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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
431

A multi-echelon supply chain model for strategic inventory assessment through the deployment of kanbans

Hodge, Philip J. (Philip James), Lemaitre, Joshua D January 2008 (has links)
Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2008. / Includes bibliographical references (leaves 100-102). / As global competition in the manufacturing space grows, so do corporations' needs for sophisticated and optimized management systems to enable continuous flows of information and materials across the many tiers within their supply chains. With the complexities introduced by the variability in the demand for finished goods as well as by the variability in lead-time of transportation, procurement, production and administrative activities, corporations have turned to quantitative modeling of their supply chains to address these issues. Based on the data of a heavy machinery manufacturer headquartered in the US, this research introduces a robust model for the deployment of strategic inventory buffers across a multi-echelon manufacturing system. Specifically, this study establishes a replenishment policy for inventory using a multiple bin, or Kanban, system for each part number in the assembly of products from our sponsors tractor line. We employ a numerical simulation to evaluate and optimize the various inventory deployment scenarios. Utilizing several thousand runs of the simulation, we derive a generalized treatment for each part number based on an econometric function of the parameters associated with lead-time, order frequency, inventory value and order costing. The pilot for the simulation focuses on the parts data for three earthmoving products across eight echelons, but scales to n products across m echelons. Our results show that this approach predicted the optimal quantities of Kanbans for 95% of parts to a level of accuracy +/- 3 bins. / by Philip J. Hodge and Joshua D. Lemaitre. / M.Eng.in Logistics
432

21st century reverse logistics : consumer to business space explored / Twenty-first century reverse logistics

Fleck, Jonathan M. (Jonathan Michael), 1974- January 2000 (has links)
Thesis (M.Eng.)--Massachusetts Institute of Technology, Engineering Systems Division, 2000. / Includes bibliographical references (leaves 58-64). / Despite a growing body of information about the importance of good logistics and supply chain management, there remains a dearth of research regarding consumer-to-business reverse logistics (the collection of processes required to move individual goods from individual end-consumers to the appropriate retailer, manufacturer, or third party). Indeed, there is not a comprehensive framework to assist enterprises in understanding, evaluating, creating, implementing, or changing a consumer-to-business reverse logistics policy of program. Given the growth of e-commerce and the Internet channel, where goods are often delivered to end-consumers in quantities of one and may likely be returned in quantities of one, this absence of a framework is peculiar. This thesis seeks to fill that gap by utilizing analysis of existing literature, as well as extrapolation of recent trends and developments in reverse logistics service offerings, technology, and last mile solutions. The results are that there is enough available information on the processes and issues surrounding consumer-to-business reverse logistics that a flexible and pragmatic framework can be proposed for use in the United States. This is accomplished by synthesizing results with original analysis, thought, and context. Though the framework cannot be considered comprehensive, it does provide an initial tool for critique and improvement. / by Jonathan M. Fleck. / M.Eng.
433

Application of Supply Chain Risk Management through visualization and value-at-risk quantification

Xia, Diwei, Lu, Kaiye January 2014 (has links)
Thesis: M. Eng. in Logistics, Massachusetts Institute of Technology, Engineering Systems Division, 2014. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 46-47). / Supply Chain Risk Management ("SCRM") is often discussed in business and academia but is still underdeveloped as a practical tool. Many studies have examined the effects of supply chain disruptions, and many studies have also produced tools for mitigating risk. However, there is still a need for an integrated, practical approach for SCRM that businesses can implement on an enterprise scale. Our thesis attempts to bridge this gap and produce a practical approach for corporations to deploy a SCRM strategy on an enterprise level. Through the use of supply chain visualization and catastrophe modeling software, we have developed a SCRM strategy for a large multi-national chemical company. Our SCRM framework focuses on four key steps: 1) defining the scope of supply chain disruptions; 2) mapping and visualizing the supply chain; 3) evaluating the probability of disruption; and 4) developing a strategy to create an economically resilient supply chain. / by Diwei Xia and Kaiye Lu. / M. Eng. in Logistics
434

Mitigating security issues in the evolving DNA synthesis industry

Turlington, Ralph Donald, III January 2013 (has links)
Thesis (S.M. in Technology and Policy)--Massachusetts Institute of Technology, Engineering Systems Division, 2013. / This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. / Cataloged from student-submitted PDF version of thesis. / Includes bibliographical references (p. 102-108). / DNA synthesis technologies are advancing at exponential rates, with production of ever longer, more complex, and less expensive sequences of double stranded DNA. This has fostered development of industrial scale design, construction, and sale of synthetic DNA. The tools and methods of synthesis used to create beneficial genetic material can also be used to construct dangerous pathogens. To prevent unknown actors from ordering potentially dangerous genetic material, the largest DNA synthesis firms formed two industry associations that require members to screen the DNA sequences ordered and the customers ordering sequences. The firms also worked with the U.S. Health and Human Services to formulate voluntary screening guidelines for synthetic double stranded DNA. As DNA synthesis technology advances and diffuses, this centralized voluntary approach may become less effective. This thesis identifies strengths and weakness in the current voluntary regime and offers recommendations to improve security in the DNA synthesis industry. It describes the origins and current status of DNA synthesis technologies and the structure of the DNA synthesis industry. Then, it describes the formation of voluntary screening consortia and the U.S. and international guidelines that address security issues in DNA synthesis. Finally, this thesis compares DNA synthesis with other potentially "dual use" technologies, concludes that regulatory approaches may not enhance security in this area, and suggests that governments should focus on education and outreach. / by Ralph Donald Turlington III. / S.M.in Technology and Policy
435

Case study of the competitive behavior of companies in response to disruptive technologies in the dynamic environment of changing user needs

Naumov, Sergey A January 2013 (has links)
Thesis (S.M. in Engineering and Management)--Massachusetts Institute of Technology, Engineering Systems Division, 2013. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 123-128). / Innovations are part of everyday reality in the business life of many companies. While for startups, success in business largely depends on success of innovations as they are trying to enter the market, for large monopolistic companies the influx of innovations is a crucial part of strategic decision-making. In a fast clockspeed high technology market, innovations are being introduced every day and have to be evaluated to identify potential threat to existing technology and market share of an incumbent. It is extremely difficult to understand if this new technology is something relevant to the market and will be adopted fast by customers, or it is merely one of many attempts, that will prove unsuccessful. Overarching questions for this work is "Why does the same technology become dominant in some cases while failing in others?" This work focuses on considering several real life examples with different outcomes through the lens of the Incumbent's Dilemma framework. The goal is to identify patterns of dynamics for several typical innovation scenarios and provide explanations that might be useful for product managers as well as top management of any company who want to understand how to use innovations to improve business performance and gain market share. / by Sergey A. Naumov. / S.M.in Engineering and Management
436

Application of real options to reverse logistics process

Kaga, Akihiro, 1975- January 2004 (has links)
Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2004. / "June 2004." / Includes bibliographical references (leaves 104-106). / In this thesis, real options are used to identify the optimal model for the reverse logistics process of a technology company in the circuit board business. Currently, customers return defective boards and the company repairs the boards and sends them back. Now that the new product cost is falling below the level of the repair cost, the company is considering an alternative operational model, which is to scrap the returned boards and swap them with new products. As the product cost declines, it is also widely fluctuating, and it is this fluctuation that makes the switching option between the repair and swap model valuable. The repair and swap models (with and without switching options) will each produce different cost saving amounts with different degrees of risk. As a result of real options analysis, the swap model with the switching option to repair is determined to be optimal and has only modest risk. Specifically, the costs would be reduced by $1.3 million (of which $0.9 million is the option value) and by 18% compared to the costs under the current model, and the volatility will only moderately increase from 8% to 11%. However, it should be noted that the model is sensitive to both volatility and switching cost. Unlike the traditional methodologies, such as optimization or discounted cash flow analysis, real options quantifies the option value as well as the risk and hence shows the maximum investment necessary to obtain the option. That being said, in this thesis, optimization (the news vendor approach), simulation (Monte Carlo simulation), and discounted cash flow analysis take complementary roles to real options analysis. The option value is significant when the key uncertainties (e.g., the product cost, repair cost, and volume) are volatile / (cont.) because the option allows businesses to capture upside opportunities while protecting them from downside risks. / by Akihiro Kaga. / M.Eng.in Logistics
437

The value of electricity storage under large-scale penetration of renewable energy : a hybrid modeling approach

Octaviano Villasana, Claudia Alejandra January 2015 (has links)
Thesis: Ph. D., Massachusetts Institute of Technology, Engineering Systems Division, 2015. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 219-234). / Due to the physics of electricity, and the current high costs of storage technologies, electricity generation and demand need to be instantaneously balanced at all times. The large-scale deployment of intermittent renewables requires increased operational flexibility to accommodate fluctuating and unpredictable power supply while maintaining this balance. This dissertation investigates the value of electricity storage for the economy. Specifically, what is the value of storage under large-scale penetration of renewable energy in the context of climate policy? To answer this question, I develop a new hybrid modeling approach that couples an electricity sector model to the MIT EPPA model, a general equilibrium model for climate change policy analysis. The electricity sector model includes the main constraints for reliable and secure operation; electricity demand; wind, solar and hydro resources on the hourly time-scale; and utility-scale storage technologies. The hybrid modeling approach reconciles the very short-term dynamics required for renewables and storage technologies assessment, and the long-term time-scale required for the analysis of economic and environmental outcomes under climate policy. Using Mexico as a case study, this dissertation analyses policies currently under discussion in the country. The experimental design explores increasing shares of renewables with varying levels of storage capacity. Under scenarios with increasing shares of renewables in the power grid, the value of storage increases sharply. By 2050, with 50% renewables penetration, the present value of storage capacity per MW installed in Mexico is estimated at $1500/MW and $200/MWh. Energy management services resulted in the highest value component (58%), followed by operational reserves provision (22%) and capacity payments (18%). Storage capacity in the system changes both investments and operational decisions, allowing larger penetration of wind technologies and displacing gas technologies. Storage capacity in the system reduces price volatility and the occurrence of negative prices that would otherwise result as renewables scale up. The general equilibrium analysis shows that the availability of competitive storage technologies under an economy-wide climate policy reduces the overall policy costs. Simulating a 50% emissions reduction by 2050, the model demonstrated that storage could decrease total welfare losses by 0.7% when compared to the case without storage. Despite the sharp increase in the value of storage driven by renewables penetration, the findings suggest that the current cost of most storage technologies will still have to drastically be reduced for them to be economical. / by Claudia Alejandra Octaviano Villasana. / Ph. D.
438

Modeling mining economics and materials markets to inform criticality assessment and mitigation

Poulizac, Claire Marie Franc̦oise January 2013 (has links)
Thesis (S.M. in Technology and Policy)--Massachusetts Institute of Technology, Engineering Systems Division, 2013. / This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. / Cataloged from student-submitted PDF version of thesis. / Includes bibliographical references (p. 139-143). / Conventional criticality-assessment methods drawn from the existing literature are often limited to evaluations of scarcity risks, or rely on price as an indicator of criticality. Such approaches, however, are ill-suited to a firm's material procurement planning. A simulation tool - the m:5 model - has been developed to model the behavior and dynamics of materials markets. Grounded on economic theory, the model also draws upon the characteristics of mining economics and market imperfections, while offering a flexible structure adaptable to different markets and requiring few inputs. The m:5 model has been designed to enable manufacturers and policy-makers to compare the outcomes of different scenarios, informing decisions about material purchasing and market regulation. Model results illustrate common behaviors of materials markets viewed as critical, such as those of Rare Earth Elements and Platinum Group Metals. Analyses illustrate the interaction between demand growth rate and market concentration, as well as the impact of price elasticity of demand on market behaviors. Moreover, an effective recycling stream is shown to be an efficient policy to mitigate price excursions, especially in the presence of disruptive events. A variety of potential private and public mitigating policies are assessed in light of model results, to address common risks encountered in critical materials markets. In addition, this thesis presents how the model can be used to actually develop and compare such policies. While the initial purposes of the model - namely, enabling scenario comparisons and gaining qualitative insights on specific materials markets - has been fulfilled in this work, future developments on the model could include the endogenous treatment of recycling and adding price-responsiveness to the handling of stock, so as to refine its correspondence to actual markets' behaviors. / by Claire Marie Franc̦oise Poulizac. / S.M.in Technology and Policy
439

Third party logistics : an analysis of the feasibility and contexts of strategic relationships

Ranjan, Madhu, 1972-, Tonui, Richard, 1975- January 2004 (has links)
Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2004. / "June 2004." / Includes bibliographical references (leaves 67-68). / An important topic in the Third Party Logistics (3PL) industry is the extent to which customers view 3PL services as pure-commodities to be re-bid. The trend towards commoditization has been one of the causes for current pricing pressures on the 3PLs. The 3PLs gearing towards "strategic partnerships" and the addition of Value-Added Services to their portfolio could decelerate the trend towards commoditization and could also otherwise differentiate them from their competitors. This study investigates the categories of relationships that 3PLs have and specifically the presence of strategic relationships in the 3PL industry. The study also examines the contexts in which they exist and highlights the factors that have contributed to the formation of the strategic relationships. The study concludes by proposing steps that 3PLs can take to better position themselves as candidates for strategic relationships. / by Madhu Ranjan [and] Richard Tonui. / M.Eng.in Logistics
440

Transportation resource scheduling in food retail industry / Transportation resource scheduling in grocery industry

Akkas, Arzum, 1978- January 2004 (has links)
Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2004. / Includes bibliographical references (leaves 87-88). / The objective of this thesis is to find an appropriate analytical method for scheduling the daily driver tasks in the grocery industry. The goal is to maximize driver utilization. A "Bin-packing" approach is employed to solve the problem. A Bin-packing problem concerns packing a list of items into the minimal number of unit capacity bins. In our problem, the drivers correspond to the bins and the daily delivery tasks are equivalent to the items, where we use time units to measure bin capacity. The model is applied to characterize the operation of a grocery company. Several bin-packing algorithms are implemented on two weeks of delivery data, which represent the company's transportation demand. The driver requirements are calculated and compared with their actual assets. Driver requirements are assessed on a per-day basis, considering the volatility in transportation demand over the course of the week. The performance of a given bin-packing algorithm is measured by how well it maximizes driver utilization and balances the workload among the drivers. The model's solution generated labor savings and proved that better resource allocation is possible by considering the demands of the various dispatching locations and the days of the week. Extension of the current model to capture the time window constraints of the delivery locations is proposed for future further research. / by Arzum Akkas. / M.Eng.in Logistics

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