Download or read book Dynamic Scheduling Policies in Production inventory Systems with Returns Or Two Classes of Demands written by Jieling Han and published by . This book was released on 2013 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: A major concern in operations and supply chain management research has been to determine optimal policies to minimize costs in production and inventory systems. This dissertation consists of two applications of production-inventory systems motivated by the real world observations. The first model is motivated by a high-tech company data center server inventory control process. The firm has internalized the production process and faces server returns at the same time. There are demands for both new and used products. Returned servers can be used to serve the demand for use products directly, or be remanufactured into new condition by the same production capacity. Unmet demands are lost. The objective is to determine the optimal scheduling policy that minimizes the discounted total cost. We model the system with a production-inventory model with returns and show the optimal production inventory policy is of base stock type. Efficient heuristics are proposed and the base model is extended to scenarios that better described the real world situation. These scenarios include unmet demand are backordered, bulk demands and returns depending on the demands. The second model analyzes a model of a continuous-time production-inventory system with a shared server serving two demands. Unsatisfied demands are backordered and standard holding and penalty costs apply at each inventory location. The objective is to determine the optimal scheduling policy that minimizes the discounted total cost. The distinguishing feature of our model is that the two demand classes differ in their variability characteristics. The motivation for analyzing such a system is driven by our observations in many real-life contexts where such a difference is reported to exist. Very briefly, practical examples of why the variability of two demand processes, served by the same capacity, may differ include (1) inherent differences in the predictability of the demand, (2) some customers' spiky purchasing pattern influenced by low prices during promotions, (3) mixing emergency and scheduled demands, and (4) the nature of two different markets. Our results allow us to shed some light on implications for managers in such circumstances.

Download or read book Optimal Control and Optimization of Stochastic Supply Chain Systems written by Dong-Ping Song and published by Springer Science & Business Media. This book was released on 2012-11-29 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optimal Control and Optimization of Stochastic Supply Chain Systems examines its subject the context of the presence of a variety of uncertainties. Numerous examples with intuitive illustrations and tables are provided, to demonstrate the structural characteristics of the optimal control policies in various stochastic supply chains and to show how to make use of these characteristics to construct easy-to-operate sub-optimal policies. In Part I, a general introduction to stochastic supply chain systems is provided. Analytical models for various stochastic supply chain systems are formulated and analysed in Part II. In Part III the structural knowledge of the optimal control policies obtained in Part II is utilized to construct easy-to-operate sub-optimal control policies for various stochastic supply chain systems accordingly. Finally, Part IV discusses the optimisation of threshold-type control policies and their robustness. A key feature of the book is its tying together of the complex analytical models produced by the requirements of operational practice, and the simple solutions needed for implementation. The analytical models and theoretical analysis propounded in this monograph will be of benefit to academic researchers and graduate students looking at logistics and supply chain management from standpoints in operations research or industrial, manufacturing, or control engineering. The practical tools and solutions and the qualitative insights into the ideas underlying functional supply chain systems will be of similar use to readers from more industrially-based backgrounds.

Download or read book Research Handbook on Inventory Management written by Jing-Sheng J. Song and published by Edward Elgar Publishing. This book was released on 2023-08-14 with total page 565 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive Handbook provides an overview of state-of-the-art research on quantitative models for inventory management. Despite over half a century’s progress, inventory management remains a challenge, as evidenced by the recent Covid-19 pandemic. With an expanse of world-renowned inventory scholars from major international research universities, this Handbook explores key areas including mathematical modelling, the interplay of inventory decisions and other business decisions and the unique challenges posed to multiple industries.

Download or read book Dynamic Scheduling of Manufacturing Systems with Setups and Random Disruptions written by Fernando Tubilla Kuri and published by . This book was released on 2011 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: Manufacturing systems are often composed of machines that can produce a variety of items but that most undergo time-consuming (and possibly costly) setups when switching between product types. Scheduling these setups efficiently can have important economic effects on the performance of the plant and involves a tradeoff between throughput, inventory, and operating costs. In addition, the schedule must be robust to random disruptions such as failures or raw material shortages, which are common in production environments. In this thesis, we study policies that address the setup scheduling problem dynamically, in response to current conditions in the system. A new heuristic, called the Hedging Zone Policy (HZP), is introduced and developed. It is a dynamic-sequence policy that always produces the current part type at its maximum production rate until a fixed base stock level is reached. Then, before switching setups, the policy might produce the current part type at its demand rate for some additional time. When selecting changeovers, the HZP implements two types of decision rules. If the difference between base stock and surplus level is small for all part types, the item with the largest weighted difference is selected. Otherwise, the policy uses a fixed priority ranking to select between items that are far from their base stock value. In order to demonstrate the benefits of our policy, we also adapt and implement several other heuristics that have been proposed in the literature for related models. The policies are first analyzed in a purely deterministic setting. The stability of the HZP is addressed and it is shown that a poor selection of its parameters leads to a condition in which some low-priority parts are ignored, resulting in an unstable system. Using Lyapunov's direct method, we obtain an easy-to-evaluate and not-too-conservative condition that ensures production of all part types with bounded surplus. We then compare, through a series of extensive numerical experiments with three-part-type systems, the deterministic performance of the policies in both make-to-order and make-to-stock settings. We show that the HZP outperforms other policies within its class in both cases, a fact that is mainly attributed to its priority-based decisions. When compared to the approximate optimal cost of the problem, our policy performs very well in the make-to-order case, while the simplicity of its base stock structure makes it less competitive in the deterministic make-to-stock problem. The results are then leveraged for the study of a stochastic model, where we consider the effect of random disruptions in the form of machine failures. We prove that our model converges to a fluid limit under an appropriate scaling. This fact allows us to employ our deterministic stability conditions to verify the stochastic (rate) stability of the failure-prone system. We also extend our previous numerical experiments by characterizing the performance of the policies in the stochastic setting. The results show that the HZP still outperforms other policies in the same class. Furthermore, we find that except for cases where failures occur much less or much more frequently than changeovers, the HZP outperforms a fixed-sequence policy that is designed to track a pre-determined, near-optimal deterministic schedule.

Download or read book Optimal Dynamic Scheduling Policy for a Make to stock Production System written by Albert Y. Ha and published by . This book was released on 1993 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book New Trends in Distribution Logistics written by M. Grazia Speranza and published by Springer. This book was released on 1999-12-15 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: This text covers the main problems of distribution logistics: network design and location problems, tactical and operational planning of transport, internal logistics, and inventory management. It contains a rigorous methodological approach with an emphasis on practical problems.

Download or read book Production and Inventory Management with Substitutions written by J. Christian Lang and published by Springer Science & Business Media. This book was released on 2009-11-25 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantitativeapproachesforsolvingproductionplanningandinventorymanagement problems in industry have gained growing importance in the past years. Due to the increasinguse of AdvancedPlanningSystems, a widespreadpracticalapplicationof the sophisticated optimization models and algorithms developed by the Production Management and Operations Research community now seem within reach. The possibility that productscan be replaced by certain substitute productsexists in various application areas of production planning and inventory management. Substitutions can be useful for a number of reasons, among others to circ- vent production and supply bottlenecks and disruptions, increase the service level, reduce setup costs and times, and lower inventories and thereby decrease ca- tal lockup. Considering the current trend in industry towards shorter product life cycles and greater product variety, the importance of substitutions appears likely to grow. Closely related to substitutions are ?exible bills-of-materials and recipes in multi-level production systems. However, so far, the aspect of substitutions has not attracted much attention in academic literature. Existing lot-sizing models matching complex requirements of industrial optimization problems (e.g., constrained capacities, sequence-dependent setups, multiple resources) such as the Capacitated Lot-Sizing Problem with Sequence-Dependent Setups (CLSD) and the General Lot-Sizing and Scheduling Problem for Multiple Production Stages (GLSPMS) do not feature in substitution options.

Download or read book Inventory Management with Alternative Delivery Times written by Xiaoying Liang and published by Springer. This book was released on 2016-11-24 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book develops a modeling framework to analyze the problem of inventory management with alternative delivery times. The general context considered here is that a seller replenishes its inventory in fixed intervals and, between replenishments, allocates the limited inventory to satisfy customers who are both price and delivery-time sensitive. On the demand side, customers have heterogeneous delivery-time requirements and choose either spot or late delivery. This theoretical modeling captures the essence of real-world business practices such as the delivery time market segmentation strategy adopted by automobile dealerships in China and many other similar examples. The book focuses on the seller’s optimal inventory replenishment and demand fulfillment policies, and our results provide managerial insights into the merits of flexible delivery-time options. Similar applications such as the group-buying mechanism are also examined. The main mathematical tool used in theoretical analysis is dynamic programming. This book is written for students, researchers, and practitioners in the areas of operations management and industrial engineering who are interested in understanding the rationale of flexible delivery times and designing successful applications.

Download or read book Issues in Industrial Relations and Management 2011 Edition written by and published by ScholarlyEditions. This book was released on 2012-01-09 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Industrial Relations and Management: 2011 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Industrial Relations and Management. The editors have built Issues in Industrial Relations and Management: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Industrial Relations and Management in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Industrial Relations and Management: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.

Download or read book Handbook of Quantitative Supply Chain Analysis written by David Simchi-Levi and published by Taylor & Francis. This book was released on 2004-05-31 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Handbook is a comprehensive research reference that is essential for anyone interested in conducting research in supply chain. Unique features include: -A focus on the intersection of quantitative supply chain analysis and E-Business, -Unlike other edited volumes in the supply chain area, this is a handbook rather than a collection of research papers. Each chapter was written by one or more leading researchers in the area. These authors were invited on the basis of their scholarly expertise and unique insights in a particular sub-area, -As much attention is given to looking back as to looking forward. Most chapters discuss at length future research needs and research directions from both theoretical and practical perspectives, -Most chapters describe in detail the quantitative models used for analysis and the theoretical underpinnings; many examples and case studies are provided to demonstrate how the models and the theoretical insights are relevant to real situations, -Coverage of most state-of-the-art business practices in supply chain management.

Download or read book Performance Analysis of Manufacturing Systems written by Tayfur Altiok and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Manufacturing industries are devoted to producing high-quality products in the most economical and timely manner. Quality, economics, and time not only indicate the customer-satisfaction level, but also measure the manufacturing per formance of a company. Today's manufacturing environments are becoming more and more complex, flexible, and information-intensive. Companies invest into the information technologies such as computers, communication networks, sensors, actuators, and other equipment that give them an abundance of information about their materials and resources. In the face of global competition, a manufacturing company's survival is becoming more dependent on how best this influx of in formation is utilized. Consequently, there evolves a great need for sophisticated tools of performance analysis that use this information to help decision makers in choosing the right course of action. These tools will have the capability of data analysis, modeling, computer simulation, and optimization for use in designing products and processes. International competition also has had its impact on manufacturing education and the government's support of it in the US. We see more courses offered in this area in industrial engineering and manufacturing systems engineering departments, operations research programs, and business schools. In fact, we see an increasing number of manufacturing systems engineering departments and manufacturing research centers in universities not only in the US but also in Europe, Japan, and many developing countries.

Download or read book Using Microsoft Dynamics AX 2012 written by Andreas Luszczak and published by Springer Science & Business Media. This book was released on 2012-04-13 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: Precise descriptions and instructions enable users, students and consultants to easily understand Microsoft Dynamics AX 2012. Microsoft offers Dynamics AX as its premium ERP solution to support large and mid-sized organizations with a complete business management solution which is easy to use. Going through a simple but comprehensive case study – the sample company ‘Anso Technologies Inc.’ – this book provides the required knowledge to handle all basic business processes in Dynamics AX. Exercises are there to train the processes and functionality, also making this book a good choice for self-study.

Download or read book Dynamic Scheduling in Large scale Manufacturing Processing Systems Using Multi agent Reinforcement Learning written by Shuhui Qu and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Scheduling in manufacturing plays an essential role in building smart manufacturing from multiple points of view, including social, economic, and environmental. Optimal scheduling, or the allocation of jobs with different requirements for a manufacturing processing system to meet various objectives, has been discussed for several decades. However, advanced scheduling methods in modern processing systems have not significantly improved, nor have they been widely adopted by staff working on manufacturing production lines despite extensive research conducted into scheduling. Most traditional scheduling methods require statistical assumptions, which cannot support operations for a dynamic and stochastic modern processing system. In addition, most proposed scheduling methods are not sufficiently scalable for managing real-world, large-scale processing systems. To address these limitations, we focus on the dynamic scheduling approach, which involves scheduling real-time events in large-scale modern manufacturing systems, from a data-driven perspective. We implement reinforcement learning (RL) to learn adaptive, scalable, and optimal dynamic scheduling policies, since RL can learn the underlying processing system's patterns and adaptively make allocation decisions based on real-time job and server measurements. The direct application of existing RL methods on the scheduling problem in such large-scale processing systems is impractical and undesired due to the extremely high computational complexity of learning a good scheduling policy. This thesis presents a practical and systematic computational framework that integrates RL with existing expert knowledge at three levels: (1) System-level planning. The planning procedure characterizes the processing system by the nominal feasible region of the scheduling problem. (2) Algorithm-level design. The design of the algorithm in RL is carefully selected as the index-policy-based, multi-agent RL, significantly reducing control policy search complexity. (3) Learning-level demonstration. During the learning process of RL, the existing expert knowledge is used as a demonstration to increase search efficiency and stabilize the RL learning process. We conduct various experiments in both real factory scenarios and simulated environments to evaluate the performance of the framework on processing system scheduling problems. The effectiveness of the proposed index-policy-based, multi-agent reinforcement learning (MARL) method is evidenced by its performance over traditional dynamic scheduling methods, with a linear computational time complexity in regard to the number of machines and job classes.

Download or read book From batch size 1 to serial production Adaptive robots for scalable and flexible production systems written by Mohamad Bdiwi and published by Frontiers Media SA. This book was released on 2023-05-24 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Environmentally Conscious Manufacturing written by and published by . This book was released on 2004 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Digitizing Production Systems written by Numan M. Durakbasa and published by Springer Nature. This book was released on 2021-11-10 with total page 893 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains selected papers from International Symposium for Production Research 2021, held on October 7–9, 2021, online, Turkey. The book reports recent advances in production engineering and operations. It explores topics including production research; production management; operations management; industry 4.0; industrial engineering; mechanical engineering; engineering management; and operational research. Presenting real-life applications, case studies, and mathematical models, this book is of interest to researchers, academics, and practitioners in the field of production and operation engineering. It provides both the results of recent research and practical solutions to real-world problems.

Download or read book Logistics Research Conference written by and published by . This book was released on 1965 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt: