• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.4
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• pp.346-351
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• 1997

The pin bearing strength is one of the most important design parameters for mechanical joints composed of fiber reinforced composites. Thus the effect of the edge distance and the width of specimen on the pin-bearing strength of unidirectional CFRP composites were experimentally investigated in this paper. As results, the failure modes and the pin bearing strength of mechanical joints turned out to depend on the edge distance and also the width of specimen. The failure of specimen with low ratio of width to hole diameter was caused by the net tension from the hole boundary, on the other hand, the failure of specimen with low ratio of edge distance to hole diameter was caused by the shear-out. The bearing strength in case of the failure by shear-out was quite lower than that in case of failure by net tension.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2349-2351
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• 1999

In this paper, the variable absorption rates and DC dielectric breakdown strength of epoxy composites were measured at boiling absorption condition in order to observe the influences of moisture in out door use. Also, in order to improve withstand voltage properties at moisture absorbtion condition. IPN (interpenetrating polymer network) method which had been already reported, was introduced and the influence was investigated. As a result, it was confirmed that the moisture absorption rate was increased and DC dielectric breakdown strength was degraded with boiling time and filler content increasing. On the other hand, it was confirmed that moisture absorption rate and DC dielectric breakdown strength degrading rate were lowered by the improvement of adhesion strength In IPN specimens.

• Journal of Magnetics
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• v.16 no.4
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• pp.427-430
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• 2011

The rolled steels for welded structure applied tensile stress have been examined by means of magnetic Barkhausen noise (MBN) method and of a physical parameter obtained from a hysteresis loop. The behaviors of MBN parameters and coercive force with tensile stress were discussed in relation to microstructure changes. There is no change in MBN parameters and coercive force below yield strength. The coercive force rises rapidly with tensile stress above yield strength. On the other hand, the rms voltage and the peak in averaged rms voltage take a maximum around yield strength and then decreases. The magnetomotive force at peak in the averaged rms voltage shows a minimum around yield strength. These phenomena are attributed to the combined effects of cell texture and dislocation density. In addition, the behaviors of MBN parameters around yield strength may be reflected by the localized changes in strain field due to the formation of dislocation tangles.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.5 s.113
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• pp.63-69
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• 2005

This study was performed to introduce recently developed polyvinylamine as a wet-end process and paper strength improving aids. As a retention and drainage aids, high cationic charged polyvinylamine was more effective at the BCTMP and ONP stock condition than LBKP stock condition. As a dry tensile strength aid, dual system of polyvinylamine with anionic polyacrylamide was the best at the LBKP or ONP stock conditions. On the other hand, polyvinyl amine alone was better than dual system of polyvinylamine with anionic polyacrylamide at the BCTMP condition. As a wet tensile strength aid, polyvinylamine single system and dual system of polyvinylamine with anionic polyacrylamide were good at LBKP, BCTMP and ONP stock conditions. However, poly(aminoamide)-epichlorohydrin resin was good at LBKP and ONP stock conditions but efficiency of poly(aminoamide)-epichlorohydrin resin was remarkably decreased at BCTMP stock condition.

• Journal of the Korean Home Economics Association
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• v.9 no.2
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• pp.40-47
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• 1971

The purpose of this study was to examine the effects of several methods of the patching on the strength of the seam-texture. The main findings warranted from the present study were as follows : 1. The breaking strength was increased in proportion to the number of stitches in the case of 5 stitches per cm and 7 stitches per cm, not in the case of 9 stitches per cm where the tendency to damage the texture stitches appeared because of the excessive. 2. In comparing the effects of three methods (1. attaching a single patch, 2. attaching a single patch and seaming, 3. attaching several ply patch), no significant difference was found among these three. 3. There was a significant difference between the effects of two methods (1. attaching a single patch and stitching one edge of it on one side of the seam, 2. attaching a single patch and stitching both edges of it on the both sides of seam). In other words, the latter was found to be significantly more effective than the former. 4. In the case of unbalanced texture 9for example, single to two ply, single ply to two ply, or single to three ply), attaching a single patch to single ply and stitching both edges of it, and attaching a single patch to cover the plain-seam and stitching both edges of it, were more effective than attaching a single patch without stitching. 5. In comparing the effects of stitching both edges of the patch in 4 stitches per cm by the machine and by the hand, no significant difference was found. But these were more effective than stitching its both edges in 2 stitches per cm by hand. 6. The plain-seam stitched one edge of patch in 2 stitches per cm by machine and other by hand was significantly stronger than the plain-seam without a patch or with patch not stitched.

• 한국체육학회지인문사회과학편
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• v.57 no.5
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• pp.269-279
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• 2018

The purpose of this study is to examine the association between resistance exercise frequency, muscular strength, and health-related quality of life in Korean cancer patients. We performed complex sample general linear model and logistic regression analysis using data from a total of 647 cancer patients in the 2014~2016 Korean National Health and Nutrition Examination Survey (KNHANES). Participants who were participating in resistance exercise 0~1 day per week had lower EQ-5D index (0.852±0.016 vs. 0.890±0.020; p=0.006) and a significantly higher risk of having problems in mobility (Odd ratio[OR]=4.07; 95% confidence interval [CI]=1.31-12.63) compared to those who were participating in resistance exercise ≥ 5 days per week. Participants with low hand-grip strength had lower EQ-5D index (0.850±0.018 vs. 0.911±0.016; p<0.001) and a significantly higher risk of having problems in mobility (OR=4.94, 95% CI=2.14-11.41), usual activities (OR=5.18, 95% CI=1.56-17.14), and pain/discomfort (OR=2.46, 95% CI=1.33-4.55) compared to those with high hand-grip strength. This study showed that resistance exercise frequency and muscular strength were associated with health-related quality of life in Korean cancer patients.

• Physical Therapy Rehabilitation Science
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• v.2 no.1
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• pp.1-6
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• 2013

Objective: The aim of this review is to explore the latest intervention trends and effects of EMG-triggered functional electrical stimulation on the upper extremity functions in stroke patients. Design: Systematic review on clinical trials. Methods: A systematic literature search was performed to identify clinical trials evaluating the effects of EMG-triggered functional electrical stimulation (EMG-FES) and task-oriented EMG-triggered FES on the hand functions in stroke patients. Literature review was conducted with the following key words: hand function, functional electrical stimulation, task-oriented, stroke. Results: Ten clinical trials were included; 8 of them were randomized controlled trial, 1 was block-randomized, and 1 was a pre-post comparison study. A positive effect of electrical stimulation was reported in the patient groups that were treated with functional electrical stimulation combined with specific tasks, and volitional muscle contraction-triggered stimulation that was synchronized with tasks. Motor capabilities of the hand and arm were improved after the rehabilitation. Conclusions: EMG-triggered electrical stimulation may be more effective than non-triggered electrical stimulation in facilitating the hand functions in stroke patients in terms of muscle strength and voluntary muscle contraction of the paretic hand and arm. Triggered electrical stimulation can be even more effective when it is combined with specific tasks.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.1
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• pp.95-104
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• 2020

PURPOSE: A prospective study was conducted to investigate the correlation between the inspiration ability, bone mineral density, lumbar muscle strength, and muscular endurance for the national softball athletes in the national training center. METHODS: The general characteristics of study subjects, inspiration ability, bone mineral density, muscle strength, and muscular endurance data were analyzed using descriptive statistics. In addition, the Pearson product moment correlation was performed to investigate the correlation between the inspiratory capacity, bone mineral density, muscle strength, and muscular endurance. RESULTS: The inspiration, flow rates, and volume were not correlated with the bone mass and bone mineral density. Inspiration and the flow rates and volume were not correlated with the bone mass and bone mineral density. On the other hand, inspiration was correlated with the Extensor muscles (r=.464, p=.006) at an angular velocity of 60°/s and the flexors (r=.463, p=.006) and extensor muscles (r=.615, p<.001) at an angular velocity of 180°/s. The flow rate was also correlated with the extensor muscles (r=.444, p=.009) at an angular velocity of 60°/s and with flexor muscles (r=.432, p=.011) and extensor muscles (r=.589, p<.001) at an angular velocity of 180°/s. Finally, the volume was correlated at the extensor muscles at an angular velocity of 180°/s (r=.534, p=.001). CONCLUSION: The correlation between the inspiratory capacity, bone mineral density, muscle strength, and muscular endurance of softball athletes did not correlate with the bone mass and bone density. On the other hand, the lumbar muscle strength increased with increasing inspiratory capacity.

• Economic and Environmental Geology
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• v.37 no.2
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• pp.235-244
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• 2004

The shear strength of deep-sea core sediments from the nofheast equatorial Pacific was measured in various conditions to ensure precision of results. The comparison items were 1) two different measuring systems (hand-held vane and motorized vane), 2) in different places of on-board immediately after collecting the core samples and on-land laboratories after storing these samples for three months in a cold room, 3) two different core samples from a multiple corer within a sampling station, and 4) four different measuring points (holes) from a core sample. In this experiment, the values of shear strength in deep-sea sediments show significant change with depth which increase toward the bottom of core. Also, the results of two cores recovered at the same station indicate that vertical variation of shear strength is mainly caused by the change of physical properties. They strongly support the fact that the difference of vue syrtem and/or experimental conditions are not major factor in the variation of geotechnical properties.

• Journal of the Korea Convergence Society
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• v.11 no.5
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• pp.81-86
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• 2020

The Purpose of this study is analysis characteristic of grasping power with each different shoulder horizontal angle. Twenty female university students with no shoulder dysfuction participated subject in three different positions of shoulder horizontal flexion with standing posture, shoulder 0° flexion, elbow 90° flexion, forearm 90° pronation, different positions is followed : shoulder 0° horizontal adduction shoulder 40° horizontal adduction, shoulder 40° horizontal abduction. The One-way repeated ANOVA test was used to determine the different in grip strength on three shoulder horizontal positions. On the average, in the hand grip strength, the horizontal neutral position is higher than horizontal adduction position with significant value. In particular, shoulder horizontal aduction was measured lowest grip strength between three positions.