• Journal of Environmental Science International
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• v.20 no.6
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• pp.783-788
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• 2011

Different from the main land of South Korea, Jeju Island has been in difficulties for measuring discharge. Due to high infiltration rate, most of streams in Jeju Island are usually in the dried state except six streams with the steady base flow, and the unique geological characteristics such as steep slope and short traveling distance of runoff have forced rainfall runoff usually to occur during very short period of time like one or two days. While discharge observations in Jeju Island have been conducted only for 16 sites with fixed electromagnetic surface velocimetry, effective analysis and validation of observed discharge data and operation of the monitoring sites still have been limited due to very few professions to maintain such jobs. This research is sponsored by Ministry of Land, Transport and Maritime Affairs to build water cycle monitoring and management system of Jeju Island. Specifically, the research focuses on optimizing discharge measurement techniques adjusted for Jeju Island, expanding the monitoring sites, and validating the existing discharge data. First of all, we attempted to conduct discharge measurements in streams with steady base flow, by utilizing various recent discharge monitoring techniques, such as ADCP, LSPIV, Magnetic Velocimetry, and Electromagnetic Wave Surface Velocimetry. ADCP has been known to be the most accurate in terms of discharge measurement compared with other techniques, thus that the discharge measurement taken by ADCP could be used as a benchmark data for validation of others. However, there are still concerns of using ADCP in flood seasons; thereby LSPIV would be able to be applied for replacing ADCP in such flooded situation in the stream. In addition, sort of practical approaches such as Magnetic Velocimetry, and Electromagnetic Wave Surface Velocimetry would also be validated, which usually measure velocity in the designated parts of stream and assume the measured velocity to be representative for whole cross-section or profile at any specified location. The result of the comparison and analysis will be used for correcting existing discharge measurement by Electromagnetic Wave Surface Velocimetry and finding the most optimized discharge techniques in the future.

• Journal of the Korea Fashion and Costume Design Association
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• v.16 no.3
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• pp.201-217
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• 2014

There is likely to be a fit problem when women aged in their 30s-40s purchase down-age clothing from brands that target women in their 20s. To identify the part of the lower body that causes the fit problem, the sizes and types of lower body of women in their 30s-40s were compared with those of women in their 20s. The data for this study was from the 2010 Size Korea survey of body measurements of 1675 female adults in their 20s-40s. To examine differences in the average sizes of the lower body between women in their 20s and 30s-40s, descriptive statistics and t-tests were conducted. Factor and cluster analysis were used to classify body types by age groups. On the whole, compared to women in their 30s-40s, women in their 20s were found to be higher for all height items and smaller for size, thickness and width items. The result of the Glycemic index analysis showed that the body type of women in their 20s was generally larger than that of women in their 30s-40s. In addition, women in their 20s had a large drop value compared to those in their 30s-40s, whereas flatness of body cross section was bigger in the group of women in their 30s-40s. Four factors related to the lower body type of female adults in their 20s-40s were identified in the factor analysis, and three categories of body type were identified by cluster analysis. A Type 1 individual had abdominal obesity and chubby lower limbs, Type 2 had short legs and slightly chubby lower limbs, and Type 3 had long legs and a skinny lower body. A significant number of women in their 30s-40s were included in the Type 1 group, which was the least common category for women in their 20s.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.153-158
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• 2002

The effects of leveler on the copper trench filling were investigated during damascene plating process. To investigate the trench filling effect with the addition of a leveler, a cross-section images of the electroplated trenches with the width of$0.37{\mu}m,\;and\;0.18{\mu}m$ were observed by field emission scanning electron microscope (FE-SEM). Polyethylene glycol(PEG), 3-mercapto-1-propanesulfonic acid and Janus Green B were used as a carrier, an accelerator and a leveler. $0.37{\mu}m$ trenches were superfilled without voids, but there was voids formation in $0.18{\mu}m$ trenches when the leveler was not added into the electrolyte. On the other hand $0.18{\mu}m$ trenches were superfilled without voids with the addition of the leveler due to the reduction growth rate of copper at protrusions and edges, which yield smooth final deposit surface. The leverer effect becomes more significant as the width of trenches becomes smaller when trenches are filed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1760-1766
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• 2009

Physical properties of Yukwa base extruded with glutinous rice flour, rice flour, defatted soy flour, and salt using an twin-screw extruder were investigated. The ingredients were extruded at various moisture contents (16-18%), screw speeds (300 & 400 rpm) at 43.4 kg/hr feed rate. Length and specific volume of Yukwa base increased with decreasing moisture contents. Hunter's color L* values of Yukwa base was higher whereas $a^*\;and\;b^*$ values were lower with increasing moisture content. Water absorption index of Yukwa base increased with increasing moisture contents. X-ray diffraction of Yukwa base showed B type moisture content of 16% and 17% while it showed A type moisture content of 18%. Degree of crystallinity and breaking strength of Yukwa base were the lowest in the moisture content of 16% while the lowest value for hardness was found in the moisture content of 16% and of 17% with screw speed 400 rpm for all samples. In the microstructure of cross section of Yukwa base, air cell size was larger and cell wall was thicker as moisture content increased. The sensory evaluation of the Yukwa base showed that color and flavor were not significantly different among samples, while taste, appearance, mouth feel, and overall preference were higher as moisture contents decreased.

• Korean Journal of Social Welfare
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• v.68 no.2
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• pp.213-232
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• 2016

The purpose of this study is to explore the stress profile that adolescent perceives by using Latent Profile Analysis (LPA), and to examine the effect of characteristics variable per groups that appeared in profile. By using the cross-section data of 'A survey on the human right of Korean children and adolescent in 2013' issued by National Youth Policy Institute, the LPA concerning the stress type was conducted and surveyed 9,521 adolescents from fourth grade in elementary school to seniors in high school nationwide. The result of this study shows that two class types were selected according to the goodness-of-fit index and latent class classification rate. Type 1 is named low-risk group as they show low level, whereas type 2 is named relative risk group as they show high level. In order to predict the characteristics of adolescent stress, the study conducted Binary Logistic Regression analysis on the basis of low-risk group. There is higher probability to belong to relative risk group, the more they are female students than male students, the less their subjective health condition and happiness, the more runaway experience, the less school grades and the less economic affluence in their household. The implication of this research, its limitation and direction of follow-up research were suggested.

• Investigative Magnetic Resonance Imaging
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• v.4 no.1
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• pp.52-57
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• 2000

Purpose : The purpose of this study was to investigate the pattern of cerebral response to motor tasks in patients with schizophrenia compared with normal subjects using functional MRI. Materials and methods ; Nine right handed-schizophrenic patients and six right-handed normal subjects were included. We used right hand movement as task. Series of 120 consecutive echo-planar images per section were acquired during three cycles of task and rest activations. Lateralization index of cortical response was measured and compared between patients and normal subjects. Results ; Right hand motor task was associated with greater activation in left sensorimotor cortex than the right in normal subjects. Schizophrenia patients showed relatively decreased activation in left cortex and increased activation in right cortex compared with normal subjects. In one patient, reversed lateralization was noted. Conclusion : Normal hemispheric asymmetry of cortical response to motor task was found in different pattern in schizophrenia. Our result is consistent with functional disturbance of motor circuitry in this disorder. Functional MRI will play an important role in diagnosis and research of this disorder.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.63-71
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• 1968

Salted and dried yellow corvenia(Pseudosciaena manchurica), so called 'Gul-bi', is one of nation-widely consuming fish foo::ls. It is suitable for a long term preservation and its pro-duce is also a great deal on sea food processing in this country. The texture of 'Gul-bi', however, have often appeared to be a delicate factor for the quality of the product. The loss or dislocation of fat in the tissue of the fish resulted by salting and drying is believed to profoundly relate to the texture of product. In this paper, the tissue of yellow corvenia and movement of fat were microscopically observed before salting, immediately after salting, and after drying and the results observed in the tissues dry salted, brine salted, and brine salted with the addition of BHA were compared. The cross section of yellow corvenia muscle showed that a distinctive border by connective tissue between white and red muscle could not be seen in general, and red muscle was surrounded by hypodermic fatty tissues. In the tissue of fresh yellow corvenia, the fat was mainly distributed in hypodermic fat layer which located under the corium while rarely distributed in white muscle. It was found that some parts of the fat in the tissue were permeated into intermuscular tissue passing through the connective tissues during salting. The result Was the same in both dry-salting and brine-salting tissue. However, the fat translocated into intermuscular tissues disappeared during drying process in the salted without BHA tissues whereas in BHA added tissue. This result suggested that BHA may take a role of multiple effect in translocation of fat in tissues as well as in retarding oxidation. In an advanced stage of salted and dehydration, the muscle fibers were ajoined together and then limits between muscle fibers already became indistinguishable. And the migrated fat into intermuscular tissue aggregated around the connective tissue and are apt to gradually to flow out from the muscular system through these tissues.

• Composites Research
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• v.29 no.6
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• pp.408-413
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• 2016

Commonly-used polymers are manufactured as versatile forms. Furthermore, continuous polymer fibers are recently manufactured using nylon or aramid fiber. One of common epoxy was also used to make polymer fibers. Bisphenol-A type was used as base epoxy whereas amine and anhydride were used as hardeners. Epoxy fibers was cured by stepping up the temperature to maintain the shape of epoxy fiber. Surface energy was measured to confirm the degree of interfacial adhesion by modified static contact angle method. After mechanical properties were measured via fiber tensile test, the evaluation of fiber fracture was proceeded. Tensile strength of epoxy fiber using amine type hardener was higher as 138 MPa than anhydride case as 70 MPa. Fractured surface exhibited different failure patterns at the cross-section.

• Composites Research
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• v.31 no.5
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• pp.186-191
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• 2018

Condition and properties of composites with different chemical structure of epoxy matrix were observed after saline solution treatment. Epoxy was used as matrix and the flexibility was controlled by using 2 typed-epoxies and 3 types hardeners (amine, acid anhydride and amide). Saline water treatment was conducted with 6 wt% NaCl solution at $60^{\circ}C$ for 0, 15, and 30 days. Cross section was observed and interfacial and mechanical and properties was evaluated. Amine type exhibited the highest crosslinking density and mechanical and interfacial properties whereas water absorbance was lowest. It is because that the water molecules can be hardly penetrate into the epoxy matrix or the interface between epoxy and glass fiber and it leads to saline water resistance of composites.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.363-369
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• 2013

In this work, the effects of ozone treatments on mechanical interfacial properties of carbon fibers-reinforced nylon-6 matrix composites were investigated. The surface properties of ozone treated carbon fibers were studied by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). Mechanical interfacial properties of the composites were investigated using critical stress intensity factor ($K_{IC}$). The cross-section morphologies of ozone-treated carbon fiber/nylon-6 composites were observed by scanning electron microscope (SEM). As a result, $K_{IC}$ of the ozone-treated carbon fibers-reinforced composites showed higher values than those of as-received carbon fibers-reinforced composites due the enhanced $O_{1s}/C_{1s}$ ratio of the carbon fiber by the ozone treatments. This result concludes that the mechanical interfacial properties of nylon-6 matrix composites can be controlled by suitable ozone treatments on the carbon fibers.