نوع مقاله : مقاله پژوهشی

نویسندگان

گروه مهندسی صنایع، دانشکده مهندسی، دانشگاه کاشان، کاشان، ایران.

10.22105/dmor.2021.280972.1362

چکیده

هدف: مدل کلاسیک مقدار سفارش اقتصادی چندین دهه قبل برای کاهش هزینه‌های موجودی ارایه شد و از ان زمان تاکنون به‌طور گسترده در زمینه‌های مختلف کنترل موجودی مورداستفاده قرارگرفته است. در سال‌های اخیر محققان جنبه‌های گوناگون مدل EOQ را توسعه داده‌اند؛ زیرا مدل کلاسیک EOQ بسیاری از پارامترهای مهم در دنیای واقعی را در نظر نمی‌گیرد. هدف در این مقاله، توسعه­ی مدل کلاسیک EOQ در راستای عملیاتی و واقعی کردن مفروضات در فضای سفارش‌ها هم­زمان و با اقلام کیفیت نامطلوب است.
روش‌شناسی پژوهش: در این تحقیق یک مدل­سازی ریاضی برای سیستم موجودی کالای معیوب و همچنین الزام سفارش هم‌زمان توسعه داده می‌شود، سپس مدل ریاضی با روش تحلیلی حل می‌شود و اعتبارسنجی مدل با حذف مفروضات ارایه شده و تبدیل مدل فعلی را به مدل کلاسیک و درنهایت یک مثال عددی به همراه تحلیل نتایج ان ارایه می‌گردد.
یافتهها: نتایج نشان می ­دهد که تغییر نرخ غربالگری می‌تواند تاثیر به نسبت زیادی بر کاهش یا افزایش هزینه‌ها داشته باشد، این تاثیر هزینه ناشی از هزینه نگه‌داری اقلام با کیفیت نامطلوب تا انتهای دوره بازرسی است. هرچه عملیات غربالگری سریع‌تر انجام شود و اقلام معیوب سریع‌تر از سیستم خارج شوند، این هزینه‌ی تحمیل‌شده کمتر می‌شود.
اصالت/ارزش‌افزوده علمی: در مدل­ های کلاسیک فرض شده است اقلام باکیفیت مناسب سفارش داده می‌شوند. درحالی‌که در واقعیت به علت کیفیت ناپایدار فرایند تولید، حمل‌ونقل نامناسب، فسادپذیری یا دیگر فاکتورها، وجود اقلام معیوب امری اجتناب‌ناپذیر است. در سیستم موجودی  EOQ پیشنهادی این اقلام به کمک بازرسی %100 از محموله جداسازی شده‌ و سپس این اقلام جداسازی شده در قالب یک بسته باقیمت تخفیف یافته به فروش می‌رسد. همچنین به‌منظور کاهش هزینه‌‌‌های ثابت سفارش دهی و حمل‌ونقل، از سیاست دوره سفارش دهی هم‌زمان برای تمام دسته محصولات استفاده‌شده است که کارایی بالایی در کاهش هزینه ­ها دارد.

کلیدواژه‌ها

عنوان مقاله [English]

Developing a Multi-Product Economic Order Quantity Model with Necessary Simultaneous Orders for Imperfect Quality Items

نویسندگان [English]

  • Pegah Farhangian
  • Hadi Mokhtari

Department of Industrial Engineering, Faculty of Engineering, University of Kashan, Kashan, Iran.

چکیده [English]

Purpose: The classic model of economic order quantity was introduced several decades ago to reduce inventory costs in companies and has since been widely used in various areas of inventory control. In recent years, researchers have developed various aspects of the EOQ model; Because the classic EOQ model does not take into account many important parameters in the real world. The purpose of this paper is to develop a classic EOQ model in order to operationalize and realize the assumptions in the space of simultaneous orders with imperfect quality items.
Methodology: In this research, a mathematical modeling is developed for the imperfect inventory system as well as the simultaneous ordering requirement. Finally, a numerical example is provided along with the analysis of the results.
Findings: The results show that changing the screening rate can have a significant effect on reducing or increasing costs. This cost effect is due to the cost of maintaining items of poor quality until the end of the inspection period. The faster the screening operation and the faster the defective items are removed from the system, the lower the cost.
Originality/Value: In classic models, it is assumed that items of appropriate quality are ordered. In fact, due to the unstable quality of the production process, improper transportation, corruption or other factors, the presence of defective items is inevitable. In the proposed EOQ inventory system, these items are separated by 100% inspection of the consignment, and then these isolated items are sold in a package at a discounted price. Also, in order to reduce the fixed costs of ordering and shipping, the policy of simultaneous ordering has been used for all product categories, which has a high efficiency in reducing costs.

کلیدواژه‌ها [English]

  • Imperfect quality items
  • 100% inspection
  • Multiple products
  • Simultaneous ordering
  • Inventory control
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