• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.7
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• pp.1265-1271
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• 2010

Power cable of an AC arc welder can surround a body of worker at the moment of welding. Applying the boundary element method, we calculated current densities induced in organs inside a worker to study the magnetic field reduction characteristics of shielding wear materials. We knew shielding wear with high permeability materials lowers current density more than high conductivity materials. We also found current density was lowest when high permeability materials were inside high conductivity materials in double layer shielding wear.

• Fashion & Textile Research Journal
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• v.21 no.5
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• pp.618-626
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• 2019

This study conducted basic studies to develop electromagnetic wave shielding maternity wear. We investigated electromagnetic wave shielding fabrics and products as well as surveyed actual wearing states for pregnant women aged 35 to 44 and women who gave birth within the past one year. Available electromagnetic wave blocking products for pregnant women were blankets, aprons, maternity belts, and underwear. These only cover the abdomen and it was hard to find out electromagnetic waves shielding maternity wear, which can enhance functionality and complement the body shapes of pregnant women. The aged mother responded pregnancy delay was mostly attributable to late marriage, career, financial difficulty and health problems. Major health threats to babies were high stress levels during pregnancy, followed by electromagnetic waves from electronic devices. They prioritized physical activity, design, functionality and safety when wearing maternity wear. When purchasing maternity wear, they emphasized design, price, materials and size. The most preferred clothing was one-piece dress; consequently, only 11.1% of them were satisfied with the quality of maternity wear with complaints mostly about design and price. A total of 63% of respondents tried to protect themselves from electromagnetic waves. Most aged mothers showed a positive intention on purchasing electromagnetic waves blocking maternity wear for babies with concerns dealing with safety of materials, prices, ease of laundry, and body complementing design.

• Proceedings of the KIEE Conference
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• 2008.10a
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• pp.73-74
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• 2008

This paper analyses current densities induced inside a worker using AC arc welder when he wear a protective with double shielding cloth. Applying the boundary element method, we calculate current densities induced in organs inside a worker in case he was located at 1[cm] far from a power cable of AC arc welder. As results of study, we fined aa protective cloth, which has high permeability in inner layer and high conductivity in outer layer, can give a higher shielding efficiency.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.9
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• pp.1632-1637
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• 2007

This paper analyses current densities induced inside human body of lineman for 765kV transmission line when he wears a protective cloth or not. Applying the boundary element method, we calculate current densities induced in organs inside a worker in case he was located at 15[cm], 30[cm], 50[cm], and 100[cm] far from a prefabricated jumper. As results of study, we find a maximum current density induced in all organs may be higher than $10[mA/m^2]$ if he does not wear protective clothes. We also know high permeability materials can lower current density more than high conductivity materials.

• Journal of Welding and Joining
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• v.18 no.6
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• pp.68-73
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• 2000

In case of overalyered wrapping roll, beadmark shape appear at wrapping roll surface due to irregular wear between weld bead. Irregular wear of this is caused by difference of hardness between weld bead. This study aims at investigating which matrix is good for removing of beadmark at wrapping roll surface. So, we make specimen with martensitic matrix and austenitic matrix. The overlayered alloys were deposited 4 times on a SS41 steel plate using self-shielding flux cored arc welding method. Difference of hardness between weld bead of specimen with matrix of martensite was higher than specimen with matrix of austenite both as-welded and after heat treatment. Therefore, austenitic matrix is between than martensitic matrix for removing of beadmark of wrapping roll surface.

• Nuclear Engineering and Technology
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• v.52 no.3
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• pp.647-653
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• 2020

Stainless steel is used commonly in nuclear applications for shielding radiation, so in this study, three different types of new stainless steel samples were designed and developed. New stainless steel compound ratios were determined by using Monte Carlo Simulation program Geant 4 code. In the sample production, iron (Fe), nickel (Ni), chromium (Cr), silicium (Si), sulphur (S), carbon (C), molybdenum (Mo), manganese (Mn), wolfram (W), rhenium (Re), titanium (Ti) and vanadium (V), powder materials were used with powder metallurgy method. Total macroscopic cross sections, mean free path and transmission number were calculated for the fast neutron radiation shielding by using (Geant 4) code. In addition to neutron shielding, the gamma absorption parameters such as mass attenuation coefficients (MACs) and half value layer (HVL) were calculated using Win-XCOM software. Sulfuric acid abrasion and compressive strength tests were carried out and all samples showed good resistance to acid wear and pressure force. The neutron equivalent dose was measured using an average 4.5 MeV energy fast neutron source. Results were compared to 316LN type stainless steel, which commonly used in shielding radiation. New stainless steel samples were found to absorb neutron better than 316LN stainless steel at both low and high temperatures.

• Journal of Welding and Joining
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• v.16 no.2
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• pp.73-83
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• 1998

This study investigated the relationships between the microstructure and the wear resistance of hardfaced iron/chromium alloys to examine the low stress abrasive wear mechanism. The effects of volume fraction of reinforcing phases(chromium carbide and eutectic phase) were studied. The alloys were deposited once or twice on a mild steel plate using a self-shielding flux cored arc welding process. The low stress abrasion resistance of he alloys against dry sands was measured by the Dry Sand/Ruber Wheel Abrasion Tester (RWAT). The wear resistance of hypoeutectic alloys, below 0.36 volume fraction of chromium-carbide phase (VFC), behaved as Equal Pressure Mode (EPM) for the inverse rule of mixture whereas the wear resistance of hypereutectic alloys, above 0.36 VFC, represented Equal Wear Mode (EWM) for the linear rule of mixture.

• Journal of Welding and Joining
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• v.16 no.1
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• pp.114-124
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• 1998

The effect of matrix phase (austenite, pearlite, martensite) on the low stress abrasion resistance in the chromium-carbide-type high Cr white iorn hardfacing weld deposites has been investigated. In order to examine matrix phase, a series of alloys with different matrix phase by changing the ratio of Cr/C system by heat treatment were employed. The alloys were deposited twice on a mild steel plate using self-shielding flux cored arc welding process. The low stress abrasion resistance of the alloys against sands was measured by the Dry Sand/Rubber Wheel Abrasion Test(RWAT). Even though formation of pearlite phase in the matrix showed higher hardness than that of austenite, there was no observable difference in wear resistance between the pearlite and austenite phase for the same amount of chromium-carbide in the matrix. On the other hand, the formation of martensitic phase,, from heat treated austenitic alloys (high content of Cr), enhanced wear resistance due to its fine secondary precipitates.

• Journal of Welding and Joining
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• v.16 no.1
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• pp.125-133
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• 1998

The effect of volume fraction of Cr carbide phase (Cr CVF) on the low stress abrasion resistance in the chromium-carbide-type high Cr white iron hardfacing weld deposits has been investigated. In order to examine Cr CVF, a series of alloys with varying Cr CVF by changing chromium and carbon contents and the ratio of Cr/C were employed. The alloys were deposited once or twice on a mild steel plate using the self-shielding flux cored arc welding process. The low stress abrasion resistance of the alloys against sands was measured by the Dry Sand/Rubber Wheel Abrasion Test (RWAT). It was shown that hardness and abrasion resistance increased with increasing Cr CVF within the whole test range (Cr CVF : 0.23-0.64). Both primary Cr carbide and eutectic Cr carbide were particularly effective in resisting wear due to their high hardness.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1465_1466
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• 2009

Power cable of an AC arc welder can surround a body of worker at the moment of welding. Applying the boundary element method, we calculated current densities induced in organs inside a worker in case he weared a multi-layer shielding cloth. We know these were lowest when high permeability materials such as silicon and permalloy were applied to the interior of a suit and high conductivity materials such as copper were to the exterior.