• Journal of the Korean Society of Radiology
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• v.7 no.1
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• pp.45-50
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• 2013

Non-invasive technique CT, called automated computed tomography, is used to detect lesion of a patient when diagnosing human body. Information obtained from CT plays an important role in assembling 3 dimensional images. Recently, new equipment, operated by CT, is required which can be appliable to physical and biological research. In accordance to this quest, micro-CT is invented that produce more detail and concrete information. Images supplied by CT are even more detailed and concrete, so it contributes much to the development of biology and polymer material engineering field. However, there has been little reliable reports regarding measuring information of space dose distribution about exposure dose limit of users operating micro-CT. In addition, little reports regarding space dose distribution of exposure has been known about unwanted diffraction light produced by usage of micro-CT. The exterior of micro-CT is covered by lead, which is for removing exposure of diffraction light. Thus, even if it is good enough to prevent exposure of diffraction light, consistent management of equipment will be required as time goes by and equipment are getting old as well. We measured space dose distribution regarding exposure of diffraction light of users operating micro-CT directly. Therefore, we suggest that proper management should be necessary for users operating micro-CT not to be exposed by unwanted diffraction light.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.3
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• pp.184-193
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• 2016

Purpose: To evaluate marginal leakage of bulk fill flowable composite resin filling with different curing time by using microcomputed tomography technology. Materials and Methods: 30 previously extracted human molars were randomly divided into 6 groups based upon restorative system and different curing time. Class II cavities (vertical slot cavities) were prepared. An individual metallic matrix was used to build up the proximal wall. The SonicFill or SureFil SDR flow was inserted into the preparation by using 1 bulk increment, followed by light polymerization for different curing times. The different exposure times were 20, 40, and 60 seconds. All specimens were submitted to 5,000 thermal cycles for artificial aging. Micro-CT scanning was performed by using SkyScan 1272. One evaluator assessed microleakage of silver nitrated solution at the resin-dentin interface. The 3D image of each leakage around the restoration was reconstructed with CT-Analyser V.1.14.4. The leakage was analyzed with the Mann-Whitney test. Results: Significant differences were observed between the light curing times, but no significant differences were found between the bulk fill composite resins. Increasing in the photoactivation time resulted in greater microleakage in all the experimental groups. Those subjected to 60 seconds of light curing showed higher microleakage means than those exposed for 20 seconds and 40 seconds. Conclusion: Increasing the photoactivation time is factor that may increase marginal microlekage of the bulk fill composite resins. Further, micro-CT can nondestructively detect leakage around the resin composite restoration in three dimensions.

• Proceedings of the Korea Information Processing Society Conference
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• 2021.11a
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• pp.997-1000
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• 2021

본 연구는 버스환승정보센터의 디지털기기에 마이크로 인터렉션을 적용하여 UI를 설계한다. UI를 설계하면서 디지털기기에 사용이 어려운 고령자의 특성을 물리적, 인지적 기준으로 분류하고 문제점을 파악하여 지금까지 연구되어온 타이포그래픽, 컬러 등의 그래픽적 요소가 아닌 마이크로인터렉션 효과를 적용하여 고령자에게 디지털기기의 사용성을 높이기 위한 UI를 설계하였다.

• Journal of Internet of Things and Convergence
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• v.7 no.2
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• pp.1-6
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• 2021

In recent years, many people are living in a space limited by rapid global industrial development and economic growth, and rapid urbanization is underway, with the global urban population estimated to be more than 70 percent in 2050. Due to rapid urbanization, government-led smart city models are being developed and introduced to solve various urban problems such as disaster safety, air pollution, water pollution, energy shortage, disease, crime and transportation. However, since ICT technology of public housing is being developed as a type of social overhead capital project, it is necessary to develop micro-smart city projects that residents can feel by developing services such as public safety, living environment, living welfare, and energy management for public housing residents. Therefore, in this paper, the smart platform model of public housing for smart city in the era of the Fourth Industrial Revolution is planned and presented.

• Magazine of RCR
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• v.18 no.4
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• pp.56-63
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• 2023

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.63-63
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• 2004

기계류는 대개 부정형의 형상을 지니고 있으며, 또 표면이 모두 연결되어 있으므로, 진동하는 물체 표면상에서의 소음원 특성을 세밀히 파악하는 일은 매우 어려운 일이다. 음향 인텐시티나 공간 푸리에 변환을 이용하는 홀로그래피 기법 등의 어레이 마이크에 의한 기법들이 제안되었고 또 활용되고 있으나, 이는 어디까지나 음원에서 가까운 음장을 가상적인 음원면이라 보고 재구성하는 것이어서 실제 음원의 특성을 파악하는데 어려움이 있다. 이러한 문제점을 해결하기 위해 음원표면을 경계요소화 모델링을 하고, 어레이 마이크로 측정될 음장의 지점과 표면간의 관계를 수학적으로 정리한 후, 마이크에서 측정된 신호를 이용해 역으로 경계요소해석 계산을 수행하여 음원 특성을 파악하는 기법이 제안되었다. 본 발표에 있어서는 이와 같은 취지에서 ‘개발된 Inverse BEM을 이용한 NAH 기법’에 관한 개괄적인 내용을 설명하고, 그 적용 가능성 및 이 기법의 미래에 대해 설명하며, 다음과 같은 내용의 순서대로 설명된다: $\textbullet$ 각종 음원 파악 기법들의 특성과 이 방법이 필요한 이유 $\textbullet$일반 음향 holography 기법 (STSF)과의 차이점 $\textbullet$ 이론적 배경 개괄 $\textbullet$ 실제 적용 순서에 따른 방법의 설명 $\textbullet$ 후처리 결과물 $\textbullet$ 본 기법의 향후 과제 및 적용 방법의 개선

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.6
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• pp.638-647
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• 2003

Triangular patches have been studied, both theoretically and experimentally. We feund that provided radiation characteristics similar to those of rectangular patches, but with smaller size. In this paper, we designed an equilateral triangular microstrip patch antenna using cavity model analysis. Then, in order to improve narrow bandwidth, we add capacitive gap and air gap. Capacitive gap is located with square shape beside feeding point on the patch, and air gap is inserted between substrate dielectric and ground plane to adjust probe inductance. The analysis of characteristics and effects of each component was performed by commercial simulation tool, Ensemble 5.0. Throughout the simulation and experiment, we found the possibility of bandwidth enhancement in triangular microstrip antenna.

• 정보화사회
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• s.151
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• pp.32-37
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• 2001

본 협회에서는 지난 6월 22일 센트럴 시티 5층에서 차세대 IT 산업의 육성.발전을 위해 POST PC(PDA, Thin Client 등), 음성정보처리산업 및 임베디드 리눅스에 대한 기술 및 산업 동향과 기술개발 정책방향 등을 소개하고 산학연 전문가 의견을 수렴하여 관련 산업의 바람직한 발전방향을 제시하기 위해 "차세대 IT 산업 활성화 세미나"를 개최했다. 정보통신부 손홍 국장을 비롯하여 LG전자 백우현 사장, 한국 IBM 신재철 사장, 마이크로소프트 고현진 사장, 대우전자 강탁명 전무 외에도 업계 관계자 및 일반인 등 총 320여명이 참석한 이번 세미나를 정리했다.

• Korean Journal of Digital Imaging in Medicine
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• v.15 no.1
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• pp.33-38
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• 2013

Bone is so crucial anatomy for human body. Many researchers study deep into a subject about bone regeneration. There is no standard analysis for quantitative Neo-bone regeneration on calvarial defected model. Micro CT is so useful method to quantitative analysis of Neo-bone regeneration. This study was show that how to quantitative analysis of Neo-bone regeneration with ${\mu}-CT$ Micro CT was possible to quantitative analysis for Neo-bone regeneration on Calvarial defected model. futhermore Not only was Micro CT possible for qualitative analysis but quantitative analysis on the mouse calvarial model. This study will provide bone biology researchers with accurate quantitative analysis.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.3
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• pp.269-275
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• 2022

In this study, the setting time and compressive strength of cement paste composites applied with nano-micro pozzolanic binders were experimental analyzed. The pozzolanic binder was reduced initial and final setting time and the compressive strength was increased. Micro silica was effective in decrease the initial setting and final setting time and impressing the compressive strength. When two or more cement binders were used, the using of silica fume and a small amount of nano silica at reduced the setting time to 62-64 % to OPC cement and the compressive strength was increased to 117 %. A small amount of mixing the nano silica was effect to pore filling and pozzolanic activation. However, the addition of a chemical admixture should be considered when mixing table design because pozzolanic binders high specific surface area causes a decrease in cement composites flow.