Ing traffic pollution. The air high-quality monitoring sensor (AQMS) was installed at the University of Peshawar’s Physics Department Constructing (see Sulfentrazone Inhibitor Figure A1) at 6 m height from the ground surface level. It is described as an urban background site. Sheffield (53 23 N, 1 28 W) is often a geographically diverse city situated in county South Yorkshire, UK, built on numerous hills hence situated at an elevation of 2900 m above sea level. Sheffield covers a total location of 367.9 km2 having a increasing population of 582,506. Sheffield is claimed to become the “greenest city” in England by the regional city council. Sheffield enjoys a temperate climate with July regarded as the hottest month, with an average maximum temperature of 20.eight C. The air pollution inside the city is primarily due to each road transport and industry, and to a lesser extent, fossil fuel-run processes, including power provide and industrial or domestic heating systems (one example is, wood burners). The AQMS is installed at 2.five m height in the elevated ground surface level in the playground of Hunter’s Bar Infants College (see Figure A2), which lies in close proximity to a busy roundabout, and in the intersection of Ecclesall Road, Brocco Bank, Sharrow Vale Road and Junction Road; therefore, targeted traffic is the major supply of pollution. It’s also described as an urban background web site.Atmosphere 2021, 12,15 ofFigure A1. Aligeron Purity Peshawar study site OpenStreetMap contributors.In our case, the AQMSs are commercially low cost sensor nodes AQMesh. They have been deployed at the two web sites in Peshawar and Sheffield. A “black box” post calibration is applied to the information by the manufacturer to eliminate the influence of humidity and temperature around the sensor and to do away with cross sensitivity. The data are aggregated and sampled each 15 min. The data collected from these nodes are transferred to the cloud-based AQMesh database through typical GPRS communication integrated. The information are then accessed via the dedicated API.Atmosphere 2021, 12,16 ofFigure A2. Sheffield study website OpenStreetMap contributors.Appendix B. The WHO Concentration Criteria for Pollutants All information from `WHO Air quality guidelines for particulate matter, ozone, nitrogen dioxide and sulfur dioxide’ [26]. WHO NOTable A1. WHO Nitrogen dioxide recommendations.Nitrogen Dioxide NO2 WHO SOTable A2. WHO sulfur dioxide suggestions.Annual Mean 40 /m1-h Mean 200 /mSulfur Dioxide SO2 WHO PM2.5 and PM24-h Imply 20 /m10-min Mean 500 /mTable A3. WHO particulate matter suggestions.Particulate Matter PM2.five PMAnnual Mean ten /m3 20 /m24-h Mean 25 /m3 50 /mAtmosphere 2021, 12,17 ofWHO OTable A4. WHO Ozone guidelines.Ozone O3 Appendix C. Approximated Derivatives of SE Kernel8-h Mean one hundred /mBy specifying a kernel function, we can acquire analytical forms of Equations (28) and (29) quickly. In this paper, we adopt the broadly employed SE kernel shown in Equation (A1) as an instance. ( x – x )two k SE ( x, x ) = s2 exp – . (A1) f 2l two You will discover two hyperparameters, i.e., the signal variance s f and length-scale l are involved. Equations (A2) and (A3) show the expectation (prediction mean) partial derivative (EPD) and covariance partial derivative (CPD) of s f , f so s =s f=nni =1 j =nnk ojd ji k oj + d y s f s f ji i 0, 0, j=i j=i ,(A2)=cov(f ) si =1 j =yioo s =s fn n d ji k oj k K(X , X )oo – d ji k oi + k oj k – k oj d ji oi s f s f s f oi s f i =1 j =1 ( xo – x j )2 +( x j – xi )two +( xo – xi )two n n 2s f exp(- ), j = i 2l two =2s f – . -2s exp(- ( xo – x j )2 +( xo – xi )2 ), j=i.