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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.
221

Multi-criteria design analysis of sensor systems for railway level crossings

Miyashita, Yu, S.M. Massachusetts Institute of Technology. January 2020 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, September, 2020 / Cataloged from the official version of thesis. / Includes bibliographical references (pages 100-102). / The prevention of railway accidents on level crossings is of critical importance for railway companies because of their high frequency and considerable severity. As a countermeasure against the accidents, obstacle detection systems are widely installed and used in a large number of level crossings in Japan. However, current obstacle detection systems can typically detect only automobiles and not pedestrians and can be improved in accuracy and reliability performance. This thesis develops a method for effectively determining the best combinations of sensors that can detect human-sized objects on railway level crossings with the highest utility and least costs. The method assesses combinations of up to three sensor technologies such as LIDAR, stereo camera, and millimeter laser radar. We evaluate each sensor and find the best combination of multiple sensors according to a set of performance criteria. The analysis was conducted using empirical data of 1,800 high-risk level crossings in Japan. The results show that if uniform emphasis is given to criteria related to safety and stability as well as when emphasis is solely on safety or solely on stability, in all cases the highest utility at lowest cost is provided by wide lens stereo cameras. The utility increases by 36% if a combination of stereo cameras and LIDARs are used, however the cost of such two-sensor systems increases by four folds. A system safety analysis was also performed, and transportation safety from the viewpoint of not only sensors but also the larger system that includes humans was analyzed. Using the Systems Theoretic Process Analysis, we find that the system safety is highly dependent on both human factors and system structure. The analysis results show that automating the emergency braking system can be an effective countermeasure against railway accidents caused by humans. Overall, the analysis tool developed in this work allows for analysis and simulations to be easily updated with new performance specifications of sensors and utility functions. The tool can be used for rapidly analyzing new systems when new types of sensors become available, costs change, or new sets of criteria for system performance (expressed as a utility) need to be assessed. / by Yu Miyashita. / S.M. in Engineering and Management / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program
222

Improved reservoir characterization by incorporating geodetic data in a western Kazakhstan oilfield

Pickering, Michael Vance. January 2020 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, September, 2020 / Cataloged from the official version of thesis. / Includes bibliographical references (pages 135-139). / Reservoir characterization for petroleum systems stands as a key source of competitive advantage amongst operators. Exploration and field development activities require large investments of engineering time and capital to be made in pursuit of improved short- and long-term economic decision-making posture. For this reason, identifying workflows from adjacent earth science fields of study to tackle reservoir characterization challenges is of utmost importance. Examined in this thesis is the idea of whether improved reservoir characterization can be a corollary of the modern advancements in geodesy. This thesis proposes a holistic workflow to improve subsurface reservoir characterization using commercially available tools and insights by incorporating modern Interferometric Synthetic Aperture Radar (InSAR) geodetic data to better inform model assumptions. Surface deformation measurement by InSAR is used to provide subsurface insights using as an example the "Polygon" field in Kazakhstan. This workflow leads to several key conclusions which could only be realized traditionally by drilling additional exploratory wells to collect the necessary data. Firstly, early seismic field work identified the presence of several faults which divide the area of study into three distinct blocks, which were assumed to be impermeable at the boundaries. However, due to the flow directions and rock deformation observed in the simulated reservoir and geomechanical models, only one of the three blocks exhibits "compartmentalization," or impermeable bounding at the faults. With a displacement of 20 meters at the fault faces, expected permeability values for these fault boundaries were anticipated to be less than 1 millidarcy of permeability; however, permeability above 1 Darcy exists across two of the three block fault boundaries. The geomechanical model of the reservoir predicts subsidence at surface while InSAR shows localized uplifts of several centimeters on the western and eastern edges of the studied blocks. The only way to match the subsurface geomechanics model with the directly measured InSAR is to implement a no-flow boundary at the eastern fault that delineates the westernmost block. As a result, a strategy for improved recovery efficiency from the western compartmentalized block is proposed to enhance pressure maintenance and improve waterflood effectiveness. Also, further geomechanical and InSAR comparison suggests the presence of a weak edge aquifer influx behavior in the area of study flowing north to south. In summary, the combination of reservoir simulation, geomechanical modelling, and direct InSAR measurement represents a significant opportunity for improving reservoir characterization using readily available techniques at an incrementally low cost. / by Michael Vance Pickering. / S.M. in Engineering and Management / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program
223

Data driven artificial intelligence techniques in renewable energy system

Ning, Ke. January 2021 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, February, 2021 / Cataloged from the official version of thesis. / Includes bibliographical references (pages 60-66). / Today's power grid is composed of different kinds of distributed energy resources (DER) such as solar panels, wind farms, batteries and power transformers. DERs often come with data interfaces and IoT sensors which generate large amounts of data. Besides monitoring device status, those data can be utilized to improve system efficiency and generate additional values. My thesis is to examine the benefits of technologies that incorporate AI algorithms on the growing DER data in a technical perspective; First, a new field after IoT technology, called AIoT (Artificial Intelligence Internet of Things) is introduced, which are new technologies combining artificial intelligence (AI) and IoT to each other and creating new opportunities in the distributed energy resources (DER) field. Second, the thesis focuses on three areas of AIoT applications (1) fault prediction in photovoltaic system and power transformers; (2) remaining useful life (RUL) prediction of IoT enabled equipment; (3) AI-enabled algorithms can automate processes and make real time grid system optimization, such as energy storage, demand response (DR) and grid flexibility. The main focus is on data driven AI techniques that differentiate from traditional statistics or knowledge-based systems, present algorithm applicability, compare improvement over traditional method and business value created in each area. Finally, in the smart grid concept, all AIoT powered distributed energy resources (DER) can be aggregated in terms of virtual power plant (VPP), which enable the management of efficient and reliable power network on a large scale, and coordinate demand and supply in real-time. The AI enabled VPP architecture is presented, which utilized all the AIoT technologies and can provide valuable system capacity, flexibility and reliability. / by Ke Ning. / S.M. in Engineering and Management / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program
224

Deal rationales for technology M&A : an analysis of the two year value generated / Deal rationales for technology mergers and acquisitions

Manyala, Sucharitha. January 2021 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, February, 2021 / Cataloged from the official version of thesis. / Includes bibliographical references. / The technology sector is driven by rapid innovations, the pace and magnitude of technological changes and complexities, and a reliance on specialized skills and expertise. Not all firms are able to organically develop all the technologies and capabilities they need to stay competitive. Mergers and acquisitions (M&A) give buyers looking to achieve strategic goals an alternative to organic growth. Technology companies have often pursued M&A as a means to acquire new technology, as an alternative to organic technology development. Strategic motives such as broadening scope, achieving cost synergies, getting access to skills or technologies faster, and several others drive companies to engage in M&A. These motives are widely reported in the literature and are deemed to be critical in improving an organization's financial performance and increasing shareholder value. This thesis summarizes a subset of these motives or deal rationales that are most prominent in the technology sector, analyzes a sample of past technology deals between 2008 and 2018, and categorizes them based on the strategic intent behind the deal-making. This study examines the long-term value these motives generate in each category by measuring and comparing financial metrics pre- and post-merger. Various financial metrics like quick-ratio, CAGR (compound annual growth rate) and total shareholder return (TSR) are analyzed in the process and ultimately TSR has been chosen to measure the long-term value of the deals in this study. This study concludes "Cross-Selling" and "Acquiring technical capabilities" as having probability of higher returns and higher success rate among those studied. / by Sucharitha Manyala. / S.M. in Engineering and Management / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program
225

The potential for plant-based Meat in Africa - a proposed new approach using a system design methodology

Smith, Thomas Llewellin. January 2021 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, February, 2021 / Cataloged from the official version of thesis. / Includes bibliographical references (pages 55-58). / This Thesis explores the potential application of new plant-based protein technologies to Sub-Saharan Africa. It demonstrates the use of a system design methodology to evaluate, assess and select a new approach to protein production. This is an important topic, because global protein production systems are under pressure to reduce their environmental footprint. It is an interesting topic right now, because new protein technologies are emerging which have the potential to soon disrupt industrial livestock farming. The system design approach means thinking in terms of protein production as a system consisting of individual parts (farms, value chain, retail outlets etc.) and their interactions, which together deliver value to the protein consumers. The stakeholders and users of the system are analyzed in order to understand and prioritize their needs in terms of the system goals. This approach allows us to creatively examine the individual parts for alternatives, whilst assessing expected system performance in terms of the overall value delivered over time. The Thesis focuses on Africa's fast-growing and fast-urbanizing populations with their growing demand for protein. A common operating factor is malnourished populations, due to diets based on low-quality plant sources, and existing protein production systems which are inefficient, unsustainable and harming the environment. The work thoroughly analyses published research on the technical and operational aspects of new and old protein production. Interviews were conducted with experts in both protein and Africa. The comparison of new techniques for producing proteins suggest that new plant-based methods have the most immediate potential. The proposed system is based upon three simple ideas, which together lead to an interesting outcome: -- Product Platform Architecture - firstly, a product should use a Platform Architecture in order to keep development costs low, and yet allow the product to be adapted to different local markets in Africa -- Franchise Model - the best way to achieve scale is to work with local entrepreneurs through franchising, an approach which enables allocating responsibilities and risks within the system hierarchy -- Lean Operating Model - finally, the operating entity has to be exceptionally lean by design, in order to ensure an affordable product for consumers - an idea known as a Base of the Pyramid (BOP) strategy A case study of Southern Nigeria illustrates the concept. / by Thomas Llewellin Smith. / S.M. in Engineering and Management / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program
226

Towards measuring attention allocation in model-based engineering teamwork

Manandhar, Prakash. January 2020 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, September, 2020 / Cataloged from the official version of thesis. / Includes bibliographical references (pages 93-98). / Large organizations succeed when they are operating with systemic awareness. A similar dynamic could be in effect at the level of teams and teams of teams within engineering organizations. Engineering teams are tasked with solving problems of multidisciplinary nature with multiple stakeholder constraints. For better performance, teams need to be aware of multiple constraints simultaneously. This thesis explores the design of sensors to measure team awareness using team attention in the problem and solution spaces. The concept of situational awareness and attention allocation has been studied in literature in the context of user interaction design for individuals or teams in areas where team members could be overwhelmed with information. Engineering problem solving is of a similar nature where team members have to be aware of multiple information sources and bring their attention to the right pieces of information to make decisions. To define what is "right", the concept of a problem space and solution space is defined. It is hypothesized that higher performing teams allocate their attention to systemically significant portions of the problem and solution spaces. An experiment is designed assuming that short strategy discussions are result in greater attention allocation to systemically significant portions of the problem and solution spaces. The concept of using a strategy discussion to spur creativity was based on literature in team creativity and innovation which posited that a process consisting of iterations of first divergent and then convergent thinking results in greater innovation. A model or toy problem of designing an innovation campus is chosen. Data from 50 teams spending one hour with a model exploration interface are analyzed. This problem was designed to be easily understandable in a short time by conference-goers from which a pool of volunteer participants were assigned randomly to 50 teams of 2 to 4 participants per team. Out to 50 teams, 14 teams were assigned to a control group who were instructed to perform a placebo discussion instead of a strategy discussion. Two other groups consisting of 14 and 15 teams respectively had strategy discussions at the beginning and middle of the experiment time-slot. Pareto frontier based ranking methods are used to rank team performance. The performance across different groups are compared using hypothesis testing methods. Results suggest that strategy discussions help to arrive at more effective problem-solving. These results are not statistically significant at 95% confidence level (they were significant at 85% confidence level) using a Kruskal-Wallis hypothesis, they do provide promising directions for further work. Besides directly testing the hypothesis, other observations were made on the data. One interesting observation was that teams that had strategy discussions tended to perform better as they executed more simulations, while teams that had the placebo discussion tended to perform worse as they executed more simulations. The data gathered during the experiments has not been fully analyzed due to the scope of the thesis. Further work that could be done include analyzing user interface "fingerprints" to measure attention allocation directly to test the assumption that strategy discussion during a decision making session results in higher attention allocation to systemically significant portions of the problem and solution spaces. An attempt is made at defining the concept of attention allocation, and quantitatively measuring how much of attention is allowed to systemically significant portions of the problem and solution spaces. Further work is also warranted in exploring alternate definitions and calculation of this metric. / by Prakash Manandhar. / S.M. in Engineering and Management / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program
227

Collective causality : building solution architectures with a crowd / Building solution architectures with a crowd

Fu, Carolyn Jiaming January 2017 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, 2017. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 54-55). / Traditional open innovation has operated on the assumption that by casting a wide net into the crowd, the likelihood of obtaining a desirable solution to a problem increases, due to the greater range of potential solutions that is obtained. This is typically implemented using a competitive format, where the best ideas are selected from a crowd, and the rest are discarded. Unfortunately, the drawback of such a format is that it fails to make use of the efforts behind discarded ideas. Each of these ideas represents a great deal of cognitive effort that has gone towards understanding and solving a problem, and discarding them sacrifices potentially useful insights that might be derived from ultimately unworkable solutions. This thesis explores how a more effective form of collective intelligence might be obtained - one where the half-baked solutions of many participants might be combined to produce something more effective than one participant's fully baked solution that is selected through competition. The specific format of a collaborative causal map is explored, where individuals can each contribute causes and causal links to an overall causal web, building an ever richer architecture of potential solutions (and their sub-solutions) to an overall problem. The goal is to integrate individuals' contributions such that they accumulate to an overall cohesive solution that is better than what any individual could have developed. A series of pilots are conducted to understand the group dynamics in both offline and online collaboration, and determine those factors that are material to the success of an online collaborative causal map. Such factors include how the question is framed, how users attend to others' contributions, or how users' contributions can be curated. These factors are ultimately incorporated into a prototype collaborative causal mapping website, which is developed for public use. / by Carolyn J. Fu. / S.M. in Engineering and Management
228

A maturity model for process data analytics in biopharmaceutical manufacturing

Egaña Tomic, Tomas C. January 2021 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, February, 2021 / Cataloged from the official version of thesis. Page 148 blank. / Includes bibliographical references (pages 139-147). / The Biopharmaceutical industry continues to add a record number of life-saving biological therapies every year, which builds up pressure to make their manufacturing processes faster, more consistent, and more productive. Increased digitalization is expected to address these needs by means of new capabilities related to the analysis of the data collected in the manufacturing process (a.k.a. process data analytics). The objective of this work is to research a framework with which to assess the ability of a Biopharmaceutical company to exploit process data analytics in drug substance manufacturing of monoclonal antibodies. A comprehensive view of the potential benefits of process data analytics is provided, as well as a detailed account of the improvements required to realize those benefits. The framework was built using the published information of analytics use cases, the opinions of experienced practitioners of four major biopharmaceutical companies, and other guidelines built to address similar topics in other industries. Throughout the process, a detailed account of the complexities involved in the deployment of process data analytics was captured and explained. Additionally, four approaches driving the value of analytics for biopharmaceutical processing were identified and used to classify the different use cases. The result is a maturity model of the manufacturing site that describes four archetypical states of process data analytics implementation. They are characterized in terms of the mechanics of value creation and the requirements from informational technology (IT), operational technology (OT), and external sources of information. This model provides the basis upon which biopharmaceutical manufacturers or industry consortiums can further specify its content and generate an assessment tool to guide their manufacturing strategies. / by Tomas C. Egaña Tomic. / S.M. in Engineering and Management / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program
229

An approach to developing a resilient high-speed rail enterprise architecture through digital transformation

Takagi, Ryuichi (Scientist in system design and management) Massachusetts Institute of Technology. January 2020 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, May, 2020 / Cataloged from the official version of thesis. / Includes bibliographical references (pages 136-140). / Japanese Shinkansen has been a safe and reliable mode of transportation in Japan, and JR-Central has developed a well-organized operating system architecture to ensure safety, reliability, and profitability. However, now is the time for the company to transform its architecture because the landscape surrounding the enterprise and stakeholders' needs are rapidly changing. For instance, a lifetime employment custom, which was the long-established practice in large Japanese firms, is disappearing, and the mindset of younger workers in career development can change. Digital technology, which changes general business and the way of working, is available and applicable to all industries. While the Shinkansen system has been successful thus far, the enterprise needs to develop a future architecture that fits with those trends and environments. The objective of this study is to investigate and generate a resilient Shinkansen enterprise architecture against the changes in landscape and stakeholders' needs by implementing digital transformation. The thesis uses the ARIES framework to analyze capabilities of the current enterprise architecture and identify points that require transformation. In addition, literature review and case studies are performed to identify key characteristics to proceed with digital transformation, organizational transformation, and talent management. On the basis of the analyses and literature review, this thesis generates alternative architectures that meet emerging stakeholders' needs and fit the changing landscape of JR-Central. Furthermore, the alternatives are evaluated in context of several extreme scenarios, including the worst-case scenario due to impacts from COVID-19. The results indicate that an alternative architecture that consists of small internal IT and HR units, external intrapreneurs, and corporate venture capital is the best in terms of resiliency. The thesis also provides an implementation plan for an architecting team of JR-Central. The result of this research can be utilized to design a resilient architecture to maintain its safe and reliable Shinkansen operation and create values to survive and grow in the changing landscape and uncertain future in the Japanese railway industry. / by Ryuichi Takagi. / S.M. in Engineering and Management / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program
230

Challenges in implementing cross-disciplinary design experiments in a large scale introductory physics class; a case study

Prabakar, Pushpaleela. January 2019 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2019 / Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2019 / Cataloged from PDF version of thesis. / Includes bibliographical references (page 69). / A set of new design-based physics experiments were jointly developed by the Electrical Engineering and Computer Science (EECS) and Physics departments and implemented in a large-scale, introductory physics course, 8.02 Electricity and Magnetism, at MIT. These were developed in response to student feedback indicating that overly structured experiments limit their grasp of the abstract concepts of electricity and magnetism. Consequently, each of the four in-class experiments has an open-ended, design component, exploring a practical application of the concepts. In addition, these experiments were built upon an "active learning" structure, whereby students interact with each other and with online materials during class. They were integrated into a class of >700 students, with 8 sections total (~90 per section), with pre- and post-experiment assignments to support and reinforce the material covered. After each experiment, the students were surveyed to determine their self-assessment to gauge their understanding of the purpose of the experiment and assess whether sufficient time was allocated to the experiment. At the end of the term, the students were also surveyed to compare their experience with both the traditionally highly structured experiments and the design experiments conducted during the same semester. Results revealed that though the design experiments were more enjoyable for the students, they perceived the traditional experiments as more relevant to the lecture material. Possible reasons why the students saw less connection to the lecture material might be attributed to the novelty of these experiments and some structural problems in deploying them on such a large scale. While problems associated with the adoption of new pedagogical approaches are not surprising, it is important to carefully assess the outcomes and reflect on how to address the shortcomings for the next iteration. / by Pushpaleela Prabakar. / S.M. in Engineering and Management / S.M. / S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program / S.M. Massachusetts Institute of Technology, Department of Mechanical Engineering

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