• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.1023-1026
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• 2013

The electronic equipment which was exposed to high level pulsed radiation is damaged as Upset, Latchup, and Burnout. Those damages has come from the instantaneous photocurrent from electron-hole pairs generated in itself. Such damages appeared as losses of power in military weapon system or of blackout in aerospace equipment and eventually caused in gross loss of national. In this paper, we have implemented a RDC(Radiation detection and control module) as part of the radiation protection technology of the electronic equipment or devices from the pulsed gamma radiation. The RDC which is composed of pulsed gamma-ray detection sensor, signal processors, and pulse generator is designed to protect the important electronic circuits from the pulse radiation. To verify the functionality of the RDC, LM118s which had damaged by the pulse radiation were tested. The test results showed that the test sample applied with a RDC was worked well in spite of the irradiation of the same pulse radiation. Through the experiments we could confirm that the radiation protection technology implemented with RDC had the functionality of radiation protection to the electronic devices.

• Journal of radiological science and technology
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• v.30 no.3
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• pp.265-270
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• 2007

The purpose of this study was to evaluate the possibility of utilizing MT pulse at CE-TOF-MRA in patients with cerebral infarction. MRA using time-of-flight(TOF) technique with varying offset frequencies (0, 600, 1,200, and 1,800 Hz) magnetization transfer were performed in 10 patients with cerebral infarction at 3.0T MR scanner. CE-TOF-MRA and TOF-SPGR in normal vessel shown decreased SNR and increased CNR. The highest CNR in narrowing vessel shown at CE-TOF-MRA using 600 and 1,200 Hz offset frequencies. CNR in stenosis vessel increased dependent on using offset frequencies. The occlusion was clearly shown, and the highest CNR in occlusion shown at CE-TOF-MRA using 1,800 Hz offset frequencies. There was no shape variation in narrowing vessel or no visualizing vessel.

• Journal of Radiation Protection and Research
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• v.12 no.1
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• pp.12-25
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• 1987

A basic multichannel analyser (MCA) system have been designed and constructed with the successive approximation type ADC (Analog to Digital Converter). Linear Gate, window, and palse stretcher consist of mainly linear and logic IC's, and are properly combined together to achieve short dead time and good linearity of the system. ADC 1211 (analysing time: $120{\mu}sec$) and S-RAM (static random acess memory) 6264 are used in ADC module. Two 6264 memories are connected in parallel in order to-provide enough counting capacity ($2^{16}-1$). Interfaced microcomputer Apple II controls this system and analizes the counted data. The system is tested by input pulses between 0V to 10V from oscillator.

• Journal of the Korean Society for Railway
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• v.15 no.2
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• pp.116-121
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• 2012

DC/DC switching power converters produce DC output voltages from different DC input sources. The converter is used in regenerative braking of DC motors to return energy back in the supply, resulting in energy savings for the systems containing frequent stops. The DC/DC converter is composed of a PWM-IC (pulse width modulation integrated circuit) controller, a MOSFET (metal-oxide semi-conductor field-effect transistor), an inductor, capacitors, and resistors, etc. PWM is applied to control and regulate the total output voltage. In this paper, radiation shows the main influence on the changes in the electrical characteristics of comparator, operational amplifier, etc. in PWM-IC. In the PWM-IC operation, the missing pulses, the changes in pulse width, and the changes of the output waveform are studied by the simulation program with integrated circuit emphasis (SPICE) and compared with experiments.

• Journal of radiological science and technology
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• v.30 no.4
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• pp.427-433
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• 2007

This study was conducted to investigate the usefulness of PASL image technique through visual and quantitative assessment by dividing CBF image, conventional perfusion magnetic resonance image, anterior cerebral artery, middle cerebral artery and posterior cerebral artery into 6 territories both right and left in moyamoya disease. In visual assessment, the scope of decreased perfusion in the PASL CBF image and conventional perfusion MR CBF image agreed with the position of deficiency in the MR image. The quantitative assessment, showed that the scope and position of decreased perfusion accord with both in the PASL CBF image and the existing conventional perfusion MR CBF image but the assessment of measuring the quantity of perfusion according to signal intensity showed a little difference.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.695-703
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• 2020

The use of medical devices is increasing due to the development of medical technology. Among medical devices, it is often used in the human body for graft and treatment. Therefore, in medical institutions, various sterilization methods according to the type and material of medical devices are applied to prevent infection. Hydrophosphite (HA) materials are the most popular in bone grafts. We would like to present a sterilization method using Q-switch Nd:YAG laser with high output energy among non-ionizing radiation suitable for small medical devices. In this study, sterilization power was most ideally shown at UV wavelengths of 1.5 W, 266 nm, and 10 pulses. Different wavelength bands; infrared and visible light; showed passive sterilization, and ultraviolet A and C showed differences in sterilization according to the pulse. In laser sterilization were differences that found according to the wavelength bands and pulses.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.248-251
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• 2013

The purpose of this study was to investigate the inactivation effect of intense pulsed light (IPL) on Micrococcus roseus, an irradiation-resistant bacterium isolated from laver, and the commercial feasibility of this sterilization method on dried laver. The inactivation of M. roseus in cultivated plates increased with increasing light intensity and treatment time. Approximately 6.6 log CFU/mL reduction of the cell viability was achieved with IPL treatment for 3 min at 1,000 V of light intensity, tailing was not shown. In addition, the inactivation rate of M. roseus increased with increasing pulse number at same light intensity and treatment time. The killing efficiency for M. roseus increased with by decreasing the distance between the light source and the sample surface.

• 대한방사선방어학회:학술대회논문집
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• 2011.04a
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• pp.40-41
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• 2011

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.880-883
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• 2012

In this paper, CMOS logic device, the INVERTER, NAND, NOR were designed and fabricated using 0.18um CMOS process for analyzing the effect of transient radiation damage. Fabricated logic devices were measured by applying a 1kHz input at 1.8V supply. As a result, the current consumption of less than 70uA and Rising time, Falling time was within a 4us. Experimental results transmission delays occurred when using a 50M cable for pulse radiation experiments.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.778-781
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• 2012

The electronic element the damage occurs with radiation being bombed. In order applies in the artificial satellite or the space ship therefore from the within has radiation introspection the use of the radiation electronic element is essential. Transient radiation tests performed for the first time in Korea evaluation data database (DB) was constructed to. Web-based materials in the DB is designed to be able to search and update, and existing foreign (NASA, ESA) for a total of 695 species, including public sources of data has been entered. Search DB than the existing foreign DB is an efficient and practical.