• Journal of Radiation Industry
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• v.4 no.1
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• pp.33-38
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• 2010

The MCNP5 neutron, electron, photon Monte Carlo transport program was installed on the KISTI's SUN Tachyon computer using the parallel programming. Electron beam accelerators were modeled and shielding calculations were performed in order to investigate the reduction of computation time in the supercomputer environment. It was observed that a speedup of 40 to 80 of computation time can be obtained using 64 CPUs compared to an IBM PC.

• 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.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.5 no.1
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• pp.31-39
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• 1994

The electromagnetic shielding effectiveness of the various composite materials in the far field region is investigated using the flanged coaxial transmission line sample holder. From these results, we can determine the preference ranking of the various composite materials to use the housing materials of electronic products. These materials have different shielding performances in proportion to the types and volume fractions of metallic powders and metallic fibers included in composite materials. Therefore deter- mination of the optimum volume fraction and the choice of the suitable filler are very important in the design of shielding composites.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.7
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• pp.78-82
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• 2011

In this paper, magnetic field compensation system with an open architecture and can be installed indoors is designed and measured by fabricated. To verify the shielding effectiveness, two rectangular helmholtz coils with 3-axis are fabricated to generate magnetic field and measured magnetic field inside compensation coil for 1~60[Hz], According to measurements, AC shielding effectiveness of compensation system is 96[%] of 1[Hz], 95[%] of 30[Hz] and 90[%] of 60[Hz]. The performance of system therefore can be used as the magnetically shielded room for medical and industrial field.

• 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.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.5 no.4
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• pp.175-179
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• 2012

In this paper, we proposed the modified block structures with enhanced electromagnetic shielding properties for mobie communications and ETC frequency bands. As the result of measurement, this block structure with optimized design has the shielding properties of 30 dB, and can be used for electromagnetic safety and EMI.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.478-482
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• 2021

In this paper, methods for manufacturing shielding concrete by recycling steelmaking slag discarded as industrial waste and measuring the shielding effectiveness of the shielding concrete were studied. By comparing the result of shielding effectiveness measurement of this concrete block with shielding effectiveness measurement of the structure constructed with this concrete, the measurement system for measuring shielding effectiveness of the concrete block was verified. The size of the concrete stru ctu re is 2.9 × 2.9 × 3.4m and the concrete block is 0.3 × 0.3 × 0.2m. The frequ ency band u sed for mesu rement is 600MHz - 2GHz, the types of concrete u sed to measu re the shielding effectiveness are general concrete and concrete containing electric arc furnace oxidizing slag. In the case of the concrete structure, reinforcing rebars are installed at intervals of 15cm for stru ctu ral safety, as the frequ ency increase, the electromagnetic wave properties of rebars gradu ally decreased, there was a slight difference in the measurement results. In conclusion, the measurement result of shielding effectiveness of the concrete block is similar to the result of the concrete structure. It is thought that it can be sufficiently utilized for electromagnetic wave engineering design, and the concrete shielding effectiveness measurement system using standard specimens was verified.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.4 no.3
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• pp.45-53
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• 1993

The shielding effectiveness of materials is determined by measuring the ratio of the incident electromagnetic power to that which passes through the material under test. The measurement system is constructed using several test fixtures, tracking generator, spectrum analyzer, step attenuator, RF switches, and amplifiers, etc.. The automation of measurements is completed using a personal computer. Especially, incident power, reflected power, and transmitted power are measured with only one spectrum analyzer using a dual directional coupler and RF switches. Therefore the system is to be used in design of shielding materials, as well as shielding effectiveness measurements. This system has dynamic range of more than 120 dB in the frequency range of 10 MHz to 1 GHz, and it can be used to measure shielding effectiveness of composite materials.

• Nuclear Engineering and Technology
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• v.20 no.1
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• pp.65-70
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• 1988

A Shielding analysis of the shipping cask designed conceptually, of which shielding material are lead and resin, for containing 4 PWR spent fuel assemblies, has been made with the help of a computer code, ANISN. The shielding materials being used in the cask have been selected and arranged to minimize cask weight while maintaining an overall shielding effectiveness. Radiation source terms have been calculated by means of ORIGIN-2 code under the assumptions of 38,000 MWD/MTU burnup and 3-year cooling time. A calculation of gamma-ray and neutron dose rates on the cask surface and 1m from the surface has been done. It is revealed that the total dose rates under the normal transport and hypothetical accident conditions meet the standards specified.

• Nuclear Engineering and Technology
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• v.51 no.8
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• pp.1998-2004
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• 2019

The Multi-Physics (MP) instrument is one of 20 neutron spectrometers planned in the China Spallation Neutron Source (CSNS). This paper presents a shielding calculation for the MP instrument using Monte Carlo codes MCNPX and FLUKA. First, the neutrons that escape from the CSNS decoupled water moderator and are delivered to the beam line of the MP instrument are calculated to use as the source term of the shielding calculation. Then, to validate the calculation method based on multiple variance reduction techniques, a cross check between MCNPX and FLUKA codes is performed by comparing the calculation results of the dose rate distribution on a simplified beam line model. Finally, a complete geometry model of the MP instrument is set up, and the primary parameters for the shielding design are obtained according to the calculated dose rate map considering different worst-case scenarios.