• Journal of Sensor Science and Technology
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• v.16 no.5
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• pp.369-376
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• 2007

Recently, obesity that is increasingly becoming a major cause of various diseases is emerging as a serious social problem. In order to solve this problem, the necessity of measurement systems for overweight management has increased. This paper is a study on the measurement system for obesity management that can offer right medical services everywhere and allways by analyzing EMG (electromyograph) of the abdomen and then checking one's health state. For analyzing EMG signals of the abdomen, algorithms for energy detection, signal feature extraction, classification and recognition are presented. This paper proposes a system that provides an appropriate an estimation on the health status by evaluating the obesity degree and muscular strength of the abdomen through the system applying these algorithms.

• Journal of Biomedical Engineering Research
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• v.22 no.2
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• pp.171-178
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• 2001

본 연구에서는 강건 시지연추정 알고리즘을 바탕으로 하여 표면근전도 신호로부터 새로운 근섬유 전도속도 측정방법을 제안하였다. 제시한 방법은 가우시안 가정 하에서 유도된 기존의 방법들로는 불가능한 비가우시안 충격성잡음을 포함하는 표면근전도 신호를 대상으로도 정확하게 근섬유 전도속도를 측정할 수 있다. 제시한 방법의 평가를 위하여 먼저, 마미총 증후군에 걸린 근질환자의 근전도 신호가 비가우시안 $\alpha$-stable 확률분포로 모델링할 수 있음을 보였으며, 정상인과 근질환자 6명의 피검자로부터 족저단신근과 내측광근에서 각각 근전도 신호를 수집하여 실험한 근섬유 전도속도 측정결과를 타 연구자들과 비교, 평가하였다. 실험결과, 족저단신근의 경우 근섬유 전도속도가 평균 4.60$\pm$0.50m/s로 내측광근의 경우 5.66$\pm$0.59m/s로 각각 구할 수 있었다.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.738-741
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• 1988

In this paper, we deal with the movements identification of EMG signals by LPC cepstrum coefficients. Movements were identified by extration of characteristics of similar patterns in Euclid distance measurement method for EMG signals generated by voluntary contractions of subject's musculature. As number of coefficients is larger, we obtain the better rate of movements identification. By exact extraction of signals and decision of optimal coefficient, it is expected that these results will apply to prosthesis control in real-time.

• Journal of Biomedical Engineering Research
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• v.6 no.1
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• pp.19-30
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• 1985

This paper describes the EMG signals in frequency domain using power spectral density, The changes in the moan frequency can represent the energy distribution which results from changing in load before and during fatigue. Most of EMG signal power spectrum is located between 10 and 200Hz. Shifts of the high-energy regions of the power spectra can be inferred from the changes in the mean frequency. If the load is increased without fatigue-ocurring, the high frequency regions have more energy than the low frequency regions. And if load is increased during fatigue, the low frequency regions have more energy than the high frequency regions.

• Journal of Biomedical Engineering Research
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• v.32 no.3
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• pp.191-197
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• 2011

Lifting chair is a typical assistive product to aid for standing up and sitting down for persons with disability. It is particularly useful for the elderly persons whose muscular system is weakened by degenerative joint disease. This paper describes biomechanical assessments of lifting chair with hip-up function. In experiments we measured 3D motion and electromyographic(EMG) signal on the femoral muscle when subject performs the standing motion on the predetermined seat height. Based on assessment of the standing motion, we select the hip-up angle as 15 degrees to cover the relative femoral angle when EMG peak value is appeared. Using an implemented prototype lifting chair with hip-up function we perform standing experiments with five subjects. The experimental results show that the lifting and hip-up functions are effective to assist for standing up motion with less muscle force.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.10 no.3
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• pp.92-97
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• 2011

In this paper, a controller recognizing human gestures using EMG signal is shown. The tiny and band-type controller is developed for image training to excercise the specific area in the body, and uses a dry-type silver fiber electrode easy to be attached or detached itself to a skin. The captured EMG signals are converted to 10-bit digital values via amplification and frequency filtering processes within the controller, and are transmitted to the server by wireless. As the gesture recognition ratio using the proposed controller on biceps is up to 80%, we expect the practical potential of the controller is very promising.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.1
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• pp.55-63
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• 2003

In this study was proposed that a new estimating method for investigation of contractile state changes which generated from continuous isometric contraction of skeletal muscle. The physiological changes(EMG, ECG) and the psychological changes by CNS(central nervous system) were measured by experiments, while the muscle of subjects contracted continuously with isometric contraction in constant load. The psychological changes were represented as three-step-change named 'fatigue', 'pain' and 'sick(greatly pain)' from oral test, and the method which compared physiological change with psychological change on basis of these three steps was developed. The result of analyzing the physiological signals, EMG and ECG signal changes were observed at the vicinity of judging point in time of psychological changes. Namely, it is supposed that contractile states have three kind of states pattern (stable, fatigue, pain) instead of two states (stable, fatigue).

• Journal of Biomedical Engineering Research
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• v.17 no.4
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• pp.459-468
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• 1996

This paper considers the problem of realising a parallel EMG identifier used in FES (functional electrical stimulation) system on a fixed dimension transputer array. This involves using an identifiestion algorithm in the wavelet transform domain. This algorithm have suggested by the authors in a previous paper(6). The transputer serial links permit higtlly varied and economic network-type connections and the structure enables rapid topological reconfiguration. Analysing the results Showed that the Speed-UPS ranged from 1.82 to 3.44 With 2-4 transputers for corresponding model order, and from 1.82 to 3.97 with increasing the model orders when two and four transputers are used respectively.

• Journal of the Korean Society of Physical Medicine
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• v.6 no.3
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• pp.323-330
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• 2011

Purpose : The purpose of this study was to examine the effects of using a pressure bio-feedback unit (PBFU) and a pelvic belt (PB) on the electromyographic (EMG) signal amplitude of the gluteus medius (Gmed) and the quadratus lumborum (QL) during hip abduction exercise when lying on the side. Methods : Twenty able-bodied volunteers (10 male, 10 female) were recruited for this study. The EMG signal amplitude was randomly measured during hip abduction with preferred hip abduction (PHA), with PBFU, and with PB. The surface EMG signal was recorded from the Gmed and the QL. Data were analyzed using a one-way repeated ANOVA. Results : Muscle activity of Gmed was significantly higher in PBFU and in PB than in PHA (p<.05). There were no significant difference between PBFU and PB(p>.05). Muscle activity of the QL was significantly lower in PB than in PHA(p<.05). The Gmed/QL muscle activity ratio was also significantly higher in PBFU and in PB than in PHA(p<.05), with no significant difference between PBFU and PB (p>.05). Conclusion : Based on these findings, using a PBFU and a PB is an effective method to disassociate QL use from Gmed use during hip abduction exercises when lying on the side.

• Journal of the Ergonomics Society of Korea
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• v.29 no.3
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• pp.357-364
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• 2010

This study proposes a lower-limb exoskeleton system that is controlled by a wearer's muscle activity. This system is designed by following procedure. First, analyze the muscle activation patterns of human leg while walking. Second, select the adequate actuator to support the human walking based on calculation of required force of knee joint for step walking. Third, unit type knee and ankle orthotics are integrated with selected actuator. Finally, using this knee-assistive system (KAS) and developed muscle stiffness sensors (MSS), the muscle activity pattern of the subject is analyzed while he is walking on the stair. This study proposes an operating algorithm of KAS based on command signal of MSS which is generated by motion intent of human. A healthy and normal subject walked while wearing the developed powered-knee exoskeleton on his/her knees, and measured effectively assisted plantar flexor strength of the subject's knees and those neighboring muscles. Finally, capabilities and feasibility of the KAS are evaluated by testing the adapted motor pattern and the EMG signal variance while walking with exoskeleton. These results shows that developed exoskeleton which controlled by muscle activity could help human's walking acceptably.