• 대한기계학회논문집A
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• 제34권10호
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• pp.1345-1350
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• 2010

앉기-서기 동작은 인간의 생체역학적 기능 정도를 결정할 수 있는 기본적인 일상생활 동작의 하나이다. 동작 중 발생하는 관절의 운동 정보와 모멘트, 그리고 근력을 예측하는 것은 앉기-서기 동작의 특성을 이해하는데 필요하다. 본 연구에서는 동작 기반 역동역학해석 프로그램과 근전도 기반 근력예측 프로그램을 개발하였다. 개발된 프로그램과 앉기-서기 동작 실험에서 측정한 동작, 지면반력, 그리고 근전도신호 정보를 이용하여 실험적 방법으로 측정하기 힘든 관절각도, 관절모멘트, 및 근력을 예측하고 기존 연구결과와 비교하여 검증하였다. 개발된 기법과 프로그램들은 일상생활 동작에서의 관절 생체역학과 근육 협응에 대한 지식을 얻는 데 사용될 수 있으리라 기대한다.

• 융합정보논문지
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• 제10권4호
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• pp.160-167
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• 2020

본 연구는 달리기 시 속도와 경사변화가 하지관절의 생체역학적 요인에 미치는 영향을 보고자 한다. 이를 위해 20대 성인남성 15명이 트레드밀에서 2.7, 3.3 m/s와 -9°, -6°, 0°, 6°, 9°로 달리기를 실시하였고, 속도와 경사 변화에 따른 주행특성(보장, 보빈도), 생체역학적 변인(발목, 무릎, 엉덩관절의 가동범위, 모멘트, 관절파워), 지면반력(수직지면반력, 부하율, 제동력, 추진력)을 측정하였다. 연구결과, 주행특성은 오르막 달리기(UR)가 내리막 달리기(DR)에 비해 크게 나타났다(p<.05). 하지관절의 가동범위와 수직지면반력은 UR에서 크게 나타났고(p<.05), 하지관절의 모멘트와 제동력, 추진력, 부하율은 DR에서 크게 나타났다(p<.05). 관절파워는 발목관절은 DR에서 크고, 엉덩관절에서는 UR이 크게 나타났다(p<.05). 이러한 결과로부터 3.3m/s의 속도로 DR을 달리는 경우에서 발목관절 부상의 영향이 클 것으로 예상된다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.959-964
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• 1992

This study treats the method for kinematic modeling of the biped walking robot, for synthesizing various gait trajectories, and for calculating adequate values of the joint torque inside the stable region. To synthesize various and anthropomorphic walking easily, the gait trajectory is specified by a set of ten walking prameters, and the trunk motion equation is derived by the zero moment point and the gait trajectory. By distributing ground reaction force and moment reduced at the zero moment point to the both feet, the joint torque equation can be derived readily, and according to this equation, the joint torque to stable walking can be computed.

• 대한기계학회논문집
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• 제17권1호
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• pp.223-235
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• 1993

본 연구에서는 첫째로 병진 캠 전용해석 및 설계 프로그램을 개발하였다. 이 개발된 프로그램들을 기구해석전용 프로그램에 접속시켜 VTR Deck에 대한 전반적인 해석 및 설계가 가능하도록 하였다.

• 한국운동역학회지
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• 제24권1호
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• pp.59-66
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• 2014

The purpose of this study was to investigate the effects of knee joint muscle fatigue and overweight on shock absorption during single-leg landing of adult women. Written informed consent forms, which were approved by the human subject research and review committee at Dong-A University, were provided to all subjects. The subjects who participated in this study were divided into 2 groups: a normal weight group and an overweight group, consisting of 15 young women each. Both the normal weight group and the overweight group showed that use soft landing and ankle dominant strategy. The peak vertical ground reaction force, the knee joint absorption power, and eccentric work done, as the increase of knee joint muscle fatigue level, showed a decrease. And the hip joint absorption power and eccentric work done, as the increase of weight, was less than the overweight group showed the normal weight group. In conclusion, the accumulation of the knee joint muscle fatigue and the increase of body weight may lead to an increased risk of injury during landing.

• 한국운동역학회지
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• 제17권2호
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• pp.75-82
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• 2007

The purpose of this study was to analyze and compare the effect of gait time on the gait patterns in elderly female OA and non-OA patients. The intensity of the subjects joint pain was surveyed by using WOMAC. Twelve subjects participated in this study. Measurements were taken for every the 10 minutes for 30 minutes after walking by a force plate. The following variables were recorded; double stance support time, Fx, Fy, Fx_time, Fz and so on. From the investigation of these variables the following was observed and concluded. The Fz values for the OA group was 1.01BW at the start and after 30 minutes was 1.04BW on the other hand the non-OA group's Fz1 was 1.08BW and 1.10BW. There was no significant difference calculated between the two groups and at the start and end of the experiment about all the variables. Therefore, it is concluded that there was no negative effect caused by walking for the 30 minutes and that it was an effective way of strengthen both respiratory and muscle function.

• 한국정밀공학회지
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• 제32권4호
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• pp.377-386
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• 2015

Joint force/torque estimation by inverse dynamics is a traditional tool in biomechanical studies. Conventionally for this, kinematic data of human body is obtained by motion capture cameras, of which the bulkiness and occlusion problem make it hard to capture a broad range of movement. As an alternative, inertial motion sensing using cheap and small inertial sensors has been studied recently. In this research, the performance of inertial motion sensing especially to calculate inverse dynamics is studied. Kinematic data from inertial motion sensors is used to calculate ground reaction force (GRF), which is compared to the force plate readings (ground truth) and additionally to the estimation result from optical method. The GRF estimation result showed high correlation and low normalized RMSE(R=0.93, normalized RMSE<0.02 of body weight), which performed even better than conventional optical method. This result guarantees enough accuracy of inertial motion sensing to be used in inverse dynamics analysis.

• International Journal of Internet, Broadcasting and Communication
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• 제13권1호
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• pp.47-53
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• 2021

Gait kinematics and kinetics have a similar tendency between men and women, yet it remains unclear how walking while carrying a load affects the gait mechanism. Twenty adults walked with preferred velocity on level ground of 20 m relative to change of a load carriage (no load, 15%, 30% of the body weights) aimed to observe gait mechanism. We measured gait posture using the three-dimensional image analysis and ground reaction force system during stance phase on left foot. In main effect of gender difference, men showed increased displacement of center of gravity (COG) compared to women, and it showed more extended joint angle of hip and knee in sagittal plane. In main effect of a load difference, knee joint showed more flexed postuel relative to increase of load carriage. In main effect of load difference on the kinetic variables, medial-lateral force, anterior-posterior force (1st breaking, 2nd propulsive), vertical force, center of pressure (COP) area, leg stiffness, and whole body stiffness showed more increased values relative to increase of load carriage. Also, men showed more increased COP area compared to women. Interaction showed in the 1st anterior-posterior force, and as a result of one-way variance analysis, it was found that a load main effect had a greater influence on the increase in the magnitude of the braking force than the gender. The data in this study explains that women require little kinematic alteration compared to men, while men in more stiff posture accommodate an added load compared to women during gait. Additionally, it suggests that dynamic stability is maintained by adopting different gait strategies relative to gender and load difference.

• 한국임상수의학회지
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• 제20권4호
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• pp.504-507
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• 2003

Force plate analysis was used to describe the effect of acupuncture on right knee osteoarthritis (OA) in a seven-year-old hound breed dog weighing 27 kg. The acupuncture treatment was performed twice a week for 3 weeks. Ground reaction forces (GRFs) and subjective clinical scores in both hind limbs were obtained prior to and 72 hours after each treatment. Right vertical peak force was increased as the dog was acupunctured. Although their sensitivity was lower than that of the GRF data, the subjective clinical scores reflected an improvement. In addition, vertical peak force of normal left hind limb was also increased during this trial. These results indicate that gait analysis may be valuable objective method in future evaluation of acupuncture for OA of the stifle joint.

• 한국초전도ㆍ저온공학회논문지
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• 제9권1호
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• pp.76-81
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• 2007

This paper deals with the characteristics of a small scale $high-T_c$ superconducting(HTSC) levitation system. The levitation tester. which models after electrodynamic suspension(EDS) maglev, consists of one HTSC magnet, a reaction plate, and force measuring components. Instead of moving magnet, AC current was applied to the fixed HTSC magnet. The magnet also has persistent current switch(PCS). The inductance of the magnet was 18.5 mH and total joint resistance of the magnet was $5.74{\times}10^{-7}\Omega$. AC current was applied into the HTSC magnet with various frequencies and the levitation force was calculated and measured. According to the increase of the vehicle speed, the levitation force was saturated.