• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.7
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• pp.834-838
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• 2007

A coupled-defected ground structure(C-DGS) having closely-located DGS cells is proposed for high performance bandstop filter applications. The negative coupling of ground currents between adjacent DGS cells greatly improves the stopband characteristics. We have measured the attenuation slope of 110.8 dB/GHz and -20 dB rejection band from 3.8 GHz to 15.5 GHz. Compared to the double-plane BSF, the proposed BSF improved the sharp cutoff response 7.6 times. We expect the C-DGS be helpful to improve the performance of DGS application circuits and also to extend the possible DGS applications.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.3
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• pp.317-325
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• 2015

In an interference environment, adaptive sidelobe blanking(adaptive SLB: ASB) algorithm effectively cancels the high-duty cycle jammer and blocks the sidelobe signals without the auxiliary antenna. The adaptive SLB for the linearly constrained minimum variance (LCMV) is proposed in this paper. In the proposed scheme, the interference covariance matrix is modified to satisfy the direction constraints of LCMV and the normalized output can be obtained to block sidelobe signals. As the LCMV can be represented as a generalized sidelobe canceller(GSC) form, which is the general framework of various adaptive beamforming(ABF) algorithms, the proposed adaptive SLB can be applied to various ABF methods. The performance of the proposed method is verified through simulation and analysis.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.10a
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• pp.192-195
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• 2003

최근 첨단기술 집약형 자동화 시스템과 정보기술의 발달에 따라 산업은 고도화, 정밀화되고 있다. 특히 안전분야 중 기능성 고분자 재료의 응용 분야로서 carbon black, carbon fiber, graphite, 금속 분말 등의 전도성 충전재를 고분자 matrix에 혼입하여 전도성 복합재료를 성형가공하는 기술이 개발되고 있다. 이를 이용한 복합성형체는 과전류 차단, 회로 보호, 전자파 차폐효과 등의 특성을 이용한 electrical hazard 감소 효과, 제어설비, 자동화 설비, 제조설비 등 각종 산업설비의 정밀제어, 과전류차단 및 외란 방지 등에 다양한 용도로 활용되고 있다.(중략)

• 정보화사회
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• s.184
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• pp.44-47
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• 2007

새해부터는 프로그램저작권 침해행위에 대한 벌칙이 현행 3년 이하의 징역에서 5년 이하의 징역으로 강화된다. 특히, 개인정보보호에 관한 법률이 크게 강화될 예정으로 개인정보를 취급하는 통신사업자의 개인정보 관리.감독 기준이 대폭 강화될 전망이며, 청소년의 유해정보차단을 효율적으로 집행하기 위한 법도 새로 시행될 전망이다. 이밖에도 새해에는 기간통신사업자의 지분인수 시 정보통신부 장관의 인가를 받아야 하며, 무선국 시설자들은 전자파강도를 측정하는 의무가 부여되는 등 많은 부분에서 새로운 제도가 시행될 전망이다. 또, 국세청장이나 지방국세청장도 조세범칙사건의 조사에 필요한 경우에 통신 자료제공을 요청할 수 있도록 법적근거를 마련해 통신매체를 활용한 탈세행위가 새해에는 원천 차단될 전망이다.

• Proceedings of the KIEE Conference
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• 1997.07f
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• pp.2066-2068
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• 1997

네온용 전자식 안정기(EBN)의 출력선간 전자파방해(EMI)로 인한 네온관간의 신호상쇠 현상을 방지하는 회로를 설계하였다. 특히 네온관이 가까이 위치할 때 전자파유도로 인하여 네온발광이 상쇄되는 원인을 방지함으로써 EBN의 성능이 개선되는 결과를 얻었다. 또한 유도전자파를 방지함으로써 인체에 유해한 전자파를 차단하는 효과도 얻었다.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.6
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• pp.711-718
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• 2019

Spectrum analyzer and electromagnetic field meter were used to investigate the EM generation behaviour in different types of home electrical appliances. During microwave oven operation, the EM power measured at a point 30cm apart was measured in the range of 8~11mW/㎡, the strength of the low frequency magnetic field was 60~80mG and the electric field strength was measured at 150~160V/m. For smart phone wireless charging pad, it was measured at an electromagnetic power of 0.4mW/㎡, an electric field of 160 V/m and a magnetic field of 1mG at a point 10cm away. For microwave oven and wireless charging pad, if used within 10cm, the size of the electric field has been measured at a large value that exceeds the human body protection standard and may be hazardous to humans. On the other hand, home appliances such as TVs, hairdryers and refrigerators all showed very low levels of electromagnetic waves, electric fields and magnetic fields, with no harmful effects seen. For electromagnetic shielding, the metal Cu fabric and metal foil had a high level of EM shielding, while polymer films had a low EM shielding characteristic.

• The Journal of the Korea Contents Association
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• v.11 no.9
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• pp.129-136
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• 2011

In this paper, the shielding material for the product design of various electrical appliances is suggested by more environmentally materials like as the lacquer and the charcoal. The suggested shielding material has the shielding effectiveness of 97.2%, 98.7%, and 96.3% at 900 MHz, 1.8 GHz, and 2.45 GHz, respectively. In the microwave oven and the cell phone, the metal or metal-coated plastic are used for the shielding of strong electromagnetic wave. However, by using more environmentally materials like as the lacquer and the charcoal, the products can be manufactured more light weighting, more heat-resisting, more abrasion resisting, and more corrosion resisting. Also, the products design can be varied more mellow and more friendly.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.3
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• pp.355-360
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• 2012

In this paper, an stepped-impedance low pass filter(SI-LPF) of triangular-patch type is proposed. A SI-LPF designed according to the standard SI-LPF design procedure is folded as a right angled triangle. The figure of merits of this structure are the adjustabilities of the cut off frequency, the stopband and the attenuation pole frequency of the proposed LPF by varying the resultant slots after folding the SI-LPF compactly for miniaturization. The size of the fabricated LPF is $13.75mm{\times}6.875mm$, which is 24.4 % reduced one compared to that of the conventional SI-LPF. The measured results of the LPF show return loss of less than -10 dB at passband, insertion loss of less than -10 dB at stopband and wide stopband from 3.5 GHz to 10 GHz (about $3f_c$).

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.4
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• pp.498-505
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• 1999

The ferrite device that has nonreciprocal characteristics has been used as various microwave components. In this paper, the spectral-domain method was used to analyze the characteristics of structure(strip line on multilayer structure with ferrite material) for which no paper has been published yet. It is assumed that an external dc magnetic field is applied perpendicular to the ground conductor. The propagation constant is calculated for each parameter and frequency. Also we considered convergence by increasing the number of basis functions and verified the numerical analysis results. From the results, we could confirm that as the thicknesses of YIG is increased, the cutoff region is widened and the propagation constant is decreased at the frequency of upper cutoff region. For a larger applied dc magnetic field, the frequency of cutoff region is found to be increased. Also the simulation results for strip line show that the cutoff region is widened and the propagation constant is larger than that of microstrip line.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.2
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• pp.44-52
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• 2002

본 논문에서는 RF와 마이크로파 응용을 위한 MEMS 수동 소자에 대한 내용이다. 이 수동 소자들을 만들기 위해서 개발된 3타원 MEMS공정은 기존의 실리콘 공정과 완전한 호환성을 가지고 한 칩으로 집적화 시킬 수 있는 공정이다. 이 3차원 MEMS 공정은 기존 실리콘 긍정이 가지고 있는 한계를 극복하기 위한 방법으로써 개발되었다. 개발된 공정을 이용하여 실리콘 공정에서 구현할 수 없었던 좋은 성능의 인덕터, 트랜스포머 및 전송선을 RF와 마이크로파 응용을 위해서 구현하였다. 저 전압, 높은 차단율을 위한 push-pull 개념을 도입한 MEMS 스위치를 구현하였다. 또한 높은 Q를 갖는 MEMS 인덕터를 최초로 CMOS 칩과 집적화에 성공하여 600kHz 옵셋 주파수에서 -122 dBc/Hz의 특성을 갖는 2.6 GHz 전압 제어 발진기를 제작하였다.