Analiza porównawcza klasycznych modeli sterowania zapasami

• Autorzy: Jodejko A.

Warianty tytułu

EN

The comparative analysis of classic inventory control models

• Języki publikacji: PL

Abstrakty

PL

Celem artykułu jest analiza wyników, jakie uzyskać można przy jednakowej charakterystyce popytu i czasu realizacji dostaw przy zastosowaniu odmiennych modeli sterowania zapasami: (Q/ s), (S, t), (S, s). Rezultaty badania przedstawiają m.in. różne możliwości adaptacyjne poszczególnych modeli do losowych warunków działania przedsiębiorstwa oraz wyniki poszczególnych modeli z punktu widzenia wybranej funkcji celu.

EN

Various kinds of inventories are one of the basic ways to control the random character of economic processes. The inventory literature gives a great number of models which may be used in order to gain specified goals of an enterprise: financial or other results. When a company works in random conditions, the literature and the market practice propose effective inventory control models, which have an ability to adapt to existing situation. The most popular are models called: re-order point (Q,s) and re-order cycle (S,t) and their combinations. The question is -- which model one should choose and what results it will show? The aim of this paper is to analyze the effect of different inventory control models in such exemplary system, when the demand and lead time are the same. The models (Q,s), (S,t) and their combination (S,s) are examined. The investigation was made on the base of simulation experiments, separately for every inventory control model. The assumed demand had normal and exponential probability distribution and the lead time was constant, normally or exponentially distributed. Two types of outcomes were tested: the total inventory cost per unit time and the service level. The research allows stating that the same input data cause different results, depending on the inventory control model. The (S,s) model has the best ability to adapt to random conditions of the enterprise functioning. It produces higher service level than (Q,s) for almost all tested values of order quantity Q. The financial results of both models were comparable. The (Q,s) model is the policy whose parameters should be precisely selected. When the enterprise has to especially avoid inventory lack, it is better to apply (S,s) model. When speaking about lead time, the examination allows saying that constant lead time causes the lowest inventory lack probability. When lead time is exponentially distributed, it is much harder to reduce the inventory shortage risk than in other cases. That is why, when the enterprise has to take into account some safety restrictions, it should analyze lead time character while determining inventory policy. The total inventory cost of various models related to service level shows that the cost mainly depends on demand and lead time character and the kind of inventory control model has lesser meaning.

Słowa kluczowe

PL

sterowanie zapasami; zapasy; prawdopodobieństwo; zarządzanie łańcuchem dostaw; zarządzanie zapasami; polityka zaopatrzenia

EN

inventory control; inventories; probabilities; supply chain management; production control; kontrola techniczna

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Systems : journal of transdisciplinary systems science
• Rocznik: 2007
• Tom: Vol. 12, nr 2
• Strony: 79--89
• Opis fizyczny: Bibliogr. 13 poz.

Twórcy

autor

Jodejko A.

• Instytut Konstrukcji i Eksploatacji Maszyn Politechniki Wrocławskiej

Bibliografia

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