• Journal of the Korean Society for Precision Engineering
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• v.27 no.2
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• pp.130-136
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• 2010

For stability analysis of the lumbar spine, the hypothesis presented is that the disc has stress sensors driving feedback mechanism, which could react to the imposed loads by adjusting the contraction of the muscles. Fusion in the motion segment of the lumbar spinal column is believed to alter the stability of the spinal column. To identify this effect finite element (FE) models combined with optimization technique was applied and quantify the role of each muscle and reaction forces in the spinal column with respect to the fusion level. The musculoskeletal FE model was consisted with detailed whole lumbar spine, pelvis, sacrum, coccyx and simplified trunk model. Vertebral body and pelvis were modeled as a rigid body and the rib cage was constructed with rigid truss element for the computational efficiency. Spinal fusion model was applied to L3-L4, L4-L5, L5-S1 (single level) and L3-L5 (two levels) segments. Muscle architecture with 46 local muscles was used as acting directions. Minimization of the nucleus pressure deviation and annulus fiber average axial stress deviation was selected for cost function. As a result, spinal fusion produced reaction changes at each motion segment as well as contribution of each muscle. Longissimus thoracis and psoas major muscle showed dramatic changes for the cases of L5-S1 and L3-L5 level fusion. Muscle force change at each muscle also generated relatively high nucleus pressure not only at the adjacent level but at another level, which can explain disc degeneration pattern observed in clinical study.

• Journal of Korean Society of Steel Construction
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• v.10 no.2 s.35
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• pp.201-209
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• 1998

The presence of elevated temperature can alter significantly the structural response of fibre-reinforced laminated composites. A thermal environment causes degradation in both strength and constitutive properties, particularly in the case of fibre-reinforced polymeric composites. Furthermore, associated thermal expansion, either alone or in combination with mechanically induced deformation, can result in buckling, large deflections, and excessively high stress levels. Consequently, it is often imperative to consider environmental effects in the analysis and design of laminated systems. Exact analytical solutions of higher-order shear deformation theory is developed to study the thermal buckling of cross-ply and antisymmetric angle-ply rectangular plates. The buckling behavior of moderately thick cross-ply and antisymmetric angle-ply laminates that are simply supported and subject to a uniform temperature rise is analyzed. Numerical results are presented for fiber-reinforced laminates and show the effects of ply orientation, number of layers, plate thickness, and aspects ratio on the critical buckling temperature and compared with those obtained using the classical and first-order shear deformation theory.

• Korean Journal of Community Nutrition
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• v.6 no.5
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• pp.819-829
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• 2001

The purpose of this study was to investigate the difference of general characteristics, menopause status, dietary patterns and nutrient intakes between women aged from 30 to 65 years old with a hypercholesterolemia group and normocholesterolemia group. The subjects were classified as belonging to the hypercholesterolemia group or normocholesterolemia group barred on The Guidelines for Korean Hyperlipidemia. Dietary intakes of fatty acids were measured by means of a 24-hr recall method with food models and measuring tools. We analyzed both data sets together using analysis of variance chi-square test and student's t-test(SPSS for WINDOWS, version 7.5). Significance was defied as a p value < 0.05. The results obtained are summarized as follows. Mean age and BMI of the hypercholesteroemia group were significantly higher than those of the normocholesterolemia group. Intakes of cereal, vegetables, mushrooms and sea food in the normocholesterolemia group were significantly higher than those in the hypercholesterolemia group. Most of the nutrient intakes were not significantly different between the normocholesterolemia group and the hypercholesterolemia group. However, vitamin E intake of the normocholesterolemia group was significantly higher than that of the hypercholesterolemia group. There was a significant negative correlation between vitamin E intake and serum TC(r = -.363, p < 0.001) and LDL-C(r = -.359, p < 0.001). In addition, Serum TG had significantly correlation with carbohydrate(r = 0.137, p < 0.001) and vitamin E intake(r = -0.134, p < 0.001). Therefore, women who suffered from hypercholesterolemia were recommended to control body weight, and to consume foods containing high vitamin E and foods containing high dietary fiber such as vegetables, mushrooms, and sea food.

• Journal of the Korean Society of Clothing and Textiles
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• v.1 no.1
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• pp.25-29
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• 1977

The warmth retentivity of natural and syntheic waddings as bedding stuff, and further, the machanism of heat transmission through conduction, radiation and convection were analysed. The materials used were cotton, silk, and wool as natural waddings, and polyamide, polyester, regular acrylic, conjugate acrylic, regular polyprepylene and conjugate polypropylene as synthetic waddings. The results of this study are as follow: 1. The warmth retentivity is highest in silk. Following silk in descending order is cotton, conjugate acrylic, polyester, regular acrylic, wool, polyamide, conjugate polypropylene and regular polypropylene. There is not any significant relationship between warmth retentivity and the conductivity of the fibers. 2. Transmission by radiation through the fiber waddings is highest in conjugate polypropylene. Following conjugate polypropylene in descending order is regular polypropylene. polyester. polyamide, conjugate acrylic, regular acrylic, wool, cotton, and silk. This is seen to be in nearly reversed order to the abovementioned order of warmth retentivity. In this respect, warmth retentivity with loose fibreous material as in the case of bedding stuff is primarily affected by the interceptive function of the fibers in heat radiation. 3. Warmth retentivity becomes lower with increasing air content of the waddings. This is because heat transmission by radiation incrases as air content increases. The air content increase is due to the fact that the air is unable to intercept heat radiation. In addition, heat transmission accelates in proportion to the increase in convection as the air gap enlarges.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.4
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• pp.292-301
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• 2010

For an effective management of fisheries resources, it is very important that to make clean inhabitation environment and to preserve fisheries resources. The material which is mainly used as fishing gear in modern times, is polyethylene, polypropylene, polyamide, etc., chemical fiber. And lost fishing gears which are make of these, occur ghost fishing and ocean pollution. To solve these problem, we development biodegradable fishing trap using the polybutylene succinate (PBS). Developed traps are for red snow crab (Chionoecetes japonicus) and shrimp, major traps in the East Sea, and we carried out fishing research using two kind traps in the coastal sea of Ayajin-port (Goseong) to analysis fishing efficiency of PE trap and PBS trap. As a result for fishing experiment (year 2005-2006) of red snow crab trap, two kind traps were almost the same in catches and length composition. During a experiment, parts of meshes, used for over 1 year, were cut by biodegradation. As a result for fishing experiment (year 2007) of shrimp trap, northern shrimp (Pandalus eous), coonstripe shrimp (Pandalus hypsinotus) and morotoge shrimp (Pandalopsis japonica) were catched, and the almost is northern shrimp. Two kind traps were almost the same in catches and length composition. In accordance with these result, it is recommended that the developed traps are have to commercialized because the fishing powers of PE traps and PBS traps were same. But biodegradation speed is have to controled in consideration of ocean microorganism volume and traps life.

• Journal of the Korean Society of Food Culture
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• v.29 no.5
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• pp.464-475
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• 2014

Eating breakfast provides crucial nutrition for brain function and helps promote overall health. It is especially critical in growing adolescents, as it is known to form good eating habits and better study habits. This study investigated the effects of skipping breakfast on nutritional state, fatigue level, and attention level. A cross-sectional study was conducted in 2010 on total of 828 adolescents composed of 414 boys and 414 girls. Students who ate breakfast never to twice per week were placed in the breakfast-skipper group while students who ate breakfast more than five times per week were included in the breakfast-eater group. Students performed a self-reported questionnaire on food behaviors, amount of food consumption, fatigue level, attention deficient hyperactivity disease (ADHD) level by Conners-Wells' Adolescent Self-Report Scales, depression scale, and self-esteem level. Statistical analysis was conducted using the SAS program (version 9.1). A total of 135 boys (32.6%) and 138 girls (33.3%) were included in the breakfast-skipper group, whereas 241 boys (58.2%) and 223 girls (53.9%) were included in the breakfast-eater group. The breakfast-skipper group showed irregular food behaviors and lacked nutrients. Specifically, energy (p< .001), protein (p< .001), dietary fiber (p< .001), calcium (p< .01), vitamin A (p< .01), thiamin (p< .05), niacin (p< .001) levels in boy breakfast-skippers were statistically lower compared to boy breakfast-eaters. Intakes of all nutrients except fat in girl breakfast-skippers were statistically lower than in girl breakfast-eaters. Girl breakfast-skippers (41.3%) showed significantly higher fatigue risks compared to girl breakfast-eaters (21.5%). Low attention level was also observed only in girls in the breakfast-skipping group. Moreover, students in the breakfast-skipper group showed higher scores for depression and low self-esteem (p< .001). In conclusion, skipping breakfast has effects on young adolescents' nutrition, manifesting as high fatigue level and low attention level, especially in girls.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.5
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• pp.39-47
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• 2016

The houses are formed in the lower part of the mountain slope face in most agricultural areas of Korea, and old residents accounting for a large portion of the agricultural populations cannot respond to the evacuation quickly when the landslide happens, and the possibility the life damage occurs is high. Therefore, it is urgent to arrange the measure on this. This study is intended to develop the personal disaster evacuation apparatus that can be installed in the house to minimize the life damage by the landslide and to develop the self-initiative evacuation apparatus. This study suggested the load applicable to the personal disaster evacuation apparatus by quantitatively analyzing the effect of the load of rockslides and avalanches caused by the landslide on the structure. Also, the material property of materials was calculated through the tension and bending intensity test after making the specimen of glass fiber reinforced plastic (GFRP) member. The load weight and material property drawn from this study can be used as the basic material for the stability analysis of the personal disaster evacuation apparatus.

• Food Science of Animal Resources
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• v.37 no.1
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• pp.29-37
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• 2017

Defatted bovine liver (DBL) is a potential source of protein and minerals. Supercritical carbon dioxide ($SC-CO_2$) and a traditional organic solvent method were used to remove lipid from bovine liver, and the quality characteristics of a control bovine liver (CBL), bovine liver defatted by $SC-CO_2$ ($DBLSC-CO_2$) at different pressures, and bovine liver defatted by organic solvent (DBL-OS) were compared. The $DBLSC-CO_2$ samples had significantly higher (p<0.05) protein, amino acid, carbohydrate, and fiber contents than CBL and DBL-OS. There was a higher yield of lipid from CBL when using $SC-CO_2$ than the organic solvent method. SDS-PAGE analysis demonstrated that the CBL and $DBLSC-CO_2$ had protein bands of a similar intensity and area, whereas DBL-OS appeared extremely poor bands or no bands due to the degradation of proteins, particularly in the 50 to 75 kDa and 20 to 25 kDa molecular weight ranges. In addition, $DBLSC-CO_2$ was shown to have superior functional properties in terms of total soluble content, water and oil absorption, and foaming and emulsification properties. Therefore, $SC-CO_2$ treatment offers a nutritionally and environmentally friendly approach for the removal of lipid from high protein food sources. In addition, $SC-CO_2$ may be a better substitute of traditional organic solvent extraction for producing more stable and high quality foods with high-protein, fat-free, and low calorie contents.

• Journal of the Korean Home Economics Association
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• v.46 no.3
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• pp.27-36
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• 2008

This study was conducted to investigate the recognition and uses of Codonopsis lanceolata. A survey methodology was employed consisted of 37.8% males and 62.2% females from the Seoul and Kyunggido area. The main results are as follows: The majority of respondents 60.7% males and 74.1% females indicated a preference for Korean food across all generational age classes. The specific preference for codonopsis lanceolata was indicated by the majority of males individuals in the forty to age group and by the teenage to thirty age bracket. The most popular reason provided for the preference of codonopsis lanceolata was good health benefits. People indicating a dislike for codonopsis lanceolata had little previous experience of eating this plant. Codonopsis lanceolata also appeared in 7.9% males and 9.0% females of small food transactions with 37.0% males and 36.6% females of respondents indicating supermarkets and traditional markets as their preferred shopping locations. In relation to cooking methods roasting was nominated by 36.0% males and 49.3% females of respondents. Codonopsis lanceolata was acknowledged as having the following characteristics "prevention of adult disease", "low calorie the diet food", and "high dietary fiber", but was not associated with "good flavor" and "established cooking method", "good health benefits from saponin", and "good for alexipharmic and expectorant". Recognition and eating experience was low for codonopsis lanceolata kimchi and Kimchi, rice bread, bread and sauce added with codonopsis lanceolata. However the opinion of taste appeared highly among respondents, especially in the twenties and teenage age groups.

• Transactions on Electrical and Electronic Materials
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• v.13 no.6
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• pp.310-316
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• 2012

A new method for early caries diagnosis was proposed and tested through a home-made optical examination system that used quantitative light fluorescence (QLF) and digital imaging fiber optic transillumination (FOTI) (DIFOTI), with light sources across a wide spectral range, from 350 nm to 1,000 nm. The front-illuminated infrared light scattering image (FIR) showed similar diagnostic abilities to that of DIFOTI. The FIR method was invented based on the observation that caries lesions lose the high transmittance and low scattering properties of benign enamel tissue. There are various methods for the early diagnosis of caries, such as visual examination, exploration, X-ray radiography, QLF, FOTI, and infrared fluorescence (diagnodent). Among them, methods based on optical properties are regarded as having the most potential. A comparative study was performed between the FOTI, QLF, diagnodent, optical coherence tomography, and FIR scattering image methods, using 20 extracted teeth samples with early caries. A scale of lesion measurement based on optical image contrast was proposed. The statistical analysis showed a significant correlation between the DIFOTI and FIR methods (r = 0.35, p < 0.05). However, the QLF and diagnodent methods showed little association with FIR images, as they have different detection principles as compared with FIR. Tomographic images obtained by OCT, using 1,330 nm super luminescent LED as a gold standard of tooth structure, verified that the FOTI and FIR results correctly represented the lack of homogeneity in dental tissue. The newly proposed FIR method attained similar diagnostic results to those of FOTI, but with an easier approach.