Yes / Inter-arm differences (IAD) ≥10mmHg in systolic blood pressure (BP) are associated with greater incidence of cardiovascular disease. The effect of ethnicity and the white coat effect (WCE) on significant systolic inter-arm differences (ssIADs) are not well understood. Methods: Differences in BP by ethnicity for different methods of BP measurement were examined in 770 people (300 White British, 241 South Asian, 229 African-Caribbean). Repeated clinic measurements were obtained simultaneously in the right and left arm using two BP-Tru monitors and comparisons made between the first reading, mean of second and third and mean of second to sixth readings for patients with, and without known hypertension. All patients had ambulatory monitoring (ABPM). WCE was defined as systolic Clinic BP ≥10mmHg higher than daytime ABPM. Results: No significant differences were seen in the prevalence of ssIAD between ethnicities whichever combinations of BP measurement were used and regardless of hypertensive status. ssIADs fell between the 1st measurement (161, 22%), 2nd/3rd (113, 16%) and 2nd-6th (78, 11%) (1st vs 2nd/3rd and 2nd-6th, p<0.001). Hypertensives with a WCE were more likely to have ssIADs on 1st, (OR 1.73 (95% CI 1.04-2.86), 2nd/3rd, (OR 3.05 (1.68-5.53) and 2nd-6th measurements, (OR 2.58 (1.22-5.44). Non-hypertensive participants with a WCE were more likely to have a ssIAD on their first measurement (OR 3.82 (1.77 -8.25) only. Conclusion: ssIAD prevalence does not vary with ethnicity regardless of hypertensive status but is affected by the number of readings, suggesting the influence of WCE. Multiple readings should be used to confirm ssIADs. / This report presents independent research funded by the National Institute for Health Research (NIHR).

Die 3D Particle Tracking Velocimetry (3D PTV) ist eine Methode zur bildbasierten Bestimmung von Geschwindigkeitsfeldern in Gas- oder Flüssigkeitsströmungen. Dazu wird die Strömung mit Partikeln markiert und durch ein Mehrkamerasystem beobachtet. Das Ergebnis der Datenauswertung sind 3D Trajektorien einer großen Anzahl von Partikeln, die zur statistischen Analyse der Strömung genutzt werden können. In der vorliegenden Arbeit werden verschiedene neu entwickelte Modelle gezeigt, die das Einsatzspektrum vergrößern und die Leistungsfähigkeit der 3D PTV erhöhen. Wesentliche Neuerungen sind der Einsatz eines Spiegelsystems zur Generierung eines virtuellen Kamerasystems, die Modellierung von komplex parametrisierten Trennflächen der Mehrmedienphotogrammetrie, eine wahrscheinlichkeitsbasierte Trackingmethode sowie eine neuartige Methode zur tomographischen Rekonstruktion von Rastervolumendaten. Die neuen Modelle sind an drei realen Experimentieranlagen und mit synthetischen Daten getestet worden. Durch den Einsatz eines Strahlteilers vor dem Objektiv einer einzelnen Kamera und vier Umlenkspiegeln, positioniert im weiteren Strahlengang, werden vier virtuelle Kameras generiert. Diese Methode zeichnet sich vor allem durch die Wirtschaftlichkeit als auch durch die nicht notwendige Synchronisation aus. Vor allem für die Anwendung im Hochgeschwindigkeitsbereich sind diese beiden Faktoren entscheidend. Bei der Beobachtung von Phänomenen in Wasser kommt es an den Trennflächen verschiedener Medien zur optischen Brechung. Diese muss für die weitere Auswertung zwingend modelliert werden. Für komplexe Trennflächen sind einfache Ansätze über zusätzliche Korrekturterme nicht praktikabel. Der entwickelte Ansatz basiert auf der mehrfachen Brechung jedes einzelnen Bildstrahls. Dazu müssen die Trennflächenparameter und die Kameraorientierungen im selben Koordinatensystem bekannt sein. Zumeist wird die Mehrbildzuordnung von Partikeln durch die Verwendung von Kernlinien realisiert. Auf Grund von instabilen Kameraorientierungen oder bei einer sehr hohen Partikeldichte sind diese geometrischen Eigenschaften nicht mehr ausreichend, um die Mehrbildzuordnung zu lösen. Unter der Ausnutzung weiterer geometrischer, radiometrischer und physikalischer Eigenschaften kann die Bestimmung der 3D Trajektorien dennoch durchgeführt werden. Dabei werden durch die Analyse verschiedener Merkmale diejenigen ausgewählt, welche sich für die spatio-temporale Zuordnung eignen. Die 3D PTV beruht auf der Diskretisierung der Partikelabbildungen im Bildraum und der anschließenden Objektkoordinatenbestimmung. Eine rasterbasierte Betrachtungsweise stellt die tomographische Rekonstruktion des Volumens dar. Hierbei wird die Intensitätsverteilung wird im Volumen rekonstruiert. Die Bewegungsinformationen werden im Anschluss aus den Veränderungen aufeinander folgender 3D-Bilder bestimmt. Durch dieses Verfahren können Strömungen mit einer höheren Partikeldichte im Volumen analysiert werden. Das entwickelte Verfahren basiert auf der schichtweisen Entzerrung und Zusammensetzung der Kamerabilder. Die entwickelten Modelle und Ansätze sind an verschiedenen Versuchsanlagen erprobt worden. Diese unterschieden sich stark in der Größe (0,5 dm³ – 20 dm³ – 130 m³) und den vorherrschenden Strömungsgeschwindigkeiten (0,3 m/s – 7 m/s – 0,5 m/s). / 3D Particle Tracking Velocimetry (3D PTV) is an image based method for flow field determination. It is based on seeding a flow with tracer particles and recording the flow with a multi camera system. The results are 3D trajectories of a large number of particles for a statistical analysis of the flow. The thesis shows different novel models to increase the spectrum of applications and to optimize efficiency of 3D PTV. Central aspects are the use of the mirror system to generate a virtual multi camera system, the modelling of complex interfaces of multimedia photogrammetry, a probability based tracking method and a novel method for tomographic reconstruction of volume raster data. The improved models are tested in three real testing facilities and with synthetic data. Using a beam splitter in front of the camera lens and deflecting mirrors arranged in the optical path, a four headed virtual camera system can be generated. This method is characterised by its economic efficiency and by the fact that a synchronisation is not necessary. These facts are important especially when using high speed cameras. When observing phenomena in water, there will be refraction at the different interfaces. This has to be taken into account and modelled for each application. Approaches which use correction terms are not suitable to handle complex optical interfaces. The developed approach is based on a multiple refraction ray tracing with known interface parameters and camera orientations. Mostly the multi image matching of particles is performed using epipolar geometry. Caused by the not stable camera orientation or a very high particle density this geometric properties are not sufficient to solve the ambiguities. Using further geometrical radiometrical and physical properties of particles, the determination of the 3D trajectories can be performed. After the analysis of different properties those of them are chosen which are suitable for spatio-temporal matching. 3D PTV bases on the discretisation of particle images in image space and the following object coordinate determination. A raster based approach is the tomographic reconstruction of the volume. Here the light intensity distribution in the volume will be reconstructed. Afterwards the flow information is determined from the differences in successive 3D images. Using tomographic reconstruction techniques a higher particle density can be analysed. The developed approach bases on a slice by slice rectification of the camera images and on a following assembly of the volume. The developed models and approaches are tested at different testing facilities. These differ in size (0.5 dm³ – 20 dm³ – 130 m³) and flow velocities (0.3 m/s – 7 m/s – 0.5 m/s).

L'étude proposée porte sur l'adaptation d'une méthode de mesure optique à lamesure de la topologie d'objet de grandes dimensions et à une distance de travail proche. Laméthode optique utilisée est la projection de franges car elle permet l'étude de grands objets.Dans un premier temps, des essais expérimentaux ont été réalisés pour évaluer l'exactitudedu développement actuel ; ce dernier utilisant une analyse de franges s'appuyant sur lacombinaison d'une méthode quasi-hétérodyne utilisant une transformation de Fourier etd'une méthode de code gray.Après avoir quantifié les erreurs et déterminé leurs sources, le choix dudéveloppement d'une procédure d'étalonnage et de nouvelles équations associées à cetteprocédure se sont imposés. Le nouvel étalonnage est quant à lui basé sur une interpolationpolynomiale de points définissant un volume de grandes dimensions. Un objet étalon a étéspécialement conçu pour cette procédure de calibration. Pour évaluer l'erreur du à lacalibration, une étude systématique de cas de polynômes dont le plus haut degré varie de 1à 4 a été effectué. Cette approche a permis de déterminer le degré optimal du polynôme àutiliser. Dans le meilleur cas, l'estimation de l'erreur a permis d'évaluer la précision del'étalonnage à 1 mm sur un objet de 2 m évalué à une distance de 2 m.La méthode a été par la suite appliquée, dans un cadre industriel à l'étude deflotteurs et dans un cadre médical à l'étude du relief de la paroi abdominale. D'un point devue médical, cette méthode permet d'obtenir rapidement et facilement la morphologie ducorps humain. Elle permet aussi d'effectuer un meilleur suivi des pathologiesmorphologiques des patients. / The proposed study deals with the adaptation of an optical method to themeasurement of large objects at a low working distance. The optical method used is thefringe projection technique allowing the study of large objects. At first, experimental trials hasbeen used to evaluate the accuracy of the actual development combining the phase shiftingmethod using a Fourier transform and the gray code technique.When the errors have been quantified and their origins determined, the developmentof a calibration procedure and new associated equations have been chosen. The newcalibration is based on polynomial interpolation of points defining a volume of largedimensions. A tested object was designed specifically for this calibration procedure. Toestimate the calibration error, a systematic study of polynomials cases is performed. Thehighest degree of those cases varies from 1 to 4. This approach allows the determination theoptimal polynomial degree to be used. In the best case, the estimation of the error allows theevaluation of the calibration accuracy of about 1 mm for an object of 2 m large, measured ata distance of 2 m.The method has been subsequently applied, in an industrial setting, to the study offloats and in a medical setting to the study of the relief of the abdominal wall. From a medicalpoint of view, this method gives a rapid and easy access to the topology of human body. Itallows a better follow-up of the patient pathology.

The thesis provides a comparison of different portfolio models and tests their performance on the financial markets. Our analysis particularly focuses on comparison of the classical Markowitz modern portfolio theory and the downside risk models of the post-modern portfolio theory. In addition, we consider some alternative portfolio models ending with total eleven models that we test. If the performance of different portfolio models should be evaluated and compared correctly, we must use a measure that is unbiased to any portfolio theory. We suggest solving this issue via a new approach based on the utility theory and utility functions. We introduce the unbiased method for evaluation of the portfolio model performance using the expected utility efficient frontier. We use the asymmetric behavioural utility function to capture the behaviour of the real market investors. The Markowitz model is the leading market practice. We investigate whether there are any circumstances in which some other models might provide better performance than the Markowitz model. Our research is for three reasons unique. First, it provides a comprehensive comparison of broad classes of different portfolio models. Second, we focus on the developed markets in United States and Germany but also on the local emerging markets in Czech Republic and Poland. These local markets have never been tested in such extent before. Third, the empirical testing is based on the broad data set from 2003 to 2012 which enable us to test how different portfolio model perform in different macroeconomic conditions.

Theoretical principles of the sixport measurement method are presented. Description of theoretical design and influence of its parameters on measurement precision follows. Simple sixport measurement system was made and its parameters are described. As the main thesis contribution there is described a new approach to method with more detectors in the system. Mean features are more valid sixports at one specific frequency and frequency bandwidth aviable up to 1 : 100 and more. Such a wideband measurement system was designed for the frequencies between 50 and 2680 MHz and its parameters are presented in the work.

<p>U disertaciji je prikazano teorijsko i praktično istraživanje koje se<br />odnosi na utvrđivanje potrebnih i dovoljnih uslova za merenje<br />harmonika u realnoj elektrodistributivnoj mreži. Cilj istraživanja<br />doktorske disertacije je formulisanje merne metode i na metodi<br />baziranom hardveru - po mogućnosti minimalne rezolucije<br />primenjenih A/D konvertora - praktično dvobitnih za merenje<br />harmonika u realnoj elektrodistributivnoj mreži. Jednostavan<br />hardver omogućuje jednostavna paralelna merenja, kao i mali broj<br />izvora sistematske greške merenja, što je vrlo primenljivo u<br />merenjima u realnoj distributivnoj mreži.Simulacionom analizom, a<br />potom i eksperimentom potvrđena je hipoteza istraživanja.</p> / <p>The dissertation shows the theoretical and practical research related to the<br />determination of necessary and sufficient conditions for the measurement of<br />harmonics in a real power grid. The aim of the PhD research is to formulate<br />method and hardware based on the measurement method - preferably with<br />minimal resolution of applied A/D converter - practically 2-bit, for harmonics<br />measurement in a real power grid. Simple hardware allows simple parallel<br />measurements, as well as a small number of systematic measurement error,<br />which is applicable for measurement in the real power grid. Simulation<br />analysis, followed by the experiment, confirmed the hypothesis of this<br />research.</p>

Die 3D Particle Tracking Velocimetry (3D PTV) ist eine Methode zur bildbasierten Bestimmung von Geschwindigkeitsfeldern in Gas- oder Flüssigkeitsströmungen. Dazu wird die Strömung mit Partikeln markiert und durch ein Mehrkamerasystem beobachtet. Das Ergebnis der Datenauswertung sind 3D Trajektorien einer großen Anzahl von Partikeln, die zur statistischen Analyse der Strömung genutzt werden können. In der vorliegenden Arbeit werden verschiedene neu entwickelte Modelle gezeigt, die das Einsatzspektrum vergrößern und die Leistungsfähigkeit der 3D PTV erhöhen. Wesentliche Neuerungen sind der Einsatz eines Spiegelsystems zur Generierung eines virtuellen Kamerasystems, die Modellierung von komplex parametrisierten Trennflächen der Mehrmedienphotogrammetrie, eine wahrscheinlichkeitsbasierte Trackingmethode sowie eine neuartige Methode zur tomographischen Rekonstruktion von Rastervolumendaten. Die neuen Modelle sind an drei realen Experimentieranlagen und mit synthetischen Daten getestet worden. Durch den Einsatz eines Strahlteilers vor dem Objektiv einer einzelnen Kamera und vier Umlenkspiegeln, positioniert im weiteren Strahlengang, werden vier virtuelle Kameras generiert. Diese Methode zeichnet sich vor allem durch die Wirtschaftlichkeit als auch durch die nicht notwendige Synchronisation aus. Vor allem für die Anwendung im Hochgeschwindigkeitsbereich sind diese beiden Faktoren entscheidend. Bei der Beobachtung von Phänomenen in Wasser kommt es an den Trennflächen verschiedener Medien zur optischen Brechung. Diese muss für die weitere Auswertung zwingend modelliert werden. Für komplexe Trennflächen sind einfache Ansätze über zusätzliche Korrekturterme nicht praktikabel. Der entwickelte Ansatz basiert auf der mehrfachen Brechung jedes einzelnen Bildstrahls. Dazu müssen die Trennflächenparameter und die Kameraorientierungen im selben Koordinatensystem bekannt sein. Zumeist wird die Mehrbildzuordnung von Partikeln durch die Verwendung von Kernlinien realisiert. Auf Grund von instabilen Kameraorientierungen oder bei einer sehr hohen Partikeldichte sind diese geometrischen Eigenschaften nicht mehr ausreichend, um die Mehrbildzuordnung zu lösen. Unter der Ausnutzung weiterer geometrischer, radiometrischer und physikalischer Eigenschaften kann die Bestimmung der 3D Trajektorien dennoch durchgeführt werden. Dabei werden durch die Analyse verschiedener Merkmale diejenigen ausgewählt, welche sich für die spatio-temporale Zuordnung eignen. Die 3D PTV beruht auf der Diskretisierung der Partikelabbildungen im Bildraum und der anschließenden Objektkoordinatenbestimmung. Eine rasterbasierte Betrachtungsweise stellt die tomographische Rekonstruktion des Volumens dar. Hierbei wird die Intensitätsverteilung wird im Volumen rekonstruiert. Die Bewegungsinformationen werden im Anschluss aus den Veränderungen aufeinander folgender 3D-Bilder bestimmt. Durch dieses Verfahren können Strömungen mit einer höheren Partikeldichte im Volumen analysiert werden. Das entwickelte Verfahren basiert auf der schichtweisen Entzerrung und Zusammensetzung der Kamerabilder. Die entwickelten Modelle und Ansätze sind an verschiedenen Versuchsanlagen erprobt worden. Diese unterschieden sich stark in der Größe (0,5 dm³ – 20 dm³ – 130 m³) und den vorherrschenden Strömungsgeschwindigkeiten (0,3 m/s – 7 m/s – 0,5 m/s). / 3D Particle Tracking Velocimetry (3D PTV) is an image based method for flow field determination. It is based on seeding a flow with tracer particles and recording the flow with a multi camera system. The results are 3D trajectories of a large number of particles for a statistical analysis of the flow. The thesis shows different novel models to increase the spectrum of applications and to optimize efficiency of 3D PTV. Central aspects are the use of the mirror system to generate a virtual multi camera system, the modelling of complex interfaces of multimedia photogrammetry, a probability based tracking method and a novel method for tomographic reconstruction of volume raster data. The improved models are tested in three real testing facilities and with synthetic data. Using a beam splitter in front of the camera lens and deflecting mirrors arranged in the optical path, a four headed virtual camera system can be generated. This method is characterised by its economic efficiency and by the fact that a synchronisation is not necessary. These facts are important especially when using high speed cameras. When observing phenomena in water, there will be refraction at the different interfaces. This has to be taken into account and modelled for each application. Approaches which use correction terms are not suitable to handle complex optical interfaces. The developed approach is based on a multiple refraction ray tracing with known interface parameters and camera orientations. Mostly the multi image matching of particles is performed using epipolar geometry. Caused by the not stable camera orientation or a very high particle density this geometric properties are not sufficient to solve the ambiguities. Using further geometrical radiometrical and physical properties of particles, the determination of the 3D trajectories can be performed. After the analysis of different properties those of them are chosen which are suitable for spatio-temporal matching. 3D PTV bases on the discretisation of particle images in image space and the following object coordinate determination. A raster based approach is the tomographic reconstruction of the volume. Here the light intensity distribution in the volume will be reconstructed. Afterwards the flow information is determined from the differences in successive 3D images. Using tomographic reconstruction techniques a higher particle density can be analysed. The developed approach bases on a slice by slice rectification of the camera images and on a following assembly of the volume. The developed models and approaches are tested at different testing facilities. These differ in size (0.5 dm³ – 20 dm³ – 130 m³) and flow velocities (0.3 m/s – 7 m/s – 0.5 m/s).

The doctoral thesis is concerned with Market Orientation (MO) and Customer Relationship Management (CRM). MO and CRM have been under permanent focus of both theoreticians and practitioners in recent years as they are considered to be important for long-term business success. Surprisingly, these two strategic concepts have been examined separately. What is missing is research that would systematically analyse the possible interdependence between MO and CRM. The main aim of the doctoral thesis is to evaluate the existence of interconnections between MO and CRM. This doctoral thesis has been prepared on the basis of secondary research, as well as primary research activities. Both qualitative and quantitative methods have been applied in order to obtain a more complex view on the topic. The main primary research of this thesis was conducted through a questionnaire survey among aerospace companies in the Czech Republic. The hypotheses were tested so as to support the partial objectives, as well. The findings constitute a valuable contribution to broaden the knowledge of MO and CRM. The doctoral thesis has revealed that MO and CRM are interconnected. A tool for CRM measurement was proposed, and the level of MO and CRM in the surveyed companies was determined. The barriers to the implementation of MO and CRM were identified, yet the actual application of these concepts in practice of companies has remained an issue. The conclusions and recommendations were formulated and the contributions to the theory, practice and education were highlighted. The findings offer the possibility of further expansion of research.

Vid utformning av väginfrastruktur borde trafikrelaterade utsläpp med ursprung från väg- och däckslitage samt halkbekämpning tas hänsyn till för att nå en verklig hållbar utveckling. Exempel på vägrelaterade utsläpp är aluminium, bly, koppar, kadmium, krom och zink. I Sverige sprids det omkring 200 000 - 230 000 ton salt per år på vägarna för att bekämpa halka under vinterhalvåret. Vattenlösliga föroreningar antas spridas till omkringliggande miljöer på samma sätt som vägsalt gör. Därmed syftar projektet till att observera den elektriska resistiviteten och konduktiviteten som vägsalt ger upphov till, för att spåra utbredningen av vägsaltet och andra vattenlösliga trafikrelaterade föroreningar, samt dess påverkan på närliggande miljöer. Mätmetoderna som användes var CVES som bidrog med resistivitetsvärden samt EM som bidrog med konduktivitetsvärden. Mätningarna utfördes vid tre tillfällen; kring Arningevägen, E18 samt Skålhamravägen. På grund av tekniska fel har dock färre resistivitetsmätningar gjorts vid E18 i jämförelse med de andra vägarna som undersöktes. Resultatet från och analys av mätningar från respektive mätmetod presenteras visuellt i figurer med hjälp av programmen Res2DInv, Voxler och Surfer. Från dessa figurer kan slutsatser kring föroreningars potentiella spridning dras. Samtliga mättillfällen visade att utbredningen av vägsalt, och därmed föroreningar, spårades till områden närmast vägkanten men även ner till grundvattnet. Ett antal felkällor och begränsningar har påverkat resultatet, exempelvis att metoderna som användes i detta arbete inte undersöker exakta mängder av föroreningar. Detta eftersom mätmetoderna som har används är indirekta metoder som syftar till att spåra vägsalt. Vägarnas storlek och trafikmängd har även vägts in och överläggs kring hur dessa påverkat resultaten. Det framkommer att ju mer trafikerad en väg är desto mer sprids vattenlösliga vägrelaterade föroreningar. Det diskuteras även om hur omkringliggande miljö kan påverkas samt vilka av Sveriges miljömål och de globala målen är av relevans och motverkas. / When planning road infrastructure, traffic-related emissions originating from road and tire wear, as well as anti-skid mitigations, should be taken into account in order to achieve real sustainable development. Examples of road-related emissions are aluminum, lead, copper, cadmium, chromium and zinc. In Sweden, around 200,000 - 230,000 tonnes of salt per year are spread on roads to prevent slippage during the winter. Water-soluble pollutants are assumed to spread to surrounding environments the same way as road salt does. Thus, the project aims to observe the electrical resistivity and conductivity that road salt gives rise to, in order to trace  the distribution of road salt and other water-soluble traffic-related pollutants, as well as its impact on nearby environments. The measurement methods used were CVES which provided resistivity values  and EM which provided conductivity values. The measurements were performed on three occasions; around Arningevägen, E18 and Skålhamravägen. Due to technical errors however, fewer resistivity measurements have been made at E18 in comparison with the other roads that were investigated. The results and analysis from each measurement method are presented visually in figures using the programs Res2DInv, Voxler and Surfer. From these figures, conclusions can be drawn about the potential spread of pollutants. All measurement occasions showed that the distribution of road salt, and thus pollution, was traced to areas closest to the roadside but also down to the groundwater. A number of sources of errors and limitations have affected the result, for example that the methods used do not examine exact amounts of pollutants. This is because the measurement methods that have been used are indirect methods that aim to detect road salt. The size and amount of traffic on the roads have also been weighed in and discussed as to how these have affected the results. It appears that the busier a road is, the more water-soluble road-related pollutants are spread. It is also discussed how the surrounding environment can be affected and which of Sweden's environmental goals and Sustainable Development Goals are relevant and counteracted.

Syftet med denna studie var att undersöka effekterna av driftsparametrar på ett antal mätbara askrelaterade parametrar i dieselpartikelfilter (DPF) i tunga fordon. Tidigare studier visar att askans packningsdensitet, askflöde och hur askan fördelas inuti ett DPF är beroende av parametrar som temperatur, avgasflöde och oljeförbrukning ett fordon har. Det finns anledning att tro att dessa parametrar också påverkas av hur ett fordon används, varför olika driftsparametrar analyserades för korrelation med de uppmätta askparametrarna. De driftsparametrar som undersöktes i denna studie var medelhastighet, antal stopp per 100 km, tomgångsprocent och bränsleförbrukning. Studien startade med metodutveckling av mätning av askvikter hos DPF och jämförde tre olika metoder, benämnda I, II och III. Metod II, som innebar att väga en bit av ett filter före och efter rengöring av filterstycket från aska med tryckluft valdes som den mest pålitliga och användbara metoden eftersom den var snabbare, behövde mindre av varje DPF för att ge kompletta resultat och kunde användas vid analys av DPF-prover som inte hade undersökts innan de användes i ett fordon. Askvikten, tillsammans med den volymetriska fyllningsgraden och genom att känna till inloppsvolymen för ett DPF användes för att beräkna askans packningsdensitet. Fyllningsgraden och askfördelningsprofilen mättes med bildanalys av mikroskopbilder av sågade tvärsnitt av filterstycket. Korrelationsstudien utfördes sedan med dessa metoder och korrelerades med operativa data extraherade från databaser på Scania CV. För att studera vilka parametrar som var korrelerade till varandra utfördes en principal component analysis (PCA) med de operativa och uppmätta variablerna som en matris av data. PCA-analysen visade att tre primalkomponenter (PC) utgjorde &gt;90% av variationen i de erhållna data och att plug/wall-förhållandet, som är ett numeriskt värde för askfördelningen, var starkt positivt korrelerat med ett fordons medelhastighet och negativt korrelerat med antalet stopp, tomgångsprocent och bränsleförbrukning. Vidare visade askflödet en svagare positiv korrelation med tomgångsprocent, antal stopp och bränsleförbrukning medan oljeförbrukningen visade en ännu lägre korrelation med dessa parametrar. Detta indikerar att oljeförbrukningen ej skall ses som en konstant proportionell andel av bränsleförbrukningen för samtliga fordon vid beräkning av serviceintervall för DPFer. Askans packningsdensitet visade ingen till mycket låg korrelation med andra variabler i studien vilket kan bero på att proverna med hög andel väggaska har använts betydligt kortare sträcka än övriga prover, vilket kan ha gjort så att askan inte hunnits packas hårt i filterkanalerna. / The purpose of this study was to investigate the impact of operational parameters on a number of measurable ash related numbers within diesel particle filters (DPFs) of heavy duty vehicles. Previous studies show that ash packing density, ash flow and how the ash is distributed inside a DPF is dependent on parameters such as temperature, exhaust flow profiles and how much oil a vehicle consumes. There is reason to believe that these parameters are also affected by how a vehicle is operated which is why different operational parameters were analysed for correlation with the measured ash numbers. The operational parameters that was investigated in this study was average speed, number of stops per 100 km, idling percentage and fuel consumption. The study started with method development of measuring ash weights of DPFs and compared three different methods, named I, II and III. Method II, which relies on weighing a piece of a filter substrate before and after cleaning the filter piece from ash with pressurized air was chosen as the most reliable and useful method as it was faster, needed less of each DPF to complete the analysis and could be used when analysing DPF samples that had not been investigated previous to its use in a vehicle. The ash weight, together with the volumetric filling degree and known inlet volume of the DPF was used to calculate the ash packing density. The filling degree and ash distribution profile was measured with an image analysis of microscope images of sawed cross sections of the filter piece. The correlation study was then performed with these methods and correlated with operational data extracted from databases at Scania CV. To study which parameters were correlated to each other a primal component analysis (PCA) was performed with the operational and measured variables as a matrix of data. The PCA analysis showed that three primal components made up &gt;90 % of variation in the data and that plug/wall ratio, which is a numerical value of the ash distribution, was strongly positively correlated with average speed of a vehicle and negatively correlated with number of stops, idling percentage and fuel consumption. Furthermore, ash flow showed a slight positive correlation with idling percentage, number of stops and fuel consumption while oil consumption showed an even slighter correlation with these parameters. This indicates that the oil consumption cannot be taken as a constant value as percentage of fuel consumption when calculating service intervals of DPFs. The ash packing density showed none to very low correlation with any other variables in the study, which could depend on the fact that the DPFs with high percentage of wall ash had a significantly lower runtime which could mean that the ash has not had time to be packed tightly in the filter channels.