• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.38-38
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• 2012

The East Asia (EA) region including China, Taiwan, Japan, and Korea are especially vulnerable to hydrometerological extremes during the boreal summer (June-September). This study, therefore, pursued an exploratory analysis to improve better understanding of the potential impacts of the two types of PJ patterns on WNP Tropical cyclone (TC) activities and TC-induced extreme moisture fluxes over Korea's five major river basins. This study shows that during positive PJ years, the large-scale atmospheric environments are more favorable for the TC activities than those in negative PJ years. During positive PJ year, it is found that there are weaker wind shear, stronger rising motion, as well as large relative humidity over the Korean peninsula (KP) compared to negative PJ years. As a result, TCs making landfall are more exhibited over the southeastern portions of South Korea. Despite the relatively modest sample size, we expect that insights and results presented here will be useful for developing a critical support system for the effective reduction and mitigation of TC-caused disasters, as well as for water supply management in coupled human and natural systems.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.12
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• pp.4795-4815
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• 2020

Drone detection can be considered as a specific sort of small object detection, which has always been a challenge because of its small size and few features. For improving the detection rate of drones, we design a Deeper SSD network, which uses large-scale input image and deeper convolutional network to obtain more features that benefit small object classification. At the same time, in order to improve object classification performance, we implemented the up-sampling modules to increase the number of features for the low-level feature map. In addition, in order to improve object location performance, we adopted the down-sampling modules so that the context information can be used by the high-level feature map directly. Our proposed Deeper SSD and its variants are successfully applied to the self-designed drone datasets. Our experiments demonstrate the effectiveness of the Deeper SSD and its variants, which are useful to small drone's detection and recognition. These proposed methods can also detect small and large objects simultaneously.

• Journal of Environmental Health Sciences
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• v.48 no.1
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• pp.9-18
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• 2022

In today's civilization, it can be impossible to prevent disasters that cause large-scale human and material harm, and the environmental industry is not excepted from this. Over the last 50 years, several large and small environmental health catastrophes have occurred in Korea. Notable instances include the phenol pollution accident in the Nakdong River, the Hebei Spirit oil spill in Taean, Chungcheongnam-do, and the humidifier disinfectant disaster. Looking at these instances, it is clear that the government failed to prevent similar incidents and accidents after the tragedies. The government created and executed different policies to prevent such incidents and accidents, but the majority of them were highly fragmented. It is understandable that depending on the political and social level of the society in which the environmental health hazard incident/accident happened, the investigation of the cause, countermeasures, and policy reaction may differ. To put it another way, the more authoritarian and non-democratic a political social system is, the more likely it is to cover up occurrences and accidents without a deep examination. This is in line with the members of society's level of political awareness and acknowledgment of the importance of life and safety. In 1985, when the Onsan pollution disease was discovered, and in 2011, when we recognized the realities of the humidifier disinfectant disaster, South Korea's political and social systems were entirely different.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.41.3-42
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• 2021

Coma cluster (Abell 1656) is one of the most massive local galaxy clusters such as Virgo, Fornax, and Perseus, which holds a large collection of globular clusters. Globular cluster systems (GCSs) in a galaxy cluster tell us a history of hierarchical cluster assembly and intracluster GCs (ICGCs) are known to trace the gravitational potential of the galaxy cluster. Previous studies of GCSs in Coma mainly utilized data obtained using Hubble Space Telescope (HST) with high spatial resolution. However, most of the data were based on narrow-field pointing observations. In this study we present the widest survey of GCSs in the Coma cluster using the archival Subaru/Hyper Suprime-Cam (HSC) g and r images, supplemented with the archival HST images. The Coma GCSs are largely extended in E-W and SW direction, along the general direction of Coma-Abell 1367 filament. This global structure of the GCSs is consistent with the spatial distribution of the intracluster light (ICL). ICGC spatial distribution is largely extended to almost ~50% of the virial radius. Most of these ICGCs are blue and metal-poor, which supports the scenario that ICGCs are mainly originated from dwarf galaxies and some proportion from brighter galaxies. Implications of the results will be discussed.

• Journal of Wellbeing Management and Applied Psychology
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• v.7 no.4
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• pp.15-20
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• 2024

Purpose: Climate change is greatly affecting the frequency and intensity of fires around the world. The main effects of climate change on fires are rising temperatures, dry seasons and extreme droughts, changes in precipitation, increased strong winds, extended fire danger periods, and changes in natural ecosystems. Several factors due to climate change are increasing the risk of large-scale fires, such as wildfires. Research design, data and methodology: Rising temperatures caused by climate change will make forests and grasslands drier, make it easier for wildfires to occur in drier environments and spread quickly to wider areas, and the generated wildfires will release large amounts of greenhouse gases into the atmosphere, such as carbon dioxide (CO₂), and the released greenhouse gases will strengthen the global greenhouse effect, further raising the temperature. As temperatures rise, the risk of wildfires increases in drier environments, and this process is repeated, leading to a vicious cycle of intensifying climate change as more fires occur and more greenhouse gases are released. Results: In conclusion, climate change is increasing the risk of fire occurrence and this phenomenon is expected to become more frequent and severe in the future. Conclusions: In order to cope with the increasing fire risk caused by climate change, fire prevention and management. Fire detection and response systems need to be strengthened, supportive policies and international cooperation are needed to restore ecosystems, and these measures, along with fire prevention, management and countermeasures, should take into account long-term climate change and adaptation as well as short-term responses.

• The Journal of Engineering Geology
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• v.18 no.1
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• pp.17-26
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• 2008

In this study, the design method of slope reinforced by the earth retention systems were systematically developed, and the flow chart of design procedure fur each system were constructed to design the slope rationally. The proposed design method is composed of 5 steps such as field condition investigation step, slope design step, landslide occurrence prediction step, slope failure scale estimation step and reinforcement countermeasure selection step. The quantitative standard of slope failure scale was established based on the arrangement of various overseas standards which is estimating the slope failure, and the analysis of slope failure scale which is occurred in the country. The slope failure scale is classified into three categories the small scale of slope failure is less than $150m^3$ of slope failure volume, the middle scale of slope failure is from $150m^3$ to $900m^3$ and the large scale of slope failure is more than $900m^3$. The earth retention system could be selected by the proposed slope failure scale based on the slope failure volume. Meanwhile, the design methods of earth retention system such as piles, soil nails and anchors were developed. The optimal countermeasure for slope stability could be proposed using above design methods.

• Journal of Families and Better Life
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• v.25 no.5
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• pp.47-63
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• 2007

The purpose of this study was to verify the effectiveness of an internal family systems therapy program aimed at increasing ego-identity of middle-aged women. The objectives of this program were for middle-aged women to differentiate the self of internal systems, to identify constraints impinging on an individual part, to release constraints impinging on an individual part, to harmonize the internal family, and to enhance ego-identity. 31 middle-aged women ranged in age from 40 to 60. Two groups were identified as equivalents for the study in the pre-test. The program of this experimental group was implemented twice a week for 120 minutes per each session over a 6-week period. The pre-test(Aug. 29. 2006), the post-test(Oct. 20. 2006) and the follow-up test(Nov. 20. 2006) were implemented in order to verify the effectiveness of the programs. The participants who were absent more than three times in the program were excluded from the post-test and follow-up test. Eventually, the data in 31 persons(15 for the internal family systems therapy, 16 for the control group) were analyze to verify the effectiveness of the program. The instruments used in the study were the ego-identity scale. The data were analyzed using repeated measures ANOVA, simple main effect, post-hoc t-test, means and standard deviations. And the program was from Sep. 5. to Oct. 20. 2006. The findings of the study were as follows: The internal family systems therapy program had significant effects on enhancing the ego-identity. There was a large increase of the ego-identity in the intervention group, compared with control group at post treatment and follow-up after 1 month which indicated the continuity of intervention effect. However, in the control group, there were no changes according to the time.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.6
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• pp.2230-2250
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• 2015

Multiple projectors with partially overlapping regions can be used to project a seamless image on a large projection surface. With the advent of high-resolution photography, such systems are gaining popularity. Experts set up such projection systems by subjectively identifying the types of errors induced by the system in the projected images and rectifying them by optimizing (correcting) the parameters associated with the system. This requires substantial time and effort, thus making it difficult to set up such systems. Moreover, comparing the performance of different multi-projector display (MPD) systems becomes difficult because of the subjective nature of evaluation. In this work, we present a framework to quantitatively determine the quality of an MPD system and any image projected using such a system. We have divided the quality assessment into geometric and photometric qualities. For geometric quality assessment, we use Feature Similarity Index (FSIM) and distance-based Scale Invariant Feature Transform (SIFT). For photometric quality assessment, we propose to use a measure incorporating Spectral Angle Mapper (SAM), Intensity Magnitude Ratio (IMR) and Perceptual Color Difference (ΔE). We have tested the proposed framework and demonstrated that it provides an acceptable method for both quantitative evaluation of MPD systems and estimation of the perceptual quality of any image projected by them.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.4
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• pp.1562-1578
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• 2020

Vector data compression algorithm can meet requirements of different levels and scales by reducing the data amount of vector graphics, so as to reduce the transmission, processing time and storage overhead of data. In view of the fact that large threshold leading to comparatively large error in Douglas-Peucker vector data compression algorithm, which has difficulty in maintaining the uncertainty of shape features and threshold selection, a segmented Douglas-Peucker algorithm based on node importance is proposed. Firstly, the algorithm uses the vertical chord ratio as the main feature to detect and extract the critical points with large contribution to the shape of the curve, so as to ensure its basic shape. Then, combined with the radial distance constraint, it selects the maximum point as the critical point, and introduces the threshold related to the scale to merge and adjust the critical points, so as to realize local feature extraction between two critical points to meet the requirements in accuracy. Finally, through a large number of different vector data sets, the improved algorithm is analyzed and evaluated from qualitative and quantitative aspects. Experimental results indicate that the improved vector data compression algorithm is better than Douglas-Peucker algorithm in shape retention, compression error, results simplification and time efficiency.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.1
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• pp.49-56
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• 2023

With the development of technology worldwide, bridges are becoming larger, and the number of old bridges is also rapidly increasing. Monitoring the structural health of large, aging bridges is essential to preventing large-scale accidents. In this study, the application of a LoRa low-power wide-area network (LPWAN)-based wireless measurement system was investigated, and a LoRa wireless measurement system was established in the cable-stayed bridge section of Cheonsa Bridge, located in Shinan-gun, Jeollanam-do, Korea. The applicability of the LoRa LPWAN-based wireless monitoring system to large marine bridges was reviewed by comparing the performance and economic feasibility with wire-based monitoring systems that were built and operated by establishing a measurement system for the pylons, cables, and reinforcing girders of the bridge.