• 대한기계학회논문집
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• 제17권9호
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• pp.2315-2328
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• 1993

The turbulence effect of particle deposition on a horizontal free-standing wafer in a vertical flow has been studied numerically by using the low-Reynolds-number k-.epsilon. turbulence model. For both the upper and lower surfaces of the wafer, predictions are made of the averaged particle deposition velocity and its radial distribution. Thus, it is now possible to obtain local information about the particle deposition on a free-standing wafer. The present result indicates that the particle deposition velocity on the lower surface of wafer is comparable to that on the upper one in the diffusion controlled deposition region in which the particle sizes are smaller than $0.1{\mu}m$. And it is found in this region that, compared to the laminar flow case, the averaged deposition velocity under the turbulent flow is about two times higher, and also that the local deposition velocity at the center of wafer is high equivalent to that the wafer edge.

• 대한물리의학회지
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• 제7권1호
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• pp.59-67
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• 2012

Purpose : This study was somatosensory less in patients with idiopathic scoliosis somatosensory input to the lumbar stabilization exercises carried out to determine the most effective treatment method to be stable and unstable in terms of supporting the lumbar stabilization exercises the patient's torso length and postural sway by comparing the distance from a standing position and looked for differences in effect on the balance. Methods : The subjects of the study were 18 patients who showed the symptom of scoliosis. The study classified the patients into two experimental groups, one using an unstable surface and one a fixed surface, and the patients were required to do a lumbar stabilization exercise a total of 12 times for 60 minutes per session, three times a week for four weeks. The study carried out a paired comparison t-test so as to compare differences between measurement values in each experimental group before and after the exercise. Results : Superior iliac spine on the left, there was a significant reduction in the group doing the lumbar stabilization exercise on an unstable surface (p<0.05). Regarding change in sway distance to the left and right directions in the group doing the lumbar stabilization exercise on the unstable surface, there was a significant decrease in both the condition of closed eyes or open eyes (p<0.05). As for change in sway distance in forward-and-backward direction, there was a significant reduction in the condition of either closed eyes or open eyes (p<0.05). Conclusion : The lumbar stabilization exercise on an unstable surface improved the trunk posture of patients with scoliosis symmetrically, and the static balance ability in a standing posture was discovered to be improved. In the future, the lumbar stabilization exercise on an unstable surface may be used as a posture correction and balance increase exercise for patients with scoliosis.

• 대한물리의학회지
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• 제12권1호
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• pp.75-81
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• 2017

PURPOSE: The purpose of this study was to compare the activity of the abductor hallucis (AbdH) muscle during short foot exercise (SFE) using foot orthosis (SFE-FO) and the windlass effect (SFO-WE) while sitting and in a one-leg standing position. METHODS: We recruited fourteen subjects with normal feet for this study. Surface electromyography (EMG) was used to measure the muscle activity of the AbdH muscle during SFE, SFE-FO, and SFE-WE while sitting and in a one-leg standing position. Three trials consisting of a 5 s hold for each of the three exercises were performed to measure the EMG activity of the AbdH muscle. Exercise type and position were randomly assigned. Two-way repeated-measures ANOVA was used to analyze the effects of exercise type (SFE vs. SFE-FO vs. SFE-WE) and position (sitting vs. one-leg standing position) on AbdH muscle activity. A statistical significance was set at ${\alpha}=.05$. RESULTS: The EMG activity of AbdH muscle in the SFE-WE exercise was significantly greater than that during SFE and SFE-FO in both exercise positions (p<.001). In addition, the EMG activity of the AbdH muscle in the one-leg standing position was significantly higher than that while sitting (p<.001) during all three exercises. CONCLUSION: These results suggest that SFE-WE is a more effective strengthening exercise than SFE or SFE-FO for activating the AbdH muscle.

• The Journal of Korean Physical Therapy
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• 제24권3호
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• pp.216-222
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• 2012

Purpose: Weight-bearing exercise is a type of physical exercise that is widely performed for rehabilitation after acquiring nervous-system diseases or sports-related injuries. It is one of the most commonly prescribed rehabilitation programs for strengthing of the lower extremities. Weight-bearing exercise is important for the conduct of such activity of daily living (ADLs) as walking, and up and down the stairs. The purpose of this study was to investigate the muscle activities during one-leg standing and one-leg squatting, the two most representative weight-bearing exercises. Methods: A total of 43 elderly (60~70 years old) males who could perform weight-bearing exercises were included in the study. During the one-leg standing and one-leg squatting, the electromyographic (EMG) signals were quantified as maximum voluntary isometric contraction (%MVIC) using surface EMG, and then the muscle activities of the lower extremities during the two exercises were compared. For statistical analysis, an independent sample t-test and one-way ANOVA were performed. Results: The results of the study are as follows: (1) in the one-leg standing, the activity of the gluteus medius was the greatest among the vastus medialis, vastus lateralis, bicep femoris, (2) in the one-leg squatting, the activity of the vastus medialis was the greatest; and (3) the activity was greater in the one-leg squatting than in the single-leg standing exercise. Conclusion: The one-leg standing and squatting exercises are suitable for strengthening the muscles for the prevention of and recovery from lower-extremity injury, and for functional ADL in elderly people. In addition, dynamic exercise was shown to be more effective than static exercise for strengthening the muscles.

• 박물관보존과학
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• 제19권
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• pp.69-82
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• 2018

국립청주박물관 소장 충북 영동 영국사 출토 금동여래입상과 동제여래입상의 과학적 조사와 보존처리를 하였다. 성분분석 결과, 금동여래입상은 구리, 주석, 납의 삼원계, 동제여래입상은 구리, 주석의 이원계 합금으로 확인되었다. 동제여래입상 성분분석 결과 금이 확인되어 금동여래입상으로 명칭이 수정되어야 할 것이다. 금동여래입상은 국내에서 생산된 납을 원료로 하여 제작되었을 것으로 유추할 수 있었고, 표면에 존재하는 개금을 위한 접착제로 보이는 물질은 분석을 통해 옻으로 추정되었다. 보존처리는 상태를 확인하여 물리적, 화학적 방법으로 최소한의 이물질을 제거하고, 안정화처리 및 보호 코팅의 과정을 거쳤다.

• 자원환경지질
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• 제39권6호
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• pp.629-641
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• 2006

논산 관촉사 석조미륵보살입상은 흑운모가 많은 중립 내지 조립질 화강섬록암으로서 암회색을 띠며, 미약한 편마상 구조 및 페그마타이트 세맥이 발달한다. 이 석불입상과 기반암의 전암 대자율 측정 및 지구화학적 분석 결과, 두 암석은 동일 마그마로부터 형성되어 거의 유사한 분화과정을 경험한 것으로 보인다. 이 암석의 CIA는 기반암이 51.43, 석불입상이 50.86이며, WPI는 각각 4.52와 8.95로서 이들은 모두 풍화잠재력이 큰 것으로 나타났다. 이 석불입상은 열화 및 박리에 의한 물리적 풍화가 진행된 상태이고, 이차적인 오염물질과 침전물질이 산재해있다. 기반암도 불연속면의 발달에 따른 지반붕괴의 위험성을 내포하고 있다. 이 석불입상의 표면은 황갈색으로 변색되어 있고 암회색 및 암흑색 침전물이 형성되어 있다. 또한 고착지의류의 피도가 심하고 균류, 조류 혹은 선태류 등도 발견된다. 따라서 이석불입상의 복합적 손상에 영향을 줄 수 있는 요인들을 제어하기 위한 주변 환경에 대한 정리가 시급하며 지의류에 의한 오염, 박리 및 균열로부터 석불입상을 보호하기 위한 체계적인 보존과학적 관리가 요구된다.

• 한국표면공학회지
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• 제34권4호
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• pp.281-288
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• 2001

Phosphating treatments have been performed to improve paint adhesion and corrosion resistance of zinc and zinc alloy coated steels for a long time. In this work, the effects of the addition of chelate compound were studied to improve the stability of surface conditioning solution and properties of zinc phosphate films. The coalescence of colloidal Ti-compound and extraneous charged particles (alkaliearth metal cation such as $Mg^{2+}$ , $Ca^{2+}$ ) were suppressed by using a surface conditioning solution with chelate compound. Therefore, after surface conditioning solution containing chelate compound was left standing for one week at room temperature, the formation of a white sediment was decreased comparing to surface conditioning solution without chelate compound. The crystal size of phosphate film was fine and the whiteness value of phosphated zinc coated steel sheets was also high without the decrease of corrosion resistance and anti-patina. It was very effective to use chelate compound improving the stability of surface conditioning solution.

• 박물관보존과학
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• 제23권
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• pp.1-16
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• 2020

이 논문에서는 부여 규암리 출토 '금동관음보살입상(국보 제293호, M335번)' 1점을 현미경으로 확대 관찰하여 제작기법을 확인하였고, XRF 성분분석과 Hard X-선 조사로 구성 성분과 불상 표면 처리 방법, 주조법을 확인하였다. 이 불상은 연화대좌 위에 직립하는 보살상이다. 불상 양 측면으로 흘러내린 천의와 대좌에 표현된 연화문의 모양을 볼 때 7세기 이후에 만들어진 불상의 특징을 하고 있다. 대좌 안쪽에서 내형과 외형을 고정시키기 위한 틀잡이와 주물의 주입 흔적이 관찰되었다. 또한, 주조기법은 팔과 대좌 부분에 청동 주물시 형성된 기포가 확인되어 이를 종합해 볼 때 고대 중소형 금동불 제작에 많이 사용되는 밀납주조법으로 제작한 것으로 판단된다. 성분분석 결과, 불상 내부에서는 시기적으로 6~7세기에 많이 나타나는 구리(Cu)-주석(Sn)-납(Pb) 계열의 3원계 합금을 사용한 것으로 확인되며 이는 금속을 합금하여 주조를 쉽게 하고 불상에 표현된 문양 및 장식을 선명하게 표현하고자 하는 의도로 추정된다. 불상 표면에서는 수은(Hg)이 검출되어 금(Au)을 수은(Hg)에 용해시켜 도금하는 방식인 아말감도금기법을 사용했던 것으로 추정되며 이러한 도금방법은 고대 한반도에서 제작된 소형 금동불에서 주로 확인되는 불상의 도금 방식이다.

• The Journal of Korean Physical Therapy
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• 제15권3호
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• pp.1-15
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• 2003

The purpose of this study was to evaluate the change of lower extremity alignment according to plantar surface compliance in standing status. The thirty normal adults (15 men and 15 women) aged between 20 and 29 were assigned to 3 groups: control group, experimental groups (AHPS group, ASPH group). The lower extremity alignment was examined before and after adaptation with corresponding foam types. The results of this study were as follows : 1. As the result of comparing lower extremity alignment before and after test of the control group which any change did not exist in plantar surface compliance, there were not significant differences in the angle A, B, C, D, E of right and left(p>0.05). 2. As the result of comparing lower extremity alignment before and after test of the AHPS group which forefoot part of plantar surface is hard and rear foot part is soft, there were not significant differences in the angle A of right and left(p>0.05). But, there were significantly decreased in the angle B, C, D, E of right and left(p<0.05). 3. As the result of comparing lower extremity alignment before and after test of the ASPH group which forefoot part of plantar surface is soft and rear foot part is hard, there were not significant differences in the angle A of right and left(p>0.05). But, there were significantly increased in the angle B, C, D, E of right and left(p<0.05). 4. As the result of comparing lower extremity alignment of the control group, AHPS group and ASPH group, there were not significant differences in the angle A, B, C, D, E of right and left before test(p>0.05). But, there were significant differences in the angle C, D of right and left after test(p<0.05).

• Transactions on Electrical and Electronic Materials
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• 제10권2호
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• pp.40-43
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• 2009

The authors fabricated a nanopatterned surface on a GaN thin film deposited on a sapphire substrate and used that as an epitaxial wafer on which to grow an InGaN/GaN multi-quantum well structure with metal-organic chemical vapor deposition. The deposited GaN epitaxial surface has a two-dimensional photonic crystal structure with a hexagonal lattice of 230 nm. The grown structure on the nano-surface shows a Raman shift of the transverse optical phonon mode to $569.5\;cm^{-1}$, which implies a compressive stress of 0.5 GPa. However, the regrown thin film without the nano-surface shows a free standing mode of $567.6\;cm^{-1}$, implying no stress. The nanohole surface better preserves the strain energy for pseudo-morphic crystal growth than does a flat plane.