• Journal of Digital Convergence
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• v.13 no.7
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• pp.373-380
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• 2015

This study which was conducted on male tennis player on one hand(OH) & two hand(TH) backhand stroke and how both motion differed on low extremity movement with each feature analyzed in detail, the result as follow. The motion of TH based on resultant velocity, appeared to be a higher than OH, which was important variable in determining the ball speed. Contrary to TH where the player minimized the motion in the lower body and finalized a stroke through the turn of the trunk as if sticking the ball closed to the body, OH was carried out such that the player appeared to chase the ball. Whereas in OH, the knee joint extension moment was not found to be larger than TH, the opposite result came out for abduction moment and internal rotation moment. In the case of hip joint, consisted of extension, abduction and internal rotation moment, the outcome emerged to be greater for TH with conspicuous difference in abduction moment. Flection moment for TH overwhelmed in TH though both adduction and external rotation moment brought about similar outcome for both strokes.

• Physical Therapy Korea
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• v.26 no.1
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• pp.8-18
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• 2019

Background: Numerous studies have used smartphone applications to measure the range of motion in different joints. In addition, studies measuring the active range of motion (AROM) of the craniocervical joint have revealed high reliability. However, the subjects in these studies were all healthy subjects. No study has yet been conducted to measure the inter-rater reliability for the AROM of the craniocervical joint in stroke patients. Objects: The purpose of this study was to investigate the inter-rater reliability of the AROM of the craniocervical joint using a smartphone. Methods: The participants included 21 subjects who had strokes (17 males and 4 females). Two raters evaluated six types of craniocervical AROM, including flexion, extension, lateral flexion to the hemiplegic side, lateral flexion to the non-hemiplegic side, rotation to the hemiplegic side, and rotation to the non-hemiplegic side, using a goniometer and a smartphone to investigate inter-rater reliability. The inter-rater reliability was analyzed by intraclass correlation coefficients (ICC). Results: The inter-rater reliability of the smartphone was good for extension, lateral flexion to the hemiplegic side, lateral flexion to the non-hemiplegic side, and rotation to the hemiplegic side [ICC(2,k)=.86~.88] and excellent for flexion [ICC(2,k)=.95]. The inter-rater reliability for rotation to the non-hemiplegic side was moderate [ICC(2,k)=.72]. Conclusion: These results suggest that the smartphone offers high inter-rater reliability for measurements of the craniocervical AROM in patients with stroke.

• The Journal of Korean Physical Therapy
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• v.30 no.4
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• pp.101-107
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• 2018

This study was conducted to evaluate the effectiveness of taping intervention in patients with stroke through a review analysis of taping interventions used to enhance physical function and activity in patients with stroke. We searched randomized controlled trials using electronic databases. We also manually reviewed sources to identify additional relevant studies. Taping intervention is an approach to treat individuals with impaired physical function and activity. Taping interventions affect body functions by providing increased muscle strength, proprioceptive sensation, and range of motion, as well as decreased rigidity and pain. Taping interventions also improve walking, balance and arm functions, such as physical activity. Taping intervention for patients with stroke has been shown to be highly effective and is therefore strongly recommended; however, it is suggested that it be further developed to improve its efficacy as an intervention method and to create additional taping methods.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.3
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• pp.1-8
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• 2001

The flow field inside a cylinder of four-valve Sl engine was investigated quantitatively using a three-dimensional Laser Doppler Velocimetry system, to determine how stroke changes affect the flow field. The purpose of this work was to develop quantitative methods which correlate in-cylinder flows to engine performance. For this study, the sane intake manifold, engine head, cylinder, and the piston were used to examine the flow characteristics in different strokes. Quantification of the flow field was done by calculating three major parameters which are believed to adequately characterize in cylinder motion. These quantities were TKE, tumble and swirl ratios. The LDV results reveal that flow patterns are similar, the flow velocities scale with piston speed but another parameters such as TKE, and tumble and swirl numbers are not the same for different stroke systems.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.5
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• pp.114-120
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• 2000

Friction forces of piston rings for a typical SI engine were independently measured while excluding the effects of cylinder pressure, oil starvation and piston secondary motion using a floating liner system. Friction patterns, represented by the measured friction forces, were classified into five frictional modes with regard to the combination of predominant lubrication regimes(boundary, mixed and hydrodynamic lubrication) and stroke regions(mid-stroke and dead centers). The modes were identified on the Stribeck diagram of the dimensionless bearing parameter and friction coefficients which were evaluated at the mid-stroke and at the dead centers. And the frictional modes were estimated to the full operation range. The compression rings behave in the mode where hydrodynamic lubrication is dominant at the mid-stroke and mixed lubrication is dominant at the dead centers under steady operating conditions. However, the oil control ring behave in the mode where mixed lubrication is dominant throughout the entire stroke.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.466-469
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• 1995

This paper presents a design and performance of the 6 D.O.F linear motion table with a magnetic bearing suspension. The linear positioning of the table with a 150mm stroke is driven by a brushless DC Linear motor and the other attitudes of the stage are controlled by the analog PD controller with magnetic bearing actuators. Each magnetic bearing unit which consists of 3 electromagnets, 3 capacitance probes and 3 backup bearings affords controlled forces by detecting the air gap between the probes and guideways. An integral type capacitance probe amplifier is equipped on the upper plate of the table so that the probe line to the probe amplifier can be shorter therefore the problems due to the stray capacitance and noise can be reduced. Form the pitch-yaw errormeasured by the autocollimator, the vertical and horizont straightness errors of the table are derived that they are maintained below 1.mu. m over 100mm stroke. The positioning accuracy of the linear motion is maintained below 2 .mu. m and the repeatability error is below 1 .mu. m

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.6
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• pp.148-156
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• 2008

This paper is the first of 2 companion papers which investigate in-cylinder swirl generation characteristics according to inlet valve angle. Two DOHC 4 valve engines, one has wide intake valve angle and the other has narrow valve angle, were used to compare the characteristics of swirl motion generation in the cylinder. One intake port was deactivated to induce swirl flow. A PIV (Particle Image Velocimetry) was applied to measure in-cylinder velocity field according to inlet valve angle during intake stroke. The results show that the stronger swirl motion is observed in wide valve angle engine at the early intake stage; however, the swirl motion is gradually distorted by the intake flow component passing through valve area near the cylinder wall as the stroke proceeds. The tumble motion also does so in wide angle. On the contrary, the swirl and tumble motions, which are not clear at the initial stage, become better and better arranged as the piston goes down and up again after bottom dead center.

• Journal of the Korea Computer Graphics Society
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• v.24 no.3
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• pp.93-100
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• 2018

This paper proposes a small-scale rehabilitation system that allows stroke patients to perform daily rehabilitation training in a virtual home. Stroke patients have limited activities of daily living due to paralysis, and there are many rehabilitation exercises for them to reproduce activities that take place in the house, such as turning lights on and off, door opening and closing, gas valve locking. In this paper, we have implemented a virtual home with the above mentioned daily rehabilitation training elements, by using virtual reality technology. We use Leap Motion, a hand motion recognition device, for rehabilitation of hands and fingers. It is expected that stroke patients can rehabilitate small muscles without having to visit the clinic with uncomfortable body, and will be able to get interesting rehabilitation training by avoiding monotony of existing rehabilitation tools.

• Korean Journal of Applied Biomechanics
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• v.22 no.1
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• pp.65-73
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• 2012

The purpose of this study was to identify the saddle to pedal length contributing to successful performance in kayak using a kayak ergometer. Ten male elite kayak players participated in this study. players were tested on the kayak ergometer which was varied saddle to pedal length by the knee flexion angle(90deg; 120deg; 150deg) to measure stroke frequency, paddling amplitude, joint angle, RoM and angular velocity, foot pressure and force, iEMG using the 3D motion system, foot pressure system and EMG wireless system. At a results, rowing at 120deg on knee flexion angle showed higher stroke frequency and paddling amplitude than other knee flexion angles. RoM at upper extremity showed not significant difference between knee flexion angles. But there were significant differences in thorax and pelvis rotation RoM, knee flexion-extension RoM in each condition. In addition, foot pressure, force and iEMG were significantly different in knee flexion angles. Study showed that changed of saddle to pedal length affected rowing performance kinds of stroke frequency, paddling amplitude. The most important thing, increased range of motion in pelvic and thorax has occurred by force that generated foot-bar to seat. Not only that, but it seems to be attributed to a technical adaptation developed to maximum rowing performance.

• Journal of the Korean Society of Physical Medicine
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• v.13 no.3
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• pp.91-97
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• 2018

PURPOSE: Stroke patients have reduced balance ability due to a lack of motion in the ankle joint. Elastic taping assists movement, and joint mobilization, a form of passive movement, enhances mobility. The purpose of this study was to determine the immediate effects on balance ability after anterior-to-posterior (A-P) talocrural joint mobilization combined with elastic taping in stroke patients. METHODS: Twenty stroke patients were divided into two groups: a joint mobilization with taping group (experimental group, n=10) and an elastic taping only group (control group, n=10). The experimental group underwent anteroposterior mobilization of the talus and elastic tape was applied to the calf and tibialis anterior muscles. The control group had elastic tape applied. Dynamic balanced abilities were assessed by using the BioRescue system. After 30 minutes of intervention, the forward, backward, left side, and right side sway areas ($mm^2$) were measured. RESULTS: Only the experimental group showed a significant increase in forward sway area after intervention. However, no significant differences were detected between the two groups. CONCLUSION: This study shows that A-P talocrural joint mobilization combined with elastic taping has a positive effect, producing an immediate increase in the forward balance ability of stroke patients. However, this study did not examine joint mobilization alone. In subsequent studies, it is necessary to examine the effect of joint mobilization only on balance in stroke patients.