• Journal of Radiation Protection and Research
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• 제33권4호
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• pp.161-166
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• 2008

극저주파 전자기장의 노출과 여러 암 발생과의 연관성을 구명하기 위해 많은 연구가 이루어지고 있으나 아직도 결론을 내리기에는 논란이 있다. 본 연구에서는 극저주파 전자가장이 소핵, 이수성 및 염색제 재배열과 같은 염색체 손상을 유도하는지 여부와 bleomycin (BLM) 에 악해 유발된 염색체 손상 빈도를 증진시키는지 확인하기 위해 사람 섬유아세포에 BLM과 0.8mT 세기의 극저주파 전자가장을 노출시킨 후 micronucleus - centromere 분석을 수행하였다. BLM의 농도에 따라 소핵, 이수성 및 염색체 재배열의 빈도가 유의하게 증가하 였으며(p<0.05), 0.8 mT 세기의 극저주파 전자기장은 단독으로 사람 섬유아세포에 염색체 손상을 유도하지 않았으나, BLM에 의해 유발된 소핵과 이수성의 빈도를 유의하게 증가시켰다(p<0.05). 따라서 극저주파 전자기장은 단독으로 사람 섬유아세포에 유전독성을 일으키지 않으나 BLM에 의한 소핵과 이수성 빈도를 증폭하는 효과를 나타낸다.

• 한국안전학회지
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• 제8권3호
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• pp.34-43
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• 1993

This paper presents a study on the characteristics and safety criteria for human body in ELF (Extremely Low Frequency : 50-60Hz) electric and magnetic fields. Many researches for ELF electric and magnetic fields, which are developed in the past, are studied and analyzed In this paper. In order to estabilish the safety criteria for human body in the field, the field intensity, induced current and voltage are calculated by the electrostatic field approach which is far simpler than the electromagnetic field one based on Maxwell equation. The method is applied to the 345 KV transmission line system In operation and 765 KV system under consideration. According to the results, the maximum value of field intensity, 6.8627KV/m, is evaluated at the location which is 14m away from transmission line. As the safety criteria value by the abroad researches asserting that the human can detect the Induced current in 6KV/m and above, 5KV/m and 7KV/m are recommended at residence area and nonresidence area, respectively.

• 한국안전학회지
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• 제11권3호
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• pp.89-96
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• 1996

This paper presents a study on the analysis and evaluation for ELF( Extremely Low Frequency) electric and magnetic fields under the transmission line according to the power system states. The power system states are classified into two types, normal state resulting from normal operation and alert state from outages. The current in a system is changed continually owing to the load fluctuations even in a normal operation. To calculate the current of the concerned line in a normal state, the system load level is devided into light, base and heavy load level. In case of contingency, an efficient algorithm based on matrix inversion lemma is developed to figure out the current changes. In order to analyze the variations of ELF field caused by the current fluctuations the electrostatic field approach which is far simpler than the electromagnetic field one based on Maxwell equation is introduced in this paper. The suggested method is applied to the IEEE 14 bus system to demonstrate the usefulness.

• Journal of electromagnetic engineering and science
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• 제12권4호
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• pp.271-279
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• 2012

The effects of extremely low frequency magnetic fields (ELF-MFs) on physiological processes at the cellular level remain unclear despite a number of studies. To investigate the effects of ELF-MFs on gene expression, we exposed human mammary epithelial MCF10A cells to fields of 1 mT magnetic flux density at 60 Hz for 4 and 16 h and measured the transcriptional responses of 24,000 genes using Illumina microarrays. In three independent experiments, we found no statistically significant alteration of expression levels for any of the genes assayed using a cutoff value of 1.2-fold. To confirm this result, we selected six genes with trends suggesting possible expression level changes, although these trends were not statistically significant, and investigated their expression levels further using a semiquantitative reverse-transcription polymerase chain reaction. In three independent experiments, we did not find any alterations in the expression levels of these genes. From these results, we conclude that ELF-MFs do not affect gene expression profiles under our exposure conditions.

• 대한전자공학회논문지SD
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• 제39권6호
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• pp.1-7
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• 2002

비대칭 도파로 마흐젠더(Mach-Zehnder)형 Ti:LiNbO₃ 광변조기를 이용하여 아주 낮은 저주파대 (ELF:Extremely Low Frequency)의 전계계측을 시도하였다. Ti:LiNbO₃ 광변조기를 이용하는 전계센서의 감도는 광변조기의 전극구조에 따라 크게 달라지는 것을 알 수 있었다. 이의 확인을 위한 실험적 연구로서 플레이트(plate)형 프로브안테나를 부착한 광변조기를 제작하여 저주파 전계강도를 측정하였다. 전계강도의 측정은 주파수범위 60㎐ 에서 100㎑ 까지, 전계강도 0.1V/㎝ 에서 60V/㎝ 까지의 범위를 측정하였다. 10㎜×10㎜ 프로브안테나의 경우, 60㎐, 0.1 V/㎝의 피측정전계에서 10㎷의 감도를 얻을 수 있었다. 저주파 전계강도를 측정하기 위해서는 넓은 유효면적을 갖는 플레이트형 프로브안테나가 일반적인 다이폴 안테나보다 유용하다는 것을 확인하였다. 피측정 전자계의 주파수 범위에 따라 안테나의 유효면적을 적당히 조절한다면 더 좋은 센서의 감도를 얻을 수도 있다.

• Biomolecules & Therapeutics
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• 제22권6호
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• pp.570-576
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• 2014

Studies have demonstrated that electromagnetic waves, as the one of the most important physical factors, may alter cognitive and non-cognitive behaviors, depending on the frequency and energy. Moreover, non-ionizing radiation of low energy waves e.g. very low frequency waves could alter this phenomenon via alterations in neurotransmitters and neurohormones. In this study, short, medium, and long-term exposure to the extremely low frequency electromagnetic field (ELF-EMF) (1 and 5 Hz radiation) on behavioral, hormonal, and metabolic changes in male Wistar rats (250 g) were studied. In addition, changes in plasma concentrations for two main stress hormones, noradrenaline and adrenocorticotropic hormone (ACTH) were evaluated. ELF-EMF exposure did not alter body weight, and food and water intake. Plasma glucose level was increased and decreased in the groups which exposed to the 5 and 1Hz wave, respectively. Plasma ACTH concentration increased in both using frequencies, whereas noradrenaline concentration showed overall reduction. At last, numbers of rearing, sniffing, locomotor activity was increased in group receiving 5 Hz wave over the time. In conclusions, these data showed that the effects of 1 and 5 Hz on the hormonal, metabolic and stress-like behaviors may be different. Moreover, the influence of waves on stress system is depending on time of exposure.

• 한국환경보건학회지
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• 제30권3호
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• pp.191-206
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• 2004

The present study investigated the hypothesis that a extremely low frequency magnetic field partially suppresses the synthesis of melatonin in a group of 28 primary schoolchildren living nearby and 60 primary schoolchildren aged 12 years living far away from overhead transmission power lines from December 2003 to April 2004 in Seoul, Korea. The mean personal exposure levels of the primary schoolchildren living nearby overhead transmission power line were 0.37 ${\mu}$T, whereas the value for the primary schoolchildren living away from overhead transmission power line 0.05 mT. From simple analyses, the mean melatonin levels in the primary schoolchildren living nearby were lower than away from overhead transmission power line, but not statistically significant differences in the levels of the melatonin (p=0.2421), whereas the statistically significant differences in the levels of the melatonin related to the distance from residence to power line less and more than 100 m by cut-off point (p=0.0139). In multiple linear regression analyses, distance from residence to power line (p=0.0146) and dietary habit about burned meat (p=0.0170) proved to be significant risk factors in the mean nocturnal melatonin levels in the primary schoolchildren. In conclusion, these results demonstrate that urinary levels of nocturnal melatonin are not altered in primary schoolchildren exposed to extremely low frequency magnetic field(ELF-MF) at overhead transmission power line.

• 스마트미디어저널
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• 제4권1호
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• pp.33-38
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• 2015

분 논문에서는 전위계 센서를 이용한 비접촉식 동작인식거리를 확장하기 위해 1K Hz 이하의 극저주파 EMI를 제거하는 기법과 제스처 동작 시작점 추출을 위한 PLN(Power Line Noice)을 이용하는 기법을 제시한다. 스마트기기 상에 장착된 전위계차 센서 주변에서 발생하는 극저주파대역의 전기장의 세기를 측정하여 효율적인 센서의 배치를 통해 EMI를 제거하는 동시에 60Hz 대역의 PLN 잡음은 오히려 동작 시작점 검출을 위하여 이용하는 기법을 제안한다. 이 후, 접지를 통해 스마트 기기 및 센서의 회로에서 발생하는 전원선 잡음을 제거하고, 스마트 TV와 센서의 사이를 차폐시킴으로써 스마트 기기에서 발생하는 전기적 잡음을 제거한다. 마지막으로 필터기법을 이용하여 남아있는 미세 잡음을 제거한다. 전위계차 센서를 스마트기기의 비접촉식 원격제어에 활용하기 위한 극저주파대역 EMI의 효과적인 제거 기법 및 성능을 분석하였으며, 또한 전위계차 센서의 비접촉식 응용에 난제중 하나인 동작시작점 검출을 위한 효과적인 방법을 제시하여 제스처 인식거리를 실제 응용가능한 3m 이상으로 확장할 수 있음을 보였다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권11호
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• pp.616-621
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• 2002

With biological effects by ELF (Extremely Low Frequency) magnetic field generated from power system, the transient magnetic field from electric appliances is a major issue presently. Because the transient magnetic field induces higher current than the power frequency field inside living bodies, transient magnetic field exposure has been much focused. In this paper, it is shown that transient magnetic field from electric home appliances can be characterized as magnetic dipole moment. In this method, the dipole moment vector is assumed by allowing an uncertainty of 6dB in the estimated field. A parameter M that represents biological interaction was applied also. The proposed method was applied to 7 types of appliances (hair drier, heater, VDT, etc.) and their equivalent magnetic dipole moment and harmonic components were estimated. As the results, the useful data for quantifying magnetic field distribution around electric appliances were obtained.

• Archives of Pharmacal Research
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• 제28권5호
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• pp.587-591
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• 2005

The effect of extremely low frequency (ELF,60Hz) magnetic fields (MFs) on convulsions was investigated in rats. We determined the onset arid duration of convulsions induced by bicuculline alone or by co-exposure to MFs and bicuculline. In addition, we measured the GABA concentrations in the rat brains using HPLC-ECD. MFs strengthened the convulsion induced by bicuculline (0.3, 1, and 3${\mu}g$, I.c.v.), with a shortening of the onset time, but lengthening of the duration time. Co-exposure to MFs and bicuculline decreased the GABA levels in the cortex, hippocampus and hypothalamus, whereas MFs alone reduced the level of GABA only in the hippocampus. These results suggest that the exposure to MFs may modulate bicuculline-induced convulsions due to GABA neurotransmissions in rat brains.