• 한국기계가공학회지
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• 제14권2호
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• pp.19-24
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• 2015

Gears are produced through a variety of methods. In general, a metal piece is formed into the general shape of a gear through rough cuts. The gear then moves on to a more precise machine that removes more material. Grinders work via abrasion, rubbing a rough surface against a work piece at such high speeds that it literally scrapes unwanted material away from the item. Since the grinder is spinning so fast, the material is removed very quickly. This allows a grinder to remove a very small amount without taking any unwanted material with it. This study investigates the effect of grinding process parameters like grinding spindle speed and table transfer speed on the gear grade and grinding efficiency.

• 한국기계가공학회지
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• 제10권2호
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• pp.79-83
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• 2011

Magnetic seal uses a magnetic fluid to seal a gap between a rotating shaft and housing. It is distinguished from other kinds of seals from the fact that solid contact does not occur in the seal. This implies that it is free from solid rubbing thus dustless and provides a clean circumstance. That is the reason why the magnetic seal is used exclusively for most of vacuum chambers in semiconductor process where dustless clean circumstance is critical. A magnetic seal has been developed of which design parameters are determined based on published data, and an air pressure test has been done to examine its sealing capability. Effects of some design parameters have been studied through FEM analysis. The results show some notable aspects of design parameters and provide suggestions for developing the seals. Regarding the sealing capacity of the magnetic seal the factor to match the theoretical value with the actual one was found to be 0.4~0.7, which means still there is some discrepancy between theory and actual.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.338-338
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• 2009

To date, rubbing has been widely used to align LC molecules uniformly. Although rubbing can be simple, it has fundamental problems such as the generation of defects by dust and static electricity, and difficulty in achieving a uniform LC alignment on a large substrate. Therefore, noncontact alignment has been investigated. Ion beam induced alignment method, which provides controllability, nonstop process, and high resolution display. We investigated the high pretilt angle effects on electro-optical properties of ion beam (IB)-irradiated liquid crystal cells. on a blended polymer surface. High pretilt angle of liquid crystals IB-irradiated on a blended polymer surface including such as 5% and 10% of homeotropic polymer contents can' be achieved. The threshold voltages of IB-irradiated twisted nematic (TN) cells on a blended polymer surface decrease with increasing the pretilt angle. Also, the rising time of IB-irradiated TN cells decreases with increasing the pretilt angle. However the decay time of IB-irradiated TN cells increases with increasing the pretilt angle. Consequently, the electro-optical properties of IB-irradiated TN cells depend strongly on the pretilt angle in a blended polymer surface.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 춘계학술대회 및 기술 세미나 논문집 디스플레이 광소자
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• pp.44-44
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• 2008

To date, rubbing has been widely used to align LC molecules uniformly. Although rubbing can be simple, it has fundamental problems such as the generation of defects by dust and static electricity, and difficulty in achieving a uniform LC alignment on a large substrate. Therefore, non contact alignment has been investigated. Ion beam induced alignment method, which provides controllability, nonstop process, and high resolution display. In this study, we investigated liquid crystal (LC) alignment with ion beam (IB) that non contact alignment technique on polyimide and electro-optical characteristics of twisted nematic (TN)-liquid crystal display (LCD) on the polyimide under various ion beam angles. In this experiment, Polyimide layer was coated on glass by spin-coating and Voltage-transmittance(VT) and response time characteristics of the TN cell were measured by a LCD evaluation system. The good characteristics of the nematic liquid crystal (NLC) alignment with the ion beam exposure polyimide surface was observed. The tilt angle of NLC on the PI surface with ion beam exposure can be measured under $1^{\circ}$ for all of irradiation angles. In addition, it can be achieved the good EO properties, and residual DC property of the ion beam aligned TN cell on polyimide surface.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.329-329
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• 2008

To date, rubbing has been widely used to align LC molecules uniformly. Although rubbing can be simple, it has fundamental problems such as the generation of defects by dust and static electricity, and difficulty in achieving a uniform LC alignment on a large substrate. Therefore, noncontact alignment has been investigated. Ion beam induced alignment method, which provides controllability, nonstop process, and high resolution display. In this study, we investigated liquid crystal (LC) alignment with ion beam (IB) that non contact alignment technique on polyimide and electro-optical characteristics of twisted nematic (TN)-liquid crystal display (LCD) on the poly imide under various ion beam angles. In this experiment, Polyimide layer was coated on glass by spin-coating and Voltage-transmittance(VT) and response time characteristics of the TN cell were measured by a LCD evaluation system. The good characteristics of the nematic liquid crystal (NLC) alignment with the ion beam exposure poly imide surface was observed. The tilt angle of NLC on the PI surface with ion beam exposure can be measured under $1^{\circ}4 for all of irradiation angles. In addition, it can be achieved the good ED properties, and residual DC property of the ion beam aligned TN cell on polyimide surface.

• 한국의류산업학회지
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• 제4권1호
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• pp.79-85
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• 2002

To develope natural dyeing materials from the unused plant materials, we had several dyeing experiments to investigate the optimum conditions of dyeing fabrics with the waste grape juice. Dyeing experiments were done under different dyeing conditions of dyeing time, dyeing temperature, pH and concentration of dyebath and mordants which were treated after dyeing. Experimental fabrics were silk, cotton, ramie and hemp. Color difference(${\Delta}E$) and Munsell's HV/C of the dyed fabrics and color fastness of silk dyed fabrics to dry cleaning, washing, rubbing, perspiration and light were measured. The color differences of dyed experimental fabrics were very slightly increased with dyeing time and the color of dyed silk was light purple and the cotton, ramie and hemp was light red purple. The color differences of dyed experimental fabrics were decreased and the color became lighter with dyeing temperature increased. The color differences of dyed experimental fabrics were decreased and the color changed from light purple to blue with the pH of dyebath increased. The color differences of dyed experimental fabrics were slightly increased with the concentration of dyebath increased. The color of dyed fabric changed with the mordant treatment and were different among the experimental fabrics. On the whole, blue tone increased with the Al and Fe mordant and green tone increased with the Cu mordant. The color fastness of dyed silk fabrics to light, washing (change) and perspiration (change) was bad and color fastness to dry cleaning and rubbing were good.

• Korean Journal of Acupuncture
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• 제22권4호
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• pp.175-185
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• 2005

Objective : The skill of locating acupoints accurately is an essential part of acupuncture treatment. Bone-scale has been used as a basic coordinates to locate acupoints and has been considered as an important factor of locating acupoints. This study was designed to stress the impotance of QieXunMenAn, which means pressing and rubbing softly the surface around the part pointed with proportional method, in locating acupoints. Methods and results : All expressions related with QieXunMenAn, among the descriptions of acupoint locations in ${\ulcorner}Zhenjiudacheng{\lrcorner}$, were investigated. The activity of QieXunMenAn has been regarded as an important method of locating acupoints since Neijing. QieXunMenAn means pressing and rubbing softly the surface around the part pointed with proportional method. It is a process of locating acupoint in detail by finger-sensation after locating the point with proportional method. Xianzhang, Dongmaiyingshou, and Wanwanzhong have been used to describe how to locate acupuncture-point through QieXunMenAn procedure. Xianzhong means a small depression or a pit on the surface of the body. Wanwanzhong describes that it feels very soft and tender. Descriptions related with QieXunMenAn procedures were found in around 87% of acupoint locations, thus stressing out its procedure. Conclusions : Bone-scale and QieXunMenAn do not mean different methods but the procedures that should be both performed every time when we locate most of the acupoints. Until recently, QieXunMenAn has been paid less attention that it should be. OieXunMenAn as well as bone-scale may be necessary to help locate acupoints accurately.

• 자원리싸이클링
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• 제13권1호
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• pp.39-46
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• 2004

마찰대전을 이용한 정전분리는 서로 상이한 물질간의 마찰을 통해 서로 다른 극성으로 하전시켜 이를 전기장내에 통과시켜 분리하는 기술이며, 플라스틱과 같은 부도체입자들의 정전분리에 많이 사용된다. 본 연구에서는 연속식 드럼형 마찰대전장치를 개발하고 이를 폐건축 및 폐가전 플라스틱의분리에 적용시켰다 분리대상 플라스틱은 폐건축 자재의 경우 PE/PVC 혼합시료를 대상으로 하였으며, 폐가전의 경우 ABS/PS/PP의 혼합시료를 대상으로 하였다. 건축자재 혼합플라스틱 및 가전제품 혼합플라스틱 모두 드럼형 마찰대전장치를 이용할 경우 실험한 조건에서 무게기준으로 95%이상의 순도조건에서 95%이상의 회수율을 보였다.

• 한국의류학회지
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• 제36권12호
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• pp.1310-1317
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• 2012

This study examines the possibilities to improve natural dyestuff's (Pinux$^{TM}$) dyeability and colorfastness for C/R (Cotton/Rayon (40/60)) and W/T (Wool/Tencel (10/90)) knitted fabrics in cationizing and smectiting for pre-treatment, simultaneous-treatment and post-treatment process sequences; as well as various other treatment methods. The sample dyeability showed the strongest K/S value in the order of smectite (S) < cationization + smectite (C+S) < cationization (C); however, the K/S value showed a low level in the simultaneoustreatment method of smectite. Colorfastness to washing improved in the order of C < C+S < S, and after the smectite post-treatment process, C/R improved from Grade 1 to Grade 4 and W/T improved from Grade 1-2 to Grade 4. Colorfastness to perspiration generally improved in the same order as the colorfastness to washing and after the smectite post-treatment process C/R, W/T sample's acidic and alkaline colorfastness to perspiration improved greatly. As for the colorfastness to rubbing, the addition of smectite in the simultaneous-treatment and post-treatment processes resulted in improved wet-colorfastness; however, smectite showed less effect on the colorfastness to light compared to other colorfastness ratings.

• 한국의류학회지
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• 제38권5호
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• pp.665-674
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• 2014

An analysis of the components of clay mineral before and after coloration (XRF) showed that the elements involved in coloration are Fe, Cr, and Ni. Fe accounts for 65% of coloring components on dyed fabric; in addition, Cr and Ni also affect coloring. The optimal coloration condition was to repeat the process of immersing the cotton fabric in $80^{\circ}C$ slurry of 8g of clay mineral to 1g cotton for 60 minutes, dry it for 24 hours and rinse three times. Especially, as the repetition of coloration increased, the $(K/S)_{440}$ value of sample A increased from 1.0 to 2.5, and sample B increased from 1.0 to 1.6. The effect of the repeated process on coloration was significant; consequently, the rinsing and drying process were important to decrease the coloration level. It also showed excellent results in regard to color fastness to washing, light, rubbing, perspiration, and antibiotic effect.