• 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.

• Archives of Plastic Surgery
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• 제39권2호
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• pp.138-142
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• 2012

Background : Electrical burns are one of the most devastating types of injuries, and can be characterized by the conduction of electric current through the deeper soft tissue such as vessels, nerves, muscles, and bones. For that reason, the extent of an electric burn is very frequently underestimated on initial impression. Methods : From July 1999 to June 2006, we performed 15 cases of toe tissue transfer for the reconstruction of finger defects caused by electrical burns. We performed preoperative range of motion exercise, early excision, and coverage of the digital defect with toe tissue transfer. Results : We obtained satisfactory results in both functional and aesthetic aspects in all 15 cases without specific complications. Static two-point discrimination results in the transferred toe cases ranged from 8 to 11 mm, with an average of 9.5 mm. The mean range of motion of the transferred toe was $20^{\circ}$ to $36^{\circ}$ in the distal interphalangeal joint, $16^{\circ}$ to $45^{\circ}$ in the proximal interphalangeal joint, and $15^{\circ}$ to $35^{\circ}$ in the metacarpophalangeal joint. All of the patients were relatively satisfied with the function and appearance of their new digits. Conclusions : The strategic management of electrical injury to the hands can be both challenging and complex. Because the optimal surgical method is free tissue transfer, maintenance of vascular integrity among various physiological changes works as a determining factor for the postoperative outcome following the reconstruction.

• 한국의류산업학회지
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• 제16권1호
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• pp.145-152
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• 2014

The usage of textile-based sensors has increased due to their many advantages (compared to IT sensors) when applied to body assessment and comfort. Textile-based sensors have different detecting factors such as pressure, voltage, current and capacitance to investigate the characteristics. In this study, textile-based sensor fabrics with sheath-core type conductive yarns were produced and the relationship between capacitance changes and applied load was investigated. The physical and electric properties of textile-based sensor fabrics were also investigated under various laminating conditions. A textile based pressure sensor that uses a sheath-core conductive yarn to ensure the stability of the pressure sensor in the textile-based sensor (the physical structure of the reaction characteristic of the capacitance) is important for the stability of the initial value of the initial capacitance value outside the characteristic of the textile structural environment. In addition, a textile based sensor is displaced relative to the initial value of the capacitance change according to pressure changes in the capacitance value of the sensor due to the fineness of the high risk of noise generation. Changing the physical structure of the fabric through the sensor characteristic of the pressure sensor via the noise generating element of laminating (temperature, humidity, and static electricity) to cut off the voltage output element to improve the data reliability could be secured.

• Journal of Electrical Engineering and Technology
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• 제3권3호
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• pp.391-400
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• 2008

Multi-pulse topology of converters using elementary six-pulse GTO - VSC (gate turn off based voltage source converter) operated under fundamental frequency switching (FFS) control is widely adopted in high power rating static synchronous compensators (STATCOM). Practically, a 48-pulse ($6{\times}8$ pulse) configuration is used with the phase angle control algorithm employing proportional and integral (PI) control methodology. These kinds of controllers, for example the ${\pm}80MVAR$ compensator at Inuyama switching station, KEPCO, Japan, employs two stages of magnetics viz. intermediate transformers (as many as VSCs) and a main coupling transformer to minimize harmonics distortion in the line and to achieve a desired operational efficiency. The magnetic circuit needs altogether nine transformers of which eight are phase shifting transformers (PST) used in the intermediate stage, each rating equal to or more than one eighth of the compensator rating, and the other one is the main coupling transformer having a power rating equal to that of the compensator. In this paper, a two-level 48-pulse ${\pm}100MVAR$ STATCOM is proposed where eight, six-pulse GTO-VSC are employed and magnetics is simplified to single-stage using four transformers of which three are PSTs and the other is a normal transformer. Thus, it reduces the magnetics to half of the value needed in the commercially available compensator. By adopting the simple PI-controllers, the model is simulated in a MATLAB environment by SimPowerSystems toolbox for voltage regulation in the transmission system. The simulation results show that the THD levels in line voltage and current are well below the limiting values specified in the IEEE Std 519-1992 for harmonic control in electrical power systems. The controller performance is observed reasonably well during capacitive and inductive modes of operation.

• 조명전기설비학회논문지
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• 제21권3호
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• pp.88-95
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• 2007

국내 승강기 사고는 사망 등 인명에 관련된 피해 사고가 꾸준히 발생을 하고 있다. 본 연구는 이들의 직접적인 원인 규명은 아니지만, 승강기 설비의 고장 및 오동작 등에 연관 될 수 있는 전원품질에 관하여 승강기 분전반에서의 현장 측정 및 분석하였고, 또한 고장 및 보수에 관한 현장 오동작에 관하여 설문조사 하였다. 결론적으로 전원품질(Sag, Interruption, Harmonic, 전자기 방사 파형, 정전기 등)이 승강기 동작에 영향을 줄 수 있다는 것을 승강기 설비의 세 모델 시험을 통하여 결과를 얻었고 그 오동작에 대한 대책을 제시하였다. 본 연구 결과는 국내 승강기 산업의 기술 발전과 승강기를 이용하는 사용자의 최소한 안전을 위해 승강기 검사 관련 규정 및 KS 관련 규정 개정을 제시하는데 자료로 사용 될 것이다.

• 사물인터넷융복합논문지
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• 제5권2호
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• pp.73-79
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• 2019

현재 질식 가스 및 폭발위험이 있는 물질에 대하여 실시간으로 경고를 제공하는 서비스 및 시스템에 관한 연구가 진행되고 있지만, 현재 스마트 형 밴드 형태의 서비스는 미비한 실정이다. 본 연구에서는 작업장 내의 정전기로 인한 폭발위험요소의 실시간 확인 및 사고 발생 요인의 즉각적인 제거를 지원하고 작업자 상태 및 작업장의 위험요소(산소, 유해 화학 물질 농도)등의 실시간 모니터링 및 위험 발생시 즉시 경고 및 데이터 분석을 통한 사전 사고 예방시스템 구축방법을 제안한다. 이로써, 산업현장에서 발생할 수 있는 각종 재해를 IoT 기반의 지능형 센서노드, 무선 네트워크기술 그리고 데이터 가공 미들웨어 및 통합 관제시스템을 이용해 모니터링하고 실시간 산업현장에서의 위험정보를 전달함과 동시에 사고를 예방해 작업자의 안전한 작업환경 지원으로 사후 수습 비용 대비 획기적 비용절감을 할 수 있다.

• 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.

• 한국전산구조공학회논문집
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• 제20권4호
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• pp.463-468
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• 2007

최근 일본에서 발생한 지진으로 이동통신용 전자장비들이 많이 파손되었으나. 국내에서 제작되어 일본에 설치된 모제품은 강진에서도 대부분 구조적 손상이 없었다. 본 논문에서는 이동통신 네트워크 장비의 정/동적 특성을 평가하기 위하여 제품의 유한요소 모델을 생성하여 정적 및 동적 구조해석을 수행하였다. 또한 Zone 3 GR-63-CORE 동적 실험을 수행하여 제품의 안정성을 검증하였고, 유한요소 구조해석 결과와 비교하여 실험과 해석 결과가 유사함이 입증되었다. 구조해석 결과인 동적 응답특성은 실험보다 다소 크게 나왔으며, 부재의 특성파악을 위해 구조물의 치수를 설계변수로 하여 진동특성에 대한 민감도 해석으로 고유진동수에 민감한 부재를 판별하였고, 치수변경으로 경량화 설계치를 산출하였다. 경량화된 디자인의 동적 응답변위가 원래 디자인보다 작게 나와 최적화 결과가 유용할 것으로 보인다.

• 한국생활과학회지
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• 제7권2호
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• pp.81-91
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• 1998

The subjects in this research were 368 girls in high school for survey, and wearing sensation and physiological responses were investigated through wearing trials on human body in climatic chamber based on these results from the survey. The results are as follows : 1. They enjoyed wearing t-shirts, jackets, vests, and blouses in order for the upper clothes, and they preferred t-shirts to blouses. For the lower clothes, they enjoyed slacks much more than skirts. The weight of clothes was significantly heavier in the group where they wore the uniforms(U-group) than in the group where they wore the free styles(F-group). When they chose the school wear, activity was the most important of all, and the maintenance was the least. 2. As the classes were a little cool and dry, most of them dissatisfied the environment. The degree of the satisfaction of the class environment and properties to it were higher in the U-group than in F-group. 3. In the textiles, colors, styles, activity, static electricity, seasonal property, and easiness of putting on and taking off the clothes, F-group was more satisfied than U-group. U-group was more satisfied than F-group in the soil of the clothes. 4. The thermal comfort, thickness, and tightness of the clothes were not significantly different between the groups. The clothes of U-group was heavier than those of F-group, and the tactile sensation in U-group was worse than F-group. In U-group the students felt the skirts very inconvenient when they acted. 5. The weight of the clothes influenced the wearing sensation, therefore the heavier the clothes were the less satisfied they felt. 6. The inside temperature of clothes was significantly higher in U-group than in F-group. The skin temperatures of abdomen and arm were significantly higher in U-group than in F-group, while the skin temperatures of thighs and legs were significantly lower in U-group than in F-group. U-group felt heavier than F-group in wearing the clothes. Therefore the improvement of the clothes weight is needed.

• 한국가스학회지
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• 제18권4호
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• pp.35-43
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• 2014

무기질 바닥마감재로 기존 위험물 저장시설의 유기질계 바닥재의 문제점을 극복할 수 있다. 하지만 기존 시공된 바닥재를 제거하는데 있어서 제거기와 바닥재의 물리적 충돌에 의해 불꽃이 발생될 수 있다. 이러한 위험물 저장시설에서의 폭발에 의한 화재가 발생할 수 있는 위험요소를 억제하도록 기존 바닥재를 제거하지 않고 시공할 수 있다. 또한, 상도제는 대전방지제가 함유되어 있어 위험물 저장시설에 있어서 바닥마감재 시공 후 발생될 수 있는 정전기에 의한 2차적 피해를 억제 할 수 있어 효과적이다. 따라서 본 연구에서 개발된 무기질 바닥마감재는 점검자의 안전 관리적 측면과 경제적 측면에 효과가 있을 것으로 기대된다.