Modification the Harris-Wilson's model of managment by Reserves

В статті розглянуто проблемні питання щодо застосування на практиці моделі оптимального розміру замовлення Харріса-Уілсона та запропоновані шляхи подолання обмежень, пов’язаних з умовами її використання. В статье рассмотрены проблемные вопросы применения на практике модели оптимального размера заказа Харриса-Уилсона и предложены пути преодоления ограничений, связанных с условиями её использования. The article deals with issues concerning the application in practice model of optimalorder size Harris-Wilson and proposed ways of overcoming the limitationsassociated with the conditions of its use

Model Economic Order Quantity untuk Barang yang Mengalami Pertumbuhan dengan Kualitas Tidak Sempurna dan Shortage

Model Economic Order Quantity (EOQ) merupakan model yang digunakan untuk mengelola sistem persediaan agar meminimalkan total biaya yang dikeluarkan. Model EOQ untuk barang yang mengalami pertumbuhan digunakan ketika barang yang disimpan memiliki kemampuan untuk bertumbuh selama siklus pengisian seperti hewan ternak, ikan, dan unggas. Akan tetapi barang yang mengalami pertumbuhan tidak selamanya berkualitas sempurna karena harus mengikuti standar kesehatan. Sehingga, persediaan yang ada akan berkurang dan menyebabkan permintaan tidak terpenuhi. Dengan memperbolehkan terjadinya kekurangan dapat mengurangi biaya yang dikeluarkan. Berdasarkan hal tersebut, Tugas Akhir ini membahas mengenai model Economic Order Quantity (EOQ) untuk barang yang mengalami pertumbuhan dengan kualitas tidak sempurna dan shortage. Tujuan dari model ini ialah meminimalkan total biaya yang dikeluarkan. Sehingga, berdasarkan pengaplikasian model pada data yang diambil dari supplier ayam potong milik ibu Nur’Aini diperoleh total biaya yang dikeluarkan ialah sebesar Rp. 106.926.950 dalam satu siklus atau dapat dikatakan lebih kecil 4,8% dari kebijakan toko saat ini

A Shared Information-Based Petri Net Model for Service Parts Planning

A considerable amount of electronic products are returned after sales, especially in such an economic downturn situation. After repair and refurbishment, the used products can be returned into the markets which fulfill the forward supply chains into a close loop. In this paper, we consider the service parts planning in the beginning of product rolling plan together with the sales through quantities to minimize the inventory level in the period of product lifecycle. A Petri Net is used to model a simple closed-loop supply chain with shared sales information. PUSH and PULL inventory policies are used in this research. Finally, it is investigated how a third party service provider uses this mechanism to improve the accuracy of inventory planning

Функциональное представление модели Харриса-Уилсона

The task of calculating the optimal delivery volume is central to the inventory management policy. The simplest Harris-Wilson model, largely familiar in the scientific and educational literature on logistics in computational and graphical forms, has been us ed for more than 100 years for the solution of this task in economic practice. This paper proposes a functional representation of this model

Bundling And Small Business Operations

The purpose of this paper is to develop and test a model for managing the inventory for a small, student managed food service business.  The Hazell Nut Café offers six coffees, six flavors of ice cream, four teas, hot chocolate, assorted pastries, bottled water, vitamin water, and four other types of cold beverages.  The purveyors for the all supplies, with the exception of dairy products, have on-call deliveries, but pre-set minimums for order quantities.  The dairy company requires a minimum weekly delivery.  After nearly one year of operation, the café’s student-managers are still developing an inventory management system.  The model developed here seeks to provide an easy to understand solution to the supply chain problems encountered by a small business such as the Hazell Nut Café

Learning by Gaming: Supply Chain Management

Today\u27s third level students are of a virtual generation, where online interactive multi-player games, virtual reality and simulations are a part of everyday life, making gaming and simulation a very important catalyst in the learning process. Teaching methods have to be more innovative to help students understand the complexity of decisions within dynamic supply chain environment. Interactive simulation games have the potential to be an efficient and enjoyable means of learning. A serious interactive business game, Automobile Supply Chain Management Game (AUSUM), has been introduced in this paper. Using theories learnt in class as a knowledge base, participants have to develop effective supply chain partnership strategy to enhance their supply chain networks. Deploying the game over the web encourages student interaction and group work. Most importantly the game will enable students to fundamentally grasp the impact of strategic decisions on other parts and players of the supply chain network

NEXT STEP in Cost-based Sustainable Production Development - Cases from different Production Operations

This article discusses the NEXT STEP (beyond Lean production philosophy) and its relation to Sustainable Production Development. One of the most important factors affecting long-term sustainability is the degree to which resource-efficient production can be achieved. From this standpoint, Lean Production is similar to Sustainable Production. The research reported on here suggests there to be no contradictions between having an efficient production process and this process being sustainable from a long-term perspective. Various production-cost models that can be used for evaluating different development scenarios with the aim of achieving resource efficient production in a wide variety of situations are discussed. The production cost models taken up deal with the following: 1) general losses in connection with downtimes, rejection rates and set-up times, in particular, 2) the degree of utilization of a production system 3) optimization of batch size with regard to setup times and inventory costs, 4) optimization of the manpower within a given production sector and 5) achievement of an optimum level of automation. The production cost models presented are applied to production elements of different types: machining operations, automated production lines for manufacturing sheet-metal products, and semi-manual assembly. This is done to exemplify the development steps necessary for achieving long-term sustainability in connection with different production scenarios

Shop Floor Lot-sizing and Scheduling with a Two-stage Stochastic Programming Model Considering Uncertain Demand and Workforce Efficiency

Efficient and flexible production planning is necessary for the manufacturing industry to stay competitive in today’s global market. Shop floor lot-sizing and scheduling is one of the most challenging and rewarding subjects for the management. In this study, a two-stage stochastic programming model is proposed to solve a single-machine, multi-product shop floor lot-sizing and scheduling problem. Two sources of uncertainties are considered simultaneously: product demand from the market, and workforce efficiency, which is the major contribution of this study. The workforce efficiency affects the system productivity, and we propose different distributions to model its uncertainty with insufficient information.The model aims to determine optimal lot sizes and the production sequence that minimizes expected total system costs over the planning horizon, including setup, inventory, and production costs. A case study is performed on a supply chain producing brake equipment in the automotive industry. The numerical results illustrate the usefulness of the stochastic model under volatile environment, and the solution quality is analyzed

A novel cross-docking EOQ-based model to optimize a multi-item multi-supplier multi-retailer inventory management system

Nowadays, the retail industry accounts for a large share of the world’s economy. Cross-docking is one of the most effective and smart inventory management systems used by retail companies to respond to demands efficiently. In this study, the aim is to develop a novel cross-docking EOQ-based model for a retail company. By considering a two-stage inventory procurement process, a new multi-item, multi-supplier, multi-retailer EOQ model is developed to minimize the total inventory costs. In the first stage, the required items are received from suppliers and are held in a central warehouse. In the second stage, these items are delivered to several retail stores. The total inventory costs include four main parts, i.e., holding costs at the central warehouse, holding costs at the retail stores, fixed ordering costs from the suppliers, and fixed ordering costs from the central warehouse. The optimal inventory policy is obtained by analyzing extrema, and a numerical example is used to confirm the efficiency of the proposed model. Based on the obtained results, it is evident that the proposed model produces the optimal policy for the cross-docking system. Furthermore, the model enables managers to analyze the effects of key factors on the costs of the system. Based on the obtained results, the annual demand of each retailer, the ordering cost by the central warehouse, the ordering cost at each retail store, and the holding cost at each retail store have a direct impact on the optimal cost. Furthermore, it is not possible to describe the effects of the holding cost at the central warehouse on the optimal cost of the system generally