate becomes a constant. Shortages are allowed and partially backlogged with the funct...

a r t i c l e i n f o Economic production quantity (EPQ) is the quantity of a product that should be manufactured in a single batch so as to minimize the total cost. In classical model EPQ only applies where the demand for a product and production rate is constant over the year. But in reality these parameters vary with time in different scenarios. In this paper we have considered a production ...