Dissertations / Theses on the topic 'Flight Delay'

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1

Yuan, Duojia, and S3024047@student rmit edu au. "Flight Delay-Cost Simulation Analysis and Airline Schedule Optimization." RMIT University. Aerospace, Mechanical, Manufacturing Engineering, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080618.092923.

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In order to meet the fast-growing demand, airlines have applied much more compact air-fleet operation schedules which directly lead to airport congestion. One result is the flight delay, which appears more frequently and seriously; the flight delay can also significantly damage airline's profitability and reputation The aim of this project is to enhance the dispatch reliability of Australian X Airline's fleet through a newly developed approach to reliability modeling, which employs computer-aided numerical simulation of the departure delay distribution and related cost to achieve the flight schedule optimization. The reliability modeling approach developed in this project is based on the probability distributions and Monte Carlo Simulation (MCS) techniques. Initial (type I) delay and propagated (type II) delay are adopted as the criterion for data classification and analysis. The randomicity of type I delay occurrence and the internal relationship between type II delay and changed flight schedule are considered as the core factors in this new approach of reliability modeling, which compared to the conventional assessment methodologies, is proved to be more accurate on the departure delay and cost evaluation modeling. The Flight Delay and Cost Simulation Program (FDCSP) has been developed (Visual Basic 6.0) to perform the complicated numerical calculations through significant amount of pseudo-samples. FDCSP is also designed to provide convenience for varied applications in dispatch reliability modeling. The end-users can be airlines, airports and aviation authorities, etc. As a result, through this project, a 16.87% reduction in departure delay is estimated to be achieved by Australian X Airline. The air-fleet dispatch reliability has been enhanced to a higher level - 78.94% compared to initial 65.25%. Thus, 13.35% of system cost can be saved. At last, this project also achieves to set a more practical guideline for air-fleet database and management upon overall dispatch reliability optimization.
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2

Bai, Yuqiong. "ANALYSIS OF AIRCRAFT ARRIVAL DELAY AND AIRPORT ON-TIME PERFORMANCE." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2573.

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In this research, statistical models of airport delay and single flight arrival delay were developed. The models use the Airline On-Time Performance Data from the Federal Aviation Administration (FAA) and the Surface Airways Weather Data from the National Climatic Data Center (NCDC). Multivariate regression, ANOVA, neural networks and logistic regression were used to detect the pattern of airport delay, aircraft arrival delay and schedule performance. These models are then integrated in the form of a system for aircraft delay analysis and airport delay assessment. The assessment of an airport¡¯s schedule performance is discussed. The results of the research show that the daily average arrival delay at Orlando International Airport (MCO) is highly related to the departure delay at other airports. The daily average arrival delay can also be used to evaluate the delay performance at MCO. The daily average arrival delay at MCO is found to show seasonal and weekly patterns, which is related to the schedule performance. The precipitation and wind speed are also found contributors to the arrival delay. The capacity of the airport is not found to be significant. This may indicate that the capacity constraint is not an important problem at MCO. This research also investigated the delays at the flight level, including the flights with delay ¡Ý0 minute and the flights with delay ¡Ý15min, which provide the delay pattern of single arrival flights. The characteristics of single flight and their effect on flight delay are considered. The precipitation, flight distance, season, weekday, arrival time and the time spacing between two successive arriving flights are found to contribute to the arrival delay. We measure the time interval of two consecutive flights spacing and analyze its effect on the flight delay and find that for a positively delayed flight, as the time space increases, the probability of the flights being delayed will decrease. While it was possible to calculate the immediate impact of originating delays, it is not possible to calculate their impact on the cumulative delay. If a late departing aircraft has no empty space in its down line schedule, it will continue to be late. If that aircraft enters a connecting airport, it can pass its lateness on to another aircraft. In the research we also consider purifying only the arrival delay at MCO, excluding the flights with originating delay >0. The model makes it possible to identify the pattern of the aircraft arrival delay. The weather conditions are found to be the most significant factors that influence the arrival delay due to the destination airport.
M.S.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering
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3

Matsutani, Megumi. "Robust adaptive flight control systems in the presence of time delay." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/79339.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2013.
This electronic version was submitted and approved by the author's academic department as part of an electronic thesis pilot project. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from department-submitted PDF version of thesis.
Includes bibliographical references (p. 161-165).
Adaptive control technology is a promising candidate to deliver high performance in aircraft systems in the presence of uncertainties. Currently, there is a lack of robustness guarantees against time delay with the difficulty arising from the fact that the underlying problem is nonlinear and time varying. Existing results for this problem have been quite limited, with most results either being local or at best, semi-global. In this thesis, robust adaptive control for a class of plants with global boundedness in the presence of time-delay is established. This class of plants pertains to linear systems whose states are accessible. The global boundedness is accomplished using a standard adaptive control law with a projection algorithm for a range of non-zero delays. The upper bound of such delays, i.e. the delay margin, is explicitly computed. The results of this thesis provide a highly desirable fundamental property of adaptive control, robustness to time-delays, a necessary step towards developing theoretically verifiable flight control systems.
by Megumi Matsutani.
Ph.D.
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4

Sarmadi, Sepehr 1977. "Minimizing airline passenger delay through integrated flight scheduling and aircraft routing." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/29401.

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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.
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5

Nilsson, Andreas. "Analysis of robustness and delay propagation in Scandinavian Airlines swedish flight traffic program." Thesis, KTH, Matematik (Inst.), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99174.

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6

Sun, He S. M. Massachusetts Institute of Technology. "An integrated model of flight and passenger delay for policy analysis in the National Air Transportation System." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104329.

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Thesis: S.M. in Transportation, Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2016.
Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (page 99).
Demand for air travel has increased over the years and so have airport delays and congestion. Delays have a huge impact on airline costs and influence the satisfaction of passengers, thus becoming an important topic of research in the field of air transportation. In recent literature, a Passenger Delay Calculator (PDC) was proposed to estimate passenger delays. The PDC computes passenger delays for a specified day based on actual flight schedules, fight cancellation information, and ticket booking information. However, since actual fight schedules are a necessary input, the PDC cannot be applied directly to hypothetical scenarios, in which different cancellation strategies are implemented and their impact on passenger delays are evaluated. A different model. Airport Network Delays (AND), has also been developed recently. The AND model estimates fight delays and relies on an input in which demand consists of the national planned fight schedule for any given day. In this thesis, we have attempted to incorporate these two models, the AND and the PDC, within a single framework, so that the resulting new integrated model can compute passenger delays without requiring an actual flight-schedule input. The integrated model would certainly increase the usefulness and applicability of the PDC since it could be used with hypothetical scenarios, different flight cancellation strategies, etc. We first describe the framework of the integrated model for studying flight delays and passenger delays at a daily scale. The integrated model includes four components: a Tail Recovery Model, Flight Cancellation Algorithms, a Refined Airport Network Delay (RAND) model, and the PDC. The Tail Recovery Model recovers missing tail numbers for many flights recorded in the Aviation System Performance Metrics (ASPM) database. The Flight Cancellation Algorithms implement alternative strategies for flight cancellations in the presence of large delays, such as cancelling flights with long flight delays or flights with a large ratio of flight delay divided by the seating capacity of the aircraft. The RAND model is an extension of the AND, in which two implicit assumptions of the AND model have been modified. The RAND model produces better estimates of flight delays in the sense of replicating actual flight delays obtained from the ASPM database. The overall integrated model is able to compute passenger delays and relies only on planned flight schedules rather than actual flight schedules. Moreover, the integrated model facilitates the study of factors that influence flight delays, such as weather conditions and demand fluctuations, and evaluates the impact of different cancellation strategies on passenger delays. Using actual data from different days, we conclude that passenger delays can be reduced on the busiest traffic days through improved flight cancellation strategies. In the second part of the thesis, we extend the RAND model to compute flight delays on a monthly scale using different capacity profiles as input. These capacity profiles can be directly obtained from Federal Aviation Administration (FAA) reports or constructed by using classical machine learning algorithms on airport-level data. We validate our estimation of flight delays by using data of January, 2008, showing that both the capacity profiles and the RAND perform well in terms of replicating the actual monthly flight delays. These results imply that an effort can be made to develop an integrated model incorporating the RAND, the PDC etc. at a monthly scale or even at any generic time scale.
by He Sun.
S.M. in Transportation
S.M.
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7

Bly, Elizabeth 1981. "Effects of reduced IFR arrival-arrival wake vortex separation minima and improved runaway operations sequencing on flight delay." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/28908.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2005.
Includes bibliographical references (p. 99-101).
(cont.) 65.6% and 67.0% and the average NAS delay by 24.3% and 24.7% relative to the FIFO and Serve-the-Longest-Queue algorithms respectively.
Two methods to improve runway throughput are evaluated in this thesis. The first, increasing runway capacity during periods of bad weather by reducing IFR arrival-arrival wake vortex separations. The second, increasing runway efficiency in all weather conditions using event sequencing algorithms. Two algorithms were studied: a Serve-the-Longest-Queue algorithm for flight sequencing coupled with a greedy heuristic algorithm for runway assignment and a mixed integer programming optimization algorithm for simultaneous flight sequencing and runway assignment. The MIT Extensible Air Network Simulation (MEANS) was used to simulate NAS op- erations to determine the potential benefits in terms of delay reduction for both methods. For the case where reduced IFR arrival-arrival wake vortex separations was studied, the Airport Runway Capacity Calculator (ARCC), developed in support of this work, was used to determine the increased capacity at eleven congested US airports. Results indicate that the total delay in the National Airspace System (NAS) could have been reduced by 31.8% over the month of January, 1999 (a reduction of 243,672 minutes) representing a benefit of 116 minutes per IFR hour. For the cases where the event sequencing algorithms were studied, the algorithms were only implemented at Newark Airport (EWR) and the resulting delay values were compared to the performance of a FIFO algorithm that is representative of existing operations. The flight delay for the Serve-the-Longest-Queue algorithm and the FIFO algorithm were similar, though relative performance depended on the airline schedule. The integer programming optimization algorithm out performed the other two algorithms significantly reducing the average delay at EWR by
by Elizabeth Bly.
S.M.
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8

Fabbiane, Nicolò. "Transition delay in boundary-layer flows via reactive control." Doctoral thesis, KTH, Stabilitet, Transition, Kontroll, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-187173.

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Transition delay in boundary-layer flows is achieved via reactive control of flow instabilities, i.e. Tollmien-Schlichting (TS) waves. Adaptive and model-based control techniques are investigated by means of direct numerical simulations (DNS) and experiments. The action of actuators localised in the wall region is prescribed based on localised measurement of the disturbance field; in particular, plasma actuators and surface hot-wire sensors are considered. Performances and limitations of this control approach are evaluated both for two-dimensional (2D) and three-dimensional (3D) disturbance scenarios. The focus is on the robustness properties of the investigated control techniques; it is highlighted that static model-based control, such as the linear-quadratic- Gaussian (LQG) regulator, is very sensitive to model-inaccuracies. The reason for this behaviour is found in the feed-forward nature of the adopted sensor/actuator scheme; hence, a second, downstream sensor is introduced and actively used to recover robustness via an adaptive filtered-x least-mean-squares (fxLMS) algorithm. Furthermore, the model of the flow required by the control algorithm is reduced to a time delay. This technique, called delayed-x least-mean-squares (dxLMS) algorithm, allows taking a step towards a self-tuning controller; by introducing a third sensor it is possible to compute on-line the suitable time-delay model with no previous knowledge of the controlled system. This self-tuning approach is successfully tested by in-flight experiments on a motor-glider. Lastly, the transition delay capabilities of the investigated control con- figuration are confirmed in a complex disturbance environment. The flow is perturbed with random localised disturbances inside the boundary layer and the laminar-to-turbulence transition is delayed via a multi-input-multi-output (MIMO) version of the fxLMS algorithm. A positive theoretical net-energy- saving is observed for disturbance amplitudes up to 2% of the free-stream velocity at the actuation location, reaching values around 1000 times the input power for the lower disturbance amplitudes that have been investigated.
I den här avhandlingen har reglertekniska metoder tillämpats för att försena omslaget från ett laminärt till ett turbulent gränsskikt genom att dämpa tillväxten av små instabiliteter, så kallade Tollmien-Schlichting vågor. Adaptiva och modellbaserade metoder för reglering av strömning har undersökts med hjälp av numeriska beräkningar av Navier-Stokes ekvationer, vindtunnelexperiment och även genom direkt tillämpning på flygplan. Plasmaaktuatorer och varmtrådsgivare vidhäftade på ytan av plattan eller vingen har använts i experimenten och modellerats i beräkningarna. Prestanda och begränsningar av den valda kontrollstrategin har utvärderats för både tvådimensionella och tredimensionella gränsskiktsinstabiliteter. Fokus har varit på metodernas robusthet, där vi visar att statiska metoder som linjär-kvadratiska regulatorer (LQG) är mycket känsliga för avvikelser från den nominella modellen. Detta beror främst på att regulatorer agerar i förkompenseringsläge (”feed-foward”) på grund av strömningens karaktär och placeringen av givare och aktuatorer. För att minska känsligheten mot avvikelser och därmed öka robustheten har en givare införts nedströms och en adaptiv fXLMS algoritm (filtered-x least-mean-squares) har tillämpats.                  Vidare har modelleringen av fXLMS-algoritmen förenklats genom att ersätta överföringsfunktionen mellan aktuatorer och givare med en lämplig tidsfördröjning.  Denna  metod som kallas för dxLMS (delayed-x least-mean-squares) kräver att ytterligare en givare införs långt uppströms för att kunna uppskatta hastigheten på de propagerande instabilitetsvågorna. Denna teknik har tillämpats framgångsrikt för reglering av gränsskiktet på vingen av ett segelflygplan. Slutligen har de reglertekniska metoderna testas för komplexa slumpmässiga tredimensionella störningar som genererats uppströms lokalt i gränsskiktet. Vi visar att en signifikant försening av laminärt-turbulentomslag äger rum med hjälp av en fXLMS algoritm. En analys av energibudgeten visar att för ideala aktuatorer och givare kan den sparade energiåtgången på grund av minskad väggfriktion vara upp till 1000 gånger större än den energi som använts för reglering.
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Mollén, Katarina. "Water Depth Estimation Using Ultrasound Pulses for Handheld Diving Equipment." Thesis, Linköpings universitet, Institutionen för systemteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-117061.

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This thesis studies the design and implementation of an ultra-sonic water depth sounder. The depth sounder is implemented in a hand-held smart console used by divers. Since the idea of echo sounding is to measure the flight time between transmitting the signal and receiving the echo, the main challenge of this task is to find a time-of-flight (ToF) estimation for a signal in noise. It should be suitable for this specific application and robust when implemented in the device. The thesis contains an investigation of suitable ToF methods. More detailed evaluations of the matched filter, also known as the correlation method, and the linear phase approach are done. Aspects like pulse frequency and duration, speed of sound in water and underwater noise are taken into account. The ToF-methods are evaluated through simulation and experiments. The matched filter approach is found suitable based on these simulations and tests with signals recorded by the console. This verification leads to the implementation of the algorithm on the device. The algorithm is tested in real time, the results are evaluated and improvements suggested.
Denna rapport behandlar skattning av vattendjup med hjälp av ultraljudspulser och implementation av detta. Djupmätaren implementeras i en handhållen dykarkonsoll. Eftersom grundidén i ekolodning är att mäta tiden mellan att pulsen skickas iväg och att ekot tas emot är en stor del av utmaningen att hitta en lämplig metod för att skatta flykttiden för en signal i brus. Metoden ska passa för detta användingsområde och vara robust. Rapporten tar upp tidigare forskning gjord inom flykttidsestimering. De metoder som utvärderas för implementation är det matchade filtret, också kallad korrelationsmetoden, och linjär fas-metoden. Andra aspekter som avvägs och utreds är pulsfrekvens och pulsvaraktighet, ljudets hastighet och brus under vattnet. Metoderna för att skatta flykttid utvärderas genom simuleringar. Det matchade filtret bedöms vara lämpligt baserat på dessa simuleringar och experiment med data inspelad med konsollen. Denna verifikation leder till att algoritmen implementeras på konsollen. Den implementerade algoritmen testas i realtid, resultaten utvärderas och förbättringar föreslås.
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Knotková, Martina. "Ochrana spotřebitele v letecké dopravě." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-7684.

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The thesis is focused on dynamically developing field of the air transportation. It is based on rights and duties of airlines and consumers. It is mapping the most important current law moves of Czech Republic which has been changed and agreed for a consumer protection. It describes consumer rights in the case of a flight delay and cancellation, refusal of entry on the plane and in the case of baggage problems. It also touches the issues of advertised price of plane tickets. It is followed by the analysis of current situation of the observance of consumer rights and their point of view on some controversial topics.
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11

Smith, R. Marshall. "A method for determining and reducing transport delays in the flight simulation environment." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10242009-020229/.

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12

Vandehzad, Mashhood. "Efficient flight schedules with utilizing Machine Learning prediction algorithms." Thesis, Malmö universitet, Fakulteten för teknik och samhälle (TS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-20663.

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While data is becoming more and more pervasive and ubiquitous in today’s life, businesses in modern societies prefer to take advantage of using data, in particular Big Data, in their decision-making and analytical processes to increase their product efficiency. Software applications which are being utilized in the airline industry are one of the most complex and sophisticated ones for which conducting of data analyzing techniques can make many decision making processes easier and faster. Flight delays are one of the most important areas under investigation in this area because they cause a lot of overhead costs to the airline companies on one hand and airports on the other hand. The aim of this study project is to utilize different machine learning algorithms on real world data to be able to predict flight delays for all causes like weather, passenger delays, maintenance, airport congestion etc in order to create more efficient flight schedules. We will use python as the programming language to create an artifact for our prediction purposes. We will analyse different algorithms from the accuracy perspective and propose a combined method in order to optimize our prediction results.
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Kostyleva, Daria [Verfasser]. "Experimental Studies of Proton-Unbound Nuclei via In-Flight Decay Spectroscopy / Daria Kostyleva." Gieߟen : Universitätsbibliothek, 2021. http://d-nb.info/1228828970/34.

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Massri, Karim. "Kaon identification and search for lepton number violation in K± decay-in-flight experiments at CERN." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5451/.

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A search for the Lepton Number Violating decay \(K\)\(^±\) → \(π\)\(^∓\)\(μ\)\(^±\)\(μ\)\(^±\) has been performed using the data collected by the NA48/2 experiment in 2003 and 2004. The signal event selection, the background rejection, the evaluation of the muon identification efficiency and the statistical methods used for the data interpretation are presented. Based on 1.8 x 10\(^1\)\(^1\) kaon decays in the fiducial volume and using several models for the signal, upper limits for the branching ratio \(B\)(\(K\)\(^±\) → \(π\)\(^∓\)\(μ\)\(^±\)\(μ\)\(^±\)) of the order of 10\(^-\)\(^1\)\(^0\) have been obtained for 90%, 95% and 99% confidence levels, improving the previous best limit of one order of magnitude. The Cherenkov differential counter used for kaon identification in the NA62 experiment, equipped with approximately 30% of the photo-detectors, was installed and tested during a Technical Run in 2012. The counter's ability of distinguishing between kaons and pions has been validated via pressure scan procedure. The data collected have been used for evaluating the kaon efficiency and time resolution. The extrapolation to the full-sized detector has been also estimated.
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Závodník, Ondřej. "Aspekty vyhodnocení vzdušného prostoru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228077.

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Diplomová práce se zabývá jednak popisem stavu letecké dopravy a to zejména co se týče její bezpečnosti, plynulosti, propustnosti a kapacity. Výše uvedené je poté zhodnoceno v části věnující se aspektům nebezpečnosti vzdušného prostoru v jednotlivých fázích letu.
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Majuwana, Gamage Chaminda. "Instrumentation and Kinetic Studies of Surface-Induced Dissociation in a Time-of-Flight Mass Spectrometer." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/193928.

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The surface-induced dissociation (SID) method is introduced into a Bruker matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI TOF MS) as an efficient ion fragmentation method. Ion trajectory calculations using the SIMION 7.0 ion optics program are performed and results are combined with simple unimolecular decay calculations in order to study the kinetics of the SID processes. In this instrument, the observation time frame for SID fragments lies in the submicrosecond region, allowing the specific detection of submicrosecond fragmentation channels. MALDI-produced protonated peptides in the mass range of 700 - 1500 Da and radical ions produced by laser irradiation of fullerenes C60 and C70 are fragmented at a gold surface coated with a self-assembled monolayer of alkanethiol to obtain TOF SID TOF mass spectra. For the SID of peptides in the hyperthermal energy regime, a fragmentation time frame of tens to a few hundreds of nanoseconds was calculated for the observed fast fragmentation channels (Chapters 3 and 4). Theoretical and experimental peak shape comparisons assuming unimolecular decay kinetics indicated a log rate constant in the range 6 - 7 (Chapter 4). Energy and mass resolved kinetic studies are also carried out. The contribution of special structural features to peptide fragmentation and the possibility of different fragmentation mechanisms such as sequential and parallel pathways are investigated. The results indicate a unimolecular decay process for observed fast peptide fragments ruling out a surface-shattering mechanism. Fullerene ions, especially C60+., showed a fragmentation behavior producing C2n+. fragments with an even number of C units at collision energies in the range of 100 - 400 eV (Chapter 5). At around 400 eV, additional small fragments appeared that are apart by only a single C unit. According to the calculated fragmentation times and the theoretical and experimental peak shape comparisons assuming unimolecular decay kinetics, both these processes may be approximated by parallel fast unimolecular decay processes with fragmentation time frames of tens to hundreds of nanoseconds although the poor theoretical and experimental peak shape matching for example in the decay of C60+. to C19+. may suggest deviations from a one-step unimolecular decay process.
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Eng, Tony Liang. "De novo peptide sequencing from matrix-assisted laser desorption/ionization-time of flight post-source-decay spectra." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86584.

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Reed, Alan Thomas. "Decay studies of neutron-rich nuclei." Thesis, University of Liverpool, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367175.

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Xu, Xiaodong [Verfasser]. "Observation and investigation of the new proton-unbound nuclei 30Ar and 29Cl with in-flight decay spectroscopy / Xiaodong Xu." Gießen : Universitätsbibliothek, 2016. http://d-nb.info/1117438015/34.

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20

Vaaben, Bo, and Jesper Larsen. "Mitigation of airspace congestion impact on airline networks." Elsevier, 2015. https://publish.fid-move.qucosa.de/id/qucosa%3A72734.

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In recent years European airspace has become increasingly congested and airlines can now observe that en-route capacity constraints are the fastest growing source of flight delays. In 2010 this source of delay accounted for 19% of all flight delays in Europe and has been increasing with an average yearly rate of 17% from 2005 to 2010. This paper suggests and evaluates an approach to how disruption management can be combined with flight planning in order to create more proactive handling of the kind of disruptions, which are caused by congested airspace. The approach is evaluated using data from a medium size European carrier and estimates a lower bound saving of several million USD.
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Fricke, Tim [Verfasser], Florian [Akademischer Betreuer] [Gutachter] Holzapfel, and Klaus [Gutachter] Bengler. "Flight Control with Large Time Delays and Reduced Sensory Feedback / Tim Fricke ; Gutachter: Klaus Bengler, Florian Holzapfel ; Betreuer: Florian Holzapfel." München : Universitätsbibliothek der TU München, 2017. http://d-nb.info/1134865821/34.

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Tomic, David. "Service Aware Traffic Distribution in Heterogeneous A2G Networks." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-248995.

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Airplanes have different ways to connect to the ground, including satellite air-to-ground communication (SA2GC) and direct air-to-ground communication (DA2GC). Each connection/link offers a different varying amount of transmission capacity over flight time. The traffic generated in the airplane must be forwarded/sent to ground over the available links. It is however not clear how the traffic should be forwarded so that traffic quality of service (QoS) requirements are met. The thesis at hand considers this question, and implements an algorithm handling the forwarding decision with three different forwarding schemes. Those consider traffic parameters in calculating a value assigned to each traffic flow, over a combination of priority, delay requirement and the number of times a traffic flow is dropped. The forwarding algorithm relies on proposed in-flight broadband connectivity (IFBC) network traffic and air-to-ground (A2G) link models, which aim at approximating the network environment of future IFBC networks. It is shown that QoS requirements of traffic flows in terms of packet loss and delay cannot be satisfied with capacities offered by current DA2GC and SA2GC technology. For a future scenario, with higher assumed link capacities, the QoS requirements are met to a higher extent. This is shown in lower packet loss and delay experienced by the respective traffic flows. Further, it is shown that the performance can be improved with specific forwarding schemes used by the forwarding algorithm. It is also investigated how a web cache can be used as a fallback technology. For this a required web cache hit rate is found, which should be high enough to offload the network with content served from the cache. Overall, the thesis aims at proposing an efficient traffic forwarding technique, and at giving insight into an alternative if this technique fails.
Flygplan har olika sätt att ansluta till marken, inklusive satellit-mark-kommunikation (SA2GC) och direkt luft till markkommunikation (DA2GC). Varje anslutning/länk erbjuder en annan varierande mängd överföringskapacitet under flygtid. Den trafik som genereras i flygplanet måste vidarebefordras/skickas till marken över de tillgängliga länkarna. Det är emellertid inte klart hur trafiken ska vidarebefordras så att trafiksäkerhetskvaliteten (QoS) uppfylls. Avhandlingen handlar om denna fråga och implementerar en algoritm som hanterar vidarebefordringsbeslutet med tre olika vidarebefordringssystem. De betraktar trafikparametrar vid beräkning av ett värde som tilldelas varje trafikflöde, över en kombination av prioritet, fördröjningskrav och antalet gånger ett trafikflöde tappas. Vidarebefordringsalgoritmen är beroende av föreslagna bredbandsförbindelser (IFBC) i nätverk och A2G-länkmodeller, som syftar till att approximera nätverksmiljön för framtida IFBC-nätverk. Det visas att QoS-krav på trafikflöden när det gäller paketförlust och fördröjning inte kan tillgodoses med kapacitet som erbjuds av nuvarande DA2GC- och SA2GC-teknik. För ett framtida scenario, med högre antagna länkkapacitet, uppfylls QoS-kraven i högre utsträckning. Detta visas med lägre paketförlust och fördröjning som upplevs av respektive trafikflöden. Vidare är det visat att prestanda kan förbättras med specifika vidarekopplingsscheman som används av vidarebefordringsalgoritmen. Det undersöks också hur en webbcache kan användas som en återgångsteknik. För detta hittas en obligatorisk webbcache-träfffrekvens, som bör vara tillräckligt hög för att ladda upp nätverket med innehåll som serveras från cacheminnet. Sammanfattningsvis syftar uppsatsen till att föreslå en effektiv trafiköverföringsteknik och att ge insikt om ett alternativ om denna teknik misslyckas.
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23

Valldor-Blücher, Johan. "Upgrading the Control and Monitoring system for the TOFOR neutron time-of-flight spectrometer at JET." Thesis, Uppsala universitet, Institutionen för fysik och astronomi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-197586.

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This report describes the development and testing of the upgraded Control and Monitoring (C&Mu) system for the TOFOR neutron spectrometer. TOFOR is currently performing plasma diagnostics for the JET experimental fusion reactor. The purpose of the C&Mu system is to enable monitoring of the amplitude dependent time delays of TOFOR. In order to perform this monitoring function the C&Mu system must comprise a pulsed light source with variable intensity and a reference time signal. In this work a reference time signal has been retrieved from a laser comprising a motorized polarizer. This has been accomplished by installing a photomultiplier tube and a beamsplitter cube. The beamsplitter cube splits the laser light into two parts and directs one part into the photomultiplier tube. The photomultiplier tube converts the light into an electrical reference time signal. A control program has been developed for the motorized polarizer, enabling the user to vary the intensity of the light over the interval from 0% to 100%. The C&Mu system has been performance tested and it was found that the time resolution of the system is about 0.1ns and the time stability of the system is about 0.12ns over 27 hours. The system is more than adequate to monitor variations in time delays at TOFOR of several nanoseconds, over a full JET day. The C&Mu system is ready to be installed on TOFOR.
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24

Tucci, Henrricco Nieves Pujol. "Aplicação do seis sigma no processo de abastecimento de combustível de aeronaves – um estudo de múltiplos casos." Universidade Nove de Julho, 2016. http://bibliotecatede.uninove.br/handle/tede/1569.

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Submitted by Nadir Basilio (nadirsb@uninove.br) on 2017-02-22T21:06:29Z No. of bitstreams: 1 Henrricco Nieves Pujol Tucci.pdf: 3397813 bytes, checksum: c699bbae1cc911a864bb774413e18dec (MD5)
Made available in DSpace on 2017-02-22T21:06:29Z (GMT). No. of bitstreams: 1 Henrricco Nieves Pujol Tucci.pdf: 3397813 bytes, checksum: c699bbae1cc911a864bb774413e18dec (MD5) Previous issue date: 2016-11-21
The aircraft supply is a major cause of flight delays since this process is slow and, if it does not start as soon as the aircraft is available for the maintenance team, the risk of being terminated after the last passenger has already boarded increases. The procedure usually only starts after the information of how much must be supplied get through the flight dispatcher and this information typically take some time to get to the maintenance team. However, it is intended to test a new scenario: start to supply with the minimum quantity of fuel and, if necessary, complete with the amount belatedly informed by dispatcher. Therefore, this paper aims to analyze the application of Six Sigma in this process through the Student's t-test and the Statistical Process Control (SPC). Sigma in this process through the Student t test and Statistical Process Control (SPC). The method adopted was multi cases study by interviews and organizational practices observations. The results showed that the new process is favorable in relation to the former, the Case 1 average time of flight delays has been reduced from 14 to 6 minutes (57%), Case 2 average time has been reduced from 10 to 6 minutes (53%), about flight delays quantity upper than 15 minutes, has reduced to 43% and 39% respectively. It concludes that the application of Six Sigma in aircraft refueling process is innovative to the scientific literature and was favorable for both companies, also helped to mitigate the risk of fines and penalties and, consequently, improved the level of quality of service offered by the airline company.
O abastecimento de aeronaves é uma das principais causas de atrasos de voo uma vez que este processo é lento e, caso este não seja iniciado assim que a aeronave esteja disponível para a equipe de manutenção, o risco de ser finalizado depois do último passageiro já ter embarcado aumenta. O processo de abastecimento usualmente só é iniciado após a informação de quanto se deve abastecer, esta informação costuma demorar a chegar para a equipe de manutenção. A melhoria no processo considera iniciar o abastecimento com a quantidade mínima de combustível e, se necessário, completar com a quantidade tardiamente informada. O objetivo desse trabalho é analisar a aplicação do Seis Sigma utilizando o teste t de Student e o Controle Estatístico do Processo (CEP) nas duas maiores companhias aéreas brasileiras. O método adotado foi estudo de múltiplos casos por meio de entrevista e observação na prática organizacional. O resultado demonstra que o tempo médio de atrasos de voo para o Caso 1 foi reduzido após a aplicação do Seis Sigma, de 14 para 6 minutos (57%). Além disso, a quantidade de atrasos acima de quinze minutos foi reduzida em 53%. Já no Caso 2, o tempo médio foi reduzido de 10 para 6 minutos, uma melhora de 43%, quanto a quantidade de atrasos acima de quinze minutos, houve uma redução de 39%. Conclui-se que a aplicação do Seis Sigma no processo de abastecimento de aeronaves é inovadora para a literatura científica e foi favorável para as duas empresas, também colaborou para mitigar os riscos de multas e penalidades e, consequentemente, melhorou o nível de qualidade do serviço oferecido pelas companhias aéreas.
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25

Koblihová, Simona. "Spokojenost zákazníků v letecké společnosti Travel Service při uplatňování náhrady škody." Master's thesis, Vysoká škola ekonomická v Praze, 2014. http://www.nusl.cz/ntk/nusl-205741.

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The thesis aims to analyze customer satisfaction in the airlines Travel Service in claiming damages. The theoretical part provides the basic concepts of air transport, legislation on civil aviation, the importance of the position of airlines in Czech and foreign aviation market and the introduction of airline Travel Service. The practical part deals with the definition of fundamental rights of air passengers in claiming damages, especially when claiming baggage and delayed or canceled flights. The practical part has been prepared based on the survey of customers Airlines Travel Service In the final part of this thesis compares Travel Service with selected airlines. This thesis uses descriptive method especially in its theoretical part, analysis and comparison method in the practical part.
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26

Zagorodskikh, Sergey. "Single-photon multiple ionisation of atoms and molecules investigated by coincidence spectroscopy : Site-specific effects in acetaldehyde and carbon dioxide." Doctoral thesis, Uppsala universitet, Molekyl- och kondenserade materiens fysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-301128.

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In this thesis, multiple ionisation processes of free atoms and molecules upon single photon absorption are studied by means of a versatile multi-electron-ion coincidence spectroscopy method based on a magnetic bottle, primarily in combination with synchrotron radiation. The latter offered the possibility to access not only valence but also core levels, revealing processes, which promote the target systems into different charge states. One study focuses on double and triple ionisation processes of acetaldehyde (ethanal) in the valence region as well as single and double Auger decay of initial 1s core vacancies. The latter are investigated site-selectively for the two chemically different carbon atoms of acetaldehyde, scrutinising theoretical predictions specifically made for that system. A related study concentrates on core-valence double ionisation spectra of acetaldehyde, which have been investigated in the light of a previously established empirical model, and which have been used as test cases for analysing this kind of spectra by means of quantum chemical electronic structure methods of increasing sophistication. A third study investigates site-specific fragmentation upon 1s photoionisation of acetaldehyde using a magnetic bottle augmented with an in-line ion time-of-flight mass spectrometer. Experimental evidence is presented that bond rupture occurs with highest probability in the vicinity of the initial charge localisation and possible mechanisms are discussed. A site-specificity parameter P∆ is introduced to show that differences in fragmentation behavior between initial ionisations at chemically different carbon atoms probably persist even for identical internal energy contents in the nascent dications. In another study where both electrons and ions from Auger decay of core-excited and core-ionised states of CO2 are detected in coincidence, it is confirmed that O2+ is formed specifically in Auger decay from the C1s → π* and O1s → π* resonances, suggesting a decisive role of the π* orbital in the molecular rearrangement. Also, the molecular rearrangement is found to occur by bending in the resonant states, and O2+ is produced by both single and double Auger decay. A new version of the multi-electron-ion coincidence method, where the ion time-of-flight spectrometer is mounted perpendicularly to the electron flight tube, which affects less the electron resolution and which allows for position sensitive detection of the ions, is employed in combination with tunable soft X-rays to reveal the branching ratios to final Xen+ states with 2 < n < 9 from pure 4d-1, 4p-1, 4s-1, 3d-1 and 3p-1 Xe+ hole states. The coincident electron spectra give information on the Auger cascade pathways.

Byte av lokal vid disputation till Polhemssalen.

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27

Bulat, Muhammer. "Molecular cluster cations of carbon monoxide and carbon dioxide." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2010. http://dx.doi.org/10.18452/16246.

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Diese Dissertation handelt vom metastabilen Zerfall und von der Oberflächenwechselwirkung im hyperthermalen Energiebereich relativ schwach gebundener molekularer Kohlenmonoxid und Kohlendioxid Clusterkationen mit einer Edelstahloberfläche und einer Siliziumoberfläche. Im Rahmen dieser Arbeit wurde ein hierfür geeignetes spezielles Flugzeitmassenspektrometer entwickelt und aufgebaut. Entwurf, numerische Optimierung der Auflösung, ionenoptische Simulationen und Aufbau der jeweiligen Komponenten wie Elektronenquellen, Beschleuniger, Ablenkplatten, Massenfilter und Reflektron werden detailliert beschrieben. Das entwickelte Flugzeitmassenspektrometer besitzt mit einer kompakten Gesamtfluglänge von ~1.5m eine hohe Massenauflösung von m/Delta m = 3000. Es bietet die Möglichkeit, eine Massentrennung von Clusterionen mit einer Größe von bis zu n = 190 vorzunehmen. Diese massenselektierten Clusterionen können daraufhin auf metastabilen Zerfall und auf ihre Wechselwirkung mit einer Oberfläche untersucht werden. Dazu wurden Kohlendioxid-Clusterionen mit n
This thesis deals with the metastable decay and the surface scattering in the hyperthermal energy range of relatively weakly bound molecular cluster cations. With carbon monoxide and carbon dioxide two related model systems were chosen for a systematic size dependent study. Surface impact experiments were carried out with stainless steel and silicon surfaces. Results were obtained by a new, reflectron time-of-flight mass spectrometer (Re-TOFMS). Additional to the experimental data we present in this work a detailed description of the instrumental design considerations, numerical optimization, ion optical simulations. Hence each ion optical component like electron guns, accelerator, deflector, mass gate and reflectron are described. Despite the compact dimensions with a total flight length of ~1.5m the developed instrument possesses a high mass resolution above m/Delta m = 3000. Additionally it offers the possibility to perform mass separation of big cluster ions with sizes n
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28

Luzio, Marco Aurelio. "Study of analytical methods for electron track detection from heavy quark decays generated by sqrt(s)=8TeV pp collisions at ALICE." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-07062017-140205/.

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A study of the usage of ALICEs time of flight (TOF), time projection chamber (TPC), and electromagnetic calorimeter (EMCal), aiming at detecting and separating electrons and positrons (e±) originated from different sources, was carried out. To accomplish the objectives of the research, data gathered from the 2012 proton-proton (pp) collision experiment were used. At a center of mass energy of sqrt(s)=8TeV, the collision of the proton beams liberates heavy quarks, charm and bottom, with approximate lifetimes of approximately 10^13s and 10^12s, respectively. The e± generated through weak semileptonic heavy flavor decays are of interest for studying quarks, therefore it served solely as motivation and incentive for the research carried out and described herein. The introduction of carefully selected cuts, with the purpose of separating partial data collected in the three detectors, permitted the understanding of their effect on the results. Furthermore, due to the fact that the TOFs design was not meant to separate e± from the other heavier particles, only the general effects of introducing a simple cut in the beta=v/c values were analyzed. The more specific cuts were only used for the data generated by the events detected by the TPC and the EMCal. A combination of cuts based on the particles energy loss as a function of traveled distance (dE/dx), with the ratio of energy to momentum (E/p) of the particle, was adopted to enable the separation process, thus allowing for the isolation of e± from the other particles, namely pi±, K±, and p/p. The analysis was performed for values of total particle momentum in the range 0<=p<=6GeV/c. A comparison of the raw data with the results obtained by applying this procedure, indicated a substantial increase in the e± yield and efficiency, reaching average values above 90% over the entire momentum range.
Um estudo do uso dos detetores de tempo de voo (TDV), câmara de projeção de tempo (CPT), e calorímetro eletromagnético (CalEM) do ALICE, visando detectar elétrons e pósitrons (e±) originados por diferentes fontes, foi realizado. Para atingir os objetivos da pesquisa, dados coletados durante o experimento de colisões próton-próton em 2012 foram utilizados. Com um nível de enegia do centro de mass igual a raiz(s)=8TeV, a colisão dos feixes de prótons libera quarks pesados, charm e bottom, com tempo de vida de aproximadamente 10^13s e 10^12s, respectivamente. Os e± gerados pelo decaimento fraco semileptônico de sabores pesados é de interesse para o estudo dos quarks, portanto, o conceito serviu somente como motivação e incentivo para a pesquisa realizada e descrita nesta dissertação. A introdução de cortes específicos, com a finalidade de parcialmente separar dados coletados nos três detectores, permitiu adquirir entendimento sobre os efeitos do cortes nos resultados. Adicionalmente, em virtude do projeto do TDV não ter sido feito visando separar e± oriundos do decaimento dos sabores pesados das demais partículas mais massivas, somente os efeitos gerais de introduzir um corte simples nos valores de beta=v/c, foram analisados. Os cortes mais específicos foram somente nos dados detectados pelo CPT e pelo CalEM. Uma combinação de cortes baseados na perda de energia da partícula em função da distância percorrida (dE/dx), com a razão entre a energia e o momento da partícula (E/p), foi adotada para viabilizar o processo de separação, desta forma permitindo a separação dos e± das demais partículas, ou seja, dos pi±, K±, and p/p. A análise foi realizada para valores de momento total das partículas na faixa 0<=p<=6GeV/c. Uma comparação dos dados originais com os resultados obtidos pela aplicação do procedimento, indicou um aumento substancial do rendimento e eficiência dos e±, atingindo valores médios acima de 90% na faixa inteira de momento.
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29

Ivanov, Georgi. "Freedom of Interpretation." VCU Scholars Compass, 2012. http://scholarscompass.vcu.edu/etd/2808.

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The photographic series Ideal Cities that I started in 2011 is inspired by the conflict between my idea of the “west” and my evolving experience in the United States. What struck me was the popularity of what I see as model experience – a spatial experience controlled by the Spectacle. In the terms of the Situationist International and its most prominent figure Guy Debord, the Spectacle is the collapse of reality into the streams of images, products and activities sanctioned by centralized monopolist business or state bureaucracy. Thus, personal experience is replaced with preconceived notions, which control the way people perceive and understand their surroundings.
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30

CHEN, SHING-YUAN, and 陳行遠. "System Design of Flight Delay Compensation." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/3334dx.

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碩士
東吳大學
資訊管理學系
106
Because of the transparency of the flight information and the development of the blockchain technology in the past few years, flight delay insurance products can be redesigned. The insurance total, delay compensation details, expected time of arrival and the exact time which will cost the airliners to compensate if passed can be written into a smart contract. The blockchain technology could be applied to design a smart contract of flight delay insurance products. Although the factors that cause flight delays are difficult to predict, open and transparent flight information can help optimize flight delay insurance claims processes for automated claims. Flight on-time analysis results also help consumers make decisions and provide comprehensive insurance products services. The purpose of this research is to evaluate the possibility of designing a flight delay compensation system, and the feasibility of applying the blockchain technology to the design. Finally, we investigate the considerations in system design.
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31

Wu, Shih-Wei, and 吳世偉. "Flight-Delay Propagation Forecast--An Application of SIMMOD." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/29822111907358097893.

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碩士
國立交通大學
交通運輸研究所
93
It’s important for airport operators, airlines crew and air traffic controllers(ATC) to predict the flight delays in abnormal weather conditions. In this research, a SIMMOD-based multi-airport simulation model system, including both Taipei and Kaohsiung airports as well as the airspace in between, is developed, calibrated and validated using the ATC data and observed operational data. It is applied for analyzing the performance of airport operations and the flight delays due to runway direction change. The result demonstrates that because of the required transitional operations from one network configuration to the other, only two or three flights could be allowed to use the runway in the first 15 minutes after the runway direction change. As a consequence, the following flights would somehow be delayed. In addition, the simulation shows that if ATC could separate the arrivals effectively, the first departure flight could reduce delay by 21%, and the total propagation time could be shortened. On the basis of the outputs of the simulation, a mathematical delay model is derived. To estimate the expected delays of each flight, for both runway direction change and airport closing, two kinds of delays:push-back delays due to inbound-flight delays or insufficient scheduled ground time, and departure(arrival)delays due to abnormal weather conditions are considered in the model. The departure(arrival)delays of the first flight is subject to the duration of operation transition or airport closing, and the constringency of the delays of the succeeding flights is subject to the difference between the airport capacity and accumulated scheduled flights. Compared to the outputs of the SIMMOD model, the delays derived from the mathematical formulas are rather accurate. The average error is 0.235 minute in five different scenarios. This suggests that the formulas can be used to forecast flight delays, and with this information, better decisions can be made in advance.
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32

Jong, Huey-Tswen, and 鍾惠存. "The Study on Flight-Delay Propagation and Control Strategies." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/81799804112864987156.

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碩士
國立交通大學
運輸工程與管理系
88
This reserch establishes a set of delay-controlled strategies on controlling the propagation of the flight delays caused by incidents. From the view of air transportation, the study explores the propagation conditions of flight delays for different situations, such as connecting flights, gate uses and transfer requirements, and then derives the extent of flight-delay propagation. The past research on flight delays almost focused on flight scheduling, and recovered the flights operation by canceling or adding flights. This research aims at minimizing delay impacts by controlling flight-delays propagation. We formulate the increased cost and time due to flight delay propagation, and discuss how to minimize its impacts by different controlling strategies. The study also develops models to find the most suitable buffer time between flights to control delay propagation.
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33

KUAN, CHEN-YANG, and 官振揚. "CASE STUDY OF AIRCRAFT MAINTENANCE FACTORS AFFECTING FLIGHT DELAY." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/5a9ymd.

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碩士
大同大學
工程管理碩士在職專班
106
In recent years, the Ministry of Transportation and Communications has paid more attentions to flight delays and the allowable delays have been reduced. According to Civil Aeronautics Administration’s flight on-time rate statistics, technical defect occurrences, one of classified delay factors, are likely to be attributed to the airline’s responsibility. Thus the quality of aircraft maintenance has a decisive influence on the flight delay. The data of the flight delays of the twin-engine airliners related to the aircraft maintenance department from 2015 to 2017 were collected. Descriptive statistics, one-way analysis of variance, chi-squared test and cross-analysis were used to analyze time span and frequency of aircraft system and maintenance delay factors. The study found that delays over 30 minutes accounted for 49% of the total delay number. Based on the main classification of aircraft maintenance system, the largest delay number is attributed to airframe systems and the longest average delay time is caused by engines with significant differences. In addition, the number of flight delay due to non-scheduled maintenance is the largest followed by aircraft defect delays, while the aircraft changes cause longest delays. After cross analysis, three groups can be classified according to the delay impact. Air conditioning, hydraulic power, landing gear, engine fuel control are major delay factors. Secondary delay factors include communications, electrical power, flight controls, fuel, navigation and doors. In the end, PDSA was applied to obtain improvement strategy. Through continuing learning and testing in the maintenance process, an effective way would be found to improve maintenance quality and to reduce flight delays.
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34

Chou, Yun-Cheng, and 周昀徵. "Effects of Airline Networks and Airport Dominance on Flight Delay." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/jkc55m.

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碩士
國立交通大學
運輸與物流管理學系
104
This study develops econometric models at low aggregation (segment-carrier) level to investigate the effects of airline network and airport market structure on flight delays in the United States. We develop several measures of airline network and airport market structure. Specially, effects of different connecting passengers of a segment on delays can be examined. The estimation results, verify several hypotheses after the other factors, such as demand, capacity and weather, are controlled. Airline networks and airport dominance have significant effects on flight delays: (a) If the ratio of the second-segment passenger is higher, flight delay increases; (b) If the ratio of the first segment passenger is higher, flight delay decreases; (c) More concentrated connecting passenger would lead to higher delay; (d) Flight delays are internalized at dominated airports; (e) Concentration of alliance do not have significant effect on flight delays. In addition, this paper also illustrates the applications of the models, and clearly shows the different causes of delays of low-cost carriers and full-service carriers. It turns out that the sources of delays of full-service carriers are similar to each other. However, the causes of delays of low-cost carrier are different, especially the ratio of connecting passengers and ratio of full-service carriers in origin airport. In addition, flight delays of low-cost carriers and full-service carriers have increase.
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35

Hsu, Che-Chang, and 許哲彰. "The Study on Flight-Delay Propagation, Allowing for Behavioural Response." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/47525505731339723944.

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碩士
國立交通大學
運輸科技與管理學系
90
ABSTRACT For airlines operating according to published time tables, whenever one flight is delayed, the following flights may be forced to be delayed accordingly, and consequently, results in flight-delay propagation. This study applies probability and statistical methods to model flight delay propagation effects, allowing for behavioral response. From a long-term view point, behavioral response is due to airlines’ estimate of the slack of the time table. Though putting more slack into the time table may improve flight punctuality, it reduces operating efficiency and entails unnecessary waits which cuts the profit potential of airlines. From the instant point of view, behavioral response is also brought upon by actual operators at that instance knowing the flight is delayed. In case of delayed flight, operators can increase their processing speed to minimize the delay. According to characteristics of flight delay propagation, we investigate the following three scenarios in the flight delay propagation model constructed in this research. The first is the flight delay propagation of the same airplane operating the consecutive flights. Because the two flights using the same airplane, the punctuality of the second flight is directly affected by the time the first flight arrives and the time it takes to unload passengers from the first flight and to load passengers for the second flight. The second is the flight delay propagation between different flights and different airplanes when they share the same gate. The punctuality of gate-use start time for the second flight directly depends on when the first flight finishes its gate use and when the airplane of the second flight arrives at the gate. The third scenario is flight delay propagation between different flights and different airplanes when transfers of connecting passengers and luggage are involved. This scenario is similar to the second case. At last, in this research, we use the data of the Airline C shuttle flights serving between Taipei and Hong Kong. In the case study, we first compute the probability distributions of time delays due to flight arrivals and time delays due to ground operations, and then derive the probability distribution of total time delay accounting for both factors. Second, we calibrate the value of the parameter representing the behavioral response due to flight schedules and gaps between flights. Finally, we calculate the probability of flights leaving gate on time, the average wait time of a flight from finishing ground operation to actual taking off, and average delay of the flight take-off time. The results of the study can be valuable references on both estimating flight delays and scheduling flights and slack time for airlines.
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36

Change, Cheng-Min, and 張正民. "Analysis and Design of a Model-Based Flight Control System with Time-Delay." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/75446964302173903491.

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碩士
淡江大學
航空太空工程學系碩士班
100
This paper investigates the development of a distributed multi-microcontroller flight control system for an in-house designed UAV. The flight control computer and other avionic systems and instruments are connected over an I2C (inter-integrated circuit) data bus with the flight control computer as the master micro-controller. The system forms a networked control system. Time delay problem is inevitable when information is transmitted between the micro-controllers. A model-based state feedback flight control system with time delay is presented in the paper. The plant model is used to simulate the plant behavior during the periods when sensor data are not available. When the controller receives the sensor data that were transmitted by the sensor a period of time ago, a propagation unit is employed in the control system to propagate the sensor signals instantaneously to the present time. The estimate is then used to update the model that in turn will generate the control signal for the plant. Computer simulation confirms the success of the model-based design for the distributed multi-chips flight control system.
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37

Kaur, Sukhdeep. "An empirical study of SD signal delay versus temperature in a plenum grade coaxial cable." Thesis, 2010. http://hdl.handle.net/2152/ETD-UT-2010-12-2534.

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A high resolution speedy delivery time domain reflectometer (SD/TDR) has been developed in the Electrical Engineering department at The University of Texas at Austin. The SD/TDR uses a novel non-sinusoidal signal that does not undergo dispersion during transmission in a lossy media. SD/TDR is used to estimate the length and detect the location of faults in the transmission lines. Time of flight (TOF) is one of the critical parameters of SD/TDR and a function of several temperature dependent factors. Given the TOF and length of a transmission line, signal delay can be computed. This research presents an empirical study of the effect of temperature on the TOF in a plenum grade coaxial cable for temperatures ranging from -3 °C to 60 °C. We also study the effect of temperature on characteristic impedance of the coaxial cable. Finally, a SD double exponential waveform is used to estimate TOF for calibrated short and open terminations.
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38

Chiu, Yu-Ping, and 邱郁蘋. "An Equilibrium Model for Airline Flight Cancellations and Airport Flight Delays." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/b265wa.

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碩士
國立交通大學
運輸與物流管理學系
108
This study explores the interaction and equilibrium between flight delays and cancellations from the perspective of airport operations, conducting an empirical study by a competitive airport and simulating the different equilibrium under different levels of competition. The main conceptual framework is as follows: Individual airlines determine the number of canceled flight based on the overall delay of the airport, and the airport delay is affected by the total number of flights of all airlines. This study considers six factors, such as flight delays and traffic volume, competitiveness, route characteristics, weather, and the airport, applies the Heteroskedastic Probit Model to establish individual flight cancellation behaviors and uses GARCH Model to establish airport flight delay model, which obtains equilibrium of airline cancellation rates and flight delays. The results show that (1) queueing delay, volumes, and weather are important factors affecting both departure and arrival delay; (2) delay in hour t is related to the hour t-1 and the hour t-2, in addition, the queuing delay and the scheduled departure and arrival volume have heterogeneous variation; (3) queueing delay has more serious impact on arrival delay than on departure delay, and the marginal effect is increasing; (4) queueing delay, departure delay and arrival delay do increase the probability of flight cancellation; (5) different airlines have different sensitivity to queuing delays in cancellations; (6) as the market goes to more monopoly, the impact of queue delay on the cancellation rate increases significantly. Our equilibrium model which combines the delay model and the cancellation model truly could run and interact, and the prediction error is within the acceptance range that could be used to simulate the scenario. Compared with the current situation (3.8 workable competitors), when the airport becomes a monopoly, the cancellation rate increases by 9.5 percentage points; the changed ratios of cancellation rate is 111.76%; the departure delay decreased by 2%. It is obvious that the importance of the impact of competition on flight cancellation and delay. The more monopoly the airport is, the more likely the airline will internalize the cost of delay by canceling flights.
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39

Victor, Colette. "The influence of flight delays on business travellers." Diss., 2010. http://hdl.handle.net/2263/27988.

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The main aim of the study was to assess the influence of flight delays on business travellers. Studies on flight delays have been done from a number of perspectives; these include the reasons for flights delays, the costs to airlines and airports, the effect on airline scheduling and the impact on airline market share. An area that has received little, if any, attention is the impact of flight delays on business travellers, one of the most lucrative markets for airlines. This study empirically researches the direct cost of flight delays to travellers of a specific corporation. In addition, the use of mobile technology in communicating the occurrence of flight delays to business travellers, and how this could alleviate traveller frustrations, are discussed from a theoretical perspective. The study followed a quantitative methodology to determine man-hours lost and the direct costs of flight delays to travellers from a selected corporation. Two data sets were used, one provided by the corporation on flights undertaken by their corporate travellers over a predetermined period, the other by the Air Traffic and Navigation Services (ATNS) on all flights over the same period. The two sets of data were matched and analysed to determine which flights undertaken by the corporate travellers were delayed, based on actual arrival times, and if any significant relationships could be determined between flight delays and types of traveller (frequent versus infrequent) or specific time periods (time of day, day, week and month). The results indicated that frequent travellers experienced the majority of flight delays, and consequently represented the greatest cost to the corporation. The study also found significant relationships between substantial delays and the month of the year, day of the week, and the time of day flown. The identification of patterns could provide business travellers with the information to better manage their travel arrangements and optimise their travel times and costs. In calculating the direct monetary cost, the value of time lost was found not to constitute a substantial amount to the corporation, but this result must be viewed against the limitations of the study. This study serves to provide a foundation for future research into the cost of flight delays to business travellers. Future research should include larger samples (large global or multiple companies could be used) and extend the time periods for assessing delays. Future studies could also include other direct and indirect costs not covered here and the study could be replicated in different geographical areas, particularly areas with a high density of flights such as Asia, the United States of America and Europe. Copyright
Dissertation (MCom)--University of Pretoria, 2010.
Tourism Management
unrestricted
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40

Ning, Wu Wei, and 吳唯寧. "Alleviation of Flight Delays Through Passenger Arrangement Mechanisms." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/56389209675893187964.

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碩士
逢甲大學
運輸科技與管理學系
103
Airline daily operations are often limited by delay concerns. The duration of flight delay is difficult to accurately estimate and thus, might certainly cause inconvenience to air travelers for completing their trips in punctual manner. The purpose of this study is to identify the travelers’ preference for passenger arrangement mechanisms under flight delay situations. This study uses the stated preference method which considers a set of attributes, including duration of delay, monetary compensation, snacks and beverages, cabin class upgrade, free airport lounges and free hotel, to capture the passengers’ preferences for alternative arrangements. An integrated model is developed using the cumulative prospect theory combined with the discrete choice model that identifies significant attributes. Approximately 800 distributed questionnaires were collected from the Taiwanese air travelers who took the full-service carriers at the Taiwan Taoyuan International Airport. The result showed that if a major flight delay occurs and the airline wish the passengers to stay with the booked flight, the airlines need to maintain a good long-term relationship with their passengers by offering exclusive arrangements, such as free meals and, more importantly, free lounge and hotel service in long-distance travel. If the booked flight cannot resume operation in time, the airline company could assist high priority passengers to take the next flight by the same airline or transfer to another airline. An effective scheme is to offer fare discount to typical passengers who are willing to fly business class and a free grade to frequent flyers.
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41

Tsai, Shy-Chang, and 蔡世昌. "A Causal Model for Flight Delays in an Airline Network." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/78416409464037410041.

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博士
國立交通大學
交通運輸研究所
101
Flight delays are a source of great concern as they generate disruptions and increase costs for airlines and passengers. The aim of this research is to propose approaches to examine flight delay propagation in a multiple-airport environment and to evaluate the effectiveness of delay improvement schemes adopted by airlines. Due to the stochastic characteristics of turnaround and block operations, this research investigates the factors behind the mechanisms of departure and arrival delays to clarify the phases and activities involved in flight delays through an airline schedule. The Cox proportional hazards model, a method widely applied in survival analysis, is used to develop departure and arrival delay models involving a Taiwanese domestic airline. The proposed models show how flight delay propagation can be formulated through repeated chain effects in aircraft rotations. The results shows that whilst outbound flights are subject to a wider range of difficulties leading to delays, inbound flights can be delayed by weather or air traffic control restrictions en-route or at destination airport. Hence, most arrival delays are beyond the control of airlines except for delays that develop at departure airports. This implies that developing the means to prevent departure delays could be the key to reducing arrival delays from the origin. The hazard ratios obtained provide measures of the chances of recovering from flight delays under a variety of situations and the effects that individual contributing factors of flight delays have on airline schedule reliability. To manage flight delays, airlines are prepared for the unexpected stochastic events of turnaround and block operations. This research further uses the obtained departure and arrival delay models to examine delay improvement schemes, including shorting required ground handling time and increasing buffer time for turnaround and en-route aircraft. The costs of schemes and the savings of delay costs are investigated to evaluate the net benefits of schemes by recursively combining the departure and arrival delay models. Though buffer time may save some delays, it is found that it may not be cost effective for airlines when the costs of buffer minutes are taken into account. The results also reveal that delays may not be greatly improved through this measure in the dynamic operating environment. Thus, airlines may investigate the significant contributing factors of delays and design a suitable delay management program before jumping into some sophisticated measures. The findings provide a better understanding of the relationship between planned schedules and delay propagation, and are thus useful for schedule control and delay management.
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42

Hou, Yu-chou, and 侯育周. "An Approach for Dynamic Airport Gate Assignments for Stochastic Flight Delays." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/69152698007108137980.

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碩士
國立中央大學
土木工程研究所
95
In actual operations, stochastic flight delays (such as early or late arrivals and late departures) often occur, causing real time stochastic disturbances which disrupt the planned gate assignments. As a conscquence, the disrupted flights may not be assigned to their original gates, meaning the airport authority needs to reassign the flights in real-time. How to assist the airport authority to effectively reassign gates given stochastic flight delays is an important research topic. In addition, stochastic flight delay information may vary with time. The consideration of such information in the reassignment process however would produce a better reassignment result, making for more practical real world stochastic flight delays. We develop a stochastic flight delay gate reassignment model for the airport authority’s perspective. We first develop a dynamic gate reassignment framework, which combined the stochastic flight delay gate reassignment model, can solve gate reassignment problems by incorporating varied information about stochastic flight delays. It is expected to that this is a useful tool for authorities to effectively handle gate reassignments and thus enhance current airport operations. Mathematical programming techniques are used to formulate the stochastic flight delay gate reassignment model, and a dynamic gate reassignment process is developed. In addition, a deterministic flight delay gate reassignment model is also developed, to evaluate the performance of the stochastic flight delay gate reassignment model and the dynamic gate reassignment framework. We also perform a case study using data from a Taiwan international airport. Finally some conclusions and suggestions are given.
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43

Chen, Yun-Hsuan, and 陳昀暄. "Determinants of Flight Delays in East Asia: Airport, Route, and Network." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/r9hd9z.

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碩士
國立臺灣大學
地理環境資源學研究所
107
In the last decade, air traffic volume in East Asia has increased rapidly, and flights in the region suffer from severe delays. Nevertheless, most previous studies on flight delay determinants were conducted in North America and Europe, and very few of them were based on East Asia. Furthermore, previous research focused on such determinants from airport and route perspectives and disregarded the network perspective (i.e., influence of “connected airports”). This study aims to explore the determinants of flight delays in East Asia, and it covers not only airport and route determinants explored in previous research but also those regarding directly connected airports to include the network perspective. This study adopts panel data regression models to verify how the variables of the three perspectives influence flight delays in East Asia. The flight data of 4,611 routes among 318 airports in the second half of 2017 are used. The daily average arrival delay of routes is employed as the dependent variable, and three perspective and control variables are utilized as independent variables. The empirical findings indicate that from the airport perspective, congestion internalization and the “hubness” effect suggested in previous research do not exist in East Asia. The route variables affect delays in various countries and route types differently, and connected airports are crucial determinants of flight delays in East Asia. These findings imply that the experiences of and theories from North America and Europe are inapplicable in explaining flight delays in East Asia. This study not only addresses the gap in existing literature but also provides a meaningful basis for the establishment of airport congestion tax, aircraft deployment, and other operational carrier strategies for East Asia.
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44

Li, Sui-Ling, and 李穗玲. "Optimization Models for Estimating Airport Runway Capacity and Assessing Flight Technical Delays." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/11966133392350016221.

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博士
國立交通大學
交通運輸研究所
89
Runway capacity estimation is the basic foundation for air traffic flow management in airport. The level of flight delays at airports affects not only passengers and the quality of airline service, but it also the performance of air traffic management. Therefore, there are four objects in this study, which estimate runway capacity, assess flight technical delay, evaluate airlines’ punctuality performance, and modify schedule timetable. First, this research is not only applying the statistics to analyze the separated value between take-off and landing craft types but also using mathematical programming to consider the demand of take-off and landing, the constrict of the relation between take-off and landing type, to estimate take-off /landing composed type and the optimal runway capacity. Our study is suitable to estimate runway capacity in the good weather not only estimating the frequency between take-off and landing aircraft on runway but also making a strategy for time-slot management problem. Second, this study seeks to clarify the causes, as well as measurements of approach delays. Furthermore, this study also examines the impacts of technical delays and scheduled system delays in measuring the performance of air traffic management. We also consider both the capacity constraints of a runway and the arrival/landing approach routes, using mathematical planning to construct a static-and-theoretical delay analysis of the optimization model. The availability of this model is clarified and tested to evaluate the performance of air traffic management by means of simulating the different service rules of actual flight delays. The outcome of the example shows that the estimate of the optimization model for each aircraft delay is higher than the estimate using the FIFS rule. However, the optimization model for each aircraft delay is probably either higher or lower than that for the arrival priority rule. The delay value of both FIFS and arrival priority are highly related to the delay value of the optimization model. By means of regression analysis and testing, the outcome of forecasted numbers are all within a 95% confidence interval. This proves the efficacy of the optimization model for correctly estimating actual flight delays. Third, this study introduces both the technical delay and timetable system delay to evaluate and modify the airlines’ punctuality. A model for evaluating the performance of airlines’ punctuality is proposed. The punctuality should not be measured by 15 minutes. It should take the constraints of airport capacity and flight timetable put consideration. At last, this study can assist timetable planning of minimum delays, choose the suitable time points and arrange suitable aircraft numbers and sequences, also proposes the planning strategies of scheduled timetable and enhance the value of available surplus capacity to analyze and arrange vacant rule of flight take-off/landing runway on the timetable.
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45

Feiteira, Inês Viana. "Predictive modelling : flight delays and associated factors hartsfield–Jackson Atlanta international airport." Master's thesis, 2018. http://hdl.handle.net/10362/42529.

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Project Work presented as the partial requirement for obtaining a Master's degree in Information Management, specialization in Knowledge Management and Business Intelligence
Atualmente, um ponto negativo nas viagens de avião são os atrasos que, constantemente, são anunciados aos passageiros resultando numa diminuição da sua satisfação enquanto clientes. Este e outros fatores fazem com que elevados custos, tanto quantitativos como qualitativos sejam imputados às companhias. Consequentemente, existe a necessidade de prever e mitigar a existência de atrasos aéreos que pode ajudar as companhias aéreas bem como aeroportos a melhorar a sua performance e a aplicar algumas medidas, dirigidas ao consumidor, que permitiam atenuar ou até anular o efeito que estes atrasos provoca nos seus passageiros. Deste modo, este estudo tem como principal objetivo prever a ocorrência de atrasos nas chegadas ao aeroporto internacional de Hartsfield-Jackson. Esta estimativa será possível através da elaboração de um modelo preditivo, recorrendo a diversas técnicas de Data Mining. Com a aplicação destas técnicas, foi possível identificar as variáveis que mais contribuíram para a existência do atraso. No desenvolvimento deste trabalho, foi seguida a metodologia da descoberta de conhecimento em base de dados (conhecida em inglês por Knowledge Discovery Database, KDD). Fases como a recolha dos dados, a aplicação de técnicas de amostragem (SMOTE e Undersampling), a partição dos dados em treino e teste, o pré-processamento (dados omissos e outliers) e transformação dos dados (normalização dos dados e seleção de atributos), a definição de modelos a treinar (Decision Trees, Random Forest e Multilayer Perceptron) bem como a avaliação da performance dos modelos através de métricas variadas foram aplicadas. Depois de testar diferentes abordagens, concluiu-se que o melhor modelo é alcançado com as variáveis relacionadas com a partida, usando o algoritmo Multilayer Perceptron e aplicando a técnica de SMOTE para lidar com dados não balanceados, removendo outliers e selecionando dez variáveis usando GainRatio. Por outro lado, quando as variáveis com informação da partida são excluídas, o algoritmo que melhor se destaca é o Multilayer Perceptron usando a técnica SMOTE, mas desta vez, incluindo os outliers e com quinze variáveis selecionadas novamente pelo GainRatio. Em ambas as hipóteses, as variáveis explicativas que mais contribuem para a existência do atraso na chegada são relacionadas com o clima, com as características do avião e com a propagação do atraso. Os resultados do algoritmo de Random Forests mostraram melhor desempenho, em relação à precisão, em comparação com outros autores (Belcastro, Marozzo, Talia, & Trunfio, 2016; Choi, Kim, Briceno, & Mavris, 2016). Contrariamente, o algoritmo Multilayer Perceptron, apresentou menor precisão em comparação com outro estudo equivalente (Y. J. Kim, Choi, Briceno, & Mavris, 2016).
Nowadays, a downside to traveling is the delays that are constantly advertised to passengers resulting in a decrease in customer satisfaction. These delays associated with other factors can cause costs, both quantitative and qualitative. Consequently, there is a need to anticipate and mitigate the existence of airborne delays that can help airlines and airports improving their performance or even take some consumer-oriented measures that can undo or attenuate the effect that these delays have on their passengers. This study has as primary objective to predict the occurrence of arrival delays of the international airport of Hartsfield-Jackson. It was possible by building a predictive model, applying several Data Mining techniques. With these applications, it was possible to show the variables, among the proposals, that most contributed to the existence of the delay. In this work, the Knowledge Discovery Database (KDD) methodology was followed. Phases such as data collection; sampling techniques (SMOTE and Undersampling); Data partitioning in training and testing; Pre-processing (missing data and outliers) and data transformation (data normalization and attribute selection); And, finally the definition of models to be trained (Decision Trees, Random Forests, and Multilayer Perceptron), as well as the evaluation of the performance of the models through varied metrics, were used. After testing different approaches, it was concluded that the best model is achieved with the variables related to departure, using the Multilayer Perceptron algorithm and applying SMOTE to deal with unbalanced data, removing outliers and selecting ten variables using GainRatio. On the other hand, when the variables with information of the departure are excluded, the algorithm that performs best is also the Multilayer Perceptron using the SMOTE technique but, this time, including the outliers and with fifteen variables selected again by the GainRatio. On both hypotheses, the explanatory variables that most contributed to the existence of the delay in arrivals were related to the weather, the airplane characteristics and the propagation of the delay. Our results for the Random Forests algorithm shown better performance, regarding accuracy, compared to other authors (Belcastro et al., 2016; Choi et al., 2016). Contrary, for the Multilayer Perceptron algorithm, was presented a lower accuracy compared to another equivalent study (Y. J. Kim et al., 2016).
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46

Amoreira, Joana Da Rocha Tomé Baptista. "A deep analysis into flight delays´ problematic: tendancys, root causes and ultimate implications." Master's thesis, 2021. http://hdl.handle.net/10362/123038.

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A Deep Analysis into Flight Delays’ Problematic: Tendencies, Root Causes and Ultimate Implications Airline industry has been experiencing a considerable increase in demand over the years. However, one of the biggest challenges currently faced by airlines is the industry’s inability to adjust the supply to demand’s growth, as increase in airports’ capacity is limited. Such result in a higher capacity utilization and, consequently in an increased disruption in processes, being flight delays the main problematic arising from that. Considering this, this study will statistically analyse multiple factors, reaching conclusions on flight delays’ tendencies, root causes and implications ,in order to ultimately provide recommendations to minimize such problematic by turning processes more efficient.
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47

Fernandes, Nuno Óscar Gomes. "A study on the prediction of flight delays of a private aviation airline." Master's thesis, 2017. http://hdl.handle.net/10071/15447.

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The delay is a crucial performance indicator of any transportation system, and flight delays cause financial and economic consequences to passengers and airlines. Hence, recognizing them through prediction may improve marketing decisions. The goal is to use machine learning techniques to predict an aviation challenge: flight delay above 15 minutes on departure of a private airline. Business and data understanding of this particular segment of aviation are revised against literature revision, and data preparation, modelling and evaluation are addressed to lead towards a model that may contribute as support for decision-making in a private aviation environment. The results show us which algorithms performed better and what variables contribute the most for the model, thereafter delay on departure.
O atraso de voo é um indicador fulcral em toda a indútria de transporte aéreo e esses atrasos têm consequências económicas e financeiras para passageiros e companhias aéras. Reconhecê- los através de predição poderá melhorar decisões estratégicas e operacionais. O objectivo é utilizar técnicas de aprendizagem de máquina (machine learning) para prever um eterno desafio da aviação: atraso de voo à partida, utilizando dados de uma companhia aérea privada. O conhecimento do contexto do negócio e dos dados adquiridos, num segmento singular da aviação, são revistos à luz das literatura vigente e a preparação dos dados, a modelização e respectiva avaliação são conduzidos de modo a contribuir para uma ferramenta de apoio à decisão no contexto da aviação privada. Os resultados obtidos revelam quais dos algoritmos utilizados demonstra uma melhor performance e quais as variáveis dos dados obtidos que mais contribuem para o modelo e consequentemente para o atraso à partida.
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48

Lai, Yi-Shan, and 賴奕杉. "An Approach for Conformity Airport Gate Assignments for Stochastic Flight Delays And Decomposition Algorithm." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/52070883977042209544.

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碩士
國立中央大學
土木工程研究所
96
The assignment of flights to gates is essential to an airport,s operation and level of service. However, stochastic flight delays often occur in real world. The aircraft may not be assigned to the planned gate due to the stochastic flight delays in real operations. As a result, an airport staff has to reassign flights to gates in real-time operations and the actual performance of the original assignments could be reduced. Therefore, considering of stochastic flight delays is necessary in actual operations. It also helps airport authority to handle the assignment of flights to gates and improve the performance of gate assignment problem. A integrated framework which contain the gates planning and the real-time stages, is introduced to solve the stochastic programming problem. We develop the perfect information model and the gate reassignment model base on a integrated framework. The two models solve the stochastic flight delay. First, the perfect information model is established based on the concept of perfect information. Second, the stochastic model considers of prioritize time of the flight assignment. It is expected to that this is a useful tool for authorities to effectively handle gates reassignment and thus enhance current airport operation. We also study optimality of integrated problems except for developing two models. Besides, the two models could not solve large-scale problems optimally by using mathematics programming software. In order to solve large-scale problems efficiently, we develop decomposition algorithms each for these two models. The stochastic model is nonlinear mathematics programming program. The preliminary results are good, showing that the models could be useful for a Taiwan international airport.
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49

Bryan, Jon Lance. "An analysis of student programmatic delays in postsecondary flight training programs: A national study." 1996. https://scholarworks.umass.edu/dissertations/AAI9638936.

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The purpose of this study was to determine the number of University Aviation Association (UAA) member postsecondary institutions that were experiencing student delays in flight certification. Such delays can lead to increased costs for the student, the failure to complete the intended academic program, and an interruption in career progression. This study queried the aviation program administrators of UAA member flight institutions to determine the extent of the problem. Through a questionnaire, the researcher determined whether a relationship existed between student flight curriculum progress and certain identified factors at those institutions. A survey instrument was used to obtain responses to questions such as: the level of flight student progress delays, institutional policies regarding prepayment for flight services, the number of students failing to complete their flight training in the semester predicated by the syllabus, the impact of weather and finances, the use of ground-based training devices, and institutional policies relating to flight student incomplete grades. The study revealed that approximately 88% of the respondents noted that they were experiencing a problem with flight student progress delays at their institution. The research indicated that institutional financial policies, such as the formal determination of flight student finances in advance of each semester, were factors in reducing "Major" progress delays. The use of simulation or ground-based training devices was associated with a reduction in the flight progress delays. Flight instructor turnover was not a substantial factor in the student training delays. No relationship was noted between the incidence of flight student progress delays and the level of degree offered at the postsecondary institutions. A larger percentage of the flight student progress delays were classified as "Major" at two-year rather than at four-year institutions.
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50

Kreibich, Dan Andreas. "Flightright now : development of a predictive legal service for the compensation of flight delays in realtime." Master's thesis, 2017. http://hdl.handle.net/10362/21680.

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Internship Report presented as the partial requirement for obtaining a Master's degree in Information Management, specialization in Information Systems and Technologies Management
Legal technology is a relatively recent discipline, which refers to providing legal services with the help of technology and software. One of the biggest players in this field is Flightright GmbH, a German company which focusses on helping air passengers to receive compensation from airlines in case of flight disruptions. Companies in the market of air passenger rights offer different services with compensation options ranging from 24 hours up to several months. Striving for a pioneer product in the legal technology market, the Flightright Now project has created the globally first service offering real-time customer compensation. This project, the development of Flightright Now, was the center of my internship at Flightright GmbH. Comprising several business- and IT-related topics the focus was placed on project management in software development and predictive analytics. The report results in key lessons learned during project conduction.
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