Junshi Xu

Dr. Junshi Xu

Department of Civil & Mineral Engineering, University of Toronto, Toronto, ON, M5S 1A4, Canada

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2022 in Applied Energy
Verified
Journal Article
Closed access
An WangAn Wang
An Wang
Junshi XuJunshi Xu
Junshi Xu
MZMingqian Zhang
Mingqian Zhang
ZZZhiqiang Zhai
Zhiqiang Zhai
GSGuohua Song
Guohua Song
MHMarianne Hatzopoulou
Marianne Hatzopoulou

1 January 2022 in Science of The Total Environment
Verified
Journal Article
Closed access
RTRan Tu
Ran Tu
Junshi XuJunshi Xu
Junshi Xu
AWAn Wang
An Wang
MZMingqian Zhang
Mingqian Zhang
ZZZhiqiang Zhai
Zhiqiang Zhai
MHMarianne Hatzopoulou
Marianne Hatzopoulou


31 August 2022 in Environmental Science & Technology
Verified
Journal Article
Closed access
Junshi XuJunshi Xu
Junshi Xu
MZMingqian Zhang
Mingqian Zhang
AGArman Ganji
Arman Ganji
KMKeni Mallinen
Keni Mallinen
An WangAn Wang
An Wang
MHMarianne Hatzopoulou
Marianne Hatzopoulou

22 July 2023 in Environment International
Verified
Journal Article
Open access
MLMarshall Lloyd
Marshall Lloyd
AGArman Ganji
Arman Ganji
Junshi XuJunshi Xu
Junshi Xu
AVAlessya Venuta
Alessya Venuta
LSLeora Simon
Leora Simon
SWScott Weichenthal
Scott Weichenthal
Concentrations of outdoor ultrafine particles (UFP; <0.1 µm) and black carbon (BC) can vary greatly within cities and long-term exposures to these pollutants have been associated with a variety of adverse health outcomes. This study integrated multiple approaches to develop new models to estimate within-city spatial variations in annual median (i.e. average) outdoor UFP and BC concentrations as well as mean UFP size in Canada's two largest cities, Montreal and Toronto. We conducted year-long mobile monitoring campaigns in each city that included evenings and weekends. We developed generalized additive models trained on land use parameters and deep Convolutional Neural Network (CNN) models trained on satellite-view images. Using predictions from these models, we developed final combined models. In Toronto, the median observed UFP concentration, UFP size, and BC concentration values were 16,172pt/cm3, 33.7 nm, and 1225 ng/m3, respectively. In Montreal, the median observed UFP concentration, UFP size, and BC concentration values were 14,702pt/cm3, 29.7 nm, and 1060 ng/m3, respectively. For all pollutants in both cities, the proportion of spatial variation explained (i.e., R2) was slightly greater (1-2 percentage points) for the combined models than the generalized additive models and a greater (approximately 10 percentage points) than the deep CNN models. The Toronto combined model R2 values in the test set were 0.73, 0.55, and 0.61 for UFP concentrations, UFP size, and BC concentration, respectively. The Montreal combined model R2 values were 0.60, 0.49, and 0.60 for UFP concentration, UFP size, and BC concentration models respectively. For each pollutant, predictions from the combined, deep CNN, and generalized additive models were highly correlated with each other and differences between models were explored in sensitivity analyses. Predictions from these models are available to support future epidemiological research examining long-term health impacts of outdoor UFPs and BC.

1 October 2020 in Environmental Pollution
Verified
Journal Article
Closed access
Junshi XuJunshi Xu
Junshi Xu
AWAn Wang
An Wang
NSNicole Schmidt
Nicole Schmidt
MAMatthew D Adams
Matthew D Adams
MHMarianne Hatzopoulou
Marianne Hatzopoulou