• 제목/요약/키워드: V shape

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Applications of Extracellular Polysaccharide p-m10356

  • Park, Hee-Jung;Kim, Hyong-Ju;Lee, Chang-Moon;Kim, Jin;Lee, Hong-Kum;Yim, Joung-Han;Lee, Ki-Young
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2005년도 생물공학의 동향(XVI)
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    • pp.566-569
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    • 2005
  • tyrosinase 저해 활성 실험 결과 1.2%(w/v) 이상의 농도에서 70% 이상의 저해를 나타내 색소침착에 대한 기능성 화장품 원료로 사용이 가능할 것으로 보이며, ACE 저해 활성 실험에서 1.5% 농도에서 60% 가량의 저해활성을 보여 혈관 변형 치료 및 예방에 효과가 있을 것으로 기대된다. UV 흡수능에서는 UV-B, UV-C의 영역에서 흡수 경향을 나타내며 자외선 차단제의 원료로 사용이 가능할 것으로 기대되며, 또한 bead 형성능을 가지고 있어 약물전달체로서 이용 가능성이 기대된다.

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근접장현미경을 이용한 폴리머박막 나노리쏘그라피 공정의 특성분석 (Characteristics of Nanolithography Process on Polymer Thin-film using Near-field Scanning Optical Microscope)

  • 권상진;김필규;장원석;정성호
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.590-595
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    • 2004
  • The shape and size variations of the nanopatterns produced on a positive photoresist using a near-field scanning optical microscope(NSOM) are investigated with respect to the process variables. A cantilever type nanoprobe having a 100nm aperture at the apex of the pyramidal tip is used with the NSOM and a He-Cd laser at a wavelength of 442nm as the illumination source. Patterning characteristics are examined for different laser beam power at the entrance side of the aperture( $P_{in}$ ), scan speed of the piezo stage(V), repeated scanning over the same pattern, and operation modes of the NSOM(DC and AC modes). The pattern size remained almost the same for equal linear energy density. Pattern size decreased for lower laser beam power and greater scan speed, leading to a minimum pattern width of around 50nm at $P_{in}$ =1.2$\mu$W and V=12$\mu$m/. Direct writing of an arbitrary pattern with a line width of about 150nm was demonstrated to verify the feasibility of this technique for nanomask fabrication. Application on high-density data storage using azopolymer is discussed at the end.

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유한요소법을 이용한 V형상 극변환 메모리 모터의 특성 분석 (Characteristics Analysis of V Shape Pole Changing Memory Motor using Finite Element Method)

  • 김영현;김수용;김정우;이중호
    • 전기학회논문지
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    • 제64권6호
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    • pp.872-877
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    • 2015
  • The Permanent Magnet (PM) machine used at speed control using field-weakening control method. But the field-weakening current, which reduces the field flux for high speeds, causes significant copper and core losses. Therefore, this paper deals with the PM performance evaluations in a pole changing memory motor (PCMM). The PCMM can change the number of magnetic poles and produce two types of torque. When the motor operates with eight poles, it produces a magnetic torque at low rotational speeds. When the motor changes to four poles, it produces both magnetic torque and reluctance torque at high speeds. The paper explain the principle and basic characteristics of the motor by using a finite element method magnetic-field analysis, which consists of a PM magnetized by a pulse d-axis current of the armature winding. The results of our experiment show that the proposed motor reduces core loss by 10% and 55% under no-load and load conditions, and doubles the speed range of the motor.

액체금속 이온 소오스의 모양과 안정도에 대한 전자유체역학적 연구 (Electrohydrodynamic Treatment of the Shape and Stability of Liquid Metal Ion Sources)

고음질 합성방식용 V/UV 스펙트럼상의 피치변경법에 관한 연구 (On a Pitch Alteration Technique in the V/UV Spectrum for High Quality Speech Synthesis Technique)

  • 조왕래;배명진;김동성
    • 한국음향학회지
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    • 제15권6호
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    • pp.99-103
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    • 1996
  • 파형부호화법은 파형의 잉여성분 제거과정을 통해 음성파형의 꼴을 단순히 보존하는 부호화법이다. 음성합성분야에서 파형부호화법은 주로 분석에 의한 고음질 합성방식으로 적용되고 있다. 그렇지만 이 부호화법은 분석시에 여기원과 성도여파기 피라미터들로 분류하여 처리하지 않기 때문에 규칙에 의한 합성방식으로는 적용하기가 힘들다. 본 논문에서는 스펙트럼영역에서 유성스펙트럼에 대해서만 스펙트럼축의 변경을 통해 피치를 조절하는 새로운 피치변경법을 제안하였다. 이 방법은 주파수영역의 처리법이며 50%의 피치변경을 수행하여도 스펙트럼 왜곡율이 2.7% 이하로 얻어졌고, 시간영역의 위상특성 보상에 의해 프레임간의 진폭연결이 자연스럽다는 장점을 갖느다.

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Analysis of highway reflection noise reduction using transparent noise barrier types

  • Lee, Jaiyeop;Kim, Ilho;Chang, Seoil
    • Environmental Engineering Research
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    • 제20권4호
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    • pp.383-391
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    • 2015
  • Transparent type noise barrier is a desirable facility since it provides a secure view to drivers and passengers. However, reflection from this type of barrier could annoy dwellers on the sides of the road. To reduce reflection noise by transparent type barrier, modification can be made to the shapes on the front side and hence get effects by distortion of sound transmission. To achieve this, we have conducted simulation by which the effects of patterned screens of noise barrier on high-ways were investigated. The reduction effects of reflected sounds were evaluated for swelling, swelling with curved, rectangular and V-shaped screen type barriers, compared to the planar panel. The emitting noise was generated by 6-lane road and the patterned noise barriers had shown the reduction effects, especially in swelling and swelling with curved type for middle height dwellers, and the V-shaped screen type for higher elevation dweller. The swelling-type showed a decrease of 0.7~1.2 dB, performing the best diminution effect among the tested noise barriers.

비정질 Sb-Bi-Te 박막의 전기적 특성에 관한 연구 (A Study on the Electrical Properties of Amorphous Sb-Bi-Te Thin Films)

  • 이준신;이재형
    • 한국전기전자재료학회논문지
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    • 제15권3호
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    • pp.220-226
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    • 2002
  • Amorphous $Sb_{2-x}Bi_xTe_3$ (x = 0.0, 0.5 and 1.0) thin films were prepared by vacuum evaporation. The resistivity of 7he films decreases from 1.4{\times}10^{-2}$ to $8.84{\times}10^{-5}\Omega cm$ and the type of conductivity changes from p to n with the increase of the x value of the films. D.C. conduction studies on these films ate performed at various electric fields in the temperature range of 303-403 K. At low electric fields, two types of conduction mechanisms, i.e. the variable range hopping and the phonon assisted hopping are found to be responsible for the conduction, depending upon the temperature. The activation energy decreases from 0.082 to 0.076 eV in the temperature range of 303-363 K and from 0.47-0.456 eV in the second range of 363-403 K, indicating the shift of the Fermi level towards the conduction band edge and hence the change of the conduction from P to n type with the increase of the Bi concentration. Poole-Frankel emission dominates at high fields. The shape of the potential well of the localized centre is deduced and the mean free path of the charge carriers is also calculated.

Pyridinealdoxime 기능기 그룹을 가진 덴드리틱 거대분자를 이용한 LB막의 전기적 특성 (Electrical Properties of LB Films Using Dendritic Macromolecules Containing Pyridinealdoxime Functional Group)

  • 정상범;유승엽;박은미;김정균;박재철;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.761-763
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    • 2001
  • Dendrimers represent a new class of synthetic macromolecules characterized by a regularly branched treelike structure. Dendrimer can be made with high regularity and controlled molecular weight. Peculiar features of the dendritic geometry are the large number of end groups as well as the shape persistence in higher generations, approaching spherical geometry. One of the most peculiar characteristics of dendritic macromolecules is their controlled molecular structure and orientation, which means that they have a practical application in achieving a highly organized molecular arrangement. We attempted to fabricate a G4-48PyA dendrimer LB films containing 48 pyridinealdoxime functional end group that could form a complex structure with metal ions. Also, we investigated the surface activity of dendrimer films at air-water interface. And we have studied the electrical properties of the ultra-thin dendrimer LB films. The electrical properties of the ultra-thin dendrimer LB films were investigated by studying the current-voltage(I-V) characteristics of metal/dendrimer LB films/metal (MIM) structure. And rectifying behavior of the devices was occurred in applied field.

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DIURNAL HEATING IN THE OKHOTSK SEA UNDER ANTICYCLONIC CONDITIONS: MULTISENSOR STUDY

  • Mitnik, Leonid;Alexanin, Anatoly;Mitnik, Maia;Alexanina, Marina
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.1027-1030
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    • 2006
  • Development of diurnal warming in the open Okhotsk Sea during the daytime and calm conditions was studied using sea surface temperature (SST) fields retrieved from NOAA AVHRR, Terra and Aqua MODIS, Aqua AMSR-E and ADEOS-II AMSR data. Sea surface wind fields were estimated from AMSR-E/AMSR measurements as well as were obtained from QuikSCAT scatterometer. Weak winds and cloudless conditions were observed in the central area of anticyclone, which moved slowly on 28-30 June 2003 east off Sakhalin. The area where the amplitude of the diurnal SST signal ${\Delta}T$ was significant also shifted slowly and had or circular or elongated shape. The ${\Delta}T$ was estimated relative to the SST values in the areas surrounding the centre of anticyclone where wind speed W exceeded 5- 6 m/s. The diurnal variations of SST, day-night differences were computed using NOAA-12 and NOAA-16 AVHRRderived data. Analysis of simultaneous SST and W fields showed that the increase of W from 0 to 5-6 m/s causes the decrease of ${\Delta}T$ to zero. Maximum warming exceeded $8^{\circ}C$ and was observed in the centre of anticyclone where W = 0 m/s. So strong heating was likely due to the increased chlorophyll a concentration in the area under study that follows from analysis of satellite ocean colour data.

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KOH 용액 및 KOH-IPA 혼합용액에 의한 단결정 실리콘의 이방성식각 특성 (Anisotropic etching characteristics of single crystal silicon by KOH and KOH-IPA solutions)

  • 조남인;천인호
    • 한국진공학회지
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    • 제11권4호
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    • pp.249-255
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    • 2002
  • 이방성 습식 식각기술을 이용하여 멤버레인을 제작하기 위하여 KOH 용액 및 KOH-IPA 혼합용액을 사용하여 단결정 실리콘 기판을 식각하였다. 단결정 실리콘의 식각속도는 식각 용액의 온도와 농도에 좌우되었으며, 식각 용액의 농도에 따라 식각 형태와 패턴 형성 방향이 달라짐도 관찰되었다. 식각을 위한 표면패턴은 실리콘웨이퍼의 primary flat에 $45^{\circ}$로 기울여 형성되었으며 KOH의 농도가 20 wt%로 유지되었을 때, 식각 용액의 온도 $80^{\circ}C$ 이상에서는 U-groove, $80^{\circ}C$ 이하의 온도에서는 V-groove 식각 형태가 형성되었다. 각 면에 대한 식각속도 차이에 의해서 생기는 hillock은 온도와 농도가 높아짐에 따라 현저하게 줄어들었다.