• 구강회복응용과학지
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• 제31권3호
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• pp.178-185
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• 2015

목적: 본 연구에서는 Simplant와 R2GATE 두 가지 수술용 가이드 시스템의 인터페이스(interface)에 대한 만족도, 제작된 수술용 가이드의 디자인과 편의성, 수술용 가이드 활용 시 중요도에 대한 만족도를 설문조사하여 비교평가 하고자 하였다. 연구 재료 및 방법: 두 가지 시스템으로 제작된 수술용 가이드(surgical guide)를 치아모형에 각각 장착한 상태에서 임플란트 수술 과정을 모의하였다. 모의 수술이 끝난 뒤 연구대상에게 만족도에 관한 설문지를 작성하도록 하였다. 작성된 설문지를 회수하여 각 문항에 대한 데이터를 정리하고 통계 프로그램 SPSS 20.0 (IBM)를 이용하여 분석하였다. 결과: 전체적인 만족도는 R2GATE 군($7.33{\pm}1.26$)이 SimPlant 군($6.67{\pm}1.26$)보다 더 높은 것으로 나타났다(${\alpha}$ = 0.05). 결론: R2GATE 시스템으로 제작된 수술용 가이드는 임상에 널리 사용 할 만 한 사용자의 만족도를 나타내었다. 또한, R2GATE 시스템으로 제작된 수술용 가이드는 drill의 길이와 방향을 동시에 guide할 수 있어 임플란트 식립 경험이 부족한 초심자에게 적극 추천된다.

• Current Optics and Photonics
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• 제2권3호
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• pp.269-279
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• 2018

We are currently investigating the feasibility of a 1.6 m telescope with a laser-guide star adaptive optics (AO) system. The telescope, if successfully commissioned, would be the first dedicated adaptive optics observatory in South Korea. The 1.6 m telescope is an f/13.6 Cassegrain telescope with a focal length of 21.7 m. This paper first reviews atmospheric seeing conditions measured over a year in 2014~2015 at the Bohyun Observatory, South Korea, which corresponds to an area from 11.6 to 21.6 cm within 95% probability with regard to the Fried parameter of 880 nm at a telescope pupil plane. We then derive principal seeing conditions such as the Fried parameter and Greenwood frequency for eight astronomical spectral bands (V/R/I/J/H/K/L/M centered at 0.55, 0.64, 0.79, 1.22, 1.65, 2.20, 3.55, and $4.77{\mu}m$). Then we propose an AO system with a laser guide star for the 1.6 m telescope based on the seeing conditions. The proposed AO system consists of a fast tip/tilt secondary mirror, a $17{\times}17$ deformable mirror, a $16{\times}16$ Shack-Hartmann sensor, and a sodium laser guide star (589.2 nm). The high order AO system is close-looped with 2 KHz sampling frequency while the tip/tilt mirror is independently close-looped with 63 Hz sampling frequency. The AO system has three operational concepts: 1) bright target observation with its own wavefront sensing, 2) less bright star observation with wavefront sensing from another bright natural guide star (NGS), and 3) faint target observation with tip/tilt sensing from a bright natural guide star and wavefront sensing from a laser guide star. We name these three concepts 'None', 'NGS only', and 'LGS + NGS', respectively. Following a thorough investigation into the error sources of the AO system, we predict the root mean square (RMS) wavefront error of the system and its corresponding Strehl ratio over nine analysis cases over the worst ($2{\sigma}$) seeing conditions. From the analysis, we expect Strehl ratio >0.3 in most seeing conditions with guide stars.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.60-63
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• 2004

An innovative in-core neutron flux mapping system has been developed and applied successfully for service in a commercial pressurized water reactor. With the benefit of double indexing path selector (Dip $s^{ⓡ}$) mechanism, the reliability of the detector drive system has been improved five times higher than that of conventional systems, and the problems caused by the serious friction generated between the detector cable and guide tubing has been solved completely because the Dip $s^{ⓡ}$ architecture allows the detector guide tubings to have larger curvature and shorter length in nature. The simple and fast maintenance is particularly emphasized in the detector drive system to secure minimum radiation exposure to the maintenance personnel by optimizing the number of components and providing easy access to the components. The programmable logic controller based digital controller with Window $s^{ⓡ}$ based operator s console provides fully automated and user friendly operation and maintenance support means.

• 동력기계공학회지
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• 제10권2호
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• pp.16-21
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• 2006

On this study, numerical analysis was performed for the 3 dimensional flow field of gas and particle phase for axial inlet cyclone, a part of dust collector. We applied FVM to visualize the gas phase. The flow was solved using ${\kappa}-{\varepsilon}$ turbulence model. The major parameters considered in this study were helical guide vane, inner diameter, length. Particle trajectory calculations were performed for the particle sizes of $5{\mu}m{\sim}75{\mu}m$. The distribution curve of particle sizes was made of Rosin-Rammler function. The simulation results show various gas flows, particle trajectories on numerical models.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 춘계학술대회
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• pp.166-168
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• 2016

이 논문은 포켓 구조 터널링 전계효과 트랜지스터의 구조에 대한 여러 가지 조건을 소개한다. 포켓의 길이는 길어질수록 $I_{on}$이 더 증가하고, 포켓의 두께는 감소할수록 $I_{on}$이 증가하고, 3nm 보다 얇아질 때 SS는 증가한다. 게이트 절연체는 고유전율 물질을 사용하는 것이 적절하다.

• Journal of Species Research
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• 제12권3호
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• pp.240-243
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• 2023

The genus and species, Diekeana insignis(Gorham), is reported for the first time in Korea. Male adults were collected from Geoje Island and Changwon-si, located in the southern part of South Korea. The species of D. insignis(Gorham) is characterized by the following morphological characteristics: body length about 9.4mm; pronotum with transverse black marking in the middle part; each elytron with seven large black markings; penis long, slightly bent at apical part, truncate at apex; parameres narrow and as long as penis guide; penis guide narrow and pointed at apex. We herein provide habitus photographs, illustrations of morphological characters, male genitalia, and a detailed diagnosis. A partial sequence of the mitochondrial COI gene was obtained and provided mtDNA information for this species.

• 수산해양기술연구
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• 제50권3호
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• pp.396-406
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• 2014

Shrimp beam trawl fishery is one of the important coastal fisheries in Korea. It has a regulation to the length of beam (8m) and wing net (7m) of shrimp beam trawl that has been used in the district of Junlanam-do and Gyungsangnam-do. This regulation was made in relation to the size of shrimp beam trawler of 3-ton class at that time. Now the shrimp beam fishing vessel has a limit not greater than 5 tons in gross ton. Recently, with improvement of fishing industry and fishing vessel fishermen asked the expansion of the length of beam and wing net, therefore it is necessary to investigate the effect of lengthening the beam and wing net length. Three different beams (8m, 10m and 12m in length) and three different wing net (7m, 10m and 13m in length) were made and the experiment was conducted near Narodo of Goheng by two fishing vessels of 4.98 and 4.88 tons in gross ton between June 2011 and October 2012. When the length of wing net was increased from 7m to 10m and 13m, the relative catch ratio in total biomass was increased 25% and 79% for shrimp, (17% and 22% in total), respectively. And when the beam length was increased from 8m to 10m and 12m, the relative catch ratio was increased 35% and 84% for shrimp, (21% and 37% in total), respectively. The force exerted to the iron guide of inhauler's with the beam length of 8m was about 30% greater than that with the beam length of 10m when hauling the shrimp beam trawl net.

• 한국항공우주학회지
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• 제32권8호
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• pp.72-81
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• 2004

초고속 지상 운행체에 대한 풍동실험을 통하여 단단한 채널과 운행체 사이에 발생하는 공력 상호작용을 연구하였다. 풍동실험시 유속은 30m/see에서, 단위길이당 레이놀즈수는 $3.1{\times}10^5/m$였다. 가변지면과 안내로와 같은 실험장치들이 이 실험을 위해 사용되었다. 운행체는 지면과 운행체 사이의 거리가 가까워질수록, 안내로 사이의 간격이 좁아질수록 양력은 급격히 증가하였고, 항력은 미세하게 감소하였으며, 키놀이 모멘트는 억제되어 정안 정성을 증대시켰다. 연선을 사용한 유동가시화를 통하여 운행체가 채널 내를 운행할 때의 유동 특성을 채널이 없는 경우와 비교하였고 공력측정 결과를 뒷받침하였다. 채널 지연과 안내로의 영향으로, 운행체 하부에서의 유동은 날개의 익단판 외부로 흐르지 못하며, 이것이 운행체 양력증가의 주요 원인이 되었다.

• 한국정밀공학회지
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• 제21권1호
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• pp.140-148
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• 2004

A novel rapid prototyping (RP) process, a full-automated transfer type variable lamination manufacturing process (Full-automated VLM-ST) has been developed. In the full-automated VLM-ST process, a vacuum chuck and a rectilinear motion system transfer the EPS foam material in the form of the plate with two pilot holes to the rotary supporting stage. The supplied material is then cut into an automated unit shape layer (AUSL) with a desired width, a desired length, a desired slope on the side surface, and a pair of reference shapes, which is called the guide shape (GS)’, including two pilot holes in accordance with CAD data through cutting in two steps using a four-axis synchronized hotwire cutter. Then, each AUSL is stacked by setting each AUSL with two pilot holes in the building plate with two pilot pins, and subsequently, adhesive is applied onto the top surface of the stacked AUSL by a bonding roller and pressure is simultaneously given to the bottom surface of the stacked AUSL. Finally, three-dimensional shapes are rapidly and automatically fabricated. This paper describes the method to generate guide shapes in AUSL data for the full-automated VLM-ST process. In order to examine the applicability of the method to generate guide shapes, three-dimensional shapes, such as a piston shape and a human head shape, are fabricated from the full-automated VLM-ST apparatus.

• 한국실내디자인학회논문집
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• 제20권5호
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• pp.152-159
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• 2011

Housing construction companies have been providing master bedroom walk-in closet as a selling point in modest sized apartments as small as 74m$^2$. It is noticeable that master bedroom walk-in closet in apartments provided by public sectors showed much variety in its size. This study tries to set up the guide line of master bedroom walk-in closet size. It is quite reasonable to assume that the biggest space-occupiers in walk-in closet are blankets and clothing. The survey conducted in this study shows that the number of clothes people keep in their closet does not show any significant difference regardless of square footage of their apartments. 34.7% of respondent answered they keep about 50-60 clothes using coat hangers, where 20-30 of those are winter clothes. It is calculated the required optimum length of the walk-in closet is 3.8m$^2$. Considering the most popular longitudinal dimension of master bedroom, 3.9m, and the space needed to accommodate blankets, it can be concluded that the required length of storage in master bedroom walk-in closet is 2.1m. The length can be adjusted reflecting the length of the master bedroom.