• 대한물리치료과학회지
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• 제10권1호
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• pp.83-89
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• 2003

An electromyogram (EMG) using surface electrodes is one of the indirect tests most frequently used to ascertain muscle fatigue. An EMG can be used in two ways. The first technique determines the root mean square (RMS), which reflects the amplitude of the EMG signal. The second technique determines the median and mean power frequencies through EMG power spectrum analysis. The purpose of this article is for determine the correlation between work and percent root mean square(%RMS) and between work and MDF of EMG based on muscle contractions. It is used the %RMS, which reflects the amplitude of the EMG signal For MDF, it is used the frequency power spectrum analysis method, which involves the fast Fourier transformation (FFT) of the original Signals.

• 재활복지공학회논문지
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• 제7권2호
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• pp.69-74
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• 2013

본 연구에서는 손목 움직임의 추정을 위한 근전도 신호 기반 동작 분류 알고리즘을 제안한다. 근전도의 특징점을 추출하기 위하여 절대차분표준편차(DASDV)과 제곱평균제곱근(RMS)을 사용하며, 측정 된 근전도 신호를 이용하여 동작 마다 30개의 특징점(RMS, DASDV)을 추출한다. 근전도 신호를 특정한 패턴으로 나타내어 적용시키기 위하여 평균값을 기준으로 집단을 두 부분으로 나누고, 패턴분류 방법인 k-NN으로 패턴을 학습시킨 후, 집단을 나누지 않은 방법을 사용한 기존의 연구와 비교하여 제안한 알고리즘의 성능을 검증한다. 실험결과 제안한 알고리즘은 92.59%의 인식률을 보였으며, 이전 연구 결과보다 0.84% 포인트의 성능 개선을 보였다.

• 대한물리치료과학회지
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• 제19권4호
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• pp.1-6
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• 2012

Purpose : The current research examines the muscle activity that happens during scaling practice subject to 20 dental hygienic students with musculoskeletal pain and then propose a basic data according to the working attitude of the Dental Hygienist. Method : The Nordic-style questionnaire is used to define experimental group with musculoskeletal pain and control group. During the scaling the surface EMG device is used to measure the muscle activity of experimental and control group. Study design : The surface EMG is measure RMS(root mean square) of suboccipital muscle, biceps brachii, upper trapezius, and brachioradialis muscle activity. Results : In the experimental group, the RMS of upper trapezius and brachioradialis is increased during scaling practice(p<0.05), but the control group's RMS is not changed(p>0.05). Conclusion : Musculoskeletal pain may contribute to increase muscle activity of neck & arm during scaling practice. In the future we think there is a need to raise the office efficiency by subjecting to dental hyginiest that are in the clinics and performing experiments.

• 전기학회논문지
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• 제61권5호
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• pp.757-762
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• 2012

In this paper, the multi feature extraction algorithm for estimation of wrist movements based on Electromyogram(EMG) is proposed. For the extraction of precise features from the EMG signals, the difference absolute mean value(DAMV), the mean absolute value(MAV), the root mean square(RMS) and the difference absolute standard deviation value(DASDV) to consider amplitude characteristic of EMG signals are used. We figure out a more accurate feature-set by combination of two features out of these, because of multi feature extraction algorithm is more precise than single feature method. Also, for the motion classification based on EMG, the linear discriminant analysis(LDA), the quadratic discriminant analysis(QDA) and k-nearest neighbor(k-NN) are used. We implemented a test targeting twenty adult male to identify the accuracy of EMG pattern classification of wrist movements such as up, down, right, left and rest. As a result of our study, the LDA, QDA and k-NN classification method using feature-set with MAV and DASDV showed respectively 87.59%, 89.06%, 91.75% accuracy.

• The Journal of Korean Physical Therapy
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• 제20권1호
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• pp.11-16
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• 2008

Purpose: This study was undertaken to compare the signal characteristics of surface electromyography (EMG) between progressive resistive increase exercise (PRIE) and progressive resistive decrease exercise (PRDE). Methods: Forty healthy male subjects were randomly assigned to either the PRIE group or the PRDE group. Subjects participated in the PRIE and PRDE methods, with 10 RM for each subject. EMG activity was recorded from the rectus femoris muscle. Outcome data were collected for both groups pre-exercise, immediately post-exercise, then at 5 and 10 minutes post-exercise. Repeated measures 2-way ANOVA was used to determine the statistical difference of the root mean square (RMS) in EMG activity. Results: We showed that RMS values, when compared with pre-exercise, were decreased immediately after exercise and were increased at 5 and 10 minutes after exercise (p<0.05). The RMS values were not significantly different between the two groups (p>0.05). Conclusion: These results can indicate that both the PRIE and PRDE protocols will be improve strength with equivalent efficacy. Further studies are needed to address exercise duration, frequency of exercise sessions, and rest times than the PRIE and PRDE protocols with regard to the changes in strength improvement without a large amount of muscle fatigue.

• 대한의용생체공학회:의공학회지
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• 제21권2호
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• pp.219-224
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• 2000

본 연구는 몸통의 반복적인 flexion/extension 동작 수행시 근전도신호를 측정하고 이들 신호에서 나타난 EMG parameters(median frequency, median power, RMS) 와 피실험자의 주관적 불편도의 변화양상간의 정량적인 관계를 알아보고자 수행되었다. 피실험자별로 3-5회 정해진 업무를 수행하였고 주관적불편도와 근전도 신호를 측정하였다. 실험결과 반복횟수가 증가할수록 주관적 불편도는 증가하였으며 각 task 별로 EMG parameter와 불편도의 증감율 간의 회귀분석과 상관분석을 수행한 결과 실험과 EMG parameter에 따른 변이는 존재했지만 대체로 RMS에 비해 MF와 MP의 증감율이 불편도 증감율과 상관관계가 높은 것으로 나타났다.

• 한국운동역학회지
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• 제16권1호
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• pp.31-41
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• 2006

The primary purpose of a TKA is to restore normal knee function Therefore, ideally, a TKA should: (a) maintain the natural leverage of the knee joint muscles to ensure generating adequate knee muscle moments to accomplish daily tasks such as rising from climbing stairs; (b) provide adequate knee joint stability. A 16-channel MyoResearch XP EMG system was used to collect the differential input surface electromyography signals VM, VL, RF, BF, ST during climbing/descending stair tests. A Peak Motion Measurement System was used to collect the kinematic and kinetic data. AKIN-COM Ill isokinetic dynamometer was used for EMG of VM, VL, RF, BF and ST during maximal voluntary contraction. I Quadriceps EMG results for the VM of the passed 1year group limb demonstrated significant less RMS EMG than that of the passed 3year group limb $60^{\circ}-15^{\circ}$ of knee flexion(p<0.05). The VL of the passed 1year group limb also demonstrated significants less RMS EMG than that of the passed 3year group limb from $60^{\circ}-45^{\circ}$ of knee flexion(p<0.05). Similar to the VM and VL, the RF of the passed 1year group limb showed less RMS EMG than that of the passed 3year group limb from $60^{\circ}-30^{\circ}$ do knee flexion(p<0.05). Hamstring EMG results for the BF of the passed 1year group limb demonstrated less RMS EMG than that of the passed 3year group limb from $75^{\circ}-15^{\circ}$ of knee flexion(p<0.05). The passed 1year group limb tended to have less ADD displacement(p<0.071) than that of the passed 3year group limb. There was no significant difference of the ABD displacement between the passed 1year group and the passed 3year group limbs(p<0.73). The passed 3year group used compensatory adaptation movement strategies to compensate for the strength deficit of passed 3year group limbs. The passed 3year group limb also increased the quadriceps muscle activation level to produce more knee extension moment to compensate for the short quadriceps moment arm. The passe 3year group limb might have an unstable knee joint in the medio-Iateral direction during the climbing/descending by showing a tendency of more ADD displacement and greater hamming co-activation EMG than the passed 1year group limbs. The TKA design was not able to help the knee joint to produce adequate knee extension moment with less quadriceps muscle effort. I think that old man needs continuous exercise for muscle strength.

• 한국전문물리치료학회지
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• 제10권1호
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• pp.37-50
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• 2003

The purpose of this study was to compare visual analogue scale (VAS), pain threshold (PT), $%RMS_{RVC}$, and EMG gaps before and after applying transcutaneous electrical nerve stimulation (TENS) on the upper trapezius muscle at the patients with myofascial pain syndrome (MPS). The subjects were 4 men and 10 women composed of both the inpatients and outpatients who were diagnosed as MPS at Wonju Medical Center. VAS and PT measurements were performed to assess the subjective pain level. The reference voluntary contraction (RVC) test was performed for 15 seconds for normalization on the bilateral trapezius muscle using surface electromyography (sEMG). After 3-minute resting time, the EMG signal was recorded while performing a typing activity for 2 minutes and then TENS was applicated with a comfortable intensity for 10 minutes. The EMG activity of the upper trapezius muscle was recorded during typing for 2 minutes. The results of study were as follows: 1) VAS score was significantly decreased on the more painful side after treatment, however, it was not significantly different on the less painful side. 2) PT was increased after treatment on both sides, however, it was not significantly different between before and after the TENS application. 3) The EMG activity during typing was significantly decreased after treatment, and 4) The EMG gaps were significantly increased after TENS treatment compared to before it. Consequently, the study showed that TENS was effective in decreasing VAS, $%RMS_{RVC}$, and in increasing EMG gaps. The EMG gap analysis could be a useful method to measure pain in patients with MPS in the upper trapezius.

• 한국정보전자통신기술학회논문지
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• 제12권4호
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• pp.413-418
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• 2019

뇌와 관련된 질병(치매, 조현병, 우울증, 파킨슨병 등)을 가진 환자의 치료 및 재활 정도의 진행을 확인하고자 하는 연구가 현재 활발히 진행되고 있는 추세이다. 그 중에서 경두개 자기 자극법(Transcranial magnetic stimulation, TMS)은 뇌 질환이 있는 환자에게 비 침습적으로 뇌 신경 조절에 사용되는 기법이기 때문에 치료에 많이 사용되고 있다. 경두개 자기 자극 시 정상인의 근피로도는 증가하는 경향을 확인할 수 있다. 따라서 본 논문에서는 경두개 자기 자극 시에 운동 신경 유발 응답 측정을 위한 근전도 측정 시스템을 구축하여 피실험자의 Raw Data를 RMS 기법으로 분석하고, RMS 그래프의 경향을 통해 운동 신경 유발 응답 측정 시스템을 확인하고자 하는 것이 목표이다. 실험 방법으로는 피실험자의 위팔두갈래근의 수축과 이완 운동을 통해 피로한 상황까지 도달하게 한 후, 표면 근전도 기기를 통해 받아들인 원신호를 RMS 기법으로 분석한다. 실험 결과, RMS 그래프가 상승하는 경향을 확인 하였고, 이를 통해 구축된 근전도 측정 시스템으로 운동 신경 유발 응답을 측정한 데이터를 고려하여 개개인에 맞는 자기자극 강도 결정에 활용될 수 있을 것으로 사료된다.

• 한국전문물리치료학회지
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• 제13권2호
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• pp.61-69
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• 2006

The purpose of this study was to compare the electromyography (EMG) activities of the lumbar extensor muscles during motion of trunk flexion-extension and compare range of motion (ROM) with a 3-dimensional motion analysis system of the lumbar region between subjects with chronic low back pain (CLBP) and healthy subjects during the trunk flexion-extension, trunk rotation and trunk lateral flexion cycle. Thirty CLBP subjects and thirty healthy subjects were included. We measured the root mean square (RMS) value of the lumbar extensor muscles from resting, standing, lumbar flexion and return position. The RMS ratio was normalized from maximal EMG activity of the lumbar extensor muscles during trunk motion. The results of this study showed that the RMS ratio of the lumbar extensor was significantly higher in CLBP subjects than healthy subjects during all of trunk motion (p<.05). The ratio of the highest RMS value during flexion and extension was higher in CLBP subjects than in healthy subjects (p<.05). The ROM of the lumbar region was significantly lower in CLBP subjects than healthy subjects during trunk flexion-extension, trunk rotation and lateral flexion cycle. The relationship between the RMS ratio for full lumbar flexion and the ROM of lumbar flexion was not correlated significantly. CLBP subjects have both decreased ROM of the lumbar region and higher muscle activities of the lumbar extensor muscle than healthy subjects.