• 한국항공우주학회지
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• 제41권9호
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• pp.755-760
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• 2013

본 논문에서는 우주환경을 고려한 전자파적합성 및 이에 대한 시스템 영향과 시스템 설계 규격을 Multipactor를 사용하여 분석하였다. 또한, 디지털채널증폭기의 시스템 레벨 전자기파 요구사항 분석과 전자기파(EMC) 규격을 초과한 시험결과 분석과 하드웨어 개선방법을 도출하였다. 이 분석과 시험 결과들은 군통신위성의 전자기파 요구사항 및 위성체의 설계 기준으로 제시한다.

• 마이크로전자및패키징학회지
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• 제6권3호
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• pp.51-63
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• 1999

무기 충전제를 고충전시킨 에폭시 수지 조성물이 반도체 패키지의 신뢰성에 미치는 영향을 검토하였다. Ouchiyama 등의 모델로부터 최대충전밀도를 향상시킴으로써 고충전을 달성할 수 있는 방법을 제시할 수 있었으며, 최대충전밀도가 증가함에 따라 에폭시 수지 조성물의 점도가 감소하였고, 흐름성이 개선되었다. 충전제 함량이 증가함에 따라 흡습 특성이 향상되었고 열팽창계수를 낮춤으로써 저응력화를 달성할 수 있었으나, 임계 충전제 함량 이상에서는 금속 리드프레임과의 접착강도가 저하되었다. 따라서 에폭시 수지 조성물의 균형 있는 신뢰 특성을 얻기 위해서는 충전제 함량을 적정하게 선택해야 하며, 충전량을 더욱 높여 고신뢰성을 얻기 위해서는 최적의 충전제 조합을 선정하여야 함을 알 수 있었다.

• 한국전자파학회논문지
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• 제15권6호
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• pp.573-578
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• 2004

전기 기폭장치(EED, electroexplosive device)는 브리지 와이어, 추진제, 리드 핀 및 금속관으로 구성되었고, 기폭신호가 인가되면 브리지와이어의 발열에 의해 추진제를 점화시킨다. 또한 고출력 통신기나 레이더에서 방사되는 전자파에 의해 EED는 예기치 않은 기폭이 발생할 수 있어, EED에 대한 EMC 설계 및 시험관련 군사규격서를 제정하여 적용하고 있다. 본 논문은 항공기에 대한 전기체 EMC 시험평가를 수행할 때, 항공기에 설치 된 EED 대신에 사용할 기폭용 퓨즈의 RF 감도 특성을 기술하였다 RF 기폭수준은 전송선로 이론을 활용하여 예측하였고, 군사규격서에 규정된 DC 감도와 RE 감도를 측정하였다.

• 환경영향평가
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• 제23권1호
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• pp.67-74
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• 2014

The aim of this study was evaluated the effects of total rainfall, rainfall intensity and antecedent dry days and identify the correlation analysis with the EMC removal efficiency, in order to provide an understanding of the operation and maintenance factors of constructed wetland in flood pumping station. This study was conducted total of 20 monitoring in a catchment(326.2 ha) of constructed wetland in Ga-un flood pumping station located at the downstream of the Wang-suk stream. The determined EMC removal efficiencies were $36.04{\pm}9.45%$ for BOD, $38.50{\pm}13.50%$ for $COD_{Mn}$, $34.34{\pm}13.05%$ for TN and $34.22{\pm}14.27%$ for TP, respectively. These results showed that the pollutants concentration and EMC were reduced while passing through the constructed wetland. In the correlation analysis, the highly correlations with EMC removal efficiency of BOD and $COD_{Mn}$ were observed for total rainfall and rainfall intensity (P<0.05). However, the correlations were not found with TN and TP for rainfall variables.

• Archives of Plastic Surgery
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• 제32권5호
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• pp.653-655
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• 2005

Epithelial-myoepithelial carcinoma (EMC) of the salivary gland is a rare tumor that comprises approximately 1% of all salivary gland tumors. It has a distinctive histological appearance comprising ductal structures with an inner epithelial cell component and an outer layer of myoepithelial cells. We report a case of EMC of the parotid gland in a 41- year-old man. He presented left-sided subauricular swelling developed 3-month earlier. Neck CT scans revealed a well-defined mass in the left superficial parotid gland. He underwent superficial parotidectomy and was diagnosed as EMC. He was taken postoperative radiotherapy. There was no evidence of recurrence during a follow-up period of 12 months. A EMC is a low grade malignant tumor which can cause diagnostic confusion during workup and also frequently misdiagnosed as other benign or malignant tumor.

• Journal of the Korean Wood Science and Technology
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• 제26권4호
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• pp.1-5
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• 1998

In this study, it was examined the method to estimate equilibrium moisture content(EMC) at high vapor pressures and high temperatures above $100^{\circ}C$. The material used for the experiment was Sugi(Cryptomeria japonica). EMC was investigated at temperatures ranging from $100^{\circ}C$ to $160^{\circ}C$ and under saturated vapor pressures above 1 atm. The correlation between temperatures and vapor pressures have a good agreement with those observed by thermocouple and pressure gauge in the air state of autoclave, respectively. A sensitivity of quartz spring was 65mm/g. Moisture content(MC)s calculated from the quartz spring elongation by vapor sorption showed a good agreement with MCs by oven-dried method. Using this system, it was found that EMC at high vapor pressures and high temperatures above $100^{\circ}C$ were higher than EMC of wood in 1 atm pressure conditions. With this system, therefore, it was concluded that the EMCs of wood and wood-based materials at high temperatures were able to be evaluated.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 춘계학술대회
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• pp.139-142
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• 2009

전파통신의 급격한 발전에 따라 우리의 생활은 보다 편리하고 풍요로워졌다. 그러나 정밀 전기 전자 장치 및 제어 시스템 등이 경량화, 고속화, 소형화됨에 따라 외부의 EMI(전원장해)와 EFT(과도전압)에 의한 오동작, 인체에 미치는 영향 등의 많은 문제점을 야기 시키고 있다. 따라서 본 논문에서는 이에 대한 대책방법으로 10 MHz ~ 1.5 GHz에서 30 ~ 75 dB 이상의 노이즈 감쇠 특성과 IEC 61000-4-4의 level 4에서 4 kV의 과도전압을 인가시 600 V로 억제시키는 우수한 특성을 가진 대전력용 차단기 내의 EMC 필터를 설계 제작하였다.

• 한국물환경학회지
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• 제34권6호
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• pp.650-660
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• 2018

The objective of this study was to compare the rainfall-runoff characteristics in streams of classified urban and rural watershed using land use and population density. EMC (event mean concentration) of BOD, COD, TP and SS increased significantly in urban and rural watershed, but that of TN remained unchanged. Although there were no significant differences in EMC of BOD, COD, TN, TP depending on the watershed characteristics, EMC of BOD and COD significantly increased in the urban watershed, while EMC of TP increased in the rural watershed. In the urban watershed, the first flush time was faster and the first flush effect was stronger in BOD, COD, and TP. However, the difference between cumulative mass and cumulative volume was found to be less than 0.2 in the rural watershed, indicating a weak first flush effect. The discharged masses of BOD (70 %), COD (64 %), and TP (66 %) in the first flush of runoff were higher in urban watershed, while TN (67 %) was higher in rural watershed. The reproducibility of first flush time and the strength of first flush using CV (coefficient of variation) was found to be more reproducible for first flush time in both watersheds. In rural watershed, the CV value of first flush time for TP out of water quality parameters was lower. Whereas the CV values of first flush time for BOD, COD and TP in urban watersheds were similar.

• 반도체디스플레이기술학회지
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• 제22권1호
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• pp.94-98
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• 2023

In the case of high-speed data transmission on high multilayer boards, signal coherence is a problem, especially due to the via hole, and a solution to improve return loss or insertion loss by applying a back drill to the via hole is being proposed. In this paper, Near-Field Electromagnetic measurements were made on a high multilayer board to determine how the presence or absence of back drill affects signal consistency. For this purpose, we used a signal generator, spectrum analyzer, and EMC scanner on a test board to determine if it is possible to distinguish between areas with and without back drill in the via holes of the stubs on the board. Also, we analyzed the measured value of S11, S21 and EMC etc. for how much it improves the signal attenuation of the stub with back drill. Through this, we knew that less electromagnetic waves are generated the stub via with back drill. At future research, we will analyze how much it improves the signal loss and electromagnetic waves due to the depth of back drill.

• 한국표면공학회지
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• 제32권4호
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• pp.531-537
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• 1999

A copper based leadframe was oxidized in brown-oxide forming solution, then the growth characteristics of brown oxide and the effect of brown-oxide formation on the adhesion strength of leadframe to epoxy molding compound (EMC) were studied by using sandwiched double cantilever beam (SDCB) specimens. The brown oxide is composed of fine acicular CuO, and its thickness increased up to ~150 nm within 2 minutes and saturated. Bare leadframe showed alomost no adhesion to EMC, while once the brown-oxide layer formed on the Surface of leadframe, the adhesion strength increased up to ~80 J/$\m^2$ within 2 minutes. Correlation between oxide thickness, $\delta$ and the adhesion strength in terms of interfacial fracture toughness, $G_{c}$ was linear. Considering the above results, we might conclude that the main adhesion mechanism of brown-oxide treated leadframe to EMC is mechanical interlocking, in which fine acicular CuO plays a major role.e.