• Korean Journal of Applied Biomechanics
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• v.15 no.2
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• pp.11-20
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• 2005

This study has a purpose on contributing to apprehend safe and right way to stop to the inline skate beginners and to the instructors who teaches line skating on the basis for the result of the kinematical analysis on Heel brake stop movement of the inline skate, focusing on the displacement on COG, angle displacement of ankle joint, angle displacement of knee joint, angle displacement of hip joint, using a 3D image method by DLT. To achieve this goal, we analysed the kinematical factor of the 3 well-trained inline skating instructors and obtained the following results. 1. During the movement of heel-brake stop, when strong power was given to a stable and balanced stop and the lower limbs, if the physical centroid is lowered the stability increases, and if it is placed high from the base surface, as the stability decreases compared to the case of low physical centroid, we should make a stop by placing a physical centroid in the base surface and lowering the hight of physical centroid. 2. To make a stable and balanced stop and to provide a strong power to the lower limbs, it is advisable to make a stop by decreasing an angle displacement of ankle joint during a "down" movement. In case of the left ankle joint, in all events and phases the dorsiflexion angle showed a decrease. Nevertheless, in the case of the right ankle joint, the dorsiflexion angle shows an increase after a slight decrease. The dorsiflexion angle displacement of ankle joint can be diminished because of the brake pad of the rear axis frame of the right side inline skate by raising a toe, but cannot be more decreased if certain degree of an angle is made by a brake pad touching a ground surface. To provide a power to a brake pad, it is recommended to place a power by lowering a posture making the dorsiflexion angle of the left ankle joint relatively smaller than that of the right ankle. 3. To make a stable and balanced stop and to add a power to a brake pad, the power must be given to the lower limbs in lowering the hight of physical centroid. For this, it is recommended to make a down movement by decreasing the flexion angle of a knee joint and it is necessary to make a down movement by a regular decrease of the angle displacement of knee joint rather than a swift down movement in every event and phase. 4. The right angle displacement of hip joint is made by lowering vertically the hight of physical centroid as leaning slightly forward. If too narrow angle displacement of hip joint is made by leaning forward too much, the balance is lost during the stop by placing the center in front. To make a stable and balance stop and to place a strong power to the lower limbs, it is recommendable to make a narrow angle by lower the hip joint angle. However, excessive leaning of the upper body to make the angle too narrow, can cause an instable stop and loss of physical centroid. After this study, it is considered to assist the kinematical understanding during the heel brake stop movement of the inline skate, and, to present basic data in learning a method of stable and balanced stop for the inline skating beginners or for the inline skate instructors in the present situation of the complete absence of the study in inline skating.

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.51-63
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• 2002

This study sought to identify the kinematic characteristics at entrance to the straight course from the curvilinear course in the 200m-track game. For this purpose, this study was conducted for 4 sprinters by setting the 10m-section combined from the curvilenear track to the straight course and shooting them with the camcorder. It was set up to include all the sections of analysis by using the framework of the control point knowing the coordinate of the space and actual analysis was conducted on the motion showing the best records by conducting it for each subject five times. As a result, the following conclusion was drawn: It was found that the subjects showed the average stride of 4.5${\pm}$0.41 times at the 10-meter section and the required time of 1.42${\pm}$0.04sec. They showed the ratio average stride to height of 1.25${\pm}$0.20% and the average speed of 7.06${\pm}$0.19m/s. The displacement in the center of gravity of the human body at the section combined from the curvilinear course to the straight course was moving along the inward course of the curvilinear course, and the displacement of the leg located at the outward direction(right) was found to be larger than that of the leg located at the inward direction(left). In the speed of the left and right hand segments, it was found that the speed of the right hand located in the outward direction was faster than that of the left hand located at the inward, and it was found that the subjects progressed in the curvilinear course. The subjects showed the larger angle of the shoulder joint when the upper arm was located in the forward direction than when the it was located in the backward direction. In the curvilinear course, they showed the lower value of the lateral angle of the trunk when the right foot located at the outward direction left the ground than when the left foot located at the inward direction left the ground. And it was found that the lateral angle of the trunk became lower with approaching the straight course.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1185-1196
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• 2018

The purpose of this study was to investigate the effects of 12-week aquarobics exercise on blood lipids, atherogenic index, and liver functions in elderly women. The subjects for the study were 25 healthy elderly women volunteers, aged 65 to 80 years, composed of the aquarobics exercise group (n=13) and control group (n=12). Twice a week for 60 minutes for 12 weeks. The exercise intensity was set to RPE 11-12 for 1 week to 4 weeks, RPE 13-14 for 5 week to 8 weeks and RPE 15-16 for 9 week to 12 weeks respectively. The test data were analyzed by two-way repeated measures ANOVA, paired t-test, and independent t-test. The alpha level of .05 was set for all tests of significance. The results of the study in the aquarobics exercise group were as follows; LDL-C (p<.05), AST (p<.05) had significantly decreased, with TC (p<.01), TG (p<.05), LDL-C (p<.05), LDL-C/HDL-C (p<.05), TG/HDL-C (p<.05), AST (p<.001) significantly lower than control group. Consequently, these findings suggest that regular aquarobics exercise will be effective for preventiy the metabolic syndrome and cardiovascular health in elderly women.

• Journal of Korea Entertainment Industry Association
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• v.14 no.5
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• pp.131-146
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• 2020

This research is based on social flow that is in need of sports welfare that diagnoses the delivery system of sports program pass that is typical business of national sports welfare services and operation structure, and analyze the supplier, operator, beneficiary and all that is related to business from multilateral aspects, therefore seek for operation systems for provision systems of sports welfare services. To clearly grasp the operating mechanisms of service provision system that is happening in real field, there were in-depth interview done by the 18 people of suppliers, operators, and beneficiaries that are the main participants of business, and through which drew an ideal agreed point for sports welfare services to get in the right direction. The result of this study is as following: First, based on the limited government budget for the compilation of budget for the business of sports welfare services it is found that there is need of constructing a pragmatic service provision system that can bring maximum of efficiency. Second, voucher that was introduced for market logic application and greater transparency of the business of sports welfare services has a complex structure that it is in need of simplification of structure which that is well fit with its characteristics. Third, for convenience enlargement in administration and management, make management policy of provision system be reflected and therefore enlarge the independence of management and secure the power of negotiation regarding fee savings through centralized budget management.

• Journal of Digital Convergence
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• v.19 no.11
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• pp.575-583
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• 2021

This study aims to analyze Taekwondo trends according to news articles by year by applying topic modeling. In order to examine the Taekwondo trend through media reports, articles including news articles and Taekwondo specialized media articles were collected through Big Kinds of the Korea Press Foundation. The search period was divided into three sections: before 2000, 2001~2010, and 2011~2020. A total of 12,124 items were selected as research data. For topic analysis, pre-processing was performed, and topic analysis was performed using the LDA algorithm. In this case, python 3 was applied for all analysis. First, as a result of analyzing the topics of media articles by year, 'World' was the most common keyword before 2000. 'South and North Korea' was next common and 'Olympic' was the third commonest topic. From 2001 to 2010, 'World' was the most common topic, followed by 'Association' and 'World Taekwondo'. From 2011 to 2020, 'World', 'Demonstration', and 'Kukkiwon' was the most common topic in that order. Second, as a result of analyzing news articles before 2000 by topic modeling, topics were divided into two categories. Specifically, Topic 1 was selected as 'South-North Korea sports exchange' and Topic 2 was selected as 'Adoption of Olympic demonstration events'. Third, as a result of analyzing news articles from 2001 to 2010 by topic modeling, three topics were selected. Topic 1 was selected as 'Taekwondo Demonstration Performance and Corruption', Topic 2 was selected as 'Muju Taekwondo Park Creation', and Topic 3 was selected as 'World Taekwondo Festival'. Fourth, as a result of analyzing news articles from 2011 to 2020 by topic modeling, three topics were selected. Topic 1 was selected as 'Successful Hosting of the 2018 Pyeongchang Winter Olympics', Topic 2 was selected as 'North-South Korea Taekwondo Joint Demonstration Performance', and Topic 3 was selected as '2017 Muju World Taekwondo Championships'.

• Journal of Industrial Convergence
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• v.22 no.4
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• pp.21-29
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• 2024

This study analyzed the difficulty of scoring in different match situations in relation to which competitor scored first. The study analyzed the data from the 2022 Guadalajara World Taekwondo Championships. The analysis was performed for two separate weight classes: lightweight and heavyweight. Four game content variables were used: whether the athlete scored first, attack type, attack area, and game situation. Descriptive statistics, the Rasch model, and discrimination function questions were applied for data processing. SPSS and Winsteps were used for the statistical analysis, and the statistical significance level was set at 0.05. Consequently, in the lightweight class, the scoring frequency of the first scorer was high for all the game variables. In the heavyweight class, the scoring frequency for the first scorer was high for the attack type and attack area. By contrast, those who did not score first were more frequently found to be in a loss situation. By analyzing the scoring difficulties in different match situations based on whether the competitor scored first, the athletes who scored first in attack type most easily scored first. In losing situations, the athletes who scored first in attack area scored most easily, whereas those who did not score first scored most easily in body and match situations. For the heavyweight class, those who scored first in terms of attack type, counter-attack, and attack area scored the most easily while winning in body and match situations.

• Journal of Biosystems Engineering
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• v.34 no.2
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• pp.127-132
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• 2009

In the working population, muscle fatigue and musculoskeletal discomfort are common, which, in the case of insufficient recovery may lead to musculoskeletal pain. Workers suffering from musculoskeletal pains need to be rehabilitated for recovery. Isokinetic testing has been used in physical strengthening, rehabilitation and post-operative orthopedic surgery. Frequency analysis of electromyography (EMG) signals using the mean frequency (MNF) has been widely used to characterize muscle fatigue. During isokinetic contractions, EMG signals present strong nonstationarities. Hilbert-Haung transform (HHT) and autoregressive (AR) model have been known more suitable than Fourier or wavelet transform for nonstationary signals. Moreover, several analyses have been performed within each active phase during isokinetic contractions. Thus, the aims of this study were i) to determine which one was better suitable for the analysis of MNF between HHT and AR model during repetitive maximum isokinetic extensions and ii) to investigate whether the analysis could be repeated for sequential fixed epoch lengths. Seven healthy volunteers (five males and two females) performed isokinetic knee extensions at $60^{\circ}/s$ and $240^{\circ}/s$ until 50% of the maximum peak torque was reached. Surface EMG signals were recorded from the rectus femoris of the right thigh. An algorithm detecting the onset and offset of EMG signals was applied to extract each active phase of the muscle. Following the results, slopes from the least-square error linear regression of MNF values showed that muscle fatigue of all subjects occurred. The AR model is better suited than HHT for estimating MNF from nonstationary EMG signals during isokinetic knee extensions. Moreover, the linear regression can be extracted from MNF values calculated by sequential fixed epoch lengths (p> 0.0I).

• The Journal of Korean Physical Therapy
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• v.3 no.1
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• pp.39-58
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• 1991

This study was carried out to recognize the understanding of high school teachers about physical therapist during September in 1988, The study population was comprised of 511 high school teachers who had lived in Seoul and Kyunggi Province. Mate teachers were $56\%$ and the rest of them were females. In age distribution $45.4\%$ of them belonged to the 3rd decade, in religion $36.2\%$ of them were Christians, and in their carrier $45.8\%$ of them were less then 5 years. The results obtained were as follows. 1. The high school teachers who knew about department of physical therapy is amounted to $62.6\%$ in male and $49.8\%$ in female. The high school teachers ($41.7\%$ in male and $38.6\%$ in female) considered that students aptitude was the most important thing to keep in mind in counselling those who wished to become physical therapists. There were difference in opinion between male and female teachers as to the counselling criteria (p<0.05). 2. The high school teachers who knew that the students would beemployed in sport center and health clubs after graduation amounted to $24.3\%$ in males and in general hospital to $27.1\%$ in female. There was significant difference in the knowledge for their field of employment between male and female teachers (p<0.05). 3. As to the effectiveness of the physical therapy, $41.3\%$ of male and $29.8\%$ of the female teachers responded to 'satisfactory', but indicating no statistical difference both sexes. 4. As for the attitude of physical therapiest, $43\%$ of them answered that kindness and service devotion were the prerequisite for them. There were statistical difference between male and female teachers in concepts about attitude (p<0.05). To the social level of physical therapist, majority of the teachers thought that physical therapist belong to moderate level in social class. 5. Those who considered that the physical therapy was necessary means for treatment of trauma amounted to $73\%$. The reason why teachers thought that physical therapy was not necessary was that it required too long period of time for the treatment. 6. Those who knew fully the job of physical therapist amounted to $55\%$ and the 55. $9\%$ knew that physical therapists work only at hospitals as the therapist and the rest of them misunderstood the job of physical therapist. 7. As for the academic background to be qualified as physical therapist, $76.2\%$ of them said that graduation of Junior College was required, $12.9\%$ graduation of Senior College and the rest of them had no ideas at all. There was no statistical difference between male and female teachers.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.3
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• pp.119-125
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• 2010

We investigated the effects of a hot-water extract of Artemisia iwayomogi, a plant belonging to family Compositae, on cardiac ventricular delayed rectifier $K^+$ current ($I_K$) using the patch clamp technique. The carbohydrate fraction AIP1 dose-dependently increased the heart rate with an apparent $EC_{50}$ value of $56.1{\pm}5.5\;{\mu}g/ml$. Application of AIP1 reduced the action potential duration (APD) in concentration-dependent fashion by activating $I_K$ without significantly altering the resting membrane potential ($IC_{50}$ value of $APD_{50}$: $54.80{\pm}2.24$, $IC_{50}$ value of $APD_{90}$: $57.45{\pm}3.47\;{\mu}g/ml$). Based on the results, all experiments were performed with $50\;{\mu}g/ml$ of AIP1. Pre-treatment with the rapidly activating delayed rectifier $K^+$ current ($I_{Kr}$) inhibitor, E-4031 prolonged APD. However, additional application of AIP1 did not reduce APD. The inhibition of slowly activating delayed rectifier $K^+$ current ($I_{Ks}$) by chromanol 293B did not change the effect of AIP1. AIP1 did not significantly affect coronary arterial tone or ion channels, even at the highest concentration of AIP1. In summary, AIP1 reduces APD by activating $I_{Kr}$ but not $I_{Ks}$. These results suggest that the natural product AIP1 may provide an adjunctive therapy of long QT syndrome.

• Journal of Digital Convergence
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• v.11 no.6
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• pp.235-244
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• 2013

This research was performed to investigate the effects of participation in aqua exercise on blood composition and vascular compliance of mentally retarded persons. The targets of this research consisted of a control group of 12 people and an aqua exercise group of 12 people after selecting 24 mentally retarded males and aqua exercise group carried out an exercise program for 60 minutes per day and five days a week for 9 weeks. Weight, body fat percentage, blood composition and vascular compliance were measured in a preliminary inspection and the same items were measured in a post-inspection. The results of this measurement were as follows. Firstly, aqua exercise group showed a significant decrease in weight and body fat percentage (p<.05). Secondly, for blood composition, aqua exercise group showed a notable decrease in Total-Cholesterol, Triglyceride, and LDL-Cholesterol (p<.05) and a significant increase in HDL-Cholesterol (p<.05). Thirdly, aqua exercise group showed a notable increase in blood composition for both upper limbs and lower limbs (p<.05). Taken these results together, it was considered that a participation of mentally retarded persons in aqua exercise would prevent adult diseases and would have an affirmative influence on improvement of the quality of life.