• 대한정형도수물리치료학회지
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• 제29권2호
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• pp.39-48
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• 2023

Background: The position of pitcher requires a lot of repetitive motion, and because of this, it is known that not only professional baseball players, but also middle and high school players are frequently exposed to injuries in baseball. The purpose of this study is to examine the differences in upper extremity muscle activity during repeated pitching and the activity of each muscle during repeated pitching by analyzing middle and high school pitchers, divided into groups by age. Methods: Twenty participants (10 middle school male students and 10 high school male students) were recruited for this research. The outcome measures included neuromuscular motor control, including the upper trapezius (UT), triceps brachii (TB), deltoid (DT), latissimus dorsi (LD), biceps brachii (BB), pectoralis major(PM), extensor carpi radialis(ER), and flexor carpi radialis (FR). Results: The two-way analysis of varaince (ANOVA) was used to compare the muscle activity variables between the middle school and high school students. The one-way ANOVA was used to compare the muscle activity variables within time differences each groups. Conclusion: Our results provided promising clinical evidence that guide for upper extremity muscles to increase pitching efficiency in middle and high school base ball players.

• 대한관절경학회지
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• 제12권2호
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• pp.134-138
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• 2008

견관절 상완순 전후방(SLAP: Superior labrum anterior to posterior) 병변은 상부 관절와순 단독 손상으로 발견되기도 하고, 견관절 재발성 탈구 환자에서 전하방 관절와순의 파열, 즉 Bankart 병변의 연장으로 상부 관절와순까지 파열이 진행된 동반 손상으로 발생하기도 하며, 드물게 후방 Bankart 병변을 동반하는 경우도 있다. 여러 가지 병변과 동반된 SLAP 병변이 보고되어 왔으나 그 중 후방 Bankart 병변과 동반하여 발생한 후방 II형 SLAP 병변에 대한 보고는 미미하고 그 병변에 대한 관절경적 복원술 시 봉합 나사(suture anchor)의 삽입과 봉합에 주의할 점이 있다. 저자들은 투구 동작과 같은 흔한 손상 기전이 아닌 팔을 뻗친 상태에서 넘어지면서 발생한 외상으로 야기된 본 증례에 대해 관절경적 복원술을 시행하여 만족할 만한 결과를 얻었기에 보고하는 바이다.

• 한국운동역학회지
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• 제12권1호
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• pp.173-191
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• 2002

The purpose of this study was defined efficient throw motion pattern to obtain the quantitative data and to achieve successful bowling through kinetic - kinematic variables on the throw motion. Subject of group composed of three groups : Higher bowlers who are two representative bowlers with 200 average points and one pro-bowler. Middle bowlers who are three common persons with 170 average points. Lower bowler who are three common persons with 150 average points. Motion analysis on throw motion in three groups respectively has been made through three-dimension cinematography using DLT method. Two high-speed video camera at operating 180 frame per secondary. One-way ANOVA has been used to define variable relations. Analyzed result and conclusion are the following : The displacement of back of the hand must have wider difference of each right-left displacement to increase the spin of the ball. In high bowlers group, difference between the front-rear position of back of the hand in case of success and that in case of failure in follow throw is 0.17m. That is to say, momentum in case of success come to increase greatly, compared with that in case of failure. To increase the spin of the ball, the potential difference should be narrower in follow through. In case of the high bowlers, the velocity of the front-rear direction of the back of the hand has been the fastest both in release and follow through, compared with those in other groups, which has contributed to increasing the spin force of the ball. The orders in the resultant velocity of the back of the hand has shown the this : the finger tip$\rightarrow$the back of the hand$\rightarrow$wrist.These orders made the proximal segment support the distal segment. The distal segment has provided the condition to accelerate the velocity. In case of failure, the suddenly increased velocity has caused the failure in the follow through. Acutely flexing the angle of the back of the hand has contributed to lifting to increase the spin of the ball.

• 대한정형외과스포츠의학회지
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• 제7권2호
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• pp.67-74
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• 2008

반복적으로 던지는 동작은 주관절에 심한 기계적인 스트레스를 주며, 주된 기전은 외반력이며 그 결과 내측 인장력과 외측 압박력, 후방부의 충돌현상이 발생한다. 성장기나 청년기에 지속적인 스트레스는 주관절에 해부학적 변화를 유발할 수 있다는 위험성을 운동선수와 가족, 코치들은 반드시 잘 이해하고 있어야 한다. 스포츠와 관련된 주관절 손상을 막기 위하여 적절한 운동법 교육, 워밍업, 의학적 전문 지식, 보호 장구 등이 필요하다. 또한 손상 예방과 재활은 적절한 투구 동작, 근력 강화, 견갑골에 대한 조절, 관절 운동 범위의 적절한 유지가 필수적이다.

• 한국운동역학회지
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• 제16권3호
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• pp.53-63
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• 2006

The general objective of this study was to investigate biomechanical characteristics of bowling swing using three-dimensional cinematography. This study focused specifically on movements of the upper body segments during a bowling swing. Eight elite female bowling players participated in this study. Subjects performed bowling swing and their performance was sampled at 60 frame/sec using two high-speed video cameras with a synchronizer. After digitizing images from two cameras, the two-dimensional coordinates were used to produce three-dimensional coordinates of the 12 body segments (20 joint reference makers). The obtained three-dimensional coordinates were fed to a custom-written kinematic and kinetic analyses program (LabView 6.1, National Instrument, Austin, TX, USA). The analyses determined the linear and angular kinematic variables of the body segments with which joint force and torque of the lower and upper trunks and the shoulder were estimated based on the Newton-Euler equations. It was found that during the bowling swing the peak linear velocities of the body segments were reached in sequence the trunk, the shoulder, the elbow, the wrist, and the bowl. This result indicates that linear momentum of the lower body and the trunk transmits to the arm segment during the bowling swing. The joint torques of the torso and the arm occurred almost simultaneously, indicating that bowling swing seem to be a push-like motion, rather than a proximal-distal sequence motion in which many of throwing motions are categorized. The ultimate objective of the bowling swing is to release a heavy-weight bowl with power and consistency. Therefore, the bowling swing observed in this study well agrees with that bowlers use the stepping to increase the linear velocity of the bowl, the simple pendulum system and the push-like segmental motion in the torso and the arm segment to enhance the power at the release of the bowl.

• 한국운동역학회지
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• 제16권3호
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• pp.33-41
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• 2006

This study was to analysis three dimension angle of the upper extremity segment and trunk to putting the protector in women bowlers. For this study, the subjects selected 4 players of national and university team. All subjects putted in the same wrist support to satisfy the experiment conditions. To get three dimensions position coordination of swing motion used for 6 ProReflex MCU 240 camera produced by Qualisys. After position coordination calculation, Three dimension angle of the trunk and the upper extremity segment calculated for Matlab 6.5. the result is following; In the trunk motion, there were little differences among the subjects in a flexion and extension change. There were a lot of differences in motion change of the abduction-adduction and internal-external rotation, but the motion types translated to the adduction-abduction-adduction and from the internal rotation toward the external rotation. In the upper arm segment the Flexion and extension showed a consistent motion in the down swing and up swing phase. And the motion change of abduction-adduction and pronation-supination showed a abduction-adduction-abduction and pronation-supination change during swing phase. In the forearm segment changes, it showed a lot of differences among the subjects and a similar change with the upper arm segment. Especially, the hand segment showed a supination motion from the backswing apex to release phase, but for increasing a rotation velocity of ball, the hand segment translated toward pronation in follow throw phase.

• 한국전자통신학회논문지
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• 제11권3호
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• pp.339-344
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• 2016

본 연구는 위성영상과 현장자료를 이용하여 순천만 조간대의 대형저서생물의 분포를 분석하기 위하여 수행되었다. 2010년 7월 7일 간조에 근접한 위성영상과 2010년 9월 25일 만조에 근접한 위성영상을 무감독분류를 이용하여 바다와 갯벌, 육지로 분류하였다. 분류된 영상에서 간조 때와 만조 때의 갯벌을 중첩시켜 조간대를 추출하였다. 조간대에서 총 출현 수는 196종이었으며 조하대 우측에서 가장 많은 종이 출현하였다. 투구갯지렁이류(Sigambra tentaculata)가 가장 우점 하였으며 버들갯지렁이류(Mediomastus californiensis, Heteromastus filiformis), 양손갯지렁이(Magelona japonica) 등이 출현하였다. 조상대에 비해 조하대에 많은 저서생물들이 분포하는 것을 파악하였다. 유기물에 강한 내성을 지닌 대형저서생물들의 분포를 통해 순천만 조하대 지역이 유기물로 인하여 오염 되었다고 판단된다.

• 복식
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• 제58권5호
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• pp.166-177
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• 2008

This is a basic study of the remaining armors and helmets of the Joseon period for our better understanding and better maintenance of them. For the purpose, this paper shall try to show the present situations of the remaining armor and helmets of the period in Korea, and their typical classification for periodization, and the nomenclature about them. First, to oversee the present situations of the remaining armor and helmets of the period, study was done about the kinds of armors and helmets, their users, and their possessors today. It was found that the exact dates and users were unclear for many cases of the armors and helmets under our consideration. It is understandable when we consider many of them were exported to foreign countries, instead of being well-preserved in Korea upon excavations. Secondly, for their typical classifications for periodization, types were delineated from the pictures and drawings in reference to the periodical changes of them from Korean historical records. The result was that we can find out 4 types of armors, and 3 types of helmets, with their combinations. This shall be usefully applied for the better periodization of the remaining items. Thirdly, we come to the problem of naming of the remaining armors and helmets. For better nomenclature of the remains all the names of the armors and helmets for the Joseon period are collected from historical literature, to figure out some principles of nomenclature for them. I found some discrepancies with the present names of them, and my propositions are suggested to replace them.

• 디지털융복합연구
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• 제18권2호
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• pp.183-195
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• 2020

커뮤니케이션에서 중요한 비중을 차지하는 비언어적 요소들이 소셜미디어에 있어서도 그 활용성이 높아지고 있다. 본 연구에서는 페이스북 이용자들을 대상으로 Q 방법론을 통해 비언어적 요소들을 활용하는 주관적 인식 유형들을 찾아냈다. 우선 포커스 그룹 인터뷰를 시행하여 소셜미디어의 비언어적 요소들을 대표하는 34개의 Q 진술문들을 도출하였다. 페이스북 이용자들 19명을 대상으로 Q 소팅을 시행한 결과 비언어적 요소들을 서로 다르게 활용하는 3개의 그룹들을 대별할 수 있었다: 안전거리형, 은둔관조형, 전력투구형. 각각의 유형별로 현재 활용하는 비언어적 요소들과 미래에 필요할 것으로 보이는 비언어적 요소를 지원하기 위한 시스템의 기능들에 관해서 논의했다. 본 연구의 결과는 향후 온라인에서의 비언어적 요소나 기능들을 확장하기 위한 기초가 될 수 있을 것이다.

• 생태와환경
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• 제48권4호
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• pp.272-279
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• 2015

The aim of this study was to assess the interaction between Daphnia similis and various organisms related to the rice paddy ecosystem. We selected several organisms that are likely to prey on D. similis and evaluate predation rate as well as responses of D. similis to the chemical compounds exuded by these organisms. As a result of predation experiment, larval dragonfly (Anax parthenope) and Triops longicaudatus were clearly shown decreasing abundances of D. similis. Especially, Triops longicaudatus was observed higher feeding rates on D. similis than larval dragonfly. Chemical compounds from the vertebrates such as fish (Misgurnus anguillicaudatus, Pseudorasbora parva, Micropterus salmoides) and tadpole of frog (Rana nigromaculata) did not affect the life history of Daphnia. However, a potential predatory fish P. parva induced significantly longer tail spine in Daphnia. In addition, among the invertebrates (T. longicaudatus, A. Parthenope, Micronecta spp., Palaemon paucidens), chemical compounds exuded by T. longicaudatus induced shorter body and significantly longer tail spine in D. similis.