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Nanoporous Block Copolymer Micelle/Micelle Multilayer Films with Dual Optical Properties

  • Cho, Jin-Han;Hong, Jin-Kee;Char, Kook-Heon;Caruso, Frank
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.310-310
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    • 2006
  • We have demonstrated the formation of highly nanoporous films composed of two different BCMs through layer-by-layer (LbL) assembly on substrates. The films thus prepared showed tunable optical properties, with strong antireflective properties with light transmission above 99%. Considering the wide application areas of both LbL multilayers and block copolymer thin films, the approaches introduced in present study are likely to open up new possibilities for devices with multifunctional properties.

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Feedback control synthesis for a class of controlled petri nets time constraints

  • Park, Hyeok-Gi;Park, Hong-Seong;Kwon, Wook-Hyun
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10a
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    • pp.330-335
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    • 1993
  • This paper presents an efficient solution for a class of forbidden state problems by introducing a cyclic timed controlled marked graphs (TCMG's), a special class of timed controlled Petri nets (TCPN's) as a model of a class of discrete event systems (DES's). The state feedback control is synthesized, which is maximally permissive while guaranteeing the forbidden states will be avoided. The practical applications or tire theoretical results for an automated guided vehicle (ACV) coordination problem in a flexible manufacturing facility is illustrated.

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NIR Spectroscopic Observation of Ultra-Long GRB 111209A and The Early Afterglow

  • Lee, Sang-Yun;Im, Myungshin
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.2
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    • pp.63.1-63.1
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    • 2016
  • We observed Ultra-Long GRB 111209A using NASA's 3m InfraRed Telescope Facility (IRTF). The observation was started around 40 min later than T0 = 07:12:08 UT of Swift's BAT, lasted for 24 min. The spectrum was extracted using Spextool package. The NIR SEDs show power law distribution indicating afterglow emission from the GRB according to the fireball model with beta ~ 1.2. Also they do not show thermal emission component compared to the SED of "Christmas burst" GRB 101225A. Because there is no other NIR data with this observation epoch, this data can be compared only with TAROT-R band. It seems NIR data has the same flare which exists in R band as an optical flare.

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Steady states and dynamic behavior of an LDPE autoclave reactor

  • Lee, Jin-Suk;Chang, Kil-Sang;Kim, Jae-Yeon;Rhee, Hyun-Ku
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.813-818
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    • 1989
  • A two compartmented autoclave reactor for the polymerization of low density polyethylene is analyzed with respect to the effects of heat transfer and operation variables. Each compartment being considered as a completely mixed cell, two CSTRs model is proposed. The system shows various multiplicity features of steady state and periodic oscillatory motions. Heat removal efficiency and initiator supplement appear to have significant effect on the conversion of monomer with the temperature properly maintained, which should be taken into account in the reactor design.

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Calculation of the Force Constants of Heteronuclear Diatomic Molecules by Use One Center Function. Ⅱ. Cubic Force Constants (일점전개함수에 의한 Heteronuclear Diatomic Molecules의 Force Constants의 계산 II. Cubic Force Constants)

  • Kim Hojing;Kim Hie-Joon
    • Journal of the Korean Chemical Society
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    • v.16 no.5
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    • pp.261-264
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    • 1972
  • The cubic force constants of the binary hydrides, LiH, BeH, BH, CH, NH and OH are evaluated by use of the one center function of Bishop et. al. The results are reasonably good. The master formula suggested in the previous report of the present author is found relatively insensitive to the crudities of the wave function.

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Microwave Irradiation, A New Processing Method of Aconiti Tuber (마이크로파를 이용한 부자의 새로운 수치방법)

  • Yun-Choi, Hye-Sook;Yoo, Kyung-Sook;Lee, Sook-Youn;Lee, Youn-Hee;Kwak, Wie-Jong;Kim, Ki-Hyup
    • Korean Journal of Pharmacognosy
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    • v.21 no.4
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    • pp.284-289
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    • 1990
  • Crude Aconiti Tubers were irradiated with microwave for 5 or 10 min with or without $NaHCO_3$. Ten min-irradiation reduced the contents of aconitine and mesaconitine to the level of those of commercially available processed Aconiti tuber power which is prepared with the high pressure-high temperature technique. The contents of benzoylaconine of the 10 min-irradiated Aconiti tubers were also comparable to those of commerciallized processed Aconiti tuber powder. However, irradiation with 1% $NaHCO_3$ soln. resulted in the drastic reduction of all the three above alkaloids.

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Degradation in Steels: Transformation Plasticity

  • Cho, Yi-Gil;Han, Heung-Nam
    • Journal of the Korean Ceramic Society
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    • v.49 no.1
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    • pp.1-10
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    • 2012
  • Super-plastic deformation that originates from transformation plasticity has favorable aspects for steels with improved strength and ductility. However, it also causes undesirable deformation of products or specimens, leading to their degradation. This article reviews recent investigations of transformation plasticity. A combination of newly suggested models, numerical analyses, and novel experiments has attempted to reveal the mechanism. Since the nature of the transformation plasticity is still unclear, there are significant challenges still to be solved. Fundamental understanding of transformation plasticity will be essential for the development of advanced steels.

Currarino Triad

  • Lee, Ho-Jin;Kong, Min-Ho;Kim, Dong-Seok;Kim, Tae-Sung
    • Journal of Korean Neurosurgical Society
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    • v.37 no.1
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    • pp.63-66
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    • 2005
  • The authors report a case of Currarino triad which had a congenital anorectal stenosis associated with a sacral defect and a presacral mass. A 1-year-old female presented with constipation since birth. Neurological deficits were not found on admission. She had had a diverting colostomy due to anorectal stenosis at another hospital before admission. Lumbar X-ray films showed bony defect caudal to the third sacral vertebra. Magnetic resonance image demonstrated a round cystic pelvic mass which was connected with a dural sac via anterior sacral defect. Posterior approach with Intradural removal of the presacral cystic mass was performed and followed by anoplasty by a pediatric surgeon. The cystic mass was verified histologically as mature teratoma with cystic change. Postoperatively, the urinary function and bowel movement remained intact. Currarino triad should be suspected and evaluated physically and radiographically in a case of congenital anorectal stenosis. Prompt recognition and close cooperation between pediatric surgeons and neurosurgeons is advisable to ensure adequate surgical treatment.

Development of Expert System for Protection Coordination of Transmission Systems (송전계통 보호 협조 전문가 시스템의 개발)

  • Lee, Seung-Jae;Park, Young-Moon;Shim, Joung-Wook;Yoon, Sang-Hyun;Yoon, Man-Chul;Lee, Sang-Ok
    • Proceedings of the KIEE Conference
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    • 1990.07a
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    • pp.129-132
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    • 1990
  • This paper reports an expert system for coordination of protective relays in the high voltage transmission system. The proposed system consists of five modules and has adopted the frame and production rule representations achieving the efficient data storage and knowledgebases. It has an interface to the fault program PSS/E and has reduced the data retrival time by implementing the local database containg only the minimum information for the process. Different relay parameters and output formats of the setting results can be easily incorporated owing to the rule-based structure. Graphics-based output helps understanding of the process and enhances the practical power.

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A Hand Motion Tracking Algorithm using Motion Vectors in H.264/AVC Compression (H.264/AVC Motion Vector를 이용한 손 추적 알고리즘)

  • Yum, Joohyuk;Lee, Hyuk-Jae
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2011.11a
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    • pp.147-149
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    • 2011
  • 사용자에게 편리한 인터페이스를 제공하는 IT 기기가 널리 보급되면서 직관적인 인터페이스 기술에 대한 관심이 높아지고 있다. 이미지 센서로 입력된 사람의 손 모양이나 움직임을 이용하는 인터페이스가 그 중 하나이다. 한 편 이미지 센서 영상을 저장하기 위하여 H.264/AVC와 같은 영상 압축 기술이 사용된다. 영상을 압축하기 위해 부호기는 모든 Macroblock에서 움직임 추정을 수행한다. 추정된 움직임 정보는 손 움직임을 인식하는데 사용될 수 있고 이를 통해 전자 기기에 명령을 내리는 인터페이스 기술의 한 부분을 구현하는 것이 가능하다. 본 논문은 H.264/AVC 부호기의 Motion Vector를 이용하는 손 추적 알고리즘을 제시한다. 제시된 알고리즘은 손 움직임 추적의 정확도를 향상시키기 위하여 Motion Vector보다 신뢰도가 높은 Motion Density Map 정보를 사용한다. 이 정보를 이용하여 이동한 손을 포함하는 손 윈도우를 결정한다. 실험 결과를 통하여 제시된 알고리즘이 손의 움직임을 추적하는 것을 확인할 수 있다.

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