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1

Snyder, Sara Ann. "Examining the impacts of State Route 101 on wildlife using road kill surveys and remote cameras." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1296.

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Roads can negatively impact the survival of wildlife populations through additional mortality from road kill and population fragmentation caused by road avoidance behaviors. The 11.9 mile section of State Route 101 between the towns of San Luis Obispo and Atascadero, CA, USA, cross a mountain lion movement corridor and an area important to maintaining ecological connectivity between protected lands in the Los Padres National Forest to the north and south. I examined the spatial patterns and landscape and roadway factors associated with road kill occurrence for six taxa; large mammals, mesocarnivores, squirrels, rabbits, birds and raptors. Between 1 May 2009 and 30 June 2010 road kills were documented using vehicle-based surveys. Small mammals were the most common road kill (58.3%), followed by mesocarnivores (10.9%), birds (10.6%), rabbits (5.1%), large mammals (3.3%) and raptors (3.2%). Twenty-nine large mammal road kills were observed during the survey period; eighteen mule deer, six black bears and five feral pigs. Road kill was highest in the middle of the survey area between the top of Cuesta Grade and the southern edge of Atascadero and lowest along the Cuesta Grade. I modeled road kill occurrence using logistic regression to determine which landscape and roadway characteristics were associated with road kill locations. Large mammal and mesocarnivore road kills were more likely to occur near riparian corridors. Mesocarnivore and squirrel road kills were associated with locations with greater roadside tree cover. Squirrel and rabbit road kills were more likely to occur along sections of the road with large grassy center medians. I documented animal activity patterns around the roadway during three survey periods (summer 2009, fall 2009 and spring 2010) using remote cameras placed on game trails and underpasses along the roadway. Mule deer displayed crepuscular activity patterns with peaks in activity in the morning between 05:00h and 07:00h and in the evening between 16:00h and 18:00h. Mesocarnivores generally displayed a nocturnal activity patterns with the majority of activity occurring between 18:00h and 06:00h. I used logistic regression to determine if there was a relationship between animal activity patterns and traffic patterns while controlling for time of day, day of the week, and season. Mule deer and mesocarnivore activity patterns varied significantly by time of day and mule deer activity also varied significantly by season; however only mesocarnivore activity varied significantly in relation to traffic volume suggesting that mesocarnivores are less activity when traffic volume is high. Using traffic volume and animal activity patterns I calculated a collision potential value for both mule deer and mesocarnivores. Collision potential for mule deer was high in the morning, between 06:00h and 08:00h, and in the evening, between 16:00h and 18:00h in all three seasons. Collision potential for mesocarnivores was high in the evening in fall 2009 (18:00h and 21:00) and spring 2010 (17:00h), and high in the morning in summer 2009 (09:00h).
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2

Wills, Johnny. "DNA-based hair sampling to identify road crossings and estimate population size of black bears in Great Dismal Swamp National Wildlife Refuge, Virginia." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/34932.

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The planned widening of U.S. Highway 17 along the east boundary of Great Dismal Swamp National Wildlife Refuge (GDSNWR) and a lack of knowledge about the refugeâ s bear population created the need to identify potential sites for wildlife crossings and estimate the size of the refugeâ s bear population. I collected black bear hair in order to collect DNA samples to estimate population size, density, and sex ratio, and determine road crossing locations for black bears (Ursus americanus) in GDSNWR in southeastern Virginia and northeastern North Carolina. I also investigated bear/vehicle collisions to determine patterns of road crossing.

Genetic analysis of 344 hair samples collected on 2 trapping grids identified 85 unique individuals which I used in a mark-recapture analysis. Estimated population size on the trapping grids was 105 bears (95% CI = 91-148) and average density was 0.56 bears/km2. This density estimate projected over the entire Great Dismal Swamp ecosystem yielded a population estimate of 308 bears (550 km2 X 0.56 bears/km2). Similar population estimates generated by Hellgren (1988), Tredick (2005), and this study suggest a stable bear population in the Great Dismal Swamp ecosystem over a 20-year period.

I erected a 2.3-kilometer long strand of barbed wire along U. S. Highway 17 to monitor road crossing patterns near the Northwest River drainage. Genetic analysis identified 6 bears (4 males, 1 female, 1 unknown) that apparently crossed the highway in a 10-month period. Five of 6 bears deposited hair in a 171-m section which included the Northwest River corridor. The 6 bears detected crossed the road at least 11 times.

I investigated 10 reports of bear/vehicle collisions on the periphery of the refuge from June 2000 to May 2002. Six bears (4M:1F:1 unknown) were confirmed killed during this time period. Based on reported bear/vehicle collisions from Hellgren (1988), the Virginia Department of Game and Inland Fisheries database, and this study, a minimum of 4 to 5 bears are struck by vehicles each year on the periphery of the refuge. I identified 2 areas of multiple bear/vehicle collisions: highway 58 on the north side of the refuge near Hampton Airport and Highway 17 on the eastern side of the refuge in the vicinity of the Northwest River corridor.
Master of Science

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3

Youssef, Dalal. "Améliorer la sécurité routière au Liban : un parcours multidimensionnel allant de l'analyse exhaustive des défis à l'intégration des données et l'examen du comportement des conducteurs." Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0268.

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Les collisions de la route, une préoccupation mondiale en matière de santé publique et de socio-économie, coûtent la vie à 1,19 million de personnes chaque année. Le Liban, avec une population de moins de 6 millions d'habitants, enregistre chaque année près de 1 000 décès dus aux collisions de la route. Les défis sont exacerbés par la croissance démographique, la possession de véhicules au sein des foyers, la détérioration des infrastructures et les conflits régionaux, le tout compliqué par des données fragmentées. Le manque de recherches antérieures sur la sécurité routière aggrave la situation en entravant la formulation de politiques éclairées. En utilisant une approche multidimensionnelle, cette thèse entreprend une exploration exhaustive des défis de la sécurité routière, visant à combler les lacunes de la recherche et s'efforce de fournir une stratégie holistique pour améliorer la sécurité routière. Sa vision ultime s'étend à des routes plus sûres, à une réduction des décès et à l'évolution vers un système de transport durable. La thèse se déploie en deux axes principaux : le système de management de la sécurité routière et le comportement des conducteurs. Dans le premier axe, une analyse exhaustive de la situation actuelle du système de management de la sécurité routière au Liban a été réalisée. Cette analyse examine en profondeur les défis, ainsi que les complexités historiques, institutionnelles, organisationnelles et financières qui influencent le cadre actuel de la sécurité routière. La thèse évalue les mécanismes d'application du code routier, les affectations budgétaires et propose des recommandations fondées sur des données probantes pour améliorer à la fois la sécurité routière et la durabilité au Liban. Cette analyse exhaustive souligne l'urgence d'adopter une stratégie holistique couvrant un large éventail d'aspects liés à la sécurité routière, de l'application rigoureuse des lois à l'amélioration des infrastructures, en passant par l'allocation durable des financements et la collaboration internationale active. Reconnaissant que les données soient la pierre angulaire d'une gestion efficace de la sécurité routière, la thèse aborde brièvement le problème crucial de la fragmentation et de l'incomplétude des données sur les traumatismes liés à la circulation routière au Liban. Se penchant sur le facteur humain, le deuxième axe se concentre sur le comportement des conducteurs, élément essentiel de la sécurité routière qui a manqué d'outils validés dans le contexte libanais. La thèse comporte l'adaptation transculturelle de quatre échelles de mesure (le locus de contrôle du trafic, le questionnaire sur le comportement des conducteurs, l’échelle de la colère au volant et l'inventaire des compétences des conducteurs) pour comprendre et atténuer les comportements dangereux des conducteurs. Ce processus complexe implique la traduction, l'adaptation transculturelle, une validation rigoureuse et l'implication de divers groupes de conducteurs libanais dans la collecte de données. Au-delà de la validation, elle explore l'association entre ce comportement et les collisions de la route, avec le potentiel d'influencer les politiques de sécurité routière et de promouvoir de bonnes pratiques de conduite. Cette thèse sert alors de plan directeur transformateur, visant à forger des routes plus sûres, à réduire les collisions et à améliorer la qualité de vie au Liban. Il s'agit d'un appel sans équivoque à répondre à l'urgence d'agir et à promouvoir des solutions fondées sur des données probantes
Road traffic collisions, a global public health and socio-economic concern, claim 1.19 million lives annually worldwide. Lebanon, with a population under 6 million, contends with nearly 1,000 road fatalities each year. Challenges are amplified by population growth, increased household vehicle ownership, deteriorating infrastructure, and the enduring impact of regional conflicts, all further obscured by fragmented data. The dearth of prior research on Lebanese road safety compounds the predicament, impeding informed policy formulation and precise solutions. The thesis unfolds along two main axes: road safety management and driver behaviour. The first axis provides a comprehensive analysis of the current state of road safety management in Lebanon. This analysis delves deeply into the challenges, as well as the historical, institutional, organizational, and financial complexities that shape the current framework for road safety. The thesis evaluates existing policies, enforcement mechanisms, budget allocations, and proposes evidence-based recommendations to improve both road safety and sustainability in Lebanon. This thorough analysis highlights the urgent need for a holistic strategy that covers a wide range of road safety aspects, from strict law enforcement to infrastructure improvements, sustainable funding allocation, and active international collaboration. Recognizing that data is the cornerstone of effective road safety management, the thesis addresses briefly the critical issue of fragmented and incomplete data on road traffic injuries in Lebanon. Focusing on the human factor, the second axis concentrates on driver behaviour, a key element of road safety that has lacked validated tools in the Lebanese context. The thesis advocates for the cross-cultural adaptation of four measurement scales (Traffic Locus of Control, Driver Behaviour Questionnaire, Driving Anger Scale, and Driver Skills Inventory) to understand and mitigate risky driver behaviours. This complex process involves translation, cross-cultural adaptation, rigorous validation, and the involvement of various groups of Lebanese drivers in data collection. Beyond validation, it explores the relationship between driver behaviour and road collisions, with the potential to influence road safety policies and promote good driving practices. This thesis thus serves as a transformative roadmap, aiming to create safer roads, reduce collisions, and improve the quality of life in Lebanon. It is a clarion call to address the urgent need for action and the pursuit of data-driven solutions
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4

Despringre-Bessière, Karine. "Détection d'obstacles sur route par télémétrie laser : évaluation des caractéristiques d'un système intégré." Grenoble INPG, 1996. http://www.theses.fr/1996INPG0071.

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Les caracteristiques d'un systeme de detection d'obstacles sur autoroute, a grande vitesse, sont evaluees. La technologie de base est la telemetrie laser temps de vol, utilisee au leti. Un bilan sur la securite routiere en france souligne le besoin des usagers pour ce type de systeme. La revue sur les systemes de detection d'obstacles experimentaux actuels montre leurs limitations pour l'application autoroutiere. Les capteurs telemetriques developpes au leti sont ensuite presentes. Un systeme a balayage multiligne, base sur une evolution de ces capteurs, est propose, pour repondre au besoin defini. Le systeme est informatif. Le contexte de fonctionnement du systeme est decrit precisement, ainsi que ses objectifs et les contraintes qu'il doit tenir. Une description fonctionnelle est presentee. Le systeme est constitue de trois parties: (1) la partie acquisition, qui comporte essentiellement la mesure de distance et le balayage, (2) la partie traitement, constituee de la detection et du suivi des obstacles puis de l'estimation du danger qu'ils representent (3) et enfin la partie visualisation des informations pour le conducteur. Le simulateur sitam (simulateur d'images telemetriques acquises en mouvement), developpe lors de la these pour valider l'approche, est presente ensuite. Le systeme d'acquisition est dimensionne. Ainsi les parametres necessaires au systeme sont determines dans les conditions de fonctionnement definies auparavant. En particulier, le champ de vue est defini (en site, azimut et profondeur), ainsi que la frequence d'echantillonnage et la puissance adequates. Une etude parametrique est effectuee. Des simulations permettent d'evaluer la variation de la zone percue en fonction des variations des parametres du systeme. Des solutions sont proposees pour le traitement des donnees fournies par le futur capteur defini
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5

Gupta, Anil K. "An algorithm to solve traveling-salesman problems in the presence of polygonal barriers." Ohio : Ohio University, 1985. http://www.ohiolink.edu/etd/view.cgi?ohiou1184007096.

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6

Augé, Patrick. "Spécification, modélisation et vérification d'une architecture multi-agents dédiée à la gestion des risques de collision automobile." Paris 11, 2001. http://www.theses.fr/2001PA112345.

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L'informatique prend une place importante dans les systèmes de divers secteurs d'activités, des dispositifs sophistiqués de l'industrie spatiale sont ainsi pilotés par des systèmes informatiques. Le bon fonctionnement repose alors sur le comportement correct de ces derniers. Aussi, la place des méthodes de vérification est importante, car apportant une garantie de bon fonctionnement rigoureuse et exhaustive, basée sur une approche théorique solide et des outils de génie logiciel réalisant les fondements théoriques. Dans le schéma de la vérification, un modèle du système est décrit dans un langage où la sémantique opérationnelle associe au modèle un graphe d'états, décrivant toutes les exécutions possibles, dans lequel peuvent être identifiés des séquences ou des états prohibés. La construction de ce graphe peut conduire à l'explosion combinatoire. Cette étape clé prend donc une place prépondérante dans les travaux de cette thèse où sont considérées différentes stratégies, de construction avec réduction, basées sur des ordres partiels et des relations d'équivalences : des outils de vérification les implantant ont été confrontés, par rapport à différentes études de cas classiques. Une étude de cas conséquente a été aussi menée sur un système basé agents d'aide à la conduite automobile, amenant à aborder des aspects spécification, construction de graphe et vérification. Cette étape a associée des spécialistes de communautés différentes, mettant en relief divers éléments d'un processus de conception de systèmes complexes. Cette collaboration a permis de définir les abstractions, en se focalisant sur le contrôle des interactions des agents, permettant ainsi la réduction de la taille du graphe d'états, rendant alors possible la vérification. La modélisation, dans les langages des outils visés du parallélisme des traitements, nous a aussi conduit à proposer plusieurs versions de schémas de contrôles et leurs vérifications ont toutes réussies
Computer sciences take a rising place in various industrial systems, complex spatial equipment are for instance controlled by computer systems. The equipment operates correctly when the behavior of the computer part is correct. Thus, verification methods are of great importance, as they prove the correct behavior according to rigorous and exhaustive analyses based on strong theories, the methods also bring appropriated tools. Within the verification scheme, a model of the system is described using languages which semantics associate to the model a state graph that represents all possible executions. This space makes it possible the identification of such states or sequences which are not allowed. The construction of this graph may lead to the combinatorial explosion problem. This key step takes thus preponderant place in this thesis, here are considered various construction strategies with reduction, based on partial orders and equivalency relations : verification tools implementing these strategies are compared according to various classical case studies. A more complex case study, that concerns an agent based system dedicated to road collision risks management, has also been dealt with. Consequently, specification, graph construction and verification aspects were considered. This part of the study associates researchers from different areas, highlighting key points of complex systems design. This collaboration allowed the definition of abstractions, focusing on interactions, reducing thus the size of state graphs, making possible the verification step. Modeling, within tools languages, of parallel processing, led us to propose several control schemes which verifications all succeeded
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7

Revue, Alexandre. "Contribution des systèmes d'information géographiques à la sécurité routière : approche multicapteurs pour l'évaluation de configurations à risques." Paris, ENMP, 2003. http://www.theses.fr/2003ENMP1147.

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8

Poulard, David. "Influence de l’âge et du morphotype sur la réponse mécanique du thorax : étude expérimentale in vivo et analyse numérique à l'aide de modèles EF personnalisés du corps humain." Thesis, Lyon 1, 2012. http://www.theses.fr/2012LYO10332/document.

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Cette étude aborde le problème de l’aggravation du risque de fractures de côtes chez les automobilistesâgés en choc frontal. L’analyse de la bibliographie fait ressortir que les moyens actuels d’évaluationdu risque de fractures ne permettent pas de prendre en compte les différences anatomiques et depropriétés mécaniques du thorax observées chez les personnes âgées. Les modèles éléments finis (EF)personnalisés du corps humain offrent un grand potentiel en tant qu’outil avancé d’évaluation durisque de blessures. Toutefois, des données expérimentales sont nécessaires pour valider ces modèlesdans des conditions réalistes. De plus, le choix du niveau de personnalisation et la sensibilité de laréponse du modèle à celle-ci doivent être évaluées.Des expérimentations in vivo menés sur des volontaires ceinturés en choc léger, de différents âges etanthropométries, ont été réalisées. Ces tests ont permis d’étudier l’influence de l’âge et de lacorpulence sur la réponse mécanique du thorax et ont permis l’obtention de corridors nécessaires à lavalidation de modèles EF personnalisés. La géométrie du modèle numérique THUMS a été adaptée àcelle des volontaires et les propriétés mécaniques du thorax ont été modifiées au vu du vieillissementpour effectuer une analyse similaire dans le domaine lésionnel. Les simulations numériques ont mis enévidence un risque accru de fracture de côtes pour certains modèles personnalisés.Cette étude devrait permettre de mieux estimer le risque de blessure pour les automobilistesvulnérables. Elle devrait contribuer ainsi à promouvoir les modèles personnalisés du corps humaincomme outil avancé d’évaluation du risque de blessures
This study deals with the topic of increased risk of rib fractures among elderly drivers infrontal impact. The analysis of the literature reveals that actual thorax injury assessment tools do nottake into account for the differences in anatomical features and biological material properties observedbetween adults and elderly. Personalized human body finite element (FE) models have great potentialas improved thorax injury assessment tools. However, experimental data are needed to validate thesemodels under real-world conditions. In addition, the choice of the level of personalization of the modeland the sensibility of the model response to this personalization must be assessed to predict thoracicinjury risk.In vivo sled tests were performed on belted volunteers of various anthropometries and age. These testswere used to assess the influence of age and corpulence on thorax mechanical response and allowed toobtain corridor responses needed to validate personalized FE models. The geometry of the FE modelTHUMS was adapted to the volunteers and the thorax material properties were modified consideringaging to carry out a similar analysis in the injurious domain. Numerical simulations highlighted anincreased risk of rib fractures for specific personalized models.This study should help to better estimate the injury risk for car occupants. It should contribute topromote personalized human body models as attractive thorax injury assessment tool ofvulnerable individuals
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Hartmann, Jean-Michel. "Etude de l'absorption infra-rouge par des mélanges gazeux HO-CO-CO-Air à température élevée modélisation, pour l'ingénieur, des propriétés radiatives, approches théorique et expérimentale de l'élargissement par collisions." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37599390v.

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Revue, Alexandre. "Contribution des systèmes d'informations géographiques à la sécurité routière : approche multicapteurs pour l'évaluation de configurations à risques." Phd thesis, École Nationale Supérieure des Mines de Paris, 2003. http://pastel.archives-ouvertes.fr/pastel-00000833.

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Hartmann, Jean-Michel. "Etude de l'absorption infra-rouge par des mélanges gazeux H2O-CO2-CO-Air à température élevee : modélisation, pour l'ingenieur, des propriétés radiatives : approches théorique et expérimentale de l'élargissement par collisions de raies de H2O et CO." Châtenay-Malabry, Ecole centrale de Paris, 1986. http://www.theses.fr/1986ECAP0013.

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Etude de l'absorption IR pour H2O, CO2 et CO gazeux à haute température. Analyse de la validité de modèles simplifiés pour la modélisation des propriétés radiatives de H2O et CO2 à basse résolution. Étude expérimentale de l'élargissement collisionnel de raies IR à haute résolution par diode laser : intensités et coefficients d'élargissement des raies de H2O et CO entre 300 et 900 k. Proposition d'un modèle pour l'élargissement des raies de H2O
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12

Henderson, Ryan Lynn. "Magnolia Star Route." Master's thesis, Mississippi State : Mississippi State University, 2007. http://library.msstate.edu/etd/show.asp?etd=etd-04092007-130126.

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13

Kantak, Advait Ashok. "Wet particle collisions." Diss., Connect to online resource, 2005. http://wwwlib.umi.com/cr/colorado/fullcit?p3190381.

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Nesbitt, Brian. "Heavy-particle collisions." Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301028.

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15

Holmquist, John. "NAVIGATION AIDS IN ROUTE TRAINING: INCREASE NAVIGATION SPEED, DECREASE ROUTE RETENTION?" Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4014.

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In the case of one car following another to a destination, it is very effective at getting the second vehicle to the destination quickly; however, the driver of the second car may not learn the route. Yet, for individuals, such as firefighters, law enforcement, and military personnel, it is imperative that a route be learned quickly and accurately and that an awareness of the situation is maintained while they traverse the given route. This leads to three questions, (a) will navigation aids affect initial route navigation; (b) will navigation aids affect retention; and (c) will navigation aids affect situation awareness while en route? The hypotheses of this study were that navigation aids would significantly increase the speed at which a person can initially navigate a route, but the use of the aids would significantly decrease the retention of the route navigated. The findings of this study support the hypotheses. The results suggest that participants that followed a confederate and participants that were given verbal directions were quicker and made fewer errors than participants that reviewed a map or initially figured the route out on their own (control group). The study also showed that as the participants navigated the route for a second time with no navigational assistance, the ones that reviewed a map or that were in the control group outperformed participants that initially had a confederate to follow or were given verbal directions their first time through. Finally, no real effects were found on the participants' situation awareness during the retention portion of the study.
Ph.D.
Other
Engineering and Computer Science
Modeling and Simulation
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16

Fulati, Tayierjiang. "Route de la soie, route de la création : rencontres, frontières, contacts, croisements." Thesis, Paris 1, 2017. http://www.theses.fr/2017PA01H306/document.

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Cette thèse, qui s'appuie sur ma pratique artistique personnelle, analyse l'identité, l'origine, la valeur et la place de la main dans l'art en sillonnant l'ancienne Route de la soie. J'étudie mon parcours de création artistique, ma culture, mes identités multiples et mes influences au regard de l'héritage légué par La Roule de la soie et la route de La création. La traversée de la Route de la soie s'articule autour de quatre thèmes: la rencontre, le contact, le croisement et la frontière. Les recherches m'ont mené sur un voyage messianique dans le but de répondre aux questions qui me hantaient: l'influence étendue de la Route de la soie sur la création artistique est-elle source de créativité? Comment peut-elle se révéler dans les œuvres d'artistes contemporains? La route de ma création artistique se croise-t-elle avec la Route de la soie? Pour répondre à ces questions, j'ai présenté ma main comme une figure qui me lie à mes origines invisibles. Dans le premier chapitre, j'explore la notion d’identité à travers les portraits de la main, puis j'étudie la notion de frontière visible et invisible. Dans le troisième chapitre, j'analyse le toucher, le goûter et le croisement avec la Route de la soie. Enfin, j'examine le contexte des paysages intérieurs et je tente de mettre en lumière l'héritage caché ainsi que les secrets de l'art local imprégné par la culture de notre région et ce à travers les croisements et les métissages culturels
Relying on my personal artistic practice, this thesis analyzes the identity, origin, the value and the place of the "band" in the art in weaving through the old Silk Road. The analysis of my artistic creation, my culture, my multiple identities and my influences in the light of the legacy of the Silk Road and the road of the creation. The crossing of the Silk Road is structured around four themes : the meeting, contact. The crossing and the border. The research led me on a messianic trip, in the aim of finding answers to the questions that concern me : how the Silk Road influences artistic creation, is it a source of creativity? How can it be in the works of contemporary artists? How it emerges on my artistic creation? To answer these questions, I presented my band as a figure, which binds me to my multiple origins. In the first chapter I will analyze the concept of identity through the portraits of the band, then I will look into the notion of border visible and invisible. In the third chapter, I will analyze the touch, the taste and the crossing with the Silk Road. Finally, I will examine the context of interior landscapes and I will try to demonstrate the hidden legacy as well as the secrets of the local art impregnated in the culture of our region through crosses and cultural mixes
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Tezcaner, Diclehan. "Multi-objective Route Selection." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12610767/index.pdf.

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In this thesis, we address the route selection problem for Unmanned Air Vehicles (UAV) under multiple objectives. We consider a general case for this problem where the UAV has to visit several targets and return to the base. For this case, there are multiple combinatorial problems to be considered. First, the paths to be followed between any pairs of targets should be determined. This part can be considered as a multi-objective shortest path problem. Additionally, we need to determine the order of the targets to be visited. This in turn, is a multi-objective traveling salesperson problem. The overall problem is a combination of these two combinatorial problems. The route selection for UAVs has been studied by several researchers, mainly in the military context. They considered a linear combination of the two objectives
minimizing distance traveled and minimizing radar detection threat
and proposed heuristics for the minimization of the composite single objective problem. We treat these two objectives separately. We develop an evolutionary algorithm to determine the efficient tours. We also consider an exact interactive approach to identify the best paths and tours of a decision maker. We tested the two solution approaches on both small-sized and large-sized problem instances.
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Nikwigize, Adolphe. "Graph theory : Route problems." Thesis, Linnéuniversitetet, Institutionen för datavetenskap, fysik och matematik, DFM, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-17397.

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19

Bottom, Jon Alan. "Consistent anticipatory route guidance." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/31095.

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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000.
Includes bibliographical references (p. 241-251).
Anticipatory route guidance consists of messages, based on traffic network forecasts, that assist drivers' path choice decisions. Guidance is consistent when the forecasts on which it is based are verified after drivers react to it. This thesis addresses the formulation and development of solution algorithms for the consistent anticipatory route guidance generation (RGG) problem. The thesis proposes a framework for the problem, involving a set of time-dependent variables and their relationships. Variables are network conditions, path splits and guidance messages. Relationships are the network loading map, transforming path splits into network conditions; the guidance map, transforming network conditions into guidance messages; and the routing map, transforming guidance messages into path splits. The basic relationships can be combined into three alternative composite maps that model a guidance problem. Consistent guidance corresponds to a fixed point of a composite map. With stochastic maps, RGG model outputs are stochastic process realizations. In this case, the consistency fixed point corresponds to stationarity of the RGG solution process. Numerical methods for fixed point computation were examined, focusing on approaches that are rigorous and applicable to large-scale problems. Methods included Gibbs sampling for highly stochastic maps; generalizations of functional iteration for deterministic maps; and the MSA and Polyak iterate averaging method for "noisy" (deterministic plus disturbance) maps. A guidance-oriented dynamic traffic simulator was developed to experiment with RGG solution methods. Computational tests using the simulator investigated the use of Gibbs sampling to compute general stochastic process outputs; and examined the performance of the averaging methods under different model formulations, problem settings and degrees of stochasticity. Gibbs sampling successfully generated realizations from the stationary solution process of a fully stochastic model, but entails considerable computational effort. For noisy problems, the MSA found fixed points in all cases considered. Polyak averaging converged between two and four times faster than the MSA in low or moderate stochasticity problems, and performed comparably to the MSA in other problems. Formulations involving path-level variables converged more quickly than those involving link-level variables.
by Jon Alan Bottom.
Ph.D.
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20

Hultman, Tim. "Signal-Aware Route Planning." Thesis, Linköpings universitet, Programvara och system, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-128101.

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Modern vehicles have an increasing number of advanced features requiring network coverage in order to function properly. In order to facilitate the requirements of such features and allow more advanced applications, we consider the possibility of planning routes that take signal strength into consideration. Previous work have shown the relationship between TCP throughput/goodput and signal strength. In this thesis signal-aware route planning is presented, implemented, and validated. Crowd-sourced map and signal data (3G) from two sources is used for building a signal coverage map. The signal and map data is validated in a field experiment, where routes were travelled while measuring the signal strength. The field experiment showed gains in signal characteristics when deviating from the shortest possible path. The average signal strength increased by 11 dBm between algorithms and the shortest possible path. Lastly, routes were planned for all possible sources and destinations in a given urban area. The results of this calculation confirms the patterns found in the field experiment.
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Mackman, Richard Laurence. "Isobacteriochlorins : a novel route." Thesis, University of Cambridge, 1992. https://www.repository.cam.ac.uk/handle/1810/272523.

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22

Planchette, Carole. "Collisions de gouttes asymétriques." Phd thesis, Université Paris-Est, 2011. http://tel.archives-ouvertes.fr/tel-00647892.

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Dans cette thèse expérimentale, on s'intéresse aux collisions de gouttes mettant en jeu des interfaces asymétriques, soit deux gouttes constituées de liquide différent ou des gouttes de taille différente et recouvertes (ou non) d'une couche de particules hydrophobes. Dans une première partie, on étudie les collisions de gouttes de liquide immiscible. L'asymétrie de tels systèmes repose alors sur le contraste des propriétés des deux liquides : la tension de surface, la viscosité et la densité. Le résultat de ces collisions est une encapsulation totale d'un liquide par un autre ou une encapsulation suivie d'une fragmentation. On s'attache à décrire les régimes observés et à établir des lois permettant de prédire les limites de fragmentation de l'objet obtenu. La seconde partie est consacrée aux interfaces couvertes de particules hydrophobes. Pour ces systèmes, l'asymétrie réside à la fois dans la présence des particules sur une interface et pas sur l'autre et dans le contraste de taille entre les objets étudiés. Ainsi, on considère l'impact entre une petite goutte (recouverte ou non de particules) et une très grosse goutte (recouverte ou non de particules). On caractérise tout d'abord les propriétés mécaniques de ces interfaces via la propagation d'ondes de surface, notamment en terme de tension de surface effective et de module de courbure. Puis, on sonde, dans différentes situations d'impact, la robustesse de ces objets afin d'évaluer la capacité de ces couches particulaires à prévenir la coalescence
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McGuinness, Philip. "Electron-ion elastic collisions." Thesis, Queen's University Belfast, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268236.

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Copeland, Fiona B. M. "Low energy rearrangement collisions." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318881.

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McAlinden, Mary Trea. "Atomic collisions involving positrons." Thesis, Queen's University Belfast, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317480.

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26

Grishkevich, Sergey. "Ultracold collisions in traps." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2010. http://dx.doi.org/10.18452/16098.

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Die ultrakalte Atom- und Molekülephysik, zu welcher man zum Beispiel bei der Bose-Einstein-Kondensation von verdünnten Gasen Zugang hat, wurde untersucht. In solchen Systemen dominieren Zwei-Körper-Stöße und ihre detaillierte Untersuchung ist eines der zentralen Themen dieser Arbeit. Diese wurden durchgeführt unter Berücksichtigung von elementaren chemischen Reaktionen, Photoassoziation und magnetischen Feshbach-Resonanzen. Weiterhin wurden Untersuchungen von Atomen in optischen Gittern durchgeführt. Die Viel-Teilchen-Systeme wurden nicht nur mit dem üblichen mean-field Ansatz behandelt, sondern auch darüber hinausgehend, um die voll korrelierte Bewegung zu simulieren.
The ultracold atomic and molecular physics as it is accessible, e.g., in Bose-Einstein condensates of dilute gases was investigated. In such systems two-body collisions are dominant and their detailed study is one of the central topics of this work. They were done considering elementary chemical reactions as photoassociation, and magnetic Feshbach resonances. Additionally, studies of atoms in optical lattice sites were carried out. The many-body systems were not only considered within the usually adopted mean-field approach but also beyond that in order to simulate the fully correlated motion.
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O'Connor, Daryl John. "Atomic collisions with surfaces." Thesis, Canberra, ACT : The Australian National University, 1997. http://hdl.handle.net/1885/144473.

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28

Shin, Doh Kyoum. "Explanation of factors influencing cyclists' route choice using actual route data from cyclists." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/13532/.

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Cycling as a sustainable means of transport brings a number of benefits, which includes improved health and well-being for individuals, improved air quality and climate change, accessibility and reduced traffic congestion at the national level. However, despite the benefits of cycling and the efforts by the government to promote this mode of transport, many short trips in Britain suitable for cycling are still made by motorised transport modes. People seem reluctant to change their mode of travel behaviour in favour of cycling. Therefore, it is important to understand the nature of complicated behaviour of people and the ones of cyclists at first. The thesis aimed to understand route choice behaviour for cycling for utility purposes in England. The thesis examined why cyclists use their current routes and how various features influence their choices. The thesis also probed the reasons for the choices and the relationship between the choice and the characteristics of cyclists. A mixed method approach was applied for the thesis, using questionnaires, actual route data collection for quantitative methods and interviews for qualitative methods. This approach allowed the researcher to examine diverse aspects of the research questions, which individual methods were unlikely to address. The thesis has identified what route features are important for cyclists, and why these features are considered important. In terms of the issues regarding cycling infrastructures, the preferences of cyclists were found to be linked to the fear to motorised traffic on roads, which is a fundamental issue that may not be revealed through quantitative studies. Another key finding identified was that cyclists choose different routes dependent on the conditions applicable even for same trip purposes. In this respect, it was noted that often their choices are forced by prevailing road instructions such as one-way road, although they may be aware that the alternative road conditions may not be good from a cycling viewpoint. However, it was also found that, where practicable, cyclists are likely to choose a route strategically, in a manner that will minimise the physical efforts required for cycling. Finally, based on the observations of the different geographical and environmental characteristics and atmosphere to cycling in two case study cities, the thesis also discovered the segment of the population who could become the main target for promoting the benefits of cycling.
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Gillman, Malin. "Eco-route modelling using GIS : How to find the most sustainable route option." Thesis, Umeå universitet, Institutionen för geografi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-185860.

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In a time when the concept of sustainability is gaining increasing attention among the public, as well as among stake holders and policy makers, informing people about what the most sustainable choice to make is, is crucial in leading people in the right direction.  Travelling is an activity requiring a traveller to make multiple choices, with one of the choices being which route between two places to take. The transport sector is also a strong contributing cause to global issues such as climate change, wherefore choices made in relation to transportation are highly relevant in regard to sustainable development.  Up until today, most traffic information systems for passenger car users, only provide travellers with suggestions about the fastest, or the shortest, route option. This study aims at proposing a modelling structure using GIS software, that could also return the most sustainable route alternative.  The complexity of the many spatial impacts of road transportation is thoroughly discussed in the literature review, together with dilemmas regarding route choice behaviours. A proposed modelling structure is presented, with the structure also empirically being examined as a “proof of concept”. The empirical work takes place in the urban area of Hörnefors, Sweden, and findings confirm the applicability of the proposed workflow.  In the specific case of Hörnefors, three distinct route options are investigated, in relation to four sustainability impact variables. The variables investigated are fuel consumption, air pollution, noise, and safety. Results show that the, by far, longest route, is in fact returned as the most sustainable route option. The other two route options exhibit impacts of around double the amount of impacts yielded by the most sustainable one. The generalised sustainability cost is significantly mostly determined by the air pollution variable, due to its far-reaching spatial dispersion patterns yielding impacts even at long distances from a road.  The potential application of the inclusion of sustainability in traffic information systems are additionally reviewed, according to the behavioural mechanisms mentioned in the literature 4review. Estimations of in what contexts “most sustainable route” suggestions are potentially most likely to yield behavioural changes, are also made, and assessed. Conclusions suggest that an inclusion of “most sustainable route option” modelling into travel information systems, have the highest potential to affect route choices when the user is driving at locations previously unvisited, due to the inexistence of a status quo route in such contexts.
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Mack, S. K. "Single-route and dual-route approaches to reading aloud difficulties associated with dysphasia." Thesis, Queen Margaret University, 1999. https://eresearch.qmu.ac.uk/handle/20.500.12289/7453.

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The study of reading aloud is currently informed by two main types of theory: modular dual-route and connectionist single-route. One difference between then theories is the type of word classification system which they favour. Dual-route theory employs the regular-irregular dichotomy of classification, whereas single-route considers body neighbourhoods to be a more informative approach. This thesis explores the reading aloud performance of a group of people with dysphasia from the two theoretical standpoints by employing a specifically prepared set of real and pseudoword stimuli. As well as being classified according to regularity and body neighbourhood, all the real word stimuli were controlled for frequency. The pseudowords were divided into two groups, common pseudowords and pseudohomophones, and classified according to body neighbourhood. There were two main phases to the study. In the first phase, the stimuli were piloted and the response time performances of a group of people with dysphasia and a group of matcehd control people were compared. In the second phase, a series of tasks was developed to investigate which means of word classification best explained the visual lexical decision and reading aloud performance of people with dysphasia. The influence of word knowledge was also considered. The data was analysed both quantitatively and qualitatively. The quantitative analysis of the number of errors made indicated that classification of items by body neighbourhood and frequency provided the more comprehensive explanation of the data. Investigation of the types of errors that were made did not find a significant relationship between word type and error type, but again the results indicated that the influence of frequency and body neighbourhood was stronger than that of regularity. The findings are discussed both in terms of their implications for the two theories of reading aloud and their relevance to clinical practice.
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Peng, Zhongren. "A Simultaneous Route-level Transit Patronage Model: Demand, Supply, and Inter-route Relationship." PDXScholar, 1994. https://pdxscholar.library.pdx.edu/open_access_etds/1159.

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It is observed that transit riders are responding to service changes while transit planning is responding to ridership changes, or that transit patronage and service supply are highly interrelated. It is also noticed that transit riders transfer from route to route, the introduction of new service may draw some riders from the existing routes, which implies transit patronage on a route is also affected by other parallel and intersecting routes. An analytic tool is needed to examine these complex relationships in the transit system. This study has developed a quantitative model by incorporating these interactions into a simultaneous system. The simultaneity of transit demand, supply and the interrelationship of inter-route effects are addressed in a three-equation simultaneous model: a demand equation, a supply equation and an equation for competing routes. These equations are estimated simultaneously using the three-stage-least-squares estimation method. The model is estimated at the route-segment level by the time of a day, and by the inbound and outbound directions. Data from Portland, Oregon metropolitan area are used as an extended case study. The socioeconomic and demographic data are allocated to an one-quarter-mile distance service area around a transit route by utilizing the technique of Geographic Information Systems (GIS). The data allocation significantly reduces the measurement error. Inter-route relationships are also identified using GIS. The estimation results show that a service change on a route increases the transit patronage on that route, but it also decreases the ridership on its competing routes, so the net effect of that service improvement is smaller than the ridership increase on the subject route. A conventional single equation model under-estimates the ridership responses on the subject route, and over-estimates the net patronage response. This study is the first research to discuss the net effects of a service change at the route level. The model can be implemented for system-level policy analysis and route-level service and land use planning. It is especially useful for "what-if" scenario analysis at the route level to simulate the ridership impacts of service and land use changes.
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Dahl, Valerie, and Mikael Davidsson. "Route flow estimation based on time-dependent route choice sets and historical travel times." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-130007.

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Since congestion leads to variations in travel time which gives a variation in the traffic flow, it is interesting to estimate the traffic flow in larger cities where cars drive in a limited space. In order to estimate the traffic flow, different traffic models are usually used. These models often use volume-delay functions which calculate the travel times for each link depending on the current traffic flow. However, in these models, the process for reaching equilibrium can be time consuming and it is hard to calibrate the volume-delay functions for a road network with a large set of links. Instead, we assume that it is relatively simply to measure or collect historical time-dependent travel times on a large set of links. With this assumption, a method that uses time-dependent route choice sets and time-dependent travel times in order to estimate time-dependent route flows, is developed. In this thesis, the method was applied to Stockholm County where it is interesting to study the route choice since congestion occurs in the area which generate variations in travel time. In order to estimate time-dependent route flows, a time-sliced OD-matrix was created by dividing the matrix for the peak hour using two different time-slicing distributions. The time-dependent route choice set with time-dependent travel times was created by using an existing route planning tool. These routes were mapped to the links in a road network in order to estimate link flows. The mapping was done by using map matching and a shortest path algorithm. Route shares were decided by using a method that splits the demand equally among the routes in the route choice set for an OD-pair, and with a logit model that takes travel time into account with the assumption that the travel time can affect a traveler’s route choice. The evaluation of the resulting link flows was done by comparing these link flows with observed link flows using different time-slicing distributions and route share models. Furthermore, the method’s resulting link flows was evaluated against the resulting link flows from a scenario where all travelers are assumed to choose the shortest path, in terms of free flow travel time, between each OD-pair. The developed method can estimate link flows so that 27.9 % of the links have a GEH value less than 5, which can be compared to the commonly used acceptance criteria of 85 %. This shows that the method needs to be developed further in order to achieve link flow estimations that fulfills the acceptance criteria. Even though the overall result show that the developed method does not fulfill the acceptance criteria, the method works well on some individual links. Furthermore, the resulting link flows from the developed method match the observed link flows better than the resulting link flows from the scenario where all travelers are assumed to choose the shortest path.
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Kelly, Joseph Pierre. "Route to administrative licensure perceptions of preparation regarding traditional and examination route assistant principals /." Diss., Restricted to subscribing institutions, 2009. http://proquest.umi.com/pqdweb?did=1971755291&sid=11&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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34

Basu, Nandita. "Pedestrian route choice behaviour: Influences of built environment on route preference, safety and security." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/236797/1/Thesis_Nandita%2BBasu_24112022.pdf.

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Built environment factors influence pedestrian route choice behaviour, but their impact is not well known. This thesis investigates the influences of the built environment factors on walking route preference and safety. By using the ‘Physical Activity through Sustainable Transport Approaches’ framework, this research studied the perceptions and preferences of pedestrian route choice in a typical suburban environment in Australia through a stated preference survey. This thesis has established the interrelationship between safety, security, and built environment factors across men and women pedestrians. The findings highlight increasing land-use diversity and providing adequate trees may improve perceived safety and security among pedestrians.
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Franck, Martin, and Roos Malin Holm. "COLLISIONS IN ICE : A STUDY OF COLLISIONS INVOLVING SWEDISH ICEBREAKERS IN THE BALTIC SEA." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-25468.

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This study was conducted with the purpose of furthering the knowledge of collisionsinvolving Swedish icebreakers in the Baltic Sea. It strived to identify the causes and directeffects of this type of collision. It also sought to establish if regulations and operationalguidelines, governing Swedish icebreakers and icebreaker assistance, were sufficient and ifthey were being adhered to.The method used to accomplish this was a qualitative literature study of all data regardingSwedish icebreaker collisions from the archives of the Swedish Maritime Administration andthe Swedish Transport Agency. Several accident investigation authorities from around theworld assisted in developing a method for processing the raw data.Having processed and examined the data the prevalence of different causes contributing to thecollisions could be established. All collisions occurred during icebreaker assistance. It wasfound that the all encompassing cause of the collisions was the difficulties of evaluating theice conditions and the behavior that difficult ice conditions necessitated the vessels to adopt.It was further made clear that the direct effects for the vessels, their crew and the environmentwere of limited severity. It was also concluded that the regulations and operational guidelinesgoverning Swedish icebreaker assistance, were generally being adhered to, and weresatisfactory in enabling a sufficiently safe and effective icebreaker assistance service.
Denna studie genomfördes i syfte att utöka den akademiska kunskapen om kollisioner sominvolverar svenska isbrytare i Östersjön. Den ämnade identifiera orsakerna och de omedelbaraeffekterna av dessa kollisioner. Vidare sökte den fastslå huruvida regelverk och riktlinjer förden svenska isbrytartjänsten var tillräckliga och om de efterlevdes.Studien genomfördes som en kvalitativ litteraturstudie av all data, med anknytning tillisbrytarkollisioner, som fanns tillgänglig i Sjöfartsverkets och Transportstyrelsens arkiv. Ettflertal utländska myndigheter som utreder olyckor assisterade vid framtagandet av modellenför bearbetning av datan.Efter att ha bearbetat och undersökt datan kunde förekomsten av olika bidragande orsaker tillisbrytarkollisionerna slås fast. Alla kollisioner inträffade under isbrytarassistans. Det stodklart att den övergripande orsaken var svårigheten i att utvärdera isförhållandena och deåtgärder fartygen tvingas vidta för att kunna ta sig fram genom isen. Vidare fastslogs att deomedelbara effekterna, för såväl fartyg som besättning och miljö, inte var förödande utan avbegränsad karaktär. Det fastslogs även att de regelverk och riktlinjer som styr den svenskaisbrytarverksamheten överlag efterlevdes och var tillräckliga för att säkerställa entillfredställande säker och effektiv isbrytartjänst.
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36

Billot-Grasset, Alice. "Typologie des accidents corporels de cyclistes âgés de 10 ans et plus : un outil pour la prévention." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10025/document.

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Dans de nombreuses mégalopoles, la progression de la part modale du vélo, par ailleurs soutenue grâce à des politiques publiques, crée un intérêt grandissant pour la sécurité des cyclistes qui représente un véritable enjeu de santé publique. La plupart des études sur le sujet utilisent des données officielles issues des forces de police. Cependant ces données sous enregistrent les cyclistes et tout particulièrement les victimes d'accidents seuls. En France, une étude menée sur le Registre médical du Rhône, quasi exhaustif en termes de chutes et de collisions à vélo, a permis d'estimer qu'un cycliste a 8 fois plus de chances d'être victime d'un accident, par heure passée sur la route, qu'un automobiliste. Cette même étude identifie un sur-risque d'accident chez les femmes. Partant de ces constats, ce travail de thèse propose une image complète de l'accidentalité à vélo qui prend en compte les facteurs d'accidents identifiés dans la littérature et propose de comprendre comment le comportement du cycliste interagit avec eux. L'objectif de nos travaux est de décrire les configurations d'accident corporel pour proposer des actions en sécurité primaire ou secondaire. Pour ce faire, nous avons mené une enquête auprès de 3337 cyclistes accidentés en 2009-2011 et identifiés dans le Registre des victimes d'accidents de la circulation du Rhône. Sur la base d'un taux important de répondants, les analyses descriptives améliorent la connaissance en accidentalité cycliste, certains facteurs d'accidents étant scrutés pour la première fois par notre enquête. A la suite des différentes analyses, le rôle du sexe du cycliste dans l'accident est apparu incertain, justifiant une étude approfondie des accidents à vélo à travers le prisme du genre. Dans un ultime volet, nous proposons un ensemble de mesures et d'idées visant l'amélioration de la sécurité des déplacements cyclistes ainsi que des perspectives de recherche en accidentalité à vélo qui combleraient les lacunes du travail proposé
In many major cities, the growing modal share of cycling, mainly supported by public policies, raises the issue of cycling safety. Most of the existing work on this topic is based on police data. However, these data underreport cyclists, especially the victims of single accidents. In France, a recent study based on the Rhône road trauma registry, a medical database covering almost all cyclist falls or collisions, considers that a cyclist is 8 times more likely to be injured than a driver by hour spend on a road. The same review also reveals an increased risk of crash for women. Based on these observations, this thesis comes up with a full picture of cycling accidents, taking into account accident factors identified in the literature. The proposed work offers a better understanding on how the cyclist’s behavior interacts with them. It aims to describe accident configurations to propose preventive primary and secondary safety actions. To do so, we surveyed 3337 cyclists injured in 2009-2011 and identified in the Rhône Road Trauma Registry. Based on a significant response rate, descriptive analyses improve existing knowledge in cycling safety, some accident factors being examined for the first time in our survey. Following these analyses, gender roles were unclear, justifying an intensive investigation on cycling accidents through the prism of gender. In order to achieve this goal, we select the 44 accidents on utilitarian trips and built a logistical regression model to explain the likelihood that the victim is a woman. All factors being equal, when a injured cyclist had a load on his bike, did not know the route, fell ascending or descending a curbside, it is more likely that the victim is a woman. Conversely, the probability for the victim to be a men increases if the cyclist’s speed is one of the accident factors. These results are confirmed and illustrated analyzing textual data on accidents stories. The last part is dedicated to a proposal of a set of actions and ideas aiming at improving cycling safety. Some research perspectives are proposed to address the weaknesses of the thesis work
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Stefanius, K. (Karoliina). "Colorectal carcinogenesis via serrated route." Doctoral thesis, Oulun yliopisto, 2011. http://urn.fi/urn:isbn:9789514293993.

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Abstract Colorectal cancer is the third most common cancer in the developed countries. Originally, development of CRC was thought to proceed by a sequence of steps known as an adenoma-carcinoma sequence. At present CRC is recognized as a disease developing through diverse pathways. Serrated adenocarcinoma represents an endpoint of tumors developing from serrated pathway. This thesis focuses on studying the molecular alterations in serrated adenocarcinoma. Microsatellite instability, hypermethylation of promoter region in DNA repair genes hMLH1 and MGMT, frequency of KRAS and BRAF mutations and mutation spectrum of PTCH1 was determined in serrated adenocarcinomas (n=42) and compared to non-serrated adenocarcinomas (n=75). MSI, particularly low level of MSI (p=0.02) and methylation of both hMLH1 and MGMT promoters (p=0.004, p=0.026) were found to be more prevalent for serrated CRC. BRAF mutation was frequent and specific to serrated adenocarcinomas (p<0.001) and KRAS mutations were more frequent in serrated adenocarcinomas than in non-serrated cancers (p=0.002). A significant association between BRAF mutation, hMLH1 and MGMT methylation and MSI-H phenotype was found in serrated carcinomas. KRAS mutation was seen in association with MSS/MSI-L phenotype; in fact, if serrated adenocarcinoma presents with MSI-L there always seems to be a KRAS mutation as well. Negative immunohistochemical staining of the hMLH1 enzyme was in association with methylation of the gene and proved reliable in the detection of MSI-H phenotype (p<0.0001). Sequencing analysis of the whole coding regions of the PTCH1 gene did not reveal any truncating mutation to explain the previously detected downregulation of the gene in serrated CRCs. In conclusion, serrated adenocarcinomas proved to be an independent, but heterogeneous subtype of CRCs. High combined mutation rate (79–82%) of KRAS and BRAF in serrated adenomas and adenocarcinomas indicates that MAPK activation is a crucial part of the serrated pathway. BRAF mutations are specific for serrated adenocarcinoma, and identify a subset of serrated adenocarcinomas with gene methylation and a tendency for MSI-H. High frequency of KRAS mutations in serrated adenocarcinomas suggests that a significant proportion of KRAS-mutated CRCs originate from serrated precursors
Tiivistelmä Paksu- ja peräsuolisyöpä eli kolorektaalisyöpä on Suomessa kolmanneksi yleisin syöpätyyppi. Syöpää edeltävien muutosten tunnistaminen on tärkeää, jotta sen ehkäisy ja seuranta olisi tehokasta. Tavallisia adenoomapolyyppeja on pidetty tärkeimpinä kolorektaalisyövän esiastemuutoksina. 2000-luvulla on havaittu, että nk. sahalaitapolyypit edustavat tärkeää osaa esiastemuutoksista, ja näistä kehittyvää syöpää kutsutaan sahalaitaiseksi syöväksi. Sahalaitaisen syövän kehittymismekanismit eroavat huomattavasti tavallisesta kolorektaalisyövästä. Tässä väitöskirjassa keskityttiin tutkimaan sahalaitaiselle syövälle tyypillisiä morfologisia piirteitä sekä geneettisiä muutoksia. Työssä selvitettiin DNA mikrosatelliitti-instabiliteetin sekä DNA korjausgeenien hMLH1 ja MGMT promoottorialueiden hypermetylaation esiintyminen, nk. MAPK –signaalinsiirtoreitin komponenttien, KRAS ja BRAF -geenien, mutaatioiden yleisyys sekä PTCH1 geenin mutaatiokirjo sahalaitaisissa (n=42) ja tavallisissa kolorektaalisyövissä (n=75). DNA:n mikrosatelliitti-instabiliteetti, erityisesti matala-asteisena (MSI-L) (p=0.02) sekä MLH1 ja hMGMT -geenien metylaatio (p=0.004, p=0.026) olivat yleisempiä sahalaitaisissa syövissä. BRAF mutaatio oli yleinen sekä spesifinen sahalaitasyöville (p<0.001). Myös KRAS -mutaatiot olivat yleisempiä sahalaitaisissa syövissä (p=0.002). BRAF mutaatio, hMLH1 sekä MGMT metylaatio ja korkea-asteinen mikrosatelliitti-instabiliteetti (MSI-H) esiintyivät hyvin usein yhdessä sahalaitaisissa syövissä. Sahalaitaisissa syövissä KRAS –mutaatiot liittyivät MSI-L fenotyyppiin. hMLH1 geenin ilmentyminen tutkittiin myös immunohistokemiallisesti. Sahalaitaisissa syövissä MLH1 –proteiinin häviäiminen oli yhteydessä metylaatioon ja liittyi spesifisesti MSI-H:n esiintymiseen (p < 0.0001). PTCH1 geenin sekvensointi ei paljastanut proteiinin toimintaa vahingoittavia muutoksia, eikä tuloksen perusteella pystytä selittämään aikaisemmin havaittua geenin ilmentymisen häviämistä sahalaitaisessa syövässä. Tulosten perusteella sahalaitainen syöpä on oma, mutta heterogeeninen kolorektaalisyövän alatyyppi. KRAS ja BRAF –geenien aktivoivien mutaatioiden yleisyys (79–82%) osoittaa, että MAPK -reitin aktivaatio on tärkeää sahalaitaisen syövän kehityksessä. BRAF -mutaatiot ovat spesifisiä sahalaitaisille syöville, ja yhdessä metylaation sekä MSI-H:n kanssa identifioi osan sahalaitasyövistä omaksi ryhmäkseen. KRAS –mutaatioiden yleisyys sahalaitaisissa syövissä antaa aiheen epäillä, että merkittävä osa KRAS –mutaation sisältävistä kolorektaalisyövistä kehittyy sahalaitapolyypeista
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38

Weetman, John. "A new route to oligonucleotides." Thesis, University of Leicester, 1985. http://hdl.handle.net/2381/33983.

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The application of the Arbusov reaction to generate a nucleoside-containing phosphoryl halide for use in oligonucleotide synthesis has been investigated. In Arbusov reactions on mixed trialkyl phosphites, t-butyl halide is always lost in preference to methyl, ethyl or cyclo-pentyl halide. Exploitation of this apparent SNI nature of the second stage of the reaction was proposed. The phosphitylating agent t-butyl methyl phosphorochloridite was found not to be isolable and t-butyl methyl N, N-dimethyl phosphoramidite upon phosphitylation of a 5'-protected monomer using tetrazole as acid catalyst was prone to loss of isobutylene The use of alternative groupings, namely, 2-methoxyethyl, 1-methoxypropan 2-yl, allyl, 1-methoxy-2-methyl propan-2-yl and 1-methylcyclopentyl to exploit the SNI nature of the reaction proved unsuccessful. Dimethyl phosphorochloridite was found to phosphitylate a 5'- protected monomer efficiently. Reaction with bromine proceeded with exclusive loss of methyl bromide. SN2 attack at methyl is thought to occur preferentially since bromide ion is sterically prevented from attacking the 3'-position by the nucleobase and the bulky trityl protecting group. The resulting phosphorobromidates were found to phosphorylate the 5'-hydroxyl of a 3'-protected monomer efficiently in solution in the presence of l-methylimidazole. DMF, DMPU, pyridine and tetrazole have also been investigated as activating agents. Using o-chlorophenyl as the internucleotide protecting group this procedure was unsuccessful but this led to a series of interesting acid catalysed ligand exchange reactions on aryl diethyl phosphites containing various substituted aryl groups, those with the most electron-withdrawing substituents generally exchanging most rapidly. The route beginning from dimethyl phosphorochloridite was investigated on a CPG polymer support. A thymidine residue bearing an acid labile 5'-0-protecting group and attached through its 3'-position via a succinate linkage and a LCAA spacer to the polymer support was deprotected with trichloroacetic acid. Subsequent phosphorylation of the free 5'-hydroxyl was found to be inefficient, the reason suggested being that the longer phosphorylation reaction times required on the solid support allowed demethylation of the active phosphorylating agent by halide ion to occur.
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39

Zhang, Xiaohui. "A cycloaddition route to pyrrolidines." Thesis, Open University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439241.

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40

Farver, Jennifer M. (Jennifer Margaret) 1976. "Hybrid vehicle-centric route guidance." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33689.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2005.
Includes bibliographical references (p. 223-228).
This thesis proposes a hybrid route guidance system in which predictive guidance is generated in a centralized layer and revised in a reactive, decentralized layer that resides on-board the vehicle. This hybrid approach is intended to improve guidance quality by balancing the ability of the centralized layer to generate consistent guidance with the ability of the decentralized layer to respond rapidly to incidents. Centralized guidance is computed using a rolling-horizon Dynamic Traffic Assignment routine based on the Method of Successive Averages. This guidance is disseminated to equipped vehicles in the form of prescribed paths, which may be subsequently revised by an on-board decentralized layer. This decentralized layer revises only the local portion of the vehicle's path in order to limit the potential negative impact of its myopic reactive algorithm. The layer uses a simple splitting algorithm in order to heuristically balance demand on alternate paths. Both layers utilize data collected by guided vehicles. The centralized layer uses position data from guided vehicles. The decentralized layer uses local arc travel time data which is shared among guided vehicles.
(cont.) This approach follows the vision of a vehicle-centric route guidance system whose design is focused on the vehicle, rather than on stationary components. In order to test the performance of the proposed system, a small test network is simulated in a simple network simulator. The primary experimental questions are: whether the hybrid system provides higher quality route guidance than either a fully centralized or fully decentralized system; and how hybrid guidance quality is affected by various parameters of the system and the testing environment. Results of testing confirm that the hybrid system provides higher quality guidance than either centralized or decentralized systems in most scenarios; in no scenario is the hybrid system found to perform measurably worse than the centralized or decentralized system. The greatest benefits of the hybrid system are found to be in incident scenarios, supporting the hypothesis that the decentralized layer may aid incident response.
by Jennifer Margaret Farver.
Ph.D.
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41

Ramming, Michael Scott. "Network knowledge and route choice." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/49797.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2002.
Includes bibliographical references (p. 225-236).
Models of urban traveler route choice are reviewed in the context of Intelligent Transportation Systems, particularly Advanced Traveler Information S ystems. Existing models suffer from assumptions of perfect information about travel conditions a nd infinite information processing capabilities of drivers. We present evidence that a majority of travelers fail to minimize travel time or distance. We also show that travelers with more network knowledge appear to vary their commute route to respond to changing travel conditions. Coefficient estimates of a model of network knowledge, based on the geographical idea of spatial ability, are presented. To better understand habitual route choice behavior, we examine many possible route generation algorithms. A simulation approach is preferred because it allows for heterogeneity in driver perceptions and it has a quick computational time. Alternative route choice model specifications such as Multinomial Logit, C-Logit, Path Size Logit, Cross-Nested Logit and Logit Kernel Probit are evaluated. The exponential specification of the Path S ize term, using a large parameter value, offers a considerable improvement in fit over MNL, C -Logit and CNL. A hybrid Path Size Logit and Logit Kernel Probit model offers the best overall fit; however, the stability of these estimates requires further examination. The hybrid Path S ize Logit and CNL model provides the next best empirical fit. Random coefficient specifications of MNL, PS L and LK Probit models were also examined.
Significant random coefficient parameter estimates were only obtained for the MNL model. This result suggests that random coefficients capture variation in route choice models that would be more effectively explained by a Path S ize or LK Probit specification. Model fit can be further improved by adding an Implicit Availability/Perception term that includes estimated network knowledge. However, this term provides limited explanatory power, as can be seen by its standard errors and by forecasts that are relatively insensitive to changes in traveler knowledge. These results suggest that continued development of better attitudinal surveys to assess network knowledge and wayfinding strategies would allow estimation of route choice models with better explanatory power.
by Michael Scott Ramming.
Ph.D.
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42

Doyle, Kevin James. "Rhodium carbenoid route to oxazoles." Thesis, Loughborough University, 1994. https://dspace.lboro.ac.uk/2134/33073.

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This thesis describes investigations by the author into the preparation of the oxazole heterocyclic system, by the use of rhodium carbenoid methodology. Chapter 1 is a review of the literature on the formation of oxazoles, by the reaction between diazocarbonyl compounds and nitrites. The various conditions that have been employed in the reaction are detailed, as well as developments into the understanding of its mechanism. Chapter 2 reports the study into the preparation of 4-functionalised oxazoles. A series of 4- benzenesulfonyloxazoles, oxazole-4-phosphates and oxazole-4-carbonitriles were prepared by a rhodium(II)-catalysed reaction. The effect of varying the rhodium(II) catalyst on oxazole formation is detailed. The oxazole-4-carbonitrile methodology was extended to form bis-oxazoles. Attempts to extend this chemisiry towards tris-oxazoles is discussed. Chapter 3 describes the synthesis of the oxazolylindole alkaloids pimprinine, pimprinethine and WS-30581A. This was achieved by the reaction of tert-butyl 3-diazoacetylindole-1- carboxylate with the appropriate nitrile, under rhodium(II) catalysis, followed by deprotection. Studies into varying the substituents at the 2- and 4-positions of the oxazole ring is described. Chapter 4 relates investigations into the synthesis of the cytotoxic cyclic peptides, diazonamide A and B, isolated from the ascidian, Diazona chinensis. These investigations were centred on key skeletal features: an oxazolylindole moiety, an oxazole based around (S)-valine and a functionalised benzofuranol. Model studies towards the oxazolylindole and the valine oxazole sections were undertaken, utilising rhodium carbenoid methodology to prepare the azote heterocycle. Formation of the benzofuranol model involved a one step deprotection and cyclisation, the precursor being prepared via a Claisen rearrangement and an ozonolysis. Chapter 5 contains the experimental data, whilst Chapter 6 contains the references.
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43

Wu, Ling Ling. "Contribution à la route automatisée." Marne-la-vallée, ENPC, 1999. http://www.theses.fr/1999ENPCA001.

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44

Schultes, Dominik. "Route planning in road networks." [S.l. : s.n.], 2008. http://digbib.ubka.uni-karlsruhe.de/volltexte/1000007755.

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45

Guo, Xialing. "Syntheses en route to morphine /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1997. http://wwwlib.umi.com/cr/ucsd/fullcit?p9726904.

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46

Loreau, Tanguy. "Construction automatique de modèles multi-corps de substitution aux simulations de crashtests." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLC082/document.

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Chez Renault, pour réaliser les études amont, les équipes en charge de la prestation du choc automobile disposent de modèles très simples leur permettant de pré-dimensionner le véhicule. Aujourd'hui, ils sont construits à partir du comportement d'un ou quelques véhicules de référence. Ils sont fonctionnels et permettent le dimensionnement. Mais à présent, l'entreprise souhaite construire ses modèles amont en s'appuyant sur l'ensemble de ses véhicules. En d'autres termes, elle souhaite disposer d'une méthode d'analyse automatique de simulations de crashtests afin de capitaliser leurs résultats dans une base de données de modèles simplifiés.Pour répondre à cet objectif, nous développons une méthode permettant d'extraire des simulations de crashtests les données nécessaires à la construction d'un modèle multi-corps de substitution : CrashScan. Le processus d'analyse implémenté dans CrashScan se résume en trois étapes majeures.La première consiste à identifier l'ensemble des zones peu déformées sur une simulation de crashtest. Cela nous permet de dresser le graphe topologique du futur modèle de substitution. La seconde étape est une analyse des cinématiques relatives entre les portions peu déformées : les directions principales et les modes de déformation (e.g. compression, flexion) sont identifiés en analysant le mouvement relatif. La dernière étape consiste à analyser les efforts et les moments situés entre les zones peu déformées dans les repères associés aux directions principales des déformations en fonction des déformations. Cela nous permet d'identifier des modèles hystérétiques de Bouc-Wen équivalents. Ces modèles disposent de trois paramètres utiles dans notre cas : une raideur, un effort seuil avant plastification et une pente d'écrouissage. Ces paramètres peuvent être utilisés directement par les experts des études amont.Enfin, nous construisons les modèles multi-corps de substitution pour trois cas d'étude différents. Nous les comparons alors à leur référence sur les résultats qu'ils fournissent pour les critères utilisés en amont : les modèles générés par CrashScan semblent apporter la précision et la fidélité nécessaires pour être utilisés en amont du développement automobile.Pour poursuivre ces travaux de recherche et aboutir à une solution industrielle, il reste néanmoins des verrous à lever dont les principaux sont la synthèse d'un mouvement quelconque en six mouvements élémentaires et la synthèse multi-corps sur des éléments autres que des poutres
At Renault, to fulfill upstream studies, teams in charge of crashworthiness use very simple models to pre-size the vehicle. Today, these models are built from the physical behavior of only one or some reference vehicles. They work and allow to size the project. But today, the company wishes to build its upstream models using all its vehicles. In other words, it wishes to get an automatic method to analyze crashtests simulations to capitalize their results in a database of simplified models.To meet this goal, we decide to use the multi-body model theory. We develop a method to analyze crashtests simulations in order to extract the data required to build a surrogate multi-body model : CrashScan. The analysis process implemented in CrashScan can be split into three major steps.The first one allows to identify the low deformed zones on a crashtest simulation. Then, we can build the topological graph of the future surrogate model. The second step is to analyze the relative kinematics between the low deformed zones : major directions and deformation modes (e.g. crushing or bending) are identified analysing relative movements. The last step is to analyze strengths and moments located between the low deformed zones, viewed in the frames associated to the major directions of deformations in function of the deformations. This allows us to identify equivalent Bouc-Wen hysteretic models. These models have three parameters that we can use : a stiffness, a threshold strength before plastification and a strain of hardening. These parameters can directly be used by upstream studies experts.Finally, we build multi-body models for three different use case. We compare them to their reference over the results they produce for the upstream criteria : models generated with CrashScan seems to grant the precision and the fidelity required to be used during automotive development's upstream phases.To continue this research work and get an industrial solution, there are still some locks to lift, the main ones are : synthesis of any movement into six elementary ones and multi-body synthesis on elements other than beams
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47

Schönning, Karin. "Meson production in pd collisions." Doctoral thesis, Uppsala universitet, Kärn- och partikelfysik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-100786.

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Meson production in proton-deuteron collisions has been studied using the WASA detector facility at the CELSIUS storage ring in Uppsala. Data were obtained at two different beam energies, 1360 MeV and 1450 MeV, slightly above threshold for η and ω mesons. The differential cross sections of pd → 3He ω constitute the first measurements of this reaction covering the whole angular range. The ω angular distributions are isotropic at 1360 MeV but have strong forward and backward enhancements at 1450 MeV. Theoretical calculations using a two-step model fail to reproduce the shapes of the angular distributions and underestimate the total cross sections. The tensor polarisation of the ω meson has been derived from the measured angular distributions of the ω decay products. The π+ π- π0 and the π0 γ decay channels gave consistent results, showing that the ω meson is produced unpolarised at both energies. This is in contrast to a recent MOMO measurement which showed that the Φ meson is produced almost completely polarised in the pd → 3HeΦ reaction. Different production dynamics of ω and Φ mesons close to threshold raises the question whether the Okubo-Zweig-Iizuka (OZI) rule is applicable in low-energy nucleon-nucleon reactions. The angular distributions of the η meson produced in the pd → 3He η reaction are strongly enhanced for forward going η mesons at both energies. The σ(pd → 3He π+ π- π0 )/σ(pd → 3He π0 π0 π0 ) ratio has been measured and discussed in terms of isospin amplitudes. A rough estimate of the pd → 3He π0 π0 π0 π0 cross sections has also been obtained and the pd → 3He η π0 reaction has been studied for the first time near threshold.
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48

Diehl, Markus. "Diffraction in electron-proton collisions." Thesis, University of Cambridge, 1996. https://www.repository.cam.ac.uk/handle/1810/265482.

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Subject of this thesis is diffractive collisions of electrons and protons, i.e. collisions wher~ the proton remains intact or is slightly excited, and loses only a small fraction of its initial energy. Such processes can be described by the exchange of a pomeron, which is well-known from the phenomenology of highenergy hadron scattering but far from being understood in the framework of quantum chromodynamics. We use the simple model of Landshoff and Nachtmann, where the pomeron is approximated by two nonperturbative gluons, to calculate the cross section for diffractive production of a quark-antiquark pair from a real or virtual photon. This allows us to give detailed predictions for diffractive electro- or photoproduction of a jet pair, for diffractive charm production, and for the inclusive cross section in diffractive deep inelastic scattering at not too large masses of the diffractive system. For the latter we find rather good agreement with the data taken at the HERA collider, taking into account the uncertainties of our calculation. We then turn our attention to azimuthal correlations in diffractive scattering. The dependence of the electron-proton cross section on the angle between the lepton plane and some direction in the hadronic final state has a simple relation with cross sections and interference terms of the photon-proton subprocess for definite photon helicity. Its measurement can be used to constrain the cross section for longitudinally polarised photons. We compute the distribution of the azimuthal jet angle in diffractive dijet production in the Landshoff-Nachtmann model and find that useful bounds on the longitudinal cross section for such events might be obtained from its measurement. Going further we extend our calculation of quark-antiquark production to finite squared momentum transfer from the proton. This enables us to investigate the distribution of another important azimuthal angle, that of the scattered proton, which contains information about the helicity of the pomeron. The last part of this thesis is devoted to the phenomenological pomeron model of Donnachie and Landshoff. When applied to diffractive quark-antiquark production it violates electromagnetic gauge invariance. We suggest a prescription to deal with this problem and compare the results we then obtain with those of the Landshoff-Nachtmann model. We find remarkable similarities between the two models, but they also show important differences, especially in details of kinematical distributions.
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49

Nagy, Jozsef Bordas. "Kilovolt collisions of small ions." Thesis, University of Ottawa (Canada), 1989. http://hdl.handle.net/10393/21086.

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50

O'Rouke, Sheelagh Francesca Camille. "Theory of ion-atom collisions." Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334486.

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