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Pritchard D.R.,Metrolinx | Miller E.J.,University of Toronto
Transportation | Year: 2012

Agent-based microsimulation models of transportation, land use or other socioeconomic processes require an initial synthetic population derived from census data, conventionally created using the iterative proportional fitting (IPF) procedure. This paper introduces a novel computational method that allows the synthesis of many more attributes and finer attribute categories than previous approaches, both of which are long-standing limitations discussed in the literature. Additionally, a new approach is used to fit household and person zonal attribute distributions simultaneously. This technique was first adopted to address limitations specific to Canadian census data, but could also be useful in U. S. and other applications. The results of each new method are evaluated empirically in terms of goodness-of-fit. © 2011 Springer Science+Business Media, LLC.

Hamilton B.T.,CH2M | Murphy C.,CIMA | Piliounis R.,Metrolinx
ITA-AITES World Tunnel Congress 2016, WTC 2016 | Year: 2016

The Eglinton-Crosstown Light Rail Transit line is a 19-kilometre corridor with a 10-kilometre underground portion currently being constructed by Metrolinx in Toronto through a densely populated urban environment. Tunneling works are being completed through two separate design-bid-build contracts that include consideration for a phased handover to a follow on contractor who will take ownership of the tunnels, including warranties, and will complete the stations and remainder of the system through a PPP delivery model including maintenance of the system for 30 years. Warranty provisions, settlement apportionment, tunnel leakage, potential delays and conflicts between contractors are just some of the risks the team managing tunnel contract integration had to consider when developing the PPP contract. This paper will present an overview of how these risks were assessed and allocated through the contracts and the strategies adopted to minimize risks to Metrolinx while ensuring successful procurement was maintained.

Engel-Yan J.,Metrolinx | Passmore D.,IBI Group
ITE Journal (Institute of Transportation Engineers) | Year: 2010

Several approaches employed to revise parking requirements are discussed. The most common approach for determining a minimum parking requirement for a particular use is to collect data on the peak daily parking demand for a number of similar sites and set a parking ratio based on the 85th percentile of demand. Another approach is area-specific parking requirements in which the zones within a city would be defined and possibly grouped, with each area having its own particular parking requirements. The next approach is flexible parking requirements providing detailed citywide context sensitivity without developing unique parking standards for each of a city's neighborhoods. Another is form-based approach that incorporates the concept of urban transects, which form a concept of urban transects, which defines the relation of zones to one another and its evolution over time. A form-based approach has the potential to perform well in terms of alignment with long-term planning objectives, predictability, and ease of enforcement.

Mammen G.,University of Toronto | Faulkner G.,University of Toronto | Buliung R.,University of Toronto | Lay J.,Metrolinx
BMC Public Health | Year: 2012

Background: The declining prevalence of Active School Transportation (AST) has been accompanied by a decrease in independent mobility internationally. The objective of this study was to compare family demographics and AST related perceptions of parents who let their children walk unescorted to/from school to those parents who escort (walk and drive) their children to/from school. By comparing these groups, insight was gained into how we may encourage greater AST and independent mobility in youth living in the Greater Toronto and Hamilton Area, Canada. Methods. This study involved a cross-sectional design, using data from a self-reported questionnaire (n =1,016) that examined parental perceptions and attitudes regarding AST. A multinomial logistic regression analysis was used to explore the differences between households where children travelled independently to school or were escorted. Results: Findings revealed that unescorted children were: significantly older, the families spoke predominantly English at home, more likely to live within one kilometer from school, and their parents agreed to a greater extent that they chose to reside in the current neighborhood in order for their child to walk to/from school. The parents of the escorted children worried significantly more about strangers and bullies approaching their child as well as the traffic volume around school. Conclusions: From both a policy and research perspective, this study highlights the value of distinguishing between mode (i.e., walking or driving) and travel independence. For policy, our findings highlight the need for planning decisions about the siting of elementary schools to include considerations of the impact of catchment size on how children get to/from school. Given the importance of age, distance, and safety issues as significant correlates of independent mobility, research and practice should focus on the development and sustainability of non-infrastructure programs that alleviate parental safety concerns. © 2012 Mammen et al.; licensee BioMed Central Ltd.

Kataria S.,Parsons Brinckerhoff | Hassan I.,Metrolinx
North American Tunneling - 2014 Proceedings, NAT 2014 | Year: 2014

Construction projects are typically exposed to socio-political, legal & environmental, operational and market related risks increasing project costs and causing delays. A robust risk management plan provides a project with a systematic process for identifying, assessing, evaluating, managing and documenting risks that could jeopardize the success of the project. This paper presents an application of a bottom-up risk management approach to the Metrolinx Toronto Light Rail Transit Program projects that identifies, quantifies and correlates risk and uncertainty, analyzing the collective impact of project risks using the Monte Carlo simulation technique to determine potential cost outcomes and associated confidence levels.

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