• 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.

• 전자공학회논문지 IE
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• v.44 no.2
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• pp.21-25
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• 2007

Multilayer transparent electromagnetic wave shielding film with 1 m wide, was fabricated by using roll to roll DC plasma coating with ITO and Ag layer on PET substrate. By optimizing properly the design parameters, such as a processing condition, the surface resistance and the thickness of each layers, the homogeneous film could be obtained. Electromagnetic wave shielding film showed the high shielding effectiveness of 23dB(99.5%) in 2-18 GHz range and the transmittance of 83.1% in 400-700nm.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.3
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• pp.254-263
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• 1997

As the communication and electronic industry develops, it is important to study the electromagnetic shielding effectiveness (SE) of carbon fiber (CF) reinforced thermal plastics (CFRTP) against the electromagnetic (EM) radiation. In this paper the shielding effectiveness of CFRTP was measured experimentally in an electromagnetic shielding room. The resin ma- terials used were PC, PP, PEI, PMMA and PA. Experiments were carried out by using a copper box and a monopole antenna with a spectrum analyzer. From the experimental results it was found that CF was a good candidate as an electromagnetic shielding material. The sheilding effectiveness was found to be increased in the composite as the number of laminated layers of CF was increased. As the minor damage increased, the SE increased due to increasing of the plane density, transmitting thickness and reflected angle of the CF. Other characteristics of the SE depended on the material used for the resin matrix, distance of the antennas and the noise frequency band.

• Journal of the Korea Institute of Building Construction
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• v.21 no.6
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• pp.519-527
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• 2021

In this study, an electromagnetic pulse shielding effect was obtained by applying the arc metal spraying method to the ordinary concrete. For this study, to evaluate the electrical properties in the thickness of the metal sprayed coating, 8 types of metals(Cu, CuAl, CuNi, CuZn, Al, Zn, ZnAl, AlMg) were sprayed as coatings with a thickness of 100, 200 and 500㎛. The electrical conductivity on the surface was measured with a 4-pin probe, and an electromagnetic wave shielding effect test was performed according to KS. Based on the test results, 200 ㎛ was proposed as an optimal metal coating thickness for electromagnetic pulse shielding, and it was thermally sprayed on a 300×300×100mm concrete specimen to analyze the electromagnetic wave shielding performance. However, in the area of adhesion strength, the maximum was 1.11MPa, which was found to be less than 74% of the target performance.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.8 s.185
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• pp.100-107
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• 2006

The objective of this research is to investigate the electromagnetic interference(EMI) shielding characteristics of fiber reinforced composites. We fabricated glass and carbon fiber reinforced composites filled with metal powder and nano carbon black. The measurements of shielding effectiveness(SE) were carried out frequency range 300MHz - 1GHz for commercial purposes such as electric or telecommunication devices. The return loss and loss due to absorption were also measured as a function of frequency in the micro wave(300MHz-1GHz) region. It is observed that the SE of the composites is the frequency dependent, increase with the increases in filler loading. The Mg metal powder filled composite showed higher SE compared to that of carbon black. The Mg metal powder/epoxy composite was shown to exhibit up to 40dB of SE. The results indicates that the composite having higher filler loading can be used for the purpose of EMI shielding as well as for some microwave applications.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.67-76
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• 2020

The purpose of this study was to derive the directionality of technology development of high-power electromagnetic pulse (EMP) shielding concrete and standardization of a shielding performance evaluation method. Because the EMP shielding mechanism of concrete has not been identified clearly, and the verification method for EMP shielding performance has not been standardized, it is difficult to compare the research results between researchers. The development direction of EMP shielding concrete was derived from a consideration of the electromagnetic wave loss mechanism of metal. The standardization direction for verifying the EMP shielding performance of concrete was derived from a consideration of the electrical properties of concrete and the shielding performance evaluation methods of previous studies. As a result, the development of electrically conductive concrete is required, and test methods classified by the electromagnetic wave loss mechanism should be applied. For quality verification, the development of EMP shielding concrete will be feasible and its performance can be evaluated if a test method referencing the generalized shielding evaluation method (MIL-STD, etc.) is applied.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.41-42
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• 2016

In this study, the basic properties of concrete with entrained materials as shielding material for electromagnetic pulse(EMP) within 10kHz~1GHz were investigated. The concretes of moderate strength were prepared with different entrained materials. The shielding effectiveness will be determined according to MIL-STD-188-125-1 at 28 days of concrete curing. The results of physical properties were all satisfied of setting criteria.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.2
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• pp.195-201
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• 2024

The low-temperature deposition of BaNi_(2-x)Co_xFe₁₆O₂₇ thin films with a Ba hexaferrite structure for electromagnetic shielding was studied. The BaNi_(2-x)Co_xFe₁₆O₂₇ thin films produced through the spin spray process were suitable for thin film deposition on a flexible substrate because it crystallized well at low temperature below 90℃. The change in shielding characteristics depending on the Co content of the BaNi_(2-x)Co_xFe₁₆O₂₇ thin film was investigated, and excellent shielding characteristics with S21 of -1 dB were obtained in a wide frequency range of 26~40 GHz when the Co content was 0.4 or more. The purpose of this study is to analyze changes in shielding properties caused by change in Co content in relation to phase changes in BaNi_(2-x)Co_xFe₁₆O₂₇ and obtain basic data for developing excellent flexible electromagnetic wave shielding materials.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.275-276
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• 2014

The electromagnetic wave shielding properties of the carbon coils with polyurethane composites were investigated in the frequency range of 0.25 ~ 1.5 GHz. The shielding effectiveness of the composite having the various-shaped carbon coils were measured and discussed according to the weight percent of the carbon coils in the composites with the thickness of the composites layers. We confirmed that the absorption was the main mechanism to shield the electromagnetic wave interference in the carbon coils composites.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1464-1467
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• 2005

In this research, we developed a system, which can find the location of vehicle when people park their cars in a big parking lot or large area. People can find their cars readily through this simple device and they can save their time and effort. This is the purpose of this research. Performing this, detection of electromagnetic wave's direction is needed and we used shielding effectiveness of electromagnetic waves for the method of it. An absolute coordinate indicates four directions (E, W, S, N) by using an electronic compass module, and it is needed for the localization. The device can check the received count of the electromagnetic waves coming from all other directions through the system, which is installed in the vehicle. The direction recorded the least received count would be the location of the parked vehicles. We can add on the function of this research by using the same frequency of cars alarm goods. Also, it is useful in the huge indoor parking lot.