• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.3
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• pp.37-43
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• 2009

The objective of this study was to investigate the basic relationships between spectral reflectance and varying concentrations of sediment in surface waters. An experimental method for determining suspended sediment concentration (SSC) in the water by use of a spectroradiometer above the water surface, in visible and near-infrared (NIR) wavelengths, is applied. The main advantage of the method is the direct comparison of spectral reflectance and the SSC, but it requires an accurate knowledge of the water body and sediment. Therefore numerous spectroradiometric measurements are carried out in situ measurements, for SSC, ranging from zero to 100 percentage and two types of sediment applied in the water tank. The results indicate that the suspended sediment causes increasing spectral reflectance response in waters. We observed that spectral reflectance increases with SSC, first at the lower wavelengths (430-480 nm), then in the middle wavelengths (570-700 nm), and finally, in the NIR domain (800-820 nm); a characteristic maximum reflectance appears at 400-670 nm. Relationships between the wavelength, integral value, and the SSC were evaluated on the basis of the regression analysis. The regression curve for the relation between the wavelength, integral value, and the SSC were determined ($R^2$>0.98). Finally, the specular wavelength can be estimated to recognize the sediment and to improve SC estimation accuracy in the water.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.31-37
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• 2005

An attempt to improve the speed performance through the minimizing in wave resistance has been done by an application of gooseneck and no bulb type to bulbous bow for the DSME 78,500 Class LPG Carrier on the basis of the CFD calculation and comparatives model tests. The hydrodynamic characteristics according to the variation of the shape of Cp-curve, design load water line, frame line and bulbous bow that have an important effect on the wave resistance has been evaluated/calculated by ship-flow code. A wide variety in hull variation have been tried to have a good hull form with three types of fore-body hull forms mainly classified by the shape of bulbous bow. The speed performances for the three final hull forms with different bulbous bows have been evaluated through the model tests.

• Korean Journal of Community Nutrition
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• v.11 no.1
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• pp.63-71
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• 2006

The objective of this study was to evaluate whether nutrient intakes and serum biochemical indices are associated with the skin condition of humans. Anthropometric data, skin surface hydration, ceramide content, dietary intake of nutrients and serum lipids (total cholesterol, HDL-, LDL-cholesterol, TG, MDA: malondialdehyde, TAS: total antioxidant status) were obtained from 36 healthy young women. Subjects were classified into 2 groups {LM: Low Moisture Group (n = 20) , HM: High Moisture Group (n = 16)} by forehead skin hydration. The results of this study were as follows: The average age, BMI, total body water, LBM, body fat$\%$, WHR, forehead hydration, ceramide content were 20.2 yrs, 20.7, 28.81, 39.2 kg, $28.0\%$, 0.8, $44.3\%$, and 1.05 $\mu$g/$\mu$g protein, repectively. The intakes of SF A (saturated fatty acid) , MUFA (monounsaturated fatty acid) in the HM group were significantly higher (p < 0.05) than in the LM group, but zinc intakes in the LM group were higher than in the HM group. Serum levels of TAS in the LM group (1.27 mmol/l) were significantly higher (p < 0.05) than that of in the HM group (1.20 mmol/l). Whereas other lipid levels were not significantly different, intakes of vitamin $B_{6}$ and folate showed significant positive correlation with the forehead hydration (r = 0.447, r = 0.377). Intakes of calcium and phosphorus showed significant negative correlation with forearm ceramide content (r = -0.496, r = -0.485). Several associations between nutrient intakes and skin conditions were observed, indicating that changes in baseline nutritional status may affect skin health.

• Journal of Ocean Engineering and Technology
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• v.26 no.6
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• pp.53-58
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• 2012

An experimental study on the hydrodynamic performance of a backward bent duct buoy (BBDB) was performed in a 2D wave tank. The BBDB is one of the promising oscillating water column (OWC) types of floating wave energy converters. Two different corner-shaped BBDBs (sharp-corner and round-corner) were used to measure the maximum chamber surface elevations and body motions for various incident wave conditions, and their hydrodynamic characteristics were compared. In order to investigate the effect of the pneumatic pressure inside the chamber, the heave and pitch angle interacted with elevations were compared for both open chamber and partially open chamber BBDBs. From the comparison study, the deviation in the chamber surface elevations between the two shapes of BBDBs was found to be significant near the resonance period, which may be explained by viscous energy loss. It was also found that the pneumatic pressure noticeably affected the chamber surface elevation and body motions.

• Journal of Chest Surgery
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• v.26 no.2
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• pp.129-134
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• 1993

We compared postoperative results according to the different surgical approach in 180 cases of isolated ventricular septal defects operated at the department of Thoracic and Cardiovascular Surgery in Kyungpook University Hospital from January 1987 to December 1991. Of the 180 cases, 109 were males and 71 females, age ranging from 6 months to 15 years (mean: 5.6 years) and body weight ranging from 6 to 52㎏(mean : 20㎏). According to Soto's classification, perimembranous types were comprised of 119 cases (66％), doubly committed subarterial type 49 cases(27％), and muscular type 12 cases(7％). Patients were divided into three groups according to the incision methods: right atriotomy group (39％), right ventriculotomy group (47％), and pulmonary arteriotomy group (14％). The mean aortic cross clamp time was shorter in right atriotomy group (39 min.) than right ventriculotomy group (79min.) in the cases of large perimembranous VSD (P＜0.001). Spontanous recovery rate of cardiac rhythm after VSD closure was higher in right atriotomy group (51％) than right ventriculotomy group (32％) in the cases of perimembranous VSD (P＜0.05). The incidence of postoperative RBBB was 17.6％ with no statistical differences between right atriotomy group(17.9％) and right ventriculotomy group(19.2％). Overall mortality rate was 5.6％(10 cases) with no significant differences according to surgical approach.

• Wind and Structures
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• v.37 no.1
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• pp.57-78
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• 2023

In this study, a generalized three-degree-of-freedom (3-DoF) analytical model is formulated to predict linear aerodynamic instabilities of a prism under quasi-steady (QS) conditions. The prism is assumed to possess a generic cross-section exposed to turbulent wind flow. The 3-DoFs encompass two orthogonal horizontal directions and rotation about the prism body axis. Inertial coupling is considered to account for the non-coincidence of the mass center and the rotation center. The aerodynamic force coefficients-drag, lift, and moment-depend on the Reynolds number based on relative flow velocity, angle of attack, and the angle between the wind and the cable. Aerodynamic forces are linearized with respect to the static equilibrium configuration and mean wind velocity. Routh-Hurwitz and Liénard and Chipart criteria are used in the eigenvalue problem, yielding an analytical solution for instabilities in galloping and static divergence types. Additionally, the minimum structural damping and stiffness required to prevent these instabilities are numerically determined. The proposed 3-DoF instability model is subsequently applied to a conductor with ice accretion and a full-scale dry inclined cable. In comparison to existing models, the developed model demonstrates superior prediction accuracy for unstable regions compared with results in wind tunnel tests.

• Journal of the Korean Society of Costume
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• v.61 no.9
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• pp.15-26
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• 2011

The study compared and analyzed the physical figures of Korean women, who are in their 60's, living in Korea and those living in Japan. Results are as follow: 1. Korean women, in their 60's, living in Korea were compared with their counterparts living in Japan across 52 items of body measurements, 25 of which have been found to be different. 2. Factor analysis was conducted with the body measurements of the two groups. The analysis results found no big differences between them. 3. Cluster analysis was performed with the factor points of the two groups, and the analysis results identified three types for both of the parties. Korean women living in Korea can be identified as those who were tall and weighed average, those who were average tall and weighed little, and those who were in average height and weighed a lot. On the other hand, Korean women living in Japan can be identified as those who were short and weighed little, those who were in average height and weighed a lot, and those who were tall and weighed average. The result of the study indicates distinctive differences between the two groups, and suggests that people of the same race can have differences in their physical figures due to many factors including socio-cultural and dietary differences when they live in different places over extended period of time.

• Journal of Mushroom
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• v.12 no.2
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• pp.82-87
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• 2014

Commonly known as the button mushroom, Agaricus bisporus is one of the most widely cultivated mushroom species of edible fungi. In the breeding of new button mushroom, Seolwon was developed by crossing two homokaryons. Because of the predominantly pseudohomothallic life cycle, only a small percentage of homokaryotic meiospores are produced, which do not fruit. Homokaryotic cultures derived from these types of single spores produce a vegetative mycelium that contain a variable number of genetically identical nuclei per cell. After crossing two homokaryons, hybrids were cultivated on a small scale and on a commercial scale at a farm. The spawn was made by a commercial spawn producer and the spawned compost by a commercial compost producer. Mycelial growth of Seolwon on CDA was better at $25^{\circ}C$ when it was compared with that of Seolgang. The mature cap shape of new strain Seolwon is oblate spheroid and the immature cap shape is round to oblate spheroid. The cap diameter was 39.7 mm on average. In comparison with white strain Seolgang, the strain had a yield that was 11% higher. It produced fruiting bodies which had a higher weight on average per fruiting body and were 9.7% firmer with a good shelf life. Days of fruiting body were 1-2 days later than those of Seolgang. The physical characteristics such as springiness, chewiness, adhesiveness, gumminess were better than that of Seolgang.

• Journal of Astronomy and Space Sciences
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• v.28 no.1
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• pp.37-54
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• 2011

Two semi-analytic solutions for a perturbed two-body problem known as Lagrange planetary equations (LPE) were compared to a numerical integration of the equation of motion with same perturbation force. To avoid the critical conditions inherited from the configuration of LPE, non-singular orbital elements (EOE) had been introduced. In this study, two types of orbital elements, classical Keplerian orbital elements (COE) and EOE were used for the solution of the LPE. The effectiveness of EOE and the discrepancy between EOE and COE were investigated by using several near critical conditions. The near one revolution, one day, and seven days evolutions of each orbital element described in LPE with COE and EOE were analyzed by comparing it with the directly converted orbital elements from the numerically integrated state vector in Cartesian coordinate. As a result, LPE with EOE has an advantage in long term calculation over LPE with COE in case of relatively small eccentricity.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.41.3-41.3
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• 2015

As part of the Herschel key program "Water in Star-forming Regions with Herschel (WISH)", PACS imaging spectroscopy data have been taken toward ten massive young stellar objects (YSOs): four high mass protostellar objects (HMPOs), two hot molecular cores (HMCs), and four ultracompact HII regions (UCHIIs). The spectra cover a broad range of wavelengths (55 to 210 micron) presenting various atomic and molecular lines as well as excellent dust thermal continua. By fitting the continua utilizing a modified black-body formula we estimate mass-weighted temperature and column density distributions of warm dust and find that UCHII regions are warmer and HMCs are more deeply embedded than the other types. We also estimate rotational temperature and column density distributions of warm CO gas using the rotational diagram analysis. In addition, based on the comparison of high J CO line fluxes to the RATRAN estimates of central heating envelope models, we find that majority of warm CO is originated from bipolar outflow shocks.