background: to extract utility values of diabetic retinopathy on a perfect health and perfect vision scales for iranians with both types diabetes. methods: in this investigation, 150 untreated patients with diabetic retinopathy consecutively were examined and interviewed in farabi eye hospital, tehran, iran, a tertiary referral center in the iranian health care system. utility values based on p...

In this paper, an efficient multi-objective model is proposed to solve time-cost trade off problem considering cash flows. The proposed multi-objective meta-heuristic is based on Ant colony optimization and is called Non Dominated Archiving Ant Colony Optimization (NAACO). The significant feature of this work is consideration of uncertainties in time, cost and more importantly interest rate. A ...

This paper presents a multi-objective resource-constrained project scheduling problem with positive and negative cash flows. The net present value (NPV) maximization and making span minimization are this study objectives. And since this problem is considered as complex optimization in NP-Hard context, we present a mathematical model for the given problem and solve three evolutionary algorithms;...

this paper presents a multi-objective resource-constrained project scheduling problem with positive and negative cash flows. the net present value (npv) maximization and making span minimization are this study objectives. and since this problem is considered as complex optimization in np-hard context, we present a mathematical model for the given problem and solve three evolutionary algorithms;...

In common models of project time-cost trade-off, time value of money is not considered and often time-cost trade-off is performed without considering time value of money. In real world, pass of time causes decrease in money value. Therefore, taking into account the time value of money in time-cost trade-off problem makes this problem is becoming more and more realistic. In this paper, we study ...