• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1978년도 제12차 학술대회연제 순서 및 초록
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• pp.7.1-7
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• 1978

후두의 Microsurgery는 육안으로 관찰할 수 없는 작은 병변을 그 초기에 발견하고 치료하는데 유익하며 이는 근년에 와서 Scale(1960), Kleinsasser(1964) 등에 의해 개발되었고 Saito 및 많은 임상가들에 의해 추시된 바 있으며, 노도 그의 경험 20여례에 대하여 상세한 보고를 하였다. 귀수술에 사용되는 zeiss 수술현미경의 대물 lens 위에 보조 lens를 장치하여 충분한 작동거리를 확보할 수 있으며, 나아가 fiber optics에 의한 suspeasion laryngoscope로써 시야를 밝게 할 수 있으며, 따라서 정확한 진단 및 세밀한 수술을 할 수 있다. 즉 점막상피내암, 후두점막질환, 성대 polyp, nodule및 cyst 등에 대한 현대적 진단과 치료법이기도 하다. 저자 등은 전남의대 부속병원 이비인후과를 내원한 후두질환 환자중 선택적으로 suspension laryngomicr-oscopy를 이용하여 진단 및 외과적 적출을 시행한 11례(성대 polyp; 4례, 유두종; 4례, 진성대 및 가성대의 web형성; 1례, 후두외상; 1례, 후두상피세포암: 1례)를 경험하였기에 우선 예보를 하는 바이며, 앞으로 지속해서 많은 경험증례를 분석검시하여 보고하겠다.

• The Korean Journal of Physiology
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• 제2권2호
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• pp.75-81
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• 1968

According to recent observations of Cohen et al. the patterns of vestibular eye movements of rabbits are different from those of cats. However, the causes of such difference of the reflex eye movements in these species are not wholly explained. While the accumulated data obtained from cats appear to be established, experimental evidences in rabbits are rather meager. The author had re-examined the reflex eye movements of rabbits and attempted to find a mechanism which causes such difference in the reflex eye movements between two species. In anesthesized rabbit, unilateral individual semicircular canal nerve was stimulated selectively with a fine insulated electrode which was inserted through a hole made on the corresponding osseous canal, under a dissecting microscope. When an individual canal nerve was stimulated, the reflex movements of both eyes were observed, photographed, and recorded kymographically. Extraocular muscles were also studied to find their morphological characteristics and to correlate them with the function of the muscles. 1. At the beginning of the stimulation, both eyes moved to a specific direction depending upon the canal stimulated, and such directional eye movements were sustained during the whole course of stimulation. Amplitude of the eye movement showed graded responses to the increasing frequency of the stimulus, reaching to the maximal response at 200-300 cps. 2. Stimulation of the unilateral horizontal canal nerve caused conjugate eye movements, which was also observed in cats and other species by other investigators. 3. Stimulation of the unilateral vertical canal nerve caused a pattern of non-conjugate eye movements, which are different from those observed in cats. Such different patterns of vestibular eye movements in two different species are ascribable to the functional difference of the inferior and superior oblique muscles.

• 로봇학회논문지
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• 제5권2호
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• pp.152-159
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• 2010

Finding a head of a person in a scene is very important for taking a well composed picture by a robot photographer because it depends on the position of the head. So in this paper, we propose a robust head tracking algorithm using a hybrid of an omega shape tracker and local binary pattern (LBP) AdaBoost face detector for the robot photographer to take a fine picture automatically. Face detection algorithms have good performance in terms of finding frontal faces, but it is not the same for rotated faces. In addition, when the face is occluded by a hat or hands, it has a hard time finding the face. In order to solve this problem, the omega shape tracker based on active shape model (ASM) is presented. The omega shape tracker is robust to occlusion and illuminationchange. However, whenthe environment is dynamic,such as when people move fast and when there is a complex background, its performance is unsatisfactory. Therefore, a method combining the face detection algorithm and the omega shape tracker by probabilistic method using histograms of oriented gradient (HOG) descriptor is proposed in this paper, in order to robustly find human head. A robot photographer was also implemented to abide by the 'rule of thirds' and to take photos when people smile.

• Applied Microscopy
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• 제23권2호
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• pp.97-106
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• 1993

This study was done to elucidate the electron microscopic characteristics of certain pathogenic fungi. Four Candida species, (C. albicans, C. tropicalis, C. parapsilosis and C. glabrate) and Cryptococcus neoformans were cultured for 3 days at $30^{\circ}C$ in the Sabouraud dextrose medium. After incubation, they were stored at $4^{\circ}C$ for 24hours. Fine structures were analyzed by morphometry, and Tukey's HSD test was used for statistics. On scanning electron microscopy C. albicans and C. neoformans were similar in size but different in shape, showing sphero-shape or ovalo-shape in C. neoformans. Surface of C. neoformans was coarse and spiny, but Candida species examined were uniformly smooth. In size, C. glabrata was the smallest among them. Budding scar as seen on the surface of Candida species by the number ranging from 1 to 7. Cryptococcus neoformans showed one or two budding scar. On transmission electron microscopy the cytoplasm of most yeast cells showed plentiful glycogen particles, mitochondria, peroxisomes and vacuoles. However, cell walls were different among four Candida species and Cryptococcus neoformans. The cell wall of Candida species consisted of fibrous layer, that was electron dense layer and transparent layer, in contrast to Cryptococcus neoformans consisted of electron dense layer with lamellar structure. This layer was two times thicker than that of Candida species. The outer layer of cell wall was of radiating pattern.

• 한국농공학회논문집
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• 제54권3호
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• pp.37-45
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• 2012

Recently, the livestock industry in Korea was heavily affected by the outbreak of official livestock diseases such as foot and mouse disease, high pathogenic avian influenza, swine influenza, and so on. It has been established that these diseases are being spread through direct contact, droplet and airborne transmission. Among these transmissions, airborne transmission is very complex in conducting field investigation due to the invisibility of the pathogens and unstable weather conditions. In this study, the airborne transmission was thoroughly investigated inside a pig house by conducting tracer gas ($CO_2$) experiment because experiment with real pathogen is limited and dangerous. This is possible as it can be assumed that the flow is similar pattern very fine particles and gas. In the experiment, the ventilation structure as well as the location of gas emission were varied. The $CO_2$ detection sensors were installed at 0.5 and 1.3 m height from the floor surface. The tracer gas level was measured every second. Results revealed that the direction of spread can be determined by the response time. Response time refers to the time to reach 150 ppm from the gas emission source at each measuring points. The location of the main flow as well as the gas emission was also found to be very important factor causing the spread.

• Journal of the Korean Wood Science and Technology
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• 제25권3호
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• pp.43-49
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• 1997

The lengths of fibers and vessel elements, vessel diameters, and ray spacings of tension and opposite woods in Quercus mongolica Fischer and their radial variations were examined. Crystallinity indices and crystallites orientations of tension, opposite and lateral woods were also investigated. The lengths of fibers and vessel elements, and ray spacings of tension wood were longer and denser than those of opposite wood, respectively. In the latewood, the vessels of tension wood had a little larger diameters than those of opposite wood. whereas the vessel diameters of earlywood were similar in both woods. With the exception of vessel diameters of earlywood, there were differences between tension and opposite woods in all anatomical characteristics examined. In the radial variation pattern, the fiber lengths of both woods increased markedly to about 15th annual ring and thereafter remained virtually constant. The vessel element lengths of earlywood in tension wood increased to certain annual ring and thereafter were stabilized, but opposite wood had a relatively constant trend from pith to bark. Those of late wood in both woods increased to certain annual ring and thereafter showed constant patterns. Vessel diameters appeared to show similar trend in both woods. Ray spacings decreased to about 15 annual ring and thereafter were stabilized in both woods. In the fine structures, tension wood had higher crystallinity index and better crystallites orientation than opposite and lateral woods.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.277.2-277.2
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• 2013

Petri dishes and glass slides have been widely used as general substrates for in vitro mammalian cell cultures due to their culture viability, optical transparency, experimental convenience, and relatively low cost. Despite the aforementioned benefit, however, the flat two-dimensional substrates exhibit limited capability in terms of realistically mimicking cellular polarization, intercellular interaction, and differentiation in the non-physiological culture environment. Here, we report a protocol of culturing embryonic rat hippocampal neurons on the electro-spun polymeric network and the results from examination of neuronal cell behavior and network formation on this culture platform. A combinatorial method of laser-scanning confocal fluorescence microscopy and live-cell imaging technique was employed to track axonal outgrowth and synaptic connectivity of the neuronal cells deposited on this model culture environment. The present microfiber-based scaffold supports the prolonged viability of three-dimensionally-formed neuronal networks and their microscopic geometric parameters (i.e., microfiber diameter) strongly influence the axonal outgrowth and synaptic connection pattern. These results implies that electro-spun fiber scaffolds with fine control over surface chemistry and nano/microscopic geometry may be used as an economic and general platform for three-dimensional mammalian culture systems, particularly, neuronal lineage and other network forming cell lines.

• 한국정보통신학회논문지
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• 제11권3호
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• pp.479-485
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• 2007

본 논문에서는 사실적인 질량-스프링 기반 옷감 모델의 애니메이션을 효율적이며 사실적으로 생성하기 위해 근사된 암시적 적분법을 계층적으로 적용하는 기법을 제안한다. 제안된 계층적 시뮬레이션 방법은 매우 많은 정점을 가진 메쉬(mesh)의 사실적인 움직임을 상호작용적으로 생성할 수 있다. 이 기법은 암시적 적분법을 근사하는 빠르고 안정적인 방법을 사용한다. 이 근사 기법은 효율적이기는 하지만 극도로 부정확하며 지나치게 댐핑(damping)이 많이 일어난다. 본 논문에 제안된 계층적 시뮬레이션 기법은 메쉬 구조를 다중 단계로 구성하여 옷감 모델의 사실적인 외형을 표현하도록 하며, 각각의 단계에 시뮬레이션을 적용할 때 현재 단계의 메쉬에 존재하는 일부 질점이 이전 단계의 시뮬레이션 결과를 따르도록 한다. 이러한 계층적 시뮬레이션 방법은 많은 수의 질점으로 구성된 옷감 모델의 사실적인 동작을 효율적으로 생성한다. 또한 계층적 기법은 옷감 모델에 사실적인 주름을 생성할 수 있도록 하며, 계층적 단계에 따라 스프링의 수축 저항을 제어할 수 있도록 하여 주름의 패턴도 쉽게 제어할 수 있도록 한다.

• International Journal of Stem Cells
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• 제7권2호
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• pp.108-117
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• 2014

Background and Objectives: Genomic imprinting is an inheritance phenomenon by which a subset of genes are expressed from one allele of two homologous chromosomes in a parent of origin-specific manner. Even though fine-tuned regulation of genomic imprinting process is essential for normal development, no other means are available to study genomic imprinting in human during embryonic development. In relation with this bottleneck, differentiation of human embryonic stem cells (hESCs) into specialized lineages may be considered as an alternative to mimic human development. Methods and Results: In this study, hESCs were differentiated into three lineage cell types to analyze temporal and spatial expression of imprinted genes. Of 19 imprinted genes examined, 15 imprinted genes showed similar transcriptional level among two hESC lines and two human induced pluripotent stem cell (hiPSC) lines. Expressional patterns of most imprinted genes were varied in progenitors and fully differentiated cells which were derived from hESCs. Also, no consistence was observed in the expression pattern of imprinted genes within an imprinting domain during in vitro differentiation of hESCs into three lineage cell types. Conclusions: Transcriptional expression of imprinted genes is regulated in a cell type- specific manner in hESCs during in vitro differentiation.

• 농업생명과학연구
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• 제45권6호
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• pp.21-32
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• 2011

본 연구는 20세기 초기의 서양 흔들의자를 분석하여 조형적, 실용적 관점에서 양식적 특징을 학문적으로 규명하고, 오늘날 우리나라 흔들의자의 설계 및 제작의 기초자료를 제공하는 것에 목적이 있다. 20세기 전반의 서양 흔들의자(1925~1945년 제작)는 형태가 기능을 따라야 한다는 단순한 기능주의의 이념을 적극적으로 표현하였다. 원목을 활용한 흔들의자는 표면장식을 배제하였고, 강철관 프레임의 흔들의자는 검정색 가죽의 업홀스터리를 즐겨 사용하면서 노출된 구조미를 대담하게 표현하였다. 또 강철관을 통하여 가구의 경량화가 이루어졌고 곡선미 있는 새로운 양식이 출현하였다. 근대 흔들의자의 구조는 양식과 기능적 이유에서 모두 중요하게 되었다. 디자이너들은 강철관과 목재 프레임의 노출된 구조를 통합성 및 합리성과 결부 시켜 디자인의 평등주의 스타일을 만들어냈다. 특히 이 시기에는 밝고 대담한 색상의 업홀스터리와 목재 프레임으로 구성된 흔들의자가 근대적 특징의 단순한 형태로 다양하게 표현되었다.