• 월간산업보건
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• 통권368호
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• pp.16-16
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• 2018

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.1196-1199
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• 2002

The low phase noise frequency source to be used for measurements and so on realizes by oscillator having highly output signal power against output noise power. SAW devices can be used by high power than BAW devices. So we examine on configuration of SAW oscillator circuits with the power gain. In this paper we shall discuss a configuration of oscillator circuit to obtain an extremely low phase noise and an oscillator operating at a non-reactive frequency of SAW resonator.

• Journal of Radiation Protection and Research
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• 제20권3호
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• pp.187-200
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• 1995

본 연구는 극저주파대 전자기장(ELF)의 잠재적 건강위해를 문헌을 통해 고찰하였다. 최근의 연구는 주로 거주지 또는 직업적으로 전자기장에 노출된 사람의 암발생 및 출산결과 그리고 신경행동학적인 영향을 조사하기 위한 역학적 조사가 대부분이다. 또한, ELF의 생물학적 영향을 연구하기 위한 실험적 연구도 수행되고 있다. 현재까지의 연구결과를 보면 ELF가 암을 유발한다고 추정은 되지만 확정적으로 단정할 수 있는 증거가 부족하며 암 이외의 생물학적 영향도 추정은 되지만 암과의 연관성보다는 그 근거가 미약하다.

• Clinical and Experimental Pediatrics
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• 제53권9호
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• pp.852-854
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• 2010

Testicular torsion is rare in newborn infants. However, its frequency has increased, most of which are reported in full-term infants. We diagnosed and treated testicular torsion in an extremely low birth weight infant (ELBWI). A $2{\times}2cm$ red mass was palpable in the left groin of a 24-week-old, 745 g, male newborn at 23 days of age. Left testicular torsion was diagnosed, and emergent orchiopexy was performed. Careful physical examination is needed in cases suspicious of testicular torsion in ELBWIs with cryptorchidism. Moreover, early diagnosis and emergent exploration are necessary to prevent complications such as the risk of anorchia.

• 한국산업보건학회지
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• 제32권4호
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• pp.381-392
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• 2022

Objectives: Objective of this study is to review briefly exposure characteristics, monitoring instruments and threshold limit values for extremely low frequency-magnetic field (ELF-MF) methods. This study was undertaken through brief literature review. We performed a literature search in PubMed to identify ELF-MF studies conducted in workplaces. Initial search keywords such as 'extremely low frequency-magnetic field (ELF-MF)' and 'electromagnetic fields (EMF)' combined or singly. We limited our review to occupational rather than general nonworkplace environmental exposures. Methods: The contents we reviewed: key industry and occupations generating ELF-MF, several direct-reading instruments monitoring ELF-MF and threshold limit values (TLV) preventing health effects may be caused by the exposure to ELF-MF. Results: The industries related to the generation and supply of electricity, electrolytic installations, welding, and induction heating and more were regarded as high ELF-MF exposure industries. All jobs handling or employed performed in power cable lines, electrical wiring, and electrical equipment are found to be exposed to ELF-MF. Threshold or ceiling limit, 1,000 µT, is established to prevent acute effects of exposure to low-frequency EMFs on the nervous system: the direct stimulation of nerve and muscle tissues and the induction of retinal phosphenes. The International Agency for Research on Cancer (IARC) has classified ELF-MF as possibly carcinogenic to humans chiefly based on epidemiological studies on childhood leukemia. However, a causal relationship between magnetic fields and several types of cancer including childhood leukemia has not been established nor has any other long-term effects. Risk management using precautionary measures, has been initiated by the US and EU to prevent chronic health effects related to ELF-MF exposure in workplaces. Conclusion: This study recommends the implementation of various measures such as theestablishment of occupational exposure limit values for ELF-MF and precautionary principle to prevent potential chronic occupational health effects may be caused by ELF-MF in Korea.

• 대한의용생체공학회:의공학회지
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• 제24권4호
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• pp.347-354
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• 2003

본 논문에서는 극 저주파와 휴대전화 전자파 (외부전자파) 환경의 영향이 고려된 세포막 활동 전위의 모의실험 모형을 제안하였다. Hodgkin과 Huxley 모형을 기초로 한 이 모형은 주사 전류 (injection current)에 전자파 효과를 적용하였으며 전자파의 주파수 영역에 대한 수치적 모의실험을 통하여 Strength-Duration 곡선을 얻는데 사용되었다 모의실험에서 사용된 수치해석 방법은 Runge-Kutta Fehlberg 방법이다. 모의실험에 고려된 주파수 영역은 1 Hz에서 100 Hz 사이와 이동통신에서 사용되는 900 티Hz의 주파수였다. 모의실험을 통하여 얻은 Strength-Duration 곡선은 Hodgkin과 Huxley가 제안한 방정식과 잘 일치함을 보여주었다.

• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2001년도 Korean Environmental Mutagen Society
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• pp.178-178
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• 2001

• 한국안전학회지
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• 제32권1호
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• pp.33-40
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• 2017

This paper addresses the assessment methods used to evaluate the magnetic exposure of a human to ELF EMF (Extremely Low Frequency Electromagnetic Field) which is caused by the process of power delivery from 60 Hz commercial power. These days the main concern is primarily focused on the magnetic field. For the exposure assessment, both numerical studies and laboratory experiments were studied and the results of the two compared for methodological suitability. The numerical analyses employ the Impedance Method (IM), Boundary Element Method (BEM), and Finite Element Method (FEM) and the laboratory experiments used various human phantom models made with conductivities congruent to human organs and then exposed to uniform/non-uniform magnetic fields to produce eddy currents. Under these conditions a number of examples have been evaluated and the reliability assessed to present the pros and cons of each methodology.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 추계학술대회 논문집 전력기술부문
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• pp.319-321
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• 2007

사회에서 지대한 관심과 논란의 대상이 되고 있는 한전의 고압전력 설비 중 송전선에서 발생하는 ELF(Extremely Low Frequency)전자계 저감을 위한 사회적비용의 계량화에 관한 연구를 하였다. 송전선로에서 발생되는 극저주파 전자계와 토지가격 사이의 관계론 규명하는 본 연구는 분서의 틀로서 극저주파 전자계 저감을 위한 다양한 기법에 대해서 제시하였다. 또한 다양한 황경가치 평가기법을 비교 분석한 결과, 헤도닉가격법이 가장 적정한 것으로 판단되어 이 분석법을 본 연구의 주된 분석도구로 삼고자 한다. 최근 환경질의 가치평가 기법으로 가장 광범위하게 사용되고 있는 기법중 하나인 헤도닉가격법은 기본적으로 주택, 토시 같은 재화는 그 자체가 가진 물리적 특성뿐만 아니라 외적인 환경 등 다양한 특성으로 이루어진 차별적 재화(differentiated product)라는 헤도닉가설(hedonic hypothesis)을 전제로 한다.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.13-17
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• 2003

In this paper, the design parameters for the magnetic field source at extremely low frequency are proposed. This facility can be used for in vivo experiments with small animals to investigate biological response to the driving magnetic fields. In case that the exposed animals are motionless, the animals may be affected by the directivity of driving field. To avoid this effect, a 2-axis ELF magnetic field driving apparatus was designed, The optimum location and number of turns of each coil were obtained by numerical analysis. Applying these data to the MATLAB code (for computation), the magnetic field distribution was obtained. The calculation result for a well-designed facility showed that the space in which the amplitude of the magnetic field lies within the 95% of the magnetic field distribution was more than 60% of each axis length.