• 대한치과보철학회지
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• 제41권6호
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• pp.732-746
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• 2003

Statement of problem. Soft lining materials, also referred to as tissue conditioning materials, tissue heating materials, relining materials, soft liners or tissue conditioners, were first introduced to dentistry by a plastic manufacturer in 1959. Since the introduction of the materials to the dental field, their material properties have been continually improved through the effort of many researchers. Soft lining materials have become widely accepted, particularly by prosthodontists, because of their numerous clinical advantages and ease of manipulation. Unfortunately, few reports have been issued upon the topic of increasing the bond strength between the base metal alloy used in cast denture bases and PMMA soft liner modified with 4-META, nor upon the pattern of debonding and material change in wet environment like a intra oral situation. Purpose. The purposes of this study were comparing the bond strength between base metal alloy used for the cast denture bases and PMMA soft liner modified with 4-META, and describing the pattern of debonding and material property change in wet environment like the intraoral situation. Material and Methods. This study consisted of four experiments: 1. The in vitro measurement of shear bond strength of the adhesive soft liner. 2. The in vitro measurement of shear bond strength of the adhesive soft liner after 2 weeks of aging. 3. A comparison of debonding patterns. 4. An evaluation the Relation time of modified soft liner. The soft liner used in this study was commercially available as Coe-soft (GC America.IL.,USA), which is provided in forms of powder and liquid. This is a PMMA soft liner commonly used in dental clinics. The metal primer used in this study was 4-META containing primer packed in Meta fast denture base resin (Sun Medical Co., Osaka, Japan). The specimens were formed in a single lap joint desist which is useful for evaluating the apparent shear bond strength of adhesively bonded metal plate by tensile loading. Using the $20{\times}20mm$ transparent grid, percent area of adhesive soft liner remaining on the shear area was calculated to classify the debonding patterns. To evaluate the change of the initial flow of the modified adhesive soft liner, the gelation time was measured with an oscillating rheometer (Haake RS150W/ TC50, Haake Co., Germany). It was a stress control and parallel plate type with the diameter of 35mm. Conclusion. Within the conditions and limitations of this study, the following conclusions were drawn as follows. 1. There was significant increase of bond strength in the 5% 4-META, 10% 4-META containing groups and in the primer coated groups versus the control group(P<0.05). 2. After 2 weeks of aging, no significant increase in bond strength was found except for the group containing 10% 4-META (P<0.05). 3. The gelation times of the modified soft liner were 9.3 minutes for the 5% 4-META containing liner and 11.5 minutes for the 10% 4-META liner. 4. The debonding patterns of the 4-META containing group after 2 weeks of aging were similar to those of immediaely after preparation, but the debonding pattern of the primer group showed more adhesive failure after 2 weeks of aging.

• 한국조리학회지
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• 제20권3호
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• pp.201-213
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• 2014

본 연구에서는 가열처리방법을 달리하여 기존의 가열처리방법과 열처리용으로 개발된 잠열재 처리와 제작하여 사용하였으며, 닭고기의 가슴살과 다리살의 이화학적 특성과 관능특성을 비교하였다. 일반성분에서 수분은 찌기처리구에서 닭가슴살과 다리살 모두에서 63.6%, 62.1%로 높았으며, 조지방은 삶기처리구에서 1.3%, 8.6%로 가장 낮은 함량을 보였다(p<0.05). 조단백질의 경우, 닭가슴살은 숯불처리구에서 37.9%, 닭다리살은 전기그릴 처리구에서 30.5%로 가장 높게 나타났으며, 조회분 실험결과 닭가슴살은 전기그릴처리구에서 2.4%로 가장 높았으며(p<0.05), 닭다리살은 오븐과 숯불구이처리구에서 1.3%로 가장 높게 나타났다(p<0.05). 가열감량은 닭가슴살과 다리살 모두에서 33.52%, 41.16%로 숯불구이처리구가 오븐구이처리구에 비해 월등히 높았고(p<0.05), 전단력은 전기그릴처리구에서 닭가슴살 $3.53kg/cm^2$, 닭다리살은 $6.80kg/cm^2$으로 가장 높았다. 색도 시험결과 L값은 스팀처리구에서 78.31로 가장 높았고(p<0.05) a 값의 경우, 닭다리살은 오븐구이 처리구에서 10.00으로 가장 높았다(p<0.05). 닭고기 가슴살과 다리살의 관능평가를 9점척도법으로 실시한 결과 전체적인 기호도 항목에서 닭고기 가슴살은 숯불처리구에서 7.25점으로 가장 높았고 삶기와 찌기처리구에서는 6.00점으로 가장 낮은 결과를 보였다(p<0.05). 또한 닭고기 다리살도 숯불구이 처리구에서 7.71점으로 가장 높은 결과를 보였으나 유의적으로는 차이를 보이지 않았다.

• 천문학회지
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• 제32권2호
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• pp.137-147
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• 1999

Recent studies show the importance of understanding three-dimensional magnetic reconnect ion on the solar surface. For this purpose, I consider non-coplanar magnetic reconnection, a simple case of three-dimensional reconnect ion driven by a collision of two straight flux tubes which are not on the same plane initially. The relative angle e between the two tubes characterizes such reconnection, and can be regarded as a measure of magnetic shear. The observable characteristics of non-coplanar reconnection are compared between the two cases of small and large angles. An important feature of the non-coplanar reconnect ion is that magnetic twist can be produced via the re-ordering of field lines. This is a consequence of the conversion of mutual helicity into self helicities by reconnection. It is shown that the principle of energy conservation when combined with the production of magnetic twist puts a low limit on the relative angle between two flux tubes for reconnect ion to occur. I provide several observations supporting the magnetic twist generation by reconnection, and discuss its physical implications for the origin of magnetic twist on the solar surface and the problem of coronal heating.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 추계학술발표대회 논문집
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• pp.99-104
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• 2001

Thermally induced vibration response of solar array is investigated. The solar array model consists of composite thin walled beam and solar blanket, spreader bar. The composite thin walled beam incorporates a number of nonclassical effects of transverse shear, primary and secondary warping, rotary inertia and anisotropy of constituent materials. The solar blanket is a membrane subjected to uniform tension in the z direction. The spreader bar is a rigid member. A coupled thermal structure analysis that includes the effects of structural deformations on heating and temperature gradient is investigated. A stability criterion given in parameters for establishes the conditions for thermal flutter.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제27회 춘계학술대회
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• pp.167-172
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• 1998

An algorithm of Thermal-elastohydrodynamic lubrication analysis for the piston ring is developed. This algorithm contains cavitation boundary condition so it automatically satisfies conservation of mass. 1-D Reynolds equation and 2-D energy equation are solved simultaneously by using Gauss-Jordan method and Newton-Raphson method. Minimum film thickness and friction force are calculated for 1 cycle. There is little difference between the results caculated by isothermal rigid and EHL analysis in entire cycle. In the results of THL, shear heating effect and temperature boundary condition affect the minimum film thickness and friction force prediction. The minimum film thickness and the friction force calculated by THL are lower than those caculated using isothermal assumption.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1966-1971
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• 2003

Matching inviscid and boundary layer methods are developed for hypersonic flow with thick boundray layer. The new equations match all the boundary layer properties with a variation in the inviscid solution near the edge, except for the normal velocity. Computational comparison are performed for incompressible and compressible flows over a flat plate. Results from the present method are compared with Navier-Stokes solutions. The present results are in good agreement with Navier-Stokes solutions. They show that the new technique can provide improved heating rates and skin friction predictions for preliminary design of vehicles where shear layers and entropy layer swallowing are important.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.418-421
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• 2003

Specimens of Ti-10Ta-10Nb have been hot upset forged after heating to either the $\alpha$+$\beta$ and $\beta$-phase field. The variety temperatures (At 650, 700, 750, 800, 85$0^{\circ}C$) and strain rates (At 0.001, 0.01. 0.1, 1, 10 $s^{-1}$ ) were used. On the basis of flow stress data obtained as a function of temperature and strain rate in compression, a processing map for hot working has been developed. At strain rates lower than about 0.1 $s^{-1}$ and almost temperatures, processing efficiency exhibited high, but at 0.001 $s^{-l}$, and temperature 80$0^{\circ}C$, low because the Shear band has occurred. On the basis of the processing map, the optimum processing routes available for hot working of this material are outlined.d.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.399-406
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• 2001

Thermally induced vibration response of composite thin walled beams is investigated. The thin-walled beam model incorporates a number of nonclassical effects of transverse shear, primary and secondary warping, rotary inertia and anisotropy of constituent materials. Thermally induced vibration response characteristics of a composite thin walled beam exhibiting the circumferentially uniform system(CUS) configuration are exploited in connection with the structural bending-torsion coupling resulting from directional properties of fiber reinforced composite materials and from ply stacking sequence. A coupled thermal structure analysis that includes the effects of structural deformations on heating and temperature gradient is investigated.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.1216-1221
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• 2000

Thermally induced vibration response of composite thin walled beams is investigated. The thin-walled beam model incorporates a number of nonclassical effects of transverse shear, primary and secondary warping, 'rotary inertia' and anisotropy of constituent materials. Thermally induced vibration response characteristics of a composite thin walled beam exhibiting the circumferentially uniform system(CUS) configuration are exploited in connection with the structural coupling resulting from directional properties of fiber reinforced composite materials and from ply stacking sequence. A coupled thermal structure analysis that includes the effects of structural deformations on heating and temperature gradient is investigated.

• 한국군사과학기술학회지
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• 제7권3호
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• pp.165-173
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• 2004

Matching inviscid and boundary layer methods are developed for analysis of hypersonic flow with thick boundary layer. The new equations match all the boundary layer properties with a variation in the inviscid solution near the edge, except for the normal velocity. Computational comparison are peformed for incompressible and compressible flows over a flat plate. Results from the present method are compared with Wavier-Stokes solutions. The present results are in good agreement with Wavier-Stokes solutions. They show that the new technique can provide improved predictions of heating rates and skin friction predictions for preliminary design of vehicles where shear layers and entropy layer swallowing are importantfor for preliminary design.