Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; and, (S.M.)--Massachusetts Institute of Technology. Operations Research Center, 2004. / Includes bibliographical references (p. 83-86). / 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, can be however very costly. The primary goal of this research is to propose planning models to re-route aircraft and re-time flight departures, either separately or simultaneously, in order to distribute slack time in the network optimally and reduce passenger delays. Using data from a major U.S. airline we observe that with our model, we can reduce flight and passenger delay levels. / by Sepehr Sarmadi. / S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; and, (S.M.)--Massachusetts Institute of Technology, Operations Research Center, 2005. / Includes bibliographical references (p. 89-91). / The purpose of this thesis is to estimate the impact of infrastructure-related add-on taxes and fees on the direct cost of air travel in the United States and the European Union. Its scope includes domestic travel in the United States and both domestic and intra-EU international travel within the European Union. For the United States, we work with over 4 million passenger records from the Department of Transportation 10% Ticket Samples to conclude that the effective tax rate (ETR) on the average base fare (BF) was 15.5% in the second quarter of 2002. The incidence is much heavier on the least expensive tickets because three out of the four add-on taxes and fees are based on the passenger's itinerary and are independent of the BF. Comparative analyses indicate that the ETR was 10.9% in 1993 and 16.1% in 2004, but a large portion of the ETR increase over the years is due to a significant decline in the yields achieved by the airlines. We also show that passengers traveling on low cost carriers are expected to face a higher ETR than those traveling on traditional network airliners or the "legacy carriers". Other analyses are performed to demonstrate that there was a statistically significant decrease in the number of segments per ticket from 2002 to 2004 and that the ETR would increase by 2.2% to 2.6% as a result of the new security fee policy proposed by the Bush Administration in 2005. Turning to the European side, our preliminary estimation shows that the average ETR was 12.5% in 2004 based on an analysis of over 300,000 ticket records provided by a Global Distribution System company. / (cont.) However, the ETR, in fact, varies greatly among the 15 European Union countries investigated, ranging from 6.6% to 24.4%, because of the complex and diverse taxation rules in place in Europe and because of the differences in average ticket prices. Finally, a simple analysis shows that the actual European ETR may be significantly higher than the ETR in the United States if the differences in charging schemes for the cost of air transportation infrastructure are taken into consideration. / by Shiro Yamanaka. / S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; and, (S.M.)--Massachusetts Institute of Technology, Operations Research Center, 2005. / Includes bibliographical references (p. 89-90). / Major package delivery companies employ hundreds of thousands of people, generate billions of dollars in revenues and operate very large fleets of ground vehicles ranging from custom- built package cars to large tractors and trailers. A crucial point for the profitability of these companies is, for a given level of service, to be able to run their operations at the lowest possible cost. In this thesis, we will contemplate the problem of the scheduling and routing on a regional and daily basis of the large tractor and trailer fleet of a large package delivery company. Our aim is to design a method for building the schedules associated with minimal operating costs. We consider deterministic situations in which all parameters are known exactly and we exclude possibilities of disruptions. Nonetheless even with these simplifications, the problem we consider is complex and large-scale, containing a very large number of constraints and parameters. Throughout this thesis, we examine different theoretical approaches including optimization models and algorithms. We implement some of these approaches in order to get practical results which can be implemented in practice. / by Raphaël Tardy. / S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; and, (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 1998. / Includes bibliographical references (leaves 94-103). / by Niranjan Krishnan. / S.M.

Thesis: S.M., Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2014. / Thesis: S.M. in Technology and Policy, Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2014. / This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. / "June 2014." Cataloged from student-submitted PDF version of thesis. / Includes bibliographical references (pages 139-141). / A feature of many conflicts is the presence of a border that separates an area of on-going military operations from an area that the enemy can use permissively. This thesis considers analytic techniques for planning military operations designed to interdict enemy forces crossing the border. Specifically, this thesis presents optimization-based methods for scheduling patrolling units and for positioning ground sensors in support of those patrolling units. These methods could serve as the framework for a tactical-level decision support tool designed to assist military planners assigned to border regions with resource allocation recommendations and trade-off comparisons. We propose tractable mixed integer optimization formulations for these solutions based on a network model of the routes in the region, operational constraints on the abilities of the patrolling units, and estimates of enemy force movements. Additionally, we develop robust extensions to these formulations that allow the model to account for a degree of enemy intelligence by incorporating the uncertain nature of the enemy movement estimates into the formulation. We evaluate the solutions to these formulations using simulations that account for different realizations of the uncertain enemy movement. This includes cases where the realized enemy movement closely matches the estimates made in the model and cases where the realizations are very different from the model. Additionally, we provide a modified greedy heuristic to the scheduling formulation that can serve as a tool for dynamically retasking a patrol to interdict enemy forces in real-time after a sensor detects enemy movement. Current planning for these operations are conducted by a staff with no decision making analytic tools. We approximate a version of this current planning method with an algorithm and show that our method outperforms it with both the deterministic and robust formulations. We compare the deterministic and robust formulations and demonstrate a process for choosing between the formulations, along with an explanation of the utility of the robust formulation. / by Jonathan L. Paynter. / S.M. / S.M. in Technology and Policy

Report (M. Eng.)--Virginia Polytechnic Institute and State University, 1994. / Abstract. Includes bibliographical references (leaves 54-55). Also available via the Internet.

Thesis (M.S.)--Boston University / The Earlab Project at Boston University Hearing Research Center (HRC), http://earlab.bu.edu, is a computational simulation system created by the HRC to allow researchers to run simulations efficiently, using software representations of physiological pathways. The existing complexity of Earlab presents difficulty for users who may wish to adjust the parameters necessary to change from models of the ear to models that simulate other physiological pathways. To address this difficulty, several approaches were explored to assist in formulating a new framework for editing files associated with Earlab. XML, a mark-up language, was used to derive a series of prototype XML based documents as replacements for existing Earlab files. Microsoft Visual Studio and C# was then used to create a prototype of a graphical user interface that is capable of displaying an XML based document in a visual manner. The resulting framework shows the process of the intake of an XML document of an sample Earlab model, the presentation of the model in a graphical framework and the ability to edit the model and receive feedback on the suitability of values in the model.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; and, (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, February 1999. / Includes bibliographical references (p. 83-86). / We consider the problem of integrating flight schedule design and fleet assignment decisions at airlines. The flight schedule design problem involves selecting and scheduling the set of flight legs that an airline will include in its service network. Fleet assignment involves assigning a particular aircraft type to each flight leg in the schedule. Due to the particularly challenging nature of schedule design problems, we limit our focus to that of incremental schedule design. Incremental schedule design involves the modification of a given flight schedule to produce an improved schedule by adding, deleting, and rescheduling flight legs. We present models and algorithms to achieve incremental schedule design and unlike previous schedule design efforts, we explicitly model flight demand and supply interactions. We present two case studies, using our models and algorithms. The first case study allows flight additions and deletions, while the second allows flights to be rescheduled. Future case studies well integrate these flight modification options. In our first case study, high-yield flights are maintained in the schedule and low-yield flights are dropped. Although the resulting schedule incurs higher spill costs, the savings from flight operating costs are sufficiently large to offset these higher spill costs, resulting in a more profitable schedule. The second case study, allowing flights to be rescheduled, considers several network sizes including the domestic network of a large U.S. airline. We consider Free Flight, a system allowing reduced flying times due to improved utilization of the national airspace. We find that reductions in flying times of about 10% can lead to dramatic cost savings for the airline, including reductions in the number of aircraft needed to fly the flight schedule. / by Manoj Lohatepanont. / S.M.

Thesis (S.M. in Technology and Policy)--Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program; and, (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2009. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 89-93). / Drivers in urban neighborhoods who cruise streets, seeking inexpensive on-street parking create a significant fraction of measured traffic congestion. The solution to this problem is to reduce the total traffic volume including cruising traffic by implementing a congestion pricing scheme: the imposition of a usage fee on a limited-capacity resource during times of high demand. We review the history of two alternatives for implementing the scheme: road pricing, which involves cordoning off a section of the center city and imposing a fee on all vehicles that enter it; and parking pricing, which increases the costs of on-street and perhaps off-street parking. We find that parking pricing is often a needed companion to road pricing, since in many environments a significant fraction of drivers are simply cruising, looking for inexpensive on-street parking. However, the effectiveness of parking pricing is difficult to analyze quantitatively because vehicles cruising for parking are not clearly distinguishable from other vehicles. We view that the pool of drivers cruising at any time can be modeled as a queue, where 'queue service' is the act of parking in a recently vacated parking space and queue discipline is SIRO - Service In Random Order. We develop a queueing model of such driver behavior, allowing impatient drivers to abandon the queue and to settle for expensive off-street parking. We then relate the model to the economic theory of congestion pricing, arguing that price differentials between on-street and off-street parking should be reduced in order to reduce traffic congestion. Using the "Parking Queue" model and collected data, we estimate that less than half of cruising drivers successfully find a vacant spot and the number of cruising vehicles is 10-20% of the total number of parking spaces during peak hours in the most congested area in Boston. / by Katsunobu Sasanuma. / S.M. / S.M.in Technology and Policy

The study has two objectives: to develop a methodology to identify success criteria for the VT CRC and to communicate outputs (success criteria) to selected members of the VT CRC’s stakeholders. A methodology is developed to identify success criteria based on the VT CRC's primary objectives. These primary objectives are: technology transfer and economic development. The purposes of a methodology are to place the VT CRC within the framework of Virginia Tech's larger missions and then to identify success criteria. A methodology consists of seven steps. There are thirteen success criteria which have been identified by a methodology. A methodology is based on management systems engineering theories, concepts, and tools/techniques. The study communicates outputs from a methodology by a questionnaire. Questionnaires will be sent to twelve selected members who are from the VT CRC, the university, tenants, and Town of Blacksburg. Their responses will be analyzed to decide whether these outputs are success criteria for the VT CRC and whether a methodology accomplishes its purposes. Furthermore, a background of Virginia Tech and a concept of university-related research parks will be discussed. Included in a discussion of Virginia Tech are missions, a modern view of a land-grant university, and roles of the Virginia Tech Foundation. Included in a discussion of research parks are purposes, benefits, and drawbacks. / Master of Science