• Structural Engineering and Mechanics
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• v.59 no.1
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• pp.133-151
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• 2016

Self-Compacting Concrete (SCC) has been originally developed in Japan to offset a growing shortage of skilled labors, is a highly workable concrete, which is not needed to any vibration or impact during casting. The utilizing of fibers in SCC improves the mechanical properties and durability of hardened concrete such as impact strength, flexural strength, and vulnerability to cracking. The purpose of this investigation is to determine the effect of steel fibers on mechanical performance of traditionally reinforced Self-Competing Concrete beams. In this study, two mixes Mix 1% and Mix 2% containing 1% and 2% volume friction of superplasticizer are considered. For each type of mixture, four different volume percentages of 60/30 (length/diameter) fibers of 0.0%, 1.0%, 1.5% and 2% were used. The mechanical properties were determined through compressive and flexural tests. According to the experimental test results, an increase in the steel fibers volume fraction in Mix 1% and Mix 2% improves compressive strength slightly but decreases the workability and other rheological properties of SCC. On the other hand, results revealed that flexural strength, energy absorption capacity and toughness are increased by increasing the steel fiber volume fraction. The results clearly show that the use of fibers improves the post-cracking behavior. The average spacing of between cracks decrease by increasing the fiber volume fraction. Furthermore, fibers increase the tensile strength by bridging actions through the cracks. Therefore, steel fibers increase the ductility and energy absorption capacity of RC elements subjected to flexure.

• PNF and Movement
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• v.13 no.3
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• pp.145-153
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• 2015

Purpose: The current study aims to identify the effects of proprioceptive neuromuscular facilitation (PNF) on pain and grip strength in patients with cervical herniated intervertebral disc (HIVD) and provide effective interventions for such patients. Methods: Included in this study were 20 subjects (10 men, 10 women) in their 30s-50s who had been diagnosed with cervical HIVD. Intervention methods included PNF neck patterns, dynamic reversal of antagonists, and a combination of isotonics. The visual analogue scale (VAS) was used to measure pain and dynamometers were used to measure grip strength. Results: After four weeks of muscle strengthening exercises, neck pain was significantly reduced, and hand grip strength significantly increased. Conclusion: PNF can be utilized as an effective intervention to reduce the pain of patients with cervical HIVD and to increase grip strength.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.4
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• pp.152-162
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• 1993

The purpose of this study is to investigate problems of residual bending strength and the impact damage experimentally when CFRP composite laminates are subjected to Foreign object damage. The specimens composed of four types of CR/EPOXY and a CF/PEEK composite laminates which involved difference of fiber stracking orientation and matrics. The result were summariged as follows : 1) It is found that both orthotropic and guasi-isotropic composite laminates are increasimg lineally between impact energy and damage delamination area. 2) Delamination devel- opment energy(mm$^{2}$J) OF cf/epoxy composite aminates is less than that of CF/PEEK. 3) When impact energy is applied to specimens within 3J, the residual strength of orthotropic is greater than guasi-isotropic composite laminates. On the other hand, it is predicted that residual bending strength of orthotropic composite laminates is less than that of quasi-isotropic when impact energy is more thaen 3J. 4) It is found in CF/PEEK that for the impact side compression, residual of bending strength versus impact energy is almost constant, while in case of impact side tension, residual bending strength is decreased rapidly near 1.2J. of impact energy due to the effect of delamination buckling.

• Particle and aerosol research
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• v.20 no.2
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• pp.57-68
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• 2024

A silicon carbide (SiC) ceramic filter is an effective component for hot flue gas cleaning because of its high collection efficiency, high thermal shock resistance, and excellent mechanical strength. The effect of molding pressure in the production of SiC granular ceramic filters, on the mechanical strength and filtration performance, was investigated in this work. It was found that the ceramic filters produced at molding pressures less than 20 MPa have low mechanical strength and that this result was caused by weak physical interaction among the ceramic powders due to defects and cracks. On the other hand, the filter quality factor(q_F), which represents filtration performance of filter media, decreased with increasing the molding pressure due to the drastic increase in pressure drop. Ceramic filter performance factor(q_FM), which is the manipulation of maximum mechanical strength and q_F, was introduced to consider both mechanical strength and filtration performance in this study. As a result, molding pressure of 30 MPa was desirable to produce a SiC granular ceramic filter based on q_FM.

• Journal of dental hygiene science
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• v.22 no.1
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• pp.37-43
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• 2022

Background: Among the health problems in old age, oral health is closely related to nutrition intake and digestion, so although it is an important factor in the well-being of the elderly along with general health, studies examining the relationship between oral health-related factors and grip strength of the elderly are insufficient. Therefore, this study intends to examine the relationship between oral health-related factors and grip strength, which are closely related to the general health of the elderly. Methods: This study used data from the 7th period of Korea National Health and Nutrition Survey (2016~2018) approved by the Research Ethics Review Committee of the Korea Centers for Disease Control and Prevention. Complex sample frequency analysis and descriptive statistics were performed, and general linear model analysis was performed to confirm the relationship between demographic characteristics, oral health -related factors and grip strength. The statistical analysis was performed using IBM SPSS Statistics for Windows, Version 23.0, and the significance test was based on type I error level of 0.05. Results: Grip strength was higher in the case of no discomfort than in the case of discomfort in relation to mastication discomfort and grip strength (B=0.927, p<0.001). In addition, the grip strength was decreased by 1.348 times when not using dental floss (p<0.001) and when not using mouth wash was 1.480 times (p<0.001). Conclusion: In this study, in the relationship between oral health-related factors and grip strength, grip strength was found to be high in the absence of mastication discomfort. and in the case of using dental floss and mouthwash the elderly showed high grip strength. Therefore, it is suggested to present a lifestyle to improve hand function and grip strength in the elderly and develop a program to increase grip strength and provide them at the same time during oral health education.

• Journal of Korean society of Dental Hygiene
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• v.19 no.5
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• pp.743-752
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• 2019

Objectives: Grip strength is a measure for assessing overall muscle strength, muscle mass, and nutritional status, and is a useful tool for early examination of a person's general health. Thus, this study analyzed the association between oral health-related factors and grip strength, using the 6th Korea National Health and Nutrition Examination Survey (KNHANES) data. Methods: Data were analyzed using the IBM SPSS version 25.0 (IBM Co., Armonk, NY, USA) software with a complex sampling analysis of stratified and clustered variables, all with weighted values, applied for every analysis conducted. From the 6th KNHANES data, a total of 26,101 people were selected as the study population. A complex sample generalized linear model analysis was performed for participants' sociodemographic characteristics, health status, use of oral care products, and factors such as adult mastication and speaking habits. Results: Grip strength was found to be higher among men compared to women. Grip strength was the highest in the 20-39 year old group. Furthermore, grip strength was statistically significantly higher among married and employed individuals, and in the right hand (p<0.001). Grip strength was statistically significantly higher among people who perceived themselves to have good health and among those who did not have health-related problems in the past two weeks (p<0.001). It was also higher among those who used interdental brushes and electronic toothbrushes (p<0.001), but decreased with greater discomfort in mastication and speaking among adults (p<0.05). Conclusions: Grip strength was found to be associated with oral health-related factors and therefore, these could be helpful tools in evaluating both general and subjective health statuses. In general, oral care products are small in size with oral care involving the use of hands and certain precise motions and actions to remove foreign substances in the oral cavity. As shown in the findings, grip strength declines with increased age and as a result, the use of oral care products should be strongly recommended in order to promote better general health.

• Journal of the Korean Society of Physical Medicine
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• v.4 no.3
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• pp.183-192
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• 2009

Purpose：This study was conducted to investigate whether modified CIMT with Kinesio-Taping on paretic upper limb effects upper limb function in stroke patients in comparison to those receiving only modified CIMT. Methods：20 out-patients with hemiplegia were randomly assigned to either an experimental or a control group. Both groups received modified CIMT during a 10-week period. Additionally, an experimental group received modified CIMT with Kinesio-Taping on paretic upper limb and trunk. Results：In Manual function test, Grip strength, Jebsen-Taylor hand function test, MAL(Motor Activity Log) and Functional independence measure (FIM) were significantly different at all intervals of the study period(0, 3, 6, 10-week) in the experimental and control groups(p<.05). Exceptionally there was no significant difference in Jebsen-Taylor hand function test between the experimental and control groups. Conclusion：These results suggest that modified CIMT with Kinesio-taping improve the upper limb function. And also increase usage of affected upper limb and assist in daily living activity more than only modified CIMT.

• Journal of Korean Academy of Nursing
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• v.35 no.5
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• pp.943-954
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• 2005

Purpose: The purpose of this study was to identity the effects of a health promotion program for rural elderly on health promotion lifestyle and health status. Method: The study was a nonequivalent control group pre-post experimental design. Data collection was performed from April 12th, 2003 to August 2nd, 2003. The subjects were selected at Mari Myun Geochang Gun in Korea. 44 elders were in the experimental group and 45 elders were in the control group. The 16-week health promotion program was given to the experimental group. Data was analyzed by descriptive statistics, $x^2$-test, t-test, and ANCOV A test with SPSS/Win 10.0 program. Result: The experimental group showed higher scores of a health promotion lifestyle and perceived health status than the control group. In addition, systolic BP, heart rate, body fat and glucose of the experimental group were lower than the control group. Waist flexibility, left hand grip power, back strength and leg strength of the experimental group were higher than the control group. However, there were no significant differences in diastolic BP, total cholesterol and right hand grip power between the two groups. Conclusion: This health promotion program for rural elderly can be recommended as an effective nursing intervention in rural communities.

• The Journal of Korean Physical Therapy
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• v.27 no.4
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• pp.275-280
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• 2015

Purpose: This study was conducted to investigate the effect of cigarette smoking on physical fitness (dominant hand grip power, dominant isokinetic leg muscle strength, abdominal muscle endurance, flexibility, cardiopulmonary endurance) and depression in patients with chronic low back pain. Methods: This study was a cross sectional study and subjects consisted of 60 young males with chronic low back pain. The subjects were allocated to two groups following a self-report survey: cigarette smoking group (n=25) or non-smoking group (n=35). Physical fitness (dominant hand grip power, dominant isokinetic leg muscle strength, abdominal muscle endurance, flexibility, cardiopulmonary endurance) were measured using objective methods and depression in patients with chronic low back pain was measured using the Korean version of center for epidemiologic studies depression (CES-D) scale. Results: The results of this study were as follows: In physical fitness, the cigarette smoking group showed a significant decrease in abdominal muscle endurance, flexibility, and cardiopulmonary endurance compared with the non-smoking group. Depression index (CES-D scale score) was significantly higher in the cigarette smoking group than in the non-smoking group. Conclusion: These results suggest that cigarette smoking had a negative effect on abdominal muscle endurance, flexibility, and cardiopulmonary endurance in patients with chronic low back pain. In addition, depression of patients with chronic low back pain was affected by cigarette smoking. Thus, we suggested that cigarette smoking may play a significant role in the deterioration of physical fitness and depression of chronic low back pain patients.

• Journal of Biosystems Engineering
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• v.27 no.6
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• pp.557-564
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• 2002

Corrugated board is an efficient low-cost structure material fur the boxes that are widely used for transporting, storing and distributing goods. Corrugated board is also considered as an orthotropic because the principal material directions are the same as in paperboard. The purpose of this study was to elucidate the principal design parameters of ventilating box through the FEA on the various types of ventilating hole. From the viewpoint of the stress distribution and stress level, the optimum pattern and location of the ventilating hole were vertically oblong, and symmetry position with a short distance to the right and left from the center of front and rear panel. And, the optimum location and pattern of hand hole were a short distance to the top from the center of both side panels, and modified shape to increase the radius of curvature of both side in horizontal oblong. In general, the optimum pattern and location of both the ventilating hole and hand hole based on the FEM analysis were well verified by experimental investigation. It is suggested that decrease in compressive strength of the box could be minimized in the same ventilating hole area under the condition of the length of major axis of ventilating hole is less than 1/4 of box length, the ratio of minor axis/major axis is 113.5∼l/2.5, and number of the ventilating holes is even and symmetrical.