• Journal of electromagnetic engineering and science
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• v.15 no.3
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• pp.151-157
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• 2015

The increasing use of mobile phones has raised public concern about the possible biological effects of radiofrequency electromagnetic field (RF-EMF) exposure on the human brain. To investigate the potential effect of RF-EMF exposure on the brain, we examined the behaviors and hippocampal morphology of C57BL/6 mice after sub-chronic exposure to RF-EMFs with a relatively high SAR level (5.0 W/kg). We applied a 2-hour daily exposure of WCDMA 1,950 MHz using a reverberation chamber that was designed for whole-body exposure for 60 days. In the behavioral tests, RF-EMF did not alter the physical activity or long-term memory of mice. Moreover, no alteration was found in the neuronal and glial cells in the hippocampus by RF-EMFs. In this study, we showed that sub-chronic whole body RF exposure did not produce memory impairment and hippocampal morphological alteration in C57BL/6 mice.

• Transactions on Electrical and Electronic Materials
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• v.7 no.5
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• pp.240-246
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• 2006

The mathematical model of the power substation is proposed. The substation esteems as a set of the equipment elements which integrated common connections and electromagnetic field. Some capabilities of model represented by both electric networks and a discrete logical model demonstrated by non-directional graph. The model can be useful for solution of the problem of diagnostic of the high-voltage equipment.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1672-1675
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• 2003

Microstrip antennas have many applications in wireless communication system. This paper propose a analytical far-field pattern of radiation for application of the wireless communication. The triangular slot antenna fed by micorstrip line is proposed at resonance frequency 10 GHz. The simulation results of the electromagnetic field radiation pattern, S parameter, characteristic of input impedance are obtain by using the finite difference time domain (FDTD) method. The analytical space in FDTD analysis are $50{\times}171{\times}120$ cells with the cell dimension ${\Delta}x=0.152\;mm$, ${\Delta}y={\Delta}z=0.15\;mm$.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.9 no.6
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• pp.23-31
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• 1995

As a study on electromagnetic radiation emission from the neon signs, this paper has investigated the characteristics of frequency bands and spectra intensities under the operations of the sign's OFF, ON/OFF and continuous ON states. Also we have studied the above characteristics when a distance between the sign and the antenna is varied. All data were obtained in the range of 0.1∼1,000[MHz] by using spectrum analyzer along with the loop, biconical and log periodic antenna. As the result, we found that the radiated electromagnetic waves of the sign at continuous ON states were measured only in the range of 30∼400[MHz] but those of the sign at ON/OFF states were appeared widely in the range of 2∼1,000[MHz].

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.6
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• pp.74-80
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• 2008

Analysis of the electromagnetic environment on topside of a ship is needed for optimal arrangement of all kinds of antennas to be installed on the shipboard in order to minimize the probability of EMI of equipment and subsystems in real ship after construction phase. In this paper we analyze the characteristics of electric-fields such as radiation patterns and near E-fields of V/UHF antennas installed on a shipboard. We compare simulated results with measurements on the real ship for near E-fields to verify the reliability of the computed electromagnetic environment. Although there are various factors causing errors such as cable loss and impedance mismatching etc. when measuring near E-field, both data show similar trends in the range of the acceptable tolerance.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.1099-1100
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• 2008

In this paper, we would like to introduce a simple and low cost wired pointing device by using a electromagnetic induction. A number of patents of Wacom describe electronic drawing devices or styluses. The movement of the stylus over a tablet is traced electronically and used applied to a resonant circuit in the stylus. Electromagnetic radiation emitted by the resonant circuit is detected by a sensing mechanism and location processing is used to locate the stylus. In this research, difference coil principle is used to detect the emitted radiation of the resonant circuit in the pen. This detection device shows good performance to detect the location of the pen on the tablet.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.6
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• pp.725-734
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• 1998

When the EED is exposed to the high power radiation, it is possible to verify systems survivability through measuring the induced current of EED. The usual method of performing a system level test is to replace the EED's with modified units from which the explosive charge has been removed and replaced with the fiber optic sensor. The thermal transient test was performed to obtain the temperature vs current characteristic curve for optical sensor installed in EED. The currents measured when the system is exposed to a known EME are compared to the proposed specfication about the EED and a decision is made on whether system is safe or not.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.2
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• pp.151-154
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• 2020

Radiation noise due to EMI noise generated by the driving circuits of LED lighting devices in a medical imaging room was reduced by decreasing the noise source in the driving circuits and changing the number of corrections in EMI filters. Noise attenuation and filter changes enabled driving circuits that reduced the electromagnetic waves. Such circuits were efficiently designed by using capacitors and inverters in a given space. Therefore, the malfunction of radiation devices can be minimized by using EMI-reduction filter circuits, and reliable operation of medical devices can be expected by blocking electromagnetic waves.

• IEIE Transactions on Smart Processing and Computing
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• v.5 no.1
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• pp.63-69
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• 2016

This paper presents methods to improve the effectiveness of electromagnetic shielding. The slit appears in an enclosure's surface to ventilate. Slits may also appear due to power supply lines or to serve as a communication link between electronic circuits inside and outside the box. We simulated electromagnetic radiation in different conditions in order to propose a method to improve the effectiveness of electromagnetic shielding to ensure electromagnetic compatibility using CST software (Computer Simulation Technology).

• ETRI Journal
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• v.41 no.6
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• pp.731-738
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• 2019

We proposed a novel electromagnetic band-gap (EBG) cell-embedded antenna structure for reducing the interference that radiates at the antenna edge in wireless access in vehicular environment (WAVE) communication systems for vehicle-to-everything communications. To suppress the radiation of surface waves from the ground plane and vehicle, EBG cells were inserted between micropatch arrays. A simulation was also performed to determine the optimum EBG cell structure located above the ground plane in a conformal linear microstrip patch array antenna. The characteristics such as return loss, peak gain, and radiation patterns obtained using the fabricated EBG cell-embedded antenna were superior to those obtained without the EBG cells. A return loss of 35.14 dB, peak gain of 10.15 dBi at 80°, and improvement of 2.037 dB max at the field of view in the radiation beam patterns were obtained using the proposed WAVE antenna.