69 research outputs found
Air Force Institute of Technology Research Report 2013
This report summarizes the research activities of the Air Force Institute of Technology’s Graduate School of Engineering and Management. It describes research interests and faculty expertise; lists student theses/dissertations; identifies research sponsors and contributions; and outlines the procedures for contacting the school. Included in the report are: faculty publications, conference presentations, consultations, and funded research projects. Research was conducted in the areas of Aeronautical and Astronautical Engineering, Electrical Engineering and Electro-Optics, Computer Engineering and Computer Science, Systems Engineering and Management, Operational Sciences, Mathematics, Statistics and Engineering Physics
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
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
An Information-Theoretic Framework for Consistency Maintenance in Distributed Interactive Applications
Distributed Interactive Applications (DIAs) enable geographically dispersed users
to interact with each other in a virtual environment. A key factor to the success
of a DIA is the maintenance of a consistent view of the shared virtual world for
all the participants. However, maintaining consistent states in DIAs is difficult
under real networks. State changes communicated by messages over such networks
suffer latency leading to inconsistency across the application. Predictive Contract
Mechanisms (PCMs) combat this problem through reducing the number of messages
transmitted in return for perceptually tolerable inconsistency. This thesis examines
the operation of PCMs using concepts and methods derived from information theory.
This information theory perspective results in a novel information model of PCMs
that quantifies and analyzes the efficiency of such methods in communicating the
reduced state information, and a new adaptive multiple-model-based framework for
improving consistency in DIAs.
The first part of this thesis introduces information measurements of user behavior
in DIAs and formalizes the information model for PCM operation. In presenting the
information model, the statistical dependence in the entity state, which makes using
extrapolation models to predict future user behavior possible, is evaluated. The
efficiency of a PCM to exploit such predictability to reduce the amount of network
resources required to maintain consistency is also investigated. It is demonstrated
that from the information theory perspective, PCMs can be interpreted as a form
of information reduction and compression.
The second part of this thesis proposes an Information-Based Dynamic Extrapolation
Model for dynamically selecting between extrapolation algorithms based on
information evaluation and inferred network conditions. This model adapts PCM
configurations to both user behavior and network conditions, and makes the most
information-efficient use of the available network resources. In doing so, it improves
PCM performance and consistency in DIAs
Nuclear Power
The world of the twenty first century is an energy consuming society. Due to increasing population and living standards, each year the world requires more energy and new efficient systems for delivering it. Furthermore, the new systems must be inherently safe and environmentally benign. These realities of today's world are among the reasons that lead to serious interest in deploying nuclear power as a sustainable energy source. Today's nuclear reactors are safe and highly efficient energy systems that offer electricity and a multitude of co-generation energy products ranging from potable water to heat for industrial applications. The goal of the book is to show the current state-of-the-art in the covered technical areas as well as to demonstrate how general engineering principles and methods can be applied to nuclear power systems
Forest Management and Water Resources in the Anthropocene
Decades of research has provided a depth of understanding on the relationships among forests and water, and how these relationships change in response to climate variability, disturbance, and forest management. This understanding has facilitated a strong predictive capacity and the development of best management practices to protect water resources with active management. Despite this understanding, the rapid pace of changes in climate, disturbance regimes, invasive species, human population growth, and land use expected in the 21st century is likely to create substantial challenges for watershed management that may require new approaches, models, and best management practices. These challenges are likely to be complex and large scale, involving a combination of direct effects and indirect biophysical watershed responses, as well as socioeconomic impacts and feedbacks. We explore the complex relationships between forests and water in a rapidly changing environment, examine the trade-offs and conflicts between water and other resources, and examine new management approaches for sustaining water resources in the future
Advances in Evolutionary Algorithms
With the recent trends towards massive data sets and significant computational power, combined with evolutionary algorithmic advances evolutionary computation is becoming much more relevant to practice. Aim of the book is to present recent improvements, innovative ideas and concepts in a part of a huge EA field
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