Página 23 dos resultados de 2122 itens digitais encontrados em 0.036 segundos

‣ Short-term precipitation nowcasting for composite radar rainfall fields

Van Horne, Matthew P. (Matthew Philip), 1980-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 115 p.; 1424532 bytes; 11107239 bytes; application/pdf; application/pdf
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Precipitation nowcasting at very short lead times is a difficult and important earth science goal. The implications of nowcasting extend into aviation, flood forecasting and other areas. Using correlation analysis for the generation of velocity vectors to advect a composite radar rainfall field is the method of nowcasting utilized in this work. The MIT Lincoln Laboratory Growth and Decay Storm Tracker (GDST) is a correlation-based nowcasting algorithm that utilizes spatial filtering to eliminate the potentially adverse effects of transient, small-scale rainfall features in the correlation step. The GDST is used in this work to evaluate the benefits of image filtering as compared to a situation where the filtering is absent. The GDST generates a spatially variable velocity field for input rainfall field advection. Forecasts made using this enhancement are compared to forecasts made using a single velocity value for all input pixels in order to determine the benefits of allowing for differential motion within the storm envelope. The results from three storm cases show that image filtering provides improvement in forecast accuracy over an unfiltered case however, to fully determine any benefits from using spatially variable velocities requires more work. This work also documents the development and testing of a new correlation-based nowcasting algorithm. The Automated Precipitation Extrapolator (APEX) builds on advancements made over the past 40 years to provide highly accurate precipitation nowcasts. Initial testing shows that APEX-generated forecasts are more accurate than persistence forecasts...

‣ On triangular finite elements for general shell structures

Lee, Phill-Seung, 1971-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 162 leaves; 7818925 bytes; 7839613 bytes; application/pdf; application/pdf
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In general, triangular elements are most efficient to discretize arbitrary shell geometries. However, in shell finite element analysis, usually quadrilateral elements are used due to their better performance. Indeed, there does not exist yet a "uniformly optimal" triangular shell element. The work in this thesis focuses on the development of continuum mechanics based triangular shell elements (of low and high order) which overcome the known disadvantages and show uniform optimal convergence. As the shell thickness decreases, the behavior of shell structures falls into one of three categories (bending dominated, membrane dominated or mixed problems) depending on the shell geometry and the boundary conditions. We develop a numerical scheme to evaluate the behavior of shells and perform the asymptotic analysis of three shell structures. We also present the asymptotic analysis results of a highly sensitive shell problem which has a fluctuating load-scaling factor. These results provide basic information for effective numerical tests of shell finite elements. We develop a new systematic procedure for the strain interpolation of MITC triangular shell finite elements that results into spatially isotropic elements. We propose possible strain interpolations and develop five new specific triangular shell finite elements. Considering the asymptotic behavior of shells...

‣ Numerical models of phosphate esters in the Chattahoochee River

Haffey, Samuel Fraad, 1973-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 135 leaves; 4983716 bytes; 4983524 bytes; application/pdf; application/pdf
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A numerical model was constructed to assess the magnitude of organophosphoric acid triester sinks in the Chattahoochee River and to identify concentration patterns downstream of point source discharges. The model was built using WASP5 and supporting software packages. The model simulated mass transport of tri-butyl phosphate, tri (2-butoxyethyl) phosphate, and tri (2-chloroethyl) phosphate within a reach of the river bounded by Buford Dam and Northern Atlanta. Several potential mechanisms for the removal of the phosphate esters from the water column were considered. These were biodegradation, sorption to settling solids, volatilization, and oxidation by free radicals. Of the three phosphate esters considered by the model, tri (2-chloroethyl) phosphate was predicted to be the most resistant to degradation by natural attenuation processes. Tri (2- butoxyethyl) phosphate showed the most potential for degradation in surface waters. Biodegradation and sorption to settling solids were predicted to be the most effective processes for the removal of tri (2-butoxyethyl) phosphate. Concentration patterns at several locations downstream of point source discharges were predicted for the three compounds. Concentration patterns were found to be affected by the diurnal flow variation caused by the operation of two hydroelectric dams within the modeled reach.; by Samuel Fraad Haffey.; Thesis (M. Eng.)--Massachusetts Institute of Technology...

‣ Determining the removal effectiveness of flame retardants from drinking water treatment processes

Lin, Joseph C. (Joseph Chris), 1981-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 105, [7] p.; 3901639 bytes; 3901448 bytes; application/pdf; application/pdf
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Low concentrations of xenobiotic chemicals have recently become a concern in the surface water environment. The concern expands to drinking water treatment processes, and whether or not they remove these chemicals while going through the treatment plant. In this study, the concentrations of organophosphoric acid triester flame retardants tributyl phosphate, tri(2-chloroethyl) phosphate, and ethanol, 2-butoxy-, phosphate (3:1) were measured after major treatment processes at the Chattahoochee Drinking Water Plant in Atlanta, Georgia, USA. The findings indicated significant removal of all three organophosphate triesters after the pre-treatment chemical addition of sodium hypochlorite. The interaction of sodium hypochlorite and organophosphate triesters, through oxidation, was suspected to be the reason for the removal. Second, the concentrations of tri(2-chloroethyl) phosphate after the filtration stage and at the clearwell were much greater than values after the sedimentation stage, and were well above the concentration measured at the intake. Exposure to the chemicals within the treatment plant was the chief potential reason for the heightened concentrations.; by Joseph C. Lin.; Thesis (M. Eng.)--Massachusetts Institute of Technology...

‣ The use of nondestructive testing methods for the condition assessment of concrete bridge girders

Unruh, Richard Cornelius, 1974-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 72 p.; 2459585 bytes; 2459393 bytes; application/pdf; application/pdf
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There are over 594,000 publicly controlled bridges in the United States. Concrete and pre-stressed concrete bridges account for nearly 50% of the bridges in the US inventory. This proportion is increasing each year, as new bridges tend to be constructed of concrete. This trend makes it vital for engineers to be able to accurately assess the condition of concrete for maintenance and repair decisions. The use of nondestructive testing methods can help reduce the backlog of deficient bridges in two ways. First, these techniques will allow inspectors to get a more accurate view of the condition of a bridge. The second way by which NDT can help is by allowing inspectors to locate damage earlier. This thesis is an attempt to capture the most current ideas for a very specific application of NDT: determining the condition of reinforced concrete bridges overall and bridge girders, in particular. To this end, attention is given to why NDT is needed and what aspects of concrete condition can be addressed with NDT. Some NDT methodologies that are, or may soon be, promising for concrete applications are discussed. Case studies are presented to demonstrate how NDT can be applied to concrete bridge girders and proposals are made for future areas of study and development.; by Richard Cornelius Unruh...

‣ Effect of deep excavation on an adjacent pile foundation

Iliadelis, Dimitrios
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 77 leaves; 14738845 bytes; 14738455 bytes; application/pdf; application/pdf
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The thesis studies the behavior of single axially loaded pile located close to a 30m deep braced excavation in Marine Clay corresponding to site conditions of the Kallang formation in Singapore. Parametric analyses were carried out, using non linear three-dimensional finite element methods (with Plaxis Foundation 3-D), comparing different pile lengths (17m, 30m and 42m) cross sections (solid concrete sections of 0.4m and 1.Om diameter) and proximity to the excavation (2m-10m). The results focus on the development of horizontal deformations and bending moments due to the excavation process. The computed results for end-bearing piles (42m long) are compared with semi-empirical design methods proposed by Poulos and Chen (1997). In general, this design method substantially underestimates the computed wall deflections and bending moments. This result confirms the importance of site-specific analyses for these types of complex soil-structure interactions.; by Dimitrios Iliadelis.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2006.; Includes bibliographical references (leaf 70).

‣ Multi-sensor rainfall data assimilation using ensemble approaches

Chatdarong, Virat, 1978-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 203 p.; 40225181 bytes; 40224473 bytes; application/pdf; application/pdf
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Rainfall is a major process transferring water mass and energy from the atmosphere to the surface. Rainfall data is needed over large scales for improved understanding of the Earth climate system. Although there are many instruments for measuring rainfall, none of them can provide continuous global coverage at fine spatial and temporal resolutions. This thesis proposes an efficient methodology for obtaining a probabilistic characterization of rainfall over an extended time period and spatial domain. The characterization takes the form of an ensemble of rainfall replicates, each conditioned on multiple measurement sources. The conditional replicates are obtained from ensemble data assimilation algorithms (Kalman filters and smoothers) based on a recursive cluster rainfall model. Satellite measurements of cloud-top temperatures are used to identify areas where rainfall can possibly occur. A variational field alignment algorithm is used to estimate rainfall advective velocity field from successive cloud-top temperature images. A stable pseudo-inverse improves the stability of the algorithms when the ensemble size is small. The ensemble data assimilation is implemented over the United States Great Plains during the summer of 2004.; (cont.) It combines surface rain-gauge data with three satellite-based instruments. The ensemble output is then validated with ground-based radar precipitation product. The recursive rainfall model is simple...

‣ Regional seismic risk of railway system including derailment consequences

Uchiyama, Yayoi Misu
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 114 leaves
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To evaluate the seismic risk of railway networks, a derailment consequence model and a regional approach are developed The consequence model estimates the casualty and fatality rates for passengers as a function of train speed and includes two sub-models. The first sub-model, which is for the case when the train remains in its own track after derailment, was developed using historical accident data. The casualty and fatality rates are estimated using a linear logistic model. The other sub-model, for the case of head-on collision and train fall, was developed using numerical simulation results by the U.S.DOT. The regional approach estimates earthquake risk for the entire network In the approach, first, the probabilities of possible derailment scenarios including head-on collision cases are calculated To calculate the probabilities of derailment due to seismic vibration and facility damage, the derailment probability model is applied After one scenario is selected by Monte Carlo method based on calculated probabilities, the consequences are calculated for the scenario applying the consequence model developed previously. Through an application to the Tohoku Shinkansen line, we illustrate how the system is in many ways an improvement over the current JR East system.; by Yayoi Misu Uchiyama.; Thesis (S.M.)--Massachusetts Institute of Technology...

‣ Online learning algorithm for structural control using magnetorheological actuators

Laflamme, Simon, M. Eng. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 88 p.
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Magnetorheological actuators are promising devices for mitigating vibrations because they only require a fraction of energy for a similar performance to active control. Conversely, these semi-active devices have limited maximum forces and are hard to model due to the rheological properties of their fluid. When considering structural control, classical theories necessitate full knowledge of the structural dynamic states and properties most of which can only be estimated when considering large-scale control, which may be difficult or inaccurate for complicated geometries due to the non-linear behaviour of structures. Additionally, most of these theories do not take into account the response delay of the actuators which may result in structural instabilities. To address the problem, learning algorithms using offline learning have been proposed in order to have the structure learn its behaviour, but they can be perceived as unrealistic because earthquake data can hardly be produced to train these schemes. Here, an algorithm using online learning feedback is proposed to address this problem where the structure observes, compares and adapts its performance at each time step, analogous to a child learning his or her motor functions.; (cont.) The algorithm uses a machine learning technique...

‣ Identification of factors responsible for successes or failures in the supply chain based on real-world case studies

Simotas, Georgios
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 106 leaves
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The decision of firms from industrialized nations to outsource part or all of their supply chain activities to offshore countries, like in China, carries with it two major issues. The first is related to the costs and benefits of outsourcing and the second to risks and problems that may arise in-between the supply chain participants. A supply chain vulnerability analysis is currently performed under the "Speed to Market" project. The ultimate output of the project will be a software model capable of improving the ability of companies to ship intermediate or finished products to and from China. The purpose of my research is to identify the factors that are mostly responsible for the strength or volatility of the supply chain of a firm and come to conclusions about the questions that a firm has to answer before taking the decision to outsource. Such questions usually arise throughout the supply chain and are related to suppliers, inventories, demand forecasting and intellectual property issues.; by Georgios Simotas.; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2007.; Includes bibliographical references (leaves 97-101).

‣ Optimization of stiffener placement for thin plate buckling

Hopkins, Thomas Andrew
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 67 leaves
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Stiffened plates are a common component in many structures, from plate girders and box girder bridges to ships and offshore structures. Plates and stiffened plates buckle into doubly curved surfaces, substantially complicating the mathematics for an analytic solution. Finite element methods allow direct analysis of stiffened plates without requiring the solving of complicated differential equations. This analysis considers stiffened plates from the buoy of a tension leg platform designed to support a 5 megawatt wind turbine. The interior plates were stiffened using conventional, large, triangular, diamond and truss type stiffener arrangements. The truss scheme was designed or "tuned" specifically to the suppress the first buckling mode of the particular plate, and compared to other more arbitrary forms of material placement. The results showed that the truss stiffener that was tuned to the first mode was the most effective in increasing the critical buckling load. The truss arrangement increased the critical load by 7, 269 kips compared to 4, 180 for conventional, 2, 912 for large, 911 for triangular and 2,562 kips for a diamond stiffener arrangement.; by Thomas Andrew Hopkins.; Thesis (M. Eng.)--Massachusetts Institute of Technology...

‣ Normalized mechanical properties of resedimented Gulf of Mexico clay from Integrated Ocean Drilling Program Expedition Leg 308

Mazzei, David P. C. (David Peter Clark)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 137 leaves
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During Integrated Ocean Drilling Program (IODP) Expedition Leg 308, many Whole Core Samples were recovered from the Ursa Basin in the Gulf of Mexico. Post-cruise geotechnical testing found these samples to be highly disturbed due to the sampling process. This research will determine mechanical properties of laboratory Resedimented samples created using recovered Leg 308 sediment. A seven triaxial compression tests, Ko consolidated, were performed to ascertain these mechanical properties as a function of consolidation stress. Consolidation stress for these specimen ranges from 150 kPa up to 1,200 kPa. Axial strain induced on the soil during laboratory consolidation was approximately 60%. Results show that with an increase in Ko values there is a decrease in undrained shear strength, which is in accord with research completed on resedimented Boston Blue clay (RBBC) at MIT and also intact material that was recovered from this expedition. Undrained shear strength of the material is between 0.24 and 0.27, which is weaker than what is expected, according to SHANSEP. Friction angle of the material ranges from approximately 220 to 260. There is not any apparent relationship between Ko and modulus, friction angle or consolidation stress. Reaching end of primary proved to be a difficult task...

‣ Estimation of economic impact of freight distribution due to highway closure

Hu, Shiyin
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 68 leaves
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The main aim of this study is to provide a theoretical framework and methodology to estimate and analyze the economic impact of freight disruption due to highway closure. The costs in this study will be classified into three groups: private operating costs for carriers, logistics and scheduling costs, and indirect costs for the market. The resource saving method is used to measure private operating costs for carriers. The stated preference method and the logit model are used to measure logistics and scheduling costs. The input-output analysis is used to measure indirect costs for carriers. The recommended methodology can be used to the estimate economic impact of freight disruption due to highway closure. The framework can be used as a stepping stone for future research.; by Shiyin Hu.; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2008.; Includes bibliographical references (leaves 64-68).

‣ Examining changes in transit passenger travel behavior through a Smart Card activity analysis

Mojica, Carlos H
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 141 p.
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Transit passenger behavior is an area of major interest for public transportation agencies. The relationship between ridership and maintenance projects, however, is unexplored but increasingly relevant in the era of aging infrastructure. This thesis bridges this gap by analyzing changes in Smart Card activity for a sample of rail commuters during a large scale maintenance project in Chicago. Results show that between 8% and 11% of the passengers used the bus system as a commuting alternative while the majority of them continued using the train under deteriorated service conditions. Comparisons to a control zone show that between 2% and 7% of the commuters did not use transit for their trips. Using the observed results, we model the shift from rail to bus using a binary logit model. Implications of the findings are discussed.; by Carlos H. Mojica.; Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning; and, (S.M. in Transportation)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2008.; Includes bibliographical references (p. 139-140).

‣ An empirical study of the coordination in a distributed software development team

Xie, Xusong, 1975-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 92 p.; 4166884 bytes; 4177387 bytes; application/pdf; application/pdf
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As today's software systems become more and more complicated, coordinating the development of such systems has been an important factor to their successful implementation. The need for good coordination is especially important when the development team is geographically distributed and has to rely on information and communication technologies to support its activities. With limited available coordination mechanisms, distributed software teams need to carry out a set of coordination functions effectively throughout the software development process. In addition, in response to the changes in context and task, distributed software teams needed to be adaptive in their coordination. In this study, I try to understand how different coordination methods and tools could serve the changing coordination needs in software development through an empirical study of a distributed software team's practice.; by Xusong Xie.; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.; Includes bibliographical references (p. 89-92).

‣ Headcut retreat resulting from plunge pool erosion in a 3D landscape evolution model

Flores Cervantes, Javier Homero, 1977-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 143 p.; 5543701 bytes; 5543500 bytes; application/pdf; application/pdf
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Headcut retreat produced by plunge pools is represented using existing concepts about this type of erosion. The model estimates retreat rates, given flow, height of the headcut, upstream slope and Manning's roughness, and the relevant soil parameters (erodibility and critical shear stress). The model was analyzed to study its behavior as its input parameters changed, and its output was compared to experimental observations. Next, the plunge pool mechanism was implemented in an existing 3D landscape evolution model (CHILD) that includes other mechanisms of erosion like fluvial erosion and diffusion. The effects of headcut retreat on the landscape and of the landscape on the headcut retreat mechanism were investigated to learn what factors promote gully erosion and the extent of the impact of this type of erosion on the landscape. The results indicate that headcut retreat is most significant in zones comprising either gentle slopes or large headcut heights. Additional hydraulic conditions promoting to headcut retreat due to plunge pool erosion were found.; by Javier Homero Flores Cervantes.; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.; Includes bibliographical references (p. 139-143).

‣ The effect of development on nitrogen loading on St. John, U.S. Virgin Islands

Navato, Alfred Patrick
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 110 p.
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The majority of St. John's land and coast is a National Park and is protected by the federal government. In spite of these restrictions, the population of St. John has risen in the past fifteen years as has the number of tourists that visit the island. A possible side-effect to the growing population is increased nitrogen loading to the bays, which can impact the benthic habitat. The purpose of this thesis is to evaluate the extent of the effects of human developments on nitrogen loading of the bays on St. John, U. S. Virgin Islands. This is accomplished by taking nitrogen samples of the bays, using ArcGIS and the Nitrogen Loading Model to estimate the nitrogen loading of the bays, and correlating historical nitrogen concentrations with increases in population. While the analysis of nitrogen samples of the bays is inconclusive, the Nitrogen Loading Model estimates that bays with greater levels of development have higher amounts of nitrogen loading. Historical nitrogen concentrations show little relationship between the level of development of the watersheds and the concentration of nitrogen within the bays. Overall, there is little evidence that nitrogen loading from development is causing excessive nitrogen loading.; by Alfred Patrick Navato.; Thesis (M. Eng.)--Massachusetts Institute of Technology...

‣ The iLab service broker : a software infrastructure providing common services in support of Internet accessible laboratories

Yehia, Karim Y., 1980-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 91 p.; 3826084 bytes; 3825886 bytes; application/pdf; application/pdf
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Remote laboratories that are accessible via the Internet are becoming a common phenomenon in higher education institutions. This thesis describes the iLab Service Broker architecture, a software infrastructure that supports these Internet-accessible labs by providing a number of services that facilitates their administration and management. These common services are authentication, authorization, lab administration, scheduling and data storage. While Internet- accessible laboratories may be quite varied in terms of the technologies they use, they tend to have similar topologies, consisting of a lab client, lab server and database. The end-user interacts with the lab client to issue commands to, and view results from the lab server, and the database stores data from the lab server. The Service Broker's internal architecture constitutes the business logic rules that govern how the common services are administered. Its external architecture exposes these services, using web services, and makes them available to the remote laboratories in a platform-independent manner. The Service Broker attempts to cater for the different experiment models that Internet-accessible labs host. These models are the batched experiment, the interactive experiment and the sensor lab experiment.; by Karim Y. Yehia.; Thesis (S.M.)--Massachusetts Institute of Technology...

‣ The potential for low-cost airlines in Asia

Dietlin, Philipp, 1979-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 139 p.; 8163645 bytes; 8181867 bytes; application/pdf; application/pdf
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The purpose of this thesis is to assess the potential for low-cost airlines in Asia. Low-cost airlines have been very successful in North America and Europe and have significantly impacted the airline industry and its stakeholders. In what ways and to what extent this might be repeatable in Asia is the underlying question of this thesis. An investigation of the low-cost airline business model reveals that there are a number of key elements that make it so successful on both sides of the Atlantic. But what works in North America and Europe may not be feasible in Asia. An analysis of the Asian airline industry shows that it differs from the rest of the world in several important dimensions, which will substantially affect prospective low-cost airlines. On the one hand, the rigid regulatory frameworks in most parts of Asia and the fact that many traditional Asian airlines have some of the world's lowest unit costs may not allow Asian low-cost airlines to thrive in the same way as they have in other parts of the world. On the other hand, a breakdown of Asia's socioeconomic indicators shows that the continent is bound to experience significant growth in intra-Asia air travel over the coming years. The low-cost airline business in Asia is therefore challenging in several ways but potentially very lucrative. The possible impacts that an increasing presence of low-cost airlines in Asia would have on the various stakeholders in the region are substantial. While some of these stakeholders will likely benefit from a growing presence of low-cost airlines in Asia...

‣ Anticipatory behavior in lane changing models

Rao, Anita (Anita Anant)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 120 p.; 5794922 bytes; 5799914 bytes; application/pdf; application/pdf
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Actions performed by drivers in case of lane changing behavior are usually the result of some plan the driver has in mind. This involves anticipating future scenarios and persisting in order to execute the plan. The objective of this thesis is to develop a framework for modeling the lane-changing behavior that captures the anticipatory behavior of drivers. Two ways of capturing this behavior - a dynamic programming model and an explicit forced merging model - are developed in this thesis. The fact that drivers constantly modify their plans in the light of new information, suggests the use of a dynamic programming approach, where the solution takes the form of an optimal decision rule that specifies drivers' optimal decisions as a function of their current information. A theoretical framework is developed and the advantages and disadvantages of the approach are discussed. The computational complexity of applying such a model suggests adopting an alternative approach to the problem. The explicit forced merging model captures the planning and persistent behavior of drivers. The model is essentially a gap acceptance model that explicitly captures normal and forced merging behavior of vehicles merging from the on-ramp to the freeway.; (cont.) Aggressive drivers that tend to initiate forced merging persist in their plan to complete the merging process. The parameters of the model are estimated using detailed trajectory data. Estimation results show that the lane changing behavior is affected by relative speeds of the neighboring vehicles with respect to the merging vehicle...