نوع مقاله : مقاله پژوهشی
نویسندگان
1 استادیار، دانشگاه کردستان.
2 دانش‌آموخته کارشناسی ارشد، دانشگاه کردستان.
چکیده
کاهش هزینه‌های مرتبط با موجودی از مهم‌ترین استراتژیهای هر بنگاه اقتصادی برای بقا و سوددهی در شرایط رقابتی امروزی است. در این راستا مدلهای موجودی کلاسیک برای کاهش این هزینهها مطرح شده‌اند؛ اما مدلهای کلاسیک در کنار مزایای فراوان دارای فرضیه‌های محدودکننده‌ای هستند. در این پژوهش، یک زنجیره سه‌سطحی لجستیکی شامل یک تولیدکننده، یک توزیع‌کننده و یک خردهفروش در نظر گرفته می‌شود و مسئله بهینه‌سازی مدل موجودی برای توزیع‌کننده موردبررسی قرار میگیرد. در مسئله موردنظر، توزیع‌کننده محصولات موردنیاز خود را از تولیدکننده درخواست می‌کند؛ اما به علت عدم‌امکان ارسال محصولات درخواستی هر دوره به‌صورت یکجا، تولیدکننده محصولات را به‌صورت گسسته در چند مرحله ارسال می‌کند؛ به‌عبارت‌دیگر از استراتژی دریافت چندگانه استفاده می‌شود؛ همچنین تقاضای خردهفروش گسسته بوده و برابر مقدار ثابتی در فاصلههای زمانی برابر است. در چنین حالتی، توزیع‌کننده در نظر دارد مقدار بهینه هر بار سفارش و مقدار بهینه ارسالی هر مرحله تولیدکننده را به‌گونه‌ای تعیین کند که هزینه‌های سیستم حداقل شود. درنهایت با بیان یک مثال عددی مسئله پیشنهادی بررسی و تحلیل شده و نتایج با مدل کلاسیک موجودی مقایسه می‌شود. نتایج نشان می‌دهد با افزایش هزینه‌های نگهداری و سفارش‌دهی، مدل پیشنهادی دارای کارایی بهتری است.
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
Economic Order Quantity with Discrete Demand and Delivery Orders
نویسندگان [English]
- Heibatolah Sadeghi 1
- Anwar Mahmoodi 1
- Zahra Rajabi 2
1 Assistant Professor, University of Kurdistan.
2 Graduated Master, University of Kurdistan.
چکیده [English]
Reducing inventory costs is among the essential strategies for survival and profitability in today’s competitive environment. Classical inventory models have been developed to minimize inventory costs. However, they have several limiting assumptions. In this study, a three-level logistic chain consisting of a manufacturer, a distributor, and a retailer is considered. The problem of optimizing the inventory model for the distributor is examined. The distributor orders the products from the manufacturer. However, the manufacturer does not simultaneously deliver the total order and sends them in several discrete instances. In other words, it employs the multi-delivery strategy. Furthermore, the retailer’s demand is discrete and equal to a fixed amount at each equal interval of time. The distributor aims to determine the optimal order quantity and the optimal plan of receiving orders to minimize the total costs. Finally, the proposed problem is analyzed in a numerical example, and the results are compared with the classical inventory model. The results show that the proposed model has better performance with increasing holding and fixed ordering costs.
کلیدواژه‌ها [English]
- Discrete Delivery Orders
- Discrete Demand
- Inventory Control
- Optimization
- Multi Delivery
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