Macdonald Engineering Building

Montréal, Canada

Macdonald Engineering Building

Montréal, Canada
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Walsh A.,Francois Xavier Bagnound Building | Walsh A.,University of Michigan | Forbes J.R.,MacDonald Engineering Building | Forbes J.R.,McGill University | And 4 more authors.
Journal of Guidance, Control, and Dynamics | Year: 2017

Extremum-seeking guidance endeavors to drive the output of a system to the extremum of an unknown objective function. This paper proposes an extremum-seeking guidance algorithm on SO(3) for cases with and without inclusion and exclusion zones. The gradient of the unknown objective function is estimated via a Kalman filter so that the extremum of the objective function can be approximated. To satisfy inclusion and exclusion zone constraints, two different constrained Kalman filters are proposed. The first Kalman filter is a gain-projected Kalman filter, and the second is a novel linear matrix inequality based Kalman filter that is able to accommodate a larger class of constraints. The proposed extremum-seeking guidance algorithm is demonstrated using a performance objective that relates a spacecraft's attitude to received power of an unknown radiation source using a patch antenna. Copyright © 2017 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.


Alam A.,Macdonald Engineering Building | Hatzopoulou M.,Macdonald Engineering Building
Transportation Research Part D: Transport and Environment | Year: 2014

This study investigates the impacts of transit improvement strategies on bus emissions along a busy corridor in Montreal, Canada. The local transit provider, Société de Transport de Montréal, has implemented a number of strategies which include the use of smart cards, limited-stop (express bus) service, and reserved bus lanes along this corridor. Using data collected on-board for instantaneous speeds and stop-level ridership, we estimated bus emissions of greenhouse gases and other pollutants at three levels: road segment, bus-stop, and per passenger. A regression of segment-level emissions against a number of explanatory variables reveals that reserved bus lanes and express bus service reduce emissions significantly. On the other hand, smart card use reduces idling emissions compared to other fare payment methods. Our findings are of most relevance for transit planners who are seeking to implement different strategies to reduce emissions and improve transit performance. © 2014 Elsevier Ltd.


Zahabi S.A.H.,Macdonald Engineering Building | Strauss J.,Macdonald Engineering Building | Manaugh K.,Macdonald Engineering Building | Miranda-Moreno L.F.,Macdonald Engineering Building
Transportation Research Record | Year: 2011

Road facilities in urban areas are a major source of injury for nonmotorized road users despite the benefits of nonmotorized transportation. In particular, large Canadian cities such as Montreal face serious problems with pedestrian and cyclist safety. To address these problems, funds are continually allocated through different safety improvement programs such as reduction of speed limits, improvement of intersections, and increased traffic enforcement. However, few analytical tools help to identify and quantify the benefits of countermeasures (e.g., roadway design, speed management strategies, or land use policies) in reducing accident frequency and severity. Injury severity models were developed to determine the effects of road design, built environment, speed limits, and other factors (e.g., vehicle characteristics and movement type) on injury severity levels of pedestrians and cyclists involved in collisions with motor vehicles. Sources of data included police reports describing vehicle-pedestrian and vehicle-cyclist collisions, as well as information on land use, transit network, and road design attributes from the city of Montreal. The impacts of road design, land use, built environment, and other strategies on the injury severity levels of vulnerable road users were investigated. Factors such as darkness, vehicle movement, whether an accident occurred at an intersection, vehicle type, and land use mix affected the severity of pedestrian injuries from collisions. For cyclists, however, only vehicle movement and whether the accident occurred at a signalized intersection had significant effects on the severity of the injury.


Madani Hosseini M.,McGill University | Shao Y.,Macdonald Engineering Building | Whalen J.K.,McGill University
Biosystems Engineering | Year: 2011

The cement industry produces about 5% of the global anthropogenic carbon dioxide (CO2) emissions. Global demand for cement is forecast to grow by 4.7% annually, which will increase CO2 emissions. One way to mitigate the CO2 generated during cement manufacturing is to use biocement. Biocement is a blend of bio-silica, produced from combustion of organic residues, with Portland cement. Biocement requires less energy intensive clinker, with its related carbon emission, to produce a good cementing agent. Small scale biocement production in tropical areas has shown that blending cement with bio-silica can have environmental, economic and technical benefits. It is also found that a number of crops grown in temperate regions of Canada with high silicon concentration and calorific content have the potential to make biocement. In addition, the combustion process can be integrated into energy production to simultaneously gain the energy and the bio-silica ash. The results indicated that switchgrass, barley, oat and sunflower produce silicon-rich residues and could be good candidates to consider for both energy and biocement production in Canada. © 2011 Elsevier Ltd.


Alam A.,Macdonald Engineering Building | Hatzopoulou M.,Macdonald Engineering Building
Atmospheric Environment | Year: 2014

In this study, we simulated the operations and greenhouse gas (GHG) emissions of transit buses along a busy corridor and quantified the effects of two different fuels (conventional diesel and compressed natural gas) as well as a set of driving conditions on emissions. Results indicate that compressed natural gas (CNG) reduces GHG emissions by 8-12% compared to conventional diesel, this reduction could increase to 16% with high levels of traffic congestion. However, the benefits of switching from conventional diesel to CNG are less apparent when the road network is uncongested. We also investigated the effects of bus operations on emissions by applying several strategies such as transit signal priority (TSP), queue jumper lanes, and relocation of bus stops. Results show that in congested conditions, TSP alone can reduce GHG emissions by 14% and when combined with improved technology; a reduction of 23% is achieved. The reduction benefits are even more apparent when other transit operational improvements are combined with TSP. Finally a sensitivity analysis was performed to investigate the effect of operational improvements on emissions under varying levels of network congestion. We observe that under "extreme congestion", the benefits of TSP decrease. © 2014 Elsevier Ltd.


Erfani R.,Macdonald Engineering Building | Chouinard L.,Macdonald Engineering Building | Cloutier L.,Macdonald Engineering Building
Atmospheric Research | Year: 2014

The objective of the work presented here is to improve estimates of atmospheric icing hazards, specifically for radial ice accumulation on electrical transmission lines, by clustering freezing rainstorms into different groups and using de-aggregate statistical analysis. In this paper, freezing rain storms were clustered based on anomaly maps constructed using NCEP reanalysis data of 1000. hPa to 500. hPa geopotential heights or SLP. The procedure is demonstrated with data from Montreal, as well as a superstation of Montreal, Quebec City, and Ottawa together. The physical meaning of the different clusters was also analyzed and discussed in terms of wind speed, total precipitation or ice accumulation, air mass positions, and compared with Rauber's archetypical patterns. The results presented indicate that the clusters have statistical and physical significance. Clustering based on either SLP or 1000. hPa to 500. hPa height anomalies produces clusters with different precipitation characteristics which can be explained on a physical basis. Clustering Montreal storms based on 1000. hPa to 500. hPa height anomalies produced one cluster containing the five worst ice storms that occurred in Montreal during that time period. This cluster was characterized by an expansive zone of 1000. hPa to 500. hPa height positive anomalies over Montreal that extend far north. It also shows significant SLP anomalies and cold air damming. The de-aggregated hazard analysis is able to demonstrate that the relative contribution of each cluster changes for more extreme events. The de-aggregated analysis produces optimal statistical fits for clusters and introduces robustness in the estimation of the return period over a range threshold. Finally, a small bias is suggested in the single population analysis where the return periods are consistently lower over a range of quantiles and thresholds. © 2014 Elsevier B.V.


Alam A.,Macdonald Engineering Building | Hatzopoulou M.,Macdonald Engineering Building
Transportation Research Part D: Transport and Environment | Year: 2014

This study investigates the isolated and combined effects of network congestion, roadway grade, passenger load, and fuel type on transit bus emissions of greenhouse gases (GHG) through a simulation of transit operations and emissions along a busy corridor. We also test the effect of changing random seed on overall corridor emissions. We observe that positive grades have strong effects on emissions. Grade also causes other variables to become important such as passenger load. While an increasing passenger load on the bus increases emissions, we observe that the addition of each passenger influences the per-passenger emissions differently depending on the bus occupancy. When the bus is less crowded each additional passenger can decrease per-passenger emissions by 5% whereas the reduction becomes 1.2% when the bus is crowded. Finally, we observe that the reduction potential of compressed natural gas (CNG) compared to conventional diesel could reach up to 40% depending on speed, grade, and passenger load. CNG benefits increase with increasing congestion, and decrease with increasing grade and passenger load. The results of this study are most relevant to transit planners in the evaluation of potential operational changes with emission reduction potential and in the allocation of alternative fuelled buses along selected transit corridors. © 2014 Elsevier Ltd.


Barla P.,Laval University | Miranda-Moreno L.F.,Macdonald Engineering Building | Lee-Gosselin M.,Laval University
Transportation Research Part D: Transport and Environment | Year: 2011

The paper examines the determinants of urban travel greenhouse gas emissions. Specifically, we examine the impact of individual and household socio-economic characteristics as well as the effect of land use and transit supply characteristics around the residence and work place. The analysis uses an activity-based longitudinal panel survey in the Quebec City region of Canada. We find that emissions vary considerably depending on the respondent gender, professional status, age, family structure, income level and day of the week. Particularly, we find evidence of significant economies of scale within Quebec City households in the production of greenhouse gas emissions. We also find major differences in emissions depending upon the type of neighbourhood. A respondent living in the city periphery would produce on average 70% more emissions than if he was located at the city center. Land use and transit supply attributes are, however, also extremely different between these two locations. When estimating the elasticity of emissions with respect to land use and transit supply indicators such as residential density, these emerge as relatively small. © 2011 Elsevier Ltd.

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