We introduce the frugal foraging model in which a forager performs a discrete-time random walk on a lattice in which each site initially contains S food units. The forager metabolizes one unit of food at each step and starves to death when it last ate S steps in the past. Whenever the forager eats, it consumes all food at its current site and this site remains empty forever (no food replenishme...

This article develops a supply chain coordination model with a single-vendor and a single-buyer. The vendor manufactures the product in lots and delivers to the buyer in equal shipments. However, the vendor’s production process is not perfectly reliable. During a production run, the process may shift from an in-control state to an out-ofcontrol state at any random time and produces some defecti...

The short lifetime of water on Venus suggests t ha t the water abundance is in a near steady-state balance between loss by escape and replenishment by infall. In addition, the observed deuterium-to-hydrogen ratio on Venus is consistent with a steady state and does not necessarily imply a past water excess. We present results of a model incorporating a stochastic cometary source and nonthermal e...

This paper addresses the single-item, non-stationary stochastic demand inventory control problem under the nonstationary (R,S) policy. In non-stationary (R,S) policies two sets of control parameters—the review intervals, which are not necessarily equal, and the order-up-to-levels for replenishment periods—are fixed at the beginning of the planning horizon to minimize the expected total cost. It...

T his study analyzes optimal replenishment policies that minimize expected discounted cost of multi-product stochastic inventory systems. The distinguishing feature of the multi-product inventory system that we analyze is the existence of correlated demand and joint-replenishment costs across multiple products. Our objective is to understand the structure of the optimal policy and use this stru...