• Journal of the Korean GEO-environmental Society
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• v.19 no.1
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• pp.25-30
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• 2018

Conventional monitoring method is used for evaluation of the reservoir and levee at the highest height sections. In recent years, automated measurement technology has been developed, and the measurement results are transmitted, collected and stored in real time into management office. Despite the development of real time monitoring technology, the measurement results are not used directly or indirectly with facility management at real time. Recently, as wireless sensor network measurement technology has been developed based on internet of things, this study proposed a real - time measurement and evaluation system based on wireless sensor network technology in the reservoir structure. As a result of the seepage analysis for the application, it was confirmed that the volumetric water content changes together with the change of the seepage line inside the embankment body according to the change of the water level of the embankment. In other words, the applicability of the measurement system with the volumetric water ratio set as the sensor node was verified.

• Korean Journal of Remote Sensing
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• v.21 no.4
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• pp.317-327
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• 2005

The flood is the most general and frequently occurs among natural disasters. Generally flood by the rainfall which extends superexcellently for the occurrence but flash flood from severe rain storm gets up an absurd drowsiness at grade hour. This paper aims to 1 hour real-time flash flood and predict possibility at the area where is the possible flood will occur from the rainfall hour mountain after acquiring data in GIS(Geographic Information System) base by GcIUH(Geomorphoclimatic Instantaneous Unit Hydrograph). The flash flood occurrence is set up at 0.5m, 0.7m and 1.0m in standard depth. And this study suggests standard flood alarm which designed by probable flood according to duration time. The research result shows real-time flash flood evaluation has the suitable standard in the basin when comparing with the existing official warning announcement system considering topographical information.

• Journal of the Korea Convergence Society
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• v.10 no.7
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• pp.343-354
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• 2019

The purpose of this study is to examine the perception of PBL hybrid curriculum of nursing students, using qualitative research conducted through focus group interviews. The data were collected from interviews with 25 nursing students of 4th grade after dividing into 4 groups. The analysis resulted in 6 major categories such as 1) inefficiency of PBL hybrid curriculum, 2) anxiety about learning, 3) dissatisfaction with PBL operation, 4) difficulty in group activity, 5) acceptance of PBL and 6) change and satisfaction. Based on the result, it is suggested that measures should be taken to minimize loss of learning contents in PBL, proportion of course evaluation should be increased to follow original intention of PBL evaluation, and detailed tutor education program should be developed and operated by PBL specialist and professional department.

• Journal of Hydrogen and New Energy
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• v.29 no.6
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• pp.587-595
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• 2018

Recently, research is being conducted to use a fuel cell as a power source of unmanned aircraft. However, safety standards about applying fuel cells to unmanned aircraft are insufficient. In this paper, to improve the safety of the fuel cells for unmanned aircraft is experimentally studied. For this reason, standards for safety of fuel cells were analyzed. And influence of vibration among the evaluation items related to the safety of the fuel cell for unmanned aircraft was discussed. In order to, at constant intervals, vibration was applied to the fuel cell, then the performance was measured, the measurement items were gas tightness, polarization curve, frequency response analysis (FRA). A total of 220 hours was experimented at 20 hour intervals. the result of vibration test, gas leakage rate was a maximum of -0.04826 kPa/min and Polarization curve reached a maximum of 1.0103 times of the initial value, the charge transfer resistance reached a maximum of 1.0104 times of the initial value. This research indicate that performance of fuel cell is affected by vibration and this study is expected to contribute to the safety of fuel cell for unmanned aircraft.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.845-849
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• 2024

Currently, rail surface defects are increasing due to the aging of urban railway rails, but in the detailed guidelines for track performance evaluation established by the country, rail surface damage is inspected with the naked eye of an engineer and with simple measuring tools. It is very important to discover defects in the rail surface through periodic track tours and visual inspection. However, evaluating the severity of defects on the rail surface based on the subjective judgment of the inspector has significant limitations in predicting damage inside the rail. In this study, the characteristics of cracks inside the rail due to rail surface damage were studied. In field measurements, rail surface damage was selected, old rail samples were collected in the acceleration and braking sections, and a scanning electron microscope (SEM) was used to evaluate the rail surface damage was used to analyze the crack characteristics. As a result of the analysis, the crack mechanism caused by the running train and the crack characteristics of the acceleration section where cracks occur at an angle rising toward the rail surface were experimentally proven.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.9
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• pp.775-782
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• 2016

In this study, elevated temperature design and integrity evaluation have been conducted using two different piping design codes for the high-temperature piping systems of sodium integral effect test loop for safety simulation and assessment(STELLA-2) being developed by KAERI(Korea Atomic Energy Research Institute). The design code of ASME B31.1 for power piping and French nuclear grade piping design guideline, RCC-MRx RD-3600 were applied, and conservatism of those codes was quantified based on the piping integrity evaluation results. The piping system of Model DHRS, Model IHTS and PSLS are to be installed in STELLA-2. The integrity evaluation results for the three piping systems according to the two design codes showed that integrity of the piping system was confirmed. As a code comparison result, ASME B31.1 was shown to be more conservative for sustained loads while RD-3600 was more conservative for thermal loads compared to B31.1.

• Mass Spectrometry Letters
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• v.15 no.2
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• pp.79 -94
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• 2024

Over the past few decades, new psychoactive substances (NPS) have become prevailing. With the widespread emergence of NPS, phenethylamines (PEAs) have become one of the groups abused most which PEAs, along with other stimulants, make up the majority of stimulants. When determining the NPS, the methods for screening and confirmation are crucial which assesses the reliability of testimony. In this study, a set of GC/MS methods employing two derivatizing agents for determining 76 target PEAs in urine was established and further applied for authentic sample analysis. Five PEAs (N,N-DMA, PMMA, 4-CA, amphetamine, and methamphetamine) with contents over their LLOQs were detected in thirteen of the twenty tested samples. In order to compare the result from the GC/MS methods with the previously established LC-MS/MS method, Cohen's kappa coefficient and McNemar's test were applied for statistical analysis. Perfect agreement between GC/MS and LC-MS/MS techniques for determining target PEAs is demonstrated by the Kappa coefficient for each of the five detected targets.

• Fashion & Textile Research Journal
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• v.20 no.5
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• pp.592-599
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• 2018

The purpose of this study is to investigate consumer needs, image sensibility and preference of bedding fabric according to size and spacing of dot pattern. 18 kinds of dot pattern fabrics were designed with different diameters(6, 8, 10cm) and distances(4, 7, 10cm) in regular arrangement of diamond figure. The subjects were 162 male and female university students. The data were analyzed by SPSS 24.0. Fabrics were assessed subjectively using a 5-point scale 17 consumer needs and 33 sensory descriptors. The most consumer's needs for bedding fabric was shown to be functionality of bedding including hygiene, touch, warmth, ease of washing and management, air permeability, and hygroscopicity. The other parameters of consumer's needs were shown to be physical property and design parameter. The results of analysis of the dimension of image sensibility for fabrics with different size and spacing of dots are derived from six factors including joyfulness, coziness, uniqueness, charm, femininity, and complexity. As a result of analysis of preference with fabric kinds, there was a significant difference in preference with fabrics. The preferred fabrics were characterized by the pattern and the base fabric being striking three-dimensionally with 1/3 twill and 3/1 twill fabric. Sensory descriptors related to joyful image and unique image were analyzed as evaluation terms that can distinguish the preferences of fabrics. Correlation analysis showed the fabrics are preferred as the difference in luminance and reflectance between the base and pattern of the fabric become larger and the spacing of patterns become closer.

• Journal of the Korean Society of Costume
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• v.58 no.6
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• pp.96-109
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• 2008

The proposes of this study were to exam the effects of internalization of sociocultural values toward appearance on adolescents' body image and clothing behaviors, and to analyze these effects by adolescents' sex and age variables. The research method was survey and the subjects were 447 male and female adolescents in Daejeon, Korea. The questionnaire consisted of 4 measuring instruments; internalization of sociocultural values toward appearance, body image, clothing behaviors, and demographic attributions. The data were analyzed by factor analysis, t-test, variance analysis, Duncan's multiple range test, using SPSS program. The results are as follows. First, most of adolescents showed positive attitude on sociocultural values toward appearance, and female and high school students revealed higher level of internalization than male and middle school students. Second, as a result of factor analysis, 3 factors emerged in body image(appearance interest, appearance evaluation, and weight concern) and 4 factors emerged in clothing behaviors(clothing interest & psychological dependency, clothing ostentation, clothing conformity, and clothing comfort). Third, internalization of sociocultural values toward appearance had important effects on adolescents' body image and clothing behaviors; the adolescents who had high level internalization showed more interest on their appearance and weight and higher clothing interest & psychological dependency and clothing ostentation and lower clothing comfort than other adolescents who had middle or low level internalization. Forth, internalization of sociocultural values toward appearance showed many different effects on body image and clothing behaviors by adolescents' sex and age variables.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.9_10 s.146
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• pp.1219-1229
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• 2005

The objectives of this study were to investigate the differences in clothing and body attitude according to demographic variables, and to examine how clothing and body attitude were influenced by social values and demographic variable of adolescents. The questions of 5-point Likert scale were used for the evaluation of clothing attitude, body attitude, and social values. Four dimensions of social values were derived by factor analysis: 'the sense of estrangement', 'the satisfaction with school life', 'materialism', and' the sense of community'. Subjects were 373 adolescent girls in Seoul(182 middle school students and 191 high school students). The data were analyzed by using factor analysis, t-test, one-way ANOVA, and multiple regression analysis. First, the conformity to entertainers' dresses was influenced by materialism and age(-). Clothing aesthetics was influenced by materialism and allowance, and fashion was influenced by materialism. Second, the interest of plastic surgery was influenced by materialism and allowance. The interest of weight was influenced by the sense of estrangement, school grade(-), the education level of mother, materialism, and the satisfaction with school life. The interest of makeup was influenced by allowance, school grade(-), and the education level of mother(-). Appearance satisfaction was influenced by the sense of estrangement(-) and the satisfaction with school life. The present result means that social values such as materialism and the sense of estrangement are significant variables to understand the appearance attitude of adolescents.