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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.

Stakeholder collaboration in Air Force acquisition : adaptive design using system representations

Dare, Robert E. (Robert Ernest), 1961- January 2003 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology, Management, and Policy Program, 2003. / Includes bibliographical references (p. 308-311). / Air Force development of new or evolutionary weapon systems is a complex endeavor due to the involvement of many stakeholders and the presence of considerable uncertainty in the acquisition environment. The ability to adapt a weapon system while it is still being designed affords a means to respond to this complexity. The fundamental motivation for this research is to discover how Air Force development programs, operating within established constraints, can improve their adaptability during the design phase to provide more value to the warfighter. The thesis of this research is that the quality and nature of collaboration between stakeholders during the design phase of weapon system development programs determines how effectively they share knowledge, which in turn drives the level of program adaptability. Eight case studies were conducted on Air Force development programs. Data were collected on collaborative practices and patterns of adaptability demonstrated during design. The research placed an emphasis on usage of "system representations" such as prototypes and beta software releases that acted as a form of boundary object to facilitate knowledge sharing across organizational boundaries. As programs used system representations to provide higher levels of knowledge sharing, they were found to be more adaptable. System representations were more effective at promoting adaptability when they represented the design with higher fidelity, providing system-level detail and covering stakeholder emphasis areas. Lastly, certain key stakeholder roles were found to contribute both flexibility and structure, facilitating a "zone of novelty" in which the stakeholders could exercise creativity and evaluate design options while still executing the program within established constraints. / (cont.) This research indicates that the pressing need for Air Force programs to be able to adapt in today's uncertain acquisition environment can be addressed to a significant degree through the usage of effective system representations in conjunction with supporting patterns of stakeholder interaction. Specific recommendations for Air Force acquisition policy makers and practitioners are provided. / by Robert E. Dare. / Ph.D.

Understanding and applying the concept of sustainable development to transportation planning and decision-making in the U.S.

Hall, Ralph P. January 2006 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology, Management, and Policy Program, 2006. / Includes bibliographical references. / This research demonstrates that sustainable development is a multidimensional concept that should be approached in a transdisciplinary manner. Its objective has been to synthesize and integrate disparate and currently unconnected lines of thought that have not yet been applied in a systematic way to promote sustainable development and sustainable transportation. The primary contribution of this research is the theoretical development of a decision-support framework that identifies the tools and approaches that decision-makers could/should use to create policies and programs that transition society towards sustainability. These tools and approaches are either articulated or developed by the author throughout the dissertation. Specific ideas explored include a Rawlsian/utilitarian decision-making philosophy; a hybrid trade-off/positional analysis framework that is presented as an alternative to benefit-cost analysis; ecological vs. environmental economics; participatory backcasting; and ways to stimulate disrupting and/or radical technological innovation. To identify gaps that exist between theory and practice, the approach embodied in the proposed sustainable transportation decision-support framework is compared with current metropolitan transportation planning and decision-making processes in the U.S. The framework is then used to consider how the U.S. federal government might move the nation's transportation system towards sustainability. / by Ralph P. Hall. / Ph.D.

Command in air war : centralized vs. decentralized control of combat airpower

Kometer, Michael W January 2005 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology, Management, and Policy Program, 2005. / Includes bibliographical references. / This study answers the question, "What has been the impact of the Information Age on the Air Force's doctrinal tenet of "centralized control and decentralized execution?" It traces the evolution of command and control of airpower through operations Desert Storm, Allied Force, Enduring Freedom, and Iraqi Freedom and compares its practice with classic theories established by Huntington, Cohen, Van Creveld, and Air Force doctrine. In the absence of a peer superpower in the 1990s, U.S. decision-makers often resorted to the use of detailed constraints to gain direct influence on military operations. The more detailed the constraints from the strategic level, the closer the theater military commander held authority for planning air strikes, and the less proactive the air component was in coordinating with other components. The Air Force developed the Air Operations Center (AOC) to put together battlespace information; it is not yet possible to do this at lower levels, so the AOC has become dominant in controlling air operations. Initially resistant to get involved in ongoing missions, commanders found the AOC was needed to accomplish some "time-sensitive targeting" missions; however, they have also learn to delegate to speed up the processes. / (cont.) But the insertion of the AOC into ongoing operations also led to distribution of tasks-where before the aircrew had performed the whole "kill chain" sequence, now the aircrew often performed only the end game tasks. This distribution could increase the potential for system accidents because people tend to drift from procedures during slack times and thus to be disintegrated when the system becomes tightly coupled. Technology has not changed the fundamental principles of command and control. The information, telecommunications, sensor and weapons technology have altered the way these humans perform their jobs, and even the jobs they perform. But commanders still need to cultivate a learning organization. Uncertainty and the coupling of diverse organizations still require that they balance empowerment with accountability by developing depth in the command relationships among their subordinates. Commanders can best gain this depth through deliberate delegation, a bruising debate, and assessment of results rather than management of specific details. / by Michael W. Kometer. / Ph.D.

New venture commercialization of clean energy technologies

Miller, David S. (David Seth) January 2007 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology, Management, and Policy Program, 2007. / "June 2007." / Includes bibliographical references (p. 245-250). / Clean energy technologies lower harmful emissions associated with the generation and use of power (e.g. CO2) and many of these technologies have been shown to be cost effective and to provide significant benefits to adopters. Examples of clean energy technologies include renewable and/or efficient distributed generation (e.g. solar, wind, geothermal, fuel cells, cogeneration); energy efficiency technologies; intelligent energy management; efficient energy storage; green building technologies; biofuels; and ancillary products and services that reduce emissions associated with power generation, transmission and distribution. This thesis examines why new ventures founded to commercialize these technologies have failed to achieve widespread adoption. Based on interviews with clean energy entrepreneurs and other stakeholders and on case studies of clean energy technology ventures, a new venture simulation model was developed that models the cash flow, labor force, market, competition, and product development for a prototypical clean energy technology venture. When the model is parameterized to correspond to a venture that starts with superior technology at an attractive price its behavior corresponds to the experience of many of the companies interviewed. / (cont.) The modeled venture takes many years to achieve profitability due to long sales cycles, limits to market growth, and the time needed to gain experience producing and selling its products, and therefore has a high probability of failure. Analysis of the model results in a set of guidelines for what these ventures, investors, and policy makers should do to increase their odds of success. The venture is better off starting with more sales and marketing personnel and expertise rather than engineers, and should develop no more product features than are necessary to sell the product. The venture should forego recurring revenue and instead receive payments up front whenever possible. A single initial equity investment in the venture is considerably more valuable than a series of investments. Government policies that raise the cost of carbon emissions; reduce barriers and increase incentives for adoption of clean energy technologies; and subsidize the development of these technologies can greatly increase the growth of these ventures and the odds of success. / by David S. Miller. / Ph.D.

Probabilistic risk analysis of restructured electric power systems : implications for reliability analysis and policies

Felder, Frank Andrew January 2001 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, Technology, Management, and Policy Program, 2001. / Includes bibliographical references (p. 193-209). / Modem society requires reliable and safe operation of its infrastructure. Policymakers believe that, in many industries, competitive markets and regulatory incentives will result in system performance superior to that under command-and-control regulation. Analytical techniques to evaluate the reliability and safety of complex engineering systems, however, do not explicitly account for responses to market and regulatory incentives. In addition, determining which combination of market and regulatory incentives to use is difficult because policy analysts' understanding of complex systems often depends on uncertain data and limited models that reflect incomplete knowledge. This thesis confronts the problem of evaluating the reliability of a complex engineering system that responds to the behavior of decentralized economic agents. Using the example of restructured and partially deregulated electric power systems, it argues that existing engineering-based reliability tools are insufficient to evaluate the reliability of restructured power systems. This research finds that electricity spot markets are not perfectly reliable, that is, they do not always result in sufficient supply to meet demand. General conclusions regarding the reliability of restructured power systems that some economic analysts suggest should be the basis of reliability policies are either verified or demonstrated to be true only when applied to extremely simple and unrealistic models. New generation unit and transmission component availability models are proposed that incorporate dependent failure modes and capture the behavior of economic agents, neither of which is considered with current adequacy techniques. / (cont.) This thesis proposes the use of a probabilistic risk analysis framework as the foundation for bulk power-system-reliability policy to replace existing policy, which is an ad hoc mixture of deterministic criteria and risk-based requirements. This thesis recommends distinguishing between controlled, involuntary load curtailments and uncontrolled, involuntary load curtailments in power system reliability modeling. The Institute of Electrical and Electronics Engineers (IEEE) Reliability Test System is used to illustrate the possible impact that dependent failure modes and the behavior of economic agents have on the reliability of bulk power systems. / by Frank A. Felder. / Ph.D.

Modeling paper material flows and recycling in the US macroeconomy / Modeling paper material flows and recycling in the United States macroeconomy

Taylor, Henry F. (Henry Farrar), 1964- January 1999 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Sloan School of Management, Technology, Management, and Policy Program, 1999. / Includes bibliographical references (p. 439-442). / Recycling, especially paper recycling, has become a de-facto public policy during the last three decades of the 20th Century. At the cusp of the new millennium it receives widespread support. Unfortunately, at the same time, this well-intentioned and locally rational action has also been soundly criticized based on the observed market instabilities in the industry that are the cause of poor performance by firms. This poor performance, especially in the case of paper, threatens the value and usefulness of recycling as an environmental strategy. Many current works that address recycling issues fail to recognize that the basis for the behavior, problematic or otherwise, is the linked set of markets that cause the materials, in the form of products and by-products, to flow through the entire macroeconomy. The sources of this behavior include both the internal structure of the sectors from which the markets are comprised as well as the linkages between the markets. To understand the potential problems in the paper recovery and associated markets and to assess remedies, this thesis develops and explores a new, integrated, macroeconomic model using the system dynamics method. The model is calibrated to paper material-flow-related data. It replicates problematic behaviors in the paper market, and describes their genesis, and forecasts their effects for the future. Analyses undertaken with the model also describe outcomes from several different commonly proposed interventions in terms of market stability, production, profitability, resource utilization, and overall recovery. / by Henry F. Taylor, III. / Ph.D.

Infrastructure investment and policy management of water resources for small-scale irrigated agriculture

Amornvivat, Sutapa, 1974- January 2003 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology, Management, and Policy Program, 2003. / This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. / Includes bibliographical references (leaves 157-167). / We investigate the options for enhancing the welfare of small farmers in Thailand through subsidies of irrigation infrastructure. Enhanced water storage and irrigation can significantly improve yield and the welfare of the farm community by providing a more reliable water supply during growing periods. Generally speaking, such enhancements require subsidies from the government or other organizations since farmers are not able or willing to finance infrastructure development themselves. In order to maximize the effectiveness of such subsidies it is important to understand how farmers will react to alternative policies. We develop a two-tier approach to this problem. First, we use a government-level optimization model to identify the set of subsidies and water pricing policies that maximizes a stated measure of aggregate social welfare. This government-level model relies on a farm-level model that determines how individual small farmers will react to the policy alternatives. The farm-level model combines hydrologic, economic, and agronomic features since it considers how hydrologic variability affects crop yield, which in turn affects the farmer's utility. Policy decision variables considered in the government subsidy/pricing model include 1) water price and the number of farms served by public storage facilities (i. e. a water supply reservoir and enhanced in-stream storage), 2) maximum sizes of on-farm ponds paid for by the government, and 3) amounts of direct cash subsidies paid to the farmer. The objective is to maximize the aggregate welfare of all farmers served subject to a limit on the total subsidy as well as constraints designed to limit inequities and urban migration. The problem is solved with a deterministic nonlinear programming algorithm. / (cont.) Decision variables considered in the farm-level model include 1) whether or not to accept a government-subsidized on-farm pond (which reduces land available for cultivation), 2) how much to consume in each year, 3) whether to devote time to agriculture or off-farm employment, 4) type of crop and irrigation technique, and 5) amount of water purchased from communal storage facilities. The problem is solved using a finite-horizon discrete-time stochastic programming algorithm. Our modeling approach is tested on a study site in Saraburi Province, Thailand. This site serves as a suitable prototype because of its existing irrigation infrastructure, relatively developed market institutions, secure land-use rights, and weak endowment of water resources. To achieve an economic optimum in which the farmers' aggregate utility of consumption is maximized, the government must provide some farmers with free reservoir water. The remaining farmers, however, help pay for the subsidy at a relatively high price. Consequently, the latter seek urban employment during the dry seasons. This cross-subsidy solution resulting from the social optimum criteria is economically efficient yet markedly inequitable. In order to assure equity, the government should construct the reservoir and sell the storage water at the same price to all farms. However, this solution cannot prevent urban migration ... / by Sutapa Amornvivat. / Ph.D.

Stakeholder-assisted modeling and policy design for engineering systems

Mostashari, Ali, 1974- January 2005 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology, Management, and Policy Program, 2005. / Page 462 blank. / Includes bibliographical references. / There is a growing realization that stakeholder involvement in decision-making for large- scale engineering systems is necessary and crucial, both from an ethical perspective, as well as for improving the chances of success for an engineering systems project. Traditionally however, stakeholders have only been involved after decision-makers and experts have completed the initial decision-making process with little or no input from stakeholders. This has resulted in conflict and delays for engineering systems with brilliant technical designs that do not address the larger context of the broader social goals. One of the fears of experts is that the involvement of stakeholders will result in technical solutions that are of poor quality. The hypothesis of this research is that an effective involvement of stakeholders in the decision-making process for engineering systems from the problem definition stage through the system representation can produce a system representation that is superior to representations produced in an expert-centered process. This dissertation proposes a Stakeholder-Assisted Modeling and Policy Design (SAM-PD) process for effectively involving stakeholders in engineering systems with wide-ranging social and environmental impact. The SAM-PD process is designed based on insights from existing engineering systems methodologies and alternative dispute resolution literature. Starting with a comprehensive analysis of engineering systems methodologies, the role of experts in engineering systems decision-making and existing stakeholder involvement mechanisms, this research explores the role of cognitive biases of engineering systems representation through actual experiments, / (cont.) and concludes that the process of defining a system through its boundaries, components and linkages is quite subjective, and prone to implicit value judgments of those participating in the system representation process. Therefore to account for stakeholder interests, concerns and knowledge in engineering systems decision-making, it is important to have a collaborative process that enables stakeholders to jointly shape the problem definition and model outputs necessary for decision-making. Based on insights from the literature, this research developed a collaborative process for engineering systems decision-making, and explored its merits and drawbacks in applying it to the Cape Wind offshore wind energy project involving actual stakeholders in the system representation process. It further explored the potential application of such a process to the Mexico City transportation/air pollution system and the Cape and Islands Renewable Energy Planning project. The Cape Wind case study showed that a stakeholder-assisted system representation was superior to the equivalent expert-centered system representation used by the permitting agency as a basis for decision-making, in that it served as a thought expander for stakeholders, captured some effects that the expert-centered representation could not capture, better took into account social, economic and political feasibility and was more useful in suggesting better alternative strategies for the system. The case studies also highlighted the importance of the convening organization, institutional readiness for collaborative processes, the importance of stakeholder selection and process facilitation, the potentials of system representation as a basis for stakeholder dialogue and the importance of quantification versus evaluation of system representations. / (cont.) The basic implication of this research is that it would be myopic of engineering systems professionals to shift the burden of stakeholder involvement to decision-makers, and keep the analysis a merely expert-centered process. Due to the many subjective choices that have to be made with regards to system boundaries, choice of components, inclusion of linkages, nature of outputs and performance metrics and assumptions about data and relationships, system analysts are in fact not producing the analysis that will help the decision-making process. The best airport designs done with multi-tradeoff analysis and intricate options analysis may lead to nowhere if stakeholders affected by the project do not see their interests reflected in the analysis. The notion is that a good systems analysis is not one that impresses other engineering systems professionals with its complexity, but one that can actually address the problems at hand. / by Ali Mostashari. / Ph.D.

Symbiotic strategies in enterprise ecology : modeling commercial aviation as an Enterprise of Enterprises

Sgouridis, Sgouris P January 2007 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology, Management, and Policy Program, 2007. / Includes bibliographical references (p. 339-351). / We investigate the effectiveness of strategic alternatives that are designed to dampen the cyclicality manifest in the commercial aviation (CA)-related industries. In this research we introduce the conceptual framework of Enterprise of Enterprises (EoE) as an extension and special case of a System of Systems, to facilitate the design of strategic alternatives in an enterprise ecosystem characterized by loosely coupled enterprises. The constituent enterprises in an EoE exhibit managerial and operational independence and have diverse value functions that are often viewed by the enterprises as zero-sum games. We argue that this may not always be the case; for example, in the CA EoE both airline and airframe manufacturers constituents would benefit from a steadier influx of aircraft that counters the current situation that is characterized by relatively stable demand growth rate for air travel while airline profitability and aircraft ordering fluctuate intensely. A strategic alternative geared towards this EoE-wide desired state is "symbiotic". In order to identify such strategies, we use the EoE framework to analyze the CA-related industries and to specify their local value functions and the salient interfaces among them based on an extensive review of the literature on commercial aviation. We develop working hypotheses about the driving mechanisms of the cycle in the CA EoE informed by the literature on economywide and supply chain cyclicality. To test these hypotheses, we extend a system dynamics model of commercial aviation. After testing several individual strategic alternatives, we find that capacity management is key to cycle moderation. We then compare two diverse, non-collusive ways for capacity management: faster aircraft deliveries and semi-fixed production schedules generated by long-term forecasts. / (cont.) While both are promising, only the latter alternative is shown to be Pareto optimal. We also examine the potential synergistic effects from combining more than one strategic alternatives for which we also discuss implementation implications. The EoE framework and some of our findings can be applicable and generalizable to other industries facing intense cyclical behavior. / by Sgouris P. Sgouridis. / Ph.D.

Change management within an enterprise-wide packaged software implementation

Forrester, Ian D January 1996 (has links)
A research report submitted to the Faculty of Commerce University of the Witwatersrand, Johannesburg for the Degree of Masters of Commerce / Investments in information technology have in many cases failed to deliver the anticipated benefits. It is now accepted that real value can only be leveraged by linking IT implementation to organisational change and process redesign. The management of this change is inextricably linked to the overall success of the implementation. The focus of the research was on identifying what the key elements of successful change management were. Research into generic change management was used as a basis for determining these critical success factors. The applicability of these factors in the case of an enterprise wide package software implementation was then tested through a case study method. The research showed that the factors developed were applicable in managing technology driven change. In addition to the factors developed, additional factors were identified as being relevant in the case of packaged software implementations. / Andrew Chakane 2018

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