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Spínací mechanismus ve výkonovém jističi / Switching mechanism in the molded case circuit breakerMejzlík, Tomáš January 2014 (has links)
This paper deals with mechanical switch in circuit breaker designed for low voltage. The goal of this thesis was to analyze switching mechanism both theoretically and practically. Theoretical analysis consist of study different types of switching mechanism and analytical calculations of acceleration speed and trajectory. Practical analysis has been made taking a video with high speed camera of real switching mechanism of a circuit breaker and software analysis of the data. The next part of a thesis is about 3D modeling, animating and simulating of a switchgear switching mechanism.
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Vliv cílené modifikace topografie na elastohydrodynamické mazací filmy / Effect of surface texturing on elastohydrodynamic filmsPuchner, Jiří January 2008 (has links)
Diploma thesis describes analysis of influence of surface texturing on non-conformal rubbing surfaces. High speed camera was used to observe the effect of micro-dents of various depths on film thickness under pure rolling and rolling/sliding conditions. It can be concluded from the obtained results that micro-texture of suitable sizes can results in film thickness increase without lubrication film breakdown.
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Non-invasive seedingless measurements of the flame transfer function using high-speed camerabased laser vibrometryGürtler, Johannes, Greiffenhagen, Felix, Woisetschläger, Jakob, Haufe, Daniel, Czarske, Jürgen 09 August 2019 (has links)
The characterization of modern jet engines or stationary gas turbines running with lean combustion by means of swirl-stabilized ames necessitates seedingless optical field measurements of the ame transfer function, i.e. the ratio of the uctuating heat release rate inside the ame volume, the instationary ow velocity at the combustor outlet and the time average of both quantities. For this reason, a high-speed camera-based laser interferometric vibrometer is proposed for spatio-temporally resolved measurements of the ame transfer function inside a swirl-stabilized technically premixed ame. Each pixel provides line-of-sight measurements of the heat release rate due to the linear coupling to uctuations of the refractive index along the laser beam, which are based on density uctuations inside the ame volume. Additionally, field measurements of the instationary ow velocity are possible due to correlation of simultaneously measured pixel signals and the known distance between the measurement positions. Thus, the new system enables the spatially resolved detection of the ame transfer function and instationary ow behavior with a single measurement for the first time. The presented setup offers single pixel resolution with measurement rates up to 40 kHz at an maximum image resolution of 256 px x 128 px. Based on a comparison with reference measurements using a standard pointwise laser interferometric vibrometer, the new system is validated and a discussion of the measurement uncertainty is presented. Finally, the measurement of refractive index uctuations inside a ame volume is demonstrated.
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High-Frame-Rate Oil Film InterferometryWhite, Jonathan Charles 01 May 2011 (has links) (PDF)
High-Frame-Rate Oil Film Interferometry
Jonathan Charles White
This thesis presents the design and implementation of a high-frame-rate oil film interferometry technique (HOFI) used to directly measure skin friction in time dependent flows. Experiments were performed to determine the ability of a high-speed camera to capture oil film interferometry images. HOFI was found to be able to capture these interferometry images at frequencies up to 105 Hz. Steady laminar and turbulent flows were tested. Transient flows tested consisted of a wind tunnel ramping up in velocity and a laminar boundary layer which was intermittently tripped to turbulence by puffing air out of a pressure tap. Flow speeds ranged from 0 to 108 ft/sec and 10 and 50 cSt Dow Corning 200 dimethylpolysiloxane silicone oil was used. The skin friction was determined from the rate of change of the height of the oil film using lubrication theory. The height of the oil film was determined from the high speed camera interferogram images using a MATLAB script which determined fringe spacing by fitting a four-parameter sine wave to the intensity levels in each image. The MATLAB script was able to determine the height of the oil film for thousands of interferogram images in only a few minutes with sub-pixel error in fringe spacing. The skin friction was calculated using the oil film height history allowing for the direct measurement of skin friction in time dependent flows.
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Metodologia teórica e experimental para determinação das características do ressalto hidráulico clássico / Theoretical and experimental methodology for determining the characteristics of classical hydraulic jumpNóbrega, Juliana Dorn 10 June 2014 (has links)
Embora o ressalto hidráulico seja um assunto já muito estudado, é igualmente um assunto de grande interesse, acerca do qual ainda existem diversos questionamentos a respeito de suas características. Por essa razão, buscou-se neste projeto o desenvolvimento de estudos experimentais e a proposição de um modelo teórico. Os trabalhos experimentais foram desenvolvidos com o uso de um sensor ultrassônico, para aquisição de dados instantâneos da superfície livre, sendo estudados ressaltos com número de Froude na seção supercrítica entre 1,94 e 5,26 e duas condições de controle a montante: comporta plana e vertedor de soleira espessa. As seguintes variáveis foram avaliadas a partir dos experimentos: comprimento do rolo, comprimento do ressalto, intensidade turbulenta vertical, perfil da superfície livre e frequências dos sinais de saída do sensor. Os perfis da superfície livre, considerando-se separadamente os dados de comporta e vertedor, foram ajustados a partir de uma equação heurística e as frequências características foram comparadas com os comprimentos característicos do ressalto. Além disso, foram efetuados registros fotográficos do escoamento com uma câmera de alta velocidade e luz laser para uma condição experimental (com baixo número de Froude supercrítico), sendo a superfície livre detectada por meio de técnicas usuais de processamento de imagens. O perfil médio obtido com o sensor foi semelhante ao perfil das imagens. Em relação ao modelo teórico proposto, este foi desenvolvido a partir de dois volumes de controle (VC) fixos, sendo obtidas duas equações para a relação entre o comprimento do rolo e a altura supercrítica. Verificou-se uma variação de quarenta porcento entre os valores previstos com as equações e os dados experimentais, em função da própria divergência dos dados de comprimento do rolo indicados pelos autores. De forma geral, o estudo mostrou-se relevante por possibilitar a avaliação da estrutura externa do ressalto hidráulico por meio de diferentes abordagens metodológicas. / Althought hydraulic jump has been studied for a long time, it is equally a theme of large interest, which many aspects related to its characteristics remain unanswered. Therefore, the development of experimental studies and the proposal of a theoretical model was sought in this project. The experimental works were carried out using an ultrassonic sensor, in order to acquire instantaneous data of the free surface, being studied hydraulic jumps with inflow Froude number ranging between 1.94 and 5.26 and two upstream control structures: plane gate and broad-crested weir. The following variables were evaluated: roller length, hydraulic jump length, vertical turbulent intensity, free surface profile, frequencies of the output data sensor. The free surface profiles, considering individually the plane gate and broad-crested weir, were adjested using a heuristic equation and characteristic frequencies were compared to the characteristic jump lengths. Furthermore, the flow was photographed using a high speed camera and a laser light for one experimental condition (for low inflow Froude number). The free surface in images were detected trought usual image processing techniques. The mean profile obtained from the sensor was very similar to the images profile. Regarding the theoretical model, it was developed considering two fixed control volumes (VC), obtaining two equations for the roller length and supercritical depth ratio. A variation of forty percent was observed between the predicted and experimental values, due to the own divergence among the roller length data suggested by the authors. Overall, the study was relevant, because it allowed the evaluation of the external structure of hydraulic jumps by means of different methodological approaches.
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Mesure de vibrations par vision 3D / 3D vision vibration measurementDurand-Texte, Thomas 11 January 2019 (has links)
La finalité de cette thèse est d’étudier la pertinence et les limites des méthodes de vision 3D couplées à une caméra ultra-rapide pour la mesure de champs vibratoires, sans contact et de manière synchrone, dans le domaine des fréquences associées à la vibro-acoustique. Un premier montage pseudo stéréoscopique, issu de la robotique, mobilisant un jeu de quatre miroirs afin de générer deux vues virtuelles à partir d’une seule caméra réelle, a été testé sur une plaque et un haut-parleur. Les résultats, validés par comparaison avec ceux obtenus avec un vibromètre laser, attestent de la pertinence de l’approche en dépit des contraintes liées aux éléments optiques. Dans une logique de simplification, trois autres montages ont alors été proposés et testés, permettant de concevoir deux techniques de mesure de vibration plein champ et une méthode itérative de rectification d’images (IRIs), adaptées au contexte. La méthode sans miroir utilise une ligne mathématique pour la triangulation et est fondamentalement adaptée à la mesure de vibrations mono-axiales d'objets globalement plans, affichant des déplacements non-répétables selon la normale de la surface ou selon un axe connu. La méthode à caméras asynchrones, quant à elle, utilise une caméra ultra-rapide et une caméra rapide, et permet la mesure de vibrations multi-axiales de phénomènes vibratoires 3D. Les résultats obtenus sur le capot d’une voiture et sur un haut-parleur attestent de son potentiel pour la caractérisation de panneaux ou le test qualité de fin de chaine d’assemblage de haut-parleurs par exemple. En conclusion, les trois protocoles de mesure et les résultats associés sont comparés afin de cibler leurs potentialités et limites respectives dans le contexte de la mesure de vibrations. / The objective of this Ph.D is to study the relevance and limits of 3D vision methods coupled to high-speed cameras and applied to non-contact synchronous vibration measurement, in the vibro-acoustic range of frequencies. A first pseudo stereoscopic set-up, taken from robotics, using a four-mirror adapter in order to generate two virtual viewpoints from a single real camera, has been tested on a plate and a loudspeaker. The results, validated by comparison with those obtained with a laser vibrometre, prove the relevance of the approach, despite some constraints related to the optical elements. In a logic of simplification, three other set-ups have then been proposed and tested, allowing designing two full-field vibration measurement techniques and a method for the Iterative Rectification of Images (IRIs), adapted to the context. The no-mirror method uses a mathematical line to triangulate positions and is basically suited to measure the single-axis vibrations of globally plane objects, displaying non-repeatable displacements along the normal of the surface or along a known axis. The asynchronous cameras technique requires a high-speed and an industrial camera used simultaneously to measure the multi-axis displacements of 3D vibratory phenomena. The results obtained on a car bonnet and a loudspeaker prove its potential to characterise large panels or to carry out end-of-line testing of loud-speakers for example. In conclusion, the three measurement protocols and the associated results are compared in order to assess their respective potentialities and limits in the context of vibration measurement.
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Aktivering av trafiksäkerhetskameror : En studie av kameraaktiveringens effekter på fordonshastigheter i Sverige / Activation of speed cameras : A study of the effects of camera activation on vehicle speeds in SwedenLundström, Josefine, Ruotsalainen, Juoni January 2008 (has links)
During 2006 an estimated number of 150 persons are supposed to have been killed in road accidents caused by speed limit violations. Through Automatic traffic security control (ATK) the Swedish road administration (Vägverket) is working towards lowering the number of speed related accidents. By placing the speed cameras on roads they've managed to lower the average speed at those places. The enlargement of the number of speed cameras is based upon knowledge about for example how high the risk is for speed related accidents on the roads. The speed cameras always measure the speed in which every vehicle passes, but aren't constantly activated to register speed violations. Our purpose with this essay is consequently to explore possible relations between the activation of the speed cameras and the speed itself on the roads.We studied the average speed and the number of speed violations during 12 weeks evenly distributed in 2007. To see if the results would differ, we used two different response variables in the analysis. Multiple linear regression was used to analyse the average speed, while Poisson regression was used in the analysis of the number of speed violations. An activated camera proved to cause a lowered average speed and fewer speed violations in three regions (Skåne, Mälardalen, Norr).To study the effect of maximized camera activation, an experiment in the region of Mälardalen was performed in the beginning of 2008. The result showed that maximized camera activation didn't decelerate the average speed, in stead the region's own activation policy seems to be more important for a lowered average speed. When the traffic flow rises the average speed decelerates while the number of speed violations also rises. During the study of commuter traffic we could see that the average speed is lower and there is fewer speed violations on commuter roads compared to normal traffic roads. / Under 2006 beräknas 150 personer ha omkommit i vägtrafikolyckor på grund av överskridna hastighetsgränser. Vägverket arbetar för att sänka dessa siffror bland annat genom att använda sig av Automatisk trafiksäkerhetskontroll (ATK). Genom att placera trafiksäkerhetskameror på sträckor har medelhastigheten på dessa sänkts. Trafiksäkerhetskamerorna mäter alltid hastigheten hos varje passerande fordon, men är inte konstant aktiverade för att registrera hastighetsöverträdelser. Nu vill man optimera kameraaktiveringen för att minska antalet ärenden utan att hanteringskapaciteten överskrids. Vårt syfte med uppsatsen är därför att undersöka möjliga samband mellan aktivering av trafiksäkerhetskameror och själva hastigheten på vägarna.Medelhastigheten och antalet överträdelser studerades under tolv veckor jämnt fördelade över år 2007. Analyserna gjordes med två olika responsvariabler för att se om resultaten skilde sig åt. Vi använde oss av multipel linjär regression för att analysera medelhastigheten, medan Poissonregression användes för antalet överträdelser. Det visade sig att en aktiv kamera gav upphov till sänkta medelhastigheter och färre hastighetsöverträdelser i tre regioner (Skåne, Mälardalen, Norr).För att studera effekten av maximal kameraaktivering utfördes ett experiment i region Mälardalen under början av 2008. Det visade sig att en maximal aktivering inte gav en sänkning av genomsnittshastigheterna, istället verkar regionens egen aktiverings-strategi ha större betydelse för sänkta genomsnittshastigheter.När fordonsflödet på alla sträckor ökar så minskar medelhastigheten medan antalet överträdelser ökar. För pendeltrafiksträckor är medelhastigheten lägre och det sker färre hastighetsöverträdelser än på normaltrafiksträckor.
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Wirksamkeit von Maßnahmen zur Verbesserung der Verkehrssicherheit auf einbahnigen LandstraßenJährig, Thomas 31 July 2012 (has links) (PDF)
An einbahnige Außerortsstraßen (Landstraßen) werden sehr hohe Anforderungen gestellt. Einerseits sollen sie eine hohe Verkehrssicherheit aufweisen und andererseits gemäß ihrer Verkehrsbedeutung eine angemessene Verkehrsqualität und Leistungsfähigkeit bereitstellen. Im Landstraßennetz liegt die Erfüllung dieser Anforderungen jedoch vielerorts deutlich unter den Erwartungen.
Unfälle auf Landstraßen sind im Vergleich zu Autobahnen oder Innerortsstraßen durch eine besonders hohe Schwere gekennzeichnet. Sehr hohe und oft an den Streckenverlauf nicht hinreichend angepasste Geschwindigkeiten, Fehleinschätzungen von Geschwindigkeiten bzw. Geschwindigkeitsdifferenzen entgegenkommender und vorausfahrender Fahrzeuge sowie die im Standardfall für Überholvorgänge notwendige Nutzung des Gegenfahrstreifens sind die Hauptursachen für die schweren Unfälle auf Landstraßen.
Das Ziel der vorliegenden Arbeit war die Untersuchung der Wirksamkeit von kurz- und mittelfristig umsetzbaren Maßnahmen zur Verbesserung der Verkehrssicherheit auf unfallauffälligen einbahnigen Außerortsstraßen. Die Untersuchungen dafür erfolgten im Rahmen des Großversuches „Außerortsstraßensicherheit“ (AOSI). Im Ergebnis sollten Einsatzempfehlungen für die Planungs- und Entwurfspraxis und für zukünftige Regelwerke für den Landstraßenentwurf abgeleitet werden.
Für die Durchsetzung der zulässigen Höchstgeschwindigkeit wurden auf fünf ausgewählten Bundesstraßenabschnitten linienhaft angeordnete ortsfeste Geschwindigkeitsüberwachungsanlagen (OGÜ) eingerichtet. Auf fünf weiteren Bundesstraßenabschnitten wurde das Überholen nur auf den dafür angelegten Überholfahrstreifen (ÜFS) zugelassen. Auf den verbliebenen zweistreifigen Zwischenabschnitten wurden Überholverbote (ÜV) erlassen.
Nach dem von der AOSI-Projektgruppe vorgegebenen Messregime und den so ermittelten Rohdaten wurde eine eigene Untersuchungsmethodik entwickelt und die vorliegende Datenlage entsprechend aufbereitet. Darauf gestützt erfolgte die Auswertung und Interpretation sowie die Ableitung der Empfehlungen.
Durch die linienhafte ortsfeste Geschwindigkeitsüberwachung konnte eine deutliche Verbesserung der Verkehrssicherheit erzielt werden und damit das Unfallrisiko auf den Untersuchungsstrecken teils erheblich reduziert werden. Es konnte gezeigt werden, dass die Grundlage dieser Entwicklung die Durchsetzung der zulässigen Höchstgeschwindigkeit war, die vor der Überwachung um bis zu 20 km/h überschritten wurde.
Diese Entwicklung war nicht nur auf eine Reduktion der Fahrunfälle zurückzuführen. Durch die Verringerung der Geschwindigkeitsunterschiede zwischen den Fahrzeugen sank der Überholdruck, was besonders auf den Untersuchungsstrecken mit einer gestreckten Linienführung auch einen Rückgang der Unfälle im Längsverkehr bewirkte.
Nach der Eingewöhnungszeit stellte sich das erwartete Fahrverhalten entlang der Untersuchungsstrecken ein, das nicht mehr durch deutliche Verzögerungs- und Beschleunigungsvorgänge im Bereich der Geschwindigkeitsüberwachungsanlagen geprägt war. Förderlich für diese Entwicklung war trotz anfänglicher Skepsis die breite Akzeptanz der Kraftfahrer zu den OGÜ-Anlagen als sinnvolle Maßnahme zur Verbesserung der Verkehrssicherheit. Erreicht wurde dies mit einer verständlichen Öffentlichkeitsarbeit zu den Hintergründen und Zielen der Maßnahme.
Die Kombination von abschnittsweisen sicheren Überholmöglichkeiten (ÜFS) und Überholverboten in den einbahnig zweistreifigen Zwischenabschnitten (ÜV) ist eine geeignete, mittelfristig umsetzbare Maßnahme zur Verbesserung der Verkehrssicherheit. Die Wirkung der Maßnahme ist vorrangig auf die Unfälle im Längsverkehr gerichtet und sollte daher auf Strecken erwogen werden, bei denen das Unfallgeschehen vor allem durch einen hohen Anteil von Überholunfällen gekennzeichnet ist. Der Vorteil liegt im Abbau des Überholdrucks unabhängig von den verfügbaren Zeitlücken im Gegenverkehr.
Dafür haben sich auch kurze Überholfahrstreifen (l ≥ 600 m) bewährt, die im Bestandsnetz eher realisierbar sind. Die untersuchte Maßnahmenkombination aus einem sicheren Überholangebot und einem Überholverbot in den einbahnig zweistreifigen Abschnitten erfährt zudem eine hohe Akzeptanz bei den Verkehrsteilnehmern.
Durch die Ergebnisse dieser Arbeit liegen Empfehlungen vor, um die Verkehrssicherheit auf unfallauffälligen Abschnitten einbahniger Außerortsstraßen kurz- und mittelfristig zu verbessern. Dies gilt vor allem dann, wenn das Unfallgeschehen vorrangig auf eine zu hohe und unangepasste Geschwindigkeit oder auf Fehler bei Überholvorgängen zurückzuführen ist. Die Ergebnisse liefern darüber hinaus belastbare Grundlagen für das neue Regelwerk für den Landstraßenentwurf.
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Dynamics of the free surface of stratified two-phase flows in channels with rectangular cross-sectionsVallée, Christophe 24 April 2012 (has links) (PDF)
Stratified two-phase flows were investigated at different test facilities with horizontal test sections in order to provide an experimental database for the development and validation of computational fluid dynamics (CFD) codes. These channels were designed with rectangular cross-sections to enable optimal observation conditions for the application of optical measurement techniques. Consequently, the local flow structure was visualised with a high-speed video camera, delivering data with high-resolution in space and time as needed for CFD code validation.
Generic investigations were performed at atmospheric pressure and room temperature in two air/water channels made of acrylic glass. Divers preliminary experiments were conducted with various measuring systems in a test section mounted between two separators. The second test facility, the Horizontal Air/Water Channel (HAWAC), is dedicated to co-current flow investigations. The hydraulic jump as the quasi-stationary discontinuous transition between super- and subcritical flow was studied in this closed channel. Moreover, the instable wave growth leading to slug flow was investigated from the test section inlet. For quantitative analysis of the optical measurements, an algorithm was developed to recognise the stratified interface in the camera frames, allowing statistical treatments for comparison with CFD calculation results.
The third test apparatus was installed in the pressure chamber of the TOPFLOW test facility in order to be operated at reactor typical conditions under pressure equilibrium with the vessel atmosphere. The test section representing a flat model of the hot leg of the German Konvoi pressurised water reactor (PWR) scaled at 1:3 is equipped with large glass side walls in the region of the elbow and of the steam generator inlet chamber to allow visual observations. The experiments were conducted with air and water at room temperature and maximum pressures of 3 bar as well as with steam and water at boundary conditions of up to 50 bar and 264°C. Four types of experiments were performed, including generic test cases as well as transient validation cases of typical nuclear reactor safety issues. As an example, the co-current flow experiments simulate the two-phase natural circulation in the primary circuit of a PWR. The probability distribution of the water level measured in the reactor pressure vessel simulator was used to characterise the flow in the hot leg. Moreover, the flooding behaviour in this conduit was investigated with dedicated counter-current flow limitation experiments. A comparison of the flooding characteristics with similar experimental data and correlations available in the literature shows that the channel height is the characteristic length to be used in the Wallis parameter for channels with rectangular cross-sections. Furthermore, for the analysis of steam/water experiments, condensation effects had to be taken into account. Finally, the experimental results confirm that the Wallis similarity is appropriate to scale flooding in the hot leg of a PWR over a large range of pressure and temperature conditions.
Not least, different examples of comparison between experiment and simulation demonstrate the possibilities offered by the data to support the development and validation of CFD codes. Besides the comparison of qualitative aspects, it is shown exemplarily how to treat the CFD results in order to enable quantitative comparisons with the experiments.
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Aktivering av trafiksäkerhetskameror : En studie av kameraaktiveringens effekter på fordonshastigheter i Sverige / Activation of speed cameras : A study of the effects of camera activation on vehicle speeds in SwedenLundström, Josefine, Ruotsalainen, Juoni January 2008 (has links)
<p>During 2006 an estimated number of 150 persons are supposed to have been killed in road accidents caused by speed limit violations. Through Automatic traffic security control (ATK) the Swedish road administration (Vägverket) is working towards lowering the number of speed related accidents. By placing the speed cameras on roads they've managed to lower the average speed at those places. The enlargement of the number of speed cameras is based upon knowledge about for example how high the risk is for speed related accidents on the roads. The speed cameras always measure the speed in which every vehicle passes, but aren't constantly activated to register speed violations. Our purpose with this essay is consequently to explore possible relations between the activation of the speed cameras and the speed itself on the roads.We studied the average speed and the number of speed violations during 12 weeks evenly distributed in 2007. To see if the results would differ, we used two different response variables in the analysis. Multiple linear regression was used to analyse the average speed, while Poisson regression was used in the analysis of the number of speed violations. An activated camera proved to cause a lowered average speed and fewer speed violations in three regions (Skåne, Mälardalen, Norr).To study the effect of maximized camera activation, an experiment in the region of Mälardalen was performed in the beginning of 2008. The result showed that maximized camera activation didn't decelerate the average speed, in stead the region's own activation policy seems to be more important for a lowered average speed. When the traffic flow rises the average speed decelerates while the number of speed violations also rises. During the study of commuter traffic we could see that the average speed is lower and there is fewer speed violations on commuter roads compared to normal traffic roads.</p> / <p>Under 2006 beräknas 150 personer ha omkommit i vägtrafikolyckor på grund av överskridna hastighetsgränser. Vägverket arbetar för att sänka dessa siffror bland annat genom att använda sig av Automatisk trafiksäkerhetskontroll (ATK). Genom att placera trafiksäkerhetskameror på sträckor har medelhastigheten på dessa sänkts. Trafiksäkerhetskamerorna mäter alltid hastigheten hos varje passerande fordon, men är inte konstant aktiverade för att registrera hastighetsöverträdelser. Nu vill man optimera kameraaktiveringen för att minska antalet ärenden utan att hanteringskapaciteten överskrids. Vårt syfte med uppsatsen är därför att undersöka möjliga samband mellan aktivering av trafiksäkerhetskameror och själva hastigheten på vägarna.Medelhastigheten och antalet överträdelser studerades under tolv veckor jämnt fördelade över år 2007. Analyserna gjordes med två olika responsvariabler för att se om resultaten skilde sig åt. Vi använde oss av multipel linjär regression för att analysera medelhastigheten, medan Poissonregression användes för antalet överträdelser. Det visade sig att en aktiv kamera gav upphov till sänkta medelhastigheter och färre hastighetsöverträdelser i tre regioner (Skåne, Mälardalen, Norr).För att studera effekten av maximal kameraaktivering utfördes ett experiment i region Mälardalen under början av 2008. Det visade sig att en maximal aktivering inte gav en sänkning av genomsnittshastigheterna, istället verkar regionens egen aktiverings-strategi ha större betydelse för sänkta genomsnittshastigheter.När fordonsflödet på alla sträckor ökar så minskar medelhastigheten medan antalet överträdelser ökar. För pendeltrafiksträckor är medelhastigheten lägre och det sker färre hastighetsöverträdelser än på normaltrafiksträckor.</p>
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