• Smart Structures and Systems
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• 제30권4호
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• pp.353-369
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• 2022

In this paper, a new sensor chip with frequency reconstruction range of 2.252 GHz ~ 2.450 GHz is designed and fabricated. On this basis, a self-designed "T-shaped" shell is added to overcome the disadvantage of uneven deformation of the traditional steel shell, and the range of the sensor chip is expanded to 0 kN ~ 96 kN. The liquid metal antenna is used to carry out a step-by-step loading test, and the relationship between the antenna resonance frequency and the pressure load is analyzed. The results show that there is a good linear relationship between the pressure load and the resonant frequency. Therefore, the liquid metal antenna can be regarded as a pressure sensor. The cyclic loading and unloading experiments of the sensor are carried out, and different loading rates are used to explore the influence on the performance of the sensor. The loading and unloading characteristic curves and the influence characteristic curves of loading rate are plotted. The experimental results show that the sensor has no residual deformation during the cycle of loading and unloading. Moreover, the influence of temperature on the performance of the sensor is studied, and the temperature correction formula is derived.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1998년도 가을 학술발표회 논문집
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• pp.431-438
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• 1998

• 대한화학회지
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• 제57권4호
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• pp.525-528
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• 2013

• 사상체질의학회지
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• 제12권1호
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• pp.228-239
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• 2000

1. 연구목적 소음인(少陰人) 성향정기산(星香正氣散)은 "동의수세보원(東醫壽世保元)"의 곽향정기산(藿香正氣散)에 남성(南星)과 목향(木香)의 두 가지 약물이 가미되어 이루어진 처방이다. 이는 소음인이한병(少陰人裏寒病)을 치료하는 처방으로 근래에는 뇌졸중을 비롯한 중추신경계통 질환에 많이 사용되고 있다. 이러한 소음인(少陰人) 성향정기산(星香正氣散)의 용도를 과학기기를 이용하여 기전을 규명하고자 하였다. 2. 연구방법 백서를 urethane으로 마취시키고 소음인(少陰人) 성향정기산(星香正氣散)을 투여한 후 Pressure Transduer와 Laser-Doppler flowmetry를 이용하여 백서의 혈압과 국소뇌혈류량을 측정하였으며 이를 구성약물까지 진행하였다. 또한 소음인(少陰人) 성향정기산(星香正氣散)의 대뇌혈류에 관한 기전 규명을 위하여 propranolol과 methylene blue로 전처치한 후 소음인(少陰人) 성향정기산(星香正氣散)을 투여하여 이를 분석하였다. 3. 결과 및 결론 소음인(少陰人) 성향정기산(星香正氣散)의 투여로 혈압의 유의한 변화는 없었으며, 국소뇌혈류량은 유의하게 증가되었다. 구성약물 중 소엽(蘇葉), 창출(蒼朮), 대복피(大腹皮), 남성(南星)은 국소뇌혈류량을 유의하게 증가시켰으며 목향(木香)은 국소뇌혈류량을 유의하게 감소시켰다. 이 실험으로 소음인(少陰人) 성향정기산(星香正氣散)의 국소뇌혈류량 증가의 기전은 교감신경 ${\beta}$-수용체와 cyclic GMP의 생성효소인 guanylyl cyclase의 작용과 관련이 있는 것으로 생각된다.

• 사상체질의학회지
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• 제12권1호
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• pp.216-227
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• 2000

1. 연구목적 태음인(太陰人) 청심연자탕(淸心蓮子湯)은 "동의수세보원(東醫壽世保元)" 태음인병 24처방 중에 기재된 신정방으로 태음인 간조열증(肝燥熱證)에 응용되는 처방이다. 근래에는 뇌졸중을 비롯한 중추신경계통 질환에 많이 사용되고 있다. 이러한 태음인(太陰人) 청심연자탕(心蓮子湯)의 용도를 과학기기를 이용하여 기전을 규명하고자 하였다. 2. 연구방법 백서를 urethane으로 마취시키고 태음인(太陰人) 청심연자탕(淸心蓮子湯)을 투여한 후 Pressure Transducer와 Laser-Doppler flowmetry를 이용하여 백서의 혈압과 국소뇌혈류량을 측정하였으며 이를 구성약물까지 진행하였다. 또한 태음인(太陰人) 청심연자탕(淸心蓮子湯)의 대뇌혈류에 관한 기전 규명을 위하여 propranolol과 methylene blue로 전처치한 후 태음인(太陰人) 청심연자탕(淸心蓮子湯)을 투여하여 이를 분석하였다. 3. 결과 및 결론 태음인(太陰人) 청심연자탕(淸心蓮子湯)의 투여로 혈압의 유의한 변화는 없었으며, 국소뇌혈류량은 유의하게 증가되었다. 구성약물 중 연자육(蓮子肉), 맥문동(麥門冬), 천문동(天門冬), 원지(遠志), 산조인(酸棗仁), 룡안육(龍眼肉), 나복자, 감국(甘菊)은 국소뇌혈류량을 유의하게 증가시켰다. 이 실험으로 태음인(太陰人) 청심연자탕(淸心蓮子湯)의 국소뇌혈류량 증가의 기전은 교감신경 ${\beta}$-수용체와 cyclic GMP의 생성효소인 guanylyl cyclase의 작용과 관련이 있는 것으로 생각된다.

• 한국태양에너지학회 논문집
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• 제26권4호
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• pp.55-61
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• 2006

Titanium oxide ($TiO_2$) films are deposited on the indium tin oxide (ITO) substrate in an $Ar/O_2$ atmosphere by using reactive RF (Radio Frequency) magnetron sputtering technique, and Electrochromic properties and durability of $TiO_2$ films deposited at different preparation conditions are investigated by using UV-VIS spectrophotometer and cyclic voltammetry Li+ interalation/deintercalation in $TiO_2$ films shows that the electrochromic properties and durability of as-deposited films strongly depend on gas pressure $TiO_2$ films formed in our sputtering conditions are found to remain transparent, irrespective of their Li+ ion contents. The optimum sputtering conditions for film as passive counter electrode in electrochromic devices are working pressure of $1.0\;{\times}\;10^{-2}\;torr$ and oxygen flow raes of $10{\sim}15\;sccm$, respectively.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2002년도 춘계 학술발표회 논문집
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• pp.373-382
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• 2002

In this paper, the characteristic dependencies of LRB(lead rubber bearing) were studied by various prototype tests on LRB for buildings. The characteristics of LRB were dependent on displacements, repeated cycles, frequencies, vertical pressures and temperatures. The prototype test showed that the displacement was the most governing factor influencing on characteristics of LRB. The effective stiffness and equivalent damping of LRB were decreased with large displacement, and increased with high frequency. After the repeated cyclic test with 50 cycles, the effective stiffness and equivalent damping of LRB were reduced by approximately 20% compared with those of the 1$^{st}$ cycle. The effective stiffness was decreased with high vertical pressure, while the equivalent damping was increased. In which, the equivalent damping was more dependent on the vertical pressure than the effective stiffness.s.

• 대한기계학회논문집A
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• 제22권2호
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• pp.321-329
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• 1998

To ensure the structural integrity of the autofrettaged thick-walled cylinder subjected to cyclic internal pressure loading, the fatigue crack propagation life of the cylinder was evaluated. Stress intensity factors of the external cracked cylinder due to internal pressure and autofrettage loadings were calculated using the finite element method. The fatigue crack propagation lives of the cylinder based on the fracture mechanics concepts were predicted and compared to the experimental fatigue lives evaluated from the C-shaped simulation specimens. There were good correlations between the predicted and experimental fatigue lives within a factor of 3 for the single and double grooved C-shaped simulation specimens. Predicted fatigue crack propagation lives of the double grooved cylinders were about 1.5-5 times longer than those of the single grooved cylinders depending on the levels of autofrettage.

• 한국가구학회지
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• 제19권3호
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• pp.172-179
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• 2008

The objective of this study was to investigate the influence of the water repellents' treatment on the water absorptivity and the dimensional stability of Korean red pine wood(Pinus densiflora). The alkylketene dimer(AKD), fluororesin emulsion(Wood-seal, WS), and paraffin wax emulsions(PW25, PW40, and PW1200) were used as water repellents. PW40 and WS were proved as excellent water repellents for pine wood, because the samples treated with these agents showed high contact angles and large reduction in water absorptivities. Also, the dimensional stability(antiswelling efficiency) of pine wood was considerably improved by water repellents treatments, such as PW40 and WS at the pressure of 2MPa. The water repellent treated woods with WS, PW40, and PW1200 at the pressure of 2MPa were relatively stable to the wet-dry cyclic leaching test.

• 한국농공학회논문집
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• 제55권2호
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• pp.87-95
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• 2013

The aim of this study is to examine the behavior of reservoir fill dam with the water level raising by use of the centrifugal model test and the numerical simulation. In this study, LIQCA2D-SF based on the cyclic elasto-plastic constitutive model proposed by Oka et al. (1999) is applied for numerical simulation. In order to investigate the displacements and the pore water pressures in the fill dam due to the water level raising velocity, three model tests in centrifugal field of 50g for fill dams were conducted. A comparison between the test result and the simulation result has provided the influence on the displacement and the pore water pressure of the fill dam with increasing up of the water level.