• 한국항해항만학회지
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• 제30권9호
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• pp.767-772
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• 2006

Generally, a silicone rubber and a chlorinated polyethylene(CPE) have been used as a binder for the development of high-performance composite EM(Electro Magnetic) wave absorbers. In this paper, the EM wave absorption performance of natural lacquer, which is newly proposed as a binder was investigated. The prepared MnZn ferrite EM wave absorbers are mixed with natural lacquer showed excellent EM wave absorption characteristics compared with MnZn ferrite EM wave absorbers which are mixed with the conventional binders. MnZn ferrite EM wave absorbers mixed with natural lacquer were prepared and their absorption ability was also investigated The EM wave absorbers are fabricated in different proportions of MnZn, or NiZn ferrite and natural lacquer, and their reflection coefficients are measured. The permittivity and permeability are calculated by using the measured reflection coefficients. The EM wave absorption abilities are calculated according to different thicknesses of the EM wave absorbers.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.157-161
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• 2006

Generally, a silicone rubber and a chlorinated polyethylene(CPE) have been used as a binder for the development of high-performance composite EM(Electro Magnetic) wave absorbers. In this paper, the EM wave absorption performance of natural lacquer, which is newly proposed as a binder was investigated. The prepared MnZn ferrite EM wave absorbers are mixed with natural lacquer showed excellent EM wave absorption characteristics compared with MnZn ferrite EM wave absorbers which are mixed with the conventional binders. MnZn ferrite EM wave absorbers mixed with natural lacquer were prepared and their absorption ability was also investigated. The EM wave absorbers are fabricated in different proportions of MnZn, or NiZn ferrite and natural lacquer, and their reflection coefficients are measured. The permittivity and permeability are calculated by using the measured reflection coefficients. The EM wave absorption abilities are calculated according to different thicknesses of the EM wave absorbers.

• 한국전자파학회논문지
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• 제17권4호
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• pp.330-334
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• 2006

본 논문에서 Sendust, Mn-Zn, Ni-Zn, Ba, Sr Ferrite를 사용하여 페인트형 흡수체를 제작하였다. 지지재로서는 enamel, epoxy, urethane 페인트들을 사용하여 각각 흡수능을 측정하였다. 그리고 $Al(OH)_3$으로 코팅한 흡수체의 대역폭은 코팅을 하지 않은 것보다 더 넓어지는 것을 알 수 있다. 또 2 mm 두께의 적층형 흡수체는 X-band에서 대략 20 dB의 흡수능을 보여준다.

• Journal of electromagnetic engineering and science
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• 제6권1호
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• pp.71-75
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• 2006

In this study, EM wave absorbers based on Au coated conductive sheets were prepared, and their reflection and transmission coefficients were investigated. An Au coated conductive sheet showed the transmission loss higher than 40 dB in $1{\sim}18$ GHz. Ba ferrite EM wave absorbers with an Au coated conductive sheet showed enhanced EM wave absorption and shield to compare with Ba ferrite EM wave absorbers without conductive sheets. Proposed EM wave absorbers with conductive sheets are useful to protect EM machines from EM interference by strayfields.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.67-68
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• 2005

This thesis is concerned with basic research for development of EM wave absorbers in sheet type for mobile phones. By controlling the sendust ratio, the $Al(OH)_3$ coating, the thickness, the kind of binders, EM wave absorbers were prepared and examined. Centeral frequency shifts toward lower with increasing thickness of the absorber, and absorption ability controlled to adjust Sendust amount. The absorption band of the EM wave absorber coated with $Al(OH)_3$ becomes larger than that of non-coated one. Sendust composite microwave absorbers mixed with CPE were prepared at $70^{\circ}C$ in temperature. The fabricated EM wave absorbers show a reflection coefficient 5.56 dB at 1.8 GHz in thickness of 0.85 mm.

• Journal of electromagnetic engineering and science
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• 제5권4호
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• pp.172-175
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• 2005

Sometimes, it is more convenient to use paint-type and spray-type EM wave absorbers than bulk-type or sheet-type. Thus, in this paper, we prepared paint-type and spry-type EM wave absorbers. The proportion of ferrites to paints, particle size of magnetic material, and kinds of paint should be considered to prepare a superior paint-type EM wave absorber. There is no big gap between spray-type and paint-type in EM wave absorption of EM wave absorbers prepared with same composition.

• 한국항해항만학회지
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• 제30권8호
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• pp.637-642
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• 2006

본 논문에서는 두 종류의 재료에 대한 실험이 진행되었다. 첫째, 센더스트를 이용한 적층형 전파흡수체를 연구하였다. 그 결과, 적층형 센더스트 전파흡수체는 5-Band에서 10dB 대역폭이 확장되었다. 둘째, 적층형 센더스트 전파흡수체에 수산화알루미늄의 혼합 효과를 연구하였다. 그 결과, 수산화알루미늄을 혼합한 적층형 센더스트 전파흡수체는 수산화알루미늄을 혼합하지 않은 적층형 센더스트 전파흡수체와 비교해서 5-Band에서 10dB 대역폭이 확장하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 춘계학술대회 및 창립 30주년 심포지엄(논문집)
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• pp.97-101
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• 2006

본 논문에서는 센더스트를 이용한 적층형 전파흡수체를 제안하였다. 적층형 센더스트 전파흡수체는 S-Band에서 10 dB 대역폭이 확장되었다. 그리고 우리는 적층형 센더스트 전파흡수체에 수산화알루미늄의 혼합 효과를 연구하였다. 그 결과, 수산화알루미늄을 혼합한 적층형 센더스트 전파흡수체는 수산화알루미늄을 혼합하지 않은 적층형 센더스트 전파흡수체와 비교해서 S-Band에서 10 dB 대역폭이 확장하였다.

• Journal of electromagnetic engineering and science
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• 제5권4호
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• pp.161-165
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• 2005

We prepared Mn-Zn ferrite Electromagnetic(EM) wave absorbers. The Mn-Zn ferrite EM wave absorbers were coated with Sr ferrite powders and $Al(OH)_3$ powders. The coated Mn-Zn ferrite EM wave absorbers show improved absorption compared with non-coated Mn-Zn EM wave absorbers.

• Journal of information and communication convergence engineering
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• 제13권1호
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• pp.36-41
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• 2015

With the rapidly increasing and widespread use of electronic and controlling equipment, the control of the electromagnetic (EM) wave environment becomes an important social issue. To solve the electromagnetic compatibility (EMC, both electromagnetic interface and electromagnetic susceptibility) problems, in this paper, we introduce the countermeasure techniques focused on EM wave absorbers for EMC problems in our laboratory at the Korea Maritime and Ocean University. The current technologies related to EM wave absorbers to solve EMC problems will first be described. The prospects of and a design for EM wave absorbers including a smart absorber with a heat radiating function will then be suggested.