In today’s global and competitive markets selling products at competitive prices, coordination of supply chain configuration, and environmental and ecological consciousness and responsibility become important issues for all companies around the world. The price of products is affected by costs, one of which is inventory cost. Inventory does not give any added value to products but must be kept in order to fulfill the customer demand in time. Therefore, this cost must be kept at the minimum level. In order to reduce the amount of inventory across a supply chain, coordination of decisions among all players in the chain is necessary. Coordination is needed not only for a two-level supply chain involving a manufacturer and its customers, but also for a complex supply chain of multiple tiers involving many players. With increasing attention being placed to environmental and ecological consciousness and responsibility, companies are keen to have a reverse supply chain where used products are collected and usable components remanufactured and reused in production to minimize negative impacts on the environment, adding further complexity to decision making across a supply chain. To deal with the above issues, this thesis proposes and develops the mathematical models and solution methods for coordinating the production inventory system in a complex manufacturing supply chain involving reverse logistics and multiple products. The supply chain consists of tier-2 suppliers for raw materials, tier-1 suppliers for parts, a manufacturer who manufactures and assembles parts into finished products, distributors, retailers and a third party who collects the used products and returns usable parts to the system. The models consider a limited contract period among all players, capacity constraints in transportation units and stochastic demand. The solution methods for solving the models are proposed based on decentralized, semi-centralized and centralized decision making processes. Numerical examples are used by adopting data from the literature to demonstrate, test, analyse and discuss the models. The results show that centralised decision making process is the best way to coordinate all players in the supply chain which minimise total cost of the supply chain as a whole. The results also show that the selection of the length of limited horizon/ contract period will be one of the main factors which will determine the type of coordination (decentralised, centralised or semi-centralised) among all players in the supply chain. We also found that the models developed can be viewed as generalised models for multi-level supply chain by examining the models using systems of different tiers from the literature. We conclude that the models are insensitive to changes of input parameters since percentage changes of the supply chain’s total cost are less than percentage changes of input parameters for the scenarios studied.

Autor no autoriza el acceso a texto completo de su documento hasta el 04/12/2019. / Ingeniero Civil Industrial / El presente trabajo de memoria se desarrolló en la empresa Procter & Gamble, dentro el área de logística, específicamente en el marco del suministro de Desodorantes y Anti-Transpirantes producidos y distribuidos por la multinacional. El trabajo consta de un análisis cuantitativo del funcionamiento de una de las plantas productoras de los ya mencionados bienes, la cual alimenta parte de las cadenas de suministro de los mercados de Latinoamérica. A partir de este análisis se realiza un diagnóstico del desempeño de dicha planta en cuanto al manejo de inventarios y al nivel de servicio, todo respecto al producto terminado de la planta, además de un profundo estudio de la demanda, para analizar la capacidad de la planta en estudio a mediano/largo plazo. El objetivo principal de esta memoria es conseguir una mayor eficiencia en cuanto a los niveles de inventarios de producto terminado, sin ir en desmedro del nivel de servicio. Para esto, se realiza un levantamiento del proceso productivo de la planta, lo que permite generar un diagnóstico e identificar las oportunidades de mejora, en las cuales se basa la propuesta de solución, centrada en una reducción de los inventarios de seguridad de cada producto a través de una simulación computacional. Los resultados obtenidos apuntan a una reducción cercana al 9% en los niveles de inventarios de seguridad asociados a los productos originados en la planta, lo cual representa un ahorro estimado de los costos de almacenamiento cercano a los USD$450 mil anuales. Se concluye también sobre el horizonte para el cual la planta podría funcionar sin inconvenientes de capacidad en cada una de sus líneas productivas.

Supply Chain Management (SCM) aims to synchronize the requirements of customers with the flow of materials from suppliers, in order to satisfy the needs of the customers as costefficiently as possible. This has become a difficult task due to several developments in the market, such as increased competition, increased demand variability, increased product variety, increased amounts of customer-specific products, and shortening product life cycles. These developments, due in part to globalization, provide additional management challenges and new practices in which supply chains are designed and managed, and can eventually make the difference between companies staying competitive or not. The overall purpose of this thesis is to investigate how complexity and globalization affect supply chain design and operations. The main emphasis has been on producing descriptive results of the studied phenomenon. This research involves five case studies covering international transportation structures used in SCM, the selection of supply chain strategies in different business environments, and the role of information systems and technology in achieving the objective of SCM. In this thesis it has been concluded that in order to cope with increasingly complex and fragmented markets companies need more differentiated transportation structures, modes, and supply chains. Furthermore, to effectively manage this, information systems and advanced decision support tools are required. In addition, this thesis has shown that current taxonomies for supply chain strategy selection are too simplistic due to three major problems: they mediate that it is a question of choosing one supply chain strategy for the entire company, they regard markets as rather homogeneous, and they link each supply chain strategy to a specific business context. Instead, it has been concluded that in order to better satisfy differing customer needs in various markets it is increasingly necessary to develop a differentiated supply chain strategy by utilizing different manufacturing and delivery strategies concurrently. Thus, a need exists for new taxonomies for supply chain strategy selection which recognize that the markets are becoming more fragmented and complex, that customer preferences differ across customer/market segments, and that there is a need to differentiate the supply chain strategy. This thesis also highlights several requirements of a differentiated supply chain strategy. Firstly, extended supply chain collaboration is required, since a differentiated supply chain strategy will involve more supply chain partners than a traditional supply chain strategy. Secondly, there is a need for more transportation mode alternatives, particularly intermodal, both in supply and distribution operations, due to the fact that differentiation requires diversity. In this thesis, intermodal landbridge freight services are highlighted as one interesting avenue, which could potentially facilitate a more differentiated supply chain strategy. Thirdly, more integrated information systems are needed along with decision support tools. This study illustrates that agent based modeling appears to be an interesting method for developing realistic decision support tools in the context of complex supply chains. An interesting aspect for further research is to investigate how different manufacturing and delivery strategies can be used concurrently in international supply chains. Moreover, there are several requirements and opportunities of a differentiated supply chain strategy, and these have to be investigated further

The South African Construction Industry is one of the largest contributors to the gross domestic product of the country as well as to employment. It has, however, been experiencing significant challenges due to multifaceted factors. The main objective of this research was to identify the supply chain management constraints within the South African Construction Industry and how these can be overcome. This study is by nature descriptive and exploratory and contains qualitative elements. The problems were identified through a literature review, focused group discussions and interviews with major construction companies in South Africa. The findings also indicate that the main supply chain management constraints are to a greater extent internal and typical of supply chain methodologies and approaches. These constraints are among others the lack of coordination, collaboration and commitment between suppliers and clients within the supply chain, poor leadership in key areas of systems, design problems (many changes and inconsistent information), deficient internal and external communication and information transfer, inadequate management within the supply chain, mainly poor planning and control just to mention a few. A model based on supply chain system management as well as the Theory Of Constraints (TOC) has been developed that can be a useful tool to address the constraints in the construction sector. Originating from the study are applicable recommendations for the South African construction industry supply chains, covering key themes that have been articulated in the study, particularly benchmarking to the theory of constrains. Such recommendations include further research core components of supply chain such as, collaborations, logistics and how each of system components can be linked to performance of the supply chain management system.

Falsified and substandard drugs are classified as a global problem and continue to increase as manufacturing becomes globalized and the complexity of distribution systems expands. The falsified and substandard drugs come with major health risks and socioeconomic consequences. The pharmaceutical supply chain is handled by several parties, making it harder to detect when falsified and substandard drugs end up in distribution. Since the rise of the cryptocurrency bitcoin, blockchain technology has been recognized for its transparency and security. Previous research describes blockchain as a decentralized database structure that preserves a chronological chain of blocks where each block contains a registered valid network activity verified by consensus of the participants in the network. The purpose of this study is to create a broader understanding of how blockchain can improve the transparency and traceability of the pharmaceutical supply chain in order to reduce the incidence of falsified and substandard drugs. The study is based on a qualitative method in the form of five semi-structured interviews with representatives from the pharmaceutical industry and two blockchain companies. In the study's discussion section, the literature study is set against the collected empirical material. Two tables also illustrate how the pharmaceutical industry is working with traceability and what effects blockchain can provide a supply chain. Finally, the study notes that regulations on the pharmaceutical industry primarily control which database structure is implemented on the supply chain. It is also stated that blockchain has characteristics that can improve transparency and traceability of a supply chain, but the technology is to some extent limited mainly by its large need for capacity

Die Prozesse und Aktivitäten der petrochemischen Industrie bieten aufgrund ihrer Vielfalt und Komplexität meist ein großes Potenzial für Verbesserungen. In diesem Beitrag sollen anhand kurzer Fallbeispiele, die in Kooperation mit OMV entstanden sind, drei solcher Optimierungspotenziale beispielhaft aufgezeigt werden. Dabei wird der Fokus auf die Downstream-Logistik gelegt und die Distribution der raffinierten Endprodukte zu den Endkunden (Tankstellen) analysiert. Auf strategischer Planungsebene werden die optimalen Standorte von Tanklägem bestimmt und die ökonomische und ökologische Performance verschiedener Netzwerk-Designs verglichen. In einem Fallbeispiel zur taktischen Planung wird ein Optimierungsmodell zur Planung der Transportmengen in einem Distributionsnetzwerk mit stochastischer Nachfrage dargestellt. Die effiziente Tourenplanung von den Lkw zu den Tankstellen stellt schlussendlich ein operatives Planungsbeispiel dar.

Thesis: M. Eng. in Logistics, Massachusetts Institute of Technology, Supply Chain Management Program, 2016. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 52-53). / To be competitive, businesses must make supply network design decisions, but often with only limited information and under uncertain conditions. How can an organization understand trade-offs between supply network decisions, without relying on complex, black-box models that require extensive data collection and hidden assumptions? We apply approximation methods to estimate and compare total logistics cost of supply network designs under various business conditions, such as variations in demand, changing costs, and shifting production policies. The method is applied to the real-world example of XYZ Co, evaluating network design choices for a new, rapidly growing product category: fresh foods. The method is used to evaluate tradeoffs between five distinct network designs for supply of these highly perishable foods to XYZ Co stores from a sole regional supplier. The model provides insights to help understand tradeoffs and key cost drivers, thereby channeling subsequent, more intensive and time- consuming analysis. / by Cyril Khamsi and Veronica Stolear. / M. Eng. in Logistics

Thesis: M. Eng. in Logistics, Massachusetts Institute of Technology, Supply Chain Management Program, 2016. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 42-43). / This thesis analyzes the impact on prices and capacity of trucking industry due to the introduction of ELD mandate. This mandate requires truck drivers to record their working hours in a specified electronic device instead of a pen and paper method. This thesis utilizes the change in average truck driver working hours, cost of ELD equipment and distance from origin to destination of truck loads to determine the potential impact on trucking market. The models used provide an estimation of the impact on capacity and cost and the likelihood of impact on the economics of trucking industry. / by Chan How Law. / M. Eng. in Logistics

Thesis: M. Eng. in Logistics, Massachusetts Institute of Technology, Supply Chain Management Program, 2016. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 46-47). / Large pharmaceutical companies struggle to find innovative ways to reduce work-in-process inventory in their production facilities. In our research, we focus on the tradeoff between inventory and production capacity through investing in new facilities and equipment. This tradeoff will depend on the company's objectives and what it is willing to give up in return for reducing inventory. We found that increasing capacity to reduce work-in-process inventory by investing in new facilities is not always the most favorable approach in terms of net present value. However, for flexibility or lead-time improvements, it may make sense to proceed with the investment. We developed multiple scenarios considering the company's future plans to reduce inventory or grow. These scenarios provide insights into the factors that improve the attractiveness of the investments and those that do not. Our financial analysis along with the guidelines and procedures that we have developed help the sponsor company most effectively reach its goal to reduce its work in process inventory. / by Karim Kamareddine and Yihong Yao. / M. Eng. in Logistics

Thesis: M. Eng. in Logistics, Massachusetts Institute of Technology, Supply Chain Management Program, 2016. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 66-67). / Order-picking is an integral operation in warehouses and distribution centers (DC), consuming considerable operating resources and expenses. Numerous studies have attempted to optimize the efficiency and reduce the cost of order-picking. In working with a partner company, this thesis evaluates a proposed mechanism for piece-picking that would achieve this end. The company has a shelf-pack number for each SKU, whereby the SKU must be piece-picked in a quantity that is a multiple of the number. The company has proposed to change this number from 1 to 2 to raise the number of units per pick and reduce the number of picks needed for a SKU. In this thesis, simulation is performed on the company's shipment data from DC to store to reveal the merits and demerits of this scheme. SKUs are segmented into different groups based on their suitability for this scheme as a means of mitigating the negative repercussions of the proposal. The scheme can reduce the number of picks and related costs needed, but it causes a shift of inventory from DC to store, thus creating an increase in store inventory. However, SKUs can be allotted into groups suitable or unsuitable for the scheme depending on the amount of savings generated for a given amount of impact on store inventory. The scheme's benefits and impact on store inventory are thoroughly examined, and their implications on DC inventory are also discussed. This thesis offers a novel perspective into piece-picking optimization, and it finds the proposed scheme viable, simple, and flexible. / by Stephanie Hsuan-Chia Chen and Eunji Han. / M. Eng. in Logistics