this paper presents a k- turbulence model for simulation of steady current and itsinduced vortex shedding caused by the presence of an offshore pipeline. performance of the modelaround a circular cylinder above a wall with gap to diameter ratios of 0.1, 0.35 and 0.5 underdifferent flow regimes with reynolds numbers of 1500, 2500 and 7000 is studied. the flow field iscomputed with solving the re...

In this paper a one-machine scheduling model is analysed where n diierent jobs are classiied into K groups depending on which additional resource they require. The changeover time from one job to another consists of the removal or the setup time of the two jobs and is sequence-dependent in the sense that the changeover time is determined by whether or not the two jobs belong to the same group. ...

Revising the master production schedule (MPS) in a rolling planning horizon environment to improve plant performance is critical in process industries with sequence dependent changeovers. Plant performance is defined in terms of process changeover time, total shortages, and finished goods inventory. Two heuristics for revising the MPS are introduced and tested against a rolling horizon MPS that...

Abstract A hybrid Potts model where a random concentration p of the spins assume q 0 states and 1 − > is introduced. It known that when system homogeneous, with an integer spin number or , it undergoes second first order transition, respectively. argued there * such transition nature changed at *. This idea demonstrated analytically by simulations for two different types interaction: usual s...

Purpose This paper presents Quick Changeover Design (QCD), which is a structured methodological approach for Original Equipment Manufacturers to drive and support the design of machines in terms rapid changeover capability. Design/methodology/approach To improve performance set up time, QCD addresses machine from single-minute digit exchange die (SMED). Although conceived aid completely new mac...