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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

Effects of Connected Vehicle Technology on Mobility and Mode Choice

Minelli, Simon 11 1900 (has links)
Connected vehicle is a fully connected transportation system in which vehicles, infrastructure, and mobile devices are enabled to exchange information in real-time to bring advancements in transportation operations. It is important to incorporate the new characteristics of the connected vehicle in the transportation planning process. Also, it is vital for planning and road agencies to better understand the impacts of connected vehicle on transportation networks, system demand, and travel behavior of road users in order to properly prepare for them. In addition, developers of connected vehicle systems can gain insight into how their systems will impact road users and network performance. When a change in performance of a transportation network occurs it can potentially cause users to change travel modes, known as mode choice. In this research, the change in mode choice, due to the change in network performance by introduction of connected vehicle is studied. This provides a more accurate depiction of the performance of the network and indicates how connected vehicles could change travellers’ preference in travel mode. The effect of this technology is explored on the performance of the Toronto waterfront, in a microsimulation environment. The results show that average travel time increases for high market penetrations when a dynamic route guidance algorithm is implemented, a phenomenon that occurs in dense, and complex traffic networks. Analysis of mode choice shows a loss in the auto mode share, for high market penetrations, due to the increased auto travel times. This loss in the auto mode share is compensated by increases in the other modes. / Thesis / Master of Applied Science (MASc)
12

Assessment of Vehicle-to-Vehicle Communication based Applications in an Urban Network

Kim, Taehyoung 23 June 2015 (has links)
Connected Vehicle research has emerged as one of the highest priorities in the transportation systems because connected vehicle technology has the potential to improve safety, mobility, and environment for the current transportation systems. Various connected vehicle based applications have been identified and evaluated through various measurements to assess the performance of connected vehicle applications. However, most of these previous studies have used hypothetical study areas with simple networks for connected vehicle environment. This study represents connected vehicle environment in TRANSIMS to assess the performance of V2V communication applications in the realistic urban network. The communication duration rate and spatial-temporal dispersion of equipped vehicles are investigated to evaluate the capability of V2V communication based on the market penetration rate of equipped vehicles and wireless communication coverage in the whole study area. The area coverage level is used to assess the spatial-temporal dispersion of equipped vehicles for two study areas. The distance of incident information propagation and speed estimation error are used to measure the performance of event-driven and periodic applications based on different market penetration rates of equipped vehicles and wireless communication coverage in both morning peak and non-peak times. The wireless communication coverage is the major factor for event-driven application and the market penetration rate of equipped vehicles has more impact on the performance of periodic application. The required minimum levels of deployment for each application are determined for each scenario. These study findings will be useful for making decisions about investments on deployment of connected vehicle applications to improve the current transportation systems. Notably, event-driven applications can be reliably deployed in the initial stage of deployment despite the low level of market penetration of equipped vehicles. / Ph. D.
13

A Clustering-based Multi-channel Vehicle-to-Vehicle (V2V) Communication System

Ding, Ranran 09 April 2010 (has links)
No description available.
14

Driver Safety Alert System - An Alternative to Vehicle-to-Vehicle Communication-based Systems

Weston, Leigh, Marrero Reyes, Javier January 2016 (has links)
Automotive transport unavoidably raises safety concerns for drivers, passengers, and indeed, all road users alike. Advancements in vehicle safety technologies have come a long way, and have had a major impact on the reduction of road-related accidents and fatalities. However, as the push towards autonomous vehicle systems gains momentum, assumptions must be avoided about the global application of such technologies.This paper proposes an idea for a road safety alert system, which is realized in the form of small-scale prototype, subsequently tested and evaluated to study its theoretical application to real world scenarios. The system is geared towards developing regions of the world where a reduction in road-related accidents and death is needed most. Reviews of various existing and proposed safety systems within the realm of Intelligent Transportation Systems (ITS) are conducted, with a focus on Vehicle-to-Vehicle (V2V) and non-V2V applications, which are compared to and contrasted with our proposal.We hope to foster further discussion and research into suitable technologies and their application, in regions of the world that require a different approach when trying to realistically reduce the consistent destructive trend of accidents and fatalities when humans are still behind the wheel.
15

Intersection Simulation and Path Estimation

Milo, Curtis January 2020 (has links)
As autonomous vehicles begin to move towards full autonomy, the controllers and software within them are becoming incredibly more complex to deal with any plausible scenario. Automotive manufacturers must balance the need for safety with the customers' desire for performance and features. A robust set of tools is a necessity to develop vehicle control protocols and navigation strategies. Vehicle to everything communication protocols and path planning are two aspects of autonomous vehicles that need a large amount of development effort. The MathWorks has put a great amount of effort in developing a robust simulation tool for autonomous vehicles. However, it currently lacks a method to develop V2X communication and path routing. In this thesis, I developed an extension for the Mathworks Simulink autonomous driving toolbox to incorporate graph-based path planning and vehicle to vehicle communication. The navigation system models each road using standard civil engineering techniques, to calculate the intersection points and bounding areas for regions of interest. Based on these regions, a directed graph is created to aid in calculating the shortest path. The navigation system also provides a redundant method for path planning for poorly marked areas and intersections. The vehicle to vehicle communication system emulates the 802.11p protocol and deals with practical challenges such as latency to provide developers with a realistic environment in which to develop vehicle communication protocols. The final result is a simulation where multiple vehicles drive safely and efficiently throughout a city network, sending messages at regions of interest and follow computed paths to their desired destinations. / Thesis / Master of Applied Science (MASc) / Vehicle to Everything communication protocols and path planning are two aspects of autonomous vehicles that need a robust framework to aid in their development. I developed an extension for the Mathworks Simulink autonomous driving toolbox to incorporate graph-based path planning and vehicle to vehicle communication. The navigation system models each road using standard civil engineering techniques, to calculate the intersection points and bounding areas for regions of interest. Based on these regions, a directed graph is created to aid in calculating the shortest path. The navigation system also provides a redundant method for path planning for poorly marked areas and intersections. The vehicle to vehicle communication system emulates the 802.11p protocol and realistic effects such as latency to provide developers with a realistic environment to develop vehicle communication protocols. The final result is a simulation where multiple vehicles drive throughout a city network, sending messages at regions of interest and follow a computed path to their desired destination.
16

Applications of Connected Vehicle Technology to Address Issues of School Bus and School Bus Stop Safety

Donoughe, Kelly 01 March 2016 (has links)
An analysis of crash data shows that the number of fatal school bus related crashes has remained nearly constant over the past ten years, despite an increase in available safety-improving technology. One of the main concerns related to school bus safety is the issue of illegally passing a stopped school bus. To improve safety around stopped school buses, this dissertation presents a Concept of Operations for a connected vehicle application to improve safety around stopped school buses using Dedicated Short Range Communication. The focus of this application is to increase awareness of stopped school buses or bus stops that are obscured from the driver's view. An on-road naturalistic driving experiment evaluated driver response to an in-vehicle message to warn drivers that they were approaching a school bus that was stopped around a curve. The dissertation concludes by using microsimulation to evaluate the impact of implementing specialized speed control algorithms to reduce vehicle speeds near bus stops along high speed roads. The simulation evaluated the effect of the reduce speed zone on travel time and emissions when the system was considered as a pre-timed speed limit and also when the system was modeled as a connected vehicle system. / Ph. D.
17

Aufbau und Bewertung eines mobilen Messwerterfassungssystems

Häberlein, Tim 18 April 2024 (has links)
Durch die große Anzahl moderner Fahrzeugfunktionen entsteht ein hohes internes Datenaufkommen. Um die im Fahrzeug anfallende Datenmengen filtern und zentral verarbeiten zu können, müssen entsprechende Telemetrie-Systeme aufgebaut und erweitert werden können. Die vorliegende Arbeit beschäftigt sich mit dem Ausbau einer vorhandenen Telemetrieeinheit zu einem verteilten Regelsystem mit weicher Echtzeitanforderung bei vorgegebener Messtechnik und Messsoftware. Anhand einer MATLAB/Simulink Temperatur-Simulation werden die Auswirkungen und das Potenzial einer verteilten Regelung, für einen einfachen Anwendungsfall, aufgezeigt. Um Gütekriterien für via Mobilfunk verteilte Fahrzeugfunktionen abschätzen zu können, werden systembedingte Verzögerungszeiten für verschiedene Fahrstrecken untersucht. Das konzipierte Validierungsmodell bestätigt die Untersuchungen. / Current car and truck electronics are made up of a huge number of electronic controllers. As a result of this, a lot of data traffic needs to be managed internally. In Addition, this specific data gives the chance to interact with other cars or traffic systems. The resulting BIG DATA flow needs to be sorted and distributed via so-called “automotive telematics units”. To remodel and to extend these functions, new solutions have to be provided. Considering that measurement software and hardware are provided, this paper shows how an existing telematics system is able to create a distributed control system which fulfills soft real-time requirements. Using a simple case-study, a MATLAB/Simulink temperature-simulation presents the effects and the potential of such a control. To indicate quality criteria for distributed vehicle functions (via cellular network), system-related delay times for different routes are analyzed. Finally, the designed validation-model affirms the approach.
18

Probability Distribution of Rician K-Factor in Urban, Suburban and Rural Areas Using Real World Captured Data

Abd-Alhameed, Raed, Jones, Steven M.R., Noras, James M., Zhu, Shaozhen (Sharon), Ghazaany, Tahereh S., Van Buren, T., Wilson, J., Suggett, T., Marker, S. 07 1900 (has links)
Yes / The Rician K-factor of the vehicle-to-vehicle (V2V) wireless propagation channel is estimated using a moment-based method on the envelope of measured pulse data. The measurements were carried out under vehicle-to-vehicle wireless communication channel condition with car rooftop antenna heights at one end of the link and very low antenna height at the other end. Data captured from typical urban, suburban and rural areas are analyzed and the K-factor probability density function is generated for each scenario to give an insight into the V2V channel behavior. For all three areas, the majority of K values are found to be within the range of -10 to +10 dB. The K-factor distributions are close to normal with mean values of 1.8, 2.6 and 3 dB respectively for urban, suburban and rural area.
19

Κατανεμημένος έλεγχος κυκλοφορίας με σκοπό τη βελτιστοποίηση των συνθηκών ασφάλειας

Θεοδοσίου, Ιωάννης, Μπάλλας, Κωνσταντίνος 15 December 2014 (has links)
Σκοπός αυτής της διπλωματικής εργασίας είναι να αναπτυχθεί ένα μοντέλο αποφυγής συγκρόυσεων μεταξύ των οχημάτων μέσω της επικοινωνίας αυτών. Το σύστημα αυτό θα πρέπει να αναγνωρίζει τις περιπτώσεις που εγκυμονούν κίνδυνο μέσω της ανταλλαγής μηνυμάτων από τα οχήματα κάθε χρονική στιγμή και μέσα από διάφορους μηχανισμούς που επιτελούνται από αυτό, τελικά, να επεμβαίνει και να αποτρέπει τη σύγκρουση ή να ειδοποιεί τον οδηγό ώστε αυτός να αντιδράσει εγκαίρως. Για να το πετύχουμε αυτό ακολουθήσαμε τα εξής βήματα: 1. Προσομοιώσαμε τη λειτουργία μίας συσκευής GPS. 2. Σχεδιάσαμε λεκτικά και γραφικά τα μοντέλα κίνησης στα οποία θα τρέχει το σύστημά μας. 3. Ορίσαμε ένα πρωτόκολλο ανταλλαγής μηνυμάτων και προειδοποίησης σε περίπτωση συγκρουσης για αυτά τα μοντέλα κίνησης. 4. Αναπτύξαμε το σύστημα μέσω της matlab, λαμβάνοντας υπόψιν το πρωτόκολλο και τα σενάρια κίνησης των προηγούμενων βημάτων. 5. Κατασκευάσαμε μία διεπαφή εποπτίας και ελέγχου όλου του συστήματος. 6. Τέλος, κατασκευάσαμε ένα GUI ειδοποίησης του οδηγού σε περιπτώσεις κινδύνου. / Distributed traffic Control for Optimisation of the Safety Conditions.
20

Concept of an enhanced V2X pedestrian collision avoidance system with a cost function–based pedestrian model

Kotte, Jens, Schmeichel, Carsten, Zlocki, Adrian, Gathmann, Hauke, Eckstein, Lutz 29 September 2020 (has links)
Objective: State-of-the-art collision avoidance and collision mitigation systems predict the behavior of pedestrians based on trivial models that assume a constant acceleration or velocity. New sources of sensor information—for example, smart devices such as smartphones, tablets, smartwatches, etc.—can support enhanced pedestrian behavior models. The objective of this article is the development and implementation of a V2Xpedestrian collision avoidance system that uses new information sources. Methods: A literature review of existing state-of-the-art pedestrian collision avoidance systems, pedestrian behavior models in advanced driver assistance systems (ADAS), and traffic simulations is conducted together with an analysis of existing studies on typical pedestrian patterns in traffic. Based on this analysis, possible parameters for predicting pedestrian behavior were investigated. The results led to new requirements from which a concept was developed and implemented. Results: The analysis of typical pedestrian behavior patterns in traffic situations showed the complexity of predicting pedestrian behavior. Requirements for an improved behavior prediction were derived. A concept for a V2X collision avoidance system, based on a cost function that predicts pedestrian near future presence, and its implementation is presented. The concept presented considers several challenges such as information privacy, inaccuracies of the localization, and inaccuracies of the prediction. Conclusion: A concept for an enhanced V2X pedestrian collision avoidance system was developed and introduced. The concept uses new information sources such as smart devices to improve the prediction of the pedestrian's presence in the near future and considers challenges that come along with the usage of these information sources.

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