• Archives of Plastic Surgery
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• 제33권2호
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• pp.175-180
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• 2006

Preoperative angiography is frequently used in the planning of microsurgical reconstruction for identification of vascular abnormality that influence the planning of operation. But, recently 3D CT angiography is considered as new technique that can provide detailed information about vascular anatomy as well as soft and bony tissue without the risks of invasive angiography. 3D CT angiograms were performed in 19 patients before microsurgical reconstruction for the lower extremity and hand between May of 2003 and Oct of 2004. Sixteen of the studies were of the donor site and all of 19 studies were of the recipient site. No complications were found from the 3D CT angiograms. In one case of the bone exposed open wound, the injury of anterior tibial artery was identified and the zone of injury was adequately demonstrated. With the improvement in quality of CT imaging, 3D CT angiograms may provide a favorable alternative to invasive angiography. It is capable of providing high-resolution, three dimensional vascular imaging without the need for arterial puncture and prolonged post-procedure observation. The relation among blood vessels, bones, and soft tissue is well demonstrated in 3D CT angiogram. Also The acquisition time and examination cost were considerably lower in comparison with invasive angiography. In conclusion, this study demonstrates that 3D CT angiography may provide accurate, safe, and cost-effective preoperative imaging. The 3D CT angiography with relatively low morbidity, low cost, ease of image acquisition can have an broader role in microsurgical reconstructive surgery.

• Journal of Chest Surgery
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• 제39권6호
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• pp.482-485
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• 2006

비디오흉강경수술은 조직에 손상을 덜 주고, 통증완화 및 미용효과가 우수하며, 환자의 회복이 빠른 장점이 있어 흉부외과 영역에 광범위하게 적용되고 있다. 그러나 2차원 평면이미지의 한계, 내시경기구들의 제한된 움직임 등의 단점이 있어 이를 극복하고자 많은 기술적 발전이 이루어져 왔으며, 이 중 현재 가장 앞선 것이 다빈치 수술로봇(da $Vinci^{TM}$ Surgical System)이다. 구미에서는 이미 많은 기관에서 다빈치 수술로봇을 이용한 수술이 시행되고 있으며, 국내에는 2005년 5월 연세대학교 의과대학 세브란스병원에 도입된 후 7월에 식품의약품안전청의 승인을 받아 수술에 이용되기 시작하였다. 저자들은 전종격동에 발생한 기형종에 대하여 다빈치 수술로봇을 이용한 종양적출술을 성공적으로 시행하였기에 보고하는 바이다.

• 천문학회보
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• 제43권1호
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• pp.42.4-43
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• 2018

Most galaxies are believed to evolve through mergers and accretions. In particular, minor mergers and gas accretion appear to play an important role in galaxy evolution in the present-day Universe. Tidally-disrupted debris from such processes remain as diffuse, low-surface brightness structures because the dynamical timescale in the outskirts is significantly longer than that in the central regions. Although these structures will give us useful insight into the mass assembly history of galaxies, it is difficult to detect them due to their faint surface brightness. In order to investigate the structural properties of outskirts in nearby galaxies, we conduct deep and wide-field imaging survey with KMTNet. We present our observing strategy and an optimal data reduction process to recover faint extended features in the images of KMTNet. Using the imaging data of NGC 1291 obtained from KMTNet, we find that a peak-to-peak sky gradient can be reduced less than 0.4-0.6% of the original sky level in the entire image. We also find that we can reach the surface brightness of ${\mu}_{(B,1{\sigma})}$ ~ 29.5, ${\mu}_{(R,1{\sigma})}$ ~ 28.5 mag $arcsec^{-2}$ in one-dimensional profile, that is mainly limited by the uncertainty in the sky determination. It indicates that deep imaging data of KMTNet is suitable to study the extended faint features of nearby galaxies, such as stellar halos, outer disks, and dwarf companions.

• 한국해양공학회지
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• 제32권4호
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• pp.287-295
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• 2018

This paper presents the results of an exploration of the ferromanganese crusts of Western Pacific Seamount registered by the Korean government. This area has been surveyed with a deep-sea camera and crust samples have been acquired by deep-sea dredging since 2013. On October 18-19, 2017, a united research team from KIOST and KRISO explored two blocks, OSM11 and OSM07, on the seamount using Hemire ROV. A precise survey was conducted on the ferromanganese crusts and sediments covering the slope/top of OSM11 and the middle flat area of OSM07. Rock samples were collected with precise positioning, and HD videos were recorded for 7 hours. This paper discusses the technical issues of this exploration in terms of (1) how to deal with an emergency situation during an electric power blackout, (2) the improvement of the thruster power by adding cooling plugs to the housings of the thruster amplifiers, (3) the relative motion of the depressor by changing the fixing method of the cable terminator, which affects the service life of the cable, (4) a sampling technique for the steep slope of the seamount, (5) integrated navigation under a USBL blackout, and (6) a 3-dimensional image mosaic for visualizing the distribution state of the crusts.

• 한국컴퓨터산업학회논문지
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• 제2권6호
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• pp.817-826
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• 2001

본 논문에서는 훼손된 신호를 처리하는 방법에 대해 연구하였다. 기존의 처리방법은 특이점이나 악 조건일 경우 수렴 속도가 늦어진다는 점과 처리시간이 많이 소요되는 단점이 있다. 이러한 단점을 보완하기 위하여 Gauss-Seidel 방법으로 처리하는 방법이 있으나 이러한 경우 신호를 반복해서 처리해야 하므로 처리시간이 많이 소요된다. 이러한 단점(수렴 속도, 전체 처리시간)을 개선하기 위하여 본 논문에서는 기존의 신호처리 (Tikhnov-Miller)와 제안된 알고리즘을 적용시켜 비교하여 봄으로써 특이점 혹은 악조건일 경우에도 수렴속도를 고속화하여 기존의 Tikhnov-Miller 신호 처리 방법보다 처리 시간을 단축할 수 있는 신호 처리 방법을 제시하였다. 제안된 최적화 알고리즘을 영상신호에 적용시켜 가속 상수에 따른 처리 신호에 대한 실험과 오차(mean-square error)의 변화를 비교하여 봄으로써 처리정도를 알아보았다. 그리고, 본 알고리즘의 유효성을 입증하기 위하여 모든 가속상수의 변화에 대한 신호처리 결과와 처리시간을 측정하였다.

• 한국지형공간정보학회:학술대회논문집
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• 한국지형공간정보학회 1995년도 학술발표회 개요집
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• pp.99-119
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• 1995

위성영상을 이용한 대부분의 연구는 대상지역에 대한 2장의 스테레오영상(stereo-pair)을 입체적으로 해석하여 3차원 위치를 결정하거나 영상 상판 기법을 적용한 입체매칭을 통하여 수치지형표고를 추출하였다. 그러나 스테레오 영상을 이용하여 위성의 위치 및 자세를 모델링하거나 위치정보를 얻고자 할 경우에는 기준점의 미세한 오차량에도 크게 영향을 받기 때문에 그 결과에 대한 안정성을 기대하기가 어려웠다. 또한 두 화상중 하나의 화상에 노이즈(noise), 그림자, 또는 구름이 존재할 때 그 지역에 대한 수치지형모델의 생성이 불가능하거나 정확도가 저하되는 것이 문제로 지적되어 왔다. 이러한 경우에 다중의 입체영상을 분석하므로써 문제점을 해결할 수 있으며 본 연구에서는 동일지역에 대한 3장의 SPOT 위성영상을 입체적으로 해석하여 수치지형 표고모델의 정확도를 개선하였다.

• 한국작물학회지
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• 제60권1호
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• pp.97-106
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• 2015

Platycodon grandiflorum, commonly known as Doraji in Korea, has a wide range of pharmacologic properties, such as reducing adiposity and hyperlipidemia, and antiatherosclerotic effects. However, the mechanisms underlying these effects remain unclear. In order to profile proteins from the nodal segment, callus, root and shoot, high throughput proteome approach was executed in the present study. Two dimensional gels stained with CBB, a total of 84 differential expressed proteins were confirmed out of 839 protein spots using image analysis by Progenesis SameSpot software. Out of total differential expressed spots, 58 differential expressed protein spots (${\geq}$ 2-fold) were analyzed using MASCOT search engine according to the similarity of sequences with previously characterized proteins along with the UniProt database. Out of 58 differential expressed protein, 32 protein spots were up-regulated such as ribulose-1,5-bisphosphate carboxylase, endoplasmic oxidoreductin-1, heat stress transcription factor A3, RNA pseudourine synthase 4, cysteine proteinase, GntR family transcriptional regulator, E3 xyloglucan 6-xylosyltransferase, while 26 differential protein spots were down-regulated such as L-ascorbate oxidase precursor, late embryogenesis abundant protein D-34, putative SCO1 protein, oxygen-evolving enhancer protein 3. However, frequency distribution of identified proteins using iProClass databases, and assignment by function based on gene ontology revealed that the identified proteins from the explants were mainly associated with the nucleic acid binding (17%), transferase activity (14%) and ion binding (12%). In that way, the exclusive protein profile may provide insight clues for better understanding the characteristics of proteins and metabolic activity in various explants of the economically important medicinal plant Platycodon grandiflorum.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.183-184
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• 2006

Some researchers proposed positive effects of whole body vibration (WBV) on osteoporotic trabecular bones of animals. In the present study, the correlation between the improvement of morphological characteristics and the effect of WBV was investigated and analyzed in OVX rats. The rats were randomly assigned to 5 groups: control, sham, WBV 17Hz, WBV 30Hz and WBV 45Hz. The WBV groups were exercised on a vibration platform (magnitude : $1mm_{peak-peak}$, frequency : 17Hz, 30Hz and 45Hz, 30 minutes/day for 5 days/week). The 4th lumbar on rats was scanned by In-vivo Micro-CT at the week 0(just before WBV) and the week 8(after WBV). Structural parameters of the 4th lumbar, based on two dimensional (2D) scan image data, were investigated and analyzed. The quantitative decrement rate of trabecular bone on WBV groups with 30Hz and 45Hz were lower than control and sham groups. The results showed the positive effect of WBV on osteoporotic bones of OVX rats.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.649-650
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• 2006

Some researchers proposed positive effects of whole body vibration (WBV) on osteoporotic trabecular bones of animals. In the present study, the correlation between the improvement of morphological characteristics and the effect of WBV was investigated and analyzed in OVX rats. The rats were randomly assigned to 5 groups: control, sham, WBV 17Hz, WBV 30Hz and WBV 45Hz. The WBV groups were exercised on a vibration platform (magnitude $1mm_{peak-peak}$, frequency : 17Hz, 30Hz and 45Hz, 30 minutes/day for 5 days/week). The 4th lumbar on rats was scanned by In-vivo Micro-CT at the week 0(iust before WBV) and the week 8(after WBV). Structural parameters of the 4th lumbar, based on two dimensional (2D) scan image data, were investigated and analyzed. The quantitative decrement rate of trabecular bone on WBV groups with 30Hz and 45Hz were lower than control and sham groups. The results showed the positive effect of WBV on osteoporotic bones of OVX rats.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.135-136
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• 2012

Carbon atoms near the surface of W(110) induce reconstructions such as $R(15{\times}12)$ -C/W(110) which consists of two characteristic parts, one square shaped and bright protrusion and two smaller ones. In the atomic resolution STM image, the bigger protrusion shows the periodicities of clean W(110), indicating that it is almost carbon poor region. The smaller protrusion contains hexagonal carbide surface layer of ${\alpha}$-W2C on W(110). Employing this carburized W(110) as templates, we grow Co and Fe clusters of less than ten atoms. Due to the selectivity of bonding sites, growth of larger cluster is highly unfavorable for Co and the size of clusters is very uniform. Since Co atoms prefer to sit on the bigger protrusion rather than smaller one, Co cluster can be arranged one-dimensionally in $R(15{\times}12)$-C/W(110) with quite uniform size distribution. However, Fe clusters sit on both sites without favored site, but still with uniform size distribution. On the other hand, Fe clusters can be grown with quasi one-dimensional order in $R(15{\times}3)$-C/W(110), which consists of only smaller protrusions. We investigate the magnetic properties of the ordered nano-sized clusters. Experiments using XMCD reveals little magnetic moment of Co cluster on $R(15{\times}12)$-C/W(110). This observation is consistent with the predictions of our first principles calculations that small Co clusters can be nonmagnetic or antiferromagnetic with low mean magnetic moment per atom.