• Journal of Korean Society of Steel Construction
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• v.26 no.4
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• pp.323-334
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• 2014

In this paper, experimental program and associated numerical study were carried out to evaluate the fire resistance of unprotected concrete-filled rectangular steel tubular (CFT) columns subjected to the standard fire. The key testing parameters included the length effect, the load ratio, and the sectional dimensions of the CFT columns. Temperature distribution and axial deformation of the CFT column specimens were measured and analyzed. Rather early local buckling of steel tubes was observed in all the specimens. This caused subsequent load transfer from steel tube to concrete, and eventually triggered concrete crushing, or complete loss of the load bearing capacity of the column. This implies that the limit state of local buckling as well as overall flexural buckling should be incorporated in fire design procedure. As expected, the fire resistance time of specimen with higher load ratio consistently lessened. The prediction of fire resistance time of unprotected CFT columns based on the limiting steel temperature in current design codes or the formula proposed by previous studies is slightly conservative compared to the fire test results available. To establish the finite element analysis model that can be used to predict the thermal and structural behaviour of unprotected CFT columns in fire, the fully coupled thermal-stress analysis was also tried by using the commercial code ABAQUS. The numerical results showed a reasonable global correlation with the experimental results.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.4
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• pp.325-338
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• 2016

Properties of aggregation and spatial distribution of fish were examined based on three lines in the South Sea of Korea using three frequencies (18, 38, and 120 kHz) of a scientific echosounder. The vertical distribution of fish was displayed using acoustic biomass namely nautical area scattering coefficient (NASC). As a result, at 120 kHz high NASC showed from water surface to 20 meters in deep while at 18 and 38 kHz very high NASC presented in 70 ~ 90 meters in depth, especially at line 3. Among three lines, the line 2 had lowest NASC. The horizontal distribution of fish using three frequencies together exhibited high NASC between the eastern South Sea and center of South Sea. In especial, NASC ($801{\sim}1,920m^2/n{\cdot}mile^2$) was observed along coastal waters from Busan to Tongyeong, Geoje, and Namhae. In regard with the property of aggregation of fish schools, the volume back-scattering strength ($S_V$) of three lines presented close each other, however, the range of $S_V$ in the line 2 was shortest (-53.5 ~ -43.4 dB). The average distributional depth was deep in the order of L3 ($32.8{\pm}9.0m$), L1 ($45.2{\pm}9.5m$), L2 ($49.7{\pm}5.6m$). The average altitude was high in the order of L3 ($13.4{\pm}10.3m$), L1 ($17.0{\pm}12.6m$), L2 ($56.7{\pm}5.6m$). The average length, thickness, and area were large in the order of L1, L3, and L2. This means that small sized fish schools were distributed near water surface in the line 2 while relatively large and similar sized fish aggregations between line 1 and line 3 appeared however, fish schools at line 3 had lower distributional depth and smaller compared to those at line 1. Acoustic data were visualized for demonstrating the entire circumstances of survey area. Additionally, there was no correlation between acoustic and trawl results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.11
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• pp.3434-3443
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• 2009

This study was done to examine patients' wound care knowledge and concerns prior to discharge from a tertiary hospital. The participants in this descriptive survey were 112 patients having wounds. During interview, a structured self-administered questionnaire was filled out. The participants were 71 males and 41 females. Wound types were surgical incision (52.7%), percutaneous wound (26.8%), pressure ulcer (9.8%) and diabetic foot and arterial ulcers (5.4%). Their wound care knowledge was 52.0% of correct answer and the mean of concerns (range 1-7) was 2.79. There was no significant correlation between their knowledge and concerns of wound care. The factors influence on wound care concerns were fear of wound care, wound pain, length of hospital stays, and perceived health condition. This findings showed that discharge patients with a wound had some incorrect knowledge and various concerns about wound care. They may help to direct patient teaching in discharge plan.

• Journal of the Institute of Convergence Signal Processing
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• v.14 no.4
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• pp.261-269
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• 2013

This paper describes the design and development of VSI (VLBI standard interface) optical adapter for transmitting VLBI(Very long baseline interferometry) observation data with optical signal. VSI cable comprised of 80-line is being used for observed data transmission with maximum length of 5-meter between playbacks (Mark5B, VERA2000) and raw VLBI data buffer (RVDB), RVDB and VLBI correlation subsystem (VCS) in Daejeon correlator. It has a plan to conduct the data processing for 16-stations and introduce the 14 RVDB systems in near future. And data loss frequently occurred because of trouble of VSI cable MDR80 connector. By considering the data loss by connector error of VSI cable, RVDB system extension plan, effective space usage and long distance data transmission(e-VLBI), the VSI optical adapter was proposed and developed for effectively transmitting and receiving VLBI data through optical signal. In order to confirming the performance of developed VSI optical adapter, the experiments for data transmission was conducted between playback and RVDB system, and confirmed that data transmission was clearly done without any data loss.

• Journal of the Korean Geotechnical Society
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• v.20 no.2
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• pp.27-36
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• 2004

The corrosion rate measurement procedure for the permanent ground anchors using polarization resistance measurements and electrochemical impedance spectroscopy is presented in this paper. The polarization resistance measurements were used to determine the correlation between corrosion rate in the steel and soil characteristics. The electrochemical impedance spectroscopy was used to predict the time dependent corrosion reaction and evaluate the different type of coating systems and the effect of cement grouting on the corrosion attack under various conditions. The results indicate that a low pH soil is a good indicator of a corrosive soil. The low pH soil condition (<5) in both clay and sand has a significant effect on the corrosion reaction of steel members in permanent found anchors. In the case of neutral and alkaline conditions beyond pH 6 in clay and sand, no consistent acceleration of corrosion was measured and the corrosion rate was constant regardless of variations of soil pH levels. Laboratory test data for porcelain clay indicate that the change of soil pH level has a small influence on the corrosion reaction in the steel member. The use of cement footing in the bonded length is sufficient to decrease the corrosion rate to a level close to 0.003∼0.01mm/y at the end of the given period. With epoxy and fusion bonded epoxy coating, the steel specimens remained unaffected and retained the original condition. It is suggested that epoxy and fusion bonded epoxy coating can provide effective protection against corrosion for a long time even in aggressive environment.

• Korean Journal of Human Ecology
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• v.2 no.1
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• pp.45-51
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• 1993

The purpose of this study is to provide some information for the proper education on clothing wearing habits so that the education may be performed in the direction of social needs according to the social change and in the direction of the needs and interest of the high school girl students in their adolescence by being conscious of the influence of clothing on the high school girl students. I have used questionaire as an instrument of measurement. The length of the time of survey is from February 11, 1991 to February 28. The subjects are 544 first grade girl students of general high schools in Cheong-Ju, Choong-Ju, and Je-Cheon. The analysis of the data includes frequency, percentage, average person's Correlation Program, t-test, ANOVA, Scheffe's test. The conclusion of this study is as follows: The first, it is shown that (l)students's interest in the design and fashion of clothing is significantly related to the socio-anthropological and socio-psychological factors such and the education level of their fathers, the education level of their mothers, monthly income of their homes, the clothing habits of their home economics teachers, the subjects which they are interested in, their average scholoary achievements, their religious background, and whether they have boy friends or not, etd. (2)students' interest in purchasing of clothing is significantly related to the socio-anthropological and socio-psychological factors such as the education level of their fathers, the education level of their mothers, monthly income of their homes, the clothing habits of their home economics teachers, the subjects which they are interested in, their average scholoary achievements, and whether they have boy friends or not, etc. (3)students' interest in the social-psyclological aspect is significantly related to the socio-anthropological and socio-psychological factors such as their living area, the clothing habits of their home economics teachers, etc. (4)students' interest in the clothing construction is significantly related to only the clothing habits of their home economics teachersl. (5)students' interest in the clothing management is significantly related to the socio-anthropological and socio-psychological factors such as the education level of their parents, the age of their mothers, their religious background, and their sisters. The second, as for the interest of the high school girl students in clothing, it has been shown that those who wear school uniforms tend to have more interest than those who wear free-choice clothes in such areas as shopping, the construction, and management. As for the other two areas, that is, disign and fashion, and the interest in socio-psychological dependence there has been little meaningful difference between the two groups, while the uniform group has shown more interest than the other group. The third, the interest of hish school students in clothing is considered to be most seriously influenced by their socio-psychological dependence out of five areas of interest. It has been shown that the proportion of the content dealing with clothing wearing life in the high school home economics texbooks in relatively small, especially in such areas as socio-psychological dependence, shopping, management, and design and fashion except in construcion.

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.598-606
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• 2015

This study analyzed the characteristics of the disaster occurrence and disaster-prone zones on the 85 forest roads in the Jeollabuk-do area by referring to their forest environment factors. The on-site survey reveal the types of forest road disasters as follows: erosions of cutting slopes 54.1%, erosions of the filling slope 35.3%, collapses of cutting slopes with filling slope 9.4%, and erosions of road surface 1.1%. Disasters most frequently occurred in the vertical location (the hillside) and the horizontal location (the slope), and the forest factors affecting the road disasters were degree of cutting slopes in $31^{\circ}{\sim}40^{\circ}$, degree of filling slopes in $21^{\circ}{\sim}30^{\circ}$, and the soil texture of SiL. The most significant factors on the most frequent occurrence of forest road disasters were forest type of coniferous, slope aspect northeast, forest age of plantation and felling area, and rainfall in 1601~1700. An analysis of the occurrence of the forest road disasters in the Jeollabuk-do area showed a positive correlative relationship with the following factors of the forest environment within a 1% error: degree of cutting slope in $31^{\circ}{\sim}40^{\circ}$, annual accumulation rainfall in 1601~1700. and showed a positive correlative relationship with the following factors of the forest environment within a 5% error: horizontal location of valley, forest type of coniferous, length of slope more than 20 m, forest age of plantation and felling area, soil texture of SiL.

• Korean Journal of Plant Resources
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• v.33 no.6
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• pp.624-637
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• 2020

High-quality and high-phytonutrient watermelon fruits have strong market opportunities besides their health related benefits. Hence, investigating quality and nutritional related traits of watermelon genetic resources could provide important baseline data in breeding for increased lycopene content thereby increasing the marketability of watermelon. To this end, we have examined some fruit morphological traits and lycopene content of 105 genetic resources. Seeds, originally obtained from 22+ countries, were obtained from the National Agrobiodiversity Center, Jeonju, South Korea, grown in an experimental field and harvested at a fully mature stage. The size of pistil scar (SPS), the width of stripes (WS), weight of fruit (WF), length of fruit (LF), width of fruit (WIF), the thickness of pericarp (TP), soluble solids content (SSC), fruit shape in longitudinal section, ground color of skin, the intensity of the green color of skin, fruit shape at the apical part, grooving distribution, conspicuousness of stripes, and main color of the flesh were recorded on the field and inside laboratory and the lycopene was measured using spectrophotometric and HPLC methods. Watermelon fruits have shown a diverse morphological characters. Red and pink fleshed fruits dominated in the entire collections. Fruits with higher thickness of rind were found to exhibit less soluble solid content (SSC). Korean origin fruits were characterized by intermediate SSC while the United States of America (USA), Russia (RUS), Tajikistan (TJK), Turkmenistan (TKM), Taiwan (TWN), and Uruguay (URY) originated fruits had the highest SSC. The lycopene content varied between 41.37 and 182.82 ㎍/g, 2.81 and 163.72 ㎍/g, and 3.54 and 255.47 ㎍/g using HPLC, UV-Vis spectrophotometer, and microplate reader spectrophotometer, respectively. Red- and pink-fleshed fruits had the highest levels of lycopene content compared to the yellow- and orange-fleshed. Lycopene content had a significant positive correlation with SSC, however, no correlations were detected between lycopene and other quantitative fruit morphological characters. Our study demonstrated high diversity exists in fruit morphological traits and lycopene content of the germplasm collections which provide beneficial baseline data for a future breeding program and utilization of watermelon germplasm collections in gene banks for the maintenance and improvement of the current levels of production, marketability, and health-related benefit of watermelon fruits.

• Physical Therapy Korea
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• v.21 no.4
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• pp.23-33
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• 2014

The aim of this study was to evaluate the effects of walking on a treadmill while using dynamic functional electrical stimulation (Dynamic FES) on functional ability and gait in chronic stroke patients. This was a prospective, randomized controlled study. Twelve patients with chronic stroke (>24 months) who were under grade 3 in dorsiflexor strength with manual muscle test were included and randomized into intervention (Dynamic FES) ($n_1$=7) and control (FES) ($n_2$=5). Both the Dynamic FES group and FES group were given a neuromuscular development treatment. The Dynamic FES group has implemented a total of 60 minutes of exercise treatment and gait training with Dynamic FES application. The FES group, with the addition of applying FES while sitting, has also implemented a total of 90 minutes of gait training on treadmill after the exercise treatment. Both two groups accomplished the program, twice a week, for a total of 24 times in a 12-week period. Exercise treatment, gait training on treadmill, and both Dynamic FES and FES were implemented for 30 minutes each. Korean version activities-specific balance confidence scale (K-ABC) was measured to determine self-efficacy in balance function. Timed up and go (TUG) test was performed to evaluate the physical performance. K-ABC, TUG, Berg balance scale (BBS), modified physical performance test (mPPT) and G-walk were evaluated at baseline and at 12 weeks. After 12 weeks, statistically significant differences (p<.05) were apparent in the Dynamic FES group in the changes in K-ABC and BBS. mPPT, TUG, gait speed, stride length and stance phase duration (%) were compared with the FES group. K-ABC had higher correlation to BBS, along with mPPT to TUG. Our results suggest that walking with Dynamic FES in chronic stroke patients may be beneficial for improving their balance confidence, functional ability and gait.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.552-561
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• 2019

In korea, debris-flow disasters are induced by typhoon and localized torrential rainfall annually. These disasters are particularly severe in the Korean national park due to its geomorphological characteristics. This study was conducted to analyze the landslide characteristics and forest environmental factors of landslide areas located in rugged mountain range in the Korean national park (Mt. Seorak, Mt. Jiri, and Mt. Sobaek). Overall, landslides occurred at 474 sites. The average area of the landslide scar among these sites was 1,212 ㎡. The average landslide sediment was 1,389 ㎥, average landslide length was 75 m, and the average width was 12.9 m. The landslides frequently occurred in regions with igneous rock and coniferous forest. In addition, slope gradient degree (31°-40°), slope gradient direction (N), vertical slope (concave), cross slope (concave), altitude (401-800 m), position (middle), stream order (first order), forest type (mixed), parent rock (igneous), and soil depth (<46 cm). The relationship between landslide soil volume and environmental factors showed positive correlation. The variables of vertical slope (complex), altitude (<1,201 m), and soil depth (<46 cm) correlated significantly at 1 % level.