• KSTLE International Journal
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• 제6권2호
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• pp.51-57
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• 2005

Surface texturing of tribological applications is an attractive technology of engineered surface. Therefore, reduction of friction is considered to be necessary for improved efficiency of machines. The current study investigated the potential of textured micro-scale grooves on bearing steel flat mated with pin-on-disk. We discuss reducing friction due to the influence of sliding direction at surface pattern. We can indicate lubrication mechanism as a Stribeck curve, which has a relationship between the friction coefficient and a dimensionless parameter for the lubrication condition. It was found that the friction coefficient was changed by the surface pattern and sliding direction, even when surface pattern was the same. It was thus verified that micro-scale grooves could affect the friction reduction considerably under mixed and hydrodynamic lubrication conditions. The lubrication regime influences the friction coefficient induced by the sliding direction of groove pattern. The friction coefficient depends on a combination of resistance force and hydrodynamic.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2008년도 춘계학술발표대회 논문집
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• pp.36-38
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• 2008

The purpose of the study is to propose a new surface design concepts within fractal pattern. In this study, I am offering the fractal concepts drawn from science, as a new anchoring point for surface design. Fractal Patterns are generated by transforming a seed slab into a number of constituent elements through fractal operations of rotation, scaling and linear transformations. These elements are bound together as a second generation seed shape which is reiterated according to the same transformations. This process continues for as many generations as desired. In conclusion, this study places a great emphasis on the natural pattern order to the surface generation, which I hope will contribute to generating a number of creative possibilities for interior design.

• 한국생활과학회지
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• 제19권6호
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• pp.1045-1052
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• 2010

Effects of the ease of pattern on the thermal conditions of clothing were investigated through the measurement of clothing surface temperatures using infrared thermography. Four vests with different pattern ease were worn by five male subjects. Surface temperature distribution on the clothing were then examined using a thermogram to view thermo-regulating characteristics affected by the ease of pattern. Representative surface temperatures were calculated based on the percentage of the surface area within a certain temperature range and the midpoint value of the corresponding area. Representative surface temperatures matches well to the thermal insulation value measured by thermal manikin. Results indicated that representative surface temperature could be a useful quantitative value if some simple calculations were to be used alongside accurate image processing.

• 한국기계가공학회지
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• 제10권3호
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• pp.94-99
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• 2011

Micro-scale surface pattern has an benefit of tribological application under lubricated sliding contact. Therefore, a special pattern, that has to reduce the coulomb friction under contact, is considered to be necessary for improved efficiency of machines. The current study investigated the friction property of angle effect for micro-scale grooved crosshatch pattern on bearing steel surface using pin-on-disk type. The samples fabricated by photolithography process and then these are carry out the electrochemical etching process. We discuss the friction property due to the influence of hatched-angle on contact surface. We could be explained the lubrication mechanism for a Stribeck curve. It was found that the friction coefficient depend on an angle of the crosshatch on contact surface. It was thus verified that micro-scale crosshatch grooved pattern could affect the friction reduction.

• 전기학회논문지P
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• 제65권3호
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• pp.224-234
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• 2016

This study developed the conductivity pattern of solid surface using laser direct pattern and compound polymer material technology. For development direct patterning system of solid surface, we used the laser power stabilizer, the dynamic focusing, 3D scanner S/W and the auto aligning techniques. Also For conductivity pattern, we are developed compound polymer material with additive by electro-less plating. These technologies are already used commercially. However operation and control integrated system for direct patterning of solid surface are not yet developed. The objective of this paper is to introduce the laser direct structuring for simple process improvement instead complex PCB process, and develop the operating stability and integration system. Also we implemented new application of laser direct structuring through sample manufacture.

• 복식문화연구
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• 제19권5호
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• pp.1049-1060
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• 2011

The purpose of this study was to develop a shirt pattern that enhances the functionality of golf swing motions. The pattern was made with 3D body surface shape data that changed according to dynamic golf postures. The data were collected from the golf swing motions. The 3D body surface data in golf swing postures piled up on the 3D surface data in a static posture. The results showed that the surface shape data changed more in the address, back swing, and finish postures than the other swing postures. The experimental pattern was developed with 3D surface scan data in those three golf swing motions. The pattern had raglan sleeves and the front-bodied piece was divided into two pieces with a princess line, which comes from armscye line of the address posture. The back bodice piece was divided into three pieces with a yoke line and a back princess line. The yoke line was made by back shoulder shape in the back swing posture. The level of comfort of the experimental garment and commercial golf shirts was evaluated by 38 women golfers. The experimental garment pattern was evaluated to be more comfortable in golf swing postures than commercial golf shirts.

• 국제물리치료학회지
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• 제11권2호
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• pp.2028-2035
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• 2020

Background: Weakness of the trunk muscles decreases the trunk control ability of stroke patients, which is significantly related to balance and gait. Objectives: To compare the impact of diagonal pattern self-exercise on an unstable surface and a stable surface for trunk rehabilitation on trunk control, balance, and gait ability in stroke patients. Design: Nonequivalent control group design. Methods: Twenty four participants were randomized into the experimental group (diagonal pattern self-exercise while sitting on an unstable surface, n=12) and the control group (diagonal pattern self-exercise while sitting on a stable surface, n=12). All interventions were conducted for 30 minutes, three times a week for four weeks, and the trunk impairment scale (TIS), berg balance scale (BBS), functional gait assessment (FGA), and G-walk were measured. Results: All groups indicated significant increases in all variables (TIS, BBS, FGA, cadence, speed, stride length) after four weeks. The TIS, BBS, FGA, cadence, gait speed, and stride length group-by-time were significantly different between the two groups. Conclusion: We found that, in stroke patients, diagonal pattern self-exercise on an unstable surface is a more effective method for improving trunk control, balance, and gait ability than diagonal pattern self-exercise on a stable surface.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.272-273
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• 2013

Some living thingsuse micro- or nano- structures for living in nature. Scientists and engineers made efforts to mimic them, and they succeeded in making new types of applications. They used 'Namib desert beetle' to self-filling device by moisture harvesting and 'lotus leaf' to self-cleaning device by water repelling. 'Namib desert beetle' and lotus leaf have micro-patterns on their surface, which consists of hydrophobic or hydrophilic materials [1]. Moreover, micro-patterns on the surface make self-filling or self-cleaning property enhanced because of the surface roughness. Surface roughness enhances wettability [2]. Micro-pattern is a significant factor to make the surface be functional, so we want to make new types of functional surface by micro-patterning. In this work,we make several functional micro-patterns (radial, line, and dot arrays) using maskless lithography and analyze the characteristics of each micro-pattern. In order to analyze and understand surface characteristics, micro-patterns with varying sizes are investigated. All experiments are proceeded on mr-DWL5 photo resists coated on silicon wafers in same condition. All the experiments have demonstrated good performances about hydrophobic or hydrophilic property corresponding to their material and structural combinations. In radial micro-pattern, although the surface is flat, water drops on hydrophilic radial pattern can be convergent to a middle point and water drops on hydrophobic radial pattern can be divergent from the middle point. In line array micro-pattern, water drops can roll off along only one direction in parallel with the line arrays. Such phenomena might be mainly caused by the local change of surface roughness. From these results, controlling the movement and direction of water drops is made feasible without introducing a slope, which can potentially be used for new types of applications.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 추계학술대회 논문집
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• pp.141-142
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• 2007

• 소성∙가공
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• 제22권1호
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• pp.36-41
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• 2013

The present study examines the micro-pattern replication on a plastic film using ultrasonic imprinting. Ultrasonic imprinting uses ultrasonic waves to generate repetitive microscale deformation in the polymer film. The resulting deformation heat on the surface of the film causes the surface region to soften sufficiently so that a replication of the micro-pattern can be obtained. To successfully replicate the micro-pattern on a large area of polymer film, a high replication ratio is needed as well as good uniformity over the entire region. In this study, a horn design is investigated by finite element analysis and is optimized through a response surface analysis. In the ultrasonic imprinting experiments, the response surface method was also used to determine the optimal processing conditions for better replication characteristics.