A two-component production inventory-assembly system

Abstract

The paper considers a two-component continuous review inventory system where one of two components is produced by the organisation and the other is supplied by an outside supplier. The two components are assembled into an end product. There are two different product types. Demand occurs according to a Poisson process for each of the product types. It is assumed that product 1 is produced and its production time is arbitrarily distributed. Production is interrupted when the inventory level of product 1 reaches its maximum level. Replenishment of product 2 is done according to an adjustable reorder policy, and the lead-time follows an exponential distribution. Identifying the stochastic process as a semi-regenerative process, steady-state measures such as mean stationary rate of the number of demands lost, mean number of demands satisfied, mean number of replenishments made, are found. The total unutilised capacity of the production system is found, and a cost analysis is also studied. A numerical example is provided to illustrate the results obtained.

‘n Voorraadsisteem wat kontinu hersien word vir twee verskillende komponenttipes word bestudeer. Die komponente word gebruik vir twee verskillende produktipes. Die verbruik van elke produktipe word beskryf deur ‘n Poissonverdeling. Die produksietyd vir produktipe 1 is arbitrêr verdeel. Sodra die voorraadpeil van produk 1 die maksimum bereik, word produksie gestaak. Aanvulling van produktipe 2 word gedoen volgens ‘n verstelbare herbestelbeleid met eksponensiele leityd. Identifisering van die stogastiese proses as half-regenererend lei vervolgens tot bepaling van gestadigde maatstawe soos gemiddelde aantal verlore eenhede, gemiddelde bevredigde vraag, en gemiddelde aantal aanvullings. Die totale ledigheid van die sisteem word bepaal en die gepaardgaande koste bereken. ‘n Syfervoorbeeld word voorgehou om die resultate te bevestig.