Five-year roadside measurements of ultrafine particles in a major Canadian city

Ultrafine Particles and PM2.5 at Three Urban Air Monitoring Stations in Northern Taiwan from 2011 to 2013

“…In the past, numerous studies used the Fast Mobility Particle Sizer (FMPS) (Westerdahl et al, 2009;Sabaliauskas et al, 2012;Betha et al, 2014;Kim et al, 2015) or the Scanning Mobility Particle Sizer (SMPS) coupled with the condensation particle counter (CPC) (Chen et al, 2010a;Breitner et al, 2011;Jayaratne et al, 2011;Wang et al, 2011;Xu et al, 2011;Gao et al, 2012;Young et al, 2012;Cheung et al, 2013;Young et al, 2013;Cheng et al, 2014) to investigate the number concentrations of UFPs. Most of the researches have shown that both local rush hour traffic emission and new particle formation (NPF) play key roles in the diurnal variation of UFPs concentrations, in which two concentration peaks in the morning and evening could be attributed to traffic emission, while one peak in the afternoon is due to NPF (Young et al, 2012;Cheung et al, 2013;Young et al, 2013;Betha et al, 2014;Nikolova et al, 2014).…”

Prediction of ultrafine particle number concentrations in urban environments by means of Gaussian process regression based on measurements of oxides of nitrogen

“…None of the mentioned works uses regulated pollutants as covariates to predict UFP number concentrations. Sabaliauskas et al (2012) predict UFP number concentrations in the 8-50nm (PN 50 ) and 50-100nm (PN 50−100 ) size ranges using NOx and meteorological data in a multiple linear regression model, based on a roadside five years long measurement campaign. Their model explains 52% (R 2 =0.52) of the variance in the case of PN 50 and 63% (R 2 =0.63) in the case of PN 50−100 .…”

“…• As opposed to the previous works (Mølgaard et al, 2012;Clifford et al, 2011;Hussein et al, 2006;Sabaliauskas et al, 2012), we have used simultaneous measurements of NO, NO 2 , CO and O 3 (covariates of the model) and UFP number concentrations (target variable) at three different locations, obtaining a similar model performance at all three locations.…”

“…These data are usually available from the governmental monitoring stations in urban environments. Unlike the study of Sabaliauskas et al (2012), we have measured UFP number concentrations and NOx at the same location.…”

A comparison of strategies for estimation of ultrafine particle number concentrations in urban air pollution monitoring networks

“…Statistical models do not describe the actual physical processes, but they treat the input data as random variables to derive a statistical description of the target distribution using a set of measurements. A few studies have used a statistical approach in the past (Hussein et al 2006;Clifford et al, 2011;Mølgaard et al, 2012;Sabaliauskas et al 2012;Reggente et al, 2014).…”