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Queuing dynamics and control of departure operations at Boston Logan Airport

Idris, Husni Rifat
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 95 p.; 6488147 bytes; 6487906 bytes; application/pdf; application/pdf
ENG
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75.84%
by Husni Rifat Idris.; Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2001.; Includes bibliographical references (p. 91-95).

Robust airline schedule planning : review and development of optimization approaches

Agbokou, Claudine Biova, 1979-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 89 p.; 3114316 bytes; 3114123 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
65.88%
Major airlines aim to generate schedules that maximize profit potential and satisfy constraints involving flight schedule design, fleet assignment, aircraft maintenance routing and crew scheduling. Almost all aircraft and crew schedule optimization models assume that flights, aircraft, crews, and passengers operate as planned. Thus, airlines typically construct plans that maximize revenue or minimize cost based on the assumption that every flight departs and arrives as planned. Because flight delays and cancellations result from numerous causes, including severe weather conditions, unexpected aircraft and crew failures, and congestion at the airport and in the airspace, this deterministic, optimistic scenario rarely, if ever, occurs. In fact, schedule plans are frequently disrupted and airlines often incur significant costs in addition to those originally planned. To address this issue, an approach is to design schedules that are robust to schedule disruptions and attempt to minimize realized, and not planned, costs. In this research, we review recovery approaches and robustness criteria in the context of airline schedule planning. We suggest new approaches for designing fleet assignments that facilitate recovery operations, and we present models to generate plans that allow for more robust crew operations...

Coordinated dynamic planning for air and space operations; CDASOCS

Wroten, Matthew Christian
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 150 p.; 10073044 bytes; 10081238 bytes; application/pdf; application/pdf
ENG
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75.92%
Planners of military air and space operations in a battlefield environment seek to allocate resources against targets in a way that best achieves the objectives of the commander. In future conflicts, the presence of new types of assets, such as tactical space-based sensors and Operationally Responsive Spacelift (ORS) assets, will add complexity to air and space operations decisions. In order to best achieve objectives, planners of different types of assets will likely need to work collaboratively when formulating tasking for their resources. The purpose of this research is to investigate the challenges of air and space collaboration and to quantify its potential benefit. We model a future threat scenario involving a rogue nation with Weapons of Mass Destruction (WMD) capability and a significant air defense force. We consider three separately-controlled resource groups - aircraft, satellites, and ORS assets - to combat the target threat. In addition, we formulate a top-level coordination controller, whose job it is to effect collaborative decision-making among resource groups. Using a combination of pre-existing software and new algorithms, we develop the Coordinated Dynamic Air and Space Operations Control System (CDASOCS), which simulates controller-generated plans in a battlefield environment recurring over multiple planning periods. New algorithms are presented for both the top-level coordination controller and the ORS controller. The benefits of resource coordination in CDASOCS are demonstrated in three main experiments along with several parameter variation tests.; by Matthew Christian Wroten.; Thesis (S.M.)--Massachusetts Institute of Technology...

An Operations Research approach to aviation security

Martonosi, Susan Elizabeth
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 163 p.; 13913702 bytes; 13920567 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
85.85%
Since the terrorist attacks of September 11, 2001, aviation security policy has remained a focus of national attention. We develop mathematical models to address some prominent problems in aviation security. We explore first whether securing aviation deserves priority over other potential targets. We compare the historical risk of aviation terrorism to that posed by other forms of terrorism and conclude that the focus on aviation might be warranted. Secondly, we address the usefulness of passenger pre-screening systems to select potentially high-risk passengers for additional scrutiny. We model the probability that a terrorist boards an aircraft with weapons, incorporating deterrence effects and potential loopholes. We find that despite the emphasis on the pre-screening system, of greater importance is the effectiveness of the underlying screening process. Moreover, the existence of certain loopholes could occasionally decrease the overall chance of a successful terrorist attack. Next, we discuss whether proposed explosives detection policies for cargo, airmail and checked luggage carried on passenger aircraft are cost-effective.; (cont.) We define a threshold time such that if an attempted attack is likely to occur before this time...

Robust planning for Effects-Based Operations; Robust planning for EBO

Bryant, Corban Harrell
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 176 p.
ENG
Relevância na Pesquisa
75.89%
In this thesis. we introduce and analyze methods of creating theater-level robust mission plans for Effects Based Operations (EBO) of teams of Unmanned Aerial Vehicles (UAVs), and propose methods of effectively presenting the robust plan to an end user. Recent conflicts have demonstrated the utility of UAVs in performing Intelligence, Surveillance, and Reconnaissance (ISR) and strike missions. As UAVs become more common, high-level pre-planning and task delegation will increase in complexity, requiring computer aided planning. Traditional planning methods, based on deterministic input data, generate plans that become infeasible in uncertain environments. Because military operations tend to contain substantial amounts of uncertainty and re-planning at a theater level is costly, plans should be robust to uncertainty yet still accomplish desired effects. We present an effects-based planning framework in which we connect end effects to tasks, enabling planners to value task assignments based on their ability to achieve desired effects. We apply two robust planning techniques to this framework (Bertsimas/Sim and Chance Constrained Programming) and analyze their performance.; (cont.) We demonstrate how robust planning increases the length of time that a plan remains feasible in execution and achieves better overall value by avoiding re-planning costs. We analyze strengths and weaknesses of each model and suggest when their use is appropriate. Finally...

Dynamic planning under uncertainty for theater airlift operations

Martin, Kiel M. (Kiel Michael)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 93 p.
ENG
Relevância na Pesquisa
75.89%
In this thesis, we analyze intratheater airlift operations, and propose methods to improve the planning process. The United States Air Mobility Command is responsible for the air component of the world wide U.S. military logistics network. Due to the current conflict in Iraq, a small cell within Air Mobility Command, known as Theater Direct Delivery, is responsible for supporting ongoing operations by assisting with intratheater airlift. We develop a mathematical programming approach to schedule airlift missions that pick up and deliver prioritized cargo within time windows. In our approach, we employ composite variables to represent entire missions and associated decisions, with each decision variable including information pertaining to the mission routing and scheduling, and assigned aircraft and cargo. We compare our optimization-based approach to one using a greedy heuristic that is representative of the current planning process. Using measures of efficiency and effectiveness, we evaluate and compare the performance of these different approaches. Finally, we adjust selected parameters of our model and measure the resulting changes in operating performance of our solutions, and the required computational effort to generate the solutions.; by Kiel M. Martin.; Thesis (S.M.)--Massachusetts Institute of Technology...

Tropical cyclone preparedness and response : opportunities for operations research

Murphy, Maurice D
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 87 p.
ENG
Relevância na Pesquisa
85.9%
This thesis explores how operations research methods can be applied in the emergency response community by looking at two recent tropical storm disasters; tropical cyclone Yemyin in Pakistan, June 2007 and super typhoon Durian in the Philippines, Nov 2006. The case studies are used to highlight three common problem areas; determining the scope of the disaster, agency coordination, and relief logistics. The thesis identifies some operational models and applicable research and suggests that these ideas should be formulated as emergency management decision making tools particularly for use in the developing world.; by Maurice D. Murphy.; Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2008.; Includes bibliographical references (p. 79-87).

Data-driven approach to health care : applications using claims data

Bjarnadóttir, Margrét Vilborg
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 130 p.
ENG
Relevância na Pesquisa
65.86%
Large population health insurance claims databases together with operations research and data mining methods have the potential of significantly impacting health care management. In this thesis we research how claims data can be utilized in three important areas of health care and medicine and apply our methods to a real claims database containing information of over two million health plan members. First, we develop forecasting models for health care costs that outperform previous results. Secondly, through examples we demonstrate how large-scale databases and advanced clustering algorithms can lead to discovery of medical knowledge. Lastly, we build a mathematical framework for a real-time drug surveillance system, and demonstrate with real data that side effects can be discovered faster than with the current post-marketing surveillance system.; by Margrét Vilborg Bjarnadóttir.; Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2008.; Includes bibliographical references (p. 123-130).

Department of Operations Research

Eagle, James
Fonte: Monterey, California, Naval Postgraduate School Publicador: Monterey, California, Naval Postgraduate School
Tipo: Livro
EN_US
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Summary of activities and publications of the Department of Operations Research 2004/2005.

Summary of Research 1995, Department of Operations Research

Faculty of the Department of Operations Research, Naval Postgraduate School
Fonte: Office of the Associate Provost and Dean of Research, Naval Postgraduate School. Publicador: Office of the Associate Provost and Dean of Research, Naval Postgraduate School.
Tipo: Relatório
EN_US
Relevância na Pesquisa
95.88%
The views expressed in this report are those of the authors and do not reflect the official policy or position of the Department of Defense or the U.S. Government.; This report contains 40 summaries of research projects in the Department of Operations Research which were carried out under funding of the Naval Postgraduate School Research Program. A list of recent publications is also included which consists of conference presentations and publications, books, contributions to books, published journal papers, and technical reports.

Summary of Research 1996, Department of Operations Research

Faculty of the Department of Operations Research, Naval Postgraduate School
Fonte: Office of the Associate Provost and Dean of Research, Naval Postgraduate School. Publicador: Office of the Associate Provost and Dean of Research, Naval Postgraduate School.
Tipo: Relatório
EN_US
Relevância na Pesquisa
95.87%
The views expressed in this report are those of the authors and do not reflect the official policy or position of the Department of Defense or the U.S. Government.; This report contains summaries of research projects in the Department of Operations Research. A list of recent publications is also included which consists of conference presentations and publications, books, contributions to books, published journal papers, technical reports, and thesis abstracts.

Summary of Research 1998, Department of Operations Research

Faculty of the Department of Operations Research, Naval Postgraduate School
Fonte: Office of the Associate Provost and Dean of Research, Naval Postgraduate School. Publicador: Office of the Associate Provost and Dean of Research, Naval Postgraduate School.
Tipo: Relatório
EN_US
Relevância na Pesquisa
95.87%
The views expressed in this report are those of the authors and do not reflect the official policy or position of the Department of Defense or the U.S. Government.; This report contains summaries of research projects in the Department of Operations Research. A list of recent publications is also included which consists of conference presentations and publications, books, contributions to books, published journal papers, technical reports, and thesis abstracts.

Summary of Research 2000, Department of Operations Research

Faculty of the Department of Operations Research, Naval Postgraduate School
Fonte: Office of the Associate Provost and Dean of Research, Naval Postgraduate School. Publicador: Office of the Associate Provost and Dean of Research, Naval Postgraduate School.
Tipo: Relatório
EN_US
Relevância na Pesquisa
95.87%
The views expressed in this report are those of the authors and do not reflect the official policy or position of the Department of Defense or U.S. Government.; This report contains project summaries of the research projects in the Department of Operations Research. A list of recent publications is also included, which consists of conference presentations and publications, books, contributions to books, published journal papers, and technical reports. Thesis abstracts of students advised by faculty in the Department are also included.

Summary of Research 2001, Department of Operations Research

Faculty of the Department of Operations Research, Naval Postgraduate School
Fonte: Office of the Associate Provost and Dean of Research, Naval Postgraduate School. Publicador: Office of the Associate Provost and Dean of Research, Naval Postgraduate School.
Tipo: Relatório
EN_US
Relevância na Pesquisa
95.87%
The views expressed in this report are those of the authors and do not reflect the official policy or position of the Department of Defense or U.S. Government.; This report contains project summaries of the research projects in the Department of Operations Research. A list of recent publications is also included, which consists of conference presentations and publications, books, contributions to books, published journal papers, and technical reports. Thesis abstracts of students advised by faculty in the Department are also included.

Summary of Research 1997, Department of Operations Research

Faculty of the Department of Operations Research, Naval Postgraduate School
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Relatório
EN_US
Relevância na Pesquisa
85.87%
The views expressed in this report are those of the authors and do not reflect the official policy or position of the Department of Defense or the U.S. Government.; This report contains summaries of research projects in the Department of Operations Research. A list of recent publications is also included which consists of conference presentations and publications, books, contributions to books, published journal papers, technical reports, and thesis abstracts.

Supporting a Marine Corps Distributed Operations Platoon a quantitative analysis

Bain, Matthew D.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xxiv, 129 p. : col. ill., col. maps ;
Relevância na Pesquisa
65.91%
This research analyzes the critical logistical requirements of a U.S. Marine Distributed Operations Platoon with the goal of developing a sustainable support plan. The development of Distributed Operations (DO) is one of the Marine Corps' major transformational efforts. The concept is designed to make infantry units more lethal by leveraging training and technology to allow more dispersed and intelligence driven operations. Since a DO platoon will operate far from secure lines of communication and support bases, logistically supporting it will be challenging. Through the use of simulation, statistical analysis, and logistical modeling, this thesis identifies critical factors and capabilities that are important to the sustainment of a DO platoon operating from a Marine Expeditionary Unit (MEU). The research concludes with a feasible support concept combined with the means to assess the effect that supporting a DO platoon has on other MEU missions. Results indicate that quick response time and dedicated support assets from the supporting agency, typically augmented by MEU helicopters, are critical to the success of a DO platoon. This limits the flexibility of the MEU aviation element to support other MEU missions. The biggest payoff in improving logistical effectiveness is given by reducing the response time.

Exploration of force transitions in stability operations using multi-agent simulation

Vaughan, David P.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xxvi, 145 p. : ill. (some col.). ;
Relevância na Pesquisa
65.89%
Stability Operations have become the most prevalent mission for U.S. forces in the current global security environment. This research explores new methods to assist in determining when it is acceptable to downsize a force in a stability operation. The methodology developed provides insight into this problem by quantifying force protection risk, mission failure risk, and time in the context of the operational threat environment. The Pythagoras Multi-Agent Simulation and Data Farming techniques are used to investigate force-level comparison in a theoretical threat continuum based on a peacekeeping scenario similar to the Bosnian operation. The data from the simulation is to construct simple tools for decision makers. These tools are used collectively to find the balance, according to a commander's priorities, between the conflicting issues of force protection, mission success, and time. Two areas are identified as significant in achieving success in stability operations. They are troop posturing and troop employment. The problem is that they are often overlooked or under emphasized. The result of this research demonstrates that posturing and employment should be considered as factors equal to force size in contributing to the goal of maximizing force presence. In addition...

UAV mission planning under uncertainty; Unmanned Aerial Vehicles mission planning under uncertainty

Sakamoto, Philemon
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 209 p.
ENG
Relevância na Pesquisa
65.91%
With the continued development of high endurance Unmanned Aerial Vehicles (UAV) and Unmanned Combat Aerial Vehicles (UCAV) that are capable of performing autonomous fiunctions across the spectrum of military operations, one can envision a future military in which Air Component Commanders control forces comprised exclusively of unmanned vehicles. In order to properly manage and fully realize the capabilities of this UAV force, a control system must be in place that directs UAVs to targets and coordinates missions in a manner that provides an efficient allocation of resources. Additionally, a mission planner should account for the uncertainty inherent in the operations. Uncertainty, or stochasticity, manifests itself in most operations known to man. In the battlefield, such unknowns are especially real; the phenomenon is known as the fog of war. A good planner should develop plans that provide an efficient allocation of resources and take advantage of the system's true potential, while still providing ample "robustness" ill plans so that they are more likely executable and for a longer period of time.; (cont.) In this research, we develop a UAV Mission Planner that couples the scheduling of tasks with the assignment of these tasks to UAVs...

Minimizing airline passenger delay through integrated flight scheduling and aircraft routing

Sarmadi, Sepehr, 1977-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 89 p.; 3009465 bytes; 3009274 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
65.92%
Statistics show that airline flight delays and cancellations have increased continuously over the period from 1995 to 2000. During the same period, customer dissatisfaction and complaints have followed a similar, even more dramatic trend. In 2001, as a consequence of the September 1 th terrorist attacks and the resulting airline schedule reductions, delay levels decreased, but only temporarily. With growing passenger demands and stagnant capacity passenger delays and disruptions are again on the rise. Approaches to mitigate schedule disruptions include: 1) re-optimizing the schedule during operations after a disruption occurs. For example, an airline operations controller might decide to cancel or postpone some flight legs or to re-route some aircraft to recover the rest of the schedule; and 2) building robustness into the schedule in the planning stage. By robustness we mean the ability to absorb flight delays so these effects are minimized on passengers and crews. In many cases, trying to reduce delays in the planning stage can be less costly for the airlines, especially if the actions suggested to modify the schedule are not expensive. Pushing back a flight's departure time only ten minutes might cost the airline little but can potentially reduce the number of passenger misconnections given the stochastic nature of airline operations. Canceling a flight during operations for example...

Optimization-based allocation of force protection resources in an asymmetric environment

DeGregory, Keith W. (Keith William)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 139 p.
ENG
Relevância na Pesquisa
65.87%
More than four years after the end of major combat operations in the 2003 Iraq War, the United States military continues to sustain casualties at rates higher than those during the ground campaign. Combat service support soldiers conducting daily convoy operations on the Iraqi road network account for a large number of these casualties. One reason for this is the threat's affinity to targeting soft, vulnerable, high-payoff targets through the use of roadside bombs, otherwise known as improvised explosive devices. This enemy tactic is characteristic of asymmetric warfare, in which a lesser opponent opposes a force far superior in numbers, equipment, and technology. In an asymmetric operating environment, threats blend in with the local populace making them hard to detect and are easily capable of multi-directional attacks; absent are the linear battlefields of past wars where logistical soldiers operated in the relative safety of the rear battlefield. This thesis explores a mathematical approach to decide how to use available resources to best protect logistical convoys. To achieve this we first model the threat using probabilistic models and identify input data requirements associated with the operating environment and other relevant factors.; (cont.) Second...