• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.75-78
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• 2000

Since the most of malfunctions in the industrial equipment controlled by processors is occured by the Electrical Fast Transient(EFT), the International Electrotechnical Commission(IEC) prepared the dummy signal to test the immunity level of the equipments. In this paper. we designed a new EMC filter for power line in break-box, which is consist of the feed-through capacitor and ferrite materials with high permeability which was wound or inserted in the second layer of the power cable in order to increase common mode inductance. We have obtained a excellent insertion loss characteristics over wide frequency band from 100 KHz up to 6 GHz. It is expected that the new EMC filter could be effectively used for industrial, MIL, and medical equipments to reduce a malfunctions and be suitable for IEC 61000-4-4.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.3
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• pp.103-111
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• 2003

전자/통신기기에 대한 전자파 장해(EMl/EMS) 문제를 제품개발 기간 내에 완전하게 해결하기란 이론만큼 쉽지 않으며, 전자기적 적합성(EMC)에 대한 지식이 충분하지 못한 회로/기구 설계자들은 전자 파장해 문제를 반복적인 설계 수정 및 디버깅 작업으로 밖에 해결할 수 없는 골치 아픈 Black Magic으로 생각하고 있다. 그러나 분명히 전자기적 간섭(EMI) 문제도 이론 및 해석적인 접근으로 그 해답을 충분히 찾을 수가 있다, 본 고에서는 이러한 PCB Level에서의 전자파장해 문제를 해결하기 위한 체계적인 접근 방법과 오랜 현장 경험에서 나오는 EMC 전문가의 경험적인 지식을 통합한 인공 지능형 EMC 전문가 시스템에 대한 소개와 연구개발 동향 및 극복 과제 등에 대해서 기술하고자 한다.

• Journal of the Microelectronics and Packaging Society
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• v.5 no.2
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• pp.37-48
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• 1998

The popcorn cracking phenomena in plastic IC packages during reflow soldering are investigated by considering the heat transfer and moisture diffusion through the epoxy molding compound(EMC) along with the mechanics of interface delamination. Heat transfer and moisture diffusion through EMC under die pad are analyzed by finite difference method (FDM)during the pre-conditioning and subsequent reflow soldiering pro-cess and the amounts of moisture mass and vapor pressure at delaminated die pad/ EMC interface are calculated as a function of the reflow soldering time. The energy release rate stress intensity factor and phase angle were obtained under various loading conditions which are thermal crack face vapor pressure and mixed loadings. It was shown that thermal loading was the main driving force for the crack propagation for small crack lengths but vapor pressure loading played more significant role as crack grew.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.5 no.3
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• pp.48-58
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• 1994

In this paper, a CLPDA (Crossed Log-Periodic Dipole Antenna) for EMI / EMC Measurement is presented, and is analyzed by Combining the moment method and the transmission line theory. The CLPDA has a broaddband characteristic. It is so important to achieve a impedance matching over op- erating frequency range that Twin-boom method is used at feed point. Here, the current distribution, input admittance, radiation pattern and gain are calculated. In practice CLPDA is fabricated. Calculated result for radiation pattern and gain are very closed to measured result.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.5
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• pp.569-576
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• 2014

There were overwhelming high-frequency electromagnetic noises in 200kW-class hybrid electric vehicle(HEV) although EMC control strategy had been applied to cope with the electromagnetic noises during the development of HEV. This paper investigates the characteristics of the conducted and radiated emission noises, the source and path of noises, and the effects of EMI on the electronics. Finally the design concept of noise control is proposed.

• Journal of Biosystems Engineering
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• v.32 no.6
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• pp.403-407
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• 2007

This study was performed to determine desorption equilibrium moisture contents(EMC) of rapeseed grown in Korea. EMC values were measured by static method using saturated salt solutions at three temperature levels of 30, 40 and $50^{\circ}C$, and eight relative humidity levels in the range from 11.0 to 83.6%. The measured EMC values were fitted to Chung-Pfost, Modified Halsey, Modified Henderson and Modified Oswin models by using nonlinear regression analysis. The results of root mean square errors for four models showed that Halsey and Modified Oswin Models could serve as good models, but the Chung-Pfost and Modified Henderson models could not show reasonably good fitting.

• Proceedings of the Korean Society of Laser Processing Conference
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• 2006.11a
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• pp.103-107
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• 2006

Decapsulation of EMC(Epoxy Molding Compound) in package device is a method used to inspect inside of device by removing plastic molding. So far, chemical etching and mechanical grinding methods have been used widely. Recently, several works using laser have been carried out. This method has advantages with fast process time and precision than conventional methods because of noncontact process. Also, laser process is a clean process because of removing EMC directly without using toxic chemicals. The wavelength of laser used in this study is 355nm. Key parameters of removing EMC are laser power, scan speed, and number of scans of laser. It if confirmed that laser decapsulation is a useful process to inspect inside a device with a small thermal damage to chip surface.

• YAKHAK HOEJI
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• v.43 no.4
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• pp.464-468
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• 1999

In order to find less toxic antiviral agents from basidiomycetes, EA, the water soluble substance, was isolated from the carpophores of Elfvingia applanata (Pers.) Karst. Anti-encephalomyocarditis (EMC) virus activity of EA was examined in Vero cells by plaque reduction assay in vitro. And the combined antiviral effects of EA with interferon (IFN) alpha and gamma were examined on the multiplication of EMC virus. EA exhibited a concentration-dependent reduction in the plaque formation of EMC virus with 50% effective concentration ($EC_{50}$) of 2.12 mg/ml. The results of combination assay were evaluated by the combination index (CI) that was analysed by the multiple drug effect analysis. The combination of EA with IFN alpha showed potent synergism with CI values of 0.40~0.60 for 50%, 70% and 90% effective levels, but that with IFN gamma showed antagonism with CI values of 2.16~2.83.

• Journal of the Semiconductor & Display Technology
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• v.3 no.4
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• pp.33-37
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• 2004

As the high speed and high integration of semiconductor devices and the generation of heat increases resulted in the effective heat dissipation influences on the performance and lifetime of semiconductor devices. The heat resistance or heat spread function of EMC(epoxy molding compound) which protects these devices became one of very important factors in the evaluation of semiconductor chips. Recently, silica, alumina, AlN(aluminum nitride) powders are widely used as the fillers of EMC. The filler loading in encapsulants was high up to about 80 vol%. A high loading of filler was improved low water absorption, low stress, high strength, better flowability and high thermal conductivity. In this study, the thermal properties were investigated through thermal, mechanical and microstructure. Thermophysical properties were investigated by laser flash and differential scanning calorimeter(DSC). For detailed inspection of materials, the samples were examined by SEM.

• Journal of the Korea Safety Management & Science
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• v.11 no.3
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• pp.157-166
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• 2009

In this study, we developed a heuristic algorithm to get better efficiency of clustering than conventional algorithms. Conventional clustering algorithm had lower efficiency of clustering as there were no solid method for selecting initial center of cluster and as they had difficulty in search solution for clustering. EMC(Expanded Moving Center) heuristic algorithm was suggested to clear the problem of low efficiency in clustering. We developed algorithm to select initial center of cluster and search solution systematically in clustering. Experiments of clustering are performed to evaluate performance of EMC heuristic algorithm. Squared-error of EMC heuristic algorithm showed better performance for real case study and improved greatly with increase of cluster number than the other ones.