Job scheduling has always been a challenging task in modern manufacturing and the most real life scheduling problems which involves multi-criteria and multi-machine environments. In this research our direction is largely motivated by the adoption of the Just-In-Time (JIT) philosophy in parallel machines system, where processing times of jobs are controllable. The goal of this paper is to minimi...

Wedescribe a polynomial-size conic quadratic reformulation for amachine-job assignment problemwith separable convex cost. Because the conic strengthening is based only on the objective of the problem, it can also be applied to other problems with similar cost functions. Computational results demonstrate the effectiveness of the conic reformulation. © 2009 Elsevier B.V. All rights reserved.

In this study, we determine the upper and lower bounds for the processing time of each job under controllable machining conditions. The proposed bounding scheme is used to find a set of discrete efficient points on the efficient frontier for a bi-criteria scheduling problem on a single CNC machine. We have two objectives; minimizing the manufacturing cost (comprised of machining and tooling cos...

TWO-MACHINE FLOWSHOP SCHEDULING WITH FLEXIBLE OPERATIONS AND CONTROLLABLE PROCESSING TIMES Zeynep Uruk M.S. in Industrial Engineering Advisor: Prof. Dr. Selim Aktürk Co-Advisor: Asst. Prof. Dr. Hakan Gültekin August, 2011 In this study, we consider a two-machine flowshop scheduling problem with identical jobs. Each of these jobs has three operations, where the first operation must be performed ...

This paper considers a project scheduling environment in which the activities of the project network are partitioned among a set of agents. Activity durations are controllable, i.e., every agent is allowed to shorten the duration of its activities, incurring a crashing cost. If the project makespan is reduced with respect to its normal value, a reward is offered to the agents and each agent rec...

We consider a single-stage manufacturing system where the physical state of each job is characterized by timedriven dynamics and its temporal state by event-driven dynamics. Extending an earlier analysis of a deterministic model for this system, we study a stochastic model where there are controllable parameters that affect the service processing speed. When job arrivals are represented through...

Traditional machining economics looks into the optimal set of machining conditions under which the production cost or time per part is minimized. No due dates are included in the consideration. Job sequencing searches for the optimal order of jobs so that lateness and/or earliness is minimized. The optimization assumes that processing times are fixed. In practice, processing times are variable ...

We consider a single-machine scheduling problem in which the job processing times are controllable or compressible. The performance criteria are the compression cost and the number of tardy jobs. For the problem where no tardy jobs are allowed and the objective is to minimize the total compression cost, we present a strongly polynomial time algorithm. For the problem to construct the trade-off ...

The focus of this study is a robot centered cell consisting of m computer numerical control (CNC) machines producing identical parts. Two pure cycles are singled out and further investigated as prominent cycles in minimizing the cycle time. It has been shown that these two cycles jointly dominate the rest of the pure cycles for a wide range of processing time values. For the remaining region, t...