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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.
81

Analyzing the Safety Effects of Edge Lane Roads for All Road Users

Lamera, Marcial F 01 September 2020 (has links) (PDF)
This thesis acts as one of the first studies that analyzes the safety effects of Edge Lane Roads (ELR) for all road users. This is important since ELRs can be a solution to many issues, such as alleviating congestion, increasing multimodality along roadways, and reducing maintenance costs. ELRs in both North America and Australia were observed. Starting with the North American ELRs, the following study designs were employed to estimate the safety of ELRs: (a) yoked comparison where each ELR installation was matched with at least two comparable 2-lane roads to serve as comparison sites and (b) an Empirical Bayes (EB) before/after analysis for ELR sites where requisite data on AADT and other relevant characteristics were available. Crash data was collected and compiled into four different groups: ELR before implementation, ELR after implementation, comparison site before ELR implementation, and comparison site after ELR comparison. The yoked comparison showed 9 of the 13 sites that had lower crash counts compared to their respective comparison sites. The EB analysis showed all 11 ELRs that were observed demonstrated a reduction in crashes. Moving to the Australian ELRs, the following study designs were employed: (c) analysis of general crash counts/trends, and (d) reverse EB analysis. The analysis of general crash counts and trends showed that each of the Australian ELRs exhibited very low amounts of crashes for 5 years, which further shows how safe these facilities are. Moving forward to the reverse EB analysis, 5 of the 8 ELR sites demonstrated a reduction in crashes. Overall, the results were generally favorable and indicated that ELRs provided a safer experience for cyclists, drivers, and pedestrians. More analysis is recommended as more data becomes available on these ELRs. Examples of this include using pedestrian and bicycle data to better understand the safety effects VRUs experience on North American facilities or gathering enough crash data to conduct 3-year reverse EB analyses for ELRs that were expanded to 2-lane roads. Hence, a recommendation can be made to implement a few experimental ELRs in rural locations throughout the State of California to help it meet its SB-1 objectives.
82

Brobanor och dess egenskaper för kommande höghastighetsjärnväg : Brobanors användning och egenskaper i samband med höghastighetsjärnväg / Bridge tracks and their characteristics for upcoming high-speed railway : Use and characteristics of bridge lanes in the context of high-speed rail

Zubanovic, Haris, Saakyan, Hajk January 2023 (has links)
SammanfattningSvensk järnväg har aldrig varit mer belastad och trafikerad än idag, och värre kommer det att bli. Det har inte pågått några större investeringar i svensk järnväg sen 1990-talet, effekterna av den strategin börjar bli alltmer uppenbar. Sveriges järnvägssystem i jämförelse med många europeiska länder och även utanför Europa är teknologiskt och innovativt undermålig. Höghastighetståg som överstiger 250 km/h är ännu bara ett koncept i Sverige medan i länder som Frankrike, Tyskland, Kina och Japan är detta sen flera år tillbaka en verklighet. Det finns framträdande fördelar med etableringen av höghastighetsjärnväg som överstiger hastigheter på 250km/h. Utbyggnaden av höghastighetsjärnväg medför ett avsteg från konventionella järnvägsmetoder så som banvallar, i stället används prefabricerade broelement som möjliggör fast gjutning av spåret och utan användningen av ballast. Denna metod banar väg för högre tåghastigheter, mindre underhållsåtgärder, längre livslängd, passager under bron av befintlig transportinfrastruktur och besparing av natur och djurliv. Ovannämnda länder har kunnat omdirigera trafikbelastning på övriga transportsystem så som vägar och inrikes flygresor. En mindre belastning på exempelvis vägnätverket, leder till bättre trafikförhållanden, mindre slitage på vägbana och därmed sänkta kostnader för underhåll. Ur ett miljö- och hållbarhetsperspektiv minskar även utsläppet av farliga gaser och partiklar så som koldioxid, samt dämpar konsumtionen av fossila bränslen till fossildrivna fordon. Syftet med examensarbetet är att lyfta fördelarna med utbyggnaden av höghastighetsjärnväg i Sverige. Där fokus ligger i att göra detta genom att frångå den konventionella metoden av banvallar och i stället implementera brobanor med dess många framträdande fördelar. Arbetet genomsyras av utländska perspektiv gällande utbyggnad och underhåll, där höghastighetsjärnväg förlagd på bro används i större omfattning. Detta medför att arbetet kan erbjuda relevanta perspektiv från länder som exempelvis Kina som är världsledande inom området. Förhoppningen är att arbetet ska kunna användas som underlag för framtida järnvägsprojekt i Sverige. Resultatet för rapporten innehåller tre delar, kostnad, underhållsåtgärder samt miljö- och hållbarhetsperspektiv. Arbetet har redogjort för en grov kostnadsindikation på vad det kan kosta att bygga 1 km broförlagt ballastfritt dubbelspår, slutkostnaden hamnade på 929 miljoner kr med en standardavvikelse på ± 30 %. Underhåll av höghastighetsjärnväg på brobanor påvisas av många länder vara minimal. Det som möjliggör detta är innovativ detekteringsteknologi som regelbundet återger skick och funktionsduglighet av såväl banan som bron. Brobanor konstrueras för långa livslängder, det slitage som uppstår är generellt kopplat till rälsslipning och så kallade kritiska punkter vid sammanfogning av prefabricerade broelementen där det finns större risk för sprickbildning med mera. / Swedish railways have never been more congested than today, and it will get worse. There has been no major investment in Swedish railways since the 1990s, and the effects of that strategy are becoming increasingly apparent. Sweden's railway system, compared to many European countries and even countries outside Europe, is technologically and innovatively inferior. High-speed trains exceeding 250 km/h are still only a concept in Sweden, whereas in countries such as France, Germany, China, and Japan this has been a reality for several years. There are prominent advantages to the establishment of high-speed rail exceeding speeds of 250km/h. The development of high-speed rail involves a departure from conventional railway methods such as embankments, instead using prefabricated bridge elements that allow for the fixed casting of the track and without the use of ballast. This method paves the way for higher train speeds, less maintenance, longer service life, passage under the bridge of existing transport infrastructure, and conservation of nature and wildlife. The above-mentioned countries have been able to redirect traffic loads from other transport systems such as roads and domestic air travel. Less strain on the road network, leads to better traffic conditions, less wear and tear on the road surface and thus reduced maintenance costs. From an environmental and sustainability perspective, it also reduces emissions of hazardous gases and particulates such as carbon dioxide and curbs the consumption of fossil fuels by fossil fuel powered vehicles.The aim of the thesis is to highlight the benefits of the expansion of high-speed rail in Sweden. The focus is to do this by abandoning the conventional approach of embankments and instead implementing bridge lanes with its many prominent advantages. The work is permeated by foreign perspectives regarding development and maintenance, where high-speed rail on bridges is more widely used. This means that the work can offer relevant perspectives from countries such as China, which is world leading in this field. It is hoped that the work can be used as a basis for future railway projects in Sweden. The result of the report contains three parts, cost, maintenance measures and environmental and sustainability perspectives. The work has given a rough cost indication of what it might cost to build 1 km of bridge-laid ballastless double track, the final cost ended up at 929 million SEK with a standard deviation of ± 30%. Maintenance of high-speed rail on bridge tracks is shown by many countries to be minimal. This is made possible by innovative detection technology that regularly reproduces the condition and operability of both the track and the bridge. Bridge decks are designed for long lifetimes, the wear and tear that occurs is generally related to rail grinding and so-called critical points in the joining of prefabricated bridge elements where there is a higher risk of cracking etc.
83

De la ville de l'automobile à la ville des transports collectifs : le cas des sites propres bus du sud est parisien / Interaction between speed and urban morphology : from the auto city to transit city

El Hadeuf, Mounya 14 June 2017 (has links)
Cette thèse explore la relation entre urbanisme et transport par l’étude de projets de bus en site propre dans dix villes de la proche banlieue parisienne, territoire qui dispose à la fois d’une accessibilité correcte à la ville-centre et d’opportunités foncières susceptibles de constituer un réel potentiel de « reconstruction de la ville sur la ville ». À travers l’étude de documents d’archives, elle retrace la genèse, entre propositions, négociations, adaptations et déploiements de ces projets de transport, et la complète par l’analyse de l’évolution des territoires urbains traversés, sur une période de 30 ans, grâce notamment à l’exploitation de la base de données des Modes d’Occupation des Sols de l’IAU-IDF. En s’appuyant sur cette double démarche, cette thèse tente d’appréhender le concept d’« urbanisme orienté par les transports collectifs » et met en évidence des stratégies contrastées des communes traversées face à l’arrivée de ce type de projet de transport, ainsi que les corrélations qui peuvent exister entre ces stratégies, l’histoire de ces communes et leur composition socio-démographique. Elle révèle également des écarts entre les volontés affichées et les réalisations conduites ou les résultats obtenus, écarts dont les causes peuvent être diverses, mais qui permettent de mieux comprendre les efforts qui restent à conduire dans différents domaines pour mieux assurer la cohérence entre projets transport et projets urbains. Les exemples traités montrent que le projet de bus en site propre peut constituer le socle d’une action en faveur d’un « urbanisme orienté par les transports collectifs » ou n’engendrer qu’un « transport orienté par le développement urbain ». Dans les deux cas, on peut considérer sa réalisation comme une réussite selon les critères de performance du système de transport, ou estimer que dans le second cas, une partie seulement des potentialités du projet ont été réalisées, et qu’il est possible d’en tirer des enseignements pour faire évoluer les pratiques et les dispositifs existants / This thesis explores the relationship between urban planning and transport, by studying dedicated bus lanes projects in ten cities of the near Parisian suburb, a territory which has both correct accessibility to the city-centre and real estate opportunities, so that it can constitute a potential of « rebuilding the city over the city ». By studying archival documents, it traces the genesis of these dedicated bus lanes, from propositions, to negotiations, adaptations and deployments, associated with the analysis of the urban evolution of the concerned territories, during 30 years, mainly by using the land-use database from IAU-IDF. By this double approach, the research tries to understand the concept of « Transit Oriented Development » and assesses contrasted strategies of concerned cities toward these types of projects, and highlights the correlation between these strategies and city’s history and the social demographic composition. It also reveals the gap between the stated will and undertaken implementation or achieved results, a difference that may have various causes, but also enables to understand the different efforts that must be made to ensure the coherence between transport projects and urban projects. A dedicated bus lane can be a basis for an action in favour of a « Transit Oriented Development » or lead to a « development oriented transit ». In both cases, we can consider its implementation as a success, according to transport systems criteria, or deem that in the second case, only a part of the project potentialities were achieved, and that it is possible to learn from these experiences to develop the current practices and process
84

Pedestrian safety at signalized intersections operating the flashing yellow arrow

Tuss, Halston 21 September 2012 (has links)
At signalized intersections, pedestrians are considered to be amongst the most vulnerable. When in the crosswalk at intersections without protected left-turn phasing, pedestrians are particularly at risk from left-turning vehicles. Until recently, a wide variety of indications were in use across the US to indicate a permissive left-turn condition to the driver. In Oregon, the Flashing Yellow Arrow (FYA) has been used to indicate the permissive left-turn condition for approximately 10 years. With the addition of the FYA in the 2009 MUTCD, it is likely that its use will continue to increase nationally. Though many operational and safety issues have been studied about the FYA indication, this research proposes to fully investigate factors that influence driver behavior in the context of the permissive left-turn conflict with pedestrians. Specifically, the research seeks to study driver glance behavior to identify reasons why drivers are, "looking at but not seeing" pedestrians in or near the crosswalk or not searching for the presence of pedestrians at all. / Graduation date: 2013
85

Wirksamkeit von Maßnahmen zur Verbesserung der Verkehrssicherheit auf einbahnigen Landstraßen

Jährig, Thomas 31 July 2012 (has links) (PDF)
An einbahnige Außerortsstraßen (Landstraßen) werden sehr hohe Anforderungen gestellt. Einerseits sollen sie eine hohe Verkehrssicherheit aufweisen und andererseits gemäß ihrer Verkehrsbedeutung eine angemessene Verkehrsqualität und Leistungsfähigkeit bereitstellen. Im Landstraßennetz liegt die Erfüllung dieser Anforderungen jedoch vielerorts deutlich unter den Erwartungen. Unfälle auf Landstraßen sind im Vergleich zu Autobahnen oder Innerortsstraßen durch eine besonders hohe Schwere gekennzeichnet. Sehr hohe und oft an den Streckenverlauf nicht hinreichend angepasste Geschwindigkeiten, Fehleinschätzungen von Geschwindigkeiten bzw. Geschwindigkeitsdifferenzen entgegenkommender und vorausfahrender Fahrzeuge sowie die im Standardfall für Überholvorgänge notwendige Nutzung des Gegenfahrstreifens sind die Hauptursachen für die schweren Unfälle auf Landstraßen. Das Ziel der vorliegenden Arbeit war die Untersuchung der Wirksamkeit von kurz- und mittelfristig umsetzbaren Maßnahmen zur Verbesserung der Verkehrssicherheit auf unfallauffälligen einbahnigen Außerortsstraßen. Die Untersuchungen dafür erfolgten im Rahmen des Großversuches „Außerortsstraßensicherheit“ (AOSI). Im Ergebnis sollten Einsatzempfehlungen für die Planungs- und Entwurfspraxis und für zukünftige Regelwerke für den Landstraßenentwurf abgeleitet werden. Für die Durchsetzung der zulässigen Höchstgeschwindigkeit wurden auf fünf ausgewählten Bundesstraßenabschnitten linienhaft angeordnete ortsfeste Geschwindigkeitsüberwachungsanlagen (OGÜ) eingerichtet. Auf fünf weiteren Bundesstraßenabschnitten wurde das Überholen nur auf den dafür angelegten Überholfahrstreifen (ÜFS) zugelassen. Auf den verbliebenen zweistreifigen Zwischenabschnitten wurden Überholverbote (ÜV) erlassen. Nach dem von der AOSI-Projektgruppe vorgegebenen Messregime und den so ermittelten Rohdaten wurde eine eigene Untersuchungsmethodik entwickelt und die vorliegende Datenlage entsprechend aufbereitet. Darauf gestützt erfolgte die Auswertung und Interpretation sowie die Ableitung der Empfehlungen. Durch die linienhafte ortsfeste Geschwindigkeitsüberwachung konnte eine deutliche Verbesserung der Verkehrssicherheit erzielt werden und damit das Unfallrisiko auf den Untersuchungsstrecken teils erheblich reduziert werden. Es konnte gezeigt werden, dass die Grundlage dieser Entwicklung die Durchsetzung der zulässigen Höchstgeschwindigkeit war, die vor der Überwachung um bis zu 20 km/h überschritten wurde. Diese Entwicklung war nicht nur auf eine Reduktion der Fahrunfälle zurückzuführen. Durch die Verringerung der Geschwindigkeitsunterschiede zwischen den Fahrzeugen sank der Überholdruck, was besonders auf den Untersuchungsstrecken mit einer gestreckten Linienführung auch einen Rückgang der Unfälle im Längsverkehr bewirkte. Nach der Eingewöhnungszeit stellte sich das erwartete Fahrverhalten entlang der Untersuchungsstrecken ein, das nicht mehr durch deutliche Verzögerungs- und Beschleunigungsvorgänge im Bereich der Geschwindigkeitsüberwachungsanlagen geprägt war. Förderlich für diese Entwicklung war trotz anfänglicher Skepsis die breite Akzeptanz der Kraftfahrer zu den OGÜ-Anlagen als sinnvolle Maßnahme zur Verbesserung der Verkehrssicherheit. Erreicht wurde dies mit einer verständlichen Öffentlichkeitsarbeit zu den Hintergründen und Zielen der Maßnahme. Die Kombination von abschnittsweisen sicheren Überholmöglichkeiten (ÜFS) und Überholverboten in den einbahnig zweistreifigen Zwischenabschnitten (ÜV) ist eine geeignete, mittelfristig umsetzbare Maßnahme zur Verbesserung der Verkehrssicherheit. Die Wirkung der Maßnahme ist vorrangig auf die Unfälle im Längsverkehr gerichtet und sollte daher auf Strecken erwogen werden, bei denen das Unfallgeschehen vor allem durch einen hohen Anteil von Überholunfällen gekennzeichnet ist. Der Vorteil liegt im Abbau des Überholdrucks unabhängig von den verfügbaren Zeitlücken im Gegenverkehr. Dafür haben sich auch kurze Überholfahrstreifen (l ≥ 600 m) bewährt, die im Bestandsnetz eher realisierbar sind. Die untersuchte Maßnahmenkombination aus einem sicheren Überholangebot und einem Überholverbot in den einbahnig zweistreifigen Abschnitten erfährt zudem eine hohe Akzeptanz bei den Verkehrsteilnehmern. Durch die Ergebnisse dieser Arbeit liegen Empfehlungen vor, um die Verkehrssicherheit auf unfallauffälligen Abschnitten einbahniger Außerortsstraßen kurz- und mittelfristig zu verbessern. Dies gilt vor allem dann, wenn das Unfallgeschehen vorrangig auf eine zu hohe und unangepasste Geschwindigkeit oder auf Fehler bei Überholvorgängen zurückzuführen ist. Die Ergebnisse liefern darüber hinaus belastbare Grundlagen für das neue Regelwerk für den Landstraßenentwurf.
86

Multi-viewpoint lane detection with applications in driver safety systems

Borkar, Amol 19 December 2011 (has links)
The objective of this dissertation is to develop a Multi-Camera Lane Departure Warning (MCLDW) system and a framework to evaluate it. A Lane Departure Warning (LDW) system is a safety feature that is included in a few luxury automobiles. Using a single camera, it performs the task of informing the driver if a lane change is imminent. The core component of an LDW system is a lane detector, whose objective is to find lane markers on the road. Therefore, we start this dissertation by explaining the requirements of an ideal lane detector, and then present several algorithmic implementations that meet these requirements. After selecting the best implementation, we present the MCLDW methodology. Using a multi-camera setup, MCLDW system combines the detected lane marker information from each camera's view to estimate the immediate distance between the vehicle and the lane marker, and signals a warning if this distance is under a certain threshold. Next, we introduce a procedure to create ground truth and a database of videos which serve as the framework for evaluation. Ground truth is created using an efficient procedure called Time-Slicing that allows the user to quickly annotate the true locations of the lane markers in each frame of the videos. Subsequently, we describe the details of a database of driving videos that has been put together to help establish a benchmark for evaluating existing lane detectors and LDW systems. Finally, we conclude the dissertation by citing the contributions of the research and discussing the avenues for future work.
87

Návrh cestní sítě v komplexní pozemkové úpravě / Proposal of road network for complex land adjustment

FLORIÁN, Ondřej January 2015 (has links)
The main purpose of this thesis was compiling the detailed literature search containing the description of a road network from the historical development point of view, detail characteristics of lane types used in complex land adjustment and the evaluation of the road and lane network as a possible element of erosion control. The main object was the analysis of the road and lane network changes during several historical periods, in which the network was captured, studied and the results were compared. The possible causes of the changes where described for key moments of the historical development. As the location of interest the cadastral area Nakri in Ceske Budejovice district was chosen. For this location the detailed road and lane network analasys shows clear overview of remarkable changes during historical development. A part of this thesis is not only capturing the changes, but also a proposal of resolved complex land adjustment, which is in compliance with latest requirements for proposing a plan of common facilities.
88

Impacts of User Heterogeneity and Attitudinal Factors on Roadway Pricing Analysis - Investigation of Value of Time and Value of Reliability for Managed Lane Facilities in South Florida

Hossan, Md Sakoat 23 February 2016 (has links)
Managed lane refers to the application of various operational and design strategies on highway facilities to improve system efficiency and mobility by proactively allocating traffic capacity to different lanes. One of the key elements to understand the behavior changes and underlying causalities in user responses to managed lanes is to examine the value of time (VOT) and value of reliability (VOR). The breadth of this dissertation encompasses two major dimensions of VOT and VOR estimation – distributions or variations across different users and under different circumstances; and influences of unobserved attitudinal characteristics on roadway pricing valuation. To understand travelers’ choice behavior regarding the usage of managed lanes, combined revealed preference (RP) and stated preference (SP) data were used in this study. Mixed logit modeling was applied as the state of the art methodology to capture heterogeneity in users’ choice behavior. The model revealed an average value of $10.68 per hour for VOT and $13.91 per hour for VOR, which are reasonable considering the average household income in the region, and are well within the ranges found in the literature. In terms of user heterogeneity, the mixed logit model was further enhanced by adding interaction effects of variables, which helped recognize and quantify potential sources of heterogeneity in user sensitivities to time, reliability, and cost. The findings indicated that travelers were likely to exhibit higher willingness to pay when they were female, younger (years), older (>54 years), had higher income (> 50 K), driving alone, and traveled on weekdays. Attitudinal aspects are rarely incorporated into roadway pricing analysis. The study herein presents an effort to explore the role of attitudinal factors in drivers’ propensity toward using managed lanes. Model results boded for a significant contribution of attitudinal parameters in the model, both in terms of coefficients and model performance. This study provides a robust approach to quantify user heterogeneity in VOT and VOR and capture the impacts of attitudinal attributes in pricing valuation. The results of this study contribute to a better understanding on what attributes lead to higher or lower VOT and VOR and to what extent.
89

Optimalizace návrhových prvků pozemních komunikací pomocí vlečných křivek vozidel / Optimizing of road design elements by means of vehicles’ swept paths

Čepil, Jiří Unknown Date (has links)
The dissertation deals with application of simulated swept paths of vehicles to road designs. Using software which generates simulated swept paths makes new demands on the designer, but Czech regulations do not stipulate the appropriate method of applying swept paths. The theoretical part of the dissertation analyses the theory of how a vehicle moves when passing through a horizontal road curve and a method of calculating a necessary extent of widening the road. The practical part compares swept paths generated by various software programs and differences between them. In order to verify the shapes and dimensions of the swept paths generated, the swept path of a real vehicle was measured. This swept path was then compared with the one generated, and the differences between them were evaluated. One of the software programs was chosen as a reference program, and its output was applied to a road design pursuant to valid regulations. The results obtained within the dissertation were used to develop certified methodology titled: „Methodology of widening road lanes in horizontal curves and of application of vehicles’ swept paths “.
90

Novostavba polyfunkční budovy, Jihlava / Newly-built mixed-use building, Jihlava

Kratochvíl, Aleš January 2016 (has links)
The subject of this thesis is the construction and maintenance of project documentation for the implementation of the multipurpose building in Jihlava. Designed building is located in the southern town of Jihlava, in the slightly hilly terrain on the west side. The house is rectangular ground plan, with a projecting portion bowling lanes. Roofing form a single-slope roof. It is a multifunctional building, the first floor consists of a restaurant with bowling lanes in the second and third floor houses the Tax Office. They used conventional and traditional building materials. The thesis also specializing on the subject of air conditioning and heating.

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