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Atsitiktinių dydžių, sąlygojančių automobilio stabdymo parametrus, įvertinimas ir analizė / The estimation and analysis of casual factors of car bvraking parametersKudarauskas, Nerijus 17 June 2005 (has links)
Annotation. This thesis presents some analysis of car braking process: a number of analythical formulas and graphic illustrations, discussion on different modes of braking, wider analysis of the main factors, having influence on the braking process. The main parameters and characteristic features, such as steady deceleration, driver’s reaction time, time of deceleration increase, restopping time and others, are also examined, values of most of them were specified during experimental research. A number of dependency graphs and numerical data, recommended for use in calculations performed during the examination of road accidents (and so improving the accuracy of the methods) was also presented.
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Framställning och analys av CTG med EKG-registrering från djurmodell / CTG Representation and Analysis with ECG Recording from Animal ModelGonzálvez Läth, Ania, Sadegh Bozorgi, Saman January 2022 (has links)
Kardiotokografi (CTG) används idag under graviditet och förlossning för att övervaka fostrets hjärtfrekvens i förhållande till livmoderns värkar. Kurvan som erhålls av CTG-apparaten utvärderas av barnmorskan eller läkaren för patologiska mönster. Om CTG-kurvan är för avvikande kan det finnas misstanke om att fostret inte får tillräckligt med syre i livmodern. Dessa avvikelser är dock inte alltid ett tecken på att fostret inte mår bra vilket försvårar tolkningen av kurvorna för personalen. I detta arbete skapades en CTG-kurva utifrån en EKG-registrering gjort på ett lamm för att undersöka om metoden ger en tydlig CTG-kurva. Sedan analyserades kurvan för eventuella patologiska mönster. Resultatet blev en CTG-kurva med avvikelser. De patologiska mönster relaterade till variablerna basal hjärtfrekvens, acceleration och deceleration som förekom i hjärtfrekvenskurvan kunde återges i en graf med tillfredsställande kvalitet. / Cardiotocography (CTG) is used today during pregnancy and labour to monitor the fetal heartbeat in relation to uterine contractions. The graph obtained by the CTG machine is evaluated by the midwife or doctor for pathological patterns. If the CTG graph is too abnormal, there may be a suspicion that the fetus is not getting enough oxygen in the uterus. However, these abnormalities are not always a sign that the fetus is not feeling well, which makes the interpretation of CTG graphs difficult for the medical personnel. In this paper, a CTG graph was created based on an ECG recording taken on a lamb in order to investigate whether this method gives a clear CTG graph. The graph was then analyzed for any pathological patterns. The result was a CTG graph with deviations. The pathological patterns relating to the variables baseline heart rate, acceleration and deceleration that appeared in the heart rate curve could be represented in a graph with satisfactory quality.
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Entwicklung einer Niederenergie-Implantationskammer mit einem neuartigen BremslinsensystemBorany, Johannes von, Teichert, Jochen 31 March 2010 (has links) (PDF)
In diesem Report wird eine Niederenergie-Implantationskammer (NEI-Kammer) beschrieben, die im Forschungszentrum Rossendorf entwickelt und aufgebaut wurde. Die Kammer ermöglicht es, die Implantation von Ionen bei niedrigen Energien (< 30 keV) mit einer Implantationsanlage für mittlere Energien durchzuführen. In der Kammer werden der Ionenstrahl, den der Implanter liefert, auf die erwünschte niedrige Energie abgebremst. Dazu wird ein elektrostatisches Bremslinsensystem eingesetzt, das auf einem neuartigen Prinzip basiert. Das System besteht aus einer Sammellinse und einer Zerstreuungslinse, wobei die Öffnungsfehler beider Linsen entgegengesetzte Vorzeichen besitzen und sich gegenseitig kompensieren. Dadurch ist es möglich, Wafer gebräuchlicher Größe bei geringer Energie mit hoher Dosishomogenität zu implantieren. Die NEI-Kammer ist insbesondere für Forschungseinrichtungen eine vorteilhafte Lösung, da sie eine wesentlich kostengünstigere und flexiblere Alternative zur Anschaffung einer Niederenergie-Implantationsanlage darstellt.
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A model for simulation and generation of surrounding vehicles in driving simulatorsOlstam, Johan January 2005 (has links)
Driving simulators are used to conduct experiments on for example driver behavior, road design, and vehicle characteristics. The results of the experiments often depend on the traffic conditions. One example is the evaluation of cellular phones and how they affect driving behavior. It is clear that the ability to use phones when driving depends on traffic intensity and composition, and that realistic experiments in driving simulators therefore has to include surrounding traffic. This thesis describes a model that generates and simulates surrounding vehicles for a driving simulator. The proposed model generates a traffic stream, corresponding to a given target flow and simulates realistic interactions between vehicles. The model is built on established techniques for time-driven microscopic simulation of traffic and uses an approach of only simulating the closest neighborhood of the driving simulator vehicle. In our model this closest neighborhood is divided into one inner region and two outer regions. Vehicles in the inner region are simulated according to advanced behavioral models while vehicles in the outer regions are updated according to a less time-consuming model. The presented work includes a new framework for generating and simulating vehicles within a moving area. It also includes the development of enhanced models for car-following and overtaking and a simple mesoscopic traffic model. The developed model has been integrated and tested within the VTI Driving simulator III. A driving simulator experiment has been performed in order to check if the participants observe the behavior of the simulated vehicles as realistic or not. The results were promising but they also indicated that enhancements could be made. The model has also been validated on the number of vehicles that catches up with the driving simulator vehicle and vice versa. The agreement is good for active and passive catch-ups on rural roads and for passive catch-ups on freeways, but less good for active catch-ups on freeways.
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Etude des interactions multi-sensorielle pour la perception des mouvements du véhicule en simulateur dynamique : contribution de l'illusion somatogravique à l'immersion en environnement virtuelStratulat, Anca 06 October 2011 (has links)
Les simulateurs de conduite permettent d’explorer certains domaines de recherche difficiles à appréhender en conditions réelles, comme l'intégration de différents signaux sensoriels (ex. visuel, vestibulaire, somesthésique) pour la perception du mouvement. Malgré leur complexité, les simulateurs de conduite ne produisent pas toujours une sensation de conduite réelle, spécialement dans les situations comportant des freinages ou des virages. Leurs limites mécaniques en sont la cause. En conséquence, les lois de mouvement des simulateurs sont basées sur la technique de la « tilt-coordination ». Cette technique consiste à incliner un véhicule de telle sorte que la force gravitationnelle soit équivalente à l’accélération gravito-inertielle (GIA) résultant d’une accélération linéaire. La « tilt-coordination » se base sur l'ambigüité perçue par le système vestibulaire entre un basculement et une translation. Sur simulateur de conduite, l'algorithme « washout » combine la « tilt-coordination » à des translations pour produire une sensation d'accélération linéaire. L'objectif de ces travaux de recherche est d'atteindre une meilleure compréhension de l'intégration multisensorielle pour la perception des accélérations linéaires en simulateur de conduite. Les expériences présentées ci-dessous montrent que la perception des décélérations linéaires dépend de la manière dont le basculement et la translation sont combinés pour produire une perception cohérente. Par ailleurs, nos résultats montrent qu'il y a une différence importante dans la perception des accélérations et des décélérations. Pour le freinage, le rapport basculement/translation le plus réaliste dépend du niveau de décélération. Pour l'accélération, le mouvement est généralement surestimé et dépend du niveau d'accélération. Dans ce cas, la perception ne dépend pas du rapport basculement/translation. Ces résultats suggèrent que les signaux visuels, vestibulaires et somesthésiques sont intégrés de façon Bayésienne. En conclusion, il n'est pas conseillé d'utiliser l'algorithme « washout » sans prendre en compte la non-linéarité de la perception humaine. Nous proposons un modèle qui décrit la relation entre le basculement, la translation et le niveau d'accélération ou décélération souhaité. Ce modèle peut être utilisé pour améliorer la loi du mouvement afin de produire des simulations de conduite plus réalistes. / Driving simulators allow the exploration of certain areas of research that are difficult to reach in normal conditions, like the integration of different sensory inputs (visual, vestibular and somesthesic) for perception of self-motion. In spite of their complexity, driving simulators do not produce a realistic sensation of driving, especially for braking and turnings. This is due to their mechanical limitations. As a consequence, driving simulators' motion algorithm is based on tilt-coordination technique, which assumes the tilt of the car so that the driver's force of gravity is oriented in the same way as the gravito-inertial acceleration (GIA) during a linear acceleration. This technique is based on the tilt-translation ambiguity of the vestibular system and is used on dynamic driving simulators in combination with linear translations in so-called washout algorithm, to produce a sensation of linear acceleration. The aim of the present research is to understand how humans use multiple sensory signals (vestibular, visual and somatosensory) during the perception of linear acceleration on a driving simulator. The conducted experiments show that the perception of motion depends on the manner tilt and translation are used together to provide a unified percept of linear acceleration. Further, our results show that there is an important difference on how humans perceive accelerations and decelerations. For braking, the most realistic tilt/translation ratio depends on the level of deceleration. For acceleration, the motion is generally overestimated and depends on the level of acceleration, but not on the variation of tilt/translation ratio. The results suggest that visual, vestibular and proprioceptive cues are integrated in an optimal Bayesian fashion. In conclusion, it is not advisable to use a washout algorithm without taking into account the non-linearity of human perception. We propose an empirically found data-driven fitting model that describes the relationship between tilt, translation and the desired level of acceleration or deceleration. This model is intended to be a supplement to motion cueing algorithms that should improve the realism of driving simulations.
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Analýza vlivu nesprávného použití a huštění pneu na stabilitu vozidla v mezní situaci / Analysis of the influence of misuse and tire inflation on the stability of the vehicle in a limit situationPorč, Karel January 2021 (has links)
This diploma thesis focuses on incorrect inflation and incorrect use of tires in extreme situations. In the first part, a search of previously created works is reported. This is followed by the elaboration of the basic theory, which describes the driving dynamics of the vehicle, braking and construction, marking, wear and inflation of tires. The next part is the measurement and evaluation of the effect of incorrect inflation and use of tires. Braking deceleration and evasive maneuvers were performed as tests. The third part is an evaluation and summary of the situation.
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Analýza rozjezdu a vybraných manévrů cyklistů / Analysis of Selected Manoeuvres of BicyclistsDoseděl, Jan January 2017 (has links)
Master thesis titled “Analysis of selected manoeuvres of bicyclists” in the first part deals with the history of bicycles, construction, division of bicycles and introduces–traffic accidents of cyclists and national legislation. Practical measurements with bicyclists is in the second part of this thesis. Cyclists performed deceleration on three surfaces, acceleration and a manoeuver, in which cyclist looked behind himself before changing the direction. The evaluation of all measurements and comparison with other similar works has been made in the last chapters.
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Analýza doby příčného přemístění motocyklů / Analysis of the Lateral Displacement Time of MotocyclesFriedel, Daniel January 2013 (has links)
Diploma thesis named Analysis of the lateral displacement time of motorcycles captures formation and development of motorcycles, description of construction and proper techniques for riding a motorcycle. The main aim of this work is to organise and perform the measurement of the lateral displacement and deceleration of the motorcycles. These values will serve for forensic experts. Before the measurement was proposed methodology for the measurement of the lateral displacement by used two cameras and long chalk line. Follow measurement and evalution measurement of the lateral displacement and deceleration. Outputs from this thesis are values of the lateral acceleration necessary for calculation of the shortest lateral displacement time of the motorcycle and 96 videos with course and result of measurements.
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Měření zpomalení osobních automobilů při brzdění motorem / The Measurement of Car Deceleration During Engine BrakingBejčková, Jana January 2014 (has links)
The presented diploma thesis deals with the measurement of car deceleration during engine braking from different starting speeds and different speed gears with a sample of vehicles. This piece of work consists of a theoretical part, where problem background is defined, selected driving parameters including the manner how to measure them are explained and the facts in the field of structural characteristics of the vehicle are given, further from a design of measurement methodology that gives an overall plan of implementation, all the respective information and a description of handling with decelerometer, further from a real measurement of the deceleration including an interpretation of partial obtained values and finally from the evaluation of all results with appropriate conclusions.
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Měření zpomalení motocyklů při brzdění motorem / Measuring the Deceleration of Motorcycles with the Use of Engine BrakingVašica, Radoslav January 2014 (has links)
Diploma thesis deals with the deceleration of the motorcycles with the use of engine braking. Work can by divided into theoretical and practical part. The theoretical part begins with the possibility of division motorcycles according to several criteria. Below is given the primary papers of literature, usable in connection with the issue of this work. Subsequently, the work discusses the factors which are affecting the course of the deceleration with the use of engine braking. The practical part acquaints the reader with available measuring devices, with the place of measurement and the methodology. The following are listed specific measured values for individual motorcycles, supplemented with graphical output. At the end of the practical part is for comparison a brief summary of the measured values of each tested vehicle. Interpretation and evaluation of the measured data are contained in the conclusion of the work.
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