• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.924-929
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• 2002

We have developed the novel liquid crystal materials with a difluoromethyleneoxy (CF2O) moiety as a linkage group in order to satisfy the diversified various requirements for AM-LCDs. These novel CF2O LC materials have excellent physical properties that are high dielectric anisotropy, low viscosity and wide nematic temperature ranges. Physical properties measurement results that mixtures containing CF2O LC materials have suitable for characteristics for AM-LCDs. The CF2O LC materials are excellent compound for quick response and low driving voltage application.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1593-1595
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• 2009

We demonstrate an intriguing liquid crystal display (LCD) mode that comprises an optically isotropic liquid crystal (LC) composite incorporating with inplane electric field geometry. No surface treatment, such as rubbing, is required to fabricate the LCD mode because it is based on an optically isotropic state. The measured response time was of submillisecond order. The LCD mode has several unique features such as fast response, continuous grayscale capability, and a high contrast ratio.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.534-537
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• 2007

To promote liquid crystal application of nanoimprint lithography, a polymer with new concept is proposed. The material consists of a polyamic acid for good LC alignment and an epoxy resin for good imprinting. The result of sum-frequency generation (SFG) vibrational spectroscopy proves that this material is a functionally gradient material. This material shows excellent capability as a nanoimprinting material as well as an LC alignment layer.

• Journal of Environmental Health Sciences
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• v.31 no.6
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• pp.451-456
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• 2005

Minamata disease made its first appearance in the world at Minamata City, Kumamoto Prefecture, in May 1956. In 1962 methyl mercury poisoning through the placenta was found for the first time in the world. This was called congenital Minamata disease. In all cases the clinical symptoms were consistent with those of cerebral palsy. The time and place of outbreak were the same as those for Minamata disease. Their mothers had eaten fish and shellfish during pregnancy. The principal symptoms of congenital Minamata disease are mentalretardation ($100\%$); primitive reflexes ($100\%$); disturbance of coordination ($100\%$); dysarthria ($100\%$); limb deformation (100%); growth disorders ($100\%$); nutritional disorders ($100\%$); chorea-athetose ($95\%$); and hypersalivation ($95\%$). However, today, when the world is polluted by mercury in various places and at various levels, the data we need is not represented by those severe cases, but rather by the chronic milder type. Even in Minamata, the issue of Minamata disease has not been resolved. And likewise, on a global scale the problem of Minamata disease is not yet over.

• Korean Journal of Optics and Photonics
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• v.12 no.3
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• pp.235-239
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• 2001

In this paper, we propose an optical configuration of a reflective AFLC display mode using a half-wave AFLC cell in which inplane tilt angle is $22.5^{\circ}C$. To check the validity of our design, we fabricate a reflective half-wave AFLC cell of which the in-plane tilt angle is $24.9^{\circ}C$, and measure viewing angle and visible spectra characteristics. In the results, the half-wave AFLC cell in the reflective configuration exhibits wide viewing-angle as well as high brightness and contrast. trast.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.4
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• pp.457-468
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• 2007

Statements of problem: The fracture of acrylic resin dentures remains an unsolved problem. Therefore, many investigations have been performed and various approaches to strengthening acrylic resin, for example, the reinforcement of heat-cured acrylic resin using glass fibers, have been suggested over the years. Silane is important for bonding between glass fiber and resin. Purpose: The aim of the present study was to investigate the effect of various silane on the strength of PMMA resin and roughness of resin-glass fiber complex after abrasion test. Material and methods: 3mm glass fiber (Chopped strand, Hankuk fiber Co., Milyang, Korea) was treated with 3 kinds of silane (MPS, EPS, APS) (Sila-ace, Chisso chemical, Tokyo, Japan) and mixed with PMMA resin(Vertex RS, Vertex Dental B.V., Zeist, Netherlands). Transverse strength and Young's modulus was measured using Instron (Instron model 4466, Instron, Massachusetts, USA). After abrasion test (The 858 Mini Bionix II Test System, MTS System Co., Minnesota, USA) surface roughness was evaluated using tester (Form Talysurf plus, Taylor Hopson Ltd., Leicester England). Examination of scanning electron microscope was also performed. Results: Within this study, the following conclusions were drawn. 1. Surface treatment of glass fiber with MPS and APS increased transverse strength of PMMA resin complex, but surface treatment with EPS decreased transverse strength of PMMA resin complex (p<0.05). 2. Silane treated glass fiber increased Young's modulus of PMMA resin complex compared to desized glass fiber (p<0.05). 3. Roughness increased after abrasion test in case of PMMA resin reinforced with desized glass fiber (p<0.05). 4. Roughness change was not observed after abrasion test in case of PMMA resin reinforced with silane treated glass fiber (p>0.05).