• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.3
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• pp.234-243
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• 2023

The electromagnetic pulse(EMP) is a general term for high-output electromagnetic waves, and is classified into EMP generated from nuclear weapons, non-nuclear EMP, and EMP generated by natural phenomena. Electromagnetic pulses are means that can cause fatal damage to all electronic devices with electromagnetic elements, such as communication devices, mobile phones, computers, TVs, and means of transportation. In this study, the electromagnetic pulse(EMP) shielding effectiveness evaluation of paints according to the type and amount of carbon material was conducted to develop EMP shielding inorganic paint using carbon materials. In order to analyze the improvement of compatibility and dispersibility between materials, experiments were conducted two times with about 27 types of mixture proportions, and the electromagnetic pulse shielding effectiveness was evaluated by the electrical resistance measurement method. As a result of applying the EMP shielding paint developed through this study to shielding concrete, it was confirmed that the shielding performance was improved from about 25 dB to a maximum of 40 dB.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.20-21
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• 2016

In this study, the shielding properties of concrete with conductive materials as shielding material for electromagne- tic pulse(EMP) within 10kHz~18GHz were investigated. The shielding effectiveness of specimens were compared with different entrained materials. The shielding effectiveness were determined according to MIL-STD-188-125-1, IEEE-STD-299 at 28 days of concrete curing. The results of shielding effectiveness did not meet the criteria(80dB) severely.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.12
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• pp.1011-1014
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• 2017

Additional metal shielding is installed in the water pipes used in septic tanks to protect against damage from electromagnetic pulse (EMP) events. This shielding prevents EMP damage, but impurities present in water cannot pass through the shielding structure. Thus, the original function of the water pipes is lost as the pipes are blocked, and an additional maintenance workforce is needed to manage this blockage. To solve this problem, we propose a water pipe without an additional shielding structure; the proposed pipe was designed with consideration of the attenuation characteristics of water. The immersed depth was varied from 400 mm to 800 mm, while the diameter of the pipe was fixed at 100 mm. The shielding effectiveness increased from 70 dB to 100 dB around 2 GHz. Through the verification process, we propose an effective design guideline that can maintain the function of the water pipe and provide protection from EMP damages without additional shielding structure.

• 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.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.5
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• pp.548-558
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• 2014

EMP(Electromagnetic Pulse) protection facility was evaluated according to standard of shielding effectiveness. To comply with the standard, transmitting antenna was placed on outside of protection facility and receiving antenna was placed on inside of protection facility. However, measurement is impossible that place does not have enough space between protection facility and external concrete structure. In this paper, we performed a various of tests that put transmitting antenna inside the EMP protection facility in order to find out test method for measuring the shielding effectiveness of electromagnetic wave. Transmitting antenna was placed on inside of the EMP protection facility for measuring the shielding effectiveness to compare and analyze the impact of the position regarding to the transmitting and receiving antenna. As a result of test, in case that transmitting antenna was placed on inside of the EMP protection facility, it was found that test frequency range 10 kHz~1 GHz were occurred overall average difference of ${\pm}4$ dB level.

• Journal of the Korea Institute of Building Construction
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• v.19 no.3
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• pp.209-217
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• 2019

EMP (Electromagnetic Pulse) usually means High Power Electromagnetic Wave (HPEM). In the case of the shielding plate against the EMP, there is a possibility of deterioration of the electromagnetic wave shielding performance due to the skill of the constructor, bad construction, deformation of the shielding plate at the connection portion (joint portion). The inefficient use of space due to the separation distance is also pointed out as a problem. Therefore, this study aims to derive the optimum electromagnetic shielding condition by applying ATMSM to concrete as a part of securing electromagnetic wave shielding performance with reflection loss against concrete wall. Experimental parameters included concrete wall thickness and application of Zn-Al ATMSM. For the concrete wall, the wall thickness was 100 to 300mm, which is generally applied, and experimental parameters were set for the application of Zn-Al metal spraying method to evaluate electromagnetic shielding performance. Experimental results showed that as the thickness increases, the electromagnetic shielding performance increases due to the increase of absorption loss. In addition, after the application of Zn-Al ATMSM, the average shielding performance increased by 56.68 dB on average, which is considered to be increased by the reflection loss of the ATMSM. In addition, it is considered that the shielding performance will be better than that when the conductive mixed material and the ATMSM are simultaneously 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.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.18-19
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• 2020

The ElectroMagnetic Pulse (EMP) destroys social infrastructure at once and causes social chaos. However, currently major infrastructures are constructed of concrete that does not have electromagnetic shielding performance. In this study, using the arc metal spraying method is used to evaluate the shielding performance and construction performance of concrete. The electro-magnetic shielding effect is measured by fabricating a shielding room with reference to MIL-STD-188-125, and the construction performance is evaluated by measuring the adhesion strength of thin metal sprayed film-concrete. As a result of the study, when the metal spraying method is applied, the shielding effect is higher than that of the special electro-magnetic shielding concrete, and it is considered to be more economical than the existing metal plate (3~5 mm).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.7
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• pp.366-372
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• 2017

The objective of this study was to characterize Waveguide-Blow-Cutoff (WBC) array for Electromagnetic Pulse (EMP) shield in air duct or water pipe, the typical pathway of pulse in indoor space with critical electronic device. A numerical investigation with three different WBC designs (circular, rectangular, and hexagonal or honeycomb) was conducted to satisfy recommended shielding effectiveness (SE) levels from 80 dB to 140 dB. Pressure drop between upstream and downstream of EMP shields based on WBC arrays was also investigated to understand air flow feature in air duct of HVAC system. Results showed that honeycomb geometry outperformed other shapes in terms of reducing the depth of EMP shield, thus providing better air flow in duct path with lower local loss coefficient in HVAC system under SE requirements.

• Fire Science and Engineering
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• v.30 no.4
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• pp.94-102
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• 2016

When establishing shielding facilities for EMP protection, WBC effect is used to protect fire pipes and honeycomb cells are inserted into the fire pipes to improve the shielding effectiveness. At this point, the smaller unit cell of honeycombs becomes, the more likely it interrupts the flow of water, which ends up clogging the fire pipes with sediment. To prevent this phenomenon, I would suggest a design method due to the pilarization loss of water molecules that contributes to increasing the size of honeycomb cells and remaining thin-walled sufficient for required shielding effectiveness.