• Tribology and Lubricants
• /
• v.24 no.5
• /
• pp.215-220
• /
• 2008

An internal friction model was developed to model the frictional behavior of automotive Constant Velocity (CV) joints by using the test data from an instrumented CV joint friction apparatus with actual driveshaft assemblies. Experiments were conduced under different realistic operating conditions of oscillatory speeds, CV joint articulation angles, lubrication, and torque. The experimental data were used to develop a physics-based semi-empirical CV joint internal friction coefficient model as a function of different CV Joint operating parameters. It was found that the proposed friction model captures the experimental results well not only the static behavior of friction coefficient, but also the dynamic friction terms, which is the main source of force that causes vehicle vibration problems.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2012.10a
• /
• pp.393-394
• /
• 2012

• Journal of Educational Research in Mathematics
• /
• v.15 no.4
• /
• pp.419-444
• /
• 2005

As a theoretical background for this research, the literatures which focus on teaching and loaming of connecting with mathematics and science were investigated. And the rationale of integrated curriculum on the basis of the 7th mathematics curriculum and the goal of mathematics education and the forms of integrated curriculum and the integrated curriculum in foreign school were investigated. Depending on this review, the implement method of the integrated curriculum of mathematics and science in Korea school is suggested as the following: It requires designing inter-disciplinary into-grated problem or various teaching and learning materials which are based upon concept, skill, and principle by commonality found across the subject matter. Based on the analyses upon described above, three inter-disciplinary integrated teaching and learning materials were developed. And then, based on the case stud)', the research questions were analyzed in depth. Students could understand the developing process of linear function, develop the formula and grape representing the relationship between time and velocity, time and distance, and interpret realistic meaning of the slope.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.7
• /
• pp.1475-1482
• /
• 2009

In this paper, a computer simulation is developed for isotachophoretic protein separation in a serpentine micro channel for optimal lab on a chip design using 2D Finite Element Method. This 2D ITP model is composed of 5 components such as hydrochloric acid as Leader, caproic acid as terminator, acetic acid and benzoic acid as two proteins, and histindine as background electrolyte. The computer model is based on mass conservation equation for 5 components, charge conservation equation for electric potential, and electro neutrality condition for pH calculation. For the validation of the 2D spatial ITP model, the results are compared with the Simul5 developed by Bohuslav Gas Group. The simulation results are in a good agreement in a ID planar channel. This proves the precision of our model. The 2Dproteinseparation is conducted in a 2D curved channel for Lab on a chip design and dispersions of proteins are revealed during the electrophoretic process in a curved shape.

• Journal of Digital Convergence
• /
• v.17 no.6
• /
• pp.389-399
• /
• 2019

The purpose of this study was to investigate the effects of muscle asymmetry of knee joint among elite cyclists on anaerobic pedaling power related capacity. In another word, based on isokinetic strength of Non-Dominant, ND and Dominant, D, side, high, moderate and low ratio of ND to D were classified as High Symmetry Group, Moderate Symmetry Group and Asymmetry Group, respectively. Analysis of muscle asymmetry of extensor's ND and D side might not lead to any difference between the three groups. Based on muscle strength analysis of the flexor's ND and D, there was statistical difference between the groups in ND flexor and in the muscle balance index of the flexor muscle. This result also leads to significant difference in pedaling power functionality, but this effects might not lead to any negative pedaling power. Therefore, among even cyclists who may show almost the same recruitment pattern of ND and D side during pedaling stroke muscle asymmetry could exist but this phenomena might not negatively contribute to the pedaling capacity.

• Journal of the Korea Convergence Society
• /
• v.9 no.11
• /
• pp.465-477
• /
• 2018

The purpose of this study is to analyze the effect of three - week high altitude ski training on the myocardial performance of cross - country skiers and to provide basic data for the future improvement of cross - country skiers'. The subjects were 6 cross - country skiing male college athletes. To investigate the effects of periodic and high altitude training on cross - country skiers, a general linear model ANOVA with repeated measure And analyzed using the Paired Samples t-test. In high altitude ski training for 3 weeks, the body composition did not change but the isokinetic muscular function of the shoulder joint, hip joint, knee joint, and ankle joint was decreased. Therefore, further study is needed if it is considered that continuous strength training should be performed during the ski training period such as SP period.

• Journal of the Korean Applied Science and Technology
• /
• v.39 no.4
• /
• pp.527-534
• /
• 2022

The purpose of this study was to investigate the effects of 12 weeks of muscle power and agility training on physical fitness factors and isokinetic muscle function in elementary school male soccer players. For this purpose, 6 muscle power and agility training programs were organized for 12 elementary school male soccer players and were conducted 3 times a week for 12 weeks. The results of measurement and analysis of physical fitness factors before and after the muscle strength and agility training are as follows. First, there was a significant difference in the standing long jump in place of muscle power(p<.001). Second, there was a significant difference in the standing vertical jump of muscle power(p<.05). Third, there was a significant difference in the side step of agility(p<.01). As a result, 12 weeks of muscle power and agility training can be expected to have a positive effect on the improvement of agility and agility of elementary school male soccer players, and it is judged that it can provide training basic data for injury prevention and performance improvement.

• The Journal of the Korea Contents Association
• /
• v.6 no.12
• /
• pp.226-234
• /
• 2006

The aim of this study were to evaluate the effect of kinesio taping on isokinetic muscular function and pain of knee joint. The subjects for this study were twelve elderly women($65{\sim}70$years) suffered by knee joint pain over more than three years. The taping methods performed on 3 times a week for 8 weeks for improvement of isokinetic muscular function. Also, the change of visual analogue scale(VSA) and varval rating scale(VRA) has been measured before and post taping 8 weeks. Paired t-test was performed for data analysis at the 0.05 level of significance. After 8 weeks, the results of the study are as follow; First, peak torque, peak torque % BW, total work and ipsilateral balance ratio were significantly improved. And, work fatigue, visual analogue scale and verval rating scale were decreased significantly after 8 weeks taping. The results suggest that applying kinesio taping on knee joint may improve isokinetic muscular function of elderly women. Therefore kinesio taping method was effective for pain relief and prevention of knee joint pain in the elderly women.

• Journal of the Korean Applied Science and Technology
• /
• v.37 no.6
• /
• pp.1556-1566
• /
• 2020

The purpose of this study was to investigate the effect of Nurida-Ball exercise on isokinetic muscle function, spinal alignment, and dynamic balance capacity in middle-aged men. All middle-aged men(n=16) were divided into 2 groups: Ball exercise(BE, n=8) and control(CON, n=8) group. BE group performed the Nurida-Ball exercise(30 min/day, 3 days/week, 8 weeks) and isokinetic knee and trunk muscle function, spinal alignment, and dynamic balance capacity were measured. All of the measured variables calculated the mean and standard deviation and verified normality using the Shapiro-Wilk test. The independent t-test method and the Paired t-test method were then analyzed to identify differences between groups. This study found that isokinetic knee and trunk muscle function was significantly strengthened in the BE compared with CON group by increasing peak torque(PT) of right and left knee extension(60°/sec, p<0.01, respectively), average power(AP) of right and left knee extension(60°/sec, p<0.05, p<0.01, respectively), and PT of right knee flexion(180°/sec, p<0.05) and AP of right knee extension(180°/sec, p<0.05). In the change of isokinetic trunk muscle function, only PT of trunk extension(180°/sec) was increased in the BE compared with the CON group(p<0.05). In addition, Nurida-ball exercise can improve the spinal alignment by reducing the trunk inclination(p<0.05) in the BE compared with the CON group. Finally, dynamic balance capacity was also enhanced in the BE compared with the CON group by decreasing the score of overall balance index(OBI, p<0.01) and Antero-posterior balance index(p<0.05) in the Stage-6, and OBI(p<0.05) in the Stage-1. This result demonstrated that Nurida-ball exercise may improve spinal alignment, dynamic balance capacity, and isokinetic muscle function, which might be an effective way for the improvement of health-related fitness in middle-aged men.

• Science of Emotion and Sensibility
• /
• v.9 no.1
• /
• pp.1-7
• /
• 2006

The purpose of this study is to analyze the effects of the inhalation of 30% oxygen on heart rate and oxygen saturation ($SPO_2$) during cycle isokinetic exercise, in comparison with the inhalation of 21% oxygen. This study used oxygen supply equipment that can supply each of 21% and 30% oxygen constantly at a rate of 8 liter/min. Ten healthy male college students ($25.2{\pm}2.2$ years) participated in the experiment twice, one for 21% oxygen and the other for 30% oxygen. Each experiment was composed of three sections (a total of 18 minutes), which were composure (2 minutes), cycle isokinetic exercise at a speed of $20{\pm}1km/h$ (10 minutes) and recovery (6 minutes). 21% or 30% oxygen was supplied only during the sections of isokinetic exercise and restoration. Heart rate during isokinetic exercise and recovery was lower with the inhalation of 30% oxygen than with that of 20% oxygen but no difference was observed in $SPO_2$. $SPO_2$ was not different possibly because the same work load was applied to the group of 21% oxygen and that of 30% oxygen. Heart rate was reduced with the inhalation of 30% oxygen possibly because a larger quantity of oxygen was supplied at the same work load.