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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.
71

Understanding the value proposition unmanned aerial systems provide during the phases of the crop Cycle

Walters, Tobias J January 2015 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2015. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 73-77). / Increasing crop productivity is a challenge as old as human history. Advancements in technology have allowed farmers to produce ever-increasing amounts of food on a given amount of land. With the world's population expected to reach roughly nine billion by 2050 (United Nations 2013), the demand for food will require increasingly improved methods of agricultural production. One of these potential methods is the use of unmanned aerial vehicles (UAVs) to monitor crop health and identify potential issues. This thesis will explore how current stakeholders plan to utilize this technology and the perceived value they believe it will deliver across the various phases of the crop cycle. This thesis begins by reviewing modem precision agriculture management practices and discussing how remote sensing plays a role in improving the efficiency of these types of farming methods. It also identifies a number of challenges facing the industry to include the impact of current regulations on the market. This thesis develops a stakeholder value network that clarifies the tangible and intangible value exchanges between the focal organization and its stakeholders. As well as constructing an OPM (Object Process Methodology) model to describe the system and demonstrate the stakeholder interactions and system process and sub-process decomposition. It also provides visual display of how the value is delivered across these processes. The final aspect of the research for this thesis is to identifies the lead users for these systems and determines how they measure the value of the data provided by UAVs for remote sensing and crop management decisions in support of farming operations. The value proposition for the various crop phases and the ideal uses cases discussed by lead users in this thesis may be used to guide future research in agriculture technology development, and drive further innovation in the emerging field of commercial unmanned aerial system use. / by Tobias J. Walters. / S.M. in Engineering and Management
72

Improving e-Commerce sales using machine learning / Improving electronic-commerce sales using machine learning

Thobani, Shaheen January 2018 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2018. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 68-70). / Trends show promising growth of the online e-Commerce industry. While the e-Commerce companies are aggressively moving towards digital sales and marketing, the customers are being bombarded with frequent and often irrelevant marketing communication from myriad sources. The thesis proposes understanding the digital purchase journeys of the customers from the lenses of both sellers and customers to make online sales and marketing efforts relevant and intelligent. The thesis applies the improved customer journey framework to identify the needs of the customers and goals of the seller at various stages of customer purchase journey. It discusses the need to take an integrated view of the purchase journey to improve the customer experience at the journey level. It illustrates with an example how to design end-to-end journeys - a starting point for consciously shaping the purchase journeys. Larger companies are using Machine Learning to improve marketing technologies and processes to create a competitive advantage and capture market share through digital presence. The thesis aims to understand and illustrate the applications of Machine Learning to digital sales and marketing ecosystem for the e- Commerce industry. It first understands the e-Commerce touchpoints using which customers interact with the brands and delves deeper into the underlying technologies powering these touchpoints. Then it illustrates and analyzes the application of Machine Learning to the e-Commerce website which includes search, recommendation system, and Product Detail Page with an aim to improve conversion, and to the advertising ecosystem which includes Data Management Platform and Demand Side Platform in order to enable prospecting and customer targeting. The thesis also illustrates and proposes the use of a framework called 'Machine Learning Canvas' to systematically apply Machine Learning to any system while keeping value proposition for the business in the center. / by Shaheen Thobani. / S.M. in Engineering and Management
73

Teamwork behaviors at mesoscale : meaningful explorations of tradespace during project design

Tan, Puay Siang January 2018 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2018. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 112-113). / The increasing complexity in Systems of Systems requires Teams of Teams (TofT) from different functional domains to work together. Rather than focusing on individuals and teams (the microscale) or total projects and portfolios (the macro-scale), this research aims to better detect and understand the teamwork behaviors at the meso-scale, the behaviors and interactions amongst the team of teams. Using the Project Design approach, Design Groups representing a TofF participated in a model- based simulation experiment to reduce the cost and duration of an implementation project for an autonomous vehicle. Design Groups were provided specific instructions to either inhibit or promote communications as they worked together to make changes to the Project Model of the autonomous vehicle, after which they can perform simulation to obtain the project outcome in terms of cost and schedule. In this experiment the teamwork was instrumented, detecting attention allocation, changes, and resulting exploration of the project tradespace. A quantifiable ranking methodology was developed to evaluate the performance of the Design Groups based on the iterations made as they explored and simulated the project model. This methodology ranked the Design Group by 1) higher number of outcomes obtained at the Pareto Frontier of the tradespace and 2) outcomes in earlier Pareto Frontiers. Two indicators of Team Performance - Number of Iterations and Communications Behaviors of the Design Group - were studied where correlations were found to be weak. Tree Diagrams were generated to visualize the tradespace exploration of the Design Group by mapping the iterations performed in sequence and provided details on the changes type made to the project model. A Chunking Process dovetailed the Tree Diagrams to detect the meaningful explorations of the tradespace by each Design Group. Each Meaningful Exploration was segmented into "Chunks" which were further classified into blocks with specific number of changes. This study provided further insights on the coherence in which changes were made along the path of tradespace explorations. Information from the Chunking Process is used to determine how "focused" the Design Groups were in the decision making process. Three ratios were suggested, namely, Ratio of Focus Score to Total Iterations with Changes, Ratio of Focused Iterations to Total Iterations with Changes and Ratio of Meaningful Changes Block to Total No of Chunks. The research concludes with using these ratios as an indicator of coherence and potential sensors to detect presence of strategy in teams in future experiments. The key insights from this research is that the Project Design Approach provides the same baseline project model for all Design Groups that enables a fair and quantifiable ranking of team performance. In instrumenting the experiment, collective group responses to qualitative data is preferred over individual responses for a more representative analysis of the teamwork behaviors. Another insight is that tradespace explorations by the Design Groups do not occur in unilateral fashion. Thus, it is important to have a visual image of the changes made along the tradespace exploration to identify the meaningful exploration paths. Segmenting these meaningful exploration paths provides the means for measuring coherence of the Design Groups in their decision making process. Next steps for future experiments include embedding in the Project Design software to collect the group responses required for quantitative analysis as the experiment is on-going. The measurement of team learning effects is suggested for future research by having a two-step data collection process in which the same experiment can be conducted as a first step and having the same participants to repeat another Project Design Challenge several months later in the second step to evaluate the team performance. / by Tan Puay Siang. / S.M. in Engineering and Management
74

Safety-guided design & analysis of space launch vehicles / Safety-guided design and analysis of space launch vehicles

Rising, John M. (John Michael) January 2018 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2018. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 103-108). / The advent of commercial launch systems has brought about a new age of space launch vehicle design. In order to survive in a competitive market, space launch providers must design systems with new technologies in shorter development times. This changing nature of space launch vehicle design requires a new way to perform safety analysis. Traditional hazard analysis techniques do not deliver adequate insight early in the design process, when most of the safety-related decisions are made. Early design decisions are often made using "lessons-learned" from previous launch systems, rather than interactive feedback from the new vehicle design actually being developed. Furthermore, traditional techniques use reliability theory as their foundation, resulting in the use of excessive design margin and redundancy as the "default" vehicle design choices. This equivocation of safety and reliability may have made sense for simpler launch vehicles of the past, but most modern space launch vehicle accidents have resulted from incorrect software specifications, component interaction accidents, and other design errors independent of the reliability of individual components. The space launch industry needs safety analysis methods and design processes that identify and correct these hazards early in the vehicle design process, when modifications to correct safety issues are more effective and less costly. This work shows how Systems-Theoretic Process Analysis (STPA) can been used as a powerful tool to identify, mitigate, and possibly eliminate hazards throughout the entire space launch vehicle lifecycle. This work begins by reviewing traditional hazard analysis techniques and the changing nature of launch vehicle accidents. Next, it describes how STPA can be integrated into the space launch vehicle lifecycle to design safer systems. It then demonstrates the safety-guided design of a small-lift launch vehicle using STPA. Finally, this work shows how STPA can be used to satisfy regulatory and range safety requirements. The thesis of this work is that integration of STPA into the design of space launch vehicles can make a significant contribution to reducing launch vehicle accidents. / by John M. Rising. / S.M. in Engineering and Management
75

Organizing for radical inclusion : reflections from hackathons

Punjwani, Fahad January 2018 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2018. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 36-37). / Despite moving the world forward, technological progress has left many people behind. Science and technology industries see themselves as open to all. Yet, they lack inclusion: not involving and empowering people across a range of human differences. Hackathons are a microcosm of these industries and suffer from a similar problem. By examining hackathons, we can uncover principles for creating, what I call, radical inclusion. Radical inclusion is the interbeing with all, seeing our realities and existence as interwoven. However, existing social systems hinder radical inclusion. Thus, we have to be diligent in removing these barriers. Put simply, we have to organize for radical inclusion. This thesis is a reflection of my lived experiences and secondary research and an investigation of ways to organize for radical inclusion. It includes lessons learned from organizing, attending, and studying hackathons and analogous experiences. These lessons culminate into five principles that ensure that a hackathon is radically inclusive. This research has revealed five principles that can create and cultivate radical inclusion: ** Radical inclusion is not a default social state today. Be intentional about being radically inclusive. Make it an imperative for all in an organization. ** Radical inclusion is uncomfortable. Honor this discomfort and empower organizing team and participants to navigate such situations. ** Radical inclusion necessitates meeting people where they are, as they are, in their journeys. Embody deep hospitality with wide open arms to all. ** Radical inclusion comes from encouraging human transformation, a continuous process. Foster patience and encourage forgiveness for self and others. ** Radical inclusion is rooted in a ruthless search for truth. Enable all to be soft bellied: to let personal guards down. This nurtures curiosity to explore and be moved by the truth of the other. / by Fahad Punjwani. / S.M. in Engineering and Management
76

Dilemma of speed vs. scale in software system development best practices from industry leaders

Kumar, Kshitij 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 90-93). / Many startup organizations face a dilemma as they scale up and their systems grow more complex. This dilemma is between the speed of releases i.e. agility and the scalability of their systems, reflected in the performance, stability and maintainability of their systems as they become larger. A startup is typically very nimble and releases new features and updates to its product very quickly. However, as a startup grows bigger the frequency of releases typically tends to go down. A similar phenomenon is observed in case of incumbent organizations, those that are old, large and complex, and that already have systems at scale; they have systems that perform at scale, and are stable and maintainable, but the pace of development is slow, and it find it hard to speed up their release cycles. Through the study of organizations that have successfully reconciled the required and coveted scalability along with speed as these organizations moved from being small startups to become larger, this study demonstrates that speed vs scale is a dilemma for startups that can be reconciled as they scale up, because there are a set of practices such as modular architecture choices, minimizing work in progress by adopting frequent deployments, automation in testing and utilizing innovative management techniques, which can enable startup organizations to scale up their system and maintain high speed. Although the study of incumbents as they try to speed up while maintaining their scalability is outside the scope of this work, this study also presents a hypothesis for further investigation that it may also be possible for incumbent organizations to speed up at large scale, by embracing these practices. / by Kshitij Kumar. / S.M. in Engineering and Management
77

A framework of methods and process improvements to better align technology development with DoD space enterprise priorities

Cantu, Kathryn R January 2016 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, 2016. / "September 2016." Cataloged from PDF version of thesis. / Includes bibliographical references (pages 94-100). / Strong research and development planning is critical to ensuring the necessary technologies have been matured for future acquisition programs. For the DoD Space Enterprise, research and development occur across a myriad of government laboratories, Federally Funded Research & Development Centers, other government agencies, academia, and industry. This work is governed through many different processes, but improvements could be made to the communication, collaboration, cooperation, and coordination through a well aligned governance structure. The use of Model-Based Systems Engineering, Technology Roadmapping, and Design Structure Matrices can transition the DoD to an approach that documents the capability needs, priorities, timelines, and system interdependencies in a way that facilitates knowledge sharing and cooperative, coordinated system planning. This process would begin by developing a solution-neutral functional architecture and decomposing the technology needs against the planned future acquisition timelines in a technology roadmap that integrates all space mission areas. A streamlined process with distinct functions, each chaired by a single enterprise authority, executed by a space community chief architect, and with participation by the relevant stakeholders, can lead to a portfolio management process that aligns technology development with enterprise priorities. The integrated roadmap can be used to communicate transparently with all R&D entities so that investment decisions can be aligned with the future acquisition needs. This approach will take best advantage of the incredible research that is occurring throughout the country for space systems, and ensure that the right technology is being shepherded for on-orbit demonstration at the right time. / by Kathryn R. Cantu. / S.M. in Engineering and Management
78

Obesity & overweight epidemic : an innovative approach to understanding & addressing obesity In the Kingdom of Saudi Arabia / Obesity and overweight epidemic : an innovative approach to understanding and addressing obesity In the Kingdom of Saudi Arabia / Innovative approach to understanding & addressing obesity In the Kingdom of Saudi Arabia

Al-Tayyar, Ahmed H January 2017 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, 2017. / Page 129 blank. Cataloged from PDF version of thesis. / Includes bibliographical references (pages 115-122). / Obesity and overweight are complex global issues that have been and continue to be a significant problem that needs to be addressed. Understanding obesity and overweight are fundamental to finding practical and sustainable solutions. Innovation has different meanings to different people and can be applied in many different sectors in varying forms and at different levels. Innovation in healthcare is no longer a luxury but rather a necessity. In this thesis, we review some concepts of interest to healthcare innovation briefly and also examine the topic of obesity and overweight from a global perspective and with a focus on the Kingdom of Saudi Arabia. We review global obesity and overweight and then focus on obesity and overweight in the Kingdom of Saudi Arabia. We also reflect on the work of Prof. Clayton Christensen "Jobs to be Done Theory" and how it can help address innovation in the healthcare system and in particular applying it to the general concept of tackling obesity. The thesis highlights a critical understanding of obesity based mostly on the work of Jason Fung, MD in his recent book titled "The Obesity Code: Unlocking the Secrets of Weight Loss." A novel integrated solution for tackling obesity in the Kingdom of Saudi Arabia will be proposed incorporating insights from the research material on both innovation and obesity with the utilization of concepts gained from the System Design and Management program at MIT. The concept of innovation in the healthcare setting is shown to be instrumental in creating an opportunity for higher quality, cheaper and faster delivery of health services heavily dependent on the work of Prof. Clayton Christensen. Also, we highlight the need for an innovative integrated solution at different levels of the system including the individual level and institute level and finally the national levels. We believe there is a genuine need to approach innovation in the healthcare setting at the different establishments within the healthcare system and the importance of cross-pollinated innovation teams. / by Ahmed H. Al-Tayyar. / S.M. in Engineering and Management
79

A system approach to implementation of predictive maintenance with machine learning

Ye, Chen, S.M. Massachusetts Institute of Technology January 2018 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2018. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 87-91). / Digital technology is changing the industrial sector, yet how to make rational use of some technologies and create considerable value in a variety of industrial scenarios is an issue. Many digital industrial companies have stated that they have helped clients with their digital transformation, create much value, but the real effects have not been shown in public. Venture capitals firms have made huge investment in potential digital industrial startups. Numerous industrial IoT platforms are emerging in the market, but a number of them fade soon after. Many people have heard about industrial maintenance technology, but they have difficulty in differentiate concepts such as reactive maintenance, planned maintenance, proactive maintenance, and predictive maintenance. Many people know that big data and Al are essential in industrial sector, but they do not know how to process, analyze, and extract value from industrial data and how to use Al algorithms and tools to implement a research project. This thesis analyzes the entire digital industrial ecosystem in various dimensions such as initiatives, technologies in related domains, stakeholders, markets, and strategies. This work also analyzes of the predictive maintenance solution in various dimensions such as background, importance, suitable scenarios, market, business model, and technology. The author plans an experiment for the predictive maintenance solution, including goal, data source and description, methods and steps, and flow and tools. Then author uses a baseline approach and an optimal approach to implement the experiment, including data preparation, selection and evaluation of both regression and classification models, and deep learning practice through neural network building and optimization. Finally, contributions and expectations, and limitations and future research are discussed. This work uses a system approach, including system architecting, system engineering, and project management, to complete the process of analysis, design, and implementation. / by Chen Ye. / S.M. in Engineering and Management
80

Systems theoretic process analysis applied to Air Force acquisition technical requirements development

Summers, Sarah E January 2018 (has links)
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2018. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 183-184). / The Air Force experienced 12 Class A aviation mishaps in 2016, which resulted in 16 fatalities and 9 destroyed aircraft. So far in 2017, The Air Force has again experienced 12 Class A mishaps with 5 fatalities and 7 destroyed aircraft. (1) In addition to these mishaps, development of new aircraft or modifications to aircraft often take well over the planned duration. Developmental test identifies design deficiencies that must be addressed before the aircraft is fielded, which requires expensive and lengthy redesign cycles. A systems approach to design with humans included as part of the system can improve both the development process and aviation safety. Such an approach was created by Professor Nancy Leveson at MIT and is called Systems Theoretic Process Analysis (STPA). STPA is shown to be applicable to the Air Force acquisitions process throughout the product lifecycle. STPA is also compliant with the airworthiness handbook, MIL-HDBK-516C, and STPA documentation is beneficial to the airworthiness certification inspectors. STPA is applied to two use cases. One is a conceptual JSTARS aircraft, and the other is an unmanned aerial vehicle (UAV) that was modified from a general aviation aircraft. The Air Force is currently in source selection for a replacement to the JSTARS aircraft. The high-level STPA analysis is for a functional replacement to the JSTARS aircraft, as would be needed early in the acquisitions process. Additionally, accidents, hazards, and a safety control structure are developed for the JSTARS support system. The UAV analysis is more detailed, and provides information that is necessary during the Technology Maturation & Risk Reduction phase of an acquisition process. / by Sarah E. Summers. / S.M. in Engineering and Management

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