• 대한정형도수물리치료학회지
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• 제16권2호
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• pp.67-75
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• 2010

Purpose: The purpose of this is to identify the relationship among the age, body mass index(BMI) and exercise frequency(EF) with knee joint position sense in korean healthy women. Methods: Healthy women of 328 who participated in this study were tested knee joint position sense; reposition error was measured with a Myrin goniometer. Each reposition error was analyzed using descriptive statics, pearson correlation coefficients, and stepwise multiple regression. Results: The mean reposition error by age groups was significant decrease getting older. The mean reposition error by BMI groups was significant decrease getting higher. And the mean reposition error by EF groups was significant decrease getting lower. The knee joint position sense showed a significantly correlation with age(r=0.36, p=.00), BMI(r=0.34, p=.00) and EF(r=-0.50, p=.00). The most powerful predictor of knee joint position sense was EF. The reposition error according to stepwise multiple regression is $3.36+(-2.64){\times}EF+0.13{\times}age$, and account for 46%($R^2=0.46$) of the variance in the knee joint position sense. Conclusion: The older the women are, for prevent of knee injuries due to decreased joint position sense, regular exercise is essential factor.

• 한국전문물리치료학회지
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• 제14권3호
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• pp.90-96
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• 2007

The purpose of this study was to compare the joint position sense at the knee joint at 3 different surface conditions by using the active knee joint angle reproduction test in the standing position. Twenty healthy volunteers (10 males and 10 females) age 20~29 years were recruited for this study. The knee joint position senses were assessed at three different surface conditions: on the floor (stable condition), TOGU (soft condition), and seat fit (unstable condition) in a closed kinetic chain. Testing orders were selected randomly. The absolute angle error was defined as the absolute difference between target angles ($30^{\circ}{\sim}45^{\circ}$ knee flexion) and subject perceived angle of the knee flexion. One way ANOVA was used to compare the absolute angle of error among 3 different conditions. The Independent t-test was used to compare the absolute angle of error between male and female. The error angles were significantly different among surface conditions ($1.3^{\circ}{\pm}1.2^{\circ}$ for the floor, $2.1^{\circ}{\pm}0.9^{\circ}$ for the TOGU, and $4.4^{\circ}{\pm}1.8^{\circ}$ for the seat fit, p<.05). There was no significant difference in error angle between male and female. In conclusion, the joint position sense of the knee joint in the closed kinetic chain decreased at unstable surface conditions. The result of this study indicates that surface conditions should be considered when assessing and training the joint position sense of the knee joint in clinical setting.

• PNF and Movement
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• 제8권1호
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• pp.31-39
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• 2010

Purpose : The purpose of this study is to ascertain whether age, body mass index(BMI) and exercise frequency(EF) are correlated with knee joint position sense in healthy women. Methods : Healthy women of 150 who participated in this study were tested knee joint position sense; each reposition error was analyzed according to the age, BMI and EF. Reposition error was measured with a Myrin goniometer. Results : The age groups, BMI groups and EF groups demonstrated significant differences of the knee joint position sense. The older the healthy women are, the higher BMI is, and the lower EF is, the more decreased knee joint position sense has become. Conclusion : The older the women are, the higher BMI is, and the lower EF is, the more decreased the knee joint position sense in healthy women is. Therefore it needs to be considered to require management of obesity and regular exercise for prevention of knee injuries due to decreased joint position sense.

• 한국전문물리치료학회지
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• 제10권3호
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• pp.63-70
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• 2003

The purpose of this study was to compare the difference of joint position sense between measurements. Fourteen healthy male subjects were recruited for this study. The elbow joint position senses were measured using angle reproduction test. The elbow joint position sense was assessed with three experimental conditions: ipsilateral reproduction test in open-chain condition, contralateral reproduction test in open-chain condition, ipsilateral reproduction test with weight in open-chain condition and ipsilateral reproduction test in closed-chain condition. The angular difference between stimulus position and the reproduced position (angular error) was calculated in all testing conditions to examine the accuracy of the joint position sense. One way ANOVA was used to compare the error angles in all experimental conditions. The error angles between measurements were significantly different in elbow joint. The error angles was smallest in ipsilateral reproduction test with weight in open-chain condition and was greatest in the contralateral reproduction test in open-chain condition. Findings of this study indicate that testing methods, types of task, existence of resistance should be considered in clinical assessment for the joint position sense.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 춘계학술대회 논문집
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• pp.672-675
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• 2000

There are many sources of errors in the parallel device. This study investigates the effect of a clearance error at a U-joint on the position and orientation errors of the platform of a new parallel device, cubic parallel manipulator. In this study, the limits of errors can be estimated for given conditions.

• 대한정형도수물리치료학회지
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• 제28권1호
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• pp.39-51
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• 2022

Background: The purpose of this study is to investigate the effect of neck and shoulder self-stretching exercise using audiovisual media on neck pain, postural alignment, and joint position error in women with chronic neck pain. Methods: The subjects included 20 women that gave consent to participate in the study voluntarily. They performed the self-stretching exercises using audiovisual media was carried out 20 minutes 5 times a week during 3 weeks. Neck disability index (NDI) and visual analogue scale (VAS) were used to measure the functional disability and pain, A pressure pain threshold was measured using an algometer, and a cervical range of motion (CROM) measurement tool was used to measure the range of motion and error of proprioceptive position sense of the cervical spine. To assess posture alignment, forward head angle (FHA), forward shoulder angle (FSA) were measured using image J software. Results: The neck pain intensity was statistically significantly within group (p<.05). Neck and shoulder functional disability were a statistically significant difference within group (p<.05). Splenius capitis and upper trapezius pressure pain threshold were statistically significant difference in within group (p<.05). The postural alignment was statistically significantly within group (p<.05). The cervical range of motion in neck extension, right and left lateral flexion were statistically significantly within group (p<.05). The joint position error in neck flexion, extension, right and left lateral flexion decreased statistically significantly within group (p<.05). Conclusion: Self-stretching exercise using audiovisual media increased the mobility of the neck, decreased neck pain and joint position error, and improved posture alignment. As a result, there was a positive effect by applying the self-stretching exercise using audiovisual media to people with neck pain. Based on this, it is thought that it can be used as the basis for research related to home training programs for healthy self-management.

• 대한물리치료과학회지
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• 제3권3호
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• pp.15-23
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• 1996

The purpose of this study to evaluate and compare the proprioception of the dominant knee joint at different conditions in normal 20 years of age. The pripriocption was measured at sitting, supine, prone position with the eyes opened and the eyes closed. All were assessed with and without a knee brace around the knee by reproduction the position to which a joint has previously been placed. In this study, 24 rehabilitation therapy major students were assessed at Hansoe University. In this study applied the paired t-test and 1-way ANOVA to determine the statistical significance of results at 0.05 level of significance. The error average of proprioception was $4.65{\pm}2.95^{\circ}$ with the eyes closed and $4.08{\pm}1.14^{\circ}$ with the eyes opened in sitting position, $5.56{\pm}3.18^{\circ}$ with the eyes closed and $4.98{\pm}2.99^{\circ}$ with the eyes opened in supine position and $5.60{\pm}1.64^{\circ}$ with the eyes closed and $4.87{\pm}2.16^{\circ}$ with the eyes opened in prone position. There was no significantly difference the error average between the eyes opened group and the eyes closed group. There was no significantly difference the error average among the three positions. The error average decreased significantly in knee brace group at all conditions.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.789-794
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• 2000

This study proposes an error analysis for a cubic parallel device. There are many sources of errors in the device. An error analysis is presented based on an error model formed from the relation between the universal joint error of the cubic parallel manipulator and the end effector accuracy. The analysis shows that the method can be used in evaluating the accuracy of a parallel device.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.1-6
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• 1992

A principle of "orthogonalization" is proposed as an extended notion of hybrid (force and position) control for robot manipulators under geometric endpoint constraints. The principle realizes the hybrid control in a strict sense by letting position and velocity feedback signals be orthogonal in joint space to the contact force vector whose components are exerted at corresponding joints. This orthogonalization is executed via a projection matrix computed in real-time from a gradient of the equation of the surface in joint coordinates and hence both projected position and velocity feedback signals become perpendicular to the force vector that is normal to the surface at the contact point in joint space. To show the important role of the principle in control of robot manipulators, three basic problems are analyzed, the first is a hybrid trajectory tracking problem by means of a "modified hybrid computed torque method", the second is a model-based adaptive control problem for robot manipulators under geometric endpoint constraints, and the third is an iterative learning control problem. It is shown that the passivity of residual error dynamics of robots follows from the orthogonalization principle and it plays a crucial role in convergence properties of both positional and force error signals.force error signals.

• 전자공학회논문지SC
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• 제41권3호
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• pp.17-24
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• 2004

동일한 작업을 반복하여 수행하는 불확실한 로봇 시스템을 위한 P형 반복 학습 제어기를 제안한다. 제안된 반복 학습 제어기는 조인트 위치 오차로 구성되는 선형 피드백 제어기와 현재의 조인트 속도 오차로 갱신되는 피드포워드 및 피드백 학습 제어기로 구성된다. 반복 작업 동작이 계속 진행됨에 따라 조인트 위치와 속도 오차는 균일하게 0으로 수렴한다. 반복 횟수에 따라 변화하는 학습 이득을 채택함으로서 반복 횟수 영역에서 임의적으로 수렴 비율을 조절할 수 있는 조인트 위치, 속도 오차한계를 제시하고, 조인트 위치와 속도 오차는 그 한계 내에서 반복 횟수 영역에서 0으로 수렴한다. 기존의 P형 반복 학습 제어기와는 달리 제안된 반복 학습 제어 알고리즘은 학습 이득을 적절하게 설계함으로써 반복 횟수 영역에서 오차 수렴 비율의 분석과 조정을 가능하게 하는 장점이 있다.