Thesis (MEng)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: Peak mornmg traffic-flow data were obtained from video footage of three representative freeway sections on the Nl and N2 westbound towards Cape Town. Flow, speed, and density measurements were made from the footage with the aid of a stopwatch. Many researchers (2-12) have originated and developed models to describe the relationships between traffic flow characteristics (speed, flow, and density) on freeways. In this report, a number of these models have been investigated with data obtained from South African freeways. The ability of each model to predict flow parameters over the entire range of data was evaluated with the aid of statistical methods. The tests were performed by regressing average speed vs. average density. Flow-density and speed-flow relationships were derived through application of the steady-state equation (2.6). In each case, a final model was chosen through visual inspection that consisted of two separate curves, one for the uncongested flow regime and one for the congested flow regime. Furthermore, speed-flow relationships were examined for individual lanes and compared to relationships established for average lanes. The models were also compared to models obtained from overseas studies (1,16,19) as well as from studies done locally (17). A secondary objective of this study is to investigate the performance of existing freeway facilities through application of the relevant models to the traffic-flow data of a particular facility. The current peak-morning performance of the N2 freeway section is investigated in terms of travel-time and travel cost. The particular study section consists of three lanes, the right hand lane being an HOY lane dedicated to taxis and buses. Different hypothetical cases are investigated. The first hypothetical case is an investigation into the traffic situation on the freeway section without the influence of the HOY lane. The second hypothetical case investigates the traffic situation on the section with perfect operation of the HOY lane. The current performance of the N2 section is compared to the performance of each of the hypothetical cases. / AFRIKAANSE OPSOMMING: Oggend-spits verkeersvloei data is verkry vanaf drie verteenwoordigende seksies op die Nl en N2 deurpaaie naby Kaapstad met die gebruik van 'n video kamera. Vloei, spoed, end digtheid opnames is gemaak met behulp van 'n stophorlosie. Verskeie navorsers (2-12) het modelle gepostuleer en ontwikkelom die verhoudings tussen verkeersvloei eienskappe (spoed, volume, en digtheid) op deurpaaie te beskryf. In hierdie verslag word 'n aantal van hierdie modelle ondersoek met data wat verkry is van Suid-Afrikaanse deurpaaie. Die vermoë van elke model om vloei eienskappe oor die hele bestek van die data te voorspel is geëvalueer met behulp van statistiese metodes. Statistiese toetse behels 'n regressie analise van gemiddelde spoed teenoor gemiddelde digtheid. Volume-digtheid en spoed-volume verwantskappe is direk afgelei vanaf Vergelyking 2.6. Vir elke geval is 'n finale model m.b.v. visuele inspeksie gekies wat bestaan het uit twee afsonderlike kurwes, een kurwe vir die vryvloei regime en 'n ander kurwe vir hoë-digtheid toestande. Verder word spoedvolume verwantskappe vir afsonderlike deurpad-lane ondersoek en vergelyk met verwantskappe wat verkry is vir gemiddelde lane. Die modelle word ook vergelyk met modelle wat verkry is vanaf oorsese studies (1,16,19), sowel as met modelle wat plaaslik verkry is (17). 'n Sekondêre doel van hierdie studie is om die prestasie van bestaande deurpadfasiliteite te ondersoek deur die verskillende modelle aan te wend tot die verkeersvloei data van 'n betrokke fasiliteit. Die prestasie van die N2 deurpad seksie gedurende oggend-spits verkeer is ondersoek in terme van reistyd en ryskoste. Die betrokke seksie bestaan uit drie lane, waarvan die regter laan gereserveer is vir busse en taxis. Verskeie hipoteses is ook ondersoek. Die eerste hipotese is 'n ondersoek na die verkeers-vloei kondisie op die seksie sonder die invloed van die bus- en taxi-laan. Die tweede hipotese ondersoek die seksie met perfekte werking van die bus- en taxilaan. Die huidige prestasie van die N2 seksie is vergelyk met die prestasie van elk van die hipoteses.

"CP830 Research Project and Thesis 2". Includes bibliographical references (p. 80-93) Electronic reproduction.[S.l. :s.n.],2003.Electronic data.Mode of access: World Wide Web.System requirements: Adobe Acrobat reader software for PDF files.Access restricted to institutions with a subscription.

Originally presented as the author's Thesis (doctoral)--Technische Universität München. / "FGV-TUM." Includes bibliographical references (p. 147-156).

Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 17, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. Susan Flader and Dr. Jeffrey L. Pasley. Includes bibliographical references.

This thesis presents a statistical analysis of weaving in a managed lane system which is evolving from a High-Occupancy Vehicle (HOV) system to a High-Occupancy Toll system (HOT). Weaving was, assessed along the I-85 corridor in Atlanta, during three different phases in the conversion from HOV to HOT: 1) the existing HOV managed lane system prior to conversion to HOT lanes, 2) after restriping of some weaving zones but prior to conversion of the HOV lanes to HOT lanes and, 3) after the HOT managed lane system opened. Each phase was analyzed to see how weaving behavior into and out of the managed lane system was affected by changes in the system. To accomplish the analysis, video was collected using Georgia Department of Transportation cameras along the corridor. The videos were transferred to an Android Tablet, in which an App developed by the research team was used to record data from the videos. Using the processed weaving data, a comparison of weaving activity during each phase was performed. Data were also analyzed across time of day, speed differentials, and whether the weaves in question were performed legally (within established weaving zones) or illegally (across double-solid striped lane markings). After a comparison of weaving behavior along different variables, a regression tree analysis was completed. The analysis showed that weaving intensity increased as the system was converted from HOV to HOT. However, illegal weaving decreased significantly once the HOT system was in place, perhaps due to stricter enforcement or perhaps due to driver response to illegally entering and leaving tolled lanes. The regression tree analyses indicated that weaving intensity was highly dependent upon whether it was legal or illegal to weave and upon the phase of conversion during which the weave occurred.

No description available.

No description available.

Thesis (M. Env. St.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1992. / Includes bibliographical references (leaves 61-65).

Originally presented as the author's Thesis (doctoral)--Technische Universität München. / "FGV-TUM." Includes bibliographical references (p. 147-156).

Congestion on the freeways of the U.S. has increased multifold over the past few years. A significant portion of this congestion is caused by non-recurring events such as incidents. Diversion has been accepted as a method that can reduce delays during incidents. The process of diversion involves the selection of the alternate routes, which is currently done off-line and is not responsive to each incident case. The volumes on these preselected routes on that particular day are also ignored. The preselected routes, in most cases, serve only to bypass the link on which the incident occurs. Considering the volumes that flow on the freeways, this leads to considerable delays in terms of lost time and productivity. Another important issue that is currently neglected is user compliance. The network generator is used to reduce the delays in selection of these alternate routes. It uses characteristics such as the congestion levels and available capacities in selection of alternate routes in real-time. Also, used in selecting alternate routes are feasibility criteria, that significantly affect the available capacities on the links. These include presence of trip generators (schools, offices, etc.) or safety factors (icy bridges, height restrictions, etc.). The model thus generates a reduced network and a set of alternate routes to divert the traffic upstream of the incident. Disutilities that drivers associate with route-choice, such as the number of left-turns and signals, the relative time spent on the freeway and arterials are attached to each route. The routes with the minimum disutilities are displayed to the user. A user-equilibrium assignment module to predict traffic flows in the future is also incorporated into the framework. As a precursor to the network generator, there is a module which calculates the clearance time for an incident. It uses other characteristics of the incident such as the weather and time of occurrence in order to predict if the delays are significant to initiate diversion. Numerous tests were conducted in order to validate the rules and functions developed. The tests were based on varying incident and traffic conditions. The results showed that the model, was able to select better routes for off-peak conditions rather than peak conditions. There is a threshold value of the delay caused by the incident, beyond which the model is very effective. / Master of Science