• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.6
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• pp.503-508
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• 2009

There are many researches on human effect by electromagnetic equipments and applications. However, most of research and guidelines for limiting human exposure to electromagnetic fields are established by mobile communication of SAR(Specific Absorption Ratio). Therefore we need to study different effects on human body when exposed to high frequency(HF) band equipments, such as human induced current etc. In this paper, we measured human induced current by RFID reader antenna of HF band in the near field and we propose human equivalent antenna which has orthogonal loops to each other. Then, we compared the induced currents on proposed equivalent antenna with human.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.2
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• pp.119-124
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• 2015

The aim of the present study was to assess whether exposure to the combination of an extremely low frequency magnetic field (ELF-MF; 60 Hz, 1 mT or 2 mT) with a stress factor, such as ionizing radiation (IR) or $H_2O_2$, results in genomic instability in non-tumorigenic human lung epithelial L132 cells. To this end, the percentages of G2/M-arrested cells and aneuploid cells were examined. Exposure to 0.5 Gy IR or 0.05 mM $H_2O_2$ for 9 h resulted in the highest levels of aneuploidy; however, no cells were observed in the subG1 phase, which indicated the absence of apoptotic cell death. Exposure to an ELF-MF alone (1 mT or 2 mT) did not affect the percentages of G2/M-arrested cells, aneuploid cells, or the populations of cells in the subG1 phase. Moreover, when cells were exposed to a 1 mT or 2 mT ELF-MF in combination with IR (0.5 Gy) or $H_2O_2$ (0.05 mM), the ELF-MF did not further increase the percentages of G2/M-arrested cells or aneuploid cells. These results suggest that ELF-MFs alone do not induce either G2/M arrest or aneuploidy, even when administered in combination with different stressors.

• Journal of Magnetics
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• v.21 no.3
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• pp.442-449
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• 2016

In this paper, an effective numerical analysis method is proposed for calculating dosimetry of the wireless power transfer system operating low-frequency ranges. The finite-difference time-domain (FDTD) method is widely used to analyze bio-electromagnetic field problems, which require high resolution, such as a heterogeneous whole-body voxel human model. However, applying the standard method in the low-frequency band incurs an inordinate number of time steps. We overcome this problem by proposing a modified finite-difference time-domain method which utilizes a quasi-static approximation with the surface equivalence theorem. The analysis results of the simple model by using proposed method are in good agreement with those from a commercial electromagnetic simulator. A simulation of the induced electric fields in a human head voxel model exposed to a wireless power transmission system provides a realistic example of an application of the proposed method. The simulation results of the realistic human model with the proposed method are verified by comparing it with the conventional FDTD method.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2961-2966
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• 2012

Extremely low frequency electro magnetic fields (EMFs) have been classified as possibly carcinogenic to humans by the International Agency for Research on Cancer. An increased number of chromosomal alterations in peripheral lymphocytes are correlated with elevated incidence of cancer. The aim of the present study was to assess occupationally induced chromosomal damage in EMF workers exposed to low levels of radiation. We used conventional metaphase chromosome aberration (CA) analysis and the micronucleus (MN) assay as biological indicators of non ionizing radiation exposure. In the present study totally 70 subjects were selected including 50 exposed and 20 controls. Informed written consent was obtained from all participants and the study was performed in accordance with the Declaration of Helsinki and the approval of the local ethical committee. A higher degree of CA and MN was observed in exposed subjects compared to controls, the frequency of CA being significantly enhanced with long years of exposure (P<0.05). Moreover increase in CA and MN with age was noted in both exposed subjects and controls, but was significantly greater in the former. The results of this study demonstrated that a significant induction of cytogenetic damage in peripheral lymphocytes of workers occupationally exposed to EMFs in electric transformer and distribution stations. In conclusion, our findings suggest that EMFs possess genotoxic capability, as measured by CA and MN assays; CA analysis appeared more sensitive than other cytogenetic end-points. It can be concluded that chronic occupational exposure to EMFs may lead to an increased risk of genetic damage among electrical workers.

• Science of Emotion and Sensibility
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• v.13 no.4
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• pp.721-732
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• 2010

As increasing of electrical device usage, social concerns about the possible effects of 60Hz electromagnetic fields (EMF) on human health have increased. The number of people with self-attributed electromagnetic hypersensitivity (EHS) who complain of subjective symptoms such as headache, insomnia etc. also increased. However, we don't know whether the EHS results from psychological factor or real perception to the electromagnetic field. In this study, we simultaneously investigated physiological changes(heart rate, respiration rate, heart rate variability, alpha and beta waves in EEG), subjective symptoms and perception accuracy to assess origins of subjective symptoms according to the EMF exposure. Experiment consists of real and sham sessions and 60Hz 12.5uT magnetic field was on(real) or off(sham) to 15 EHS and 16 nonEHS. As the results, EMF exposure did not have any effects on physiological parameters or subjective symptoms for both groups. There was also no evidence that EHS group perceived the EMFs correctly than the control group. Therefore, the origins of subjective symptoms is not the 60Hz magnetic field but psychological factors.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.13 no.2
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• pp.178-178
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• 1999

In recent years, the electromagnetic environments are varied with the increase of power consumption and the spread of household electric appliances. Most of the interests to date have concentrated in the area of human health effects associated with exposure to power frequency electric and magnetic fields, and thus the precise measurement and analysis are required. In this paper, the measurements and analysis of the extremely low frequency(ELF) electric and magnetic fields produced by actual 22.9[kV] distribution lines were performed. The experiments have been carried out by lateral profile, and the theoretical analyses were made by use of FIELDS program for the sate of comparison with the experimental data. Electric and magnetic field intensity were strong under power distribution lines, and were inversely proportional to lateral distance. The profiles of electric and magnetic fields were M and ∩ shapes, respectively, and the measured data were good in agreement with the theoretical results. Both the electric and magnetic field intensity were increased with increasing the measurement height.

• Journal of electromagnetic engineering and science
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• v.13 no.2
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• pp.113-119
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• 2013

We developed a transformed, symmetrical, mushroom-like surface without via holes in cells focused on a 2.4-GHz WLAN band. Each slot in the novel type structure plays a key role in modeling at the desired frequencies. The designed artificial magnetic conductor (AMC) has several advantages, including a small size, a wider bandwidth, a short reflecting distance to the antenna, and easy fabrication because there are no via holes. Overall dimensions of the AMC cell are 21 mm $(Width){\times}21mm$ $(Height){\times}2.6mm$ (Thickness), and the bandwidth is about three times wider (11.7%) compared to that of a conventional AMC (4.0%). For evaluating the performance of the proposed structure, a reflector, which periodically consists of the designed AMC cells, was developed. The antenna with the investigated AMC reflector not only works within a quarter of the wavelength because of the extremely high wave impedance generated by the AMC cells on the surface of the structure but also reduces the specific absorption rate (SAR). Electromagnetic field (EMF) exposure to a human phantom was analyzed by applying the designed reflector to the 2.4-GHz dipole antenna in a tablet PC. The calculated peak SAR averaged over 1 g was 0.125 W/kg when the input power was 1 W and the antenna was located at 20 cm from the human phantom. However, the SAR value was only 0.002 W/kg (i.e., 98.4% blocked) when the designed reflector was inserted in front of the antenna.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.6
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• pp.802-812
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• 1998

Safety related to electric field exposure for the personnel of high voltage power plant and substation is of importance. To analyze the induced current influencing on human body in this paper, we calculate directly capacitance in three dimension which is complex and time consuming, as not to separate the voltage source and the induced object using a effective modeling technique. The proposed algorithm in this paper has been applied to 765 kV high voltage transmission line to evaluate human hazard for the induced current through the case study. As the results, the short circuit current of human body has been identified in the range of 0.3 mA to 6.8 mA. Closing to transmission line, this range of short current can exceed 5 mA that ANSI recommended let-go current. Therefore, it is necessary to countermeasure such as putting on conductive clothing in live-line maintenance of transmission line.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.7
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• pp.2701-2705
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• 2015

Chondrosarcoma, the second most common type of bone malignancy, is characterized by distant metastasis and local invasion. Previous studies have shown that treatment by pulsed electromagnetic field (PEMF) has beneficial effects on various cancer cells. In this study, we investigated the effects of PEMF applied for 3 and 7 days on the matrix metalloproteinase (MMP) levels in chondrosarcoma SW1353 cells stimulated with two different doses of $IL-1{\beta}$. SW1353 cells were treated with (0.5 and 5 ng/ml) $IL-1{\beta}$ and PEMF exposure was applied either 3 or 7 days. MMP-9 and TIMP-1 levels were measured in conditioned media by enzyme-linked immunosorbent assay. The results were relative to protein levels. Statistical analyses were performed using one-way analysis of variance (ANOVA). P<0.05 was considered significant. PEMF treatment significantly decreased MMP-9 protein levels in human chondrosarcoma cells stimulated with 0.5 ng/ml $IL-1{\beta}$ at day 7, whereas it did not show any effect on cells stimulated with 5 ng/ml $IL-1{\beta}$. There was no significant change in TIMP-1 protein levels either by $IL-1{\beta}$ stimulation or by PEMF treatment. The results of this study showed that PEMF treatment suppressed $IL-1{\beta}$-mediated upregulation of MMP-9 protein levels in a dual effect manner. This finding may offer new perspectives in the therapy of bone cancer.

• Journal of Radiation Protection and Research
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• v.33 no.4
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• pp.161-166
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• 2008

In order to determine the effect of extremely low frequency electromagnetic fields (ELF-EMF) on the frequency of micronuclei (MN), aneuploidy and chromosomal rearrangement induced by bleomycin (BLM) in human fibroblast cells, a 60 Hz ELF-EMF of 0.8 mT field strength was applied either alone or with ELM throughout the culture period and a micronucleus-centromere assay was performed. Our results indicate that the frequencies of MN, aneuploidy and chromosomal rearrangement induced by ELM increased in a dose-dependent manner. The exposure of cells to 0.8 mT ELF-EMF followed by ELM exposure for 3 hours led to significant increases in the frequencies of MN and aneuploidy compared to BLM treatment for 3 hours alone (p<0.05), but no significant difference was observed between field exposed and sham exposed control cells. The obtained results suggest that low density ELF-EMF could act as an enhancer of the initiation process of BLM rather than as an initiator of mutagenic effects in human fibroblast.