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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.
151

Cyclist Path Choices Through Shared Space Intersections in England

Duncan, Allison Boyce 11 March 2016 (has links)
In the last several years, there has been growing worldwide interest in making streets safer for all users--pedestrians, cyclists, and motorists. One approach, shared space, is a traffic calming technique as well as urban design concept. This technique strives to fully integrate the roadway into the urban fabric by removing elements such as lane markings, curbs, and traffic signs. By removing these elements and creating a more plaza-like space, these sites become ambiguous and no user group as priority. The technique is relatively new, and the majority of existing research concerns pedestrians only. This mixed methods research focused on six intersections in England with the goal of understanding how bicycle riders perceive and travel through shared space intersections. Using video observations of the six sites in three cities, three shared and three control, this project analyzed the variations in the paths cyclists rode through the intersections. Data were collected on several variables related to both the cyclists and their interactions with the site itself such as helmet use and riding through crosswalks. Path analysis required the development a new evaluative variable in order to compare individual paths by how much deviation there was in each path ridden as compared to other cyclists. Site-specific surveys addressed the perceptions, bicycling experience, demographics, and path and route preferences by cyclists at both shared space and control intersections. The analysis indicated that cyclists rode similarly through both shared and control intersections, and that a large percentage of riders preferred to ride farther from motor vehicles when given the space to do so. This project offered further insight in how to best design shared space projects for nonmotorized users by looking at the spatial layout and the elements that most influenced a rider’s path choice. Results indicated that, in these cases, shared space was not the panacea for nonmotorized users as some literature suggests, but nonetheless appeared to be a valid form of traffic calming. This research offered further insight in how to best design shared space projects for nonmotorized users by looking at the spatial layout and the elements that most influenced a rider’s path choice.
152

Bicyclist Compliance at Signalized Intersections

Thompson, Samson Ray Riley 30 March 2015 (has links)
This project examined cyclist red light running behavior using two data sets. Previous studies of cyclist compliance have investigated the tendencies of cyclists to run red lights on the whole by generalizing different maneuvers to their end outcome, running a red light. This project differentiates between the different types of red light running and focuses on the most egregious case, gap acceptance, which is when a cyclist runs a red light by accepting a gap in opposing traffic. Using video data, a mathematical model of cyclist red light running was developed for gap acceptance. Similar to other studies, this analysis utilized only information about the cyclist, intersection, and scenario that can be outwardly observed. This analysis found that the number of cyclists already waiting at the signal, the presence of a vehicle in the adjacent lane, and female sex were deterrents to red light running. Conversely, certain types of signal phasing, witnessing a violation, and lack of helmet increased the odds that a cyclist would run the red light. Interestingly, while women in general are less likely to run a red light, those who witnessed a violation were even more prone that men who had witnessed a violation to follow suit and run the red light themselves. It is likely that the differing socialization of women and men leads to different effects of witnessing a previous violator. The analysis also confirmed that a small subset of cyclists, similar to that found in the general population, are more prone to traffic violations. These cyclists are more willing to engage in multiple biking-related risk factors that include not wearing a helmet and running red lights. Although the model has definite explanatory power regarding decisions of cyclist compliance, much of the variance in the compliance choices of the sample is left unexplained. This points toward the influence of other, not outwardly observable variables on the decision to run a red light. Analysis of survey data from cyclists further confirms that individual characteristics not visible to the observer interact with intersection, scenario, and visible cyclist characteristics to result in a decision to comply (or not) with a traffic signal. Furthermore, cyclist characteristics, in general, and unobservable individual characteristics, specifically, play a larger role in compliance decisions as the number of compliance-inducing intersection traits (e.g. conflicting traffic volume) decrease. One such unobservable trait is the regard for the law by some cyclists, which becomes a more important determinant of compliance at simpler intersections. Cyclists were also shown to choose non-compliance if they questioned the validity of the red indication for them, as cyclists. The video and survey data have some comparable findings. For instance, the relationship of age to compliance was explored in both data analyses. Age was not found to be a significant predictor of non-compliance in the video data analysis while it was negatively correlated with stated non-compliance for two of the survey intersections. Gender, while having significant effects on non-compliance in the video dataset, did not emerge as an important factor in the stated non-compliance of survey takers. Helmet use had a consistent relationship with compliance between the video and survey datasets. Helmet use was positively associated with compliance in the video data and negatively associated with revealed non-compliance at two of the survey intersections. When coupled with the positive association between normlessness and stated willingness to run a red light, the relationship between helmet use and compliance solidifies the notion that a class of cyclists is more likely to consistently violate signals. It points towards a link between red light running and individuals who do not adhere to social norms and policies as strictly as others. Variables representing cyclists and motorists waiting at the signal were positively related to signal compliance in the video data. While an increased number of cyclists may be a physical deterrent to red light running, part of the influence on compliance that this variable and the variable representing the presence of a vehicle may be due to accountability of cyclists to other road users. This relationship, however, was not revealed in the stated non-compliance data from the survey. Efforts to increase cyclist compliance may not be worth a jurisdiction's resources since nearly 90% of cyclists in the video data were already compliant. If a problem intersection does warrant intervention, different methods of ensuring bicyclist compliance are warranted depending on the intersection characteristics. An alternative solution is to consider the applicability of traffic laws (originally designed for cars) to bicyclists. Creating separation in how laws affect motorists and cyclists might be a better solution for overly simple types of intersections where cyclists have fewer conflicts, better visibility, etc. than motorists. Education or other messaging aimed at cyclists about compliance is another strategy to increase compliance. Since cyclists appear to feel more justified in running red lights at low-volume, simple-looking intersections, it would probably be prudent to target messaging at these types of intersections. Many cyclists are deterred by high-volume and/or complicated looking intersections for safety reasons. Reminding cyclists of the potential dangers at other intersections may be a successful messaging strategy. Alternatively, reminding cyclists that it is still illegal to run a red light even if they feel safe doing so may be prudent. Additionally, messaging about the purpose of infrastructure such as bicycle-specific signals or lights that indicate detection at a signal may convince cyclists that stopping at the signal is in their best interest and that the wait will be minimal and/or warranted.
153

Transferability and Calibration of the Highway Safety Manual Performance Functions and Development of New Models for Urban four-lane Divided Roads

Al, Kaaf, Khalid 01 January 2014 (has links)
Many developing countries have witnessed fast and rapid growth in the last two decades due to the high development rate of economic activity in these countries. Many transportation projects have been constructed. In the same time both population growth and vehicle ownership rate increased; resulting in increasing levels of road crashes. Road traffic crashes in Gulf Cooperation Council (GCC) is considered a serious problem that has deep effects on GCC's population as well as on the national productivity through the loss of lives, injuries, property damage and the loss of valuable resources. From a recent statistical study of traffic crashes in Oman, it was found that in 2013 there were 7,829 crashes occurred for a total of 1,082,996 registered vehicles. These crashes have resulted in 913, 5591, and 1481 fatal, injury and property damage only crashes, respectively (Directorate General of Traffic, 2014), which is considered high rates of fatalities and injuries compared to other more developed countries. This illustrates the seriousness and dangerousness of the safety situation in GCC countries and Oman particularly. Thus, there is an urgent need to alleviate the Severity of the traffic safety problem in GCC which in turn will set a prime example for other developing countries that face similar problems. Two main data sources from Riyadh, the capital city of Kingdom of Saudi Arabia (KSA) and Muscat, the capital city of Sultanate of Oman have been obtained, processed, and utilized in this study. The Riyadh collision and traffic data for this study were obtained in the form of crash database and GIS maps from two main sources: the Higher Commission for the Development of Riyadh (HCDR) and Riyadh Traffic Department (RTD). The Muscat collision and traffic data were obtained from two main sources: the Muscat Municipality (MM) and Royal Oman Police, Directorate General of Traffic (DGC). Since the ARC GIS is still not used for traffic crash geocoding in Oman, the crash data used in the analysis were extracted manually from the filing system in the DGC. Due to the fact that not all developing countries highway agencies possess sufficient crash data that enable the development of robust models, this problem gives rise to the interest of transferability of many of the models and tools developed in the US and other developed nations. The Highway Safety Manual (HSM) is a prime and comprehensive resource recently developed in the US that would have substantial impact if researchers are able to transfer its models to other similar environment in GCC. It would save time, effort, and money. The first edition of the HSM provides a number of safety performance functions (SPFs), which can be used to predict collisions on a roadway network. This dissertation examined the Transferability of HSM SPFs and developing new local models for Riyadh and Muscat. In this study, first, calibration of the HSM SPFs for Urban Four-lane divided roadway segments (U4D) with angle parking in Riyadh and the development of new SPFs were examined. The study calibrates the HSM SPFs using HSM default Crash Modification Factors (CMFs), then new local CMFs is proposed using cross-sectional method, which treats the estimation of calibration factors using fatal and injury data. In addition, new forms for specific SPFs are further evaluated to identify the best model using the Poisson-Gamma regression technique. To investigate how well the safety performance model fits the data set, several performance measures were examined. The performance measures summarize the differences between the observed and predicted values from related SPFs. Results indicate that the jurisdiction-specific SPFs provided the best fit of the data used in this study, and would be the best SPFs for predicting severe collisions in the City of Riyadh. The study finds that the HSM calibration using Riyadh local CMFs outperforms the calibration method using the HSM default values. The HSM calibration application for Riyadh crash conditions highlights the importance to address variability in reporting thresholds. One of the findings of this research is that, while the medians in this study have oversize widths ranging from 16ft-70ft, median width has insignificant effect on fatal and injury crashes. At the same time the frequent angle parking in Riyadh urban road networks seems to increase the fatal and injury collisions by 52 percent. On the other hand, this dissertation examined the calibration of the HSM SPFs for Urban intersections in Riyadh, Kingdom of Saudi Arabia (KSA) and the development of new set of models using three year of collision data (2004-2006) from the city of Riyadh. Three intersection categories were investigated: 3-leg signalized, 4-leg signalized, and 3-leg unsignalized. In addition, new forms for specific SPFs are further evaluated to identify the best model using the Poisson-Gamma regression technique. Results indicate that the new local developed SPFs provided the best fit of the data used in this study, and would be the best SPFs for predicting severe crashes at urban intersections in the City of Riyadh Moreover, this study examined the calibration of the HSM SPFs for Fatal and Injury (FI), Property Damage Only (PDO) and total crashes for Urban Four-lane divided roadway segments (U4D) in Muscat, Sultanate of Oman and the development of new SPFs. This study first calibrates the HSM SPFs using the HSM methodology, and then new forms for specific SPFs are further evaluated for Muscat's urban roads to identify the best model. Finally, Riyadh fatal and injury model were validated using Muscat FI dataset. Comparisons across the models indicate that HSM calibrated models are superior with a better model fit and would be the best SPFs for predicting collisions in the City of Muscat. The best developed collision model describes the mean crash frequency as a function of natural logarithm of the annual average daily traffic, segment length, and speed limit. The study finds that the differences in road geometric design features and FI collision characteristics between Riyadh and Muscat resulted in an un-transferable Riyadh crash prediction model. Overall, this study lays an important foundation towards the implementation of HSM methods in multiple cities (Riyadh and Muscat), and could help their transportation officials to make informed decisions regarding road safety programs. The implications of the results are extendible to other cities and countries and the region, and perhaps other developing countries as well.
154

Pedestrian Walking Speeds at Signalized Intersections in Utah

Berrett, Jordi Jordan 01 March 2019 (has links)
The 2009 edition of the Manual on Uniform Traffic Control Devices (MUTCD) recommends a pedestrian walking speed of 3.5 feet per second for use in the timing of pedestrian clearance intervals at signalized intersections (reduced from 4.0 feet per second in the 2003 edition). Jurisdictions across the state of Utah continue to maintain pedestrian walking speeds of 4.0 feet per second for normal intersections with guidance on engineering judgement for areas where a lower pedestrian walking speed should be considered. In 2018, it was decided that the current state guidance with regard to pedestrian walking speeds be evaluated for any needed changes, such as adopting the national guidance found in the 2009 MUTCD. To evaluate pedestrian walking speeds at signalized intersections, 15 sites throughout the state of Utah were studied, producing a total of 2,061 observations of pedestrian crossing events. These crossing events were evaluated to calculate walking speeds in relation to pedestrian demographics at each location. Evaluated demographics included pedestrian group size, gender, mobility status, age category, alertness, and potential distractions. Upon completion of data collection, a statistical analysis was conducted to determine mean and 15th percentile pedestrian walking speeds by demographic. The data collection procedure, data analysis, and limited recommendations for pedestrian start-up delay and pedestrian walking speeds as used in signal timing are discussed in this report. The data suggest that Utah continue to maintain its guidance of 4.0 feet per second walking speeds at most signalized intersections, while exercising engineering judgment at locations containing high pedestrian volumes or locations containing high percentages of elderly or disabled pedestrians.
155

SAFER WALKING ROUTES TO SCHOOL: APPLIED AND METHODOLOGICAL GEOGRAPHIES OF CHILD PEDESTRIAN INJURY

Bennet, Scott A. 11 1900 (has links)
The study area for this dissertation is Hamilton, Ontario, Canada. / The general theme of this dissertation is understanding and enabling safe walking routes to school for children. We restrict our focus to safety issues related to the motorized-transportation environment, thereby defining safety as a function of factors that determine whether or not a child will be struck by a motor-vehicle on their journey to or from school. Our analysis is unique because it is at a small geographical scale but is representative of an entire urban environment. Working at a small geographic scale allows us to evaluate the variability in safe routes for children within our study area and apply our findings to develop a decision support tool that could be used to plan individualized routes for children in other similar urban environments. Our study area for this dissertation is Hamilton, Ontario, Canada. The findings in this dissertation contribute ideas about how features of the local road environment may and may not influence risk of collisions between child pedestrians and motor-vehicles. It also offers methodological insight for future research on pedestrian safety at small geographic scales. This dissertation demonstrates the potential reduction in the risk of child pedestrian injuries by planning safer routes to school and also introduces methods that can be used to plan safer routes for children. Our results are a reminder of the importance of understanding the interaction between environment and behaviour in research on traffic safety and offer some caution to the notion of a universal 'safe route' to school. Whether or not a particular route to school is safe will very likely be dependent both on the environment and the child's behaviour in that environment. / Dissertation / Doctor of Social Science
156

Intersecting Identities: Race and Gender in a Quinceañera Fashion Show

Serrano, Tamara E. 31 July 2009 (has links)
No description available.
157

Evaluación y propuesta para optimizar flujo vehicular en intersección de avenidas Chinchaysuyo con Fitzcarrald y Víctor Raúl Haya de la Torre en provincia de Chiclayo 2021

Nuñez Constantino, Darwin Marino January 2024 (has links)
A lo largo de los años ha sido notorio el incremento de vehículos en el Perú, de igual manera en sus ciudades y este proyecto se desarrolla en la provincia de Chiclayo, precisamente en una intersección vial muy concurrida entre la avenida Chinchaysuyo con avenida Fitzcarrald y la avenida Víctor Raúl Haya de la Torre. En dicha intersección se genera congestión vehicular, esto se puede evidenciar en las colas de vehículos y la excesiva demora que se generan paracruzar una avenida sobre todo en horas punta. Teniendo en cuenta esta problemática y enfocando a la Ingeniería de Tránsito, la cual busca una planificación, diseño y principalmente busca una solución para mejorar el flujo vehicular. La investigación se centrará en analizar dicha intersección, elaborar un estudio de tráfico, levantamiento topográfico, con estos estudios se elabora un nuevo diseño geométrico, con esto también se hace una simulación vehicular. Al resultado de todos los datos se evaluarán dos propuestas y se determinara cual es la más conveniente para dicha intersección y se elaborara un modelamiento elaborando el programa de simulación Synchro 8. / Throughout the years, the increase in vehicles has been notorious in Peru, in the same way in its cities and this project is developed in the province of Chiclayo, precisely in a very busy road intersection between Chinchaysuyo avenue with Fitzcarrald avenue and Víctor Raul avenue. Haya de la Torre. In this intersection, traffic congestion is generated, this can be evidenced in the queues of vehicles and the excessive delay that is generated to cross an avenue, especially at peak times. Taking into account this problem and focusing on Traffic Engineering, which seeks planning, design and mainly seeks a solution to improve traffic flow. The research will focus on analyzing said intersection, developing a traffic study, topographic survey, with these studies a new geometric design is developed, with this a vehicular simulation is also made. At the result of all the data, two proposals will be evaluated and it will be determined which is the most convenient for said intersection and a modeling will be elaborated using the Synchro 8 simulation program.
158

De l'impact d'une décision locale et autonome sur les systèmes de transport intelligent à différentes échelles / The impact of local and autonomous decision on intelligent transport systems at different scales

Lebre, Marie-Ange 25 January 2016 (has links)
Cette thèse présente des applications véhiculaires à différentes échelles : de la petite qui permet d'effectuer des tests réels de communication et de service ; à des plus grandes incluant plus de contraintes mais permettant des simulations sur l'ensemble du réseau. Dans ce contexte nous soulignons l'importance d'avoir et de traiter des données réelles afin de pouvoir interpréter correctement les résultats. A travers ces échelles nous proposons différents services utilisant la communication V2V et V2I. Nous ne prétendons pas prendre le contrôle du véhicule, notre but est de montrer le potentiel de la communication à travers différents services. La petite échelle se focalise sur un service à un feu de circulation permettant d'améliorer les temps de parcours et d'attente, et la consommation en CO2 et en carburant. La moyenne échelle se situant sur un rond-point, permet grâce à un algorithme décentralisé, d'améliorer ces mêmes paramètres, mais montre également qu'avec une prise de décision simple et décentralisée, le système est robuste face à la perte de paquet, à la densité, aux comportements humains ou encore aux taux d'équipement. Enfin à l'échelle d'une ville, nous montrons que grâce à des décisions prises de manière locale et décentralisée, avec seulement un accès à une information partielle dans le réseau, nous obtenons des résultats proches des solutions centralisées. La quantité de données transitant ainsi dans le réseau est considérablement diminuée. Nous testons également la réponse de ces systèmes en cas de perturbation plus ou moins importante tels que des travaux, un acte terroriste ou une catastrophe naturelle. Les modèles permettant une prise de décision locale grâce aux informations délivrées autour du véhicule montrent leur potentiel que se soit avec de la communication avec l'infrastructure V2I ou entre les véhicules V2V. / In this thesis we present vehicular applications across different scales: from small scale that allows real tests of communication and services; to larger scales that include more constraints but allowing simulations on the entire network. In this context, we highlight the importance of real data and real urban topology in order to properly interpret the results of simulations. We describe different services using V2V and V2I communication. In each of them we do not pretend to take control of the vehicle, the driver is present in his vehicle, our goal is to show the potential of communication through services taking into account the difficulties outlined above. In the small scale, we focus on a service with a traffic light that improves travel times, waiting times and CO2 and fuel consumption. The medium scale is a roundabout, it allows, through a decentralized algorithm, to improve the same parameters. It also shows that with a simple and decentralized decision-making process, the system is robust to packet loss, density, human behavior or equipment rate. Finally on the scale of a city, we show that local and decentralized decisions, with only a partial access to information in the network, lead to results close to centralized solutions. The amount of data in the network is greatly reduced. We also test the response of these systems in case of significant disruption in the network such as roadworks, terrorist attack or natural disaster. Models, allowing local decision thanks to information delivered around the vehicle, show their potential whatsoever with the V2I communication or V2V.
159

Quantum dynamics and laser control for photochemistry / Dynamique quantique et contrôle par laser pour la photochimie

Sala, Matthieu 08 April 2015 (has links)
Cette thèse porte sur la description théorique de processus dynamiques ultra-rapides de molécules polyatomiques et de leur contrôle par impulsions laser. Nous avons d’abord étudié la photochimie de l’aniline à l’aide de calculs de structure électronique. Nous avons d´écrit plusieurs régions clé des surfaces d’énergie potentielle et analysé ces résultats en relation avec les données expérimentales existantes. La photochimie de la pyrazine a été étudiée par des calculs de dynamiques quantique basés sur un Hamiltonien modèle incluant les quatre états électroniques excités de plus basse énergie et seize modes de vibration. Nous montrons que l’état sombre Au(nπ∗) joue un rôle important dans la dynamique de la molécule après photo-excitation. Un modèle simplifié à deux états et quatre modes a été utilisé pour étudier le contrôle par laser de la dynamique de la pyrazine photo-excitée. Nous proposons un mécanisme visant à augmenter la durée de vie de l’état B2u(ππ∗) en utilisant l’effet Stark induit par une impulsion laser intense non-résonante. / The central subject of this thesis is the theoretical description of ultrafast dynamical processes in molecular systems of chemical interest and of their control by laser pulses. We first use electronic structure calculations to study the photochemistry of aniline. A umber of previously unknown features of the potential energy surfaces of the low-lying elec-tronic states are reported, and analyzed in relation with the experimental results available. We use quantum dynamics simulations, based on a model Hamiltonian including the four lowest excited electronic states and sixteen vibrational modes, to investigate the photochem-istry of pyrazine. We show that the dark Au(nπ∗) state plays an important role in the ultrafast dynamics of the molecule after photoexcitation. The laser control of the excited state dynamics of pyrazine is studied using a simplified two-state four-mode model Hamiltonian. We propose a control mechanism to enhance the lifetime of the bright B2u(ππ∗) state using the Stark effect induced by a strong non-resonant laser pulse. We finally focus on the laser control of the tunneling dynamics of the NHD2 molecule, using accurate full-dimensional potential energy and dipole moment surfaces. We use simple effective Hamiltonians to explore the effect of the laser parameters on the dynamics and design suitable laser fields to achieve the control. These laser fields are then used in MCTDH quantum dynamics simulations. Both enhancement and suppression of tunneling are achieved in our model.
160

Situation Assessment at Intersections for Driver Assistance and Automated Vehicle Control

Streubel, Thomas 20 January 2016 (has links)
The development of driver assistance and automated vehicle control is in process and finds its way more and more into urban traffic environments. Here, the complexity of traffic situations is highly challenging and requires system approaches to comprehend such situations. The key element is the process of situation assessment to identify critical situations in advance and derive adequate warning and intervention strategies. This thesis introduces a system approach to establish a situation assessment process with the focus on the prediction of the driver intention. The system design is based on the Situation Awareness model by Endsley. Further, a prediction algorithm is created using Hidden Markov Models. To define the parameters of the models, an existing database is used and previously analyzed to identify reasonable variables that indicate an intended driving direction while approaching the intersection. Here, vehicle dynamics are used instead of driver inputs to enable a further extension of the prediction, i.e.\\ to predict the driving intention of other vehicles detected by sensors. High prediction rates at temporal distances of several seconds before entering the intersection are accomplished. The prediction is integrated in a system for situation assessment including an intersection model. A Matlab tool is created with an interface to the vehicle CAN bus and the intersection modeling which uses digital map data to establish a representation of the intersection. To identify differences and similarities in the process of approaching an intersection dependent on the intersection shape and regulation, a naturalistic driving study is conducted. Here, the distance to the intersection and velocity is observed on driver inputs related to the upcoming intersection (leaving the gas pedal, pushing the brake, using the turn signal). The findings are used to determine separate prediction models dependent on shape and regulation of the upcoming intersection. The system runs in real-time and is tested in a real traffic environment.:Contents List of Figures Acronyms 1 Introduction 1.1 Motivation 1.2 Outline 2 Fundamentals 2.1 Traffic Intersections 2.2 Situation Assessment 2.3 Prediction of Driver Intention 2.3.1 Methods Overview 2.3.2 Hidden Markov Models 2.4 Localization 3 Driving Behavior 3.1 Data Analysis 3.1.1 Data selection and processing 3.1.2 Results 3.1.3 Conclusion 3.2 Naturalistic Driving Study 3.2.1 Background 3.2.2 Methods 3.2.3 Results 3.2.4 Discussion and Conclusion 4 Prediction Algorithm 4.1 Framework 4.2 Input data 4.3 Evaluation 4.4 Validation 4.5 Conclusion 5 System Approach 5.1 Sensing 5.2 Situation analysis 5.3 Prediction 5.3.1 Implementation 5.3.2 Graphical User Interface (GUI) 5.3.3 Testing and Outlook 6 Conclusion and Outlook Bibliography / Die Entwicklung von Fahrerassistenz und automatisiertem Fahren ist in vollem Gange und entwickelt sich zunehmend in Richtung urbanen Verkehrsraum. Hier stellen besonders komplexe Verkehrssituationen sowohl für den Fahrer als auch für Assistenzsysteme eine Herausforderung dar. Zur Bewältigung dieser Situationen sind neue Systemansätze notwendig, die eine Situationsanalyse und -bewertung beinhalten. Dieser Prozess der Situationseinschätzung ist der Schlüssel zum Erkennen von kritischen Situationen und daraus abgeleiteten Warnungs- und Eingriffsstrategien. Diese Arbeit stellt einen Systemansatz vor, welcher den Prozess der Situationseinschätzung abbildet mit einem Fokus auf die Prädiktion der Fahrerintention. Das Systemdesign basiert dabei auf dem Situation Awareness Model von Endsley. Der Prädiktionsalgorithmus ist mit Hilfe von Hidden Markov Modellen umgesetzt. Zur Bestimmung der Modellparameter wurde eine existierende Datenbasis genutzt und zur Bestimmung von relevanten Variablen für die Prädiktion der Fahrtrichtung während der Kreuzungsannäherung analysiert. Dabei wurden Daten zur Fahrdynamik ausgewählt anstelle von Fahrereingaben um die Prädiktion später auf externe Fahrzeuge mittels Sensorinformationen zu erweitern. Es wurden hohe Prädiktionsraten bei zeitlichen Abständen von mehreren Sekunden bis zum Kreuzungseintritt erzielt. Die Prädiktion wurde in das System zur Situationseinschätzung integriert. Weiterhin beinhaltet das System eine statische Kreuzungsmodellierung. Dabei werden digitale Kartendaten genutzt um eine Repräsentation der Kreuzung und ihrer statischen Attribute zu erzeugen und die der Kreuzungsform entsprechenden Prädiktionsmodelle auszuwählen. Das Gesamtsystem ist als Matlab Tool mit einer Schnittstelle zum CAN Bus implementiert. Weiterhin wurde eine Fahrstudie zum natürlichen Fahrverhalten durchgeführt um mögliche Unterschiede und Gemeinsamkeiten bei der Annäherung an Kreuzungen in Abhängigkeit der Form und Regulierung zu identifizieren. Hierbei wurde die Distanz zur Kreuzung und die Geschwindigkeit bei Fahrereingaben im Bezug zur folgenden Kreuzung gemessen (Gaspedalverlassen, Bremspedalbetätigung, Blinkeraktivierung). Die Ergebnisse der Studie wurden genutzt um die Notwendigkeit verschiedener Prädiktionsmodelle in Abhängigkeit von Form der Kreuzung zu bestimmen. Das System läuft in Echtzeit und wurde im realen Straßenverkehr getestet.:Contents List of Figures Acronyms 1 Introduction 1.1 Motivation 1.2 Outline 2 Fundamentals 2.1 Traffic Intersections 2.2 Situation Assessment 2.3 Prediction of Driver Intention 2.3.1 Methods Overview 2.3.2 Hidden Markov Models 2.4 Localization 3 Driving Behavior 3.1 Data Analysis 3.1.1 Data selection and processing 3.1.2 Results 3.1.3 Conclusion 3.2 Naturalistic Driving Study 3.2.1 Background 3.2.2 Methods 3.2.3 Results 3.2.4 Discussion and Conclusion 4 Prediction Algorithm 4.1 Framework 4.2 Input data 4.3 Evaluation 4.4 Validation 4.5 Conclusion 5 System Approach 5.1 Sensing 5.2 Situation analysis 5.3 Prediction 5.3.1 Implementation 5.3.2 Graphical User Interface (GUI) 5.3.3 Testing and Outlook 6 Conclusion and Outlook Bibliography

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