• Proceedings of the Optical Society of Korea Conference
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• 2000.08a
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• pp.84-85
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• 2000

굴절률이 외부보다 큰 원통(cylinder)이나 구(sphere)는 경계면에서의 빛의 전반사(total internal reflection)에 의해 손실이 매우 적은 high-Q 공진기가 될 수 있음이 잘 알려져 있다. 이때 발진되는 공명모드를 '속삭이는 회랑 모드(whispering gallery mode: WGM)'라고 하며, 색소가 첨가된 고체 구, 액체 방울, 액체 제트 등의 미소 공진기나 반도체 microdisk 등에서 구현되었다. 이러한 미소공진기는 일반적으로 완전한 구나 실린더의 형태로 만들어지는데, 이 경우 공진 모드를 analytic 하게 구할 수 있고 기하 광학적으로 비교적 간단히 이해할 수 있다. 하지만 최근 Nockel 등에 의해 공진기에 변형을 가한 경우 여러 가지 재미있는 현상이 일어날 수 있다는 것이 밝혀졌다$^{(1, 2)}$ (중략)

• Journal of the Society of Naval Architects of Korea
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• v.40 no.3
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• pp.1-8
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• 2003

For the experiment of the friction drag reduction by microbubble injection, a drag reduction water tunnel was specifically designed and made. Experimental apparatus and procedures were devised and developed for measuring the change of wall friction drag with microbubble injection. For fully-developed channel flows. the change of friction drag with important parameters of microbubble injection is investigated and the experimental data and results obtained are presented. The amount of friction drag reduction up to 25% is observed in the present study.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.3
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• pp.262-275
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• 2015

The treatment of areas demanding esthetic requirements, such as maxillary anterior teeth, should take into account the achievement of a healthy, harmonious to the surrounding tissue, and an attractive smile line. In this case report, smile line, soft tissue and hard tissue morphology, and the anatomy and proportion of the tooth, must be considered. In patients with unesthetic maxillary anterior ratio due to inadequate gingival contour and diastema caused by peg lateralis, it would be challenging to achieve an esthetic restoration by orthodontic treatment alone. In such case, after orthodontic treatment, dento-gingivo-facial compositional diagnosis and analysis, followed by gingivectomy and prosthodontic restoration is needed to improve the interdental mesial/distal, width/length ratio to achieve a satisfactory esthetic result. In addition, when improving the tooth proportion of peg lateralis by prosthodontic treatment, Porcelain laminate veneer (PLV), which results in less tooth structure loss, reproduction of similar shade to that of the proximal tooth and high transparency, is recommended. This case report demonstrates esthetic improvements by prosthodontic restoration through systematic diagnosis and treatment procedure in patients with unesthetic maxillary anterior proportion after orthodontic treatment due to peg lateralis by means of two female patients aged twenty years old.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.30 no.2
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• pp.53-58
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• 2021

The attractiveness of the gingiva is determined by its color, shape, and the shape and location of the boundary between the teeth and the gingival tissue. The standards beauty, balance, and health of the gingiva are all different, but the general public would agree that a coral pink gingiva is more beautiful than black or brown gingiva. Hence, one would be able to smile more confidently in public if he or she receives a gingival pigmentation removal surgery that changes the color of black or brown gums to a beautiful pink color with relative simplicity. The color of one's gingiva varies from pale pink to deep bluish purple, depending on many health components. The most prominent among these include the vascular supply, epithelial thickness, the degree of keratinization, and the presence of pigment in the epithelium. Melanin, carotene, reduced hemoglobulin, and oxyhemoglobulin are the main pigments contributing to the normal color of the oral mucosa. The health of one's gingival tissue are essential for an attractive smile. Excessive melanin deposits in the basal and early basal layers of the epithelium stored in the form of melanosomes frequently cause pigmentation. Although there are many different procedures to remove this pigmentation, the it was removed using the Er;YSGG laser. It is my wish that, through this case study, many people

• Journal of the Korean Geophysical Society
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• v.5 no.1
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• pp.63-71
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• 2002

The integral equation method is a powerful tool for electromagnetic numerical modeling. But the difficulty of this technique is the size of their linear equations, which demands excessive memory and calculation time to invert. This limitation of the integral equation method becomes critical in inverse problem. To overcome this limitation, a lot of approximation and series methods, such as conventional Born, modifed Born and extended Born, were developed. But all the methods need volume integration of Green tensor, which is very time consuming. In electromagnetic theory, Green tensor rapidly decreases as the distance between source and field cell increases. Therefore, the source cell which are far away from the field cell does not make an effect on the electric field of the field cell. Consequently, by ignoring the effect of Green tensor due to far away source cells, computing time for electromagnetic numerical modeling can be reduced dramatically. Comparisons of this new method against a full integral equation, extended Born approximation and series code show that the method is accurate enough much less time consuming.

• Cartoon and Animation Studies
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• s.33
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• pp.383-402
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• 2013

In this study, we apply the facial Facial Action Coding System for coding the muscular system anatomical approach facial expressions to be displayed in response to a change in sensitivity. To verify by applying the virtual character the Duchenne smile to the original. I extracted the Duchenne smile by inducing experiment of emotion (man 2, woman 2) and the movie theater department students trained for the experiment. Based on the expression that has been extracted, I collect the data of the facial muscles. Calculates the frequency of expression of the face and other parts of the body muscles around the mouth and lips, to be applied to the virtual character of the data. Orbicularis muscle to contract end of lips due to shrinkage of the Zygomatic Major is a upward movement, cheek goes up, the movement of the muscles, facial expressions appear the outer eyelid under the eye goes up with a look of smile. Muscle movement of large muscle and surrounding Zygomatic Major is observed together (AU9) muscles around the nose and (AU25, AU26, AU27) muscles around the mouth associated with openness. Duchen smile occurred in the form of Orbicularis Oculi and Zygomatic Major moves at the same time. Based on this, by separating the orbicularis muscle that is displayed in the form of laughter and sympathy to emotional feelings and viable large muscle by the will of the person, by applying to the character of the virtual, and expression of human I try to examine expression of the virtual character's ability to distinguish.

• The Journal of the Acoustical Society of Korea
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• v.17 no.5
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• pp.79-84
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• 1998

본 논문은 길이방향으로 조화함수 형태로 변화하는 단면적을 가진 원형단면의 탄성 막대에서 전파하는 비틂 탄성파의 전파속도에 대한 이론적 및 실험적 결과를 제시한다. 주 기적인 미소한 반경 변화를 섭동법에 의해 다루어 전파속도의 이론적 근사해를 구하였다. 그결과 전파속도는 반경 변화 폭의 제곱에 비례하는 양 만큼 감소하는 경향이 나타났다. 이 론적 경향을 검증하기 위한 실험은 자왜현상으로 비틂파를 전파시키고 나사면을 가진 탄성 도파관에서 전파속도를 측정하는 방법으로 행하였다.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.7
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• pp.52-58
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• 2000

최근 첨단 미세가공기술로 주목을 받고 있는 실리콘 마이크로머시닝 기술과 이를 기반으로 한 산업용 MEMS 개발현황을 소개한다. 전반부에서는 마이크로머시닝 기술의 종류를 소개하고 각각의 기술에 대해 기술근원, 미세가공원리와 기본 가공공정을 간략히 요약한 후 기전 집적형태의 마이크로머신과의 연계성을 고려한 시스템적인 측면에서의 기술특성을 상호 비교한다. 또한 가공의 양산성, 재현성, 조립성 측면에서 마이크로머시닝의 가공성을 조명함과 동시에 향후 발전방향을 전망한다.(중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.347-348
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• 2003

감돌고기 Pseudopuntungia nigra는 Mori(1935)에 의해 금강수계에서 채집한 표본을 근거로 하여 처음으로 기재ㆍ보고된 종으로 금강, 만경강, 웅천천에만 서식하는 한국 고유종으로써(전, 1997) 1998년에 환경부 멸종위기종으로 지정되었다. 본 종에 관한 연구로는 내전(1939)의 형태학적 특징에 관한 연구, 전(1977)의 분포, 식성 둥에 관한 연구와 심(1985)의 골격 구조에 관한 연구, 이 둥(1983)과 김과 심(1991)에 의한 염색체에 관한 연구가 있었다. (중략)

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.3
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• pp.1057-1062
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• 1991

본 연구에서는 형상을 미소하게 변화시켜 좌굴을 방지할 수 있는 최적 도움형 상을 설계하였고 타원형, 토리-구형도움의 가장 얕은 형태의 최적도움형상도 설계하였] 으며, 실제 적용예를 수치로 제시하였다. 또한 수압(hydrostatic pressure)을 받는 수조(reservoir)의 도움형상에 대해서도 직경 및 길이 변화에 따른 형상설계 결과를 제시하였다.