• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.5
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• pp.491-497
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• 2015

This paper reports an experimental study for evaluating the effect of temperature on the mode I, mode II and mixed-mode interlaminar fracture toughness of adhesive joints with a curved cross-section of filament-wound dome-separated composite pressure vessel. Mode I and mixed-mode interlaminar fracture toughness were evaluated using DCB specimens, while mode II interlaminar fracture toughness was determined using ENF specimens. $[{\pm}10^{\circ}]_6$, $[{\pm}27^{\circ}]_6$ and ($[{\pm}10^{\circ}]_3/FM73/[{\pm}27^{\circ}]_3$) winding specimens with the curved cross-section were considered. In-situ temperature environments were simulated with a range of $-30^{\circ}C-60^{\circ}C$ using an environmental chamber and furnace. Experimental results on the effect of temperature indicate that interlaminar fracture toughness tends to be high at low temperature and is degraded with increase in temperature. For specimen types, it was found that interlaminar fracture toughness of $[{\pm}10^{\circ}]_3/FM73/[{\pm}27^{\circ}]_3$ winding specimens considered as adhesive joints of dome and helical part was higher than other specimens.

• Journal of Ginseng Research
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• v.33 no.3
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• pp.189-193
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• 2009

The researchers studied the composition of latent buds by surveying the embryo of harvested seed, and the developmental pathway of latent buds by analyzing the characteristics of local ginseng. One-year-old ginseng seedlings were transplanted into the field and harvested two years later. The developmental pathway of the main bud, which would be the shoot of ginseng in the fourth year, was also investigated. The main bud of the seedling was formed from the region between root and shoot of the germinating seed. Primary and axillary latent buds protruded in a dome-shape from the cortex and separated from the main bud. Ninety percent of the single main bud was derived from the primary latent bud. Twin main buds were derived from a primary latent bud and one axillary bud, and triple main buds were derived from primary latent bud and two axillary latent buds. In the field, the researchers could not find 2-stem plants in 2-3 years old plants. However, the researchers found a 2-stem plant in a 4-year-old plant because its two main buds developed from a 3-year-old plant. We can conclude that a 2-stem plant was observed in the plant that was at least 4 years old. The main buds of the 4-year-old plant were formed at the primary and axillary latent bud of seed and cortex, the latent bud of rhizome in a 2-3 year old plant. In older plants, twin and triple main buds were derived mostly from the cortex latent bud than the primary latent bud.

• Korean Journal of Veterinary Research
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• v.34 no.4
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• pp.695-703
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• 1994

The development of reticulum in fetuses between 60, 90, 120 days of gestation and neonates of Korean native goats was investigated by light, scanning electron microscopy. The results were summarized as follows; 1. In the 60-day-old fetuses, the stomach was developed and differentiated into four compartments of rumen, reticulum, omasum, and abomasum. The reticular epithelial layers were differentiated into two zones; a small dark basal and a large light luminar zones. The wall of reticulum resembled that of the rumen except that the mucosa was in the cranio-dorsal region of the reticulum. 2. In the 90-day-old fetuses, the light luminar zone of the reticulum was about 10-16 times thicker than the dark zone. The outlines of the reticular ribs were visible. 3. In the 120-day-old fetuses, the wall of the reticlum had also increased in thickness. The reticular mucosa exhibited an irregular luminar surface and the invaginations had differentiated into large regularly arranged ones separated by 3-5 and small irregularly arranged ones. 4. In the neonate, the luminar surface of the reticular mucosa demonstrated clear furrows, at which the superficial cells of the light zone had undergone degenerative changes. 5. Scanning electron microscopic studies; In the 60-day-old fetuse, numerous microvilli were observed on the superficial epithelial layer of shape or dome like at 120 days. In the neonate, the reticular papillae liked the little finger.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.2
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• pp.351-373
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• 2019

The cold eddies around the Ulleung Basin in the East Sea were identified from satellite altimeter sea level data using the Winding-Angle method from 1993 to 2015. Among the cold eddies, the Dokdo Cold Eddies (DCEs), which were formed at the first meandering trough of the East Korea Warm Current (EKWC) and were pinched off to the southwest from the eastward flow, were classified and their migration patterns were analyzed. The vertical structures of water temperature, salinity, and flow velocity near the DCE center were also examined using numerical simulation and observation data provided by the Hybrid Coordinate Ocean Model and the National Institute of Fisheries Science, respectively. A total of 112 DCEs were generated for 23 years. Of these, 39 DCEs migrated westward and arrived off the east coast of Korea. The average travel distance was 250.9 km, the average lifespan was 93 days, and the average travel speed was 3.5 cm/s. The other 73 DCEs had moved to the east or had hovered around the generated location until they disappeared. At 50-100 m depth under the DCE, water temperature and salinity (T < $5^{\circ}C$, S < 34.1) were lower than those of ambient water and isotherms made a dome shape. Current faster than 10 cm/s circulates counterclockwise from the surface to 300 m depth at 38 km away from the center of DCE. After the EKWC separates from the coast, it flows eastward and starts to meander near Ulleungdo. The first trough of the meander in the east of Ulleungdo is pushed deep into the southwest and forms a cold eddy (DCE), which is shed from the meander in the south of Ulleungdo. While a DCE moves westward, it circumvents the Ulleung Warm Eddy (UWE) clockwise and follows U shape path toward the east coast of Korea. When the DCE arrives near the coast, the EKWC separates from the coast at the south of DCE and circumvents the DCE. As the DCE near the coast weakens and extinguishes about 30 days later after the arrival, the EKWC flows northward along the coast recovering its original path. The DCE steadily transports heat and salt from the north to the south, which helps to form a cold water region in the southwest of the Ulleung Basin and brings positive vorticity to change the separation latitude and path of the EKWC. Some of the DCEs moving to the west were merged into a coastal cold eddy to form a wide cold water region in the west of Ulleung Basin and to create a elongated anticlockwise circulation, which separated the UWE in the north from the EKWC in the south.