• 제목/요약/키워드: external cavity

검색결과 225건 처리시간 0.027초

Disintegrating Behavior of A Rapidly Disintegrating Famotidine Tablet Formulation

  • Park, Jeong-Sook;Shin, Kwang-Hyun;Park, Jong-Bum;Lee, Si-Beum;Hwang, Sung-Joo
    • Journal of Pharmaceutical Investigation
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    • 제37권5호
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    • pp.275-280
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    • 2007
  • A rapidly disintegration famotidine tablet formulation in the oral cavity was developed using microcrystalline cellulose (MCC) and low-substituted hydroxypropyl cellulose (L-HPC), or additionally cropovidone as an internal disintegrant. Effects of disintegrants on the disintegration time in vitro and hardness were evaluated. Average wetting time of the tablets prepared in scale-up manufacturing process was less than 15 sec. Among the formulations tested, the tablet prepared with crospovidone as an internal disintegrant and Emcocel $90M^{(R)}$ as an external disintegrant showed fastest disintegration. These results may suggest that crospovidone and Emcocel $90M^{(R)}$ possessed excellent wetting nature, which result in the rapid disintegration of tablet.

Mode Analysis and Modal Delay Measurement of a Few-Mode Fiber by Using Optical Frequency Domain Reflectometry

  • Ahn Tae-Jung;Moon Sucbei;Youk Youngchun;Jung Yongmin;Oh Kyunghwan;Kim Dug Young
    • Journal of the Optical Society of Korea
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    • 제9권2호
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    • pp.54-58
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    • 2005
  • A novel mode analysis method and differential mode delay measurement technique for a multimode optical fiber based on optical frequency domain reflectometry has been proposed for the first time. We have used a conventional OFDR with a tunable external cavity laser and a Michelson interferometer. A few-mode optical multimode fiber was prepared to test our proposed measurement technique. The differential mode delay (DMD) of the sample fiber was measured to be 16.58 ps/m with a resolution of 1.5 ps/m. We have also compared the OFDR measurement results with those obtained using a traditional time-domain measurement method.

^{87}Rb D_2$ 전이선에 대한 원편광 분광 연구 및 레이저 주파수 안정화 (Circular Polarization Spectroscopy in ^{87}Rb D_2$ line and Laser Frequency Stabilization)

  • 문한섭;김승일;김현아;김중복;이호성
    • 한국광학회지
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    • 제6권4호
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    • pp.317-323
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    • 1995
  • 선폭 축소된 반도체 레이저를 이용하여 루비듐 원자의 $D_{2}$ 전이선에 대해 도플러 효과가 제거된 편광분광을 실시하고 광펌핑 편광 분광 이론과 비교하였다. 펌프광이 충분히 약했을 때 실험에서 얻어진 분산모양의 스펙트럼은 단일 주기 광펌핑 이론과 잘 일치하였다. 또한 편광 분광 신호를 직접 오차신호로 사용하여 공진기 길이를 보상한 결과, 주파수 변조를 하지 않고서도 레이저 주파수를 원자의 초미세 전이선에 안정화시킬 수 있었다.

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Color and Luminance Compensation for Large AMOLEDs

  • Park, Kyong-Tae;Arkipov, Alexander;Lee, Baek-Woon;Kim, Seon-Min
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.850-853
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    • 2009
  • Many well-known pixel compensation circuits have been applied to control TFT $V_{th}$ variations on small size AMOLED panels. For large (>30-inch) AMOLEDs, luminance and color uniformity are affected by TFT variations, but also by ELVDD IR drop and cavity non-uniformity which are not easily compensated by in-pixel circuits. AMOLED panels may also suffer from manufacturing-induced mura. An external compensation method based on optical measurements is proposed and applied to large AMOLED panels. It improves luminance uniformity by up to 95% at 200nits and color uniformity by up to 99% (${\Delta}$u'v' <0.004) on large AMOLED panels, and provides-increased margin against processinduced mura.

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Saturated Absorption Spectroscopy of 13C2H2 in the Near Infrared Region

  • Moon, H. S.;Lee, W. K.;Suh, H. S.
    • Journal of the Optical Society of Korea
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    • 제8권1호
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    • pp.1-5
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    • 2004
  • Using the external cavity spectroscopy method, we have observed the saturated absorption spectrum of the P(16) line of the v$_1$+v$_3$ band of $^{13}C$_2$H$_2$$. The frequency of a laser has been stabilized to the saturated absorption spectrum. The relative contrast of the saturation spectrum is about 7% with respect to the linear absorption and the linewidth is about 1.8 MHz. The frequency fluctuation of the stabilized LD is about $\pm$ 20 KHz for a sampling time of 100 ms.

설압력 측정품구에 관한 연구 (A STUDY OF ELECTRONIC DEVICE FOR THE MEASURING THE TONGUE PRESSURE)

  • 이호용;김기환;정경훈
    • 대한치과의사협회지
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    • 제15권12호
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    • pp.1027-1030
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    • 1977
  • It has been widely believed that the exact measurement of the forces exerted on teeth and its structures by the lingual and perioral musculatures such as lip, cheek and tongue is important and significant in dentistry. Such measuring, moreover, is highly emphasized the importance of the fact that it can be of much help to study the physiological function displayed in the oral cavity. Recognizing the importance of measuring the pressures, the author has devised an electronic device consisting of pressure transducers utilizing reistance-strnain gauges. This electronic strain gauge was very easy to manipulate and its scale error was extremely minimized, unaffected by mouth temperature, mosture and external forces Author was able to read its results with attached meter without using calibration chart. Futhermore, the sensitivity of this electronic device was extremely high, Thus it facilitated to measure a force from 0 to 230 grams.

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고온용 태양열 복합 흡수기의 열특성 분석 연구 (A Study on Thermal Characteristics of Hybrid Solar Receiver for Dish Concentrating System)

  • 강명철;김진수;강용혁;김낙주;유성연
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 춘계학술대회
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    • pp.571-575
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    • 2006
  • To improve economic of solar power generation, stirling engine is required continuous operation and the receiver has to be provided with an additional combustion system. The hybrid receiver with a specially adapted combustion system is possible to 24 hr/day operation by solar and gas-fired. The inner cavity and external wall serve as absorber surfaces using collected irradiation and heat transfer surfaces for the gas heat flow, respectively. The hybrid receiver was designed and fabricated for the dish/stirling system. The analytical method for pridicting natural convective heat loss from receiver is used. The Koenig and Marvin model is used to estimate convection heat loss and heat transfer coefficiency.

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Comprehensive understanding of vascular anatomy for endovascular treatment of intractable oronasal bleeding

  • Moon, Sungjun
    • Journal of Yeungnam Medical Science
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    • 제35권1호
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    • pp.7-16
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    • 2018
  • Oronasal bleeding that continues despite oronasal packs or recurs after removal of the oronasal packs is referred to as intractable oronasal bleeding, which is refractory to conventional treatments. Severe craniofacial injury or tumor in the nasal or paranasal cavity may cause intractable oronasal bleeding. These intractable cases are subsequently treated with surgical ligation or endovascular embolization of the bleeding arteries. While endovascular embolization has several merits compared to surgical ligation, the procedure needs attention because severe complications such as visual disturbance or cerebral infarction can occur. Therefore, comprehensive understanding of the head and neck vascular anatomy is essential for a more effective and safer endovascular treatment of intractable oronasal bleeding.

귀에 발생한 가성낭종의 수술 후 실리콘 자석 압박 치료 사례 1예 (A Case of Postoperative Silicone Magnet Compression Treatment of Pseudocyst in the Ear)

  • 설성훈;정찬민;박명철
    • 대한두경부종양학회지
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    • 제38권1호
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    • pp.69-74
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    • 2022
  • Endochondral pseudocyst of the ear is a rare, benign, non-inflammatory cystic disease. It is known that there are a variety of treatment methods for pseudocyst, which is mainly common in the scaphoid or triangular fossa of the ear. Pseudocyst formation is prevalent in the residual cavity of the ear. So, to prevent a recurrence, a surgical approach is also required, but management through compression is necessary after surgery. Applying a cube magnet to the lesion to press provides patient convenience and facilitates continuous management.

외부로 휜이 있는 수직이중관내의 조합대류 유동에 관한 수치적 연구 (Numerical Analysis on Combined Convection for a Vertical Cocentric Cylinder with External Fins)

  • 손상석;이채문;임장순
    • 대한설비공학회지:설비저널
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    • 제14권2호
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    • pp.118-124
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    • 1985
  • The motion of a fluid in the closed annular cavity formed by two concentric vertical cylinders with externally finned tube has been analysed by a numerical solutions of the equation of momentum and energy. For the calculation procedure, the fluid is assumed to have constant thermo-dynamic and transporties except for the density, which is temperature-dependent in the buoyancy term of the vertical momentum equation (Boussinesq approximation). The govern ins equations for velocity and temperature are solved by a finite difference technique which incoorporates a scheme for treating the coupled variables. Results are presented for a range of the Rayleigh number and for various values of the fin height and the number of fins.

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