The sewer layout in flat areas significantly influences the construction and operational costs as well as reliability of the network performance. To find an optimum design of sewer networks for flat areas, this study presents a multi-objective optimization problem with the objective functions of 1- the cost and 2- the reliability. The reliability criterion is defined as the effect of a clogging...

Lot-sizing is one of the many issues arising in the context of production planning. Its main objective is to determine the timing and level of production so as to reach the best possible trade-off between minimizing setup and inventory holding costs and satisfying customer demand. When a limited production capacity and a deterministic time-varying demand rate are assumed, lot-sizing leads to th...

We consider a capacitated production-inventory problem in both discreteand continuous-time, stationary settings. In the discretetime setting we analyze the infinite horizon capacitated dynamic lot-sizing problem, find the optimal solution and characterize its properties. For the continuous-time setting we formulate a new problem, which we claim to be an appropriate counterpart of the above disc...

An important special case of the economic lot-sizing problem is the one in which there are no speculative motives to hold inventory, i. e., the marginal cost of ]n'oducing one unit m some period plus the cost of holding it until some future period is at least the marginal production cost in the latter period. It is already known that this special case can be solved in linear time. In this paper...

e introduce a profit maximization version of the well-known Wagner-Whitin model for the deterministic uncapacitated single-item lot-sizing problem with lost sales. Demand cannot be backlogged, but it does not have to be satisfied, either. Costs and selling prices are assumed to be time-variant, differentiating our model from previous models with lost sales. Production quantities and levels of l...

We present lot-sizing heuristics that are both e cient and stable for the dynamic lot-sizing problem(DLSP) with constant or variable unit costs, including setup, inventory holding and production costs. These heuristics are myopic variants of the forward Wagner-Whitin algorithm with rolling horizons. Large scale computational experiments show that these heuristics considerably outperform other w...

Dynamic lot sizing problem is one of the significant problem in industrial units and it has been considered by many researchers. Considering the quantity discount in purchasing cost is one of the important and practical assumptions in the field of inventory control models and it has been less focused in terms of stochastic version of dynamic lot sizing problem. In this paper, stochastic dynamic...

Software companies exploit data about completed projects to estimate the development effort required for new projects. Software size is one of the most important information used to this end. However, different methods for sizing software exist and companies may require to migrate to a new method at a certain point. In this case, in order to exploit historical data they need to resize the past ...

Simulation is generally used to study non-deterministic problems in industry. When a simulation process finds the solution to an NP-hard problem, its efficiency is lowered, and computational costs increase. This paper proposes a stochastic dynamic lot-sizing problem with asymmetric deteriorating commodity, in which the optimal unit cost of material and unit holding cost would be determined. Thi...