6,874 research outputs found

    Using User Generated Online Photos to Estimate and Monitor Air Pollution in Major Cities

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    With the rapid development of economy in China over the past decade, air pollution has become an increasingly serious problem in major cities and caused grave public health concerns in China. Recently, a number of studies have dealt with air quality and air pollution. Among them, some attempt to predict and monitor the air quality from different sources of information, ranging from deployed physical sensors to social media. These methods are either too expensive or unreliable, prompting us to search for a novel and effective way to sense the air quality. In this study, we propose to employ the state of the art in computer vision techniques to analyze photos that can be easily acquired from online social media. Next, we establish the correlation between the haze level computed directly from photos with the official PM 2.5 record of the taken city at the taken time. Our experiments based on both synthetic and real photos have shown the promise of this image-based approach to estimating and monitoring air pollution.Comment: ICIMCS '1

    Uncovering local aggregated air quality index with smartphone captured images leveraging efficient deep convolutional neural network

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    The prevalence and mobility of smartphones make these a widely used tool for environmental health research. However, their potential for determining aggregated air quality index (AQI) based on PM2.5 concentration in specific locations remains largely unexplored in the existing literature. In this paper, we thoroughly examine the challenges associated with predicting location-specific PM2.5 concentration using images taken with smartphone cameras. The focus of our study is on Dhaka, the capital of Bangladesh, due to its significant air pollution levels and the large population exposed to it. Our research involves the development of a Deep Convolutional Neural Network (DCNN), which we train using over a thousand outdoor images taken and annotated. These photos are captured at various locations in Dhaka, and their labels are based on PM2.5 concentration data obtained from the local US consulate, calculated using the NowCast algorithm. Through supervised learning, our model establishes a correlation index during training, enhancing its ability to function as a Picture-based Predictor of PM2.5 Concentration (PPPC). This enables the algorithm to calculate an equivalent daily averaged AQI index from a smartphone image. Unlike, popular overly parameterized models, our model shows resource efficiency since it uses fewer parameters. Furthermore, test results indicate that our model outperforms popular models like ViT and INN, as well as popular CNN-based models such as VGG19, ResNet50, and MobileNetV2, in predicting location-specific PM2.5 concentration. Our dataset is the first publicly available collection that includes atmospheric images and corresponding PM2.5 measurements from Dhaka. Our code and dataset will be made public when publishing the paper.Comment: 18 pages, 7 figures, submitted to Nature Scientific Report

    Geographically Referenced Data for Social Science

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    An estimated 80% of all information has a spatial reference. Information about households as well as environmental data can be linked to precise locations in the real world. This offers benefits for combining different datasets via the spatial location and, furthermore, spatial indicators such as distance and accessibility can be included in analyses and models. HSpatial patterns of real-world social phenomena can be identified and described and possible interrelationships between datasets can be studied. Michael F. GOODCHILD, a Professor of Geography at the University of California, Santa Barbara and principal investigator at the Center for Spatially Integrated Social Science (CSISS), summarizes the growing significance of space, spatiality, location, and place in social science research as follows: "(...) for many social scientists, location is just another attribute in a table and not a very important one at that. After all, the processes that lead to social deprivation, crime, or family dysfunction are more or less the same everywhere, and, in the minds of social scientists, many other variables, such as education, unemployment, or age, are far more interesting as explanatory factors of social phenomena than geographic location. Geographers have been almost alone among social scientists in their concern for space; to economists, sociologists, political scientists, demographers, and anthropologists, space has been a minor issue and one that these disciplines have often been happy to leave to geographers. But that situation is changing, and many social scientists have begun to talk about a "spatial turn," a new interest in location, and a new "spatial social science" that crosses the traditional boundaries between disciplines. Interest is rising in GIS (Geographic Information Systems) and in what GIS makes possible: mapping, spatial analysis, and spatial modelling. At the same time, new tools are becoming available that give GIS users access to some of the big ideas of social science."

    Environmental Effects of Coronavirus Pandemic: Analysis and Prediction of Global Air Pollution Levels

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    The Covid-19 pandemic started last semester when I was starting on my proposal. At that time, the pandemic lockdowns were at their peak levels with strict restrictions against movements. This was the case in most countries across the world. The effect this had on the air pollution was immediately felt. There were negligible amount of flights and road traffic had also significantly reduced. This led to an amazing clearing of the skies of pollution. For the first time in years, the Himalayan mountains could be seen, and many cities saw their smog and blanket of air pollution disappear. At that point I decided to use the change in air pollution data as the basis for my research. Now in the second semester, lockdowns have been almost lifted all across the world and pollution has re-emerged to pre pandemic lockdown levels. In this research I look at the data for two major gulf cities, Abu Dhabi and Dhahran, Saudi Arabia and investigate the change in pollution data over the past years. The end goal was to estimate whether or not there has been a significant decrease in air pollution levels in both cities over time due to the implementation of lockdowns, which severely restricted industrial production, vehicular pollution, and other forms of man-made emissions. The data collected was then cleaned and variables that were unnecessary were removed. Then I applied Regression analysis onto the data and the results showed evidence of the fact that initiating lockdowns decreased overall pollution levels in the atmosphere, as human activity was severely restricted
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