• Journal of Biomedical Engineering Research
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• v.13 no.1
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• pp.9-18
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• 1992

This paper describes a quantitative analysis of electromyography (EMG) measured from seven subjects performing four seated dynamic tasks. EMG signals were mom- bored using 15 surface electrodes which were placed on selected trunk and lower extrmity muscles of the right side of the body. Each EMG signal was then processed through rectification, integration, and filtering. Based on the maximum level of the processed EMG, it was found that the trunk and ankle muscles play an important role on the postural control during the seated tasks.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.699-701
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• 1987

This paper deals With the EMG signal processing to apply the EMG signal to the Prosthetic arm. The EMG signals are generated by the voluntary contractions of the subject's musculature and is coded into binary words by the pulse width modulation. Command strings or sentences are constructed by concatenating several words, and are syntactically described by a context free grammar in Chomsky normal form and is tried to classify the movement pattern by the CYK algorithm.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.815-816
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• 2006

In this paper, an EMG (Electromyography) sensor for utilizing an EMGl-based HCI are described. The EMG sensor is a dry type and has high gain (1000-10000). Therefore, this sensor can be properly applied to HCI devices using EMG signals without additional amplification circuit.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.84.4-84
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• 2001

In this paper, we present a method to classify electromyogram (EMG) signals which are utilized to be control signals for patient-responsive walker-supported system for paraplegics. Patterns of EMG signals for dierent walking motions are classied via adequate filtering, real EMG signal extraction, AR-modeling, and modified self-organizing feature map (MSOFM). More efficient signal processing is done via a data-reducing extraction algorithm. Moreover, MSOFM classifies and determines the classified results are presented for validation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4629-4635
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• 2012

This study was aimed at the relationship between peak EMG amplitude on low back muscles acting on L5/S1 and load center of gravity, trunk lateral bending while lifting an object. Musculoskeletal disorders including low back pain can occur even when handling heavy objects only once as well as when doing non-heavy materials repeatedly. 11 male subjects with average 23 age were required to lift a 15.8kg object symmetrically three times. Peak EMG amplitudes on 6 muscles related with L5/S1 were recorded and analyzed. The lifting conditions consisted of lifting symmetric load with no trunk lateral bending, asymmetric load with no trunk lateral bending, and asymmetric load with trunk lateral bending to the load center of gravity within an object. The results showed that peak EMG amplitude on back muscles contralateral to load center of gravity was observed greater in comparison with the symmetric load. Also, in case of lifting asymmetric load the posture with trunk lateral bending increased peak EMG amplitude on muscles contralateral to load center of gravity more than with no trunk lateral bending. This research can be used as one administrative intervention in order to reduce the low back pain incidence with suggesting workers that they keep the trunk not bending to load center of gravity if possible when lifting a heavy asymmetric object.

• Journal of Biomedical Engineering Research
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• v.25 no.2
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• pp.151-156
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• 2004

The purpose of this study was to develop EMG triggered FES system for restoration of upper extremity function in chronic hemiplegic patients and to identify the optimal location of electrode application for the EMG triggered FES system which produces effective muscle contraction and detects EMG activity for extension in the wrist and finger joints. The stimulus system was composed of EMG measuring component, constant current component and the program for muscle contraction by EMG triggered FES and passive FES. Parameter of electrical stimulation was 35 ㎐ in frequency, 150 ${\mu}\textrm{s}$ in pulse width and symmetric bi-phasic wave. In 15 hemiplegic patients, EMG triggered FES was applied to the proximal half of forearm which was divided into 12 areas. The most sensitive area for measuring EMG activities during extension of the wrist and fingers was area 4, 5 and the optimal location of electrical stimulation for producing extension of the wrist and fingers was area 4, 5, 7, 8. These results suggest that the area 4 and 5 was considered as the most optimal location of electrode application for measuring EMG activities as well as producing extension of the wrist and fingers by EMG triggered FES system.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.1
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• pp.119-128
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• 2017

G-induced Loss of Consciousness(G-LOC) can be predicted by measuring Electromyogram(EMG) signals. Existing studies have mainly focused on specific body parts and lacked of consideration with quantitative EMG indices. The purpose of this study is to analyze the indices of EMG signals by human body parts for monitoring G-LOC condition. The data of seven EMG features such as Root Mean Square(RMS), Integrated Absolute Value(IAV), and Mean Absolute Value(MAV) for reflecting muscle contraction and Slope Sign Changes(SSC), Waveform Length (WL), Zero Crossing(ZC), and Median Frequency(MF) for representing muscle contraction and fatigue was retrieved from high G-training on a human centrifuge simulator. A total of 19 trainees out of 47 trainees of the Korean Air Force fell into G-LOC condition during the training in attaching EMG sensor to three body parts(neck, abdomen, calf). IAV, MAV, WL, and ZC under condition after G-LOC were decreased by 17 %, 17 %, 18 %, and 4 % comparing to those under condition before G-LOC respectively. Also, RMS, IAV, MAV, and WL in neck part under condition after G-LOC were higher than those under condition before G-LOC; while, those in abdomen and calf part lower. This study suggest that measurement of IAV and WL by attaching EMG sensor to calf part may be optimal for predicting G-LOC.

• Journal of Biomedical Engineering Research
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• v.22 no.3
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• pp.249-257
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• 2001

The voluntary contracted EMG signal of spinal cord injured patients is very small because the information from central nervous system is not sufficiently transmitted to $\alpha$ motor neuron or muscle fiber. Therefore the acquisited EMG signal from needle or surface electrodes can not be identified obvious voluntary contraction pattern by muscle movement. In this paper we propose the extraction technique of voluntary muscle contraction and relaxation pattern from EMG signal of spinal cord injured patient whose EMG signal is composed of the linear sum of mo색 unit action potentials with two noise sources, additive noise assumed to be white Gaussian noise and high frequency discharge assumed to be not motor unit action potential but impulsive noise. In order to eliminate impulsive noise and additive noise from voluntary contracted EMG signal, we use the FatBear filter which is a nonarithmetic piecewise constant filter, and multiscale nonlinear wavelet denoising processing, respectively. The proposed technique is applied to the EMG signal acquisited from transverse myelitis patients to extract voluntary muscle contraction pattern.

• Journal of Korean Physical Therapy Science
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• v.7 no.2
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• pp.663-682
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• 2000

The purpose of this study was to identify the superior exercise on the reduction of low back pain, between the Mckenzie exercise and the williams exercise. 24 chronic low back pain patients were randomly divided into 3 groups (Mckenzie exercise group = 8, williams exercise group = 8, control group = 8). Each group examined using the Borg scale in a reduction of low back pain, the EMG amplitude in a stationary sit-up position and in a stationary 1000 back extension position. The Results are as follow. 1. After the training period, the Mckenzie exercise group and the williams exercise group revealed reduction of low back pain, but the control group does not revealed it. 2. After the training period, there were no significant differences on the reduction of low back pain between the Mckenzie exercise group and the williams exercise group. 3. After the training period, no groups decreased on the abdominal muscle EMG amplitude. 4. After the training period, all groups revealed no significant differences on the abdominal muscle EMG amplitude. 5. After the training period, all groups decreased on the low back muscle EMG amplitude. 6. After the training period, all groups revealed no significant differences on the low back muscle EMG amplitude. Overall, the study suggested that the Mckenzie exercise and the williams exercise achieve the same effect on the reduction of low back pain, and the fact seems to be influenced by other factors without muscular adaptation.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.1
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• pp.63-73
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• 2015

The purpose of this study was to examine EMG activities and VMO/VL ratio of the vastus medialis oblique, and vastus lateralis during step up exercise according to ankle and knee positions in soccer players with patellofemoral pain syndrome. Methods: Subject(patellofemoral pain syndrome, PFPS: n=8 and without PFPS, non PFPS; NPFPS: n=8) perfomed step up exercise at each knee and ankle position(knee flexion $30^{\circ}$, $60^{\circ}$, and $90^{\circ}$, ankle internal rotation $30^{\circ}$, neutral, and external rotation $30^{\circ}$) while EMG activity was collected. The EMG signals were expressed by the % maximal voluntary isometric Contraction(%MVIC) values. Statistical analysis consisted of two way repeated measures analysis of variance with post hoc analysis. Results: Main results were as follows: 1) EMG of VMO, and VL was tend to be lower in PFPS compared to NPFPS. 2) EMG of VMO and VL with knee flexrion $60^{\circ}$ was significantly higher the results with knee flexion $30^{\circ}$, and $90^{\circ}$. VMO and VL with ankle external rotation $30^{\circ}$ was significantly higher the results with internal rotation $30^{\circ}$ and neutral position. Conclusion: Considering the EMG activity was reduced due to the to the PFPS and that performing step up with knee flexion $60^{\circ}$ with ankle external rotation $30^{\circ}$ position may provide the most effective condition for patients with patellofemoral pain syndrome.