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Engineering Systems - Ph.D. / Sc.D.

Mostrando recursos 1 - 20 de 161

  1. Potential housing bubble with Chinese characteristics : analysis and policy design through an operational model

    Zhang, Xin, Ph. D. Massachusetts Institute of Technology
    This thesis analyzes the potential housing bubble in the Chinese urban housing market. Using an operational model built on system dynamics (SD), it explores the unique housing market structures, information flows, key agents and their decision-making processes, and the system constraints that may contribute to the bubble forming phenomenon. Its SD models differ from intensive data-driven economic models. They are structural, operational, and focus on causal relationships. They can more easily accommodate non-market features and unique institutional components, where long-range historical data are not readily available. As the Chinese government heavily controls its housing markets, housing prices greatly depend on...

  2. Drivers of photovoltaics cost evolution

    Kavlak, Goksin
    Photovoltaics (PV) have experienced notable development over the last forty years. PV module costs have declined 20% on average with every doubling of cumulative capacity, while global PV installations have increased at an average rate of 30% per year. However, costs must fall even further if PV is to achieve cost-competitiveness at high penetration levels and in a wide range of locations. Understanding the mechanisms that underlie the past cost evolution of PV can help sustain its pace of improvement in the future. This thesis explores the drivers of and constraints to cost reduction and large-scale deployment of PV. By...

  3. Multi-stakeholder contribution to biotechnology environmental assessment

    Lightfoot, Shlomiya
    Environmental assessments, such as those for biotechnology applications, are typically conducted by small groups of expert assessors, but scholars and practitioners are increasingly interested in involving diverse stakeholders. In addition to other reasons for broader involvement, researchers have proposed that stakeholders could substantively aid assessment by (1) contributing system knowledge; (2) applying diverse conceptual models; (3) helping available knowledge keep pace with assessment needs; and (4) contributing based on their values, as do narrow expert assessors. Hypothesizing that these types of contribution, suggested theoretically or observed in single workshops, represent key sources of stakeholder contribution across processes, this study examines...

  4. Dynamics of technology innovation and diffusion with emphasis on wind energy

    Dykes, Katherine L., 1980-
    This thesis takes an interdisciplinary look at wind energy innovation and diffusion through a historical case study and system dynamic quantitative model. The former uses a framework known as actor-network- theory (that allows technical as well social forces to shape historical outcomes) and applies it to an in-depth case study of the history of the technology throughout several époques. Rather than simplifying the story of the technology into a case of winners and losers, as past studies have done, this work demonstrates the complexity of the history of wind technology where many individuals in different countries, companies and national governments,...

  5. Supply chain financing in Developing countries

    Breitbach, Timothy W
    There is no definitive blueprint for ending poverty and increasing prosperity across the globe, but the World Bank argues that inclusive economic growth is critical to achieving global development goals. This thesis focuses on supply chain financing, and its potential to make a positive and lasting impact on people and businesses in resource-constrained environments. It seeks to develop a better understanding of how supply chain and finance structures impact profits, sales growth and risk. The two-phased research design seeks to address the gap in the supply chain and development literature on supply chain finance in small and medium sized firms...

  6. The impact of strategic investment on success of capital-intensive ventures

    Farahanchi, Ali
    Established companies in technology-enabled industries such as software, telecommunications, pharmaceuticals, and semiconductors, have used corporate venture capital as a lever to access and screen technological advances, and to drive innovation outside the traditional firm boundaries. Recent years have witnessed emergence of a new wave of corporate venture capital funds that increasingly interact and compete with traditional venture capital firms in the entrepreneurial ecosystem. The incremental benefits of financing a startup through corporate venture capital have been a subject of study by researchers across Economics, Finance, Strategy, and Innovation fields. First, this thesis examines entrepreneurs' rationale for raising capital from corporate...

  7. Improving the performance of regional electricity markets in developing countries : the case of the Southern African Power

    Rose, Amy Michelle
    Power pools can reduce the cost of providing electricity and improve system reliability through coordinated use of energy resources. Realizing these benefits requires careful market design supported by technical, economic and institutional analysis of the system as it exists today and as it will likely evolve in the future. In this dissertation, I demonstrate this integrated approach through a detailed study of the design and operation of the Southern African Power Pool (SAPP). I develop a linear programming model of the SAPP system that explicitly represents hourly system operations to conduct this analysis. This model is then adapted through the...

  8. Science to support toxics governance : tracking mercury and other pollutants from policy to impacts

    Giang, Amanda (Amanda Chi Wen)
    Persistent and bioaccumulative toxins like mercury pose unique challenges for environmental governance. The complexity of their movement through coupled social, technological, and natural systems can make it difficult to trace their path from emissions to wider impacts, as emissions and impacts can be separated both in time and space. This separation can make it difficult to assess whether different management and policy proposals will effectively reduce negative impacts. Focusing primarily on mercury, this dissertation explores how we can use interdisciplinary tools and approaches-from atmospheric modelling to community engaged research-to better trace this path from policy to human impacts, in support...

  9. Greenhouse gas equivalency metrics for evaluating energy technologies

    Edwards, Morgan Rae
    This thesis addresses a long-standing question about how to compare energy technologies that emit different types of climate forcers during their life cycles. This problem is challenging because these forcers have dissimilar lifetimes in the atmosphere, ranging from days (black carbon) to decades (methane, CH 4) to centuries or more (carbon dioxide, CO2 ). Efforts to reduce the climate impacts of energy use may involve a tradeoff between these short-and long-lived emissions. Equivalency metrics, which express emissions of one forcer (e.g., CH4 ) in units of another (typically CO2), are widely-used tools for comparing the climate impacts of emissions. These...

  10. Intellectual property and architecture : how architecture influences intellectual property lock-in

    Berardi, Christopher W. (Christopher Walter)
    Intellectual property lock-in is a wicked problem particularly pervasive under monopsony market structures, such as the Department of Defense (DoD). However, little research exists on the mechanisms of action that induce intellectual property lock-in. This work postulates the conjuncture of architecture and intellectual property is one such mechanism of action and erects a research methodology to investigate this link. This dissertation began with a review of literature, which revealed more research is needed into basic trends or estimates of magnitude for intellectual property lock-in. To quantitatively frame the magnitude of the problem an investigation was conducted into all DoD contracts...

  11. Bioenergy and its use to mitigate the climate impact of aviation

    Staples, Mark Douglas
    The use of modern bioenergy presents an opportunity to mitigate CO2 emissions contributing to anthropogenic climate change by offsetting fossil fuel use, and the work presented in this thesis contributes to the literature on bioenergy and climate change mitigation in three areas. First, this thesis quantifies the maximum potential reduction in global lifecycle greenhouse gas (GHG) emissions from the use of bioenergy to offset demand for fossil fuel-derived electricity, heat and liquid fuels in 2050. The findings indicate that bioenergy could reduce annual emissions from these end-uses by a maximum of 4.9-38.7 Gt CO2e, or 9-68%. The range of results...

  12. Locating the source of large scale outbreaks of foodborne disease

    Horn, Abigail Lauren
    Foodborne illness outbreaks impose enormous health and economic burdens in the US. Identifying the origin of the contaminated food causing an outbreak is a challenging problem due to the complexity of the food supply and the absence of coherent labeling and distribution records. Current investigative methods are slow, resource intensive, and the overwhelming majority of investigations are unsuccessful in identifying the location source of an outbreak. New tools and approaches that take advantage of modern data and analytical techniques are needed to more quickly identify outbreak origins and prioritize response efforts. The practical objective of this work is to improve...

  13. Combining tradespace exploration with system dynamics to explore future space architectures

    La Tour, Paul A. (Paul Alexis)
    This work proposes a merger of Tradespace Exploration with System Dynamics modeling techniques in a complementary approach. It tests the value of this mixed method for modeling the multiplicity of inputs and complexity of feedback loops that affect the cost, schedule and performance of satellite constellations within the Department of Defense. The resulting simulation enables direct comparison of the effect of changing architectural design points and policy choices with respect to satellite acquisitions and fielding. A generation-over-generation examination of policy choices is made possible through the application of soft systems modeling of experience and learning effects. The resulting model enables...

  14. Modeling human attention and performance in automated environments with low task loading

    Gao, Fei, Ph. D. Massachusetts Institute of Technology
    Automation has the benefit of reducing human operators' workload. By leveraging the power of computers and information technology, the work of human operators is becoming easier. However, when the workload is too low but the human is required to be present either by regulation or due to limitations of automation, human performance can be negatively affected. Negative consequences such as distraction, mind wandering, and inattention have been reported across many high risk settings including unmanned aerial vehicle operation, process control plant supervision, train engineers, and anesthesiologists. Because of the move towards more automated systems in the future, a better understanding...

  15. Accounting for non-hazardous industrial waste in the United States

    Krones, Jonathan Seth
    This dissertation presents a method for estimating the tonnage and composition of non-hazardous industrial waste (NHIW) flows in the United States. For thirty years, it has been an accepted fact that NHIW is generated at a rate of 6.9 billion Mg per year, making it the largest waste flow in the country by more than an order of magnitude. However, this value was generated in 1985, has not been updated since, and is thought to account largely for the weight of dilute process water disposed in surface impoundments rather than solid waste generated by industry. To address this data gap,...

  16. Model use in sustainability negotiations and decisions

    Czaika, Ellen Gail
    Sustainability negotiations and decisions require the integration of scientific information with stakeholder interests. Mathematical models help elucidate the physical world and therefore may orient the negotiators in a shared understanding of the physical world. Many researchers suggest collaborative modeling to facilitate integrating scientific information and stakeholder interests. In this thesis, I use methods that enable repeated instances of the same decision; the exploration of alternatives to model use (e.g. learning of a model's logic, relevant information, or irrelevant information); and the exploration of alternatives to collaborative modeling (e.g. using an expert model or not using a model). This thesis comprises...

  17. Negotiated collaboration : a study in flexible infrastructure design

    Sakhrani, Vivek A. (Vivek Ashok)
    This thesis frames design in infrastructure public-private partnerships (P3s) as an exercise in negotiated collaboration. I investigate whether the collaborative design process in P3s can systematically deliver the benefits of innovation in design. The focus is on two aspects of the design process: project co-design, and collaboration mechanism. I find that both aspects enable innovation by driving project actors to learn about the design space and develop a shared understanding of the design problem. Learning through shared understanding not only improves quantifiable payoffs (Objective Value) but also enhances the actors' psycho-social outcomes (Subjective Value). Co-design is a process in which...

  18. Using inclusive wealth as a measure of sustainability for infrastructure planning and evaluation

    Collins, Ross D. (Ross Daniel)
    Inclusive wealth (IW) measures the productive base of an economy, which is a linear index of its capital asset stocks. Changes to IW per capita over time track changes to intergenerational human well-being, thus non-declining IW per capita indicates sustainable development. National IW has only been measured retrospectively; this dissertation models and projects IW prospectively, measuring the impact of alternative infrastructure plans on IW. The focus of the work is on electricity planning in oil-exporting countries. Domestic oil consumption in these countries, driven by increasing electricity use, threatens long-term development by reducing the export revenue on which the government and...

  19. Strategies to reduce product waste in the consumer packaged goods industry

    Akkas, Arzum, 1978-
    The cost of waste for products such as soft drinks, shelf stable dry food, and dairy in the consumer packaged goods industry is massive, about $15 billion annually in the U.S.A. This thesis focuses on waste associated with product expiration since this type of waste involves both manufacturers and retailers as well as different functional areas such as production, warehousing, sales, procurement, and store operations. As a result, the industry has not made much progress in reducing this type of waste. We study three problems related to product expiration. Chapter 2 presents a descriptive study examining the root causes of...

  20. Innovation strategy to sustain a technological edge for national security & global leadership

    Srivastava, Tina Prabha
    The United States' global lead in secure technology innovation is a cornerstone of national defense. Breakthroughs in technology are critical in establishing and maintaining military superiority. Technology innovation strategies enable the U.S. to maintain this superiority by effectively yielding innovation from R&D investment. However, these strategies must evolve within increasing financial pressures, technological complexities, and dynamic geo-political conditions. Through an analysis of the innovation landscape and development of a taxonomy of open innovation, this dissertation shows that emergent open technology innovation strategies (OTIS) have been successfully applied in the commercial sector, and, after analyzing the relevant metrics, establishes that OTIS...

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