• 한국광학회지
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• 제25권6호
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• pp.301-310
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• 2014

현재 Fringe-field switching(FFS) 액정 모드는 고화질 및 고정세 액정 디스플레이에 주로 적용되고 있다. 본 총설에서는 FFS모드의 어떠한 동작원리가 기존에 다른 액정모드 보다 왜 우수한 전기광학 특성을 갖는지에 대한 상세 한 설명과 더불어 FFS모드의 역사적 발전 현황, 기술의 현 주 이슈 및 향후 발전방향을 기술한다.

• 한국초전도ㆍ저온공학회논문지
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• 제15권4호
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• pp.53-58
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• 2013

KSTAR in-vessel cryo-pump has been installed in the vacuum vessel top and bottom side with up-down symmetry for the better plasma density control in the D-shape H-mode. The cryogenic helium lines of the in-vessel cryo-pump are located at the vertical positions from the vacuum vessel torus center 2,000 mm. The inductive electrical potential has been optimized to reduce risk of electrical breakdown during plasma disruption. In-vessel cryo-pump consists of three parts of coaxial circular shape components; cryo-panel, thermal shield and particle shield. The cryo-panel is cooled down to below 4.5 K. The cryo-panel and thermal shields were made by Inconel 625 tube for higher mechanical strength. The thermal shields and their cooling tubes were annealed in air environment to improve the thermal radiation emissivity on the surface. Surface of cryo-panel was electro-polished to minimize the thermal radiation heat load. The in-vessel cryo-pump was pre-assembled on a test bed in 180 degree segment base. The leak test was carried out after the thermal shock between room temperature to $LN_2$ one before installing them into vacuum vessel. Two segments were welded together in the vacuum vessel and final leak test was performed after the thermal shock. Commissioning of the in-vessel cryo-pump was carried out using a temporary liquid helium supply system.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.3-4
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• 2006

Natural DNAs in dry state, i.e., A-DNAs, when intercalated with low levels of stable organic free radicals or complexed with low levels of Au(III), are attracted at room temperature to commercial magnets, whereas those containing high levels of intercalators or Au(III) are not. This surprising observation is explained by the EPR spectra and SQUID measurement of magnetization of the modified DNAs. It is conjectured that A-DNAs are morphologically heterogeneous containing ordered and disordered regions. The ordered regions appear to strongly mediate magnetic interactions between spins through their ${\pi}_z$-stacked structures. When the modified DNAs are wet or hydrated, they behave diamagnetically.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2009년 추계학술발표대회
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• pp.51-51
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• 2009

In order to understand the properties of high heat input welds made by electro gas welding, two kinds of low temperature steel were welded. Welding heat inputs were controlled by width of root gap and ranged from 118 to 143kJ/cm. Chemical composition and micro-structural analysis were performed. To understand low temperature impact properties, Charpy impact test was conducted at several temperatures. The results were summarized as follows; 1) Grain size of weld metal and heat affected zone was increased with an increase in welding heat input. 2) Impact test values at fusion line were severely fluctuated regardless of base metals, showing enormous difference among the values at the same test temperature.

• 한국가스학회:학술대회논문집
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• 한국가스학회 2004년도 추계학술발표회 논문집
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• pp.113-118
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• 2004

• 한국가스학회:학술대회논문집
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• 한국가스학회 2005년도 추계학술발표회 논문집
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• pp.44-48
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• 2005

• 한국가축번식학회지
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• 제19권3호
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• pp.171-179
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• 1995

This study was carried out to investigate the fertilizing ability of round spematids isolated from seminiferous tubules. A round spermatid was introduced into the perivitelline space of a mature oocyte using Leitz micromanipulators and then subjected to electrofusion. Electrofusion was induced by applying a single DC pulse of 90V with a duration of 60$\mu$sec using Model 611 Square Wave Stimulator(Phipps and Bird, U.S.A) in 0.3 M sucrose fusion medium containing 0.05mM CaCl2 and 0.1mM MgSO4, Oocyte pre-activation was conducted by exposure to a single DC(80V, 80$\mu$sec) pulse in electrofusion medium at 1 hour before electrofusion. The incidence of fusion with pre-activated oocytes(23.8%, 57/239) was higher than that with nonactivated oocytes(6.7%, 3/45). The most of electro-stimulated mouse oocytes cleaved regardless of the success or failure of fusion. Karyotyping of embryos that developed into blastocysts after exposure to the fusion pulse were performe. We found that blastocysts from the fused oocytes were diploid whereas blastocysts from the unfused oocytes were haploid. About 11.7 and 11.5% of fused and unfused oocytes were developmental potentials of fused and unfused oocytes. Therefore, these results suggest that the mouse mture oocyte can be fertilized by fusion with a round spermtid and subsequently developed normally.

• 폴리머
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• 제33권5호
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• pp.496-500
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• 2009

광학 보상 휨 액정디스플레이(OCB-LCD)는 빠른 응답속도와 광 시야각 특성 때문에 응용 분야가 많다. 하지만 OCB-LCD는 초기에 splay 상태로 배열되어 있고 계조 구동은 bend 상태에서 이루어지기 때문에 초기 splay 상태에서 bend 상태로의 빠른 전이가 필요하다. 기존에 순간적으로 고전압을 인가하는 방식과 달리 본 연구에서는 임계 전압과 광경화성 반응성 단량체의 고분자화를 통한 표면 선경사각 형성으로 초기 상태부터 bend 상태를 갖는 OCB-LCD를 제조하였다. 제조된 액정 셀의 전기 광학적 및 전기적 특성을 분석한 결과 본 연구에서 제조된 셀은 기존 OCB 셀에 비해 고 선경사각으로 인한 고속응답 특성을 보여주었고 액정 단량체에 의해 형성된 배향막 위의 고분자 층 형성에 따른 잔류 DC 값은 0.1 V 보다 적었다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2010년도 춘계학술발표대회
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• pp.20.2-20.2
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• 2010

Recently inkjet printing technology has been developed in the areas of low cost fabrication in environmentally friendly manufacturing processes. Although inkjet printing requires the interdisciplinary researches including development of materials, manufacturing processes and printing equipment and peripherals, manufacturing a printhead is still core of inkjet technology. In this study, a piezoelectric driven DOD (drop on demand) inkjet printhead has been fabricated on three layers of the silicon wafer in MEMS Technology because of its chemical resistance to industrial inks, strong mechanical properties and dimensional accuracy to meet the drop volume uniformity in printed electronics and display industries. The flow passage, filter and nozzles are precisely etched on the layers of the silicon wafers and assembled through silicon fusion bonding without additional adhesives. The piezoelectric is screen-printed on the top the pressure chamber and the nozzle plate surface is treated with non-wetting coating for jetting fluids. Printheads with nozzle number of 16 to 256 have been developed to get the drop volume range from 5 pL to 80 pL in various industrial applications. Currently our printheads are successfully utilized to fabricating color-filters and PI alignment layers in LCD Flat Panel Display and legend marking for PCB in Samsung Electronics.

• 센서학회지
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• 제31권4호
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• pp.194-213
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• 2022

This study comprehensively reviewed four types of integrated-optic electric-field sensors based on titanium diffused lithium-niobate waveguides: symmetric and asymmetric Mach-Zehnder interferometers, 1×2 directional couplers, and Y-fed balanced-bridge Mach-Zehnder interferometers. First, we briefly explain the crystal properties and electro-optic effect of lithium niobate and the waveguide fabrication process. We theoretically analyzed the key parameters and operating principles of each sensor and antennas. We also describe and compare the design, simulation, implementation, and performance tests: dc and ac characteristics, frequency response, dynamic range, and sensitivity. The experimental results revealed that the sensitivity of the sensor based on the Y-fed balanced bridge Mach-Zehnder interferometer (YBB-MZI) was higher than that of the other types of sensors.