• Proceedings of the Korean Information Science Society Conference
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• 2001.10b
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• pp.55-57
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• 2001

강화학습은 한 에이전트가 자신이 놓여진 환경으로부터의 보상을 최대화할 수 있는 최적의 행동 전략을 학습하는 것이다. 따라서 강화학습은 입력(상태)과 출력(행동)의 쌍으로 명확한 훈련 예들이 제공되는 교사 학습과는 다르다. 특히 Q-학습과 같은 비 모델 기반(model-free)의 강화학습은 사전에 환경에 대한 별다른 모델을 설정하거나 학습할 필요가 없으며 다양한 상태와 행동들을 충분히 자주 경험할 수만 있으면 최적의 행동전략에 도달할 수 있어 다양한 응용분야에 적용되고 있다. 하지만 실제 응용분야에서 Q-학습과 같은 강화학습이 겪는 최대의 문제는 큰 상태 공간을 갖는 문제의 경우에는 적절한 시간 내에 각 상태와 행동들에 대한 최적의 Q값에 수렴할 수 없어 효과를 거두기 어렵다는 점이다. 이런 문제점을 고려하여 본 논문에서는 로봇 축구 시뮬레이션 환경에서 각 선수 에이전트의 동적 위치 결정을 위해 효과적인 새로운 Q-학습 방법을 제안한다. 이 방법은 원래 문제의 상태공간을 몇 개의 작은 모듈들로 나누고 이들의 개별적인 Q-학습 결과를 단순히 결합하는 종래의 모듈화 Q-학습(Modular Q-Learning)을 개선하여, 보상에 끼친 각 모듈의 기여도에 따라 모듈들의 학습결과를 적응적으로 결합하는 방법이다. 이와 같은 적응적 중재에 기초한 모듈화 Q-학습법(Adaptive Mediation based Modular Q-Learning, AMMQL)은 종래의 모듈화 Q-학습법의 장점과 마찬가지로 큰 상태공간의 문제를 해결할 수 있을 뿐 아니라 보다 동적인 환경변화에 유연하게 적응하여 새로운 행동 전략을 학습할 수 있다는 장점을 추가로 가질 수 있다. 이러한 특성을 지닌 AMMQL 학습법은 로봇축구와 같이 끊임없이 실시간적으로 변화가 일어나는 다중 에이전트 환경에서 특히 높은 효과를 볼 수 있다. 본 논문에서는 AMMQL 학습방법의 개념을 소개하고, 로봇축구 에이전트의 동적 위치 결정을 위한 학습에 어떻게 이 학습방법을 적용할 수 있는지 세부 설계를 제시한다.

• The Journal of Korean Society for School & Community Health Education
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• v.10 no.2
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• pp.29-42
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• 2009

연구목적: 본 연구는 고교운동선수들의 스포츠상해(부상)현황 파악을 통한 사고 및 손상예방을 목적으로 개발된 손상감시프로그램을 설명하고, 1년간 수집된 자료를 보고하기 위하여 수행되었다. 연구방법: 본 연구는 미국 플로리다주 내의 10개 고등학교에 재학 중인 학생 운동선수들의 스포츠상해(부상)에 대한 세부내용(사고경위, 상해부위, 사고 당시 환경적 요소 등)을 수집하여 이루어졌다. 학생 운동선수들에게 발생한 스포츠상해 조사 및 보고는 2007년에서 2008년에 걸친 학기동안 각 학교에 배치된 운동트레이너(Certified Athletic Trainer)에 의해 이루어졌다. 연구결과: 조사기간 동안 10개 조사대상 고등학교에서 614건의 스포츠상해가 발생하였고, 연습 중 사고노출 비율(1,000회의 연습 중 1명의 선수가 상해를 입는 경우를 기준으로 함)에 있어서는 풋볼(Football)이 2.73을 기록해 가장 높은 상해율을 보였으며 여자축구(2.03)와 남자농구(1.67)가 그 뒤를 이었다. 실전경기 중 사고노출 비율(1,000회의 실전경기당 1명의 선수가 상해를 입는 경우를 기준으로 함)의 경우, 풋볼(Football)이 14.4, 여자농구가 9.96, 레슬링이 7.1을 기록하였다. 운동상해로 인한 증상은 염좌/삠(관절손상)이 가장 많았고, 가장 많이 다치는 신체부위는 발목, 무릎, 머리인 것으로 나타났다.

• Journal of Korean Orthopaedic Sports Medicine
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• v.7 no.1
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• pp.33-36
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• 2008

Purpose: The purpose of this study was to evaluate the mechanism of injury in the anterior cruciate ligament tears sustained in participation in soccer. Materials and methods: 50 patients whose knees were injured during playing soccer were enrolled in this study. The mean age was 27 years old, 47 were male and 3 female. 15 of them were either professional or amateur soccer players, the rest were non-professional. The injury mechanism was investigated by evaluation of the medical records or by telephone interview. Results: The injury mechanism involved contact injuries in 17 patients and non-contact in 33. 41 patients were bearing weight on the involved side at the time of injury, and 9 patients were not. In cases of contact injury, 9 of the 17 patients had sustained a valgus force to the knee, and 5 patients had varus force, 11 patients had their foot planted, and 6 did not. Among those patients with a planted foot, 3 patients were injured by the rotation of the thigh, 1 patient was injured by hyperextension, and there were no deceleration mechanism injuries. In non-contact injuries, 30 out of 33 patients had their foot planted at time of injury and only 3 patients did not. Of these 30 patients, 16 were injured by the rotation of thigh, 6 sustained a varus force on the knee joint and 5 had a valgus force, 5 were injured by hyperextension, and 2 by deceleration. 3 patients, who did not have their foot planted, were injured while kicking with the involved leg. Conclusions: For soccer players in this series, the most common mechanisms resulting in anterior cruciate ligament tears were non-contact, most often by rotation of the torso over a planted foot. In contact injuries, the most common mechanism was the application of valgus force by tackle.

• Journal of Broadcast Engineering
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• v.11 no.2 s.31
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• pp.207-221
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• 2006

A fully automatic and computationally efficient method is proposed for intelligent display of soccer video on small multimedia mobile devices. The rapid progress of the multimedia signal processing has contributed to the extensive use of multimedia devices with a small LCD panel. With these emerging small mobile devices, the video sequences captured for standard- or HDTV broadcasting may give the small-display-viewers uncomfortable experiences in understanding what is happening in a scene. For instance, in a soccer video sequence taken by a long-shot camera technique, the tiny objects (e.g., soccer ball and players) may not be clearly viewed on the small LCD panel. Thus, an intelligent display technique is needed for small-display-viewers. To this end, one of the key technologies is to determine region of interest (ROI), which is a part of the scene that viewers pay more attention to than other regions. In this paper, the focus is on soccer video display for mobile devices. Instead of taking visual saliency into account, we take domain-specific approach to exploit the characteristics of the soccer video. The proposed scheme includes three modules; ground color learning, shot classification, and ROI determination. The experimental results show the propose scheme is capable of intelligent video display on mobile devices.

• Korean Journal of Applied Biomechanics
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• v.17 no.2
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• pp.131-143
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• 2007

In this study, we are concluded like this : 5 men who are soccer player of P university in B city measure the Electromyography with an angle of motion according to kinesiotaping's application when practicing in-step kick. When exercising in-step kick, the change of realization of muscle load of lower limbs enhence Gastrocnemius Lateralis and Vastus Medialis in the section of backswing, and improve Tibialis Anterior, Vastus Medialis, Rectus Femoris prior to impact after back-swing. Before impact, it mainly impoved Tibialis Anterior, Vastus Medialis, Rectus Femoris. After impact, it generally improved Gastrocnemius Lateralis, Vastus Medialis. Average integral electromyography value, it was such a small difference(; the difference of the value in Tibialis Anterior, Rectus Femoris, Vastus Medialis) that we can't compare case of after taping than before. In Electromyography, in case of after taping was considerably decreased at Gastrocnemius Lateralis, there was statistically significant difference between before and after. It was a little increased, after taping than before at Knee angle. And degree was a little decreased at Ankle angle. But, It's so delicate difference, there was not statistically significant difference between before and after.

• Journal of Nutrition and Health
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• v.36 no.7
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• pp.729-735
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• 2003

This study was performed to evaluate the effect of iron supplement for 4 weeks on iron status, immunity, and antioxidant status of national female soccer players (n = 25). This study was performed at summer hard training period right before competition. A single blind design was used to divide the subjects into iron-supplement (IS) or placebo group (P). Iron-supplement group was supplemented with iron (40 mg/d) for 4 weeks. The mean age of the subjects was 23.3 $\pm$ 2.5 years old. Mean height and body weight of the subjects were 164.4 $\pm$ 5.7 em and 57.4 $\pm$ 4.6 kg, respectively. The mean carrier as soccer player was 11.0 $\pm$ 2.6 years and mean training time was 7.0 $\pm$ 1.3 hr/day. The mean hemoglobin, hematocrit, total iron binding capacity and ferritin concentrations before iron supplementation were not different between two groups. After 4 weeks of summer training and iron supplementation, serum ferritin level was significantly increased only in IS group after supplementation. Mean corpuscular volume and total iron binding capacity were significantly decreased in both groups. Meanwhile, hemoglobin and red blood cell count were significantly lowered only in placebo group. The IgM concentration increased significantly in both groups, but IgG concentration had increasing tendency only in IS group (p < 0.064). Therefore, iron supplementation during hard training period may be helpful to improve work capacity of the athletes by improving ferritin status and humoral immune responses.

• Journal of the Korean Society of Physical Medicine
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• v.13 no.2
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• pp.157-165
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• 2018

PURPOSE: The purpose of this study was carried out to investigate the effect of plyometric training combined with core strength training on the balance and agility of adolescent soccer players. METHODS: A total of 36 subjects participated in this study. Subjects were randomly divided 3 groups and assigned PG (plyometric training group), CSG (core strength training group) and PCG (plyometric training combined with core strength training group). Each group was assigned to 12. Intervention was performed three times a week for 4 weeks. The training was performed for 60 minutes a day. Subjects were warmed up for 10 minutes, and performed main exercise for 40 minutes. Finally, subjects performed cool-down exercise including stretching for 10 minutes. A Statistical analysis was performed the paired t-test for the comparison pre and post intervention. A comparison among the groups was using one-way ANOVA, and the LSD was used for the post-test. RESULTS: The balance and agility were statistically significant differences in all group (p<.05). There was no significant difference in the balance factors between the three groups, but there was a significant difference in the agility factor (p<.05). CONCLUSION: Plyometric training and plyometric training combined with core strength training were effective for the balance and agility of adolescent soccer players.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.4
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• pp.273-282
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• 2019

Purpose : The purpose of this study was to provide the effective method for exercise therapy in soccer player. Methods : 30 soccer players were recruited for subjects. The subjects were divided to dynamic stretching exercise combined tDCS (Group I), dynamic stretching exercise combined Sham-tDCS (Group II) of which 15 subjects were randomly allocated. The subjects were given 3 hour of soccer skill and performance and additionally given 20 minutes of dynamic stretching exercise combined tDCS and sham-tDCS for each group, five times a week, for 6 weeks. Their muscle activity and jump performance were analyzed before the intervention. After 6 weeks of the intervention, the mentioned parameters were measured once more for between-group analysis. Results : Comparative analysis of the muscle activity and jump performance between the groups I and groups II showed statistically significant difference. Conclusion : Such results revealed that dynamic stretching exercise combined with tDCS is effective in muscle activity and jump performance. Based on the current study, more effective program is to be proposed for neurologic and musculoskelectal disorder as well as soccer player. Based on the current study, studies that incorporates various combine of variable is required for development of effective tDCS program.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.10 no.1
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• pp.45-52
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• 2012

Purpose : This study is carried out to investigate the effect of asymmetric exercises on soccer players' vertebral abnormality and weight bearing. Methods : A total of 40 soccer players were divided into either a group of 20 players who use a unilateral foot or a group of 20 players who use both feet. 3-dimensional spine structure analyzer was used to analyze body inclination, pelvic inclination, pelvic torsion, turning of spinal segment, spinal curvature, thoracic kyphosis curvature, lumbar lordosis curvature, left/right weight distribution, and front/back weight distribution. Results : The result of the two groups showed that there were significant differences (p<0.05) for every item except turning of spinal segment and lumbar lordosis curvature. Conclusion : From this result, we can find that spinal and pelvic deformity and body weight are unilaterally supported for soccer players with asymmetric exercises.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.5 no.1
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• pp.11-22
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• 2010

Object: This study was planned to show the physical characteristics of soccer player and their Yangdorak measurements. Method: We categorized 5 study group. (I-Players classified by age; II, III-Players and control group; IV-Players who had positive RF and the others; V-Players who had digestive disorder and the others) And We conducted the potentiality of skin resistance(Yangdorak) and GFS, PFT, ECG and the other, then analysis that. Result: As old aged group, Yangdorak shown lower RS, but that was not significant. Player group had higher Yangdorak score at H5, F1, F2, F5 than control group. Player group was shown better cardiopulmonary function, but H1, H2, H3 score were not significant. Players who conducted RF test shown not significant difference of H4 measurement between positive and negative group. Digestive disorder group had higher F1, F6 score, but that wasn't significant.