• Tribology and Lubricants
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• 제19권3호
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• pp.133-138
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• 2003

The characteristics for bimorph PZT cantilever of laboratory-fabricated have been evaluated experimentally. The deflections of cantilever with PZT are result from a capillary force between a water drop and a tip of cantilever. The output voltage due to deflect cantilever are depend on the tip shape and thickness of cantilever. We applied a bimorph PZT cantilever to oil thickness measurement. This reasonable concept is that the output voltage be caused by different defected characteristics between oil and surface. Experimental results demonstrated that the high measurement accuracy of the oil film thickness is obtained from the probe.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.248-251
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• 2004

This study was performed to propose the minimum thickness of RC slab that satisfies constructibility, fatigue safety, and serviceability requirements such as deflection control. Three different minimum thicknesses are calculated using concrete shear and rebar fatigue formulas, and deflection control, respectively, and checked by constructiblity. The maximum of these three minimum thicknesses is proposed as the minimum thickness of RC slab, which shows that the minimum thickness requirement of RC slab from Korean Bridge Design Code can be thinner than now.

• 대한의용생체공학회:의공학회지
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• 제34권2호
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• pp.80-90
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• 2013

Recently, functional insoles of wedge-type it is for the young to raise their height inserted between insole and heel cause foot pain and disease. Additionally, these have a problem with stability and excessively load-bearing during gait like high-heel shoes. In this study, we compared the changes in biomechanical characteristics of foot with different insole thickness then we will utilize for the development of the insole with the purpose of relieving the pain and disease. Subjects(male, n = 6) measured COP(center of pressure) and PCP(peak contact pressure) on the treadmill(140cm/s) using F-scan system and different insole thickness(0~50 mm) between sole and plantar surface during gait. Also, we computed changes of stresses at the foot using finite element model with various insole thickness during toe-off phase. COP moved anterior and medial direction and, PCP was increased at medial forefoot surface, $1^{st}$ and $2^{nd}$ metatarsophalangeal, ($9%{\uparrow}$) with thicker insoles and it was show sensitive increment as the insole thickness was increased from 40 mm to 50 mm. Change of the stress at the soft-tissue of plantar surface, $1^{st}$ metatarsal head represents rapid growth($36%{\uparrow}$). Also, lateral moments were increased over the 100% near the $1^{st}$ metatarsal as the insole thickness was increased from 0 mm to 30 mm. And it is show sensitive increment as the insole thickness changed 10 mm to 20 mm. As a result, it was expected that use of excessively thick insoles might cause unwanted foot pain at the forefoot region. Therefore, insole thickness under 30 mm was selected.

• 한국전문물리치료학회지
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• 제22권4호
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• pp.44-50
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• 2015

This study compared the effects of the initial head position (i.e., a HHP versus a relaxed head position) of subjects with and without a FHP on the thickness of the deep and superficial neck flexor muscles during CCF. The study recruited 6 subjects with a FHP and 10 subjects without a FHP. The subjects performed CCF in two different head positions: a HHP, with the head aligned so that the forehead and chin formed a horizontal line, and a relaxed head position (RHP), with the head aligned in a self-selected comfortable position. During the CCF exercise, the thickness of the longus colli (LCo) and the thickness of the sternocleidomastoid (SCM) were recorded using ultrasonography. The thickness of each muscle was measured by Image J software. The statistical analysis was performed with a two-way mixed-model analysis of variance. The thickness of the SCM differed significantly (p<.05) between the subjects with and without FHP. According to a post $h^{\circ}C$ independent t-test, the change in thickness of the SCM increased significantly during CCF in the subjects with FHP while adopting a HHP compared to that in the subjects without FHP. The change in thickness of the SCM was not significantly different between the two positions in subjects without FHP, and there was no significant change in thickness of the LCo muscle during the CCF exercise according to the initial position in both subjects with and without FHP. The results suggest that CCF should be performed in RHP to minimize contraction of the SCM in subjects with a FHP.

• 한국정보통신학회논문지
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• 제21권9호
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• pp.1627-1634
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• 2017

비정질 InGaZnO 박막 두께가 다른 무접합 트랜지스터를 제작하고 두께에 따른 양과 음의 게이트 스트레스 전압 및 빛을 비춘 상태에서 소자 불안정성을 분석하였다. 채널 박막 두께가 얇을수록 게이트 스트레스 및 빛이 인가된 상태에서 문턱전압 및 드레인 전류 변화가 큰 것을 알 수 있었다. 그 원인을 stretched-exponential 모델과 소자 시뮬레이션을 수행하여 설명하였다. 박막이 얇을수록 캐리어 트랩핑 시간이 짧기 때문에 전자나 홀이 빨리 활성화되는 것과 채널 박막의 뒷부분에서 채널의 수직 전계가 증가하여 전자나 홀을 많이 축적할 수 있는 것으로 설명하였다. IGZO 무접합 트랜지스터 제작에서 채널 박막의 두께를 결정할 때 채널 박막 두께가 얇을수록 소자 불안정성이 큰 것을 고려해야 됨을 알 수 있다.

• 한국산학기술학회논문지
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• 제15권2호
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• pp.646-652
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• 2014

본 논문의 목적은 AZ31 마그네슘합금의 균열성장거동의 경향을 묘사할 수 있는 실험적 피로균열전파모델을 시편두께 조건에서 평가하여 적합한 모델을 제시하는 것이다. 평가에 사용된 실험적 모델은 Paris-Erdogan 모델, Walker 모델, Forman 모델, 수정된 Forman 모델이며, 각 모델의 파라미터를 통계적으로 추정하기 위하여 최우추정법을 사용하였다. 두께조건이 피로균열전파거동 예측에 미치는 영향을 고려하면서 적합한 모델을 평가하기 위해 시편두께의 3가지 조건을 변화시키면서 피로균열전파실험을 수행하여 통계적 균열성장 데이터를 획득하였다. 시편두께 조건에 따라 마그네슘합금의 균열성장거동의 경향을 잘 묘사하는 모델은 Paris-Erdogan 모델과 Walker 모델이며, 모델의 파라미터 중 피로균열성장속도지수는 시편두께가 4.75mm와 6.60mm 조건에서 재료상수가 될 수 있음을 밝혀내었다. 그러나 시편두께가 두꺼운 경우에는 양상에 차이를 보이므로 모델 선정 시 신중한 판단이 요구된다.

• The Journal of Korean Physical Therapy
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• 제34권1호
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• pp.12-17
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• 2022

Purpose: Ankle dorsiflexion is an essential element of normal functions, including walking, activities of daily living and sport activities. The tibialis anterior (TA) muscle functioned as a dorsiflexor and as a dynamic stabilizer of the ankle joint during walking and jumping. This study aimed to compare TA muscle thickness using ultrasonography according to the four different toe and ankle postures for the selective TA strengthening exercise. Methods: This study were recruited 26 (males: 15, females: 11) aged 20-30 years, with no injury ankle and calf in the medical history, had normal dorsiflexion and inversion range of motion (ROM). The thickness of the TA muscle was measured by ultrasonography in the four different toe and ankle postures: 1. Ankle dorsiflexion with all toe extension and ankle inversion (ITEDF); 2. Ankle dorsiflexion with all toe flexion and ankle inversion (ITFDF); 3. Ankle dorsiflexion with all toe extension and neutral position (NTEDF); 4. Ankle dorsiflexion with all toe flexion and neutral position (NTFDF). One-way repeated analysis of variance (ANOVA) and Bonferroni correction were used to confirm the significant difference among conditions. The level of statistical significance was set at α=0.01. Results: TA muscle thickness with ITFDF was significantly greater than in any other ankle positions, including ITEDF, NTFDF, and NTEDF (p<0.01). Conclusion: Among the four toe and ankle postures, isometric contraction in ITFDF postures showed the greatest increase in thickness of TA rather than ITEDF, NTEDF, and NTFDF postures. Based on these results, ITFDF can be recommended in an efficient way to selectively strengthen TA muscle.

• 한국공작기계학회논문집
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• 제12권1호
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• pp.16-23
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• 2003

Keeping the layer thickness constant is very essential for improving the shape accuracy in the stereolithography process. The layer thickness is created by recoating process, and also affected by recoating parameters such as blade speed and thickness. The created layer in this process can determine the whole accuracy of the entire parts. The aim of this paper is to improve the accuracy of the layer thickness by adjusting the recoating process parameters. Several experiments with different recoating conditions are Performed to find the optimal recoating parameters that produce the most accurate layer thickness. The effective recoating method is suggested by measuring and analyzing the cured layer thickness.

• Transactions on Electrical and Electronic Materials
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• 제6권5호
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• pp.225-228
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• 2005

In this work, we studied the optimized copper thickness in Cu ECP (Electrochemical Plating). In order to select an optimized Cu ECP thickness, we examined Cu ECP bulge (bump, hump or over-plating amount), Cu CMP dishing and electrical properties of via hole and line trench over dual damascene patterned wafers split into different ECP Cu thickness. In the aspect of bump and dishing, the bulge increased according as target plating thickness decreased. Dishing of edge was larger than center of wafer. Also in case of electrical property, metal line resistance distribution became broad gradually according as Cu ECP thickness decreased. In conclusion, at least $20\%$ reduced Cu ECP thickness from current baseline; $0.8\;{\mu}m$ and $1.0\;{\mu}m$ are suitable to be adopted as newly optimized Cu ECP thickness for local and intermediate layer.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제28회 추계학술대회
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• pp.166-174
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• 1998

The distribution of oil film thickness in piston were measured by induced fluorescence method. A Xe lamp was used as light source. Coumarine-6 was mixed with oil as the fluorescent dye. Fluorescent signal which is proportional to the oil film thickness was acquired by CCD camera and transmitted to the personal computer as video signal. In order to solve the problem of measurement system, irregular distribution and unstability of light intensity, as well as to know the relationship between the oil film thickness and output signal, three different calibration techniques were used. Motoring and firing tests were performed in a single cylinder research engine with transparent liner. By analyzing the oil film thickness converted from the photographed image, it was observed that each of three piston rings scrapes the oil both upward and downward and oil film thickness is not uniform horizontally at a given piston land. The amount of oil in each land was considerably affected by the engine load. It is thought that the blow-by gas blows the oil down to the crankcase.