• Design & Manufacturing
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• 제15권3호
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• pp.13-18
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• 2021

In plate forming technology, cylindrical drawing process is widely used in industry due to technological development. In this study, we used stainless steel 3042B and stainless steel 304J1, which are the most commonly used materials in the production of cold and hot water tanks for water purifiers, among cylindrical drawing products. Under the same conditions, the thickness of the sidewall of the product formed by drawn experiment was studied. As a result of the experiment, the bottom thickness of stainless steel 304J1 was considered to be thick. It is judged that the defect rate can be reduced by changing the breaking phenomenon of the floor surface of the cold and hot water bottles to the material of stainless steel 304j1. Stainless steel 304 2B material shows a sharp change in thickness from punch corner R to sidewall position, while stainless steel 304J1 material showed a uniform change from punch corner R to sidewall position. Stainless steel 304J1 material is considered to improve the clamping of the product in the process of extracting the product after hand drawing. The appearance of stainless steel 3042B products is considered to produce more wrinkles in the flange, which exerts greater tensile force on the sidewall during molding, resulting in uneven sidewall thickness.

• 대한물리의학회지
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• 제16권1호
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• pp.73-81
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• 2021

PURPOSE: This study examined effects of the untact trunk stabilization exercise program on muscle thickness, trunk strength, maximal expiratory flow, and static balance. METHODS: The subjects were 20 normal adults divided into 10 in the contact exercise group and 10 in the untact exercise group. The trunk stabilization exercise program was conducted for four weeks. The muscle thickness was measured using ultrasound. The maximal expiratory flow was measured using Personal Best Full Range Peak Flow Meter. The static balance was measured through Bio-rescue; and the trunk muscle strength was measured by bending the upper body forward and measuring the time for maintaining the posture. RESULTS: Both contact and untact exercise groups showed significant differences in muscle thickness, muscle strength, maximal expiratory flow, and static balance (p < .05). A significant difference in muscle thickness on ultrasound was observed between the contact and untact exercise groups (p < .05). CONCLUSION: Activation of the transverse abdominal muscle requires accurate instructions of the contact exercise, but despite environmental constraints, the untact exercise program is as effective as the contact exercise for improving muscle strength, maximum expiratory flow, and static balance.

• 대한금속재료학회지
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• 제47권12호
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• pp.866-872
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• 2009

The effects of magnetic powder thickness on electromagnetic wave absorption characteristics in Fe-6.5Si-0.9Cr (wt%) alloy flakes/polymer composite sheets available for quasi-microwave band have been investigated. The atomized FeSiCr powders were milled by using attritor for 12, 24, and 36 h, powder thickness changed from $40{\mu}m$ to $3{\mu}m$ upon 36 h milling. The composite sheet, including thinned magnetic flakes, exhibited higher power loss in the GHz frequency range as compared with the sheets having thick flakes. Moreover, both the complex permeability and the loss factor increased with the decrease in thickness of the alloy flakes. Therefore, the enhanced power loss property of the sheets containing thin alloy flakes was attributed to the flakes of high complex permeability, especially their imaginary part. Additionally, the complex permittivity was also increased with the reduction of flake thickness, and this behavior was considered to be helpful for improvement of the electromagnetic wave absorption characteristics in the composite sheets, including thin alloy flakes.

• 국제물리치료학회지
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• 제12권2호
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• pp.2365-2369
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• 2021

Background: Patients with dysphagia after stroke are treated with neuromuscular electrical stimulation (NMES), but its effect on masseter muscle thickness and bite force in the oral phase is not well known. Objectives: To investigated the effect of NMES on masseter muscle thickness and occlusal force in patients with dysphagia after stroke. Design: Two group, pre-post design. Methods: In this study, 25 patients with dysphagia after stroke were recruited and allocated to either the experimental or the control groups. Patients in the experimental group were treated with NMES to the masseter muscle at the motor level for 30 minutes and were additionally treated with traditional swallowing rehabilitation for 30 minutes. In contrast, patients in the control group were only treated with traditional swallowing rehabilitation for 30 minutes. Masseter muscle thickness was measured using ultrasonography before and after intervention, and bite force was measured using an bite force meter. Results: The experimental group showed significant improvement in masseter muscle thickness and bite force compared to the control group. Conclusion: NMES combined with traditional dysphagia rehabilitation is effective in improving masseter muscle thickness and bite force in patients with dysphagia after stroke.

• 한국전기전자재료학회논문지
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• 제34권2호
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• pp.142-147
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• 2021

We present a subthreshold swing model for a symmetric junctionless double gate MOSFET. The scale length λ1 required to obtain the potential distribution using the Poisson's equation is a criterion for analyzing the short channel effect by an analytical model. In general, if the channel length Lg satisfies Lg > 1.5λ1, it is known that the analytical model can be sufficiently used to analyze short channel effects. The scale length varies depending on the channel and oxide thickness as well as the dielectric constant of the channel and the oxide film. In this paper, we obtain the scale length for a constant permittivity (silicon and silicon dioxide), and derive the relationship between the scale length and the channel length satisfying the error range within 5%, compared with a numerical method. As a result, when the thickness of the oxide film is reduced to 1 nm, even in the case of Lg < λ1, the analytical subthreshold swing model proposed in this paper is observed to satisfy the error range of 5%. However, if the oxide thickness is increased to 3 nm and the channel thickness decreased to 6 nm, the analytical model can be used only for the channel length of Lg > 1.8λ1.

• The Journal of Korean Physical Therapy
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• 제32권6호
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• pp.354-358
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• 2020

Purpose: This study aimed to verify the effects of bridge exercise with resistance to one hip joint adductor muscle on the thickness of external and internal oblique abdominal muscles, transversus abdominis muscle, and erector spinae muscle. Methods: The subjects were divided into two exercise groups: 15 for Bridge Exercise Group (BEG) and 15 for One Hip joint Adduction Bridge Exercise Group (OHABEG). The study used an ultrasonic instrument to measure trunk muscle thickness. OHABEG performed a bridge exercise with one hip Joint adduction. BEG performed a bridge exercise without resistance. Results: The external oblique abdominal, internal oblique abdominal, and the transversus abdominis muscles showed a significant increase by period and time in intra-group interactions (p<0.05), while there was no significant difference in inter-group changes (p>0.05). The erector spinae muscle had a significant increase in each period (p<0.05) but no significant difference in time, intra-group interactions, and in inter-group changes (p>0.05). Conclusion: These results demonstrated that bridge exercise with one hip joint adduction had positive effects on trunk muscle thickness. These results confirm that a bridge exercise with one hip joint adduction has a positive effect on the muscle thickness of trunk, suggesting the possibility of using it as a rehabilitation treatment for a lumbar stabilization exercise and as a basic data.

• Journal of the Korean Wood Science and Technology
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• 제32권3호
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• pp.71-78
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• 2004

The purpose of this study was to investigate the water absorption and thickness swelling of biocomposites at room temperature. These properties of bio-composites mainly depend on the ability of the agro-flour to absorb water through hydrogen bonding between water and the hydroxyl groups of the holocellulose and lignin in the cell wall. As the content of agro-flour increased, the water absorption and thickness swelling of the bio-composites increased. The effects of agro-flour content and rice husk flour (RHF) particle size on the water absorption and thickness swelling of the bio-composites were evaluated. In general, wood-based materials showed significantly higher water absorption and thickness swelling than the bio-composites. This might be attributed to the ability of the polybutylene succinate (PBS) hydrophobic polymer to prohibit the water absorption and thickness swelling of the bio-composites, Therefore, the use of agro-flour filled PBS bio-composites, which exhibit improved dimensional stability in comparison with wood-based materials, is recommended.

• Smart Structures and Systems
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• 제32권2호
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• pp.123-133
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• 2023

This paper proposes a thermography-based coating thickness estimation method for steel structures using model-agnostic meta-learning. In the proposed method, a halogen lamp generates heat energy on the coating surface of a steel structure, and the resulting heat responses are measured using an infrared (IR) camera. The measured heat responses are then analyzed using model-agnostic meta-learning to estimate the coating thickness, which is visualized throughout the inspection surface of the steel structure. Current coating thickness estimation methods rely on point measurement and their inspection area is limited to a single point, whereas the proposed method can inspect a larger area with higher accuracy. In contrast to previous ANN-based methods, which require a large amount of data for training and validation, the proposed method can estimate the coating thickness using only 10- pixel points for each material. In addition, the proposed model has broader applicability than previous methods, allowing it to be applied to various materials after meta-training. The performance of the proposed method was validated using laboratory-scale and field tests with different coating materials; the results demonstrated that the error of the proposed method was less than 5% when estimating coating thicknesses ranging from 40 to 500 ㎛.

• 한국진공학회지
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• 제6권S1호
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• pp.70-74
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• 1997

The study of the thickness dependence of the electron energy structure of Fe, Ni, Ti and Zr sublayers in Ni/Ti and Fe/Zr multilayers by using the experimental and computer simulated optical spectroscopy has been performed. A series of Ni/Ti and Fe/Ze multiayered films (MLF) with a bilayer period of 0.5 - 30 nm and constant (Ni/Ti) / different (Fe/Zr) sublayer thickness ratios were prepared by using computer-controlled double-pair target face-to-face sputtering onto a glass substrate at room temperature (RT) Computer simulation of the resulting optical properties of these MLF was carried out by solving of multireflection problem with a matrix method assuming either "sharp" interfaces resulting in rectangular depth profiles of the components or "mixed" (alloy-like) interfaces of variable thickness between pure-metal sublayers. Optical constants of pure bulk metals as well as equiatomic alloy interfaces were employed in these simulations. It was shown that the difference between experimental and simulated optical properties of the investigated MLF increases with decrease in sublayer thickness. This result allows to conclude that the electronic structures of sublayers below 4-5 nm thickness in mlf differ from the corresponding bulk metals.ponding bulk metals.

• 대한중풍순환신경학회지
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• 제15권1호
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• pp.29-38
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• 2014

■ Objectives The purpose of this study was to investigate the correlation of The Korean Standard Pattern Identification for Stroke and Intima-Media Thickness of common carotid artery(CCA-IMT). ■ Methods 100 subjects with acute ischemic stroke were recruited from the patients admitted to DongEui Medical Center from the June 2011 to January 2014. We assessed 100 patient's Common Carotid Intima Media Thickness data by B Mode ultrasonography. We investigated pattern identification of all subjects based on Korean Standard Pattern Identification for Stroke-III. then, We analyzed their characteristics, risk factor, blood test result, life style. ■ Results We analyzed indicators of Korean Standard Pattern Identification for Stroke-III by Common Carotid Intima Media Thickness difference. As a result, pale complexion, look powerless, drowsiness like to lie, heat vexation and aversion to heat were significantly higher in the CCAIMT ≧ 1.0mm group then in the CCA-IMT < 1.0mm group. ■ Conclusion According to the analysis, the Relationship between Carotid Intima-Media Thickness and The Korean Standard Pattern Identification for Stroke in Ischemic Stroke Patients were founded. To acquire more concrete conclusion on this theme, we need more research.