To protect the population from respiratory diseases and to prevent the damages due to air pollution, the main cause of air pollution should be identified. This research assessed the relationship between the airborne particulate concentrations (PM₁₀) and the urban expansion in Daegu City in South Korea from 2007 to 2017 using multi-temporal spatial datasets (Landsat images, measured PM₁₀ data) and the machine learning technique in the following steps. First, the expanded urban areas were detected from the multiple Landsat images using support vector machine (SVM), a widely used machine learning technique. Next, the annual PM₁₀ concentrations were calculated using the long-term measured PM₁₀ data. Finally, the degrees of increase of the expanded urban areas and of the PM₁₀ concentrations in Daegu from 2007 to 2017 were calculated by counting the pixels representing the expanded urban areas and computing variation of the annual PM₁₀ concentrations, respectively. The experiment results showed that there is a minimal or even no relationship at all between the urban expansion and the PM₁₀ concentrations because the urban areas expanded by 55.27 km² but the annual PM₁₀ concentrations decreased by 17.37 μg/m³ in Daegu from 2007 to 2017.

Choung, Y.-J. and Kim, J.-M., 2019. Relationship between the in-situ-measured sea surface temperatures and the landsat-derived brightness temperatures: A case study in the West Coast of South Korea. In: Lee, J.L.; Yoon, J.-S.; Cho, W.C.; Muin, M., and Lee, J. (eds.), The 3rd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 91, pp. 336-340. Coconut Creek (Florida), ISSN 0749-0208.Assessment of the relationship between the sea surface temperature (SST) and the brightness temperature (BT) is necessary for estimating the SST using the BT data derived from the earth observation satellite sensors. This research assessed the relationship between the in-situ-measured SST data and the BT data derived from the Landsat-8 thermal infrared sensors through the linear regression analysis. The statistical results derived from the developed regression model show the following: the SST and BT datasets have a strong and positive relationship, and the BT data is the significant parameter for measuring the SST. In the future research, the various regression models will be compared to select the most appropriate model for estimating the SST using the BT data.

This paper shows the results of a field appliance study of the hydraulic well method to prevent embankment piping, which is proposed by the Japanese Matsuyama River National Highway Office. The large-scale embankment experiment and seepage analysis were conducted to examine the hydraulic well. The experimental procedure is focused on the pore water pressure. The water levels of the hydraulic well were compared with pore water pressure data, which were used to look over the seepage variations. Two different types of large-scale experiments were conducted according to the installation points of hydraulic wells. The seepage velocity results by the experiment were almost similar to those of the analyses. Further, the pore water pressure oriented from the water level variations in the hydraulic well showed similar patterns between the experiment and numerical analysis; however, deeper from the surface, the larger pore water pressure of the numerical analysis was calculated compared to the experimental values. In addition, the piping effect according to the water level and location of the hydraulic well was quantitatively examined for an embankment having a piping guide part. As a result of applying the hydraulic well to the point where piping occurred, the hydraulic well with a 1.0 m water level reduced the seepage velocity by up to 86%. This is because the difference in the water level between the riverside and the protected side is reduced, and it resulted in reducing the seepage pressure. As a result of the theoretical and numerical hydraulic gradient analysis according to the change in the water level of the hydraulic well, the hydraulic gradient decreased linearly according to the water level of the hydraulic well. From the results according to the location of the hydraulic well, installation of it at the point where piping occurred was found to be the most effective. A hydraulic well is a good device for preventing the piping of an embankment if it is installed at the piping point and the proper water level of the hydraulic well is applied.