• Korean Journal of Materials Research
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• v.9 no.3
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• pp.234-239
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• 1999

A Abstract Yttria-stabilized zirconia(YSZ) thin films were synthesized by plasma enhanced chemical vapor deposition process. $Zr[TMHD]_4$ $Y[TMHD]_3$ precursors and oxygen were used with the deposition temperature of $425^{\circ}C$ and rf power ranging 0-100 watt. Effects of the deposition parameters were studied by X-ray diffraction and thickness anal­ysis. YSZ thin films have cubic crystal structure with (200) orientation. From the results of EDX analysis, the converte ed content of TEX>$Y_2O_3$ was determined to be 0-36%, and the film thickness was increased with bubbling temperature which is considered to be due to increasing TEX>$Y_2O_3$ flux. The depth profiles of Zr, Y and 0 appeared relatively $\infty$nstant through film thickness. Columnar grains of $1000~2000\AA$ grew vertical to the substrate surface for the case of Ar carri­er gas. In case of He carrier gas, the grain size was observed to be about $1000~2000\AA$. X-ray diffraction data showed the increase of lattice constant with TEX>$Y_2O_3$ content. It was that the presence of the cracks formed during film deposition, partially released the stress generated by the increase of lattice constant.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.832-838
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• 2021

Recently, reports of marine accidents of small fishing vessels less than 10 tons have been increasing. In this study, the characteristics of the motion response in regular waves were analyzed using computations for these ships. Small vessels less than 10 tons are classified by size and used for marine accident investigations. Therefore, the motion response analysis was performed on three small fishing vessels of different sizes. In the case of the head sea, it was confirmed that as the speed of the vessel increased in the long wavelength region, the motion responses of heave and pitch became large. The motion response of the smallest 3-ton fishing vessel was greater than that of the other sizes of fishing vessels. The maximum value of the roll motion shifted to the long wavelength region as the speed gradually increased in the bow sea, regardless of the size of the ship. In all the three small fishing vessels, it was found that the roll motion was the greatest at 15 knots, the highest speed in both bow and beam seas. When sailing in the head sea and bow sea conditions, lowering the speed is one of the effective approaches to reduce the effects of the vertical and lateral plane motions. The roll motion caused by the beam wave showed a tendency to increase rapidly only at a specific wavelength regardless of the speed and the size of the vessel. It was confirmed that the roll motion was significantly reduced with forward speed in the stern wave compared to the bow wave. As there is a specific region where the maximum value of the hull motion response appears depending on the size and speed of the ship, an operation method that can minimize the effect of this motion should be considered and implemented.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.6
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• pp.1-16
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• 2018

The decline in the construction industry has led to a decrease the profitability of small and medium-sized landscape contractors. To relieve this situation, small and medium-sized landscape contractors have continued to proactively find ways to enter global construction markets. However, many small and medium-sized landscape contractors face risks due to their lack of capacity and insufficient preparations to extend the business abroad. Thus, this study aims to analyze the current condition of the Vietnamese construction market and the related risk factors. It then suggests strategies to improve the small and medium-sized landscape contractors' competitiveness in that market. We investigated the business climate and analyzed risk factors. Finally, we developed expansion strategies and conducted in-depth interviews with six overseas construction professionals. The study results first showed that efforts to improve infrastructure and the increased demand for housing in Vietnam will lead to more opportunities for small and medium-sized landscape contractors entering the Vietnamese construction market. However, changes in the Vietnamese business climate may act as a variable. Second, we found that small and medium-sized landscape contractors' risk factors are mainly related to laws and regulations, government finance, market fluctuations, public administration system, minimum wage increases, financing and bonds, contracting, trees and materials, and design errors. Finally, small and medium-sized landscape contractors are required to consider the following when seeking to enter the Vietnamese construction market: short-term strategy and mid-to-long-term strategy. This study will be used as the basis for small and medium-sized landscape contractors to plan to enter the Vietnamese construction market and to contribute to the expansion of the global construction market in the landscape industry.

• Smart Media Journal
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• v.9 no.4
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• pp.176-186
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• 2020

The size and shape of crops are diverse, and the growing environment is also different. Therefore, when one uses a drone to spray pesticides, the characteristics of each crop must be considered, and flight conditions such as the flight height and forwarding velocity of the drone should be changed. The droplet flow of pesticides is affected by various flight conditions, and a large change occurs in the sprayed area. As a result, an uneven distribution of liquid may be formed at the wake, and the transport efficiency will be decreased as well as there would be a risk of toxic scatter. Therefore, this paper analyzes the degree of distribution of pesticides to the crops through numerical analysis when pesticide is sprayed onto the selected three crops with different characteristics by using agricultural drones with different flight conditions. On the purpose of establishing a guideline for spraying pesticides using a drone in accordance with the characteristics of crops, this paper compares the amount of pesticides distributed in the crops at the wake of nozzle flow using the figure of merit, and the sum of transported liquid rate divided by the root mean square of the probability density function.

• Korean Journal of Psychosomatic Medicine
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• v.30 no.1
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• pp.1-6
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• 2022

Recently, nonsuicidal self-injury (NSSI) has been increasing considerably in school counseling. According to the Youth Counseling and Welfare Development Institute, the number of counseling support for NSSI adolescent in 2018 was more than three times higher than the previous year, and the average time when NSSI behavior first appeared was 12.43 years old. As such, adolesnect NSSI continues to increase in recent years, and the age is also gradually decreasing. Nevertheless, research on the motives and characteristics of NSSI among domestic adolescents is still insufficient. This may be attributed to the difficulty of conducting research because self-injury behavior is secretly performed. However, it is also true that this reality has another limitation in the school field, which urgently requires counseling intervention and prevention of students' mental health problems. In addition, counseling for self-injury in the school scene is the biggest cause of exhaustion for counselors because they are under very great stress to cope with repeated self-harm in the dual role of counselors and teachers in school situations. Therefore, this study examines the causes and characteristics of involuntary self-injury through previous research analysis, and examines various difficulties experienced as a school counselor, as well as the effective intervention method of non suicidal self-injury in school counseling.

• Korean Journal of Psychosomatic Medicine
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• v.30 no.1
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• pp.38-45
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• 2022

Objectives : The purpose of this study is to analyze Mental health literacy in General population. Methods : We analyze the National Mental Health Literacy and Attitude Survey Data in 2021. We investigate 2016 general population and evaluate sociodemographic characteristics, Mental health literacy and stigma. We utilize 4 Case vignette which consist of Major Depressive Disorder, Schizophrenia, Alcohol Use Disorder and Suicidal Ideation. Results : Schizophrenia (27.6%) have the lower disease recognition compare to Major Depressive Disorder (43.8%) and Alcohol Use Disorder (61.7%) (p<0.001). The stigma of Alcohol use disorder (52.8%) is highest and the stigma of Schizophrenia (47.2%) is the second highest (p<0.001). Conclusions : The education and overcoming the stigma in Mental health is needed in Schizophrenia and Alcohol Use Disorder.

• Journal of Korea Water Resources Association
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• v.55 no.4
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• pp.257-266
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• 2022

Inundation damage is increasing every year due to localized heavy rain and an increase of rainfall exceeding the design frequency. Accordingly, the importance of hydraulic structures for flood control and defense is also increasing. The hydraulic structures are designed according to its purpose and performance, and the amount of flood is an important calculation factor. However, in Korea, design rainfall is used as input data for hydrological analysis for the design of hydraulic structures due to the lack of sufficient data and the lack of reliability of observation data. Accurate probability rainfall and its temporal distribution are important factors to estimate the design rainfall. In practice, the regression equation of temporal distribution for the design rainfall is calculated using the cumulative rainfall percentage of Huff's quartile method. In addition, the 6^th order polynomial regression equation which shows high overall accuracy, is uniformly used. In this study, the optimized regression equation of temporal distribution is derived using the variable selection method according to the principle of parsimony in statistical modeling. The derived regression equation of temporal distribution is verified through the significance test. As a result of this study, it is most appropriate to derive the regression equation of temporal distribution using the stepwise selection method, which has the advantages of both forward selection and backward elimination.

• Korean Journal of Psychosomatic Medicine
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• v.31 no.1
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• pp.33-41
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• 2023

Objectives : The purpose of this study was to analyze the factors that influencing mental health literacy. Methods : We obtained data on 2016 general population from the Korean Mental Health Literacy Survey (2021) conducted by Ministry of Health and Welfare. Multiple regression analysis was used to evaluate the associations between sociodemographic characteristics and the score of questionnaire items in Korean Mental Health Literacy Survey. Results : Among the factors, female (p<0.001), higher age (p=0.005), higher income level (p<0.001) were significantly correlated with higher score of questionnaire items. Awareness of mental health center & community addiction management center (p=0.002), awareness of mental health hotline service (p<0.001) were also significantly associated with higher response score. Conclusions : The factors affecting mental health literacy could be considered when providing community mental health services.

• Geophysics and Geophysical Exploration
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• v.11 no.1
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• pp.26-33
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• 2008

The analysis of wide-angle seismic reflection and refraction data plays an important role in lithospheric-scale crustal structure study. However, it is extremely difficult to develop an appropriate velocity structure model directly from the observed data, and we have to improve the structure model step by step, because the crustal structure analysis is an intrinsically non-linear problem. There are several subjective processes in wide-angle crustal structure modelling, such as phase identification and trial-and-error forward modelling. Because these subjective processes in wide-angle data analysis reduce the uniqueness and credibility of the resultant models, it is important to reduce subjectivity in the analysis procedure. From this point of view, we describe two software tools, PASTEUP and MODELING, to be used for developing crustal structure models. PASTEUP is an interactive application that facilitates the plotting of record sections, analysis of wide-angle seismic data, and picking of phases. PASTEUP is equipped with various filters and analysis functions to enhance signal-to-noise ratio and to help phase identification. MODELING is an interactive application for editing velocity models, and ray-tracing. Synthetic traveltimes computed by the MODELING application can be directly compared with the observed waveforms in the PASTEUP application. This reduces subjectivity in crustal structure modelling because traveltime picking, which is one of the most subjective process in the crustal structure analysis, is not required. MODELING can convert an editable layered structure model into two-way traveltimes which can be compared with time-sections of Multi Channel Seismic (MCS) reflection data. Direct comparison between the structure model of wide-angle data with the reflection data will give the model more credibility. In addition, both PASTEUP and MODELING are efficient tools for handling a large dataset. These software tools help us develop more plausible lithospheric-scale structure models using wide-angle seismic data.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.396-400
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• 2007

Various ways of automated guideway transit construction are being planned recently owing to the policies of the national government and local municipalities as well as increasing investment from the private sector. Particularly, the increase in the private investment is increasing greatly in SOC (Social Overhead Cost). This trend of promoting private sector investment must be conducted on the basis of a thorough analysis of the economic feasibility of the project from the government and construction companies in the private sector. In other words, an accurate cost analysis of initial investment cost (Construction cost), maintenance/repair cost, profit making through the operation of the concerned facilities, cost of dissolution, etc. in terms of the life cycle is very much in need. Nevertheless, the analysis of uncertainty factors and its probabilistic theory are in need of development so that they can be used in the analysis of the economic feasibility of a construction project. First of all, the actual studies on maintenance/repair cost of automated guideway transit are scarce as of yet, prohibiting an accurate computation of the cost and its economic analysis. Accordingly, this study focused on the uncertainty analysis of the economic feasibility for civil engineering structures among automated guideway transit construction projects based on the rapidly increasing investment on such structures from the private sector. For this research purpose, a cost classification system for the automated guideway transit is proposed, first of all, and the data On the cost cycle of the civil structure facilities and their unit cost are collected and analyzed. Then, the uncertainty in the cost is analyzed from the perspective of LCC. In consideration of the current status with almost no. studies on maintenance/repair of such facilities, it is expected that the cost classification system and the uncertainty analysis technique proposed in this study will greatly enhance LCC analysis and economic feasibility studies for automated guideway transit projects in the future.