The correlation between atmospheric visibility and influenza in Wuxi city, China

Juan Liu; Enpin Chen; Qi Zhang; Ping Shi; Yumeng Gao; Yujun Chen; Wendong Liu; Yiran Qin; Yuan Shen; Chao Shi

doi:10.1097/md.0000000000021469

An Atmospheric Visibility Grading Method Based on Ensemble Learning and Stochastic Weight Average

Atmosphere ◽

10.3390/atmos12070869 ◽

2021 ◽

Vol 12 (7) ◽

pp. 869

Author(s):

Xiuguo Zou ◽

Jiahong Wu ◽

Zhibin Cao ◽

Yan Qian ◽

Shixiu Zhang ◽

...

Keyword(s):

Ensemble Learning ◽

Traffic Accidents ◽

Feature Sets ◽

Atmospheric Visibility ◽

Average Accuracy ◽

Level 3 ◽

Visual Characteristics ◽

Level 1 ◽

Grading Model ◽

Level 2

In order to adequately characterize the visual characteristics of atmospheric visibility and overcome the disadvantages of the traditional atmospheric visibility measurement method with significant dependence on preset reference objects, high cost, and complicated steps, this paper proposed an ensemble learning method for atmospheric visibility grading based on deep neural network and stochastic weight averaging. An experiment was conducted using the scene of an expressway, and three visibility levels were set, i.e., Level 1, Level 2, and Level 3. Firstly, the EfficientNet was transferred to extract the abstract features of the images. Then, training and grading were performed on the feature sets through the SoftMax regression model. Subsequently, the feature sets were ensembled using the method of stochastic weight averaging to obtain the atmospheric visibility grading model. The obtained datasets were input into the grading model and tested. The grading model classified the results into three categories, with the grading accuracy being 95.00%, 89.45%, and 90.91%, respectively, and the average accuracy of 91.79%. The results obtained by the proposed method were compared with those obtained by the existing methods, and the proposed method showed better performance than those of other methods. This method can be used to classify the atmospheric visibility of traffic and reduce the incidence of traffic accidents caused by atmospheric visibility.

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The Effect of Some Gasoline Compositional Factors on Atmospheric Visibility and Soiling

10.4271/720253 ◽

1972 ◽

Cited By ~ 3

Author(s):

John M. Pierrard ◽

Richard A. Crane

Keyword(s):

Atmospheric Visibility

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Contrast Enhancement and Optimization for Image with Fog

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.380-384.3778 ◽

2013 ◽

Vol 380-384 ◽

pp. 3778-3781

Author(s):

Wei Na Huang ◽

Zheng Xiang Xie

Keyword(s):

Contrast Enhancement ◽

Real Time ◽

Visual Quality ◽

Experimental Results ◽

Video Monitoring ◽

Adaptive Model ◽

Absorption Effect ◽

Atmospheric Visibility ◽

Normal Work ◽

Computing Speed

Aiming at the absorption effect of fog suspended in the atmosphere on light, the paper established the removing-fog compensation adaptive model which can improve the atmospheric visibility and restore the normal work of outdoor system. The experimental results show that the removing fog image processed by the method of removing-fog compensation optimization can accord with the requirement of human visual, and it can be used in real-time video monitoring as the fast computing speed. The method not only can be used in foggy video which the fog distributed uniformly, and can assess the visual quality for the images processed.

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Modeling aerosol impacts on atmospheric visibility in Beijing with RAMS-CMAQ

Atmospheric Environment ◽

10.1016/j.atmosenv.2013.02.030 ◽

2013 ◽

Vol 72 ◽

pp. 177-191 ◽

Cited By ~ 41

Author(s):

Xiao Han ◽

Meigen Zhang ◽

Jinhua Tao ◽

Lili Wang ◽

Jian Gao ◽

...

Keyword(s):

Atmospheric Visibility

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An Observational Study on HIV and Syphilis Rates and Associated Risk Factors Among Elderly Men in Wuxi, China

10.21203/rs.3.rs-152414/v1 ◽

2021 ◽

Author(s):

Ying Chen ◽

Yining Bao ◽

Zunyou Wu ◽

Sarah Robbins ◽

Minjie Chu ◽

...

Keyword(s):

Health Knowledge ◽

Eastern China ◽

Case Control ◽

People Living With Hiv ◽

Valuable Insight ◽

Significant Prognostic Factor ◽

Elderly Men ◽

Matched Case ◽

Living With Hiv ◽

Wuxi City

Abstract Background: Human immunodeficiency virus (HIV) remains a nationwide health problem in China, there were a reported 1,045,000 people living with HIV/Acquired Immune Deficiency Syndrome (AIDS) by the end of October 2020, and the number of individuals aged 50 years and older living with HIV has also increased over the past two decades.Methods: A cross-sectional and 1:2 matched case-control studies were conducted from July to August 2016, in three community of Wuxi city, eastern China. A total of 1000 men aged 50 and over completed a face-to-face interview regarding their HIV-related knowledge and attitudes, as well as risk behaviors. All participants also provided a five-milliliter blood sample for syphilis and HIV testing.Results: Among the 1,000 participants, the mean age was 64.7±8.1 years. Less than half of the participants answered all HIV and sexually transmitted diseases (STDs)-related questions correctly (range 40.7%-63.9%). Younger men (χ2=23.175, P<0.05) with more education (χ2=52.054, P<0.05) were more knowledgeable about HIV compared to others. Less than 10% men knew where to get test for HIV, while only 2.1% had ever been tested. Serological testing showed that 20 participants were currently infected with syphilis and one person was tested positive for HIV antibody, however, none of them admitted having risky behaviors related to HIV/STDs. The 1꞉2 matched case-control indicated that only the AIDS-related attitudes were different between two groups (χ2=8.726, P=0.013), the conditional logistic regression analysis indicated that scores of AIDS health knowledge was the only significant prognostic factor for the infection (HR=0.754 (0.569-0.999), P=0.049).Conclusions: The overall HIV/STDs-related knowledge among elderly men in Wuxi, China was low. Further research aimed at identifying how these factors impact their sexual decision making can shed valuable insight into further prevention program in this population.

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River System Connectivity Analysis of Wuxi’s Central Urban Area Based on Graph Theory

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.212-213.543 ◽

2012 ◽

Vol 212-213 ◽

pp. 543-548 ◽

Cited By ~ 1

Author(s):

Liu Yan Wang ◽

You Peng Xu ◽

Ming Jing Yu

Keyword(s):

Graph Theory ◽

Urban Area ◽

Water Environment ◽

River System ◽

Yangtze River Delta ◽

River Network ◽

Structure Stability ◽

Network Graph ◽

Stream Structure ◽

Wuxi City

Wuxi City is located in the hinterland of Taihu Basin and an important city in Yangtze River Delta Region with a prosperous economy. In the process of urban development, the river system pattern changes a lot. It has an impact on water environment, water ecology and other fields. The central urban area of Wuxi City was selected as the study area. Based on the river system of three periods: 1960s, 1980s and 2009, the rivers were classified into three levels according to the width of channels. The length, acreage and stream structure parameters were calculated. Then from the view of Graph Theory, river system was expressed as network graph, and the vertices, edges and degree of vertices were analyzed. The results show that the changes of rivers of different levels and lakes are not completely the same, but still appear a decreasing trend in general. The river network density and water surface ratio become smaller. Also the complexity and structure stability of river network weaken. The conclusions that the river evolution tends to be trunk and single, the stream structure is simplified and the connectivity of rivers and lakes reduces are verified by the analysis based on Graph Theory as well.

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Estimating Atmospheric Visibility Using General-Purpose Cameras

Advances in Visual Computing - Lecture Notes in Computer Science ◽

10.1007/978-3-540-89646-3_35 ◽

2008 ◽

pp. 356-367 ◽

Cited By ~ 15

Author(s):

Ling Xie ◽

Alex Chiu ◽

Shawn Newsam

Keyword(s):

General Purpose ◽

Atmospheric Visibility

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Characteristics of PM2.5 Chemical Compositions and Their Effect on Atmospheric Visibility in Urban Beijing, China during the Heating Season

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15091924 ◽

2018 ◽

Vol 15 (9) ◽

pp. 1924 ◽

Cited By ~ 9

Author(s):

Xing Li ◽

Shanshan Li ◽

Qiulin Xiong ◽

Xingchuan Yang ◽

Mengxi Qi ◽

...

Keyword(s):

Fine Particles ◽

Inorganic Ions ◽

Water Soluble ◽

Motor Vehicles ◽

Urban Site ◽

Chemical Compositions ◽

Heating Season ◽

Atmospheric Visibility ◽

Visibility Impairment ◽

Mass Concentrations

Beijing, which is the capital of China, suffers from severe Fine Particles (PM2.5) pollution during the heating season. In order to take measures to control the PM2.5 pollution and improve the atmospheric environmental quality, daily PM2.5 samples were collected at an urban site from 15 November to 31 December 2016, characteristics of PM2.5 chemical compositions and their effect on atmospheric visibility were analyzed. It was found that the daily average mass concentrations of PM2.5 ranged from 7.64 to 383.00 μg m−3, with an average concentration of 114.17 μg m−3. On average, the Organic Carbon (OC) and Elemental Carbon (EC) contributed 21.39% and 5.21% to PM2.5, respectively. Secondary inorganic ions (SNA: SO42− + NO3− + NH4+) dominated the Water-Soluble Inorganic Ions (WSIIs) and they accounted for 47.09% of PM2.5. The mass concentrations of NH4+, NO3− and SO42− during the highly polluted period were 8.08, 8.88 and 6.85 times greater, respectively, than during the clean period, which contributed most to the serious PM2.5 pollution through the secondary transformation of NO2, SO2 and NH3. During the highly polluted period, NH4NO3 contributed most to the reconstruction extinction coefficient (b′ext), accounting for 35.7%, followed by (NH4)2SO4 (34.44%) and Organic Matter (OM: 15.24%). The acidity of PM2.5 in Beijing was weakly acid. Acidity of PM2.5 and relatively high humidity could aggravate PM2.5 pollution and visibility impairment by promoting the generation of secondary aerosol. Local motor vehicles contributed the most to NO3−, OC, and visibility impairment in urban Beijing. Other sources of pollution in the area surrounding urban Beijing, including coal burning, agricultural sources, and industrial sources in the Hebei, Shandong, and Henan provinces, released large amounts of SO2, NH3, and NO2. These, which were transformed into SO42−, NH4+, and NO3− during the transmission process, respectively, and had a great impact on atmospheric visibility impairment.

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