Jaebum Park

EWOD (electrowetting on dielectric) is a viable scheme to drive optofluidic devices that utilize the liquid interface as a refractive surface. Although AC (alternating current) voltage is often applied to an electrode in EWOD devices to improve electrical characteristics, it may cause oscillations of liquid interfaces which can be detrimental to the system's performance as an optical device. Here we experimentally identify the origin of the interfacial oscillations of polymeric electrolyte solut

Objective: To investigate the effect of short-term vibration frequencies on muscle force generation capabilities. Method: Six healthy participants were recruited for this study and only their dominant leg was tested. The subjects were tested under five conditions of vibration frequencies with constant amplitude: 0 Hz (no vibration), 30 Hz, 60 Hz, and 90 Hz, and the vibration amplitude was 10 mm for all frequency conditions. The vibration was applied to the rectus femoris (RF). The subjects were

Objective: The purpose of this study was to examine the effect of changes in degrees of freedom of the fingers (i.e., the number of the fingers involved in tasks) on the task performance during force production and releasing task. Method: Eight right-handed young men (age: 29.63±3.02 yr, height: 1.73±0.04 m, weight: 70.25±9.05 kg) participated in this study. The subjects were required to press the transducers with three combinations of fingers, including the index-middle (IM), index-middle-ring

Objective: The purpose of this study was to examine the effect of degrees of freedom on the multi-synergies in two hierarchies of human hand system during force production and releasing tasks. Method: In this study, the constrained movements of the aiming and releasing actions using both hands and fingers during archery-like shooting were implemented as experimental tasks. The participants produced a pulling force holding the customized frame (mimicking an archery bow, with a set of force transd

청소년의 건강과 체력을 다면적으로 정량화하여 적합한 체육교육과 연계하기 위한 노력은 중등교육에 있어서 필수적인 요소이다. 본 연구에서는 최근 운영이 확대되고 있는 학생건강체력 평가제(PAPS)가 본래의 취지에 부합하여 다양한 건강체력의 요소들을 독립적으로 평가하고 있는지 검토하였다. PAPS를 통해 총 798명(남:399, 여:399) 고등학교 학생들의 건강체력 및 체질량 지수(BMI)를 남녀 그리고 학년별로 분석하여 건강체력 요소들 간의 관계를 조사하였으며 특히 기존 체력장과 비교하여 PAPS에서 새로이 추가된 BMI와 건강체력 요소의 상관관계를 분석하였다. 그 결과 남학생의 경우는 심폐지구력과 순발력이 독립적으로 평가되고 있는 지에 대한 재고가 필요한 것으로 판단된다. 또한 정상보다 높은 BMI 수치가 운동능력에 부정적 영향을 미치는 경향은 여학생에 한해서만 관찰되었으며 이는 남학생의 비만도가 여학생에 비하여 상대적으로 과대평가되었을 가능성을 시사한다. PAPS가 정확한 신체조성

무용수가 정확하고 아름다운 움직임을 만들어 내기 위해서는 당사자는 물론 교수자의 역할이 중요하다. 무용 교사들은 무용수의 기술적, 예술적 결점을 해결하는데 도움이 되는 적절한 지식을 전달해야 한다. 간결하고 정확한 동작을 구사하기 위해서는 신체와 움직임에 대한 기본적인 이해가 필요하다. 잘 훈련된 무용수의 정량적 움직임 을 파악하는 것은 실기 훈련 시 객관적인 지표의 역할을 할 수 있다. 따라서 본 연구에서는 프로 발레 무용수와 아마추어 무용수의 아라베스크 수행 시의 운동학적 차이를 정량적으로 밝히는데 목적이 있다. 10명의 여성 프로 발레 무용수와 10명의 여성 아마추어 무용수가 참여하였다. 모든 연구 참여자는 파세- 아라베스크 동작을 10회 반복 수행하였다. 모든 수행의 분석은 동작 분석 시스템을 통해 실시되었다. 아라베스크 동작 수행 능력 검증을 위해 전신 신체 질량 중심, 다리의 높이 및 위치, 그리고 움직임 다리의 수행 전략 검증을 위해 다리의 각 변위, 다리의 최대 각 속

Objective: This study examined the effects of stimulating fingertip temperature on the patterns of force sharing and stability properties during multi-finger force production tasks. Method: 9 adult subjects (male: 3, female: 6, age: 26.11±4.01 yrs, height: 169.22±5.97 cm, weight: 61.44±11.27 kg) participated in this study. The experiment consisted of three blocks: 1) maximal voluntary contraction (MVC) task, 2) single-finger ramp task to quantify enslaving (i.e., unintended force production by n

PURPOSE: To investigate the effect of muscle vibration on performance accuracy and multi-muscle coordination pattern during voluntary isometric knee extension torque production. METHODS: The subjects were tested under two conditions of external vibration frequencies (90 Hz vibration (VIB)&no-vibration (NVIB)) with three levels of torque magnitudes of 20% (MVT20), 40% (MVT40), and 60% of maximal voluntary torque (MVT60). The subjects were instructed to perform a submaximal isometric ramp task and

Objective: The purpose of this study is to identify the mechanism of changes in maximum voluntary torque with the magnitude and duration of pre-activation torque during voluntary isometric knee extension. Method: 11 male subjects (age: 25.91±2.43 yrs., height: 173.12±3.51 cm, weight: 76.45±7.74 kg) participated in this study. The subjects were required to produce maximal voluntary isometric torque with a particular pre-activation torque condition. The properties of pre-activation torque consiste

PURPOSE: This study examined the issue of history-dependence on muscle excitation and oxygenation by using surface electromyography (EMG) and near-infrared spectroscopy (NIRS). METHODS: Eight male participants performed isometric knee extension force production tasks that started at four levels of initial force production (30, 40, 60, 70% of maximal voluntary contraction, MVC) and commonly converged to the production of 50% of MVC by increasing or decreasing knee extension forces. We quantified

This study aimed to introduce the characteristics of adults with developmental coordination disorder (DCD) and to provide basic information on assessment tools for screening adults with DCD. Firstly, we analyzed 25 domestic articles published from 2000 to 2022 selected based on predefined analysis criteria. It was confirmed that there was currently no domestic peer-reviewed journal article on adults with DCD in Korea, and one ongoing research on adults with DCD was funded by the National Researc

PURPOSE: This study examined the effect of anticipatory control strategies on stable upright posture and consistency in archery performance among skilled elite archers. METHODS: Nine skilled archery players participated in this study and performed repeated shooting trials under two different shooting conditions: clicker and non-clicker. In the clicker condition, archers shot in response to clicker signals, whereas in the non-clicker condition, they used an anticipatory strategy to determine shoo

The purpose of this study is to explore the feasibility and therapeutic potential of creative dance (CD) based exercise as a rehabilitation intervention for adolescents with cerebral palsy (CP). Participants were 10 adolescents with spastic CP (mean age, 17.5± 2.12 years; Gross Motor Function Classification System levels I [n= 3] and II [n= 7]). Outcome measures included the Gross Motor Function Measure-88 (GMFM-88; dimensions D and E), spatiotemporal gait parameters, lower limb range of motion

This study compared differences in pitching kinematics between normal-weight and overweight high school baseball pitchers. Twenty male pitchers were included in the study. According to the 2020 guidelines on the Body Mass Index (BMI) standard for children and adolescents by the Korean Society for the Study of Obesity, 10 participants with BMI below the 85% percentile were assigned to the normal-weight group, and 10 participants with BMI above the 85% percentile were assigned to the overweight gr