scholarly journals Context aware benchmarking and tuning of a TByte-scale air quality database and web service

2021 ◽  
Author(s):  
Clara Betancourt ◽  
Björn Hagemeier ◽  
Sabine Schröder ◽  
Martin G. Schultz
Keyword(s):  
Air Quality ◽  
Web Service ◽  
Statistical Processing ◽  
Quality Metrics ◽  
Context Aware ◽  
Near Surface ◽  
On Demand ◽  
Air Quality Measurements ◽  
Present Context ◽  
And Performance

AbstractWe present context-aware benchmarking and performance engineering of a mature TByte-scale air quality database system which was created by the Tropospheric Ozone Assessment Report (TOAR) and contains one of the world’s largest collections of near-surface air quality measurements. A special feature of our data service https://join.fz-juelich.de is on-demand processing of several air quality metrics directly from the TOAR database. As a service that is used by more than 350 users of the international air quality research community, our web service must be easily accessible and functionally flexible, while delivering good performance. The current on-demand calculations of air quality metrics outside the database together with the necessary transfer of large volume raw data are identified as the major performance bottleneck. In this study, we therefore explore and benchmark in-database approaches for the statistical processing, which results in performance enhancements of up to 32%.

scholarly journals Air Quality Measurements in Laying Hens Housing

2016 ◽  
Vol 39 (1) ◽  
pp. 91-95 ◽  
Author(s):  
Mirko Prodanov ◽  
Miroslav Radeski ◽  
Vlatko Ilieski
Keyword(s):  
Air Quality ◽  
Relative Humidity ◽  
Environmental Conditions ◽  
Laying Hen ◽  
Multiple Measurement ◽  
Net Returns ◽  
Air Quality Measurements ◽  
Physical Measures ◽  
And Performance ◽  
Quality Measurements

AbstractEnsuring good environmental conditions of the poultry houses can be costly for the farmers, but without it losses due to poor bird health and performance due to poor air quality can be much more detrimental to net returns. The goal of this study was to investigate the variations in air quality in various areas inside the laying hen houses. Ten houses with laying hen conventional battery cages were measured for O2, H2S, CO, NH3, temperature, relative humidity, CO2, airflow and luminance. The results of the physical measures showed that temperatures in the houses were between 15.31–25.6°C, the relative humidity 48.03-81.12%, while the luminance rarely exceeded 8 lux. As for the gasses, the values for NH3 rarely exceeded 8 ppm, although at some measuring points it reached 26 ppm. O2 was generally at 20.9 %, and the levels of CO2 were very low. No presence of H2S and CO was detected. In this study it was concluded that the measurement of the air quality in a house can vary depending of the places this measures are taken. Multiple measurement points are important because they may make the staff aware of the problems connected to low ventilation and culmination of harmful gases. The air quality in different positions in the houses is of great importance not only for the animal welfare, but also for the safety of the staff.

scholarly journals The Outdoor Dust Information Node (ODIN) – development and performance assessment of a low cost ambient dust sensor

2015 ◽  
Vol 8 (7) ◽  
pp. 7511-7533 ◽  
Author(s):  
G. Olivares ◽  
S. Edwards
Keyword(s):  
Air Quality ◽  
Urban Areas ◽  
Low Cost ◽  
Field Tests ◽  
Significant Challenge ◽  
Air Quality Measurements ◽  
Spatial Coverage ◽  
Baseline Response ◽  
And Performance ◽  
Outdoor Dust

Abstract. The large gradients in air quality expected in urban areas present a significant challenge to standard measurement technologies. Small, low-cost devices have been developing rapidly in recent years and have the potential to improve the spatial coverage of traditional air quality measurements. Here we present the first version of the Outdoor Dust Information Node (ODIN) as well as the results of the first real-world measurements. The lab tests indicate that the Sharp dust sensor used in the ODIN presents a stable baseline response only slightly affected by ambient temperature. The field tests indicate that ODIN data can be used to estimate hourly and daily PM2.5 concentrations after appropriate temperature and baseline corrections are applied. The ODIN seems suitable for campaign deployments complementing more traditional measurements.

Provisioning the standard method for ensuring the reliability of indoor air quality measurements in public transportation

2020 ◽  
Vol 19 (1) ◽  
pp. 47-57
Author(s):  
Ho-Hyun Kim ◽  
◽  
Ho-Hyeong Yang ◽  
Jeong-Hun Lee ◽  
Sang-Hyeon Kang ◽  
...  
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Standard Method ◽  
Public Transportation ◽  
Air Quality Measurements ◽  
Quality Measurements

scholarly journals The impact of measures to reduce ambient air PM<sub>10</sub> concentrations originating from road dust, evaluated for a street canyon in Helsinki

2019 ◽  
Vol 19 (17) ◽  
pp. 11199-11212 ◽  
Author(s):  
Ana Stojiljkovic ◽  
Mari Kauhaniemi ◽  
Jaakko Kukkonen ◽  
Kaarle Kupiainen ◽  
Ari Karppinen ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Air Quality ◽  
Street Canyon ◽  
Dust Emission ◽  
Road Dust ◽  
Ambient Air ◽  
Air Quality Measurements ◽  
Emission Models ◽  
The Impact ◽  
Quality Measurements

Abstract. We have numerically evaluated how effective selected potential measures would be for reducing the impact of road dust on ambient air particulate matter (PM10). The selected measures included a reduction of the use of studded tyres on light-duty vehicles and a reduction of the use of salt or sand for traction control. We have evaluated these measures for a street canyon located in central Helsinki for four years (2007–2009 and 2014). Air quality measurements were conducted in the street canyon for two years, 2009 and 2014. Two road dust emission models, NORTRIP (NOn-exhaust Road TRaffic Induced Particle emissions) and FORE (Forecasting Of Road dust Emissions), were applied in combination with the Operational Street Pollution Model (OSPM), a street canyon dispersion model, to compute the street increments of PM10 (i.e. the fraction of PM10 concentration originating from traffic emissions at the street level) within the street canyon. The predicted concentrations were compared with the air quality measurements. Both road dust emission models reproduced the seasonal variability of the PM10 concentrations fairly well but under-predicted the annual mean values. It was found that the largest reductions of concentrations could potentially be achieved by reducing the fraction of vehicles that use studded tyres. For instance, a 30 % decrease in the number of vehicles using studded tyres would result in an average decrease in the non-exhaust street increment of PM10 from 10 % to 22 %, depending on the model used and the year considered. Modelled contributions of traction sand and salt to the annual mean non-exhaust street increment of PM10 ranged from 4 % to 20 % for the traction sand and from 0.1 % to 4 % for the traction salt. The results presented here can be used to support the development of optimal strategies for reducing high springtime particulate matter concentrations originating from road dust.

scholarly journals Water-Enhanced Flux Changes under Dynamic Temperatures in the Vertical Vapor-Phase Diffusive Transport of Volatile Organic Compounds in Near-Surface Soil Environments

2021 ◽  
Vol 13 (12) ◽  
pp. 6570
Author(s):  
Asma Akter Parlin ◽  
Monami Kondo ◽  
Noriaki Watanabe ◽  
Kengo Nakamura ◽  
Mizuki Yamada ◽  
...  
Keyword(s):  
Air Quality ◽  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Vapor Phase ◽  
Inverse Correlation ◽  
Diffusive Transport ◽  
Near Surface ◽  
Voc Emissions ◽  
Transport Behavior ◽  
Volatile Organic

The quantitative understanding of the transport behavior of volatile organic compounds (VOCs) in near-surface soils is highly important in light of the potential impacts of soil VOC emissions on the air quality and climate. Previous studies have suggested that temperature changes affect the transport behavior; however, the effects are not well understood. Indeed, much larger changes in the VOC flux under in situ dynamic temperatures than those expected from the temperature dependence of the diffusion coefficients of VOCs in the air have been suggested but rarely investigated experimentally. Here, we present the results of a set of experiments on the upward vertical vapor-phase diffusive transport of benzene and trichloroethylene (TCE) in sandy soils with water contents ranging from an air-dried value to 10 wt% during sinusoidal temperature variation between 20 and 30 °C. In all experiments, the flux from the soil surface was correlated with the temperature, as expected. However, the changes in flux under wet conditions were unexpectedly large and increased with increasing water content; they were also larger for TCE, the volatility of which depended more strongly on the temperature. Additionally, the larger flux changes were accompanied by a recently discovered water-induced inverse correlation between temperature and flux into the overlying soil. These results demonstrated that the flux changes of VOCs under dynamic temperatures could be increased by volatilization-dissolution interactions of VOCs with water. Future extensive studies on this newly discovered phenomenon would contribute to a better understanding of the impacts of soil VOC emissions on the air quality and climate.

A Computational Analysis of Flow Field in Twin-Track Subway Tunnel to Improve Air Quality

2013 ◽  
Vol 319 ◽  
pp. 599-604
Author(s):  
Makhsuda Juraeva ◽  
Kyung Jin Ryu ◽  
Sang Hyun Jeong ◽  
Dong Joo Song
Keyword(s):  
Air Quality ◽  
Computational Model ◽  
Stokes Equations ◽  
Ventilation System ◽  
Three Dimensional ◽  
Aerodynamic Characteristics ◽  
Navier Stokes ◽  
Subway Tunnel ◽  
Air Supply ◽  
And Performance

A computational model of existing Seoul subway tunnelwas analyzed in this research. The computational model was comprised of one natural ventilationshaft, two mechanical ventilationshafts, one mechanical airsupply, a twin-track tunnel, and a train. Understanding the flow pattern of the train-induced airflow in the tunnel was necessary to improve ventilation performance. The research objective wasto improve the air quality in the tunnel by investigating train-induced airflow in the twin-track subway tunnel numerically. The numerical analysis characterized the aerodynamic behavior and performance of the ventilation system by solving three-dimensional turbulent Reynolds-averaged Navier-Stokes equations. ANSYS CFX software was used for the computations. The ventilation and aerodynamic characteristics in the tunnel were investigated by analyzing the mass flowrateat the exits of the ventilation mechanicalshafts. As the train passed the mechanical ventilation shafts, the amount of discharged-air in the ventilationshafts decreased rapidly. The air at the exits of the ventilation shafts was gradually recovered with time, after the train passed the ventilation shafts. The developed mechanical air-supply for discharging dusty air and supplying clean airwas investigated.The computational results showed that the developed mechanical air-supplycould improve the air quality in the tunnel.

scholarly journals An Overview of Small Unmanned Aerial Vehicles for Air Quality Measurements: Present Applications and Future Prospectives

Sensors ◽  
2016 ◽  
Vol 16 (7) ◽  
pp. 1072 ◽  
Author(s):  
Tommaso Villa ◽  
Felipe Gonzalez ◽  
Branka Miljievic ◽  
Zoran Ristovski ◽  
Lidia Morawska
Keyword(s):  
Air Quality ◽  
Unmanned Aerial Vehicles ◽  
Aerial Vehicles ◽  
Air Quality Measurements ◽  
Quality Measurements
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