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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.
341

Quantitative Analyse der Komplexität von Knotenpunkten und ihr Einfluss auf die Unfallhäufigkeit

Gidion, Fritjof 27 September 2019 (has links)
Innerorts-Knotenpunkten gilt aufgrund der vielen Unfälle eine hohe Aufmerksamkeit in der Unfallforschung und -prävention. Die vorliegende Arbeit identifiziert und quantifiziert Einflüsse, welche die Komplexität von Knotenpunkten bestimmen und sich so auf Fehlerraten und somit Unfallzahlen auswirken. Dazu werden verallgemeinert lineare Modelle verwendet. Dabei erweisen sich neben der Verkehrsstärke vor allem die Anzahl der Konfliktpunkte an nichtsignalisierten Knotenpunkten sowie die Links- und Rechtsabbiegersignalisierungen an signalisierten Knotenpunkten als signifikante Einflüsse auf die Unfallzahlen. Entsprechend können komplexitätsverringernde Maßnahmen abgeleitet werden. / A great deal of research on road safety and accident prevention focuses on urban intersections due to high crash frequencies. In this paper urban intersection complexity is broken down into single quantifiable effects that determine crash counts using generalised linear models. Besides traffic volumes it can be shown that the number of conflict points explain crash counts at non-signalised intersections. Whereas crash counts at signalised intersections are effected by protected left- and right-turn signalling. Practical measures can be deduced from this work in order to manage intersection safety.
342

Promoting digital authoritarianism : A study of China’s Digital Silk Road

Wahlberg Scott, Andrea January 2021 (has links)
China’s influence is increasing steadily in all corners of the world. One of China’s foreign policy goals is to become a technological superpower by 2025. An important part of that goal is the Digital Silk Road (DSR), a sub-project to China’s massive infrastructure project, the Belt and Road Initiative. The DSR is on one hand contributing to positive technological developments, especially in developing countries. But on the other hand, it has gotten substantial criticism for being a front for spreading China’s digital authoritarian model and for giving authoritarian regimes the tools to effectively repress citizens and violate human rights. The aim of this study is twofold. The first aim is to examine and map out how China might be promoting autocracy through the DSR, this will contribute to a deeper empirical understanding. The second aim is to give a theoretical contribution by categorizing autocracy promotion and testing the value of active and passive autocracy promotion in relation to China and the DSR. To conduct the analysis, I will draw on literature about autocracy promotion and digital authoritarianism. The existing literature is divided on whether or not China is promoting autocracy, and I will thus be arguing that technological advances, and the DSR, makes it problematic to claim that China is not engaged in autocracy promotion. Therefore, I seek to contribute to the existing literature. The results show that China is in fact involved in autocracy promotion through the different DSR projects. It also shows that China’s support, in some cases, have been crucial in providing authoritarian regimes with repressive technologies. The results also indicate that promoting autocracy might not be an outspoken goal or strategy from China, but rather an unintended consequence when trying to reach domestic political and economic goals.
343

Modernizace ulice Brněnská v Miroslavi / Design of Brněnská street - Miroslav

Veselý, Petr January 2022 (has links)
The subject of the diploma thesis is the elaboration of documentation for the issuance of a joint decision (DÚSP) for the project Modernization of Brněnská Street in Miroslav. The reason for the modernization is the emergency condition of the existing road and its unsatisfactory technical solution. The communication of functional group B (collection) is located in the urban area of the city. As part of the modernization of Brněnská Street, modifications of intersections, exits, sidewalks and parking spaces are also addressed.
344

Přeložka silnice II/380 Moutnice – Borkovany / Road II/380 in stage Moutnice – Borkovany - relocation study

Charvátová, Marie January 2012 (has links)
Relocation the road II/380 Moutnice – Borkovany is designed for higher traffic load centers municipalities Těšany and Moutnice, increase driving safety in the community and increase traffic flow. Part of Master´s thesis is the connection of intersecting roads 2. and 3. clases and connections to existing transport infrastructure. Relocation the road II/380 is made in three variants. Better alternative is developed in more detail. Relocation is designed in the category S7,5/70.
345

An Automatic Method to Extract Events of Drivers Overtaking Cyclists from Trajectory Data Captured by Drones

Munnamgi, H. Vasanth, Feng, Fred 03 January 2023 (has links)
Cycling as a mode of transportation has been recording an upward trend in both the U.S. and Europe. Unfortunately, the safety of cyclists has been a point of growing concern. Data from the National Highway Traffic Safety Administration (NHTSA) show that the crashes that occur during the events of motorists overtaking cyclists was one of the leading categories involving cyclists in fatal crashes. In support of the efforts to understand the driving behavior of drivers of motorized vehicles while overtaking cyclists, this research project is aimed at developing an algorithm to identify the overtaking events. Most existing quantitative studies on cycling safety leverage instrumented bicycles or vehicles with sensors for extracting naturalistic driving trajectories. Whereas we use data from a recent research that provides naturalistic driving trajectories of road users collected at select intersections in urban areas in Germany using drones equipped with cameras. Using these videos with a data frequency of 25 Hz, the authors of this study have output inD dataset. The inD dataset contains trajectories of road users that are captured in form of coordinates on a two-dimensional plane obtained from the ariel or bird's eye view of the road. Additionally, the data also captures velocity, acceleration, heading angles, dimensions of driver's vehicle etc. Overtaking can be thought of as four phases of approaching, steering away, passing, and returning. Using the inD dataset, we have developed an algorithm to identify events when a driver of motor vehicle overtakes a cyclist. This work fits into our broader goal to contribute to the body of knowledge for improving road safety of cyclists. The work is expected to provide inputs to governmental/ traffic authorities in aspects such as design of intersections and design of bicycle lanes by providing insights into overtaking events. [from Indroduction]
346

Usability of connected vehicle data for local winter road maintenance / Användbarhet av ansluten fordons data för loklat vintervägunderhåll

Lindgren, Erik January 2023 (has links)
NIRA is a company based in Linköping and operates within the automotive industry. NIRA's Tire Grip Indicator is one of their products used to create friction values during normal driving conditions. This data is, together with additional sensor information from the vehicle, such as environmental sensors, collected in NIRA's cloud environment RSI. Utilising hundred of thousand of vehicles, several products are created and offered to the market. This master thesis will focus on the winter maintenance industry business where NIRA provides refined information to support decision making and quality control for the winter maintenance operations both in Sweden and internationally. The master thesis will be conducted in close cooperation with several actors active in the winter maintenance business within the scope of a collaboration project.  The thesis explores how road surface information can be used as decision support for actors within road maintenance. The thesis starts with a literature study describing different perspectives of winter maintenance and its relation to decision support systems. Through the study, several decision support systems are used to analyse the road climate and the maintenance operations in the city of Gothenburg. The analysis takes the form of a case study where each day during the winter season is analysed. Several features are extracted from the cases and are used to classify each case as one of 6 categories. Finally, the cases are valued within three cost areas: traffic accidents, accessibility, and fuel consumption.  The findings of the thesis show that the different systems within the project fulfil different functions in the work for more efficient winter road maintenance operations, where the forecasting tools can be seen as tools for planning measures. At the same time, friction data from fleets of connected vehicles can help evaluate the outcome of maintenance actions. This applies especially to the possibility of implementing and evaluating preventive measures. The findings also show several potential benefits in using road surface forecasts and road friction data in terms of financial, socio-economic, and environmental perspectives.
347

Beläggningsskadors typ, omfattning och orsaker på statliga vägnätet / Different kind of covering damage, extent and causes on state raod network

Barzngy, Ahmad, Zangana, Majid January 2017 (has links)
Trafikverket genomför i dagsläget ett större projekt där undersökningar och analyser utav vägskador på statliga vägar utförs. Syftet med projektet är att långsiktigt förbättra möjligheterna att mäta vägnätet, försöka ta fram mätvärden som kopplar orsaken till skadornas uppkomst och varför vald underhållsåtgärd genomförs. Målet med denna studie är att med hjälp av en omfattande insamlingsfas i PMSv3, som lagrar data utifrån vägytemätningar, att kunna analysera olika typer av vägskador och dess olika egenskaper. Indata har sedan jämförts med Trafikverkets krav på underhållsstandard. Resultatet av datainsamlingen har sedan analyserats och samband mellan visuell skada och mätdata från PMSv3 har observerats. Nyttan med sambanden som har iakttagits leder till bättre förståelse om vilka huvudfaktorer som påverkar vägens nedbrytning och var dem vanligen förekommer. Totalt har 19 av 67 vägsträckor valts ut från datainsamlingen att redovisa och analysera. Det finns indikationer på sambanden utifrån resultatet som är redovisade i analysen och slutsatsen. Med hänsyn till observationerna i PMSv3 ligger denna studie för vidare fördjupning och forskning. / The transport administration currently performs a research project where they conduct investigations and analysis of road damage on state road. The purpose of the project is to in the long-term improve the possibilities to measure the road network, try to find the readings that connect the cause for the accidents and why the chosen maintenance is conducted. The aim of this study is to, with the help of an extensive collection phase in PMSv3, that stores data by road surface measurement, to be able to analyse different type of road damages and ther characteristics. Input has then been compared to the transport administrations requirement on maintenance standard. The results of the data collection has then been analysed and conection between visual damage and data from PMSv3 has been observed. The usefulness of the connections that have been observed lead to better understandnings on what main factors that affect the roads breaking down and where they frequently occur. There are indications of connections from the results that have been demostrated in the analysis and the conclusion. With consideration to the observations in PMSv3 lies this study for further depth and research.
348

Examining the Impacts of State Route 101 on Wildlife Using Road Kill Surveys and Remote Cameras

Snyder, Sara Ann 01 August 2014 (has links) (PDF)
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).
349

Planering av förbifarter och ringleder i tätorter : En dokumentstudie om vägplanering / Planning of bypasses and ring roads in localities : A study about road planning

Kauppi, Jonathan January 2024 (has links)
We are constantly building new roads and are trying to make them safer and more efficient. This thesis has looked into how the benefits and disadvantages has been described with building new roads and specifically bypass roads. The thesis has also explored on how the handling of the citizens have been made from the municipal part and from the side of the Swedish Transport Administration. The analysis in this study has been made with a directed content analysis, this means that the previous scientific research and theories have been used to form the framework used in the coding scheme. Documents from the municipalities and planning documents from the Swedish Transport Administration have been used in the coding scheme. In total 10 documents combined have been analyzed from Skellefteå, Söderköping and Linghem connected to the building of bypass roads in the localities.  The study has shown that in all the localities there are negative effects on the environment, landscape and land that is being used, but in all the cases the Swedish Transport Administration and the municipalities argue that the roads have more positive benefits than negative, the bypass roads lead to a higher traffic safety, less emissions and a better accessibility in the central parts of the localities. Regarding the communications it’s clear that the municipalities prioritize the inhabitants and are constantly working to improve it. The Swedish Transport Administration works with communication in all the stages in the planning process. Both the municipalities and the Swedish Transport Administration describe that they value the public interest higher than the private. But with how the Swedish Transport Administration works with communicative planning it could be concluded that they only follow the necessary steps that they are legally required to.
350

Automatic reconstruction of realistic road networks from GIS data / Reconstruction de réseaux routiers réalistes à partir de données SIG

Nguyễn, Hoàng Hà 18 March 2016 (has links)
La reconstruction de routes est un sujet important dans le domaine de la modélisation 3D. Nous proposons dans cette thèse des méthodes pour construire des modèles de réseaux routiers réalistes à partir de données SIG.Tout d'abord, les problèmes de la reconstruction d'un simple axe de route à partir d'une polyligne sont étudiés. Nous présentons un modèle de courbe par morceaux G1 qui est non seulement fidèle à l'axe de la route réelle mais aussi pratique et pas onéreux à obtenir. Notre algorithme Least Square Growing crée, comme dans le génie civil, une courbe horizontale et une courbe verticale, puis les combine pour produire un axe routier 3D approchant la polyligne. Traiter individuellement des polylignes conduit à des discontinuités aux intersections des routes. C’est pourquoi nous introduisons une procédure pour détecter les relations entre les routes, afin de proposer un processus global pour reconstruire tous les axes routiers avec prenant en compte les nouvelles contraintes sur les extrémités des routes.Enfin, sur la base de l'axe de la route et les propriétés résultant de la route dans la base de données SIG, nous définissons un modèle mathématique de la surface de la route en respectant les contraintes essentielles de surfaces routières réelles. Pour produire une géométrie représentant la surface de la route finale, nous construisons un maillage grossier de la carte d'élévation du terrain d'entrée, que nous subdivisons adaptativement le long de l'axe de la route, puis ajustons l'altitude des sommets concernés à la valeur définie par le modèle mathématique de la route afin de parvenir à une correspondance correcte entre le terrain et la vraie route. / Road reconstruction is an important topic in 3D modeling. Recently, the steady development of many critical-accurate applications has posed a high demand for realistic road models, taking into account road-design constraints selected from civil engineering. We propose in this dissertation methods for building realistic road network models from GIS data.Firstly, problems of single road axis reconstruction from a polyline are addressed. We present a novel G1-piecewise-curve model which is not only faithful to the real road axis but also convenient and cheap to render. Our Least Square Growing Algorithm creates, as in civil engineering, an horizontal and a vertical curves, then combines them to produce a 3D road axis fitting well the polyline. Processing individual polyline will leads to the discontinuities at road intersections so we introduce a procedure to detect road relations, then we propose a global process to reconstruct all road axes with the considerations on further constraints of road ends.Finally, based upon the resulting road axis and road properties in the GIS database, we define a mathematical road surface model respecting the essential constraints of real road surfaces. To produce a geometry representing the final road surface, we build a coarse mesh from the input terrain highmap, subdivide it adaptively along the road axis, then adjust the altitude of concerning vertices to the value defined by the mathematical model in order to attain a correct mapping between the terrain and the real road.

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