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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Utvärdering av Transportstyrelsens flygtrafiksmodeller

Arvid, Odencrants, Dennis, Dahl January 2014 (has links)
The Swedish Transport Agency has for a long time collected data on a monthly basis for different variables that are used to make predictions, short projections as well as longer projections. They have used SAS for producing statistical models in air transport. The model with the largest value of coefficient of determination is the method that has been used for a long time. The Swedish Transport Agency felt it was time for an evaluation of their models and methods of how projections is estimated, they would also explore the possibilities to use different, completely new models for forecasting air travel. This Bachelor thesis examines how the Holt-Winters method does compare with SARIMA, error terms such as RMSE, MAPE, R2, AIC and BIC  will be compared between the methods.  The results which have been produced showing that there may be a risk that the Holt-Winters models adepts a bit too well in a few variables in which Holt-Winters method has been adapted. But overall the Holt-Winters method generates better forecasts . / <p>Avbryt / Spara utkast</p>
2

ATC complexity measures: Formulas measuring workload and complexity at Stockholm TMA

Dervic, Amina, Rank, Alexander January 2015 (has links)
Workload and complexity measures are, as of today, often imprecise and subjective. Currently, two commonly used workload and complexity measuring formulas are Monitor Alert Parameter and the “Bars”, both using the same measurement variables; amount of aircraft and time. This study creates formulas for quantifying ATC complexity. The study is done in an approach environment and is developed and tested on Stockholm TMA by the creation of 20 traffic scenarios. Ten air traffic controllers working in Stockholm TMA studied the complexity of the scenarios individually and ranked the scenarios in reference to each other. Five controllers evaluated scenario A1-A10. These scenarios were used as references when creating the formulas. The other half of the scenarios, B1-B10, ranked by another five controllers, was used as validation scenarios. Factors relevant to an approach environment were identified, and the data from the scenarios were extracted according to the identified factors. Moreover, a regression analysis was made with the ambition to reveal appropriate weights for each variable. At the first regression, called formula #1, some parameter values were identical. Also, some parameter weights became negative in the regression analysis. The basic requirements were not met and consequently, additional regressions were done; eventually forming formula #2. Formula #2 showed stable values and plausible parameter weights. When compared to a workload measuring model of today, formula #2 showed better performance. Despite the small amount of data samples, we were able to prove a genuine relation between three, of each other independent, variables and the traffic complexity.
3

Analys av svårigheter med att driva flygplatsskyltar på seriekrets / An analysis of the difficulties of running airfield signs on a series circuit

Wahlström, Erik January 2003 (has links)
<p>Vid idrifttagning av banljussystemet på Bana 3, Arlanda flygplats, uppstod vissa driftsproblem. Problemen yttrade sig så att de regulatorer, så kallad CCR (Constant Current Regulator), som försörjer informations- och anvisningsskyltar, löste ur för framförallt överström. Det berodde på att kretsen var ovanligt oscillativ. Problemen uppstod enbart på de kretsar som hade skyltar som last. Som belysning i skyltarna används lysrör. </p><p>Kretsen skiljer sig från vanliga belysningssystem på det viset att det är en seriekrets. Seriesystemet har flera fördelar jämfört med ett traditionellt parallellsystem, bland annat att det är billigare och enklare att bygga. Det gör då att istället för en konstant spänning finns en konstant ström att tillgå i kretsen. Detta gör att man måste omvandla strömmen till en konstant spänning, för att kunna driva lysrören. Vanliga lampor är inte beroende av en konstant spänning för att lysa. </p><p>Rapporten presenterar hur en seriekrets är uppbyggd och vad det finns för komponenter i just denna anläggning på Arlanda. Vidare presenteras funktionen för de olika komponenterna, och hur de påverkar omgivningen. </p><p>Utförda mätningar på Arlanda används, tillsammans med information från tillverkare, som grund för en analys av systemet. Utgående från resultatet av denna analys presenteras förslag på åtgärder.</p>
4

Kapacitets- och känslighetsanalys av bagagehanteringssystem på Arlanda flygplats / Capacity and sensitivity analysis of luggage handling system at Stockholm-Arlanda airport

Bernandersson, Martin January 2005 (has links)
<p>Detta är en kapacitets- och känslighetsanalys av bagagehanteringssystem vid Arlanda flygplats. Studien är ett examensarbete för civilingenjörsutbildningen Kommunikations- och Transportsystem vid Linköpings universitet och är utförd på uppdrag av Luftfartsverket, LFV Teknik under 2004 och 2005. </p><p>Studien har gjorts med datorstödd simulering som analysverktyg. Studien har gjorts genom att en simuleringsmodell av det studerade systemet har byggts i simuleringsprogrammet Arena. Denna modell har matats med trafikunderlag från en normalvecka under 2004. Utifrån denna modell och utifrån förväntade trafikökningar har sedan ett antal kapacitets- och känslighetsanalysscenarier formulerats och dessa har sedan simulerats och resultaten har tolkats och analyserats samt jämförts med resultaten från grundmodellen. </p><p>Kapacitetsanalysen visar att anläggningen är väl rustad för att ta emot den annalkande trafikökning som förväntas under de närmaste åren, eftersom den ökade trafiken inte innebär några signifikanta problem genom ökat antal väskor som inte hinner med sina flighter. Det som dock kan vara en begränsande faktor är att fickallokeringssystemet inte är effektivt och det sänker anläggningens verkliga kapacitet. För att kunna nyttja anläggningen maximalt bör fickallokeringssystemet ses över. </p><p>Känslighetsanalysen visar att systemet är mycket sårbart för störningar, särskilt om kommunikationen med BSM-centralen går ner eller om en Röntgen Level 2-maskin går sönder. Sådana händelser resulterar i att anläggningens kapacitet minskar kraftigt och i vissa fall klarar anläggningen inte av att hantera dagens trafikmängd. En handlingsplan för hur dessa störningar och konsekvenserna av dem ska minimeras bör införas snarast. </p> / <p>This is a capacity and sensitivity analysis of a baggage handling system at Stockholm-Arlanda airport. The study is a Master's Thesis in Communication and Transport Systems Engineering at the University of Linköping. The study was done on behalf of the Swedish Civil Aviation Administration. The analysis tool that was used is simulation. </p><p>In the study, a simulation model of the baggage handling system was implemented in the simulation program Arena. A base scenario containing the traffic program from one week in 2004 was created and used as a reference scenario. A total of 8 different scenarios were created to form the capacity and sensitivity analyses. </p><p>The capacity analysis showed that the baggage handling system will be able to handle the forecasted increases in traffic over the next few years with relative ease. The X-ray machines are currently not working at anywhere near full capacity. However, the system is currently not being used in an efficient way. The pocket allocation method is far from optimal because flights that use more than one pocket are allocated adjacent pockets only which can be very inefficient. This method needs to be revised for the system to work efficiently. </p><p>The sensitivity analysis showed that the system is very vulnerable if certain things happen. In particular if the communication link with the Baggage Source Message-central in London is lost there will be big problems because all luggage will go to the Manual Encoding Station (MES). The MES will then be very digested and it will take a considerably larger amount of time for the baggage to pass through the system. Problems will also occur if one of the two Level 2 X-ray-machines break down. The remaining machine cannot handle all the baggage by itself, especially not if there are flights to the USA about to depart since baggage heading for the USA must be run through X-ray Level 2. It is strongly recommended that handling plans are formed to minimise the effects of such events.</p>
5

Kapacitets- och känslighetsanalys av bagagehanteringssystem på Arlanda flygplats / Capacity and sensitivity analysis of luggage handling system at Stockholm-Arlanda airport

Bernandersson, Martin January 2005 (has links)
Detta är en kapacitets- och känslighetsanalys av bagagehanteringssystem vid Arlanda flygplats. Studien är ett examensarbete för civilingenjörsutbildningen Kommunikations- och Transportsystem vid Linköpings universitet och är utförd på uppdrag av Luftfartsverket, LFV Teknik under 2004 och 2005. Studien har gjorts med datorstödd simulering som analysverktyg. Studien har gjorts genom att en simuleringsmodell av det studerade systemet har byggts i simuleringsprogrammet Arena. Denna modell har matats med trafikunderlag från en normalvecka under 2004. Utifrån denna modell och utifrån förväntade trafikökningar har sedan ett antal kapacitets- och känslighetsanalysscenarier formulerats och dessa har sedan simulerats och resultaten har tolkats och analyserats samt jämförts med resultaten från grundmodellen. Kapacitetsanalysen visar att anläggningen är väl rustad för att ta emot den annalkande trafikökning som förväntas under de närmaste åren, eftersom den ökade trafiken inte innebär några signifikanta problem genom ökat antal väskor som inte hinner med sina flighter. Det som dock kan vara en begränsande faktor är att fickallokeringssystemet inte är effektivt och det sänker anläggningens verkliga kapacitet. För att kunna nyttja anläggningen maximalt bör fickallokeringssystemet ses över. Känslighetsanalysen visar att systemet är mycket sårbart för störningar, särskilt om kommunikationen med BSM-centralen går ner eller om en Röntgen Level 2-maskin går sönder. Sådana händelser resulterar i att anläggningens kapacitet minskar kraftigt och i vissa fall klarar anläggningen inte av att hantera dagens trafikmängd. En handlingsplan för hur dessa störningar och konsekvenserna av dem ska minimeras bör införas snarast. / This is a capacity and sensitivity analysis of a baggage handling system at Stockholm-Arlanda airport. The study is a Master's Thesis in Communication and Transport Systems Engineering at the University of Linköping. The study was done on behalf of the Swedish Civil Aviation Administration. The analysis tool that was used is simulation. In the study, a simulation model of the baggage handling system was implemented in the simulation program Arena. A base scenario containing the traffic program from one week in 2004 was created and used as a reference scenario. A total of 8 different scenarios were created to form the capacity and sensitivity analyses. The capacity analysis showed that the baggage handling system will be able to handle the forecasted increases in traffic over the next few years with relative ease. The X-ray machines are currently not working at anywhere near full capacity. However, the system is currently not being used in an efficient way. The pocket allocation method is far from optimal because flights that use more than one pocket are allocated adjacent pockets only which can be very inefficient. This method needs to be revised for the system to work efficiently. The sensitivity analysis showed that the system is very vulnerable if certain things happen. In particular if the communication link with the Baggage Source Message-central in London is lost there will be big problems because all luggage will go to the Manual Encoding Station (MES). The MES will then be very digested and it will take a considerably larger amount of time for the baggage to pass through the system. Problems will also occur if one of the two Level 2 X-ray-machines break down. The remaining machine cannot handle all the baggage by itself, especially not if there are flights to the USA about to depart since baggage heading for the USA must be run through X-ray Level 2. It is strongly recommended that handling plans are formed to minimise the effects of such events.
6

Analys av svårigheter med att driva flygplatsskyltar på seriekrets / An analysis of the difficulties of running airfield signs on a series circuit

Wahlström, Erik January 2003 (has links)
Vid idrifttagning av banljussystemet på Bana 3, Arlanda flygplats, uppstod vissa driftsproblem. Problemen yttrade sig så att de regulatorer, så kallad CCR (Constant Current Regulator), som försörjer informations- och anvisningsskyltar, löste ur för framförallt överström. Det berodde på att kretsen var ovanligt oscillativ. Problemen uppstod enbart på de kretsar som hade skyltar som last. Som belysning i skyltarna används lysrör. Kretsen skiljer sig från vanliga belysningssystem på det viset att det är en seriekrets. Seriesystemet har flera fördelar jämfört med ett traditionellt parallellsystem, bland annat att det är billigare och enklare att bygga. Det gör då att istället för en konstant spänning finns en konstant ström att tillgå i kretsen. Detta gör att man måste omvandla strömmen till en konstant spänning, för att kunna driva lysrören. Vanliga lampor är inte beroende av en konstant spänning för att lysa. Rapporten presenterar hur en seriekrets är uppbyggd och vad det finns för komponenter i just denna anläggning på Arlanda. Vidare presenteras funktionen för de olika komponenterna, och hur de påverkar omgivningen. Utförda mätningar på Arlanda används, tillsammans med information från tillverkare, som grund för en analys av systemet. Utgående från resultatet av denna analys presenteras förslag på åtgärder.
7

Effects of Complexity Factors on Controllers Workload in Stockholm Terminal Area

Zohrevandi, Elmira January 2016 (has links)
Through a history of more than 50 years, the results of mathematical models have shown that controller workload is being driven by the complexity involved in the airspace environment. Part of this complexity is prompted by the dynamical behavior of traffic patterns. From the results of models describing controller’s workload, it is observed that predictability decreases the complexity. Therefore, the general idea behind this topic is to analyze how a specific notion of predictability influences the controller’s workload. This specific notion in this research is a type of automation that aircraft benefit from. In a more specific sense, the goal of this research was to analyze how the controllers handle the air traffic in different complex situations when exposed to different automation levels. The following dilemmas are focused through this work: - Information visualization of controllers’ interaction with radar screen - Quantification of dynamics of air traffic patterns - Modeling and quantification of controllers’ workload First, in order to have a grasp of the controllers’ interaction with the air traffic patterns, the controllers’ activities on the radar screen have been visualized in chapter 2. The visualization results for different automated conditions have been analyzed. Based on such analysis the criteria for problem space has been addressed and the main research question is identified. Next in chapter 3, the airspace complexity caused by air traffic flow has been studied and a set of known complexity factors are quantified using a novel calculation approach. With a logistics perspective toward airspace complexity, to calculate each complexity factor, a mathematical formulation has been used and the effects of each corresponding factor on controllers’ workload are addressed. Then in chapter 4, a novel approach toward modeling controller’s workload is presented. After implementing the model on 18 different scenarios, a model for controller’s workload has been developed in which around 60 percent of the en-route air traffic complexity values and around 80 percent of terminal air traffic complexity values could be well-matched with the workload values. From statistical point of view, the results are very much acceptable for experiments in which human factors are involved. Cognitive load has not been considered in the workload model which is the focus of a future work. Later on in chapter 5, the results for each complexity factor as well as workload models are analyzed and discussed for each sector separately. Based on the airspace complexity results, areas where traffic situation had become complex were identified and the controller’s response to different situations are discussed. For each complexity factor as well as workload, the results for three different scenarios featuring different automation levels for two en-route and terminal sectors are compared. At last in chapter 6, the main ideas are discussed, thesis conclusions are presented and possible future work is suggested.
8

Technical Verification and Validation of TIS-B using VDL Mode 4

Fredriksson, Daniel, Schweitz, Anders January 2004 (has links)
<p>This report is a technical verification and validation of Traffic Information Service Broadcast (TIS-B) using the data link VDL Mode 4. </p><p>The main objective of the report is to examine the usefulness of TIS-B considering the results from tests performed in the Stockholm Terminal Area and for the Advanced Surface Movement Guidance and Control System (A-SMGCS) at Arlanda airport. The results are compared with the requirements that have been set by the standardisation organisations ICAO, RTCA, Eurocontrol and Eurocae. TIS-B is however such a new concept, so most of the operational requirements have not yet been defined.</p><p>The process for performing the evaluation of TIS-B involves three stages: </p><p>· Study the requirements on TIS-B, ADS-B, radar and A-SMGCS. </p><p>· Verify TIS-B by performing tests at Arlanda airport. </p><p>· Validate the test results through analysis. </p><p>A theoretical study of slot allocation optimisation is performed to decide how the slot allocation is to be implemented. </p><p>The report includes a Functional Hazard Analysis (FHA). The FHA is done to see if the applications for TIS-B are ready for implementation or if more hazard preventing actions has to be taken, before any operational actions can be performed. </p><p>The report also involves a theoretical introduction to Air Traffic Management (ATM), Surveillance techniques and TIS-B. </p><p>All parts included in the report results in conclusions and recommendations regarding the TIS-B service.</p>
9

Technical Verification and Validation of ADS-B/VDL Mode 4 for En-route Airspace and Major Terminal Areas

Granberg, Petter, Li, Roger January 2002 (has links)
This report is a technical verification and validation of Automatic Dependent Surveillance – Broadcast (ADS-B) over Very High Frequency Data Link Mode 4 (VDL Mode 4) for the use as surveillance in terminal areas and en-route airspace in non-radar areas. The main objective is to verify that ADS-B/VDL Mode 4 fulfils the technical requirements for an implementation at Kiruna airport, Sweden. Comparison has been made to the current requirements for Secondary Surveillance Radar (SSR). The work in this report has been conducted in three phases: preliminary study, tests and verification and validation. During the preliminary study documents primarily from EUROCONTROL and ICAO were used to find out which requirements that were applicable. The next part consisted of both practical tests and theoretical verification of the VDL Mode 4 performance. Finally the results from the tests were validated and put together in this report. Main conclusion from this report is that ADS-B/VDL Mode 4 fulfils the corresponding SSR requirements. Therefore ADS-B/VDL Mode 4 should be able to serve as primary mean for surveillance in non-radar areas. The results from this report will constitute a part of the technical subset of future safety case for ADS-B in non-radar areas. The complete safety case will be used to authorize ADS-B/VDL Mode 4 in non-radar airspace, both in Sweden and internationally.
10

Technical Verification and Validation of ADS-B/VDL Mode 4 for A-SMGCS / Teknisk verifiering och validering av ADS-B/VDL Mode 4 för A-SMGCS

Eriksson, Matts, Lundmark, Jonas January 2002 (has links)
This report is a technical verification and validation of ADS-B (Automatic Dependent Surveillance – Broadcast) over VDL Mode 4 (Very High Frequency Data Link Mode 4) for the use in the surveillance element of an A-SMGCS (Advanced Surface Movement Guidance and Control System). The main objective of this report is to examine if ADS-B/VDL Mode 4 fulfils the technical requirements for an implementation at Arlanda airport, Stockholm Sweden. The report also includes a FMECA (Failure Mode, Effects and Criticality Analysis), a theoretical background and methods for monitoring. The process of making this report can be divided into three phases: 1. Preliminary Study. In this phase the requirements were examined and structured. 2. Verification. In this phase the system performance has been verified both theoretically and by several tests at Arlanda Airport. Simulation results have also been used. 3. Validation and documentation. The tests and verifications that were performed in phase 2 were validated in the third phase of the project. The final project document was also written in this phase. The main conclusion from this analysis is that ADS-B/VDL Mode 4 is well suited for surveillance. ADS-B/VDL Mode 4 has the possibility to fulfil all considered requirements, apart from detecting all obstacles. But if all the requirements are going to be fulfilled depends both on the implementation and the operational environment. The results from this verification and validation should be used as the technical subset in a future safety case, both in Sweden and internationally.

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