• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 추계학술대회 논문집
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• pp.743-749
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• 2012

Grunt (Stick-slip) noise happens between rear lining and drum on braking condition while vehicle is returning to steady position after nose-dive. The study presents a new testing and analysis methods for improving brake grunt noise on vehicle. Grunt noise is called a kind of stick slip noise with below 1kHz frequency that is caused by the surfaces alternating between sticking to each other and sliding over each other with a corresponding change in friction force. This noise is typically come from that the static friction coefficient of surfaces is much higher than the kinetic friction coefficient. For the identification of the excitation mechanism and improvement of grunt noise, it is necessary to study variable parameters of rear drum brake systems on vehicle and to implement CAE analysis with stick slip model of drum brake. The aim of this study has been to find solution parameters throughout test result on vehicle and dynamo test. As a result of this study, it is generated from stick slip between rear lining and rear drum and it can be solved to reduce contact angle of lining with asymmetric and is effected not only brake drum strength but also rear brake size and brake factor.

• 한국재료학회지
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• 제16권2호
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• pp.106-110
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• 2006

We have investigated the effect of the experimental variables such as temperature and pressure on conformality of Co films deposited over high aspect ratio trenches using $Co_2(CO)_8$ as a precursor. The results show that the conformality of Co films is a strong function of temperature and process pressure. Lowering the pressure and temperature significantly improves the conformality. As the pressure decreases from 0.6 Torr to 0.2 Torr at $50^{\circ}C$, the bottom coverage of Co films over $0.2{\mu}m$ width trenches with an aspect ratio of 13 to 1 significantly increases to 85%. However, further increasing the temperature from 50 to $60^{\circ}C$ at the pressure of 0.2 Torr degrades the bottom coverage to 14%. In contrast, the extremely low pressure of 0.03 Torr allows the excellent conformal deposition of Co films up to $70^{\circ}C$. This can be attributed to the suppression of homogeneous reaction in the gas phase, which can create the intermediate products with high sticking coefficient. In addition, the Co films deposited at $50^{\circ}C$ show the low resistivity with negligible contamination. As a result, the newly developed Co process using MOCVD can be implemented into the next generation devices with complex shapes.

• 공업화학
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• 제10권2호
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• pp.225-230
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• 1999

Li(DPM)을 원료로 hot wall 수평 관형 반응기를 이용하여 질소-산소 및 아르곤-산소의 분위기에서 $Li_2O$ 고체박막을 LPMOCVD법으로 합성하였다. XRD와 ESCA 분석으로부터 질소-산소 분위기에서는 $Li_2CO_3$막이, 아르곤-산소의 분위기에서는 $Li_2O$막이 성장하였음을 알아냈다. 성막된 산화리튬과 리튬카보네이트는 기판의 실리콘 성분과 반응하여 실리케이트를 형성하였다. 마이크로 trench법과 Monte Carlo 시뮬레이션에 의해 기상반응 속도상수 및 표면반응 속도상수가 얻어졌으며 이를 이용한 성막속도 계산치와 실험치를 비교한 결과 실험조건범위 내에서 잘 일치하였다.

• 한국염색가공학회지
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• 제29권3호
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• pp.122-130
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• 2017

In the direct digital textile printing process, the pre-treatment process is an essential condition for products by forming a clear pattern by sticking and penetration of DTP dye without spreading on the fabric. Recently, pre-treatment agent is changing from high viscosity to low viscosity in order to reduce defects of fabric during pre-treatment process. In this study, pre-treatment agent of acrylic polymer with low viscosity(less than 50cps) was prepared according to the solid content of the polymer, pre-treated on the cotton fabric, and direct DTP printing was performed to compare the color and sharpness. As a result, it showed high color at a viscosity of 50cps or less. When the solid content of the polyacrylic acid having a high molecular weight(A1) was 2.5wt%, when the solid content of the polyacrylic acid having a low molecular weight(A2) was 1 - 1.5wt%, the color was the best. And when the solid content of A1 and A2 was 1.5wt%, the degree of spreading was small and A1 was superior to A2 at the sharpness.

• 디지털융복합연구
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• 제13권7호
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• pp.373-380
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• 2015

본 연구는 테니스 한손과 양손 백핸드 스트로크 동작에서 하지관절 움직임의 차이를 확인하여 유형별 특성을 밝히는데 그 목적이 있으며 그 결과는 다음과 같다. 볼의 속도를 결정하는 중요한 요인인 라켓헤드의 합성 속도는 양손 백핸드 스트로크 동작이 한손보다 빠른 속도를 나타냈다. 양손 백핸드 스트로크는 하체의 움직임을 최소화시키고 몸통 회전을 통한 스트로크를 하는 반면 한손 백핸드 스트로크는 몸통을 이용한 스트로크를 하기 보다는 공을 쫓아가듯이 스트로크 하는 것으로 나타났다. 슬관절의 신전모멘트는 한손 백핸드 스트로크가 큰 것으로 나타났지만, 내번모멘트와 회내모멘트 그리고 굴곡모멘트는 양손 스트로크에서 크게 나타났다. 고관절의 경우 신전, 내번, 회내 모멘트가 양손 백핸드 스트로크가 한손 보다 모두 큰 것으로 나타났는데 특히 내번모멘트의 경우 큰 차이를 나타난 반면, 외번모멘트는 한손 백핸드 스트로크가 큰 것으로 나타났다.

• Korean Journal of Acupuncture
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• 제22권4호
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• pp.91-107
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• 2005

To study the effects of EF(Eriobotryae Folium) herbal acupuncture on asthma, we injected EF-HAS into Jok-samni(ST36) of C57BL/6 mice Objective : The aim of this study was to investigate the effect of EF-HA(herbal acupuncture) at ST36 on ovalbumin-induced asthma in mice Methods : C57BL/6 mice were sensitized and challenged with OVA(ovalbumin) for 12 weeks(once a week). Experimental groups were treated with concentrations(1%) of EF-HA at Jok-samni(ST36) for the later 8 weeks(3times/week). Result : 1. The weight and total cells of lung of the mice group treated with EF-HA decreased significantly compared with that of Control group. 2. Total Leukocytes and Eosinophils in BALF of the mice group treated with EF-HA decreased significantly compared with those of Control group. 3. The sticking of collagen on histological analysis of lung sections, the mice group treated with EF-HA decreased significantly compared with those of Control group. 4. The concentration of IgE, IL-4, IL-5 in BALF of the mice group treated with EF-HA decreased significantly compared with those of Control group. 5. The concentration of IL-4, IL-5, IL-13 in Serum of the mice group treated with EF-HA decreased significantly compared with those of Control group. 6. The number of $Gr-1^+/CD11b^+,\;CD3^-/CCR3^+,\;CD4^+,\;CD8^+,\;CD3e^+/CD69^+$ cells in the lungs of the mice group treated with EF-HA decreased significantly compared with those of Control group. 7. The cytokine's manifestation of mRNA of the mice group treated with EF-HA with RT-PCR decreased significantly compared with that of Control group. Conclusion : We conclude that EF-HA is effective on OVA-induced asthma of C57BL/6 mouse.

• 한국콘텐츠학회논문지
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• 제12권6호
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• pp.448-456
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• 2012

본 연구의 목적은 무엇이 여가다운 여가인가를 되짚어 보고, 속도경쟁 사회에서 우리에게 진정으로 필요한 여가는 무엇인가에 대한 성찰의 기회를 제공하는 것이다. 이를 위해 주요 여가개념을 분석하여 이 개념 안에 함축된 우리 사회의 가치판단을 읽어내고, 여가 본연의 가치를 회복하기 위해 필요한 논의를 전개하였다. 결론은 다음과 같다: 첫째, 자기계발과 사회통합 등 사회 순기능적 효과를 가져 오는 진지한 여가의 상대적 우월성을 강조하다보니 일상적 여가가 지닌 본연의 가치는 하향 평가되는 오류를 범하였다. 일상적 여가는 그 자체를 수행함으로써 삶의 균형을 이루려는 인간 본연의 욕구를 충족시켜줄 뿐 아니라 신체적, 심리적으로도 긍정적인 효과를 동반한다는 점을 간과하지 말아야 한다. 둘째, 진지한 일상적 여가의 이분법적 구조의 오류를 극복하기 위해 여가행위의 재연방식으로 정의한 빠른 느린 여가 개념에 대한 이론적 검토가 좀 더 세밀히 이루어져야 할 것이다. 셋째, 우리가 구태의연하고 생산적이지 못하다고 배척해온 삶의 방식도 그 자체를 구현함으로써 충분히 의미가 있다는 의식의 전환이 필요하다.

• 한국가스학회지
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• 제21권2호
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• pp.26-31
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• 2017

이 논문은 디젤 자동차의 터보차저 시스템에 관련된 고장사례를 연구하기 위한 것이목적이다. 첫 번째 사례는 터보차저를 분해하여 확인한 결과 터보 휠의 파손으로 터빈이 손상되어 작동되지 않음으로 배기관 구멍이 막혀 가속이 되지 않는 것을 확인하였다. 터보차저 장착차량의 경우 높은 회전수에서는 엔진을 바로 정지시키게 되면 고온에 의한 터보의 고착현상이 발생될 수 있으므로 공회전 상태를 충분히 유지한 다음 시동을 끄도록 한다. 두 번째 사례는 터보차저를 작동시키는 VGT 액튜에이터의 로드가 고착되어 가속불량 현상이 발생된 것으로 확인되었다. 세 번째 사례는 알터네이터(Alternator) 저항과 인터쿨로 팬 릴레이 커넥터 오조립으로 인해 주행 중 출력부족 현상이 발생한 것을 확인하였다. 따라서, 터보차저 시스템의 철저한 관리를 통해 고장이 발생하지 않도록 하여야 한다.

• 한국전기전자재료학회논문지
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• 제18권5호
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• pp.389-395
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• 2005

The etching technology of the high aspect ratio contact(HARC) is necessary at the critical contact processes of semiconductor devices. Etching the $SiO_{2}$ contact hole with the sub-micron design rule in manufacturing VLSI devices, the unexpected phenomenon of 'profile tilting' or 'bottom distortion' is often observed. This makes a short circuit between neighboring contact holes, which causes to drop seriously the device yield. As the aspect ratio of contact holes increases, the high C/F ratio gases, $C_{4}F_{6}$, $C_{4}F_{8}$ and $C_{5}F_{8}$, become widely used in order to minimize the mask layer loss during the etching process. These gases provide abundant fluorocarbon polymer as well as high selectivity to the mask layer, and the polymer with high sticking yield accumulates at the top-wall of the contact hole. During the etch process, many electrons are accumulated around the asymmetric hole mouth to distort the electric field, and this distorts the ion trajectory arriving at the hole bottom. These ions with the distorted trajectory induce the deformation of the hole bottom, which is called 'profile tilting' or 'bottom distortion'. To prevent this phenomenon, three methods are suggested here. 1) Using lower C/F ratio gases, $CF_{4}$ or $C_{3}F_{8}$, the amount of the Polymer at the hole mouth is reduced to minimize the asymmetry of the hole top. 2) The number of the neighboring holes with equal distance is maximized to get the more symmetry of the oxygen distribution around the hole. 3) The dual frequency plasma source is used to release the excessive charge build-up at the hole mouth. From the suggested methods, we have obtained the nearly circular hole bottom, which Implies that the ion trajectory Incident on the hole bottom is symmetry.

• 한방안이비인후피부과학회지
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• 제29권2호
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• pp.142-148
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• 2016

Objectives : The objective of this study was to report the efficacy of the Crucial Incision Acupuncture Therapy(CIAT) for removing melanocytic nevi. Methods : CIAT is penetration acupuncture to remove a lesion by sticking needles like cross-shape. We used the CIAT for treating one patient with melanocytic nevi, and then we investigated efficacy and side effect for about 5 months. Results : In 16 melanocytic nevuses treated with CIAT, one of the nevuses recurred after about 3 months. And hyperpigmentation lasted for about 2-5 months was caused after the CIAT. Conclusions : In Korean medicine, the CIAT might be used for treating melanocytic nevi. But additional studies might be needed for improvement of treatment effect.