• Fisheries and Aquatic Sciences
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• v.16 no.2
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• pp.117-124
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• 2013

We investigated the short-term and local changes in the thermohaline front in the Jeju Strait, Korea, which is usually formed during winter and spring. To do so, we compared Real-Time Observation System by Ferryboat (RTOSF) data with wind data and routinely collected oceanographic data. During February and April 2007, a thermohaline front formed in the Jeju Strait around the 13-$14^{\circ}C$ isotherms and 33.0-33.5 isohalines. The thermohaline was clearly weakened and began moving southward in mid-March. The variations in the surface temperature and salinity showed a continuous north-south oscillation of the thermohaline front with a period of 3-10 days. The speed of the short-term and local fluctuation of thermohaline front was about 5-30 cm/s. We confirmed these findings by examining the variation in the maximum temperature gradient and $14^{\circ}C$ isotherm during the study period. These short-term and local changes had not been previously detected using serial oceanographic and satellite data. Analysis of local wind data revealed a northerly wind fluctuation with a period of 3-10 days, which was clearly related to the short-term and local changes in the thermohaline front. The short-term and local changes of the thermohaline front in the Jeju Strait originated from local changes in the winter monsoon in this area.

• Ocean and Polar Research
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• v.26 no.3
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• pp.401-414
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• 2004

Temperature, salinity, alkalinity, pH, nutrient, chlorophyll, and iron were measured within the upper 250m water column around the Antarctic Polar Front in the Scotia Sea from late November to early December 2001. Temperature and salinity showed a rapid change across the Polar Front, and the temperature minimum layer existed only in the southern area of the Polar Front. Total $CO_2$ and nutrient concentrations were relatively high and increased rapidly with water depth in the southern area of the Polar Front, which was resulted from upwelling of the Antarctic deep water containing high concentrations of total $CO_2$ and nutrient. ${\Delta}C:{\Delta}N:{\Delat}P$ ratios measured in the norhem and southern areas of the Polar Front were 75:11.4:1 and 84:12.5:1, respectively, which were lower than the Redfield ratio. ${\Delta}Si:{\Delta}N$ ratio (3.65) measured in the southern area of the Polar Front was two times higher than that (1.95) in the northern area. These two ratios were higher than the ratio (1.0) measured in the temperate and tropical oceans. Chlorophyll concentrations were extremely high in the area of $59^{\circ}{\sim}60^{\circ}S$, which was attributed to favorable environmental conditions for phytoplankton growth in this area, such as sufficient iron, high water column stability, and high silicate concentration.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.3
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• pp.289-296
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• 2002

Using results obtained from field surveys in the outflow region of the Keum River in winter (February 22), spring (May 9), summer (July 31) and autumn (October 17) in 2000, it was described the nutrient front relating to the hydrography. It showed that the horizontal gradients was sharp in the distributions not only in salinity but also in nutrients in the region of the mouth of estuary far away about 20 km from the dyke of the Keum River during the year. The two layer structure was a ubiquitous feature in the inner estuarine side of the region showing the maximum horizontal gradients in salinity and nutrients. Although the absolute values in salinity and nutrient concentrations were distinguished by season, the nutrient front seperates the saltier and nutrients poor water in the open sea from the brackish and nutrients rich water of the plume. These results suggest that the nutrient front coincides with the esturine front in the region of freshwater influence (ROFI) of the Keum River.

• International Journal of Aerospace System Engineering
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• v.10 no.1
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• pp.1-13
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• 2023

The present study was attempted to investigate flow interference effects and the aerodynamic characteristics of the front and rear wings of a joined-wing aircraft by changing the configuration variables. The study was performed using a computational fluid dynamics(CFD) tool to demonstrate forward flight and analyze aerodynamic characteristics. A total of 9 configurations were analyzed with variations on the position, height, dihedral angle, incidence angle, twist angle, sweepback angle, and wing area ratio of the front and rear wings while the fuselage was fixed. The quantities of aerodynamic coefficients were confirmed in accordance with joined-wing configurations. The closer the front and rear wings were located, the greater the flow interference effects tended. Interestingly, the rear wing did not any configuration change, the lift coefficient of the rear wing was decreased when adjusted to increase the incidence angle of the front wing. The phenomenon was appeared due to an effective angle of attack alteration of the rear wing resulting from the flow interference by the front wing configurations.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.330-335
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• 2009

The principal objective of this study was to investigate changes in ice dendrite size during the freezing of tuna, in order to formulate a mathematical model of ice dendrite size. The tuna was frozen via a uni-directional heat transfer. Thermogram analysis allowed us to determine the position of the freezing front versus time, which is referred to as the freezing front rate. The morphology of the ice dendrites was assessed via scanning electron microscopy after freeze-drying, and the retained pore size was measured as ice dendrites. We noted that the mean size of ice dendrites increased with the distance to the cooling plate; however, it decreased with reductions in the cooling rate and the cooling temperature. In addition, shorter durations of the freeze-drying process decreased the freezing front rate, resulting in a larger size of the ice dendrite pores that operate as water vapor sublimation channels. According to our results, we could derive a linear regression as an empirical mathematical model equation between the ice dendrite size and the inverse of the freezing front rate.

• Fashion & Textile Research Journal
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• v.13 no.1
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• pp.116-129
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• 2011

The purpose of this study is to research on changes of body surface according to golf movements in designs of golf slacks pattern and reflect it to designs of golf slacks pattern to enhance adaptability. For the first stage of this study, length of body surface was analyzed by using 3D body shape. In second stage, analysis of wearing test of golf slacks is performed to extract major pattern design factor of golf slacks and then research patterns were designed. In third stage, 4 differently designed 1st, 2nd slacks were used for analysis of 3D Clothing air volume. The results of this research is as follow. The variation rate of body surface length according to golf swing posture resulted the longest on back swing posture and follow through posture. Waist circumference-omphalion, thigh and ankle circumference increased more than 10% of body surface during golf swing. Front waist circumference-omphalion, right waist to hip length, left waist to hip length and right back center length were decreased more than 10%. As a result of analysis on measurements of 1st slacks pattern design, waist front center getting in values, waist front center going down value, front hip width, and front crotch extension had similar industrial pattern design. Back center line angle, back crotch extension, and knee center point~back waist center point had significant differences. The designs and ease proposed for golf slacks pattern in this study are waist circumference 75.5 cm(1.8 cm, 2.38%), hip circumference 95 cm(2 cm, 2.11%), crotch length(front: -0.8 cm, -1.25%; rear: -1.8 cm, -2.83%), slacks length 96c m, gradient of C.B.L $10^{\circ}$, crotch extension (back 9.2~10.4 cm, front 3.2 cm).

• Journal of Environmental Science International
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• v.30 no.6
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• pp.475-485
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• 2021

This research investigated the characteristics of fine particles during cold front passage in Busan, on March 19, 2020. The cold front speed was 17.4 m/s (about 63k km/hr), moving from the northwest to the southeast, and with a width of about 64 km. The backward trajectory analysis showed that a southern sea air parcel flowed into Busan before the cold front passage, carrying continental materials from China transported into Busan after cold front passage. The PM₁₀ concentration in Busan showed a rapid increase after passing through the cold front, with PM_2.5 showing a high concentration during cold front passage. The PM_2.5/PM₁₀ ratio was 0.10 - 0.30. When the cold front passed, SO₄^2-, NO₃^-, Ca²⁺, NH₄⁺, Na⁺, and K⁺ in PM_2.5 showed a rapid increase, with SO₄^2- showing the most significant increase. These results indicated that understanding the characteristics of fine particles during cold front passage in Busan could provide insight into establishing a strategy to control urban air quality.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.12
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• pp.1015-1020
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• 2012

Resistance of the front electrode is the highest proportion of the ingredients of the series resistance in crystalline silicon solar cell. While resistance of the front electrode is decreased with larger area, it induces the optical loss, causing the conversion efficiency drop. Therefore the front electrode with high aspect ratio increasing its height and decreasing is necessary for high-efficiency solar cell in considering shadowing loss and resistance of front electrode. In this paper, we used the screen printing method to form high aspect ratio electrode by multiple printing. Screen printing is the straightforward technology to establish the electrodes in silicon solar cell fabrication. The several printed front electrodes with Ag paste on silicon wafer showed the significantly increased height and slightly widen finger. As a result, the resistance of the front electrode was decreased with multiple printing even if it slightly increased the shadowing loss. We showed the improved electrical characteristics for c-Si solar cell with repeatedly printed front electrode by 0.5%. It lays a foundation for high efficiency solar cell with high aspect ratio electrode using screen printing.

• The Research Journal of the Costume Culture
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• v.28 no.1
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• pp.1-14
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• 2020

This study is based on a representative body shape drawn from previous studies that classify adult male torso shapes. In this study, a design method is proposed by developing a tight-fit pattern that can be easily developed into various items and designs using the body surface development figure. This is obtained by converting the 3D body shape of the model representing the representative body shape. The specific design method was conducted as follows. Actual measurement values were used for waist back length, waist-to-hip length, shoulder length. The scye depth was determined as C/4-1.7 cm, and the front and back Interscye was set at (1/2 × actual measurements)-0.2 cm. The front-back neck breadth was set to (1/5 × base neck circumference)-1.3 cm and (1/5 × base neck circumference) cm. The front-back neck depth was set to (1/5 × base neck circumference)-1.2 cm and 3.5 cm. Front chest circumference was C/4-1 (front-back difference)cm; (1/4 × back chest circumference) was C/4 + 1 (front-back difference) + 0.3 (dart amount) cm. Front waist circumference was W/4-0.2 (front-back difference) + 2.2 (dart amount) cm; back waist circumference was W/4 + 0.2 (front-back difference) + 2.5 (dartamount) cm; front hip circumference was H/4 + 0.2 (ease) + 0.2 (front-back difference) cm; and back hip circumference was H/4 + 0.2 (ease)-0.2 (front-back difference) cm; Front droop was 1.6 cm. The newly developed tight-fit pattern is expected to be of great use as a basis for garment construction.

• Mycobiology
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• v.37 no.1
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• pp.10-16
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• 2009

The purpose of this study is to understand spatio-temporal changes of active fungal biomass and water in Tricholoma matsutake soil colonies during the mushroom fruiting season. The active fungal biomass was estimated by analyzing ergosterol content at four different points within four replicated locations in a single circular T. matsutake colony at Ssanggok valley in the Sogri Mt. National Park in Korea during 2003 to 2005. The four points were the ahead of the colony, the front edge of the colony and 20 cm and 40 cm back from the front edge of the colony. Ergosterol content was 0.0 to 0.7 ${\mu}g$ per gram dried soil at the ahead, 2.5 to 4.8 ${\mu}g$ at the front edge, 0.5 to 1.8 ${\mu}g$ at the 20 cm back and 0.3 to 0.8 ${\mu}g$ at the 40 cm back. The ergosterol content was very high at the front edge where the T. matsutake hyphae were most active. However, ergosterol content did not significantly change during the fruiting season, September to October. Soil water contents were lower at the front edge and 20 cm back from the front edge of the colony than at the ahead and 40 cm back during the fruiting season. Soil water content ranged from 12 to 19% at the ahead, 10 to 11% at the edge, 9 to 11% at the 20 cm back and 11 to 15% at the 40 cm back. Our results suggest that the active front edge of the T. matsutake soil colony could be managed in terms of water relation and T. matsutake ectomycorrhizal root development.