• Korean Architects
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• no.2 s.167
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• pp.82-87
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• 1983

• Journal of the Korean Society of Radiology
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• v.11 no.6
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• pp.423-428
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• 2017

In this study, the calculation of the effective spatial dose distribution of the diagnostic imaging laboratory of K university was performed by the Monte Carlo simulation. The radiation generator has a maximum tube voltage of 150 kVp and a maximum current of 700 mA. Using the results, we compared the spatial effective dose distributions of diagnostic imaging laboratory when the shielding door was closed and opened. In conclusion, it was found that the effective dose in the operating room of the diagnostic imaging laboratory does not exceed the annual dose limit (6 mSv/y) of the student (occasional visitor) even when the door is opened. However, since the effective dose when the door is open is about 16 times higher in front of the lead glass window and about 3,000 times higher in front of the doorway than the case when the door is closed, closing the shielding door at the time of the practical exercising reduces unnecessary radiation exposure by great extent.

• Journal of the Korean Society of Mineral and Energy Resources Engineers
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• v.55 no.6
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• pp.596-603
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• 2018

The traffic congestion is frequently occurring due to increasing demand for vehicles and development of subcenter in roads of domestic-downtown. The design of a Great depth underground double-deck tunnel planned for construction as a solution however it's mainly for a compact-car. Its low height and small section cause causalities when fire occurs. From this study, the delay system for fire smoke diffusion is developed to minimize the occurrence of casualties when fire occurs in the Great depth underground double-deck tunnel and the CFD(Computational Fluid Dynamics) is used to find the optimal installation interval and the blockage ratio to maximize the system effects. The study analyzed the shorter the installation interval of the system, the higher the smoke delay effect but the efficiency-change tends to be slight above a certain distance and the larger the blockage ratio, the higher the effect but the efficiency-difference is slight according to installation interval.

• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.192-193
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• 2009

• Journal of radiological science and technology
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• v.38 no.3
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• pp.199-203
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• 2015

Panoramagraphy was the second most used intraoral radiography utilized in Korea, resulting in 17.8% in university dental hospitals, 24.8% in dental hospitals, and 31.4% in dental clinics. Depending on increased demand like orthodontics and implant, panoromagraphy tends to consistently increase. This study were used lead glasses and lead shielding to reduce unnecessary radiation to the eyeballs and thyroid. ESD was 41.4% when radiation was shielded with the lead glasses while reducing 47.3% of ESD by shielding the X-ray tube area with shielding lead. There was no statistically significant difference. The lead glasses is appropriated to reduce unnecessary radiation exposure to the eyeballs.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.2
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• pp.109-112
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• 2007

The possibility and limitation of one dimensional nano scale electron shielder is briefly discussed. A Nano scale electron shielder will reduce the weight and size of shielding materials. However, practical application still requires further research. In this work, we discuss general problems related to nano scale electron shielder, by taking an arbitrary one dimensional potential barrier as an example.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.635-642
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• 2020

The purpose of this study was to analysis the effects of shielding area of field configuration with changing of sensitivity and density on tube current (milliampere-seconds, mAs) and image quality in automatic exposure control (AEC) system. The equipment used a digital radiography device (Digital Diagnost, Philips, Netherlands), which has a integral type with an X-ray tube and an indirect digital detector. The AEC system conditions were consisted of 9 setting environments, that mode changing of the sensitivity (S200, S400, S800) and the density (+2.5, 0, -2.5). The tube current evaluated automatically exposed mAs under 81 combination conditions crossed by AEC conditions in fixed at 40 kVp. The image quality evaluated the radiographic images that selected valid images by visual assessment the radiographic images of the self-produced conical pyramid phantom and then measured their signal to noise ratio (SNR). As a result, the maximum tube current was 60.0 mAs that automatically exposed conditions were the 100% of shielding area and the sensitivity of S200 and the density of +2.5. The minimum tube current was 0.9 mAs with non-shielding area and the sensitivity of S800 and the density of -2.5. When the shielded area 0% with the sensitivity of S200 and the density of +2.5, the maximum SNR was the highest as 25.2. But when the shielded area 25% with the sensitivity of S800 and the density of -2.5, the minimum SNR was the lowest as 4.7.

• 대한방사선방어학회:학술대회논문집
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• 2010.04a
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• pp.232-233
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.55-55
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• 2004

최근 전기 전자 장치의 사용이 급속하게 증가하고 있다. AC모터, 프린터, 디지털 컴퓨터, 계산기, 핸드폰 등과 같은 장비들은 많은 전자파를 방출하고 있다. 이러한 전자파에 노출로 암과 같은 질병이 발생할 수도 있다는 논란이 전 세계적으로 관심이 집중되고 있으며, 전자파에너지를 차패할 수 있는 재료 개발의 필요성이 절실히 요구되고 있는 실정이다. 일반적으로 금속과 합금이 전자파 차폐목적으로 사용되었다 그러나 이러한 재료들은 중량이 무겁고 가요성이 떨어지는 단점이 있다.(중략)

• JOURNAL OF ELECTRICAL WORLD
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• no.4 s.208
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• pp.17-25
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• 1994