• Journal of the Society of Naval Architects of Korea
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• v.32 no.3
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• pp.98-106
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• 1995

In ship and offshore structures, there exist many local structural systems which may be regarded as a combined structural systems composed of thick plates or double wall panels and attachments reducible to damped spring-mass systems. For vibration analysis of such a combined system an analytical method based on the receptance method is presented in this paper. The free vibrational characteristics and forced vibration responses of the combined system can be calculated by synthesis of receptances of the panel and attachments. To calculate receptances of the panel, it may be regarded as a Mindlin plate for consideration of effects of shear deformation and rotary inertia and the assumed mode-Lagrange's equation method is applied using Timoshenko beam function or polynomials having properties of Timoshenko beam function as trial functions. Through some numerical calculations, accuracy and efficiency of the presented method are shown.

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.239-246
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• 2010

Aphids are one of the major pests in agricultural crops. A number of synthetic pesticides have been used for control of aphids in agriculture, but increasing public concerns over their adverse effects on the environment have required more environmentally-friendly methods for pest management. In this study, we examined plant oil formulations for the control of green peach aphid (Myzus persicae). Oil formulations were prepared by hydrolyzing the plant oils in ethanolic KOH solution and diluted at the rate of 1:500 for aphid control. The oil formulations showed aphid mortalities ranging from 24.44 to 43.33% in vitro. Significantly increased aphid mortalities were observed by the treatment of oil formulations combined with low-dosed imidacloprid. No significant difference in the aphid mortality was observed between the oil formulations. Mass spectrometry analyses of aphids treated with the low dosedimidacloprid plus the plant oil formulations detected similar concentrations of imidacloprid between the treatments. In field trial bioassays against aphids, significantly decreased aphid population were observed in the pepper plants treated with soybean oil formulation combined with the low-dosed imidacloprid, while aphid population dramatically increased in the pepper plants treated with the low-dosed imidacloprid alone. These results suggested that the plant oil formulations can be used as an environmentally-friendly method for enhancing the insecticidal effectiveness, which may play a role in reducing the use of synthetic pesticide in agriculture.

• Journal of the Korean Geotechnical Society
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• v.30 no.9
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• pp.67-75
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• 2014

Methane gas hydrate which is considered energy source for the next generation has an urgent need to develop reliable numerical simulator for coupled THM phenomena in the porous media, to minimize problems arising during the production and optimize production procedures. International collaborations to improve previous numerical codes are in progress, but they still have mismatch in the predicted value and unstable convergence. In this paper, FEM code for fully coupled THM phenomena is developed to analyze methane hydrate dissociation in the porous media. Coupled partial differential equations are derived from four mass balance equations (methane hydrate, soil, water, and hydrate gas), energy balance equation, and force equilibrium equation. Five main variables (displacement, gas saturation, fluid pressure, temperature, and hydrate saturation) are chosen to give higher numerical convergence through trial combinations of variables, and they can analyze the whole region of a phase change in hydrate bearing porous media. The kinetic model is used to predict dissociation of methane hydrate. Developed THM FEM code is applied to the comparative study on a Masuda's laboratory experiment for the hydrate production, and verified for the stability and convergence.

• Korean Journal of Community Nutrition
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• v.10 no.2
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• pp.183-188
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• 2005

The aim of this study was to assess the effect of 6-week vegetable juice supplementation (360 ml/day) on serum lipid profiles and antioxidant activity in college women. Twenty women (mean age: 21) with normal life style and dietary pattern and who are free of any specific diseases were recruited among the student in S women's university. The subjects consumed vegetable juice to take part in an uncontrolled clinical trial for a 6-week intervention period. While there was no difference in the concentration of total cholesterol and HDL-cholesterol, serum concentrations of TG and HDL/LDL ratio were significantly reduced by $22\%$ (p = 0.013) and $6\%$ (p =0.007) respectively. Significant decrease in manlondialdehyde (p = 0.000) was accompanied by an increase in the activity of serum antioxidant enzymes, such as GSHPx (p = 0.000), SOD (p=0.007). It was also found that total antioxidant status was improved by $5.4\%$ (p=0.009). Serum parameters were all changed without affecting body mass index, waist and hip circumferences, or nutrient intakes after six week of supplementation. This study demonstrated that the supplementation regular meals with vegetable juice can favorably affect serum lipid profiles and antioxidant systems, and hence could contribute to reduce the risks of chronic diseases in college women.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.11
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• pp.1770-1778
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• 2020

Objective: This study was conducted to reveal potential metabolic differences of dairy cows fed corn stover (CS) and rice straw (RS) instead of alfalfa hay (AH) as main forage source. Methods: Thirty multiparous mid-late lactation Holstein dairy cows were selected and randomly assigned to three diets, AH, CS, or RS (n = 10). After 13 weeks of the feeding trial, coccygeal arterial and superficial epigastric venous plasma samples were collected before morning feeding for gas chromatography time-of-flight/mass spectrometry analyses. Results: In the artery, 8 and 13 metabolites were detected as differential metabolites between AH and CS, and between AH and RS, respectively. The relative abundance of phenylpropanoate (log₂fold change [FC]) = 1.30, 1.09), panthenol (log₂FC = 2.36, 2.20), threitol (log₂FC = 1.00, 1.07), and 3,7,12-trihydroxycoprostane (log₂FC = 0.79, 0.78) were greater in both CS and RS than in AH, and tyrosine (log₂FC = -0.32), phenylalanine (log₂FC = -0.30), and pyruvic acid (log₂FC = -0.30) were lower in RS than in AH. In the vein, 1 and 7 metabolites were detected as differential metabolites between AH and CS, and between AH and RS, respectively. By comparing AH and RS, we found that metabolic pathways of phenylalanine, tyrosine, and tryptophan biosynthesis and phenylalanine metabolism were enriched by integrative artery and vein analysis. Furthermore, AH and RS, arterial phenylpropanoate and 4-hydroxyproline were positively, and phenylalanine was negatively correlated with milk urea nitrogen. Finally, in AH and CS, arterial panthenol was negatively correlated with feed efficiency. Conclusion: Arterial metabolic profiles changed more than those in the veins from animals on three forage diets, differing in amino acids. We found that phenylalanine, tyrosine, and tryptophan biosynthesis and phenylalanine metabolism were restricted when cows were fed low-quality cereal straw diets.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3185-3190
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• 2016

Background: This study was designed to compare radioguided versus routine wire localization of nonpalpable non-malignant breast lesions in terms of efficacy for complete excision, ease of use, time saving, and cosmetic outcome. Materials and Methods: Patients with non-palpable breast masses and non-malignant core biopsy results who were candidates for complete surgical lumpectomy were enrolled and randomly assigned to radioguided or wire localization groups. Radiologic, surgical, and pathologic data were collected and analyzed to determine the difficulty and duration of each procedure, ease of use, accuracy, and cosmetic outcomes. Results: This prospective randomized study included 60 patients, randomly divided into wire guided localization (WGL) or radioguided occult lesion localization (ROLL) groups. The mean duration of localization under ultrasound guidance was shorter in the ROLL group (14.4 min) than in the WGL group (16.5 min) (p<0.001). The ROLL method was significantly easier for radiologists (p=0.0001). The mean duration of the surgical procedure was 22.6 min (${\pm}10.3min$) for ROLL and 23.6 min (${\pm}9.6min$) for WGL (p=0.6), a non-significant difference. Radiography of the surgical specimens showed 100% lesion excision with clear margins, as proved by pathologic examination, with both techniques. The surgical specimens were slightly heavier in the ROLL group, but the difference was not significant (p=0.06). Conclusions: The ROLL technique provides effective, fast, and simple localization and excision of non-palpable non-malignant breast lesions.

• Journal of Korean Academy of Nursing
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• v.50 no.2
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• pp.271-285
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• 2020

Purpose: This study examined the effects of a physical activity promoting program based on the Information-Motivation-Behavioral Skills (IMB) model on physical activity and health outcomes among obese older adults with knee osteoarthritis. Methods: This study utilized a randomized controlled trial with a convenience sample of 75 obese older adults with knee osteoarthritis in a university hospital. The older adults in the intervention group participated in a 12-week program involving weekly group sessions and monitoring calls with education booklets and video clips for exercise dances, while those in the control group received an usual care. Outcomes were measured using self-report questionnaires, anthropometrics, and blood analyses. The intervention effects were analyzed using Mann-Whitney U test and ANCOVA. Results: The mean age of participants was 74.9 years with 84.0% women. The intervention group at 12 weeks showed significantly greater improvements in self-efficacy for physical activity (F=81.92, p<.001), physical activity amounts (Z=-2.21, p=.044), knee joint function (F=15.88, p<.001), and health-related quality of life (F=14.89, p<.001) compared to the control group. Among obese-metabolic outcomes, the intervention group at 12 weeks showed a significant decrease in visceral fat mass (F=7.57, p=.008) and improvement in high-density level cholesterol (F=9.51, p=.003) compared to the control group. Conclusion: Study findings support the need for an IMB based physical activity program for promoting physical activity, knee function and health outcomes in obese older adults with knee osteoarthritis. Longitudinal studies are warranted to confirm the persistence of obese-metabolic effects in clinical settings.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.2
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• pp.131-138
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• 2010

This study determined the optimum microalgae species and concentration for the brackish water flea, Diaphanosoma celebensis, in individual and community cultures by feeding it several different diets. Six single trials (Tetraselmis suecica, Isochrysis galbana, marine Chlorella ellipsoidea, freshwater Chlorella vulgaris, Scenedesmus sp., Selenastrum sp.) were conducted at 10 psu and $30^{\circ}C$. The community and individual cultures of the water flea were performed in 1-L beakers and 3-mL vessels (12-well culture plates), respectively. In the community cultures, the maximum density and specific growth rate were highest for water fleas fed T. suecica, reaching 60.0 individuals (ind.)/mL and 0.40, respectively. In the individual cultures, the most offspring and greatest life span of females were 56.9 ind. and 24.3 days, respectively, in the T. suecica trial. By contrast, diets of Scenedesmus sp. and Selenastrum sp. resulted in poor growth rates. In the T. suecica experiments examining a range of 10 to $200\times10^3$ cells/indl. the specific growth rate of the water flea tended to increase with the amount of supplement, while the life span decreased. The maximum density and number of offspring of females was highest at 53.5 ind./mL and 38.8 ind. respectively, at 40,000 cells/ind. These results suggest that the best microalgae species for the mass culture of D. celebensis is T. suecica and the optimum concentration is 40,000 cells per individual.

• Preventive Nutrition and Food Science
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• v.21 no.3
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• pp.165-170
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• 2016

Recent trial results suggest that the consumption of a low glycemic index (GI) diet is beneficial in the prevention of high blood glucose levels. Identifying active hypoglycemic substances in ordinary foods could be a significant benefit to the management of blood glucose. It has been hypothesized that noodles with Bombyx mori powder are a low GI food. We evaluated GI and changes in postprandial glucose levels following consumption of those noodles and compared them with those following consumption of plain wheat flour noodles (control) and glucose (reference) in healthy subjects. Thirteen males (age: $34.2{\pm}4.5years$, body mass index: $23.2{\pm}1.1kg/m^2$) consumed 75 g carbohydrate portions of glucose and the 2 kinds of noodle after an overnight fast. Capillary blood was measured at time 0 (fasting), 15, 30, 45, 60, 90, 120, and 180 min from the start of each food intake. The GI values were calculated by taking the ratio of the incremental area under the blood glucose response curve (IAUC) for the noodles and glucose. There was a significant difference in postprandial glucose concentrations at 30 and 45 min between the control noodles and the noodles with Bombyx mori powder: the IAUC and GI for the noodles with Bombyx mori powder were significantly lower than those for glucose and plain wheat flour noodles. The wheat flour noodles with Bombyx mori powder could help prevent an increase in postprandial glucose response and possibly provide an alternative to other carbohydrate staple foods for glycemic management.

• Journal of Korean Academy of Nursing
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• v.46 no.1
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• pp.140-148
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• 2016

Purpose: This study was performed to determine the physical and psychological effects of an urban forest-walking program for office workers. For many workers, sedentary lifestyles can lead to low levels of physical activity causing various health problems despite an increased interest in health promotion. Methods: Fifty four office workers participated in this study. They were assigned to two groups (experimental group and control group) in random order and the experimental group performed 5 weeks of walking exercise based on Information-Motivation-Behavioral skills Model. The data were collected from October to November 2014. SPSS 21.0 was used for the statistical analysis. Results: The results showed that the urban forest walking program had positive effects on the physical activity level (U=65.00, p <.001), health promotion behavior (t= - 2.20, p =.033), and quality of life (t= - 2.42, p =.020). However, there were no statistical differences in depression, waist size, body mass index, blood pressure, or bone density between the groups. Conclusion: The current findings of the study suggest the forest-walking program may have positive effects on improving physical activity, health promotion behavior, and quality of life. The program can be used as an effective and efficient strategy for physical and psychological health promotion for office workers.