• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.948-949
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• 2016

In this study, we perform the structure change of the shielding this is applied for gamma-ray detectors for imaging of gamma-ray source. Through previous studies, we implemented the commercially available gamma-ray imaging apparatus similar to the shielding body but weight reduction, center of gravity moving of shield. In this paper, we changed a shield for motion control detectors efficient movement. We performed the MCNP simulation of shield design and then we obtained the results of reducing the weight of the 17% and moving of center of gravity the shield center.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.773-774
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• 2016

In this study, we perform the weight reduction and miniaturization of the shielding element that is applied for gamma-ray detectors for imaging of gamma-ray source. Through previous studies, we implemented a lead-based shielding element that represents the shielding effectiveness and performance of commercially available gamma-ray imaging apparatus similar to the shielding body. In this paper, we designed a tungsten-based shield for weight reduction and miniaturization than lead-based shield. We performed the MCNP simulation for shield design and then we obtained the results of reducing the weight of the 17% and 51% of the volume.

• Journal of Radiation Protection and Research
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• v.39 no.1
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• pp.21-29
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• 2014

A new cold neutron triple-axis spectrometer (Cold-TAS) was recently constructed at the 30 MWth research reactor, HANARO. The spectrometer, which is composed of neutron optical components and radiation shield, required a redesign of the segmented monochromator shield due to the lack of adequate support of its weight. To shed some weight, lowering the height of the segmented shield was suggested while adding more radiation shield to the top cover of the monochromator chamber. To investigate the radiological effect of such change, we performed MCNPX simulations of a few different configurations of the Cold-TAS monochromator shield and obtained neutron and photon intensities at 5 reference points just outside the shield. Reducing the 35% of the height of the segmented shield and locating lead 10 cm from the bottom of the top cover made of polyethylene was shown to perform just as well as the original configuration as radiation shield excepting gamma flux at two points. Using gamma map by MCNPX, it was checked that is distribution of gamma. Increased flux had direction to the top and it had longer distance from top of segmented shield. However, because of reducing the 35% of the height, height of dissipated gamma was lower than original geometry. Reducing the 35% of the height of the segmented shield and locating lead 10cm from the bottom of the top cover was selected. After changing geometry, radiation dose was measured by TLD for confirming tester's safety at any condition. Neutron(0.21 ${\mu}Svhr^{-1}$) and gamma(3.69 ${\mu}Svhr^{-1}$) radiation dose were satisfied standard(6.25 ${\mu}Svhr^{-1}$).

• 대한방사선방어학회:학술대회논문집
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• 2011.11a
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• pp.366-367
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• 2011

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.856-857
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• 2015

본 논문은 소형 무선충전장치 등에 충전기 기능을 비접촉(무선)방식으로 구현할 때 발생되는 차폐 재료의 전자기적 해석과 측정 결과를 비교한 것으로 전자차폐 재질의 투자율, 두께, 부하크기, 차폐층의 크기 등을 변수로 하여 전자기적 특성을 전자장해석프로그램(FLUX)을 이용하여 해석 분석하여 실험 장치를 이용하여 측정결과를 계산결과와 비교한 것으로 무선충전장치 차폐 재료 개발에 정보를 제공하는 것이다.

• Journal of radiological science and technology
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• v.27 no.4
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• pp.23-29
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• 2004

The application of analytical model(Archer et al. 1983) to shielding calculations in diagnostic radiology combined with measurements of the broad beam transmission properties of lead, steel, concrete, and plate glass for x-ray tube potential of 60-140 kVp using an x-ray inverter generator and total initial beam filtration sufficient to provide half-valve layer representative of those found in common practice and required by regulatory agencies. Our transmission measurements and numerical fits to the mathematical model of broad beam transmission(Archer et al. 1983) will assist medical or health physicist faced with the task of designing protective barriers for medical diagnostic x-ray facilities.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1994.04a
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• pp.167-171
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• 1994

본 연구에서는 차폐구조 내부에 위치한 소음원의 체적이 비교적 큰 근접 음향 차폐구조로 취급하여, 구조 내부의 공간적 음장분포해석(spatial sound distribution analysis)은 하지 않고 단지 소음원의 표면과 차폐 벽면 간의 공기층에 의한 간섭 영향을 고려하면서, 차폐로 인한 음압의 상승(build up)효과를 고려하여, 직육면체의 형상을 가지는 차폐구조에 부착되는 각각의 벽면들의 음향 삽입손실(Insertion Loss, IL) 특성을 전달매트릭스 기법(Transfer Matrix Analysis, TMA)을 이용하여 해석하였으며, 이러한 벽면들에 대한 이론 해석의 결과로 제작된 벽면들의 음향차폐특성을 시험을 통해 나타내었다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.944-945
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• 2016

Gamma-ray Detector for gamma-ray imaging device is composed of a shielding body for shielding gamma-rays incident from the radiation source. Distribution of the gamma ray can be represented by the distribution information on the direction in which the detecting section and the signal through the incident hole of collimator. The role of the shield is important because all signals should be treated as noise except for the signal from the incident hole.In this paper In this paper, we have produced a compact, lightweight and Collimator shield by changing the structure and physical properties with respect to the collimator and shielding of lead-based gamma-ray detectors. And we analyzed the shielding effectiveness relative to the incident gamma ray sphere measured signal value through the gamma irradiation test facility. The results confirmed that the production and Collimator shielding the imaging device Implementing more efficient to implement.

• Journal of the Korea Institute of Military Science and Technology
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• v.2 no.1
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• pp.82-89
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• 1999

In this article, the performances of acoustic enclosure with double resilient mount system which was designed by ADD to reduce the radiated noise by main noise source of ships, was tested and evaluated. From test results, it was verified that the acoustic performances of acoustic enclosure satisfied the requirements; vibration isolation level at 1st stage mount system of 15 ㏈ and airborne noise reduction level of 20 ㏈ in broad band.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.431-436
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• 2021

In this study, a new shielding method was applied to an accessory device that produces electromagnetic waves in the magnetic resonance room to prevent the generation of artifact caused by electromagnetic waves. The research method applied a new shielding made of metal plating fiber to patient surveillance CCTVs without shielding technology, and obtained and evaluated noise map when the power was not cut off and when the new shielding technology was applied without shutting down the CCTV. As a result of the study, it was found that there was at least one group with significant differences. Type I and type III belonged to group 1 while type II belonged to group 2 in the Post-hoc analysis, which meant blocking power of the CCTV and the applying new shielding technology were in the same group. In conclusion, if electromagnetic waves are generated due to additional accessories in the scanning room, the shielding material proposed in this study should be applied which enables the electric state become similar to type I, not generating noise, thereby preventing the artifacts caused by electromagnetic waves.