In this paper, we present an inventory pooling model for spare units of critical systems that serve multi-companies. Companies located in the same geographical area can benefit from a coalition to share the storage cost of such spare units, which may be stored as one unit at only one company’s location. In our model, we combine the storage cost, replacement costs and downtime cost into a unifie...

Several recent experiments on DNA-damage-induced signaling networks in mammalian cells have shown interesting dynamics in p53 protein expression during the repair cycle. Pulses of p53 are produced, whose frequency and amplitude are fairly independent of the amount of damage, but the probability of a cell exhibiting this pulsatile behavior increases with damage. This phenomenon has been describe...

Spare parts are often associated with intermittent demand patterns that render their forecasting a challenging task. Forecasting of spare has been researched through both parametric and non-parametric approaches. However, little contributed in this area from Bayesian perspective, most such research is built around the Poisson distributional assumption. distribution known to have certain limitat...

This paper studies spare part transshipments between two service part facilities whose demands are correlated. Transshipments are used to reduce severity of part stock outs. Facilities are run by an inventory manager (IM) who minimizes replenishment, transshipment, and inventory costs. We show that the optimal transshipment policy is an inventory hold-back type; if the part inventory at a facil...

We consider a single warehouse where spare parts of multiple stock-keeping units are kept on stock to serve customers with (close-to-)identical machines. Customers are divided into multiple customer classes, and a target aggregate fill rate is set per class. In order to get differentiated service levels, critical level policies are assumed. We formulate a multi-item, single-stage spare parts in...

Compressed air energy storage (CAES) is a commercial, utility-scale technology that provides long-duration energy storage with fast ramp rates and good part-load operation. It is a promising storage technology for balancing the large-scale penetration of renewable energies, such as wind and solar power, into electric grids. This study proposes a CAES-CC system, which is based on a conventional ...

Classical spare parts inventory models assume that the same vintage of technology will be utilized throughout the planning horizon. However, replacement often occurs in the form of a new technology. A consequence of such replacements is the rendering of existing spare parts inventories obsolete and the necessity to purchase a new set. This paper aims to study the impact of spare parts inventory...

In this paper we describe G/G/R+s multi- repairmen machining system with balking. The system consists of M operating machines, S spare machines, R permanent and s additional repairmen. Assuming the discrete flow of machines by continuous one, the diffusion approximation technique for the machine repair system has developed. The system will be in normal working mode if there is M operating machi...

Communicating Applied Mathematics is a writingand speaking-intensive graduate course at North Carolina State University. The purpose of this article is to provide a brief description of the course objectives and the assignments. Parts A–D of of this article represent the class projects and illustrate the outcome of the course: • The Evolution of an Optimization Test Problem: From Motivation to ...