Characterisation parameter of atmospheric pollutant concentration for external insulation

2020 ◽  
Vol 14 (20) ◽  
pp. 4547-4552
Author(s):  
Bin Cao ◽  
Fanghui Yin ◽  
Daiming Yang ◽  
Liming Wang ◽  
Masoud Farzaneh
2021 ◽  
Vol 237 ◽  
pp. 01037
Author(s):  
Haizhen Zhang ◽  
Jiang Wei

During the epidemic period, Urumqi has been sealed off from the city’s management, just as “suspended” state.From an environmental point of view, the reduction of energy consumption during the closure of the city can be considered as an energy control to study the resulting reduction of atmospheric pollutant concentration changes.In this paper, the monitoring data of air pollutant concentration in the same period of city closure and normal years are compared, and the results show that the air pollutant concentration has decreased in different degrees during the period of city closure.The largest decrease was44.66% for NO2, -40.13% for CO, -36.44% for PM2.5, and the smallest was-2.06% for SO2.Multivariate analysis of variance showed that energy control had a significant effect on the concentration of pollutants during the city closure, for example NO2 (F=128.96, Sig.=0.000), PM10 (F=29.58, Sig=0.000), PM2.5 (F=13.98, Sig.=0.000), CO(F=46.34;Sig.=0.000). Through the analysis of the data, it can be concluded that the air quality of Urumqi in winter is poor and the concentration of pollutants is high. The energy control during the closing period played a positive role in pollutant emission reduction and effectively improved the quality of atmospheric environment.


2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Bingchun Liu ◽  
Xiaoling Guo ◽  
Mingzhao Lai ◽  
Qingshan Wang

Air pollutant concentration forecasting is an effective way which protects health of the public by the warning of the harmful air contaminants. In this study, a hybrid prediction model has been established by using information gain, wavelet decomposition transform technique, and LSTM neural network, and applied to the daily concentration prediction of atmospheric pollutants (PM2.5, PM10, SO2, NO2, O3, and CO) in Beijing. First, the collected raw data are selected by feature selection by information gain, and a set of factors having a strong correlation with the prediction is obtained. Then, the historical time series of the daily air pollutant concentration is decomposed into different frequencies by using a wavelet decomposition transform and recombined into a high-dimensional training data set. Finally, the LSTM prediction model is trained with high-dimensional data sets, and the parameters are adjusted by repeated tests to obtain the optimal prediction model. The data used in this study were derived from six air pollution concentration data in Beijing from 1/1/2014 to 31/12/2016, and the atmospheric pollutant concentration data of Beijing between 1/1/2017 and 31/12/2017 were used to test the predictive ability of the data set test model. The results show that the evaluation index MAPE of the model prediction is 7.45%. Therefore, the hybrid prediction model has a higher value of application for atmospheric pollutant concentration prediction, because this model has higher prediction accuracy and stability for future air pollutant concentration prediction.


1976 ◽  
Vol 33 (9) ◽  
pp. 2089-2096 ◽  
Author(s):  
John G. Stockner ◽  
Naval J. Antia

Examples are cited from the literature of phytoplankton-related pollution and nutrition studies where the possibility of successful adaptation and subsequent growth could have been overlooked because of insufficient duration of algal exposure to the pollutant or nutrient tested. We present evidence from our investigations where: a) initial algal exposures as long as 20–40 days to the pollutant or alternative nutrient may be required for successful adaptation, and b) phytoplankters initially tolerating only a low level of pollutant concentration could be trained to accept severalfold higher levels by repeated exposure to gradually increasing pollutant concentration A plea is made for future investigators to recognize the importance of long-term bioassays ascertaining algal potential for adaptation, in order that their results may be ecologically realistic for the purpose of environmental protection against chronic pollution and eutrophication. The short-term "shock" response should be clearly distinguished from the long-term habituation response of phytoplankters to the test chemical in these bioassays. Possible problems raising questionable objections to the long-term bioassay approach are discussed.


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