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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.
181

Labour Market Model of the Greater Toronto and Hamilton Area for Integration within the Integrated Land Use, Transportation, Environment Modelling System

Hain, Michael David Lawrence 01 January 2011 (has links)
The Integrated Land Use, Transportation, Environment (ILUTE) modelling system simulates the activities of agents within the Greater Toronto and Hamilton Area (GTHA) as they evolve over time. However, in its currently implemented form, ILUTE lacks an endogenous treatment of the labour market and the associated wages. This is seen as the major weakness of the current model. This work describes a labour market framework to partially fill this gap and then develops the dynamic disaggregate model of year to year transitions of the labour force status of the people within the GTHA and the set of wage models components of this framework. The data used is a sample of individuals from the Toronto, Oshawa, and Hamilton Census Metropolitan Areas surveyed over twelve consecutive years between 1995 and 2007 in the Survey of Labour and Income Dynamics.
182

Labour Market Model of the Greater Toronto and Hamilton Area for Integration within the Integrated Land Use, Transportation, Environment Modelling System

Hain, Michael David Lawrence 01 January 2011 (has links)
The Integrated Land Use, Transportation, Environment (ILUTE) modelling system simulates the activities of agents within the Greater Toronto and Hamilton Area (GTHA) as they evolve over time. However, in its currently implemented form, ILUTE lacks an endogenous treatment of the labour market and the associated wages. This is seen as the major weakness of the current model. This work describes a labour market framework to partially fill this gap and then develops the dynamic disaggregate model of year to year transitions of the labour force status of the people within the GTHA and the set of wage models components of this framework. The data used is a sample of individuals from the Toronto, Oshawa, and Hamilton Census Metropolitan Areas surveyed over twelve consecutive years between 1995 and 2007 in the Survey of Labour and Income Dynamics.
183

Behaviour of Normal and High Strength Concrete Confined with Fibre Reinforced Polymers (FRP)

Cui, Ciyan 23 September 2009 (has links)
An extensive amount of research has been reported in previous literature on the behaviour of FRP-confined concrete subjected to concentric axial compression. However, data on the behaviour of high strength concrete confined with various types and configurations of FRP systems is still lacking and no consensus exists on the complete response of FRP-confined concrete. In addition, no appropriate design guidelines are currently available. This thesis reports results from an experimental program involving 112 cylindrical concrete specimens, 88 of which were FRP-wrapped and the remaining 24 were control specimens. All the specimens were 152 mm in diameter and 305 mm in length. Test variables included: amount of FRP materials used, strength and stiffness of FRP materials, concrete strength, and the health of concrete at the time of strengthening. Experimental results indicated that a pre-repair load of up to 77% of the unconfined concrete strength had no appreciable effect on the stress-strain response of FRP-confined concrete. With an increase of the unconfined concrete strength, the strength enhancement, energy absorption capacity, ductility factor and work (energy) index at rupture of FRP jackets all decreased remarkably. A positive correlation was found between confined concrete ductility and FRP rupture strain. In addition, a gradual post-peak failure of the specimens, observed previously from FRP-confined concrete columns tested at the University of Toronto, was also observed in some of the current tests -- owing to the high speed data acquisition system. That ductile failure can be attributed to the gradual unzipping failure of FRP jacket, which in turn is related to specimen size. A new constitutive model was developed based on material properties, force equilibrium and strain compatibility. The size effect was taken into account in the model, which is able to accommodate concrete with a wide range of strength (25 MPa to 110 MPa) confined with various types and configurations FRP systems. Design equations from CSA S806-02 and CSA S6-06 provide reasonable and conservative estimates for the FRP-confined concrete strength. To calculate the peak strain for FRP-confined concrete, an equation based on the work by Berthet et al. (2006) is proposed.
184

Planning, Design and Scheduling of Flex-route Transit Service

Alshalalfah, Baha Waheed Yousef 13 April 2010 (has links)
The rapid expansion of low-density suburban areas in North America has led to new travel patterns that require transit services to be more flexible. Flex-Route transit service, which combines fixed-route transit service with elements of demand-responsive transit service, has emerged as a viable transit option to address the travel needs of the residents of these areas. Existing literature in this field, however, is limited and lacks any comprehensive analysis of Flex-Route planning, design and scheduling. This research aims at exploring Flex-Route transit service to provide detailed guidelines for the planning and design of the service, as well as developing a new scheduling system for this type of unique service. Accordingly, the objectives of this research are: assessing the practicality of Flex-Route transit service in serving low-density suburban areas; identifying essential Flex-Route planning steps and design parameters; determining the feasibility and cost of replacing fixed-route transit with Flex-Route service; and developing a Flex-Route-specific dynamic scheduling system that relies on recent developments in computer and communication technologies. In this regard, we develop an analytical model that addresses several design parameters and provide a detailed analysis that includes, among other parameters, finding optimal values for Flex-Route service area and slack time. Furthermore, the analytical model includes a feasibility and cost analysis that estimates the cost incurred by several stakeholders if Flex-Route service is chosen to replace fixed-route service. The core of the scheduling system is a new developed algorithm – the Constrained-Insertion Algorithm- that exploits the powerful search techniques of Constraint Programming. The scheduling system can handle the daily operations of Flex-Route transit services; it accepts daily (or dynamic) inputs and, in minimal time, produces very cost-effective and reliable schedules. Moreover, the scheduling system has the ability to be used as simulation tool to allow transit operators to assess the feasibility and performance of proposed Flex-Route transit services before implementation. The applicability of the analytical model as well as the performance of the scheduling system were subsequently evaluated and validated through process that included testing on a case study in the City of Oakville, Canada.
185

Trip Reporting and GPS-based Prompted Recall: Survey Design and Preliminary Analysis of Results

Dumont, Josee 15 January 2010 (has links)
This trip reporting and GPS-based prompted-recall travel survey was undertaken to provide a better understanding of (a) demographic and behavioural differences between students with a home telephone land line and students without one (b) effects of carrying a GPS device on trip reporting (c) differences in trips reported and confirmed through a prompted-recall survey, and (d) performance of the TRIPS platform. The survey was designed and conducted at the University of Toronto between November 2008 and April 2009. It targeted mostly university students and returned 90 valid interviews. Participants were required to carry a GPS device with them for the two days surveyed. They were then asked to report their trips first, and then to confirm their recorded trips through the web-based prompted-recall tool, TRIPS. Preliminary analysis was conducted based on the reported data, and improvements to the TRIPS platform have been suggested.
186

Validation of Road Safety Surrogate Measures as a Predictor of Crash Frequency Rates on a Large-scale Microsimulation Network

Ariza, Alexander 01 December 2011 (has links)
A study was done to explore the suitability of intersection and arterial collision prediction models based on traffic conflicts, generated using the Paramics microsimulation suite and the Surrogate Safety Assessment Model (SSAM). A linear regression model and a generalized linear model with a negative binomial error structure were explored to correlate conflicts to crash rates, as well as the conflict-based models suggested by SSAM. The model predictions were compared to volume-based predictions and historical data from Toronto, Ontario, Canada. The volume- based predictions were calculated using a negative binomial generalized linear model, fitted to the same arterial and intersection sets used to fit the conflict-based models. The results show the predictions generated by a conflict-based model were comparable for intersections, but poor for arterials.
187

An Ex Post Evaluation of the Ridership Impacts of the VIVA Bus Transit System

Forsey, Robert David 07 December 2011 (has links)
The Regional Municipality of York introduced a new bus service known as VIVA in 2005. Although it has been deemed a success by many, it remains to be seen to what degree transit use was affected by its introduction. This study shows that transit ridership in York jumped substantially immediately after the implementation of VIVA. Furthermore, it is determined that the majority of new transit users in York are making home-based work or post-secondary school trips. To evaluate this, home-based work and post-secondary school generalized extreme value discrete choice models are estimated. Improvements in transit service are found to have a greater impact on transit mode share than increases in congestion for both work and post-secondary school trips. It is also, however, concluded that transit improvements played a relatively small role in the considerable shift to transit amongst post-secondary students.
188

Freight on Transit Delphi Study

Cochrane, Keith 21 November 2012 (has links)
The Freight on Transit Delphi Study was conducted to explore the concept of freight on transit – using public transit vehicles and infrastructure for transporting things other than people. Three rounds of web based surveys were conducted with a panel of 34 transportation experts to explore the main issues related to freight and transit integration and to build and evaluate potential freight on transit operations. Survey results were consistent with previous investigations and suggest that organizational disputes are a larger barrier to implementation than technical challenges. Traditional Delphi questions were used to determine the most important positive impacts, negative impacts, and challenges of moving freight on transit networks while survey responses combined with scenario building techniques were used to build and evaluate five potential freight on transit operating strategies using public transit networks in the GTHA.
189

Fibre Reinforcement for Shrinkage Crack Control in Prestressed, Precast Segmental Bridges

Susetyo, Jimmy 23 February 2010 (has links)
In prestressed precast segmental concrete bridges, conventional longitudinal reinforcement serves only as shrinkage crack controllers. The presence of this reinforcement, however, has restricted the ability to reduce the cross-section of the segments when high strength concrete is used because of the minimum dimensions required to accomodate the reinforcement. Research on fibre reinforced concrete (FRC) indicated that the addition of steel fibres to concrete significantly improved the tensile behaviour and the crack control characteristics of the concrete. This research investigates the feasibility of fibres to replace the conventional shrinkage reinforcement, allowing for the design of thinner and lighter structures with comparable or better crack control characteristics. Extensive work was conducted to investigate the effectiveness of hooked-end steel fibres to control cracks. Seven types of material tests were performed: uniaxial tension test, cylinder compression test, modulus of rupture test, splitting test, free and autogenous shrinkage test, and restrained shrinkage test. In addition, ten 890×890×70 mm concrete panels were tested under in-plane pure-shear loading using the Panel Element Tester. The parameters of study were the fibre volume content (0.5%, 1.0%, and 1.5%), the concrete compressive strength (50 and 80 MPa), and the fibre geometry and tensile strength. In addition to the experimental study, a model was developed to investigate the behaviour of a 1D restrained FRC member subjected to shrinkage. The experimental results indicated that the addition of fibres significantly improved the behaviour of the concrete, particularly the crack control characteristics, the post-peak compressive response, the post-cracking tensile response, the toughness, and the ductility of the concrete. The results also indicated that steel fibres were as effective as conventional reinforcement in controlling shrinkage cracking, provided that sufficient fibre volume content was added to the concrete. For example, in order to achieve a maximum crack width of 0.35 mm, a minimum fibre content of 0.9% and 1.1% should be provided for 50 MPa FRC containing high aspect ratio fibres and low aspect ratio fibres, respectively. In addition, the results indicated the importance of fibre content and fibre aspect ratio on the effectiveness of fibre reinforcement.
190

Dynamic Tensile, Flexural and Fracture Tests of Anisotropic Barre Granite

Dai, Feng Jr. 14 February 2011 (has links)
Granitic rocks usually exhibit strongly anisotropy due to pre-existing microcracks induced by long-term geological loadings. The understanding of anisotropy in mechanical properties of rocks is critical to a variety of rock engineering applications. In this thesis, the anisotropy of tension-related failure parameters involving tensile strength, flexural strength and Mode-I fracture toughness/fracture energy of Barre granite is investigated under a wide range of loading rates. Three sets of dynamic experimental methodologies have been developed using the modified split Hopkinson pressure bar system; Brazilian test to determine the tensile strength; semi-circular bend method to determine the flexural strength; and notched semi-circular bend method to determine the Mode-I fracture toughness and fracture energy. For all three tests, a simple quasi-static data analysis is employed to deduce the mechanical properties; the methodology is assessed critically against the isotropic Laurentian granite. It is shown that if dynamic force balance is achieved in SHPB, it is reasonable to use quasi-static formulas. The dynamic force balance is obtained by the pulse shaper technique. To study the anisotropy of these properties, rock blocks are cored and labeled using the three principal directions of Barre granite to form six sample groups. For samples in the same orientation group, the measured strengths/toughness shows clear loading rate dependence. More importantly, a loading rate dependence of the strengths/toughness anisotropy of Barre granite has been first observed: the anisotropy diminishes with the increase of loading rate. The reason for the strengths/toughness anisotropy can be understood with reference to the preferentially oriented microcracks sets; and the rate dependence of this anisotropy is qualitatively explained with the microcracks interaction. Two models abstracted from microscopic photographs are constructed to interpret the rate dependence of the fracture toughness anisotropy in terms of the crack/microcracks interaction. The experimentally observed rate dependence of the anisotropy is successfully reproduced.

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