• 한국광학회지
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• 제10권3호
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• pp.188-194
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• 1999

Mitsunobu 반응을 이용하여 전기광학계수 $\gamma_{33}$크고 열적 .시간적으로 안정적인 폴리이미드(polyimide)계고분자 용액인 PI-SOT(폴리이미드계 4-[N,N-bis(hydroxyethyl)amino­4'­($\beta$­cyano-$\beta$­methylsulfonyl)vinyl]azobenzene)고분자를 합성하였다. C.C. Teng의 단순반사법을 이용하여 코로나 폴링으로 극성 배향시킨 PI-SOT 박막의 전기광학계수 $\gamma_{33}$의 열안정성 및 시간안정성을 파장 632.8 nm와 852nm에서 측정하였다. 그 결과 상온에서 전기광학계수$\gamma_{33}$은 파장 632.8nm서 25.12 pm/V이고, 852 nmsns 5.40pm/V였다. 이 값들은 상온에서 60일 이상 장기간 안정적으로 유지되었으며, $100^{\circ}C$의 고온에서도 10시간내에서 6% 이내로 안정된 값을 유지하였다.

• 대한한방부인과학회지
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• 제32권4호
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• pp.25-38
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• 2019

Objectives: The purpose of this study is to analysis differences of heart rate variability (HRV), body composition, digital infrared thermal imaging (DITI), and electro pulse graph by whether there are some causes of dysmenorrhea or not. Methods: We studied 89 patients who took at least one test among HRV, Body composition, DITI, and electro pulse graph visiting Kyung Hee University Hospital at Gangdong from March 1, 2014 to May 7, 2019. Results: There were statistically significant differences in Low frequency (LF), LF norm and High frequency norm (HF norm) of HRV between primary dysmenorrhea patients and secondary dysmenorrhea patients. There were statistically significant differences in Body Mass Index (BMI) and body fat percentage of Body composition between two groups. But both BMI were included in normal range. There were no statistically significant difference in DITI results. And there was significant difference of Estimated circulation resistance (ECR) between two groups. Conclusions: The results suggest that hormone imbalance of secondary dysmenorrhea patients can affect HRV results. And because of high ECR, phlegm pathology can be more considered in secondary dysmenorrhea patients. Further study should be conducted to confirm the results of body composition and DITI differences.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1992년도 특별강연 및 추계학술발표 개요집
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• pp.213-214
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• 1992

No Abstract, See Full Text

• Bulletin of the Korean Chemical Society
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• 제26권5호
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• pp.841-844
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• 2005

• Bulletin of the Korean Chemical Society
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• 제28권2호
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• pp.329-332
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• 2007

• 항공우주시스템공학회지
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• 제16권3호
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• pp.84-92
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• 2022

전기-정유압식 작동기(EHA)는 독립적으로 유동력원을 운용함에 따라, 복잡한 유압 배관을 제거할 수 있어 누유 및 중량 최소화, 안전성 향상의 장점이 있어 최근 항공기용 비행제어 분야에서 사용되고 있다. 이러한 EHA를 탑재하는 항공기의 경우, 기존 중앙 유압시스템을 탑재한 항공기에 비해 제한된 냉각원에 따른 EHA의 열관리 이슈가 대두된다. 이러한 열관리 이슈의 해결을 위해서는, EHA의 열특성을 예측할 수 있는 열해석 모델이 필요하다. 본 연구에서는 유압펌프 및 전기모터로 구성되는 EHA 유압동력모듈의 내부 회전체를 고압 하에서 고속으로 회전이 가능하도록, 유압동력모듈 내부에 유체 순환 회로를 적용하였다. 적합한 열해석 모델을 구축하고, 유냉식 또는 비유냉식 유압동력모듈 적용에 따른 해석 결과의 비교 및 검토를 통해 EHA의 열특성 영향성을 확인하고자 하였다.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2006년도 ISMP 2006
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• pp.67-73
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• 2006

A system in package (SiP) generally contains a variety of systems such as analog, digital, optical and micro-electro-mechanical systems, integrated in a system-level package connected through a substrate. However, there are many electrical and mechanical reliability issues including the reliability issue for embedded structures. A mismatch of thermal coefficients of expansion among packaging materials and devices can lead to warping or delamination in the package. In this study, the effect of material properties of underfill, such as Young's modulus and CTE, are investigated through FEM simulation. Experimental investigation on the warpage of the package is also carried out to verify the simulation results. The results show that the reliability of the system in package is closely related to the material properties of underfill. The results of this study provide a good guidance for the material selection when designing the system in package.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.253-253
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• 2008

Recently, high performance microelectronic devices are designed in multi-layer structure in order to make dense wiring of metal conductors in compact size. For making dense wiring of metal conductors, we investigated CTE and peel strength of dielectric materials for next generation PCB. It is an object of this research to develop an epoxy resin composition for an interlayer insulating material exhibiting low CTE and high peel strengnth and making an insulating layer thinner.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.229-234
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• 2002

Under the hostile influence of the extreme space environmental conditions due to the deep space and direct solar flux, the thermal control in space applications is especially of major importance. There are tight temperature range restrictions for electro-optical elements while on the other hand there are low power consumption requirements due to the limited energy sources on the spacecraft. So, we usually have strong requirement of thermal and power control module in space applications. In this paper, the design concept of a thermal and power control module in the MSC(Multi-Spectral Camera) system which will be a payload on KOMPSATII is described in terms of H/W & S/W. This thermal and power control module, called THTM(Thermal and Telemetry Module) in MSC, resides inside the PMU(Payload Management Unit) which is responsible for the proper management of the MSC payload for controlling and monitoring the temperature insides the EOS(Electro-Optic System) and gathering all the analog telemetry from all the MSC sub-units, etc. Particularly, the designed heater controller has the special mode of "duty cycle" in addition to normal closed loop control mode as usual. THTM controls heaters in open loop according to on/off set time designed through analysis in duty cycle mode in case of all thermistor failure whereas it controls heaters by comparing the thermistor value to temperature based on closed loop in normal mode. And a designed THTM provides a checking and protection method against the failure in thermal control command using the test pulse in command itself.

• 센서학회지
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• 제18권6호
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• pp.441-448
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• 2009

Magnesia partially stabilized zirconia(Mg-PSZ) solid electrolytes for an improvement of thermal shock resistance, which is suitable for the measurement of oxygen activity in a molten steel, were prepared by post-thermal aging treatment. The steelmaking oxygen sensor elements were formed by an injection molding method, sintered at $1650^{\circ}C$, and then thermal aged ranged from 1250 to $1400^{\circ}C$. Sintered density and porosity were decreased as increasing the magnesia content in a zirconia-magnesia solid solution. Fractions of cubic phase to the synthesized Mg-PSZ solid electrolytes were ranged from 13.13 to 79.54.% after post-thermal aging treatment. Very dense microstructure without voids in the grains was obtained by the post-thermal aging process. Fine tetragonal phase crystallites precipitated on the cubic surface during post-thermal aging up to $1300^{\circ}C$ improve a thermal shock resistance and reappearance of electro motive force(EMF) curve.