• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.6
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• pp.132-140
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• 2008

Conventional rectal catheters which are used for the measurement of abdominal pressure can cause erroneous result affecting detrusor pressure, and the catheter itself is not comfortable to the patients. To reduce these problems, we invented a new method for measuring abdominal pressure in non invasive manner using surface electromyography (EMG) signals of the rectus abdominis muscle. Our results showed that the correlation coefficient and root mean square error (RMSE) between the measured abdominal pressures by the conventional rectal catheters and the estimated values by our proposed algorithm were $0.79{\pm}0.06$ and $0.10{\pm}0.07$, respectively. These findings suggest that the surface EMG of rectus abdominis muscle might be used indirectly for more convenient measurement of abdominal pressure on ambulatory urodynamic study.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.10
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• pp.2317-2323
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• 2010

When the muscle is contracted by continuous and same, the force takes fatigue and stiffness. The aim of this study was to know how the fatigue and muscle stiffness change during an isometric contraction. Surface Electro myography(EMG) signal monitoring system and ultrasonic transducer set up the same muscle stem, subjects contract his right femoris muscle by submaximal isometric contraction(50% of MVC) until exhaustion. Before and after the test, muscle stiffness was measured and EMG was measured during the contraction. As time goes by, muscle fatigue was increased. and the stiffness was shown strongly after the contraction. These results show if the muscle becomes more and more fatigued, the circulation of muscle is delayed although the contraction doesn't happen. So muscle stiffness is increased.

• Journal of Biomedical Engineering Research
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• v.32 no.1
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• pp.45-54
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• 2011

Cuff electrodes have a benefit for chronic electroneurogram(ENG) recording while minimizing nerve damage. However, the ENG signals are usually contaminated by electromyogram(EMG) activity from the surrounding muscle, the thermal noise generated within the source resistance, and the electric noise generated primarily at the first stage of the amplifier. This paper proposes a new cuff electrode to reduce the interference of EMG signals. An additional middle electrode was placed at the center of cuff electrode. As a result, the proposed cuff electrode achieved a higher signal-to-interference ratio compared to the conventional tripolar cuff. The cuff electrode was then assembled together with closure, headstage, and hermetic case including electronic circuits. This paper also presents a lownoise amplifier system to improve signal-to-noise ratio. The circuit was designed based on the noise analysis to minimize the electronic noise. The result shows that the total noise of the amplifier was below $1{\mu}V_{rms}$ for a cuff impedance of $1\;k{\Omega}$ and the common-mode rejection ratio was 115 dB at 1 kHz. In the current study, the performance of nerve cuff electrode system was evaluated by monitoring afferent nerve signals under mechanical stimuli in a rat animal model.

• Korean Journal of Veterinary Research
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• v.38 no.1
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• pp.183-199
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• 1998

The effects of electroacupuncture(EA) on gastrointestinal motility were investigated in 6 horses. Three acupuncture points ; Guan Yuan Shu(BL-26), Wei Shu(BL-21) and Da Chang Shu(BL-25) were stimulated for 20 minutes by EA at separate occasions under varying condition ; 2V-1Hz, 2V-5Hz, 2V-30Hz, 4V-1Hz, 4V-5Hz and 4V-30Hz. Myoelectric activity of stomach and cecum was monitored to investigate the gastrointestinal motility. Electromyogram(EMG) recordings were carried out before, 0, 20 minutes after and 40 minutes after the EA stimulation. EMG bipolar electrode was surgically implanted in seromuscular layer of greater curvature in the stomach and between medial band and ventral band in the cecum. The EA stimulation and monitoring were not commenced until 15 days after electrode implantation. The EA stimulation of Wei Shu influenced on stomach motility and that of Da Chang Shu on, cecum motility. However, the EA stimulation of Guan Yuan Shu influenced on both the stomach and the cecum motility. The myoelectrical spike burst amplitude of the stomach and the cecum was significantly(p<0.05) increased by 2V-1Hz stimulation, but the myoelectrical spike burst frequence of the stomach and the cecum was significantly decreased by 2V-30Hz or 4V-30Hz stimulation. The myoelectrical spike burst duration of the stomach and the cecum was significantly lengthened by 4V-30Hz and 2V or 4V-30Hz stimulation, respectively.

• Journal of the Institute of Convergence Signal Processing
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• v.24 no.3
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• pp.134-139
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• 2023

Rehabilitators perform outpatient treatment and daily rehabilitation exercises to recover physical function with the aim of quickly returning to society after surgical treatment. Unlike performing exercises in a hospital with the help of a professional therapist, there are many difficulties in performing rehabilitation exercises by the patient on a daily basis. In this paper, we propose a CNN-LSTM-based upper limb rehabilitation real-time monitoring system so that patients can perform rehabilitation efficiently and with correct posture on a daily basis. The proposed system measures biological signals through shoulder-mounted hardware equipped with EMG and IMU, performs preprocessing and normalization for learning, and uses them as a learning dataset. The implemented model consists of three polling layers of three synthetic stacks for feature detection and two LSTM layers for classification, and we were able to confirm a learning result of 97.44% on the validation data. After that, we conducted a comparative evaluation with the Teachable machine, and as a result of the comparative evaluation, we confirmed that the model was implemented at 93.6% and the Teachable machine at 94.4%, and both models showed similar classification performance.

• Journal of Korea Multimedia Society
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• v.21 no.5
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• pp.609-616
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• 2018

In this paper, we designed a multimodal bio-signal measurement system to observe changes in the brain nervous system and vascular system during sleep. Changes in the nervous system and the cerebral blood flow system in the brain during sleep induce a unique correlation between the changes in the nervous system and the blood flow system. Therefore, it is necessary to simultaneously observe changes in the brain nervous system and changes in the blood flow system to observe the sleep state. To measure the change of the nervous system, EEG, EOG and EMG signal used for the sleep stage analysis were designed. We designed a system for measuring cerebral blood flow changes using functional near-infrared spectroscopy. Among the various imaging methods to measure blood flow and metabolism, it is easy to measure simultaneously with EEG signal and it can be easily designed for miniaturization of equipment. The sleep stage was analyzed by the measured data, and the change of the cerebral blood flow was confirmed by the change of the sleep stage.

• Journal of the Korean Society of Physical Medicine
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• v.18 no.3
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• pp.73-84
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• 2023

PURPOSE: This study analyzed the impact of AI and biosensors on physical therapy, identifying the stage of customized technology development and future prospects. AI and biosensors improve the efficiency, establish customized treatment plans, and expand patient treatment opportunities. The study employed a literature review by searching databases and collecting research. METHODS: This study searched various databases related to the topic, collected existing research, papers, and reports, evaluated the literature, and summarize the results. RESULTS: Exercise therapy utilizing artificial intelligence can provide personalized and optimal exercise plans while monitoring rehabilitation progress. In addition, biosensors such as EMG sensors and accelerometers can monitor the individual progress in physical therapy, particularly in stroke patients, which can help improve physical therapy strategy and promote patient recovery. CONCLUSION: This study suggested that artificial intelligence can be applied in many areas of physical therapy, such as exercise therapy, customized treatment plans, rehabilitation and management, pain management, neuro rehabilitation, and auxiliary devices. Using AI technology, it is possible to analyze and improve exercise and posture, retrain the central nervous system, establish customized treatment plans for individual patients, predict and compare patient progress before and after treatment, and provide customized pain analysis and treatment methods. In addition, AI can provide neuro rehabilitation programs and customized auxiliary devices.

• Journal of Industrial Technology
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• v.43 no.1
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• pp.25-31
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• 2023

Stretchable and flexible electronics that comply with dynamic movements and micromotion of the human tissues can enable real-time monitoring of physiologic signals onto the human skin and in the brain, respectively. Especially, gallium based liquid metal stretchable electronics can offer human-interactive biosensors to monitor various physiologic parameters. However, the liquid-like nature, surface oxidation and contamination by organic materials, and low biostability of the liquid metals have still limited the long-term use as bioelectronics. Here we introduced electrochemical deposition without oxidation pathways to overcome these practical challenges in liquid metal bioelectronics. CNT/PDDA composite with reduction way and PEDOT:BF₄ with oxidation way under organic solvent are suggested as rationally designed material engineering approaches. We confirmed that the structures with the soft, flexible, and stretchable liquid metal platform can successfully detect dopamine with a high sensitivity and selectivity, record neural signals including action potentials without scar formation, and monitor physiologic signals such as EMG and ECG.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.4
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• pp.470-476
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• 2018

Facial motor evoked potential (FMEP) by multi-pulse transcranial electrical stimulation (mpTES) can complement free-running electromyography (EMG) and direct facial nerve stimulation to predict the functional integrity of the facial nerve during cerebello-pontine angle (CPA) tumor surgery. The purpose of this paper is to examine the standardized test methods and the usefulness of FMEP as a predictor of facial nerve function and to minimize the incidence of facial paralysis as an aftereffect of surgery. TES was delivered through electrode Mz (cathode) - M3/M4 (anode), and extracranially direct distal facial muscle excitation was excluded by the absence of single pulse response (SPR) and by longer onset latency (more than 10 ms). FMEP from the orbicularis oris (o.oris) and the mentalis muscle simultaneously can improve the accuracy and success rate compared with FMEP from the o.oris alone. Using the methods described, we can effectively predict facial nerve outcomes immediately after surgery with a reduction of more than 50% of FMEP amplitude as a warning criterion. In conclusion, along with free-running EMG and direct facial nerve stimulation, FMEP is a useful method to reduce the incidence of facial paralysis as a sequela during CPA tumor surgery.

• Journal of Electrodiagnosis and Neuromuscular Diseases
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• v.20 no.2
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• pp.98-105
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• 2018

Objective: To evaluate whether the increase of the amplitude of motor evoked potentials (MEPs) during surgery can imply favorable prognosis postoperatively in spinal cord tumor surgery. Method: MEPs were monitored in patients who underwent spinal cord tumor surgery between March 2016 and March 2018. Amplitude changes at the end of monitoring compared to the baselines in limb muscle were analyzed. Minimum and maximum changes were set to $MEP_{min}$ (%) and $MEP_{max}$ (%). Strengths of bilateral 10 key muscles which were documented a day before ($Motor_{pre}$), 48 h ($Motor_{48h}$) and 4 weeks ($Motor_{4wk}$) after the surgery were reviewed. Results: Difference of $Motor_{48h}$ from $Motor_{pre}$ ($Motor_{48h-pre}$) and $Motor_{4wk}$ from $Motor_{pre}$ ($Motor_{4wk-pre}$) positively correlated with $MEP_{min}$, suggesting that smaller the difference of MEPs amplitude, less recovery of muscle strength. There was a negative correlation between the amount of bleeding and $MEP_{min}$, indicating that the greater the amount of bleeding, the smaller the $MEP_{min}$, implying that MEPs amplitude is less likely to improve when the amount of bleeding is large. It also showed significant difference between patients with improved or no change of motor status and patients with motor deterioration after surgery according to anatomical tumor types. Conclusion: Improve of muscle strength was less when the increase of MEPs amplitude was small, and improvement of MEPs amplitude was less when the amount of bleeding was large. Correlation between changes of status of muscle strength after surgery and tumor types was observed. With amplitude increase in MEPs monitoring, restoration of muscle strength can be expected.