• Journal of the Korean earth science society
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• v.24 no.4
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• pp.337-345
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• 2003

Surficial sediments from the northern coastal area of Jeju Island, southeastern Yellow Sea (South Sea of Korea) were analyzed for grain-size texture, some geochemical characteristics and clay mineralogy in order to assess their provenance. Rare-earth element compositions and some geochemical discrimination diagrams, especially of Ti/Al, Nb/Al and Rb/Al ratios, were revealed to be useful indices for identifying the origin of sediments. These indices, together with clay mineral compositions, suggest that the coarse-grained sediments originate from the volcanic rocks of Jeju Island, whereas the fine-grained sediments are derived from Chinese rivers, especially the Changjiang River. The oceanic circulation pattern and the physical-chemical properties of seawater in the Yellow and East China seal support the possibility that the fine-pained Changjiang (Yangtze River) sediments can reach the coastal area of Jeju Island (southeastern Yellow Sea).

• Korean Journal of Community Nutrition
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• v.13 no.2
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• pp.288-297
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• 2008

It has been reported frequently that clinical features of gallstone disease in Korean were similarly changing to those of Occidentals. This changing was thought to be due to Westernized lifestyle and dietary patterns in Korean. The purpose of this study was to investigate the nutritional risk factor among patients with gallstone. The subjects of this study were 90 gallstone group with biliary stone as confirmed by cholecystectomy and 111 control group with no biliary stone as confirmed by ultrasonography adjusted according to age and gender. Anthropometric indices and biomarkers were measured and dietary habit as well as nutrient consumption pattern were investigated using a structured checklist of health-related eating behavior and a semi-quantitative food frequency questionnaire. The mean age was higher in GG (gallbladder stone patient group) than CG (control group). The average BMI and WHR (waisthip ratio) tended to be higher than those in CG. WC (waist circumference) and WHR of women in GG were significantly higher than in CG. GG had lower levels in TC (p < 0.01), LDL-C (p < 0.05), and HDL-C (p < 0.05), but higher FBG levels (p < 0.001). GG tended to be associated with lower physical activity and more frequent consumption of meat, meats with high fat and high sugar content food. The consumption levels of fiber (p < 0.05), vitamin C (p < 0.05), calcium (p < 0.01) in GG were significantly lower than in CG. These findings showed that the association with incidence of gallbladder stone and anthrophometric indices and dietary consumption patterns. Further study may be necessary to elucidate the dietary risk factors in the changing patterns of gallstone disease.

• Journal of Navigation and Port Research
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• v.45 no.3
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• pp.165-172
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• 2021

Breaking wave is one of the important design factors in the design of coastal and port structures as they are directly related to various physical phenomena occurring on the coast, such as onshore currents, sediment transport, shock wave pressure, and energy dissipation. Due to the inherent complexity of the breaking wave, many empirical formulas have been proposed to predict breaker indices such as wave breaking height and breaking depth using hydraulic models. However, the existing empirical equations for breaker indices mainly were proposed via statistical analysis of experimental data under the assumption of a specific equation. In this study, a new Munk-type empirical equation was proposed to predict the height of breaking waves based on a representative linear supervised machine learning technique with high predictive performance in various research fields related to regression or classification challenges. Although the newly proposed breaker height formula was a simple polynomial equation, its predictive performance was comparable to that of the currently available empirical formula.

• Nutrition Research and Practice
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• v.14 no.6
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• pp.606-620
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• 2020

BACKGROUND/OBJECTIVES: Although some juices affect subjective sleep quality, there is a lack of information on the effect of a specific juice on objective sleep quality and heart rate variability (HRV) during sleep; thus the present study investigated whether a blended juice made from natural extracts influenced sleep quality and HRV during sleep in adults with disturbed sleep. SUBJECTS/METHODS: A randomized, crossover study was conducted on twenty-five adults (15/10, female/male) complaining of difficulty initiating or maintaining nighttime sleep (Pittsburgh sleep quality index [PSQI] ≥ 5). During feeding sessions (FS), subjects received sleep-inducing juice made of natural ingredients (250 mL/trial) twice a day for 8 weeks or non-FS (N-FS) for 8 weeks while maintaining normal activities. Sleep quality and parameters were recorded via wearable actigraph for 7 consecutive days, and PSQI scores were assessed before and after the intervention. HRV was also monitored at rest and during sleep. RESULTS: After receiving the sleep-inducing juice intervention (FS), PSQI scores were significantly decreased (P < 0.001) and correlated with a significant decline in fatigue severity scale and visual analogue scale levels (P < 0.05; both). HRV indices of vagal activity were significantly improved during FS (P < 0.05), and no significant differences in N-FS were observed. Sleep efficiency and total sleep time increased significantly (P < 0.05) and sleep latency, total counts, sleep fragmentation index, and movement index, decreased significantly (P < 0.05, all 4) during FS, with no significant differences-observed during N-FS. CONCLUSIONS: This study results demonstrated that an 8-week course of sleep-inducing juice has led to improve sleep quality, suggesting an enhanced cardiac vagal tone during sleep. Thus, it could be a well-tolerated option for adults with disturbed sleep.

• Physical Therapy Korea
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• v.23 no.1
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• pp.46-54
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• 2016

Background: Rasch analysis estimates the probability that a respondent will endorse an item and select a particular rating for that item. It has the advantage of placing both the items and the person along a single ration scale and calibrates person ability and item difficulty onto an interval scale by logits. In addition, Rasch analysis is a useful tool for exploring the validity of questionnaires that have been developed using traditional methods. Therefore, it has been recommended as a method for developing and evaluating functional outcome measures. Objects: The purpose of this study was to investigate the item fit, item difficulty, and rating scale of the Korean version of the Fullerton Advanced Balance Scale (KFAB) using Rasch analysis. Methods: Total 97 subjects (39 males and 58 females) with dwelling elderly adults were participated, but 3 people were excluded for misfit persons. Rasch analysis was then done by means of the Winsteps program to determine the item fit, item difficulty, rating scale, and reliability of the KFAB. Results: In this study, the 'standing with feet together and eyes closed', 'two-footed jump', 'walk with head turns', and 'stand on foam, eyes closed' items shown misfit statistics. The most difficult item was 'stand on one leg', whereas the easiest item was 'turn in full circle'. The rating scale was acceptable with all criteria. Both item and person separation indices and reliability showed acceptable values. This would indicated that each domain covers a useful range of item difficulty that is appropriate for measuring a person with a wide range of functional ability. Conclusion: The KFAB has been proven reliable, valid and an appropriate tool with which to evaluate the balance of the elderly people.

• Polymer(Korea)
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• v.27 no.5
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• pp.502-507
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• 2003

The thermal and physical properties of low density polyethylene melt-blended with Metallocene linear low density polyethylenes were investigated. Since the Metallocene polyethylenes have similar MW and MWD except m-LLDPE4, it can be said that the thermal behavior and mechanical properties of the blends depend upon the l-octene comonomer content. The melting behavior of LDPE/m-LLDPE1 blends shows two melting peaks with LDPE contents higher than 50%, while the other blends show only one melting peak. It was observed that the blends show higher crystallization temperature and higher crystallinity with lower comonomer content. Initial modulus of a blend exhibited the behavior proportional to the crystallinity and the elongation at break of the blends was increased with increasing the m-LLDPE composition. Melt indices of the blends decreased with increasing the comonomer content of Metallocene LLDPE. Melt Index values of the blends show negative deviation.

• The Journal of the Korea Contents Association
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• v.11 no.11
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• pp.79-90
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• 2011

The purpose of this study is to explore physical factor of digital text structure for designing e-Book interface and to develop prototype of e-Book interface by applied these factors. To address this goal, explore factor analysis and confirmatory factor analysis were employed, 237 university students were the participated in this study. According to a result, 29 items for physical feature of digital text structure were developed, 9 factors of digital text structure were also extracted; volume, depth, density, space, layout, format, signal, size, and length. Besides, to identify structure of pre-defined 9 factors, confirmatory factor analysis was conducted. As a result of CFA, the factor structure was supported by all of model fit indices.

• Journal of Digital Convergence
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• v.14 no.4
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• pp.479-486
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• 2016

The purpose of this study was to investigate effects of 12-week physical activity intervention on obesity and metabolic syndrome risk factors and smartphone game time in children. A total of 27 children(fifth grade elementary school students) participated in this study. The subjects were divided to exercise group(n=16) and control group(n=11), and participants in exercise group performed running and jump rope(60min/day; 3days/week; 50~70% of THR) during 12-week. We analyzed measurement data using two-way ANOVA. As results, obesity indices except body weight and metabolic syndrome risk factor decreased significantly in exercise group compare with control group. And VO2max increased and smartphone game time decreased significantly in exercise group compare with control group. In conclusion, we suggest that 12-week exercise intervention in children has positive effects on obesity and metabolic syndrome and improve negative lifestyle such as smartphone game.

• Physical Therapy Korea
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• v.24 no.1
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• pp.41-50
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• 2017

Background: The Pediatric Balance Scale (PBS) was developed to assess of balance ability in children with balance problem. The PBS was translated into Korean and its reliability had been studied. However, it had need to be verified using psychometric characteristics including item fit and rating scale. Objects: The purpose of this study was to investigate the item fit, item difficulty, and rating scale of the Korean version of PBS using Rasch analysis. Methods: In total, 40 children with cerebral palsy (CP) (boy=17, girl=23) who were diagnosed with level 1 or 2 according to the Gross Motor Function Classification System participated in this study. The PBS was performed, and was verified regarding the item fit, item difficulty, rating scale, and separation index and reliability using Rasch analysis. Results: In this study, the 'transfer', and 'turning to look behind left and right shoulders while standing still' item showed misfit statistics. in total 40 children with CP. Also, 'transfer', 'standing unsupported with feet together' and 'standing with one foot in front' items showed misfit statistics in diplegia CP group. Regardless of the classification of CP, the most difficult item was 'standing on one foot', whereas the easiest item was 'sitting with back unsupported and feet supported on the floor'. The 4 rating scale categories of PBS were acceptable with all criteria. Both item and person separation indices and reliability showed acceptable values. Conclusion: The PBS has been proven reliable, valid and is an appropriate tool, but it needs to modify the items of PBS according to CP classification.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.99-107
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• 1985

This study was carried out to investigate the nutritional and physical status of children, aged 11 and 12 years, living in Haenam Koon (living at home) and in Mokpo City (living in an orphan asylum) located in Chonnam during the period of August 2 nd to 9 th in 1984. The mean values of height, chestgirth, arm circumference and head circumference between both groups of living in the rural area and in the city orphan asylum were not statistically different and similar to Korean Growth Standard. Exceptionally, the values of height and weight of male living at home in the rural area were lower than Korean Growth Standard (p<0.01). The weight of male living in the city orphan asylum was higher han that of male living at home in the rural area (p<0.01), and the skin fold thickness of female living at home was higher than that of male living at home (p <0.01). The physical indices of children living in the city orphan asylum were more or less higher than those of living at home in the rural area, but the relative weight of male was only significant (p<0.05). The animal protein intake was $8.4{\sim}8.6%$ of total food intake of living at home in the rural area and 6.2% in living in the city orphan asylum. The intake of legumes of children living in the city orphan asylum was more two times than that of living at home in the rural area, but overall fruit intake of living at home was more about two times than that of living in the city orphan asylum. The average intake of all nutrients except thiamine and niacin was lower than RDA. Especially the calcium intake of children in both groups was the lowest of all nutrients ($28.9{\sim}40.6%$ of RDA). Children living at home in the rural area had significantly higher intake of fat and ascorbic acid than children living in the city orphan asylum (p<0.01).