{'fraction_non_alphanumeric': 0.012517385257301807, 'fraction_numerical': 0.009735744089012517, 'mean_word_length': 4.665354330708661, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Multidimensional interpretation of the air quality change by the installation of PSD in a subway station

The purpose of this research is to measure the change of the air pollutants in a subway station by the installation of a platform screen door (PSD) system and find the effect of the PSD system on the change of the indoor air quality in a subway station. Principal component analysis (PCA) is used to investigate the installation effect and interpret their multivariate relationships between the indoor pollutants. Data set which was measured at the Y-station during 7 months is used for this study, which consists of 9 variables. The indoor air quality in a platform shows a big difference between existence and nonexistence of PSD. PSD system has a strong effect on the concentrations of PM10 and PM2.5 in a subway station by its blocking effect from re-suspension of the particulate. The PCA analysis confirms that there is a correlation of PM10 and PM 2.5 between indoor and outdoor air and also between before and after the PSD installation. This difference represents that the correlation of the contaminant variables has been changed by the PSD system and the correlation of PM10 and PM2.5 also varied under the PSD. This study shows that a multidimensional analysis can find the cause and result of the indoor air quality variation by the PDS system and effectively interpret the change of the pollutants in a subway station.