• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.6
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• pp.1074-1087
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• 2022

This study reports an optimization of a 3D printed wrist brace (WB) for various tilting angles (0°, 45°, 90°) of the re-entrant (RE) pattern and thickness (2 mm, 4 mm) using thermoplastic polyurethane (TPU) filaments and thermoplastic elastomer (TPE) filaments. The actual printing time, weight, Poisson's ratio, and tensile property of the manufactured samples were analyzed. The results confirmed that the actual printing time and weight increased with increasing thickness, regardless of the filament type. All tilting angles of the WB showed a negative Poisson's ratio (NPR), the largest of which appeared at 90°. The results of the tensile property analysis showed that a 90° tilting angle also had the largest value of elongation and stress. From these results, we conclude that the most suitable wrist brace is one in which the actual printing time is low, the weight is minimized to a thickness of 2 mm, and the tilting angle of the RE pattern is 90° for good shock absorption. The choice of filaments may be decided upon according to the user's preference, since the TPU is stiff and the TPE is elastic.

• 대한치과보철학회:학술대회논문집
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• 2003.04a
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• pp.90-90
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• 2003

• 대한핵의학회:학술대회논문집
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• 1966.11a
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• pp.90.1-90.1
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• 1966

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2005.12a
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• pp.90-90
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• 2005

• Korean Journal of Pharmacognosy
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• v.30 no.2
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• pp.137-144
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• 1999

Torilin was isolated from haxane fraction of Torilis Fructus extract. Torilin produced inhibition of the acetic acid-induced and phenylquinone-induced writhing syndrome at the oral doses of 30 and 90 mg/kg in mice. It also increased the pain threshold at the oral doses of 30, 90 and 270 mg/kg in the tail pressure method and the Randall-Selitto method. However, it did not show a hypothermic action at the oral doses of 30 and 90 mg/kg in mice. The compound exhibited strong anticarrageenan activity at the oral doses of 90 and 270 mg/kg in rats, and had inhibitory effect on the vascular permeability at the oral doses of 30 and 90 mg/kg in mice. It also showed potent inhibition of leucocyte emigration in CMC-pouch at the doses of 3 and 9 mg/rat, sc. The acute toxicity of torilin was very weak: the $LD_{50}$ values were more than 5000 mg/kg, po and 2000 mg/kg, ip in mice. From the above mentioned results, it was suggested that torilin had potent analgesic and anti-inflammatory activities.

• Journal of Aquaculture
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• v.6 no.2
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• pp.63-69
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• 1993

Various scales of red tides have frequently occurred in the southern coastal waters of the Korean Penninsula since the late 1970's. Because most shellfish and finfish farms in Korea are located in the southern coastal waters, the impacts of red tides on the aquaculture have been increasing significantly. The Puksin Bay is one of the places where red tides have occurred almost every year since the early 1980's. During $1990\~1991$, mass mortalities of aquacultural species by the red tides were recorded. The causative organisms in this period were Leplocylindrus danicu(November '90 and June '91), Skeletonema costatum(December '90 and August '91), Nitzschia seriata(August '91), and Gymnodinium splendens(July '91). The maximum chlorophyll-a content was $265.7{\mu}g/l$ in the tides. Frequent red tides are associated with the eutropication of the bay. Some relationships between red tides' occurrence and europhication are herein discussed.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.2
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• pp.183-189
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• 1987

The performance of frame synchronization can be represented by the values of three characteristic variables-average misframe interval, average syncloss detection time, average reframe time. In this paper, we have analyzed the performance of frame synchronization of the standardized 90Mb/s optical transmission system by Markov chain method, with the suggestion of an extended algorithm for performance improvement. Maximum average reframe time of 1.18 ms can be obtained by the suggested algorithm, which is compared with that of 2.28 ms for the existing algorithm.

• 에너지협의회보
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• s.11
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• pp.32-36
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• 1989

• Journal of the Korean Society of Safety
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• v.30 no.6
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• pp.12-17
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• 2015

In this study, the collapse characteristic of CFRP/Al compound square tube was investigated experimentally. The conclusions are as follows; The impact collapse characteristic of CFRP/Al compound square tube was found to be the most superior stacking conditions $[90^{\circ}]_8$. It showed that a very stable collapse mode was crushing. In the member with $[0_2{^{\circ}}/90_2{^{\circ}}]_s$ and $[90_2{^{\circ}}/0_2{^{\circ}}]_s$, stacking conditions, $0^{\circ}$ fibers were splayed to the external by laminar bending, while the $90^{\circ}$ fibers were held between the folds of the aluminum member by laminar bending, local buckling and transverse crack. In the member with $[45_2{^{\circ}}/45_2{^{\circ}}]_s$ stacking conditions, fibers were held between the folds of the aluminum member by local buckling and transverse crack.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.1
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• pp.79-85
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• 2006

CFRP(Carbon Fiber Reinforced Plastics) of the advanced composite materials as structural materials for vehicle, has a wide application in light-weigh structural materials of airplanes, ships and automobiles because of high strength and stiffness, However, there is a design variable to be considered in practical application of the laminate composite materials, these materials are vulnerable to transverse impact. This paper is to study the effects of stacking sequence and curvature on the penetration characteristics of composite laminate shell. They are stacked to $[0_3/90_3]S,\;[90_3/0_3]s\;and\;[0_2/90_3/0]s,\;[90_2/0_3/90]s$ and their interlaminar number two and four. They are manufactured to various curvature radius (R=100, 150, 200mm and $\infty$), When the specimen is subjected to transverse impact by a steel ball, the velocity of the steel ball was measured both before and after impact by determing the time for it to pass two ballistics-screen sensors located a known distance apart. The critical penetration energy of specimen A and B with less interfaces were a little higher than those of C and D. As the curvature increases, the critical penetration energy increases linearly because the resistance to the in-plane deformation as well as bending deformation increases, which need higher critical penetration energy. The specimen A and C have higher critical penetration energy than B and D because of different stacking sequences. We examined crack length through a penetration test. For the specimen A with 2interfaces, the longest circumferential direction crack length were observed on the first interface from the impact point. For the specimen B 4-interface, the longest circumferential direction crack length were observed on the second interface from the impact point.