14 research outputs found

    Modeling Economic Impacts of the Inland Waterway Transportation System

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    The inland waterway transportation system of the United States (U.S.) handles 11.7 billion tons of freight annually and connects the heartland of the U.S. with the rest of the world by providing a fuel-efficient and environmentally friendly mode of transportation. This dissertation aims to create decision support tools for maritime stakeholders to measure the economic impacts of the inland waterway transportation systems under real world scenarios including disruptions, demand changes, port expansion decisions, and channel deepening investments. Monte Carlo simulation, system dynamics, discrete-event simulation, agent-based modeling, and multiregional input-output modeling techniques are utilized to analyze the complex relationships between inland waterway transportation system components and regional economic impact factors. The first research contribution illustrates that the expected duration of a disruption determines whether decision makers are better off waiting for the waterway system to reopen or switching to an alternative mode of transportation. Moreover, total disruption cost can be reduced by increasing estimation accuracy of disruption duration. The second research contribution shows that without future investment in inland waterway infrastructure, a sustainable system and associate economic impacts cannot be generated in the long-term. The third research contribution illustrates that investing in bottleneck system components results in higher economic impact than investing in non-bottleneck components. The developed models can be adapted to any inland waterway transportation system in the U.S. by utilizing data obtained by publically available sources to measure the economic impacts under various scenarios to inform capital investment decisions and support an economically sustainable inland waterway transportation system

    Antônio Sérgio Coelho

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    Historia, evolución y perspectivas de futuro en la utilización de técnicas de simulación en la gestión portuaria: aplicaciones en el análisis de operaciones, estrategia y planificación portuaria

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    Programa Oficial de Doutoramento en Análise Económica e Estratexia Empresarial. 5033V0[Resumen] Las técnicas de simulación, tal y como hoy las conocemos, comenzaron a mediados del siglo XX; primero con la aparición del primer computador y el desarrollo del método Monte Carlo, y más tarde con el desarrollo del primer simulador de propósito específico conocido como GPS y desarrollado por Geoffrey Gordon en IBM y la publicación del primer texto completo dedicado a esta materia y llamado the Art of Simulation (K.D. Tocher, 1963). Estás técnicas han evolucionado de una manera extraordinaria y hoy en día están plenamente implementadas en diversos campos de actividad. Las instalaciones portuarias no han escapado de esta tendencia, especialmente las dedicadas al tráfico de contenedores. Efectivamente, las características intrínsecas de este sector económico, le hacen un candidato idóneo para la implementación de modelos de simulación con propósitos y alcances muy diversos. No existe, sin embargo y hasta lo que conocemos, un trabajo científico que compile y analice pormenorizadamente tanto la historia como la evolución de simulación en ambientes portuarios, ayudando a clasificar los mismos y determinar cómo estos pueden ayudar en el análisis económico de estas instalaciones y en la formulación de las oportunas estrategias empresariales. Este es el objetivo último de la presente tesis doctoral.[Resumo] As técnicas de simulación, tal e como hoxe as coñecemos, comezaron a mediados do século XX; primeiro coa aparición do computador e o desenvolvemento do método Monte Carlo e máis tarde co desenvolvemento do primeiro simulador de propósito específico coñecido como GPS e desenvolvido por Geoffrey Gordon en IBM e a publicación do primeiro texto completo dedicado a este tema chamado “A Arte da Simulación” (K.D. Tocher, 1963). Estas técnicas evolucionaron dun xeito extraordinario e hoxe en día están plenamente implementadas en diversos campos de actividade. As instalacións portuarias non escaparon desta tendencia, especialmente as dedicadas ao tráfico de contenedores. Efectivamente, as características intrínsecas deste sector económico, fanlle un candidato idóneo para a implementación de modelos de simulación con propósitos e alcances moi variados. Con todo, e ata o que coñecemos, non existe un traballo científico que compila e analiza de forma detallada tanto a historia como a evolución da simulación en estes ambientes portuarios, clasificando os mesmos e determinando como estes poden axudar na análise económica destas instalacións e na formulación das oportunas estratexias empresariais. Este é o último obxectivo da presente tese doutoral.[Abstract] Simulation, to the extend that we understand it nowadays, began in the middle of the 20th century; first with the appearance of the computer and the development of the Monte Carlo method, and later with the development of the first specific purpose simulator known as GPS developed by Geoffrey Gordon in IBM. This author published the first full text devoted to this subject “The Art of Simulation” in 1963. These techniques have evolved in an extraordinary way and nowadays they are fully implemented in different fields of activity. Port facilities have not escaped this trend, especially those dedicated to container traffic. Indeed, the intrinsic characteristics of this economic sector, make it a suitable candidate for the implementation of simulation with very different purposes and scope. However, to the best of our knowelegde, there is not a scientific work that compiles and analyzes in detail both, the history and the evolution of simulation in port environments, contributing to classify them and determine how they can help in the economic analysis of these facilities and in the formulation of different business strategies. This is the ultimate goal of this doctoral thesis

    Research Week 2015

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    Aeronautics and Space Report of the President

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    Nineteen eighty-eight marked the United States' return to space flight with two successful space shuttle launches in September and December, as well as six successful expendable rocket launches. Meanwhile, many other less spectacular but important contributions were made in aeronautics and space by the 14 participating government organizations. Each organization's aeronautics and/or space activities for the year are presented. The organizations involved include: (1) NASA; (2) Department of Defense; (3) Department of Commerce; (4) Department of Energy; (5) Department of the Interior; (6) Department of Agriculture; (7) Federal Communications Commission; (8) Department of Transportation; (9) Environmental Protection Agency; (10) National Science Foundation; (11) Smithsonian Institution; (12) Department of State; (13) Arms Control and Disarmament Agency; and (14) United States Information Agency

    Aeronautics and space report of the president, 1974 activities

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    The U.S. Government activities for 1974 in aeronautics and space are presented. Significant contributions toward the fulfillment of the nation's goals in space and aeronautics are covered, including application of space systems and technology to beneficial uses on earth, exploration of space and increase of scientific knowledge, development of improved space systems and technology, international cooperation, and advancement of civil and military aeronautics. Also in 1974, space activities in the private sector expanded to provide additional services to the public. The accomplishments are summarized

    Exploration of alternative frameworks for transportation infrastructure strategy development

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    Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2010.Cataloged from PDF version of thesis.Includes bibliographical references.This thesis introduces the notion of a strategy development framework for transportation infrastructure systems. A strategy development framework has several dimensions: the organizations that own.infrastructure, the ownership structure employed, the type and quantity of revenues generated, the revenue allocation methods for re-investing in the infrastructure, the degree of integration across transportation modes and other sectors, and the geographic scales controlled. We analyze the behavior of a range of alternative frameworks through a combined quantitative-qualitative approach, using Portugal's highway transportation system as the context. Drawing on strategy literature from the management field, we begin by defining and characterizing a range of alternative strategy development frameworks for transportation infrastructure systems. Next, we analyze these frameworks quantitatively using an agent-based model which simulates the evolution of Portugal's intercity highway network over time and space. By varying the frameworks' dimensions (e.g., type of revenue, revenue allocation method, geographic scale of control), we observe differences in the resulting investment decisions for the network. We evaluate the performance of these investment decisions according to a range of metrics in order to determine which frameworks lead to desirable outcomes. The simulation, however, cannot fully capture the relationship between a framework and investment outcomes for the highway system, so we complement the model with a qualitative analysis which combines empirical cases and predicted stakeholder dynamics. The integrated quantitative-qualitative evaluation allows us to explain a wider range of trade-offs associated with each alternative framework. The contributions of this research are threefold: (1) we offer the notion of strategy development, which allows for recognition and inclusion of emergent outcomes, as an alternative to the narrower concept of transportation planning; (2) we determine the influence of advanced transportation technologies (typically studied for their operational benefits) on strategy development; and (3) we explore the consequences of fundamental changes to the strategy development framework, notably along the dimension of geographic scale. While our theory and methods are applied to the case of Portugal's highway system-and we strive to produce results of value to that nation-we believe they can be profitably applied in other transportation contexts as well.by Travis P. Dunn.Ph.D

    Management: A bibliography for NASA managers

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    This bibliography lists 731 reports, articles and other documents introduced into the NASA Scientific and Technical Information System in 1990. Items are selected and grouped according to their usefulness to the manager as manager. Citations are grouped into ten subject categories: human factors and personnel issues; management theory and techniques; industrial management and manufacturing; robotics and expert systems; computers and information management; research and development; economics, costs and markets; logistics and operations management; reliability and quality control; and legality, legislation, and policy

    ENVIROSAT-2000 report: Federal agency satellite requirements

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    The requirement of Federal agencies, other than NOAA, for the data and services of civil operational environmental satellites (both polar orbiting and geostationary) are summarized. Agency plans for taking advantage of proposed future Earth sensing space systems, domestic and foreign, are cited also. Current data uses and future requirements are addressed as identified by each agency
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