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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.
371

Estimating carbon emissions from less-than-truckload (LTL) shipments

Veloso de Aguiar, Guilherme, Woolard, Mark Anderson 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 86-88). / Less-than-truckload (LTL) is a $32-billion sector of the trucking industry that focuses on moving smaller shipments, typically with weights between 100 and 10,000 pounds, that do not require a full trailer to be moved. Currently, there are no widely accepted methods to estimate carbon emissions from LTL shipments which take into account all the complexities of a typical LTL network. This thesis seeks to address this issue by suggesting a methodology that allows different parties to estimate the emissions of individual LTL shipments with minimal input information. Throughout this research, we worked with C. H. Robinson, a Third-Party Logistics Provider (3PL), and Estes Express Lines, a privately-owned freight transportation company, and analyzed more than 1.5 million shipments. We developed two calculation tools: a detailed model, specifically designed for and based on Estes Express' network and operations, and a lower-precision generic model, adapted from the detailed one so that it could be applied to carriers whose network characteristics are unknown. We also assessed current estimation methods and found that they tend to underestimate the emissions from LTL shipments primarily because (1) they rely on direct over-the-road distances as opposed to actual shipped distances, which must include the intermediate stops, and (2) they fail to factor in the pick-up and delivery (P&D) sections, focusing solely on line haul operations. Therefore, while existing initiatives such as the GHG Protocol and the EPA SmartWay program provide guidance on how to estimate carbon emissions from transportation in general, the LTL industry still needs a specific approach that takes into account all of its unique characteristics. This thesis provides a contribution in that direction by suggesting a methodology to better estimate the carbon emissions of individual LTL shipments. / by Guilherme Veloso de Aguiar and Mark Anderson Woolard. / M. Eng. in Logistics
372

The medication mismanagement system : causes, evidence of user innovation, and a view towards a product/service solution for the elderly

Hanson, Joshua A. (Joshua Alan) January 2010 (has links)
Thesis (S.M. in Management and Engineering)--Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2010. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 77-78). / Introduction: What could be easier than taking a pill? The doctor prescribes it, the pharmacist provides it and the patient swallows it with a glass of water twice a day for a cure; a very straightforward system of cause and effect. Unfortunately, statistics show that 66% of all Americans fail to take any of their prescription medicines (American Heart Association, 2009) and as a result many of the medical innovations that have increased life expectancy by 47 years since 1900 (Wan He, 2005) remain left unclaimed. So why than do Seniors, facing the pain of arthritis or the impending certainty of death from congestive heart failure, refuse to take their pills? The first half of this thesis seeks an answer to this question while debunking the view that this is a simple problem of ignorance or laziness on the part of the patient. In place of this oversimplified view, the problem of "medication management" is defined and cast in an in-depth and nuanced way that includes issues involving the patient, their caregiver, the disease state, social circumstances and financial constraints. The second half of this thesis focuses on possible solutions. While rethinking the entire medication system can result in great gains, the innovations discussed (both lead user and off-the-shelf innovations) all work within the current medication system and are addressable by product/service designers. By adhering to these two constraints the resulting solutions remain quickly implementable, cost effective and relevant to industry. In the end we find that end users have created a series of innovations and product modifications that address the physical and cognitive barriers they face, while product manufactures are innovating products and services that address the motivational issues users face. / by Joshua A. Hanson. / S.M.in Management and Engineering
373

System development technical interactions and innovation : a network-based investigation

Makumbe, Pedzisayi O January 2006 (has links)
Thesis (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division, 2006. / Includes bibliographical references (leaves 70-77). / The development of complex engineering systems such as aircraft engines involves many cross functional teams that are usually geographically distributed. These teams interact in several ways but one of the most important set of interactions during the product development phase is the flow of technical information which is largely used for coordination and problem solving. For analytical purposes, these technical information flows can be represented as a directed network. This thesis develops a context and a research design that can help one investigate the impact of the resultant network structure on innovation in complex engineering systems. The broad context can be divided into two: theoretical and real world contexts. The theoretical context is developed by reviewing literature at the intersection of networks and innovation, and the real world context is typified by a modular enterprise developing a complex engineering system. Within this broad context, the research area of interest is framed by a set of hypotheses that lead to precise innovation measures and characterizations. The research design is motivated by the context and intended theoretical contributions. It consists of two major sections. / (cont.) The first section discusses and critiques methodologies for constructing networks and proposes a methodology more suited to this engineering systems development context. The second section describes a two-stage model whose variables include network structural properties such as structural holes, nodal degree, tie strength, and innovation output. It also describes a methodology for investigating the relationship between network density and the innovation development subprocess. Finally, the context and research design are tied together to create an instantiation of the measurement and characterization of innovation in complex engineering systems development. The characterization considers product innovation as radical, architectural, modular or incremental, and process innovation as organizational / coordination-based or technical. The measures of innovation include granted patents, implemented employee suggestions, product literature based innovation counts and results from structured interviews with the two leaders from each node in the network. / by Pedzisayi O. Makumbe. / S.M.
374

Qualitative knowledge construction for engineering systems : extending the design structure matrix methodology in scope and procedure

Bartolomei, Jason E January 2007 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, 2007. / MIT Barker Engineering Library copy: printed in pages. / Also issued printed in pages. / Includes bibliographical references (leaves 141-146). / This thesis presents a new modeling framework and research methodology for the study of engineering systems. The thesis begins with a formal conceptualization of Engineering Systems based upon a synthesis of various literatures. Using this conceptualization, a new modeling framework is presented called the Engineering Systems Matrix (ESM). The ESM is an improvement to existing system-level modeling frameworks, such as the Design Structure Matrix (DSM), by providing a dynamic, end-to-end representation of an engineering system. In support of this contribution, a new research methodology is presented called Qualitative Knowledge Construction (QKC). QKC can be thought of as a Bayesian-type approach to grounded theory. The methodology integrates qualitative social science with quantitative methods by developing a procedure for translating textual reports of observations, interview transcripts, system documentation, and figures into coded data represented in the ESM. The thesis develops the ESM framework and the QKC methodology in the context of a real world engineering system, a US Air Force miniature uninhabited air vehicle (MAV) product development system. / by Jason E. Bartolomei. / Ph.D.
375

The role of CCS as a mitigation technology and challenges to its commercialization / Top-down & bottom-up approach to analyzing the role of CCS as a mitigation technology and challenges to its commercialization / Role of carbon capture and storage as a mitigation technology and challenges to its commercialization

Raveendran, Sadia P January 2013 (has links)
Thesis (S.M. in Technology & Policy)--Massachusetts Institute of Technology, Engineering Systems Division, 2013. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 103-112). / Greenhouse gases are being emitted at an increasing rate, which may cause irreversible damage to the earth's climate. Considering the magnitude of CO₂ emissions from industrial facilities and power plants, carbon capture and storage (CCS) is expected to play an important role in mitigating climate change. The estimated contribution of CCS to a given emissions reduction target depends on assumptions made about various factors such as the availability of the technology, the availability of substitutes such as nuclear technology, and the stringency of emissions reduction targets. Given that the global energy economy has largely been operating in "business as usual" mode, the effective implementation of a carbon policy is likely to be delayed. In addition, other trends in the energy sector such as the availability of inexpensive gas-based generation and the uncertainty related to nuclear capacity expansion may also have an impact on the role of CCS. Part A of this thesis analyzes the importance of CCS as a mitigation technology under different future policy responses and incorporating these current trends. Using the Emissions Prediction & Policy Analysis (EPPA) model developed by the Joint Program on the Science & Policy of Global Change at the Massachusetts Institute of Technology (MIT), the study finds that the more stringent the emission caps, the more important the role of CCS becomes. In addition, the role of natural gas based generation is found to be transitional in its contribution to emissions reduction. Consequently, the availability of inexpensive gas-based generation does not eliminate the need for CCS towards the end of the century. Furthermore, advanced nuclear technology and CCS are found to be close substitutes for technologies that serve the needs of a low-carbon economy in the latter half of the century. The role of one technology, therefore, is in part determined by how technological development and cost reduction occurs in the other. Part B of this thesis focuses on challenges experienced in the current demonstration phase of CCS technology development. Most demonstration projects are typically supported by a combination of policy incentives such as grants, investment tax credits, production tax credits, loan guarantees, or additional sources of revenue. Regardless, many of these demonstration projects have been cancelled in the recent past primarily due to poor project economics. A financial model was developed and used to analyze the impact of each of these policy incentives on project economics. In addition, case studies have been conducted on two major demonstration projects: ZeroGen (Australia) and the Kemper Country (USA). The study finds that even with the combined impact of all incentives, first-of-a-kind CCS plants are not economical when compared to supercritical pulverized coal plants. CCS and similar low carbon technologies are also facing increasing economic pressure from cheaper natural gas-based electricity. These factors, in addition to endogenous risks associated with first-of-a-kind plants, are likely to deter potential developers. Therefore, CCS demonstration plants may require other policy mechanisms such as a rate-based pay that allow costs to be passed on to consumers. Policymakers may need to consider the distributional impacts of such a mechanism because costs are borne by consumers within a particular jurisdiction whereas the benefits of commercializing CCS accrue to a larger group of consumers. Regardless, incurring costs in the short-term may be inevitable to ensure the availability of CCS as a competitive, longer-term low carbon technology option. / by Sadia P. Raveendran. / S.M.in Technology & Policy
376

An analysis of reverse logistics technology and service for hi-tech industry

Li, Jinfan, 1976- January 2004 (has links)
Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2004. / "June 2004." / Includes bibliographical references (leaf 52). / This thesis provides a method for hi-tech companies to evaluate reverse logistic software and services. To clarify what is reverse logistics, the definition and features of reverse logistics are first introduced. The reasons to improve reverse logistics management systems are explained. Information of reverse logistics software systems and service vendors is collected, compared and analyzed. Current reverse logistics market trends are analyzed and problems in evaluating reverse logistics systems are identified. An algorithm to evaluate the software and service is established and explained. Parameters are analyzed and determined. Various vendors are selected and interviewed. Their capabilities/strengths are rated. As an example, the evaluation points for several software systems are calculated in the case of a semi-conductor company. Research limits are also provided. Conclusions are presented at the end of the thesis. / by Jinfan Li. / M.Eng.in Logistics
377

Assembling the crystal ball : using demand signal repository to forecast demand / Using demand signal repository to forecast demand

Rashad, Ahmed (Ahmed Fathy Mustafa Rashad Abdelaal), Spraggon, Santiago January 2013 (has links)
Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2013. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 60). / Improving forecast accuracy has positive effects on supply chain performance. Forecast accuracy can reduce inventory levels, increase customer service levels and responsiveness, or a combination of the two. However, the further upstream in the supply chain, the more difficult it becomes to forecast accurately. Demand for consumer products might be subject to factors that are hard to identify and quantify. One way to overcome this is to observe external factors or predictors that might help explain demand. The purpose of this thesis is to explore the factors that potentially influence the demand of a fast-moving consumer product (bottled water), and build a demand signal repository for these factors to help the manufacturer generate more accurate forecasts. We identified more than 30 such factors that might affect demand, using interviews and industry research. We tested more than 200 causal models of the relationship between observed demand and the predicting factors. The resulting model explained almost 60% of demand for two out of three customers using daily buckets and over 85% using weekly buckets compared to less than 50% using time-series techniques. Using the results of this extensive analysis, we propose a new forecasting model. We also identified additional factors that could not be included this analysis due to the lack of data; adding these to the model may further improve the forecast accuracy. / by Ahmed Rashad and Santiago Spraggon. / M.Eng.in Logistics
378

Biofuels supply chain characterization

Banerjee, Anindya, M. Eng. Massachusetts Institute of Technology, Noguer, José Luis January 2007 (has links)
Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2007. / Includes bibliographical references (leaves 84-89). / Ethanol can be made from agricultural residues like wheat straw and from crops dedicated to energy use, like switchgrass. We study the logistics aspects of this transformation and determine the main characteristics of the supply chain making ethanol from cellulose. Important to the final acceptability of ethanol as a transportation fuel is both the economics as well as the environmental aspect of using ethanol. In this study we analyze the buildup of cost as biomass is transformed into fuel. We also look at all the steps involved and describe them from a supply chain perspective We have found that the main cost components in the cellulosic ethanol production are biomass production, harvesting and ethanol refining. We have also found that the main factor in reducing the overall production cost is the biomass to ethanol conversion factor. The development of new technologies to convert biomass into ethanol becomes a critical issue to achieve the cost targets imposed in order to make ethanol more competitive with other sources of energy such as fossil fuels. An increase in the current conversion factor of 42% could potentially yield to a decrease of nearly 15% in the: total production cost of cellulosic ethanol. / (cont.) Other factors such as increasing the refining plant size and biomass yield can also help to reduce the production cost but we found its impact to be lower than that of the conversion factor. Finally, we also performed a strategic analysis of the entire supply chain to determine how is this industry likely to develop and who will have more bargaining power and therefore will realize most of the value and profits in the supply chain. Our analysis shows that in such a dynamic scenario as in the alternate energy industry, the best option is to build sustained advantage by strong alliances with different partners within the supply chain. / by Anindya Banerjee [and] José Luis Noguer. / M.Eng.in Logistics
379

Adapting the Lean Enterprise Self Assessment Tool for health care / Adapting the LESAT for health care

Hernandez, Cynthia Lynn January 2010 (has links)
Thesis (S.M. in Engineering and Management)--Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2010. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 61-63). / The Lean Enterprise Self Assessment Tool (LESAT) is a product of the Lean Advancement Initiative (LAI) and the Massachusetts Institute of Technology. This tool has been applied by many organizations to gage their progress toward lean enterprise management, however applying this tool in health care organizations has been inhibited by language and underlying assumptions from product manufacturing. An adaptation of the LESAT specifically for health care is proposed. Review of the literature and special reports on health care are used in determining the recommended changes. "Product life cycle" is reinterpreted as a health care service cycle and context specific enterprise level processes and practices are presented. Comparison to other industry measures shows the content the LESAT for health care to cover all key issues and practices for high quality health care delivery. / by Cynthia Lynn Hernandez. / S.M.in Engineering and Management
380

Impact of product complexity on inventory levels

See, Ying-Lai, Namkoong, Jin January 2006 (has links)
Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2006. / Includes bibliographical references (leaves 62-63). / In this thesis we consider a manufacturing and distribution supply chain of a roll-based product whose width comes in 1-cm increments. We formulate a computer model subject to stochastic, inelastic demand to determine the relationship between width interval and finished goods inventory levels. Assuming that the supply chain operates with the same set of policies regardless of the width interval value, we illustrate that the value of risk pooling diminishes as the interval widens. Due to the presence of a counteracting effect, we also demonstrate that increasing the width interval does not always reduce the amount of inventory requirements. Lastly, we show that the supply chain can operate with lower inventory levels without compromising the service level by pushing the inventory down the chain. / by Ying-Lai (Chandler) See [and] Jin Namkoong. / M.Eng.in Logistics

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