• Journal of the Korean Wood Science and Technology
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• 제24권1호
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• pp.95-99
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• 1996

The bending and compression strength properties of two types Rhus verniciflua specimens, which made of no heat-treated wood and heat-treated wood for urushiol extraction, were measured. The heat-treated specimens were finger-jointed with either resorcinol-phenol or polyurethane resin adhesives, and the vertical type bending strength property was also measured in these specimens. The results obtained are as follows ; 1. The correlation coefficient between the compression strength and specific gravity in the specimens of no heat-treated and heat-treated wood was high. However there was no difference in compression strength property as affected by heat treatment. 2 The correlation coefficient between the bending strength and specific gravity in the specimens of no heat-treated and heat-treated wood was also high. However, there was no difference in bending strength property as affected by heat treatment. 3 The bending test showed high correlation between modulus of elasticity and modulus of rupture for the specimens made of no heat-treated and heat-treated wood. However, there was no difference in bending strength property between the specimens made of heat-treated and no heat-treated wood. 4. The efficiencies of bending strength test on the finger-jointed specimens of heat-treated wood with resorcinol-phenol and polyurethane resin adhesives were 0.85, 0.81. respectively.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2007년도 춘계학술대회논문집
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• pp.192-198
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• 2007

• 한국초전도ㆍ저온공학회논문지
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• 제12권2호
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• pp.5-8
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• 2010

In this study, the effect of bending strain on the transport property and critical current of lap and butt-jointed (non-laminated) BSCCO tapes has been investigated. The samples were joined using a mechanically controlled jointing procedure. To achieve a uniform thickness at the joint a single point loading contact has been devised. GFRP mandrels with different bending radii which support the sample during bending have been used. $I_c$ have been measured at 77 K and self field. In the case of easy bending test for jointed BSCCO tapes, sudden degradation of $I_c$ is caused by the local strain concentration due to non uniform deformation at the edge parts of the joint. In the case of hard bending test of jointed BSCCO tapes transverse macroscopic crack at specific subsection caused a large $I_c$ degradation. The transport property of jointed BSCCO tapes in each bending mode was discussed with the damage morphology occurred.

• Journal of the Korean Wood Science and Technology
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• 제29권2호
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• pp.118-125
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• 2001

본 연구에서는 소나무의 고부가적 이용을 위한 휨가공 특성을 조사하였다. 먼저 휨가공에 영향을 미치는 수종 특성에 대하여 조사하였다. 다음으로 섬유경사각과 휨가공 특성의 관계에 대하여 조사하였다. 시험편은 섬유경사각 $0^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, $90^{\circ}$와 치수 $10mm(T){\times}20mm(R){\times}350mm(L)$로 제작하였다. 휨가공 전의 고주파조사 시간은 30, 60, 90, 120초로 하였다. 본 연구의 결과는 다음과 같다. 1. 섬유경사각의 크기는 휨가공에 있어 탄성계수와 높은 상관이 있었으며, 섬유경사각이 커질수록 휨가공 성능이 크게 증가하였다. 2 강도적인 측면을 고려할 때, 지나치게 큰 섬유경사각은 강도가 약하기 때문에 휩가공채의 용도에 따라 적당한 섬유경사각의 크기가 조정되어야 할 것으로 판단되었다. 3. 휨가공성은 수종에 따라 현저하게 차이가 있는 것으로 조사되었고 수종특성이 명백히 존재하였다.

• 한국의상디자인학회지
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• 제3권2호
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• pp.63-73
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• 2001

Underwears treated by aroma capsule(UTA) have been known to have many advantages than normal underwears, for example, UTA has antimicrobial and deodorant properties. In this experiment, we examined antimicrobial and deodorant effect of UTA treated by rose and lemon fragrance, Mechanical properties of UTA including surface property, bending property and shear property were also tested. The results are as follows,1. The effects of antibacterial is estimated as 33% and the efficiency of deodouration is about 95 % in UTA. 2. The fragrance of UTA maintained even after 25 times washout. 3. Bending and shear properties were not changed in UTA However it decreased the coefficient of friction of the textures and the smooth surface was detected when the human skin was contacted.

• Journal of the Korean Wood Science and Technology
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• 제30권2호
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• pp.87-94
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• 2002

본 연구는 고주파 가열에 의한 산벚나무, 소태나무, 서어나무, 굴참나무, 박달나무, 고로쇠나무, 피나무, 소나무, 리기다 소나무, 참오동나무의 휨가공성을 평가해 보기 위하여 실시하였다. 본 연구에서 휨가공을 위한 곡율반경은 휨틀의 곡율반경에 의해 4 cm, 6 cm, 10 cm으로 구분하고, 대철의 두께는 0.6 mm와 0.8 mm로 구분하였다. 본 연구결과 소태나무, 서어나무, 박달나무, 고로쇠나무는 모든 곡율반경에서 100% 성공률을 나타내었다. 산벚나무와 굴참나무의 경우 58%와 83%의 성공률을 각각 나타내었다. 피나무와 오동나무의 경우 총 29%와 8%로 매우 불량하게 나타났고, 곡율반경 4 cm에서는 모두 실패로 나타났다. 침엽수재인 소나무와 리기다 소나무는 각각 44%와 56%의 성공률을 나타내었다. 대철의 두께는 휨가공성의 쉽고 어려움보다는 건조시 건조속도에 더 많은 영향을 주는 것으로 나타났다. 건조과정에서 대철두께가 얇을수록 휨가공부재의 건조 속도가 빠른 경향을 나타내었다.

• 한국의상디자인학회지
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• 제12권3호
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• pp.93-103
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• 2010

The results of comparison and analysis of dynamical features according to Jacquard structure are as follows. Regarding elongation(E) value in tensile property, the value in the direction of course was found to be larger in all Jacquard structure, except floating Jacquard, than the direction of wale. It could be found that, as to bending strength(B) in Bending Property, the value of bending strength in the direction of course smaller in all the textile(structure) except floating than the direction of wale, so that the ability of curve formation is excellent. And in case of floating Jacquard, it showed the smallest value in the direction of course and wale, so that it was interpreted as Jacquard having a soft feel. Blister Jacquard showed the highest value in both directions of course and wale, so that it was evaluated as Jacquard having the hardest touch. With regard to shearing character(G) and shearing hysteresis(2HG) in Shearing Property, Jacquard indicated the lowest value, so it was evaluated as the textile(structure) having high drape the transformation of whose fabric is easy. In addition, normal Jacquard, transfer Jacquard, blister Jacquard showed a high value, so that it could be known they are Jacquards having stiff touch. The study implies that normal Jacquard, bird's eye Jacquard, etc., which well stretch in the direction of a course like tubular Jacquard course, is better to make the margin a little shorter than the basic margin, and Jacquard that well stretches in the direction of wale like ladder's back Jacquard and floating Jacquard is better to make the margin longer and the length shorter than the basic margin.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.367-372
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• 2003

Fiber Reinforced Cementitious Composite, DFRCC has strain hardening property with multiple crack in failed of compressive, tensile, bending force, concrete is not so that. But DFRCC could not use to the building element for which has not structural stiffness only has ductile property. DFRCC is used for repair only in recently. In that reason, we considered the concrete of light weight concrete, porous concrete, mortar complex with DFRCC. and DFRCC reinforced by fiber net, steel bar. In this study, results of experiment on complex method of concrete and DFRC were shown as follows; The complex methods of concrete lay on DFRCC, sandwich layer composition were effective for bending force depending on section size each layer, and reinforce DFRCC by fiber net, steel bar was effective method also.

• Journal of Welding and Joining
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• 제32권6호
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• pp.47-55
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• 2014

The purpose of the study is to produce a mechanically improved weld and minimum variation of color through comparing unpulsed and pulsed GTAW (Gas Tungsten Arc Welding) for pure titanium (CP grade7) tube. Pulsed GTAW using 60 A peak current and 20 A background current (1:9) achieved the wider window of welding conditions having part and full penetration without burn-through than the case of unpulsed GTAW. Moreover, the pulsed welding reduced a discoloration on the back bead of the weld and the size of microstructures (basket weave and serrated ${\alpha}$). That is because the pulsed welding has it's a low heat input and severe weld flow induced from electric current variation. Furthermore, the pulsed welding improved the bending property of the welded Ti tube. The enhanced bending property for the pulsed GTAW was due to the insignificant discoloration on the weld surface with maintaining the metal polish.

• 한국의류학회지
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• 제27권8호
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• pp.883-891
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• 2003

In this study, a change of hand of fabrics dyed with persimmon juice was measured using Kawabata Evaluation System. Using various cotton fabrics, linen fabric and silk fabric used frequently for persimmon juice dyeing, we examined the changes of physical properties and hand according to persimmon juice dyeing and washing. The dynamic characteristics of hand were measured tensile, shear, bending, compression, surface properties, thickness and weight. Linearity of load-extention and tensile resilience were increased in all kinds of fabrics after dyeing. Tensile energy decreased in cotton fabric 2(gauze), cotton fabric 3(muslin) and linen fabric. Shear stiffness and hysteresis of shear increased in most of fabrics. Bending rigidity of the bending property and hysteresis of bending, linearity of compression of the compression property, compression energy and compression resilience increased in all kinds of fabrics after dyeing. Thickness and weight increased much in all kinds of fabrics after dyeing. In the primary hand value, stiffness and anti-drape stiffness increased in all kind of fabrics after dyeing. The fullness and softness, crispness, scrooping feeling and flexibility with soft feeling decreased. As the stiffness after persimmons dyeing increased, it was suitable for clothes material of summer.