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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.
11

Assessment of Midblock Pedestrian Crossing Facilities using Surrogate Safety Measures and Vehicle Delay

Anwari, Nafis 01 January 2023 (has links) (PDF)
This dissertation has contributed to the pedestrian safety literature by assessing and comparing safety benefits and traffic efficiency among midblock Rectangular Rapid Flashing Beacon (RRFB) and Pedestrian Hybrid Beacon (PHB) sites. Video trajectory data were used to calculate pedestrian Surrogate Safety Measures (SSMs) and vehicles' delay. Regression models of SSMs and vehicles' delay revealed that PHB sites offer more safety benefits, at the expense of increased vehicles' delay, compared to RRFB sites. The presence of the PHB, weekday, signal activation, lane count, pedestrian speed, vehicle speed, land use mix, traffic flow, time of day, and pedestrian starting position from the sidewalk have been found to be significant determinants of the SSMs and vehicles' delay. Another avenue of pedestrian safety explored in this dissertation is the lag time. The study investigates survival likelihood and the lag time of non-instant pedestrian fatalities using random parameter Binary Logit and Ordered Logit models. The models were run on a dataset obtained from the Fatality Accident Reporting System (FARS) for the period of 2015-2019. The analysis revealed that weather, driver age groups, drunk/ distracted/ drowsy drivers, hit and run, involvement of large truck, VRU age group, gender, presence of sidewalk, presence of intersection, light condition, and speeding were common significant factors for both models. The factor found to be significant exclusively for the Binary Logit model includes Area type. Factors found to be significant exclusively for the Ordered Logit model include Presence of Crosswalk and Fire station nearby. The results validate the use of lag time as an alternative to crash count and crash severity analysis. The findings of this study pave the way for practitioners and policymakers to evaluate the effectiveness of midblock pedestrian crossing facilities, as well as to use lag time to investigate crashes and corroborate results from traditional crash-based investigations.
12

Modeling Spatiotemporal Pedestrian-Environment Interactions for Predicting Pedestrian Crossing Intention from the Ego-View

Chen Chen (11014800) 06 August 2021 (has links)
<div> <div> <div> <p>For pedestrians and autonomous vehicles (AVs) to co-exist harmoniously and safely in the real-world, AVs will need to not only react to pedestrian actions, but also anticipate their intentions. In this thesis, we propose to use rich visual and pedestrian-environment interaction features to improve pedestrian crossing intention prediction from the ego-view. We do so by combining visual feature extraction, graph modeling of scene objects and their relationships, and feature encoding as comprehensive inputs for an LSTM encoder-decoder network. </p> <p>Pedestrians react and make decisions based on their surrounding environment, and the behaviors of other road users around them. The human-human social relationship has already been explored for pedestrian trajectory prediction from the bird’s eye view in stationary cameras. However, context and pedestrian-environment relationships are often missing in current research into pedestrian trajectory, and intention prediction from the ego-view. To map the pedestrian’s relationship to its surrounding objects we use a star graph with the pedestrian in the center connected to all other road objects/agents in the scene. The pedestrian and road objects/agents are represented in the graph through visual features extracted using state of the art deep learning algorithms. We use graph convolutional networks, and graph autoencoders to encode the star graphs in a lower dimension. Using the graph en- codings, pedestrian bounding boxes, and human pose estimation, we propose a novel model that predicts pedestrian crossing intention using not only the pedestrian’s action behaviors (bounding box and pose estimation), but also their relationship to their environment. </p> <p>Through tuning hyperparameters, and experimenting with different graph convolutions for our graph autoencoder, we are able to improve on the state of the art results. Our context- driven method is able to outperform current state of the art results on benchmark dataset Pedestrian Intention Estimation (PIE). The state of the art is able to predict pedestrian crossing intention with a balanced accuracy (to account for dataset imbalance) score of 0.61, while our best performing model has a balanced accuracy score of 0.79. Our model especially outperforms in no crossing intention scenarios with an F1 score of 0.56 compared to the state of the art’s score of 0.36. Additionally, we also experiment with training the state of the art model and our model to predict pedestrian crossing action, and intention jointly. While jointly predicting crossing action does not help improve crossing intention prediction, it is an important distinction to make between predicting crossing action versus intention.</p> </div> </div> </div>
13

Analýza příčin dopravních nehod vozidel s chodci na vybraných přechodech pro chodce / Analysis of the Causes of Traffic Accidents Involving Vehicles and Pedestrians on Selected Pedestrian Crossings

Šimáková, Aneta January 2017 (has links)
A master’s thesis deals with a problem of traffic accidents on pedestrian crossings. A theoretical part describes causes and following responsibilities of all participants of the traffic accident. Furthermore, the theoretical part analyzes a traffic system and its individual parts. A practical part of this thesis describes all measuring tools used for collection of data during the analysis. The data was obtained during a real traffic on chosen pedestrian crossing in Brno A tool used for analysis is called eyetracer. Furthermore, an evaluation of collected data and following analysis were carried out. Eventually, results were compared with reports about accidents which happened on chosen pedestrian crossings.
14

Rekonstrukce křižovatky ulic Jeremenkova a Pasteurova v Olomouci / Reconstruction of intersection of streets Jeremenkova and Pasteurova in the city of Olomouc

Reiter, Tomáš January 2018 (has links)
This diploma thesis deals with the reconstruction of intersection streets Jeremenkova, Pasteurova and Černá cesta. This design is a new roundabout with three branches and one bypass. The aim of renovation is to improve traffic safety at the intersection and increasing continuity and respecting architectural principles. This project addresses the design of roundabout, analyzing problems and developer technical studies.
15

Människors beteende vid övergångsställen 14 år efter Zebralagens införande : En studie om förares och fotgängares agerande vid obevakade övergångsställen i Tyresö kommun / The behaviour of people at pedestrian crossings 14 years after the Zebra law was established : A study about drivers and pedestrians acting around unsupervised pedestrian crossings in Tyresö kommun

Elmström Eurén, Kristina, Stjernström, Johanna January 2014 (has links)
Många gående skadas eller dör i trafiken varje år. En stor del av olyckorna inträffarvid övergångsställen, flest olyckor sker vid obevakade övergångsställen. Nollvisionenär ett långsiktigt mål att ingen människa ska behöva skadas eller dö itrafiken. Somett ytterligare steg mot  nollvisionen infördes år 2000 den så kallade”Zebralagen”, en lag som innebär att fordonsförare har väjningsplikt gentemotgående. Eftersom denna lag är aktuell i samhällsdebatten har vi valt attstudera hur lagen efterlevs i praktiken detta genom att observera fyra olikatyper av övergångsställen vid sammanlagt 14 olika tillfällen och olika tider pådygnet (vardagar mellan 6-20). För att kunna jämföra observationerna medförares och fotgängares påstådda agerande har även 100 stycken enkäter delatsut och sammanställts. Utifrån dessa studier och sammanställningar har vi kommitfram till resultatet att människor upplever sig själva vara betydligt meruppmärksam och skötsamma i trafiken än vad de egentligen är och även attutformningen på övergångsstället har stor påverkan på fordonsförarna men ingenalls på fotgängarna. / Many people walking in traffic gets injured or killed in traffic each year. The place where this occurs mostly is on zebra crossings, the ones that have no surveillance are the ones where the accidents are most common. A vision zero has been establish to create a long term goal to make sure that no persons gets injured or killed in traffic. To enhance vision zero has a “zebra law” been instate year 2000, the law states that cars needs to give way for people walking. This law has been discussed in media and that is why we want to do this research about it. We did the research through observation at four different zebra crossings during 14 different times and different times of the day, all between 6 am and 8 pm. To get the people who is walking and the drivers opinions about their experiences in traffic was a survey answered by 100 participants and then analysed conducted and analysed with 100 participants. The results shows that people believe that they are more observant in traffic then what the observations has shown is true. The design of the zebra crossings did also play a role in how observant the drivers were but did not have the same effect on the people walking.
16

PreCro : A Pedestrian Crossing Robot / PeCro - roboten som hjälper människor med synnedsättning i trafiken

HEDBERG, EBBA, SUNDIN, LINNEA January 2020 (has links)
For people who suffer from visual impairment, getting around in traffic can be a great struggle. The robot PeCro, short for Pedestrian Crossing, was created as an aid for these people to use at pedestrian crossings equipped with traffic lights. The prototype was constructed in Solid Edge ST9 as a three wheeled mobile robot and consists of several components. The microcontroller, Arduino Uno, was programmed in Arduino IDE. The vision sensor used was a Pixy2 camera that can detect and track selected colour codes. A steering model called differential drive is used. It is controlled through magnetic encoders mounted on the two motor shafts. PeCro scans the environment looking for green light. If detected, PeCro searches for the blue box on the traffic light pillar on the opposite side of the street. When it is detected it crosses the street and turns 180 degrees to enable crossing the street again. The performance of a vision sensor in different light environments, the efficiency of magnetic encoders measuring travelled distance and regulating steering as well as linear interpolation as a distance calculation method, was studied. The results show that the detecting performance of PeCro is affected by the light environment and the maximum distance at which the used colour codes are detected, was 163 cm respective 150 cm. Another result shows that when measuring distance with magnetic encoders, a constant distance deviation from the desired distance occurs. This method is desirable compared to using linear interpolation to measure the distance. In conclusion, to implement and use PeCro in real life situations, further development has to be done. / Människor som lever med synnedsättning kan möta stora hinder när de rör sig i stadstrafik. Roboten PeCro, förkortning av Pedestrian Crossing (övergångsställe), skapades för att användas som ett hjälpmedel för dessa personer vid övergångsställen utrustade med trafikljus. Prototypen konstruerades som en mobil robot försedd med tre hjul i CAD-programmet Solid Edge ST9 och består av ett flertal komponenter. Mikrokontrollern, Arduino Uno, programmerades i Arduino IDE. En Pixy2-kamera användes som bildsensor som kan spåra och detektera färgkoder. Differentialstyrning användes för att enkelt kunna styra PeCro med hjälp av magnetiska givare som var fästa på motoraxlarna. PeCro skannar sin omgivning. Om den ser grönt ljus, börjar den leta efter den blå lådan på gatustolpen på motsatt sida vägen. När den blåa lådan detekteras åker roboten över övergångsstället och roterar 180 grader för att kunna användas i motsatt riktning, tillbaka över vägen. I projektet studerades en bildsensors prestanda i olika ljusmiljöer, de magnetiska givarnas effektivitet vid avståndsmätning och dess reglering av styrningen, samt avståndsmätning genom linjär interpolation. Från resultaten kan ses att PeCros detektering påverkas av ljusmiljön och att det maximala avståndet som respektive färgkod kan detekteras på är 163 respektive 150 cm. Vidare kan ses att vid avståndsmätning med magnetiska givare uppstår en konstant avvikelse från den önskade sträckan. Avståndsmätning med magnetiska givare är att föredra framför mätning med linjär interpolation. Avslutningsvis, om PeCro ska kunna användas i vardagliga situationer, kommer viss vidareutveckling behöva genomföras.
17

Nivo usluge na nesignalisanim pešačkim prelazima / Level of service at unsignalized pedestrian crossings

Mitrović Simić Jelena 14 March 2016 (has links)
<p>Istraživanje koje je sprovedeno u okviru disertacije poslužilo je za definisanje matematičkog modela koji se može primeniti u postupku određivanja nivoa usluge za nesignalisane pešačke prelaze. Formirani model za proračun stepena propuštanja pešaka u uslovima lokalnog odvijanja saobraćaja zavisi od protoka pešaka i vozila, strukture saobraćajnog toka (učešće autobusa i teretnih vozila) i smera kretanja vozila na lokaciji pešačkog prelaza. U okviru disertacije izvršena je analiza pešačkih intervala prilikom prelaska kolovoza. Uporednom analizom prihvatljivih i kritičnih intervala dobijen je model ponašanja pešaka u zavisnosti od karakteristika lokacije nesignalisanog pešačkog prelaza. Utvrđena je zavisnost između dužine prihvaćenih intervala pešaka prilikom prelaska kolovoza i uslova odvijanja saobraćaja, polnih karakteristika pešaka i broja pešaka koji prelaze kolovoz na nesignalisanom pešačkom prelazu.</p> / <p>The study, which was conducted within the thesis, has served to define a mathematical model that can be applied in the process of determining the level of service at unsignalized pedestrian crossings. The formed model for motorist yield rate, in terms of the local pedestrian traffic flow, depends on pedestrian and vehicular flow rate, traffic flow structure (the share of buses and freight vehicles), and vehicle moving at the location of a pedestrian crossing. The pedestrian gap acceptance behaviour has also been analysed. Comparative analysis of acceptable and critical pedestrian gap was conducted. Model of pedestrian behaviour, which depending on the site characteristics, was formed and it has been proven a correlation between the length of the accepted pedestrian gaps and the roadway and traffic conditions, gender characteristics and the number of pedestrians at unsignalized crossings.</p>
18

Konverze Heršpické ulice na sběrnou komunikaci / Conversion of Heršpická street to urban road

Mareček, Zdeněk January 2018 (has links)
The aim of this project is a refurbishment of the local collecting road Herspicka located in Brno, Czech republic. The goal of the project is to improve the accessibility for various transport means. The project contains design of several crossroads situated along this major road. This thesis is elaborated in a form of a technical study. The traffic flows intensity calculation was conducted on studied level crossings along the studied road.
19

Rekonstrukce ulice Roviny / Reconstruction of Roviny street

Tesáček, Svatopluk January 2013 (has links)
Within a range of study degree, the diploma thesis deals with a reconstruction design of three intersections and a single-span railway bridge along the Roviny street, Brno. The design is based on a familiarity with the territory as well as on traffic surveys. The proposed solution comprises the public transport lay-bys and pedestrians. The shape of intersections has been verified by means of vehicle-swept paths according to the TP 171 standard. The clearance under the bridge has been enlarged up to 4.80m and is in accordance with the S9.5 road category.
20

Přestupní uzel Brno - Merhautova / Transit Hub Brno - Merhautova

Krejčí, Petr January 2016 (has links)
The diploma thesis deals with the reconstruction of the intersection of streets Merhautova and Provazníkova in Brno in means of to establish a comfortable transit hub between all passing lines. The reconstruction of the intersection includes a proposal for new tram stops and adjustment of pedestrian routes allowing easy transfer between cruise lines, trolley buses and trams.

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