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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
391

Trend Analysis of Automobile Collision Amongst 15-19 year olds in Virginia, 2000-2004

Ndem, Imo F. 01 January 2007 (has links)
Purpose. This research study on automobile collision in Virginia amongst fifteen to nineteen (15-19) year olds looked into the trend analysis over a five (5) year period of 2000 to 2004. Trend analysis is usually done for aggregates of all injuries—either intentional or unintentional injuries, or both. The primary objective of this research study was to examine the trend in hospitalization rates and mortality rates for males and females independently. It further looked into the trend, if any, in hospitalization rates, mortality rates, and case-fatality rates, for both males and females combined. The different Tables illustrate the extent and the impact of automobile collision in terms of demographics and characteristics of hospitalizations, types of hospitalizations, hospitalization rates, mortality rates and case-fatality rates among this age group.Methods: An investigation was carried out in a case control manner of 2353 cases using data from the Virginia Department of Health-Division of Injury Prevention & Violence on automobile collision amongst 15-19 year olds, from 2000 to 2004, a (5) five year period. Hospitalization data were obtained from Virginia Health Information, coded in line with International Classification of Diseases, 9th revision (ICD-9); external cause of injury (E)-codes. Mortalityldeath rates and case fatality rates were calculated using U.S. Census Bureau, Census 2000 for Virginia's population data. Frequency distribution analysis was done with SPSS 14.0, data entry using M.S. Excel, while rate ratio and confidence intervals for hospitalization rates, mortality rates were calculated. Linear trend was analyzed for hospitalization rates, mortality rates and case-fatality rates, using Chi square statistics test for significance. Geographical Information System (GIs) methods were used to display counties in Virginia.Results: Out of 2353 cases of automobile collision in Virginia, amongst 15-19 year olds, from 2000 to 2004, the demographic did not changed much. Males were fairly distributed over the five year period, while automobile collision characteristics showed that 2142 cases (91%) were more likely to be hospitalized on an emergency basis, with males having a higher percentage, fifty-nine (59%) percent, and forty (40%)percent for females. (Table 1 & 2). The hospitalization rates were higher for males than females, with rate ratio (RR>1) greater than one over the five years of study (Table 3). Mortality rates showed increase rates for males, over the five year of study (RR>1.5) (Table 4). Test for linear trend in hospitalization rates (Chi. Sq.=14.127, p-value ≤ 0.001) were significant for both males and females. Mortality rates test for trend were also significant for both males and females. (Chi Sq. = 377.0, p-value ≤ 0.001). Case-fatality rates trend test were significant for both males and females. (Chi sq. = 11.580, p value ≤ 0.001). The trend in hospitalization, mortality and case-fatality rates, showed a decrease over the five year of study.Conclusion: Given the impact of injuries in ,the U.S., mainly automobile collisions, it is socially beneficial to continue research, intervention and prevention programs in this area, particularly directed and targeted to this population - Healthy People 2010 objectives.
392

Dopravní chování obyvatel obcí zázemí Prahy / Travel Behaviour of the Prague Suburb Population

Pergl, Ondřej January 2012 (has links)
Travel behavior of Prague suburb population Abstract The hinterland of Prague is formed by the process of suburbanization, which influences the spatial structure of whole region. Changed spatial structure puts greater demand on the mobility of the population. The main aim of this work is the research of travel behavior of the Prague suburb population, who makes his movements primarily by the car. The work focuses on the factors influencing travel behavior, which are discussed in theoretical section. The next section discusses the measures against individual transport. The empirical part presents the results of survey in Prague southeast hinterland. Travel behavior is examined in terms of modal split and trip purpose. Further investagation is focused on citizens' satisfaction with the traffic situation in their municipality and reveals their sensitivity to various measures against car use. Key words: mobility, travel behavior, suburbanization, car use limiting, Prague
393

Bydlení v okolí pražské severo-jižní magistrály. Život v sousedství městské dopravní tepny - empirická sonda / Housing around the north-south arterial road in Prague. Living nearby the city's thoroughfare - empiric study

Vlasáková, Tereza January 2013 (has links)
The thesis is conceived as an empirical probe into the life of the local residents around the north-south artery in the district of Prague 4. Thematically falls within the urban sociology and is also greatly inspired by the field of urbanism and urban planning. The goal is to obtain and bring out basic information about the quality of housing and urban life around the given section of Prague's north-south highway perceived through the eyes of the population. The first part constitutes theoretical background of the empiric survey. It specifies a relation of branch disciplines to the selected topic and outlines the theoretical concepts associated with the main aspects of this problem. The second part presents conducted empirical probe, gives a summary and comments on results of the analysis. Data collection was carried out using a questionnaire survey in the locality. The processing by quantitative techniques were used for data analysis
394

Estimation de pose de grands blocs d'images panoramiques issues de systèmes de numérisation mobile / Pose estimation on large block of panoramic images from mobile mapping systems

Cannelle, Bertrand 04 December 2013 (has links)
Tirée par le développement et la démocratisation des globes numériques et des systèmes de géolocalisation grand public, la numérisation 3D mobile terrestre en milieux urbains s'est développée de manière très importante ces dix dernières années. Les principaux verrous résiduels de ces systèmes reste d'une part la localisation précise des données pour certaines applications (conduite autonome urbaine, levers de géomètres, etc.) du fait des masques et multi-trajets GPS dans les canyons urbains et d'autre part le passage à l'échelle du traitement de l'information vu les volumes de données considérables acquis chaque jour (plusieurs To).La première partie de cette thèse est consacrée à la présentation de la numérisation mobile, aussi bien du point de vue système que du point de vue usage. Une description fine du système Stéréopolis V2, véhicule de numérisation mobile multi-caméras développée au laboratoire MATIS de l'Institut National de l'Information Géographique et Forestière, est faite afin de présenter les données utilisées dans cette thèse. Les blocs d'images manipulés dans ces travaux sont constitués de plusieurs centaines de milliers à un million d'image. La seconde partie est consacrée à la calibration du système: calibration intrinsèque de caméra, tout d'abord, en utilisant une géométrie d'acquisition de type panoramique, qui permet de s'affranchir de réseaux de cibles 3D métrologiques. Une calibration extrinsèque des imageurs du véhicule, ensuite, qui permet de déterminer de façon précise la position et l'orientation de caméras sur un dispositif de numérisation mobile. Deux procédures sont détaillées et comparées: l'une dite "off-line" nécessitant une acquisition spécifique avec un réseau de cibles métrologiques et l'autre dite "on-line" utilisant uniquement les données d'acquisition standards. Nous démontrons que la méthode "on-line" produit dans les mêmes conditions une précision comparable à celle "off-line" tout en étant plus adaptée aux variations de conditions d'acquisition in-situ. La troisième partie détaille le processus de compensation par faisceaux appliquée aux données de numérisation mobile multi-caméras qui permet d'estimer la pose d'un grand nombre d'images. La mise en équation ainsi que différents cas d'utilisations de la méthode sont explicités. La structuration et la gestion des données dans un entrepôt est elle aussi développée car elle permet la gestion d'importants volumes et donc le passage à l'échelle tout en restant performante. La quatrième et dernière partie propose différentes méthodes de recalage qui peuvent être utilisées aussi bien de manière individuelle que combinées afin de permettre de mettre en cohérence des séquences d'images distinctes (boucles, passage multi-dates, etc.) dans des contextes applicatifs différents / Mobile mapping technology has grown exponentially the last ten years, particularly due to advances in computer and sensor performances. However, the very accurate positioning of data generated by such technique remains a crucial issue. The first part of this thesis presents the mobile mapping system that has been designed in the MATIS lab of IGN as well as its operational use. A detailed analysis of image data is proposed and data used for this work is discussed. The second part tackles the standard calibration procedure. First, camera calibration is performed by using a panoramic-based acquisition geometry, which allows not to required ground control points. Secondly, a full calibration procedure dedicated to the Stéréopolis V2is proposed so as to determine accurately the position and orientation of all the cameras. For that purpose, two procedures are explained : one requiring an area with points positioned with high accuracy ,and the other one based only the data acquisition. The third section details the compensation applied to the mobile mapping car that allows to improve poses of a large number of images. The mathematical formulation is proposed, and various cases of the method are explained. Data management is also presented since it is a mandatory step for efficient large amount of data management The fourth and final part of the thesis presents different registration scenarii, where methods developed in this work can be used individually as well as combined with other ones so as to bring higher coherence between sequences of distinct images
395

Návrh designu vozu Mitsuoka Kit Car / Mitsuoka Kit Car Design

Kratochvíl, Jaroslav January 2011 (has links)
A dissertation deals with small single-placed car body design (so-called microcar cathegory). The new design is based on the undercart and the engine of serial Mitsuoka Kit Car. Therefore the aim belongs to re-design tasks. Analytical part of the dissertation deals with two basic questions influencing the final draft. The Corporate identity at first and a problematic of the target group level of aesthetical perception linked to preferred design. On grounds of analysis the core values for new design have been set down. The particular values have been presented with the help of existing reference objects from the field of automotive design. This part also includes a questionnairy, which had been focused on prefered design conception. Due to low microcars topic awareness in Czech Republic, the questionnairy had informational character and the final design conception has been chosen on the base of functional aspects analysis. The final design development, shown on sketches and basic software renderings, is based on gradual steps that lead to the core values expression with regards to input parameters and basic design rules as well. The final design is introduced together with description of its technical solution and detailed design. The solution respects the mentioned target group and the institution Corporate Identity.
396

Hot spot analýza krádeží automobilů v Liberci / Hot spot analysis of car thefts in Liberec

Kostka, Jiří January 2016 (has links)
My diploma thesis deals with distribution analysis of car thefts in the town of Liberec and will look at the options of situational crime prevention techniques. In my diploma thesis I have used the concept of hot spots which is able to show higher than average concentrations of car thefts in the study area. The database is relatively unique, provided by the regional police department in Liberec and contains the records of more than a thousand reported car thefts in Liberec between the years 2011-2014. The provided data contains GPS coordinates and thanks to them, it was possible, with relatively high accuracy, to identify hot spots of car thefts in Liberec. The identification of hot spots was possible as spatial statistics were used that enabled concrete calculations of kernel density, which made it possible to identify problem locations. In our chosen hot spots we then undertook our fieldwork, whose main goal was to evaluate the options of utilization strategy CPTED, so as to obtain preventive measures in problem locations. The output of this thesis include hot spot maps of car thefts 2011-2014 and also recommendations for preventive measures, which would be advisable to implement in chosen hot spots. Key words: car thefts, crime mapping, CPTED, hot spot, crime prevention, GIS
397

L'amélioration de l'habitabilité automobile de demain : l'application des principes de la construction architecturale de la maison dans la conception de l'habitacle des concepts-cars / Improvement of tomorrow's automobile habitability : application of the habitat architectural construction principles in the design of the automobile's cabin

Khoudeir, Riad 11 January 2007 (has links)
Notre recherche s’inscrit dans le domaine du génie industriel. Elle porte sur l’amélioration de l’habitabilité de l’habitacle de l’automobile de demain. Cette étude met en évidence l’influence de la conception de l’habitat sur la conception de l’habitacle de l’automobile. L’objectif de ce travail est de proposer un outil destiné à aider le concepteur de l’automobile à introduire les principes de la construction architecturale de l’habitat dans la conception de l’habitacle de l’automobile pour améliorer son habitabilité. Dans notre démarche expérimentale nous avons adopté des principes de la méthode d’analyse des tendances conjointe comme les mappings et les planches de catégorisation. Cette démarche montre que les concepteurs de l’automobile ont orienté leur démarche vers l’intégration de plus en plus de principes de la construction architecturale de l’habitat dans la conception de l’habitacle des concept-cars. L’enquête que nous avons effectuée auprès des architectes et des designers nous a confirmé que l’habitat et l’automobile partagent les mêmes critères de l’habitabilité. Aussi, elle nous a affirmé l’impact positif des principes de la construction architecturale de l’habitat sur l’amélioration des critères de l’habitabilité dans l’espace de l’habitacle automobile. Notre recherche ouvre des perspectives pour analyser l’impact des autres secteurs d’influence comme l’aéronautique et l’électronique sur la conception de l’automobile. Aussi, elle montre l’importance de l’analyse de l’impact de la conception de l’automobile sur la conception de l’habitat du futur. / The research field of this work is Industrial Engineering. This paper presents a study made to improve tomorrow’s automobile cabin habitability. It is focused on showing the influence on car-interior design by today’s home-interior design. The objective of this work is to propose a tool intended to help automobile designers to introduce home architectural construction principles into the car’s cabin design to improve its habitability. In our experimental phase we adopted principles of the method of analysis of the joint tendencies such as mappings and boards of categorization. This step showed that car designers have been increasingly using the home architectural construction principles on the car’s cabin conception design. Our research took into account the opinion of experts in both areas: architecture and design. In this way, we can be certain that the home and the automobile share the same criteria of habitability. We could also confirm that home architectural principles have a positive impact on the improvement of the habitability criteria in space design of the automobile’s cabin. This work opens a research line to analyze the influence of different areas in automobile design, such as aeronautics and electronics. This study can also show the inverse perspective of how car design can eventually have an impact on the future home design.
398

Stakeholder values of car parking

Beetham, Isobel F. January 2015 (has links)
Widespread car usage of around 800 million of cars travelling 30 billion of kilometres on a daily basis has led to many benefits but also to significant environmental and societal impacts such as congestion, air and noise pollution and urban sprawl. This thesis aims to investigate the stakeholder values of car parking in order to support and inform the decision makers who are tasked with how best to resolve challenging car parking dilemmas. A two phase progressive methodology is involved. Phase one begins with conducting a series of in-depth semi-structured interviews with eight academics to identify whom the stakeholders are that are affected by car parking. Then a second series of 20 interviews are conducted with sector leaders of stakeholder groups to establish how the stakeholders are affected by car parking and importantly, how they value car parking. Finally a third series of nine interviews are conducted with nine different experts to help to bridge the gap between phase one and phase two. Phase one found that a broader reach of stakeholders (classified into four different groups) are affected by car parking than the literature might imply, and that they value car parking in eight different key ways. It also found that the values emerged from a context of governmental, social and consumer concerns. Phase two of the methodology was quantitative and used the findings from phase one to develop four additional attributes considered meaningful across all four stakeholder groups, namely: safety, politics, public spaces and weekly household council tax. Choice based conjoint analysis was used to incorporate the attributes into three hypothetical scenarios namely; driver, strategy and social, as these were considered to be reflective of the value context unearthed previously in phase one. The scenarios were disseminated across England as part of a wider survey and achieved a sample size of 1107 responses. The results of which were then interpreted through willingness to pay (WTP) values. Key findings included: how a persistent political undertone can impact on car parking policy setting; that the car parking industry is under pressure to provide a service chiefly motivated by a perceived consumer intolerance of market prices; and that stakeholders can not only appreciate but also experience the impact of car parking choices on other stakeholder groups. Conclusions drawn included that the different stakeholder groups took issue with national government leadership believing it to currently be deficient in setting the standards for British car parking. Moreover, decision makers wrongly perceive that consumers of car parking do not pass between the groups and are therefore hostile to policies which do not directly benefit them. The key implication being that decision makers are cautious to implement policies which are not necessarily advantageous to consumers but which may lead to gains for the remaining stakeholder groups. In short, this thesis recommends amongst others that the governmental stakeholder group should seek to provide direction and guidelines for tariff setting which is reflective of the provision of a service that is conscious of the range of parking industry stakeholder values. Furthermore, as safety is an industry held value, practitioners should seek to better understand how it impacts their market. They should explore the relevance of schemes such as Park Mark to operators and their customers, by fundamentally investigating to what extent safety exists as a valid concern inside car parks and how it applies to personal safety, vehicle safety or general perceptions of safety. In addition, where the governmental stakeholder group remain mindful of the significance of securing political backing, the car parking industry would benefit from appreciating the sensitivities of political challenges faced by the governmental group when lobbying for any changes in parking policy programmes. Indeed, the parking industry should collaborate between the two parties and seek to unite in finding agreeable solutions which benefit constituents either directly or indirectly. As car parking values might differ according to their geopolitical context and lead to the extraction of a different set of attributes, further work would include looking beyond England to first the UK and then to abroad to explore the effects of potential cultural differences and learn the relevant lessons.
399

Hur ser framtiden ut för bilindustrin och hur väl är Volvo Cars redo för framtiden? : En djupdykning i bilindustrins framtida utmaningar utifrån ett forsknings- och utvecklingsperspektiv

Matsson, Cecilia, Johansson, Matilda January 2016 (has links)
Background: The global car industry is going through a process of change where the traditional car companies are being challenged. It is essential for those companies to keep up with the changing market conditions and invest in research and development, if they want to remain competitive in the future market. Volvo Cars is a prominent car manufacturer in Sweden, but is small globally. It was, therefore, adjudged as an interesting company to research with respect to how they address the aforementioned challenges.  Purpose: With an understanding and focus on the car industry’s new challenges, the purpose of this study is to investigate and illustrate Volvo Cars’ future prospective on the global car market. Method: The study has combined quantitative and qualitative approaches, viewed from an inductive perspective. Qualitative interviews were performed to obtain a deeper understanding of the car industry’s challenges, and data from secondary sources were collected in order to quantify Volvo Cars’ performance relative to other car companies. Result: The study determined the main challenges for the future of the personal vehicle sector to be: automation, environment, changing customer demand and digitalization. In addition to the innovation-based challenges mentioned above, the expanding Chinese market has been identified as a challenge for car companies to capitalise on. The expansion of the Chinese market is due to the rapidly increasing middle class, combined with a low car density. The idea that China (and the rest of Asia) will become an important future market is supported by the opinions of many experts and interview respondents who believe that car density in the western world will decline which means strengthen the importance of China as a future market. Volvo Cars face the same challenges as other car manufacturers. However, given their small global significance, Volvo Cars will need to focus and appropriately allocate their resources on only one or two challenges. In terms of investing in research and development, Volvo Cars is at the forefront, with a significant portion of their revenue being dedicated to the area. Conclusion: Given Volvo Cars’ small global significance, they will not have the ability to focus on all challenges. Instead, they must focus their research and development on a select few areas to be able to compete in the future automotive market. This study has identified three major challenges for Volvo Cars: to successfully grow in China (as well as in the rest of Asia), to increase total sales and market share, and to advance within automation and electrical operation. Given that Volvo Cars continue increasing their sales, especially in China, while simultaneously investing in research and development aimed at automation and electric drive, the researchers believe that the future of Volvo Cars is very promising. / Bakgrund: Bilindustrin går igenom en förändringsprocess och de traditionella biltillverkarna står inför stora utmaningar. I och med detta är det viktigt för bilföretagen att hänga med i processen och investera i forskning och utveckling, om de vill konkurrera om framtida marknadsandelar. Volvo Cars är en ledande aktör på den svenska marknaden samtidigt som de är små på den globala marknaden, vilket väcker ett intresse hos forskarna att studera företaget med avseende på hur det kommer att hantera dessa framtida utmaningar. Syfte: Syftet är att med utgångspunkt från bilindustrins nya utmaningar undersöka och belysa Volvo Cars framtidsutsikter på den globala bilmarknaden. Metod: Studien bygger på en kombination av kvalitativ och kvantitativ forskningsstrategi med ett induktivt angreppsätt. Kvalitativa intervjuer har genomförts för få en djupare förståelse för bilindustrins utmaningar och sekundärdata har samlats in för att på ett kvantitativt sätt visa hur Volvo Cars förhåller sig gentemot andra bilföretag på den globala marknaden. Resultat: Studien har kommit fram till att de största utmaningarna för bilindustrins framtid handlar om: automatisering, miljö, ägande och digitalisering. Utöver de innovativa utmaningarna har Kina identifierats som en utmaning för bilföretagen. Eftersom Kina har en snabbt ökande medelklass i kombination med att landet har en låg biltäthet förväntas bilförsäljningen i regionen öka. Då många experter och intervjurespondenter anser att försäljningen av bilar kommer minska i västvärlden kommer därför en ökad försäljning i Kina och övriga Asien bli avgörande för många bilföretag. Volvo Cars har samma utmaningar att bemästra som de andra aktörerna på marknaden men eftersom de är en mindre aktör måste de fokusera på en eller två utmaningar och hoppas på att de är rätt. Studien har även visat att Volvo Cars satsar en stor procent av deras omsättning på just forskning och utveckling jämfört med andra (undersökta) aktörer på marknaden. Slutsats: Då Volvo Cars är en liten aktör på den globala marknaden kommer de inte ha möjlighet att satsa på samtliga utmaningar utan måste fokusera sin forskning och utveckling på ett fåtal faktorer för att kunna konkurrera på framtidens bilmarknad. Studien har specificerat tre utmaningar för Volvo Cars att uppnå för goda framtidsutsikter: lyckas växa på den kinesiska (och övriga asiatiska) marknaden och därmed öka den totala försäljningen och marknadsandelarna samt bemästra de innovativa utmaningarna inom automatisering och eldrift. Med det sagt kan forskarna dra slutsatsen att Volvo Cars framtid ser lovande ut förutsatt att de fortsätter öka sin försäljning, framförallt i Kina, samtidigt som de helhjärtat satsar på forskning och utveckling inom områdena automatisering och el-drift.
400

Driver Chassis Control Functions in New Vehicles : Based on Steering, Suspension, and Propulsion Actuators

Ryberg, Sebastian January 2017 (has links)
The thesis project is performed at ÅF Industry at their chassis department in Trollhättan, where their focus lay at chassis and body functions for the automotive industry. There are many functions in a car now a day, the act and function names for those functions have a huge variety between automotive brands. ÅF want a catalogue, with a collection of functions and what they do, how they act, pros and cons, and in- & output, with focus on steering, propulsion, and suspension actuators.    Through benchmarking, all functions have been collected in a list of functions for five different automotive brands. Another student from Karlstad University, worked parallel with a similar thesis, focusing on braking actuators. Some information passed through our theses to help each other during the benchmark. From the benchmark, five datasheets were made, to add to the catalogue. Out of those five functions one had to pass the elimination matrix to be tested and evaluated.   In this thesis, the function to be tested were Drive Profile with focus on suspension. The function was tested in a Saab 9-5 Aero equipped with an VBOX 3i at NEVS test track. Test method for the test was ISO 3888-2 severe lane-change, obstacle avoidance. The result for the test was that Sport profile was stiffer than Comfort and Intelligent, and therefore recovered the roll rate much quicker in hard cornering. The profile to choose, while entry a hard cornering is the Sport profile because of the fast roll rate recovery, also the steering torque felt way better for the driver with the Sport profile activated.     It is concluded that it is a problem with all variety of function names. Especial for customer who wants to compare cars when he/she is going to buy a new car.

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