As the demand for flexible organic light-emitting diodes (OLEDs) grows beyond that for rigid OLEDs, various elements of OLEDs, such as thin-film transistors, electrodes, thin-film encapsulations (TFEs), and touch screen panels, have been developed to overcome OLEDs’ physical and chemical limitations through material and structural design. In particular, TFEs, which protect OLEDs from the external environment, including reactive gases, heat, sunlight, dust, and particles, have technical difficulties to be solved. This review covers various encapsulation technologies that have been developed with the advent of atomic layer deposition (ALD) technology for highly reliable OLEDs, in which solutions to existing technical difficulties in flexible encapsulations are proposed. However, as the conventional encapsulation technologies did not show technological differentiation because researchers have focused only on improving their barrier performance by increasing their thickness and the number of pairs, OLEDs are inevitably vulnerable to environmental degradation induced by ultraviolet (UV) light, heat, and barrier film corrosion. Therefore, research on multi-functional encapsulation technology customized for display applications has been conducted. Many research groups have created functional TFEs by applying nanolaminates, optical Bragg mirrors, and interfacial engineering between layers. As transparent, wearable, and stretchable OLEDs will be actively commercialized beyond flexible OLEDs in the future, customized encapsulation considering the characteristics of the display will be a key technology that guarantees the reliability of the display and accelerates the realization of advanced displays.

Recently, unmanned aerial vehicles (UAVs) have been used in various fields, such as military, logistics, transportation, construction, and agriculture, making it possible to apply the limited activities of humans to various and wide ranges. In addition, UAVs have been utilized to construct topographic data that are more precise than existing satellite images or cadastral maps. In this study, a monitoring point for preventing flood damage in an urban area was selected using a UAV. In addition, the topographic data were constructed using a UAV, and the flow of rainwater was examined using the watershed analysis in an urban area. An orthomosaic, a digital surface model (DSM), and a three-dimensional (3D) model were constructed for the topographic data, and a precision of 0.051 m based on the root mean square error (RMSE) was achieved through the observation of ground control points (GCPs). On the other hand, for the watershed analysis in the urban area, the point in which the flow of rainwater converged was analyzed by adjusting the thresholds. A monitoring point for preventing flood damage was proposed by examining the topographic characteristics of the target area related to the inflow of rainwater.

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In this study, an estimation method for damage and recovery costs on account of domestic droughts was developed. The estimation method for the scale of damage was applied based on the national drought statistics generated by the Ministry of Public Administration and Security. The damage and recovery costs of domestic droughts were calculated based on the damage data of domestic droughts that occurred in 2018 and 2019. The estimation method was developed for damage costs incurred due to domestic droughts by considering the number of people affected by water supply restrictions, accommodation, and restaurants. The method for estimating recovery costs after domestic droughts was developed considering domestic disaster support, water support, water development support, equipment support, and human resource support for victims. Due to the construction of a DB of limited domestic drought damage status, the damage costs were calculated for the number of people affected by water supply restrictions, and the recovery costs were calculated for the domestic disaster and water support. The total damage costs caused by domestic droughts in 2018 amounted to 612.471 M KRW, and in Gangwon-do and Jeollanam-do, they were 218.616 M KRW in 2019, and more than 90% of Incheon metropolitan city was calculated. The total recovery costs caused by domestic droughts in 2018 were 5,994.555 M KRW, and in Gangwon-do and Jeollanam-do, they amounted to 4,882.024 M KRW in 2019, and more than 90% of Chungcheongnam-do was calculated. The difference between the damage and recovery costs of domestic droughts was approximately tenfold in 2018 and twentyfold in 2019.

: Conventional method to estimate mass of particulate matter accumulated in diesel particulate filter is to use pressure difference between upstream and downstream of the filter. Then measured pressure difference should be compared that of clean condition which is no particulate matter accumulated in DPF. During regeneration soot oxidation is also estimated by same method. This methodology, however, has demerit on accuracy because of pressure difference deviation of clean DPFs and pressure difference caused by non-carbon based PM which is different from that of caused by carbon based PM. This study suggests new methodology to estimate accumulated soot oxidation rate through exhaust gas characteristics during regeneration. Results, more high accuracy of soot oxidation was obtained by analysis of relationship between fuel mass and concentration of carbon dioxide and oxygen.