• 대한전자공학회논문지
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• 제27권2호
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• pp.126-134
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• 1990

본 논문에서는 3전극법으로 피검자의 이두박근과 삼두박근에서 검출한 표면 근전도 신호를 LPC 켑스트럼 계수를 이용하여 유클리드 및 가중 켐스트럼 거리 측정법을 통하여 8가지 팔 운동에 대한 기능분리 및 판별 인식에 관한 실험을 하였다. 유클리드 켑스트럼 거리 측정법의 경우,계수의 수가 8,10,12,14 등으로 증가함에 따라 동작기능 인식률도 각각 94.69, 95.63, 96.56, 96.88[%]로 증가하였으나 인식률의 증가폭은 상대적으로 적으며 가중 켑스트럼 거리 측정법의 경우에는 각각 91.88, 95, 99.69, 96.63[%]의 인식률을 보였다.

• 한국전문물리치료학회지
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• 제16권1호
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• pp.1-9
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• 2009

An abdominal drawing-in maneuver (ADIM) with a pressure biofeedback unit can be used to prevent excessive lumbar lordosis during bridging exercise. Therefore, in this research, the effects of an ADIM on lumbar lordosis and lower extremity muscle activity during bridging exercise were investigated in thirty healthy adults. Surface electromyography (EMG) and VICON system were used to collect kinematic data and muscle activity, respectively. A paired t-test was used to determine a statistical significance. The results showed as follows: (1) When performing bridging exercise with an ADIM, the height of the anterior superior iliac spine and greater trochanter decreased significantly (p<.05). (2) When performing bridging exercise with an ADIM, the trunk extension angle and pelvic angle increased significantly (p<.05). (3) When performing bridging exercise with an ADIM, the EMG signal amplitude increased significantly in the rectus abdominis, internal oblique abdominis, external oblique abdominis, medial hamstring, and lateral hamstring (p<.05). (4) When performing bridging exercise with an ADIM, the EMG signal amplitude decreased significantly in the erector spinae (p<.05). From the result of this research, an ADIM trained with pressure biofeedback unit during bridging exercise is effective to prevent excessive contraction of erector spinae, to limit excessive motion of pelvis from sagittal plane and to increase muscle activity of abdominal muscles and hamstring muscle.

• 한국산학기술학회논문지
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• 제19권8호
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• pp.260-267
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• 2018

표면근전도(sEMG) 신호의 응용은 초기에는 단순히 근육 활성도의 유무를 판별하여 On/Off 의 스위치 기능으로 많이 사용되어 왔으나, 표면근전도 신호처리와 알고리즘의 발달로 휠체어의 방향 제어는 물론 수화를 인식하는 분야까지 확대되었다. 청각 장애인들의 언어 소통을 위한 중요한 수단인 수화나 지화는 미학습자와는 소통의 어려움이 존재해왔으며, 이러한 어려움을 해결하기 위해 수화나 지화를 인식하는 기술에 대한 연구가 지속적으로 수행되어 왔다. 최근에는, 수화나 지화 시연시에 활성화되는 근육의 신호를 활용하여 수화나 지화를 인식하는 방법이 중국 숫자지화 중심으로 적용되고 있는 추세이다. 하지만, 수화나 지화는 일반 음성언어와 마찬가지로 중국 숫자지화와 한국 숫자지화가 다르므로, 중국 숫자지화 시연시에 관여하는 근육이 한국 숫자지화 시연시에는 관여하지 않을 수가 있어, 인식률이 현저히 떨어질 수 있다. 그러므로 한국 숫자지화 시연시에 활성화되는 근육의 선정은 표면근전도 신호에 기반한 한국 숫자지화 인식률에 매우 중요하다. 하지만, 표면근전도 신호에 기반한 한국 숫자지화 인식에 대한 연구는 문헌에서 드물다. 본 연구에서는 표면근전도 신호를 활용한 한국수화 또는 한국지화의 인식에 관한 초기 연구로서, 한국 숫자지화를 시연시에 관여하는 아래팔근육을 제안하고 실험을 통하여 검증하기 위해 숫자 영(0)부터 다섯(5)의 여섯 가지 한국 숫자지화를 대상으로 인식하는 연구를 수행하였다. 이를 위해, 표면근전도 신호를 활용한 CNN 기반 지화인식 방법에 적용하여 여섯 가지 한국 숫자지화에 대하여 100%의 인식률을 확인함으로써, 여섯 가지 한국 숫자지화 인식을 위해 제안된 아래팔근육과 전극위치의 타당성을 검증하였다.

• The Journal of Korean Physical Therapy
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• 제14권4호
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• pp.487-497
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• 2002

The fatigue process of the triceps surae was evaluated during a standing heel-rise test, comparising of pre-fatigue and post-fatigue. Sixteen healthy subjects with a mean age of 22.88 years participated. The heel-rise test was performed until exhaustion, and electromyographic activity expressed as mean value and root mean square of the gastrocnemius and soleus muscles were calculated. The average number of heel-rise performed was 63.69$\pm$26.10. The result of this present study indicate that the EMG signal is sensitive to the different muscle fatigue. Mean value and RMS decreased significantly in after fatigue. Significant difference were found between the pre-fatigue and post-fatigue in the total subjects. But there were no significant changes in mean and RMS between the male and female during standing heel-rise test. The present results, showing decreased EMG signal in the triceps surae, could be used as reference when testing the fatigue process in different clinical conditions. Recommendations for standardization of a heel-rise test are given.

• 제어로봇시스템학회논문지
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• 제15권2호
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• pp.163-168
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• 2009

In this study, we would be developed the fuzzy controlled PGO that controlled the flexion and the extension of each PGO's hip joint using the bio-signal and FSR sensor. The PGO driving system is to couple the right and left sides of the orthosis by specially designed hip joints and pelvic section. This driving system consists of the orthosis, sensor, control system. An air supply system of muscle is composed of an air compressor, 2-way solenoid valve (MAC, USA), accumulator, pressure sensor. Role of this system provide air muscle with the compressed air at hip joint constantly. According to output signal of EMG sensor and foot sensor, air muscles and assists the flexion of hip joint during PGO gait. As a results, the maximum hip flexion angles of RGO's gait and PGO's gait were about $16^{\circ}\;and\;57^{\circ}$ respectively. The maximum angle of flexion/extention in hip joint of the patients during RGO's gait are smaller than normal gait, because of the step length of them shoes a little bit. But maximum angle of flexion/extention in hip joint of the patients during PGO's gait are larger than normal gait.

• 한국운동역학회지
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• 제29권3호
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• pp.167-172
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• 2019

Objective: The aim of this study was to investigate the effect of midsole hardness of running shoe on muscle fatigue and impact force during distance running. Method: Ten healthy college recreational runners who were performing distance running at least three times a week participated in this experiment. They were asked to run for 15 minutes in the treadmill at 10 km/h with running shoes having three different types of midsole hardness (Soft, Medium, Hard). EMG signal and insole pressure were collected during the first and last one minute for each running trials. Data were analyzed using a one-way analysis of variance (ANOVA) with repeated measures. Results: Midsole hardness did not affect the consistency of stride length. For the median frequency of the EMG signal, only VL was affected by midsole hardness; that of medium was greater than other midsoles (p<.05). The loading rate of impact forces increased by midsole hardness (p<.01). Conclusion: Although soft midsole could attenuate impact forces at heel contact, it might have a negative effect on the fatigue of muscle which could decelerate the body after heel contact. Therefore, it is necessary to select the optimum hardness of midsole carefully for both reduction impact forces and muscle fatigue.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.246-249
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• 2004

The purpose of this study was to investigate the characteristics between EMG timing of muscle contraction and motor impairment in chronic hemiplegic stroke patients. Delay time and co-contraction of 4 patients who had stroke less than 3 years were measured during isometric wrist flexion and extension along the 3 seconds beep signal. Onset and offset of muscle contraction were significantly delayed on the more affected sides than control sides. Offset was significantly delayed than the onset on the affected sides in wrist flexion. Also, recruitment of antagonist was larger than agonist on the affected sides. Co-contraction ratio on the affected side was significantly smaller than control sides in wrist flexion. In affected sides, Fugl-Meyer motor assessment(FMA) shows the correlation of onset delay in wrist flexion and extension. However, co-contraction ratio correlated with FMA in wrist flexion. EMG assessment is likely to be useful outcome measure and provide insights into mechanism for motor recovery in stroke patients.

• 대한의용생체공학회:의공학회지
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• 제32권1호
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• pp.1-6
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• 2011

An active training system has been developed to assist the upper extremity function in patients with spasticity. We also evaluated the performance of the developed assistive system in five normal subjects and one hemiplegic patient. The maximum voluntary contraction (MVC) tests for biceps brachii and triceps brachii were performed and the relationship between linear enveloped EMG signal and the elbow joint torque was found. In order to implement an active training, our system was designed to allow isokinetic movement only when the subject generates elbow joint motion larger than the pre-fixed threshold level. The proposed EMG-feedback control method could provide active exercises, resulting in better rehabilitation protocol for spastic patients.

• 국제물리치료학회지
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• 제11권2호
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• pp.2065-2070
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• 2020

Background: Weakness of the abdominal and mid thoracic muscles the lead to thoracic kyphosis of stroke patients. The trunk muscles activity of stroke patients is significantly related to upper extremity. Objectives: To investigate the effect of seated exercise of thoracic and abdominal muscles on upper extremity function and trunk muscles activity in stroke patients. Design: One-group pretest-posttest design. Methods: A total of 27 stroke patients were recruited. All stroke patient were given seated abdominal exercise (posterior pelvic tilt exercises) and thoracic exercise (postural-correction exercise). All exercises were conducted for 30 minutes, three times a week for four weeks. The manual function test (MFT) and electromyography (EMG) were measured, and EMG electrodes were attached to thoracic paraspinal muscles and lower rectus abdominal muscles. EMG signal is expressed as %RVC (reference voluntary contraction). Results: Experimental group showed significant increases in abdominal muscles, paraspinal muscles activity and MFT total score, items of arm motion (forward elevation of the upper extremity, lateral elevation of the upper extremity, touch the occiput with the palm) in MFT after four weeks. Conclusion: These results suggest that, in stroke patients, seated exercise of thoracic and abdominal muscles contribute to improve trunk muscles activity and upper extremity function in stroke patients.

• 대한의용생체공학회:의공학회지
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• 제45권2호
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• pp.66-74
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• 2024

This study analyzed the occurrence of abnormal muscle coactivations based on the assistance of upper limb weight during reaching task in stroke patients. Nine chronic stroke survivors with hemiplegia performed reaching tasks using a programmable haptic robot. Electromyography (EMG) coactivation levels in the upper limb muscles were analyzed using a linear model describing the activation levels of two muscles when the patient's upper limb weight was assisted at 0%, 25%, and 50%. As the upper limb weight assistance of the haptic robot decreased, the magnitude of the EMG signal in both the deltoid and biceps muscles increased simultaneously on both the paretic and non-paretic sides. However, no difference was found between the paretic and non-paretic sides when comparing the slope of the linear model describing the activation relationship between the deltoid and biceps. The aforementioned results suggest that in some stroke survivors, the deltoids, triceps, and biceps on the paretic side may not be abnormally coupled when supporting the upper limbs against gravity. Furthermore, these results suggest that the combination of haptic robots and EMG analysis might be utilized for evaluating abnormal coactivations in stroke patients.