Practical inventory settings often include multiple generations of the same product on hand. New products often arrive before old stock is exhausted, but most inventory models do not account for this. Such a setting gives rise to the possibility of inter-generational substitution between products. We study a retailer that stocks two product generations and we show that from a cost perspective the retailer is better off stocking only one generation. We proceed with a profit scheme and develop a price-setting profit maximization model, proving that in one and two generation profit models there exists a unique solution. We use the profit model to show that there are cases where it is more profitable to stock two generations. We discuss utility and preference extensions to the profit model and present the general n-product case.

Inventory management is today seen as more competitive oriented, process oriented and better integrated into the companies than before. But still do several companies run their inventories according a traditional approach. There is therefore a need for some companies to evaluate their inventory management and adapt the new view. There is also a need to adjust for increased focus on sustainability, previous research calls for strategies and tools that include sustainable parameters without lowering the profitability. The purpose with this study is to assess inventory management principles and purchasing routines related to the acquisition of packaging material in a process industry. The study aims to develop a framework for decision makers in inventory management. This framework will be the basis for a support tool incorporating a relatively simple and easy-to-use user interface. This master thesis is performed as a case study research and uses several data collection methods, such as a literature review, observations, and interviews. The findings from the data collection is used to evaluate which impact inventory management has on a company’s profitability, and which basic parameters that could be included in the support tool. The empirical findings show that Barilla Sweden’s current inventory management match the traditional approach, but also that they strive to become more competitive and process oriented in their management of inventories. There is however some constraints in their working strategy that prevents them from taking the next step. Comparison between Barilla Sweden’s current order size and an economical order quantity (EOQ) and just-in-time (JIT) approach is made. The comparison shows that Barilla Sweden has money to save and warehouse space to release with changed order quantities. Adapting a new inventory management approach require review of uncertainties, such as delivery accuracy and forecast changes. It is also necessary to evaluate supplier relations and internal working strategies. The effect of these parameters on inventory management can be noticed in the support tool. The tool compares total costs, average stock, tied capital, and environmental and social consequences between the EOQ model and JIT. The support tool visualizes drawbacks and benefits with different order sizes and has an easy-to-use interface.

Practical inventory settings often include multiple generations of the same product on hand. New products often arrive before old stock is exhausted, but most inventory models do not account for this. Such a setting gives rise to the possibility of inter-generational substitution between products. We study a retailer that stocks two product generations and we show that from a cost perspective the retailer is better off stocking only one generation. We proceed with a profit scheme and develop a price-setting profit maximization model, proving that in one and two generation profit models there exists a unique solution. We use the profit model to show that there are cases where it is more profitable to stock two generations. We discuss utility and preference extensions to the profit model and present the general n-product case.

This thesis is called "Stock Management in the Store". The main aim of the thesis is to determine the optimal size and composition of inventory assortment in the store. The thesis consists of two parts - theoretic and practic one. The first part was focused on stock management in the business unit. The selected store was characterized in the practical part. Subsequently, was selected five specific samples of goods selected assortment categories - meat products, dairy products, pasta and drinks. On these groups of products was accomplished optimization. This optimization was accomplished by analysis of selected products, Economic Order Quantity and Direct Product Profilitability.

The subject of this thesis is to propose a new inventory management system, that was found in particular company as one of the biggest shortages, which the company currently faces. The first part of thesis contains theoretical background focused on inventory management, expecially on function and types of supplies, ordering systems of supplies and on methods of their inventory. The second part focuses on the analysis of the current state in company processes. Following the theoretical part, there were suggested appropriate inventory management systems to simplify the work in warehousing and logistic, but also to bring economic benefits to the whole company. In addition to these proposals were included also possible solutions of less problematic processes.

Spare parts are, for many companies, a complex product to logistically handle. This is in part due to the varying characteristics and sporadic demand patterns of spare parts. Obstacles can often arise when companies utilize the same approach to their spare parts stock as they do with their general warehouse manufacturing inventory. By using the same approach, companies risk neglecting the widespread variation of the spare parts. With the help of established routines, a clear set of guidelines and factors, the chances of a successful handling of spare parts inventory is increased. The study is a qualitative case study with the purpose of identifying specific factors and to make recommendations of models for companies to take into account when evaluating and storing spare parts. Through unstructured/semi-structured interviews conducted with four case company employees, information was gathered which was used to assist in identifying these specific factors and models for companies. A theoretical frame of reference was produced through analyzing research articles and was compared to the compiled empirical data in an analysis. The departments within the case study based their work on single factor which were considered important for each specific department, without inter-departmental communication. The factors that were identified in the study include service, competitive advantage, tied up capital, size capacity, complexity, sales frequency and material. Four of these were considered to be a priority for the case company. The study showed that different models for spare parts management and outsourcing could be implemented in the case company. By integrating the different models for spare parts management and outsourcing, combined with communication, a new model has been proposed for handling the spare parts storage. / Reservdelar är för många företag en komplex produkt att hantera utifrån dess varierande egenskaper och sporadiska efterfrågemönster. Problematiken härstammar ofta från att många företag hanterar reservdelslager utifrån samma förutsättningar som dess allmänna lagerhantering, därigenom försummas reservdelarnas olika egenskaper. Förutbestämda riktlinjer och faktorer krävs vid hantering av reservdelar och en viktig komponent för att lyckas med detta är kommunikation. Arbetet är en kvalitativ fallstudie med syftet att ta fram faktorer och rekommendationer av modeller att ta hänsyn till vid värdering och lagerhantering av reservdelar. För att besvara syftet och frågeställningarna utfördes ostrukturerade/semistrukturerade intervjuer med fyra medarbetare på fallföretaget. En teoretisk referensram togs fram genom litteratursökningar som sedan ställdes i en jämförelse mot den sammanställda empirin i en analys. Studien visade att de olika avdelningarna på fallföretaget främst utgått från en enda faktor som ansetts vara viktig för den specifika avdelningen. Utifrån de framtagna faktorerna i studien; service, konkurrensfördel, kapitalbindning, fyllnadsgrad, komplexitet, försäljningsfrekvens och material, ansågs fyra av dessa vara av prioritet för fallföretaget. Studien visade att olika modeller för reservdelshantering och outsourcing skulle kunna implementeras på fallföretaget. Genom att integrera de olika modellerna för reservdelshantering och outsourcing, kombinerat med kommunikation, har en ny modell föreslagits för hantering av reservdelslager.

The master’s thesis deals with study of the supply management in production company Česká zbrojovka, a.s. The theoretical solutions deal with spheres needed for determination of optimal supply of the specified materials. On the basis of an analysis of the actual state of affairs, conducted ABC analysis (analysis and calculation of the optimal supply for specified materials) contains the proposals and methods for economic order quantity for other inventory. The outputs of my thesis are the methods of the dealing with optimal supplies and the proposal.

No description available.

Inom byggindustrin är det svårt att skapa standardiserade logistikprocesser eftersom det vid varje nytt bygge även skapas en ny organisation. Förutsättningarna skiljer sig även mellan olika byggen, vilket försvårar ett förbättringsarbete. Skanska Väg och Anläggning Norr fick under 2017 uppdraget att bygga om Vasaplan i centrala Umeå, och i september 2018 stod projektet klart. Ombyggnationen var i det stora hela ett mycket lyckat projekt, men efter färdigställandet av projektet har problem angående materialtillgång identifierats. Syftet med arbetet är att undersöka hur leveranser till en byggarbetsplats kan optimeras samt hurvida ett mellanlager kan underlätta hanteringen av leveranserna till byggarbetsplatsen. En jämförelse har gjorts där det har undersökts ifall det är mer lönsamt att använda sig av lagerhållning, eller endast av JIT-leveranser. Förhoppningen är att arbetet kan bidra till att Skanska i framtiden får ett mer standardiserat tillvägagångssätt vid planering av leveranser till byggarbetsplats av material som kräver liknande lagerhållning och transport som granithällar. För att lösa detta har två matematiska modeller använts; Anläggningslokaliseringsproblemet (ALP) samt en matematisk modell som optimerar placering av material på en lageryta. Två stycken produktionsflödesmodeller, JIT och EOQ, har även använts i beräkningarna. Resultatet från produktionsflödesmodellerna, JIT och EOQ, visar att JIT-leveranser med hjälp av en omlastningscentral alltid är den mest kostnadseffektiva lösningen då lageryta är en direkt kostnad för Skanska. I de fall lager inte är en direkt utgift för Skanska så rekommenderar den matematiska modellen för ALP en optimal användning av de lager som är tillgängliga. / For every new construction project, a new organisation is created. It is therefore a challenge for the construction industry to create standardized logistic processes. In addition, different construction projects have different traits, which results in further challenges for improvement efforts for the construction logistic processes. In 2017 Skanska Väg och Anläggning Norr did the reconstruction of Vasaplan in the central of Umeå, and in September 2018 the reconstruction project was done. The reconstruction was in its entirety a very successful project, however when the project was finished problems regarding material supply were identified. The aim of this paper is to analyze how deliveries to a construction site can be optimized and whether storage spaces can aid in the handling of deliveries to the construction site. A comparison has been made between storing material and using JIT-deliveries. The hope is to help Skanska in developing a more standardized approach when it comes to planning the deliveries of materials that has similar storage and transport conditions as the slabs of granite used. To solve this two mathematical models have been used; Facility location problem and a mathematical model that optimizes the placement of materials in a storage space. Two production flow models, JIT and EOQ, were also used when performing the calculations. The result from the production flow models, JIT and EOQ, show that JIT deliveries are always the most cost effective solution when storage space is a direct cost for Skanska, when used together with a logistics center. However, when storing is no extra expense for Skanska, the mathematical model for the Facility location problem suggests a optimal use of the storage spaces that are available.

Este é um trabalho teórico-empírico que visa principalmente verificar o estado da literatura científica no que diz respeito à consideração dos custos de financiamento da necessidade de capital de giro (NCG) aplicado em mercadorias (NCGp), especialmente em relação aos aprimoramentos do modelo do lote econômico de compras/produção (LEC/LEP). A revisão de literatura mostra diversos modelos aprimorados do LEC/LEP que usam as técnicas de valor presente líquido e fluxos de caixa descontados para considerar o custo do capital no tempo, mas, segundo diversos autores, a diferença entre o LEC original e o uso de tais técnicas é desprezível. Além do mais, o uso destas técnicas não significa que tais modelos tenham incorporado o custo do financiamento da NCGp. Alguns trabalhos, mais recentes, já trazem simulações que levam em consideração o NCGp, outros até já exibem a fórmula NCGp = Estoquesp+Clientesp+Fornecedoresp. Neste trabalho foram feitas 128.000 simulações estocásticas de um modelo dinâmico, de onde se extraíram as variáveis da DRE de cada membro de uma cadeia de suprimentos (CS) hipotética. Foi testada a hipótese de ser este modelo aprimorado, porque incorpora o custo do capital de giro empregado nas mercadorias, mais correto que o modelo que não o incorpora. Para fazer este teste, foi feita uma modelagem (em Excel R) de uma CS contendo dois fornecedores industriais, uma fábrica, um atacadista e um varejista. O modelo recebe como inputs as demandas agregadas do varejista nos dias de cada simulação, que são 360 dias. Os dados foram importados no software estatístico R e as variáveis de saída foram então analisadas nos diversos cenários, regimes e tipos de demanda. Os resultados da análise dos diferentes cenários mostram que é importante considerar os custos financeiros da NCGp. / This is a theoretical and empirical work that primarily aims to check the status of scientific literature with regard to the consideration of the costs of financing the working capital needs (WCN ) applied to goods (WCNp), especially in relation to improvements of economic order/- production quantity (EOQ/EPQ) models. The literature review shows several EOQ/EPQ enhanced models that use net present value and discounted cash flows techniques to consider the cost of capital over time; but according to several authors, the difference between the original EOQ model and with the use of such techniques is negligible. Moreover, the use of these techniques does not mean that such models have incorporated the cost of financing the WCNp. Some latest papers make simulations that consider the WCNp, others have even used the formula WCNp = Inventoriesp +Receivablesp +Payablesp. In this study we made 128,000 stochastic simulations of a dynamic model, from where the were obtained the result\'s variables for each member of a hypothetical supply chain(SC).We tested the hypothesis that this enhanced model, because it incorporates the cost of working capital employed in goods, is more correct than the model that does not. For this test, we made a model (in Excel R) of a CS containing two industrial suppliers, a factory, a wholesaler and a retailer. The model takes as inputs the aggregated demands of the retailer in the days of each simulation, which is 360 days. Data were imported into R statistical software and the output variables were then analyzed in different scenarios, regimes and types of demand. The results of the analysis of different scenarios showed that it is important to consider the financial costs of WCNp, maybe incorporating them into an enhanced EOQ/EPQ model.