• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1173-1178
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• 2005

This paper proposes an IPMC actuating system with a bio-mimetic function. EMG signals generated by an intended contraction of muscles in forearm are used for the actuation of the IPMC. To obtain higher actuation force of the IPMC, the single layered as thick as 800 [${\mu}$m] or multi-layered IPMC (Nafion) of which each layer can be as thick as 178 [${\mu}$m] are prepared. The experimental results using an implemented IPMC control system show a possibility and a usability of the bio-mimetic artificial muscle.

• Journal of the Ergonomics Society of Korea
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• v.14 no.2
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• pp.1-14
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• 1995

Neuromuscular difference between normal subjects and low-back pain patients has been identified in terms of neural excitation signal measured by Electromyography (EMG) under the dynamic flexion/extension trunk motion. Ten healthy subjects and ten low-back pain patients were recruited for this study. New parameters and normalization technique were introduced to quantify the muscle excitation pattern among the flexor-extensor pairs of muscles : rectus abdominis (RA)-erector spinae (ES at L1 and L5 level), external oblique (EO)-internal oblique (IO), rectus femoris (quadricep : QUD)-biceps femoris( hamstring : HAM), and tibialis anterior (TA)-gastrocnemius (GAS). Results indicated that the temporal EMG pattern such as peak timing difference between the hip flexor (QUD) and extensor (HAM) and the duration of coexcitation between ES at L5 and RA muscle pairs showed a statistically significant difference between normal subjects and low-back pain patients. Improtantly, this study presented a new technique to identify the dynamic muscle excitation pattern that canb be least affected by EMG-length-velocity relationship. Further study can performed to validate this method for clinical application to quantitatively identify the low-back pain patients in the future.

• Journal of the Ergonomics Society of Korea
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• v.35 no.5
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• pp.439-447
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• 2016

Objective: The purpose of this study is to design a snow-removing tool using an ergonomic approach. Background: It is necessary to remove snow on the garden of a house or side street to prevent a fall hazard. When a user removes snow using a snow-removing tool, he or she experiences lots of physical discomfort. Therefore it is necessary to design a snow-removing tool to reduce a user's physical discomfort. Method: In this study, a new design for a snow-removing tool was developed considering user needs. The design prototype was compared with an existing tool through electromyography and subjective evaluation. Results: From the comparison evaluation, significant differences between the new design and the existing tool were identified in both muscle fatigue and subjective rating of discomfort. Conclusion: The result showed that the new design is better from the aspect of easing physical discomfort. Application: A new snow-removing tool can be developed using the design so that it can reduce a user's physical discomfort.

• Journal of the Ergonomics Society of Korea
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• v.29 no.4
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• pp.445-453
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• 2010

It is necessary to quantitatively evaluate the workload of workers in order to improve the level of safety and efficiency as well as to prevent workers from musculoskeletal disorders. The purpose of this study is to introduce biomechanical methods that are largely used to quantitatively evaluate workload. The biomechanical methods use kinematics and kinetics to analyze the movement and force of biomechanical body. Motion analysis, joint angle measurement, ground reaction force, mathematical model, and electromyography (EMG) were introduced as a tool or device for biomechanical evaluation. In this study, the special feature of each method was emphasized and important tips for field measurement were summarized. The information and technique disclosed in this summary can be used to evaluate and design the workplace better by effectively control the workload of field workers.

• Annals of Clinical Neurophysiology
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• v.7 no.2
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• pp.124-126
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• 2005

The effect of serratus anterior dysfunction is seen in the scapular winging. We report 2 cases with winging scapula clinically but do not reveal denervation potentials in needle electromyography. Surface myoelectric measurements of median frequency and root mean square values show difference in fatigability and amplitude in affected side.

• Journal of Biomedical Engineering Research
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• v.20 no.6
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• pp.601-607
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• 1999

상악(maxilla)과 하악(mandibular)의 최대 교합상태에서 하악을 기계적으로 자극(jaw jerk)할 경우 교근(masseter muscle)의 근전도 (electromyography)에서는 근신호가 일시적으로 침묵하는 형태의 휴지기(silent period) 현상이 발생한다. 턱관절 질환(temporo-mandibular joint dysfuntion)이 없는 정상인의 경우 24ms 정도의 휴지기가 나타나지만, 턱관절 질환 환자의 경우 평균 60ms 정도임을 볼 때 휴지기는 턱관절 질환을 진단하는 중요한 요소라 할 수있다. 본 논문에서는 이러한 휴지기 기간을 자동적으로 결정하기 위해 mCFAR 알고리즘을 제안하고 CLMS 적응 필터를 사용하여 근전도 신호의 왜곡을 가져오는 전원 잡음의 영향을 효과적으로 제거하였다. 실험 결과 전원 잡음에 대해 강건하며, 정확한 휴지기 기간을 결정할 수 있다.

• Journal of Korean Physical Therapy Science
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• v.21 no.1
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• pp.13-20
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• 2014

Purpose : The purpose of this study was to analyze and compare the surface electromyography(EMG) activity of trunk region muscle between normal subjects and chronic low back pain(CLBP) patients during one leg stance. Methods : The subjects were 27 people, were consisted of 12 subjects who don't have low back pain and 15 subjects who have low back pain from 19 to 28 year of age(mean age 22.22). We used surface EMG to evaluate the activity of the Rectus abdominis, External abdominal oblique, Quadratus lumborum, Gluteus medius muscle. We used independent two samples t-test for statistical data. Results : The result of this study showed that the maximal voluntary isometric contraction(%MVIC) ratio of the trunk muscles was higher in patients with CLBP than in normal subject. But there were no statistically significant differences. There were statistically significant differences of the activity of the Quadratus lumborum, Gluteus medius muscle(p<0.05).

• Journal of Biomedical Engineering Research
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• v.22 no.2
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• pp.211-216
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• 2001

본 연구에서는 상지의 동적 운동시, 상지의 주요 구동요소로서 주요 근육인 전박부 굴곡근, 신전근 및 이두박근 및 삼두박근의 근육들의 근전도를 측정하고, 이와 함께 동적 운동시의 주관절에 발생하는 관절모멘트, 근력, 근전도의 연관관계를 정량적으로 규명함으로써, 해당하는 근육의 근전도만의 측정으로 동적운동 시 필요한 근력의 정량적인 예상을 가능케 하는 수학적 모델을 제시하고자 하였다. 지금까지의 기존 연구는 근력의 등척성 수축운동에서의 근력 예측으로서, 실제 일상 생활에서 발생하는 인체내의 동적운동 상황에서의 근력을 산정 하는데 있어서 제한적 한계를 갖고 있었다. 따라서 본 연구는 실시간 동적 운동시 측정되는 근전도를 이용하여 해당하는 근육의 근력을 예측할 수 있는 수학적 모델을 제시하고자 하였다.

• Safety and Health at Work
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• v.6 no.1
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• pp.9-17
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• 2015

The human hand is a complex structure that performs various functions for activities of daily living and occupations. This paper presents a literature review on the methodologies used to evaluate hand functions from a biomechanics standpoint, including anthropometry, kinematics, kinetics, and electromyography (EMG). Anthropometry describes the dimensions and measurements of the hand. Kinematics includes hand movements and the range of motion of finger joints. Kinetics includes hand models for tendon and joint force analysis. EMG is used on hand muscles associated with hand functions and with signal-processing technology.

• Korean Journal of Applied Biomechanics
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• v.16 no.2
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• pp.55-63
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• 2006

The purpose of this study was to investigate the effects of vibration exercise using surface electromyography. Seven male collegiate wrestlers were participated in this study. Each subject stood on the platform and the vibration was induced for 1min. WEMG8 EMG system was used to record muscle activity from Vastus lateralis, Biceps Femoris, Tibialis Anterior, and Gastrocnemius. The EMG data were sampled for 30 sec. during non-vibration and vibration half squat position, respectively. The raw data were band pass filtered to remove noise and full wave rectified Paired sample t-test were performed to see the differences of maximum and average EMG between non-vibration and vibration trials. The results indicated that vibration produced much more muscle contraction than that of non-vibration trial for all selected muscles even though the significant difference was found only from Biceps Femoris. This phenomenon was due to the individual differences so care must be taken to evaluate vibration intensity and position before personal training.