• Proceedings of the KOSOMBE Conference
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• v.1996 no.11
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• pp.99-102
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• 1996

The ultimate object of FES is on the recovering function of body and shape demaged from desease or injury to original state. On this study, object is recovering of gait function of the disabled who, especially, have gait disturbance. Paralyzed muscle from the central nerve disable, if peripheral nerves which be in the lower part of the harmed are activated, muscle contraction is possible. The traumatic trouble, peripheral nerves aren't connected to a central nerve but origin of peripheral nerve cells which are in the lower part of the harmed are alive, react on stimulation. We design 4-channel stimulator, being based on standard stimuli pattern. stimulator is manufactured with compact size and light weight to portable.

• The Journal of Korea Robotics Society
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• v.12 no.3
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• pp.270-278
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• 2017

The electrical muscle stimulator (EMS) based human machine interface (HMI) free to mechanical constraint and muscle fatigue problems are proposed for force feedback in a virtual reality. The device was designed to provide force feedback up to 4.8 N and 2.6 N each to the thumb and forefingers. The main objective of the HMI is to make unnecessary mechanical structures to attach on the hand or fingers. It employs custom EMSs and an interface arranged in the forearm. In this work, major muscle groups such as extensor pollicis brevis (EPB), extensor indicis proprius (EIP), flexor pollicis longus (FPL) and flexor digitorum profundus (FDP) are selected for efficient force feedback and controlled individually. For this, a human muscular-skeletal analysis was performed and verified. The validity of the proposed multi-channel EMS based HMI was evaluated thorough various experiments with ten human subjects, interacting with a virtual environment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.4
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• pp.819-825
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• 2003

The purpose of this study is to develop the speaker recognition system which can select one of operating modes in FES for general paralysis patients. As spiral injury by traffic accident, industrial disaster, or stroke has been increased, the development of FES(Functional Electrical Stimulator) system is urgent to prevent paralysis and atrophy, and to assist the patients walking. For these patients we developed FES system(1). To operate this system one of several operating modes must be selected. As this can not be done by general paralysis patients, an attempt has been tried in this study to select the mode by speaker recognition system. RSC-300 of sensory co. has been chosen as a speaker recognition chip, and PIC16F84 is adapted to interface RSC-300 and FES system.

• Asian Spine Journal
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• v.12 no.6
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• pp.973-980
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• 2018

Study Design: Retrospective review. Purpose: To identify the trends in stimulator use, pair those trends with various grafting materials, and determine the influence of stimulators on the risk of revision surgery. Overview of Literature: A large number of studies has reported beneficial effects of electromagnetic energy in healing long bone fractures. However, there are few clinical studies regarding the use of electrical stimulators in spinal fusion. Methods: We used insurance billing codes to identify patients with lumbar disc degeneration who underwent anterior lumbar interbody fusion (ALIF). Comparisons between patients who did and did not receive electrical stimulators following surgery were performed using logistic regression analysis, chi-square test, and odds ratio (OR) analysis. Results: Approximately 19% of the patients (495/2,613) received external stimulators following ALIF surgery. There was a slight increase in stimulator use from 2008 to 2014 (multi-level $R^2=0.08$, single-level $R^2=0.05$). Patients who underwent multi-level procedures were more likely to receive stimulators than patients who underwent single-level procedures (p<0.05; OR, 3.72; 95% confidence interval, 3.02-4.57). Grafting options associated with most frequent stimulator use were bone marrow aspirates (BMA) plus autograft or allograft for single-level and allograft alone for multi-level procedures. In both cohorts, patients treated with bone morphogenetic proteins were least likely to receive electrical stimulators (p<0.05). Patients who received stimulation generally had higher reimbursements. Concurrent posterior lumbar fusion (PLF) (ALIF+PLF) increased the likelihood of receiving stimulators (p<0.05). Patients who received electrical stimulators had similar revision rates as those who did not receive stimulation (p>0.05), except those in the multilevel ALIF+PLF cohort, wherein the patients who underwent stimulation had higher rates of revision surgery. Conclusions: Concurrent PLF or multi-level procedures increased patients' likelihood of receiving stimulators, however, the presence of comorbidities did not. Patients who received BMA plus autograft or allograft were more likely to receive stimulation. Patients with and without bone stimulators had similar rates of revision surgery.

• The Journal of Korean Physical Therapy
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• v.6 no.1
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• pp.171-183
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• 1994

Purphose. This present study examines the effect of brief, intense transcutaneous electrical nerve stimulation(BTENS) on sensory nerve conduction, electrical pain threshold, and two-point discrimination measured at the superficial radial nevre distribution in 20 healthy subjects. Subjects. Twenty volunteercs, (10 females and 10 males(age range : 20-38 years : $mean{\pm}SD\;:\;27.00{\pm}5.12$), only subjects without prior traumatological and pathological were eligible to participated in this study. Methods. Nerve conduction were determined for the right superficial radial nerve. Electrical pain threshold were determined for the right wrist ipsilateral to the site of BTENS. Small disc electrodes were attached to the surface of the skin stradding the end of the radius. Square wave electrical pulses were delivered from an isolated stimulator through a constant current device at a frequency of 2 Hz(5 ms pulse width). Two-point discrimination, measured on the sensory distribution of superficial radial nerve. BTENS was delivered using a Max-SD( Medical design co.) portable battery powered stimulator. A cicular Ag/AgCl electrode in contact with hypertonic saline gel was attached to the lateral(radial side) surface of the forearm. Results. No significant effects were observed between stimulation methods in the prestimulation cycle(multi-way ANOVA repeated measures : distal latency ; F1.14=0.332. amplitude ; F 0.80=0.445, pain threshold ; F0.06=0.940.2 point discrimination ; F1.50=0.236). Highly significant effects were observed time with the pretreatment and 6 posttreatment cycles(p<0.01). Mighty significants differences in nerve conduction and pain threshold were found using un multi-way ANOVA repeated measures among stimulation methods for each cycles(p<0.01). Conclusion and Discussion The authors concludes that both nerve conduction and pain threshold changes are associated with therapy (stimulation) level of BTENS.

• Science of Emotion and Sensibility
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• v.13 no.4
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• pp.703-710
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• 2010

In this study, a tactile stimulator was developed to resolve some problems from the previous version of the system such as system configuration, inappropriate stimulation control and additional problems. The developed tactile stimulator consists of control unit, drive unit and vibrator unit. The control unit was controlled by E-Prime software to generate appropriate vibration pulses. The drive unit supplies enough energy to the vibrator to generate effective stimulation pulses. The vibrator unit consists of small coin type vibrator and velcro, and was made to be attached at the hand easily. The developed tactile stimulator was designed by small-size, light-weight, low-power, simple-fabrication, max 35 channels and little delay time from instruction signal of E-Prime software to vibrator. The duration and magnitude of stimulation was controlled by 10 grades and the problems concerning stimulation control were compensated by wideband frequency ranges. Additionally, the electrical safety was ensured by low voltage operation. Vibrator was made to be attached on finger as well as on any part of the subject. Since this tactile stimulator is developed based on E-Prime software which is widely used in cognitive science, it is believed that this stimulator be suitable for the wide application of cognitive science study.

• International journal of thyroidology
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• v.11 no.2
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• pp.109-116
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• 2018

It is very important to identify recurrent laryngeal nerve (RLN) and prevent RLN injury during thyroid surgery. The intraoperative neuromonitoring (IONM) for the prevention of RLN injury is a useful method because it can identify the location and status of RLN and predict postoperative vocal cord function easily. The IONM consists of a stimulating side that applies electrical stimulation to the nerve and a recording side that measures the surface electromyography (EMG) of the vocal cord muscle through electrode endotracheal tube. The nerve stimulator and surgical dissector are separate instruments. So, during IONM for the prevention of the RLN injury in conventional, endoscopic, or robotic thyroid surgery, repeated exchanging between surgical instruments and the nerve stimulator is inconvenient and time consuming. On the recording side, the accuracy of the electrode endotracheal tube which measures the EMG of the vocalis muscle can be affected by contact with between electrode and vocal fold and position change of patient. We would like to introduce recent several researches to overcome the current limitations of IONM.

• Journal of Biomedical Engineering Research
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• v.24 no.6 s.81
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• pp.523-531
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• 2003

We developed a PC-based 8-channel electrical stimulation system for transcutaneous functional electrical stimulation (FES), and applied it to FES exercise and paraplegic walking. The PC program consists of four parts: a database, a stimulation pattern generator, a stimulus parameter converter, and an exercise program. The stimulation pattern can be arbitrarily generated and edited by using the mouse on the PC screen, and the resulting stimulus parameters arc extracted from the recruitment curves, and transmitted to the 8-channel stimulator through the serial port. The stimulator has nine microprocessors: one master and eight slaves, Each channel is controlled by the slave microprocessor, and is operated independently. Clinical application of the system to a paraplegic patient showed significant increase in the knee extensor torque, the fatigue resistance, and the leg circumference, The patient can now walk about 50 meters for more than 2 minutes.

• Journal of Biomedical Engineering Research
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• v.20 no.2
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• pp.183-190
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• 1999

The purpose of this study was to develop a portable and convenient closed-loop contrel type electrical stimulator for patients with foot drop. This system restores walking movement as well as prevents from atrophy or necrosis of lower limb muscles and increases blood circulation in hemiplegic patients caused by traffic accident, industrial disaster or stoke. This system detects the changes of the ankle joint angle during walking, and then controls the stimulus intensity automatically to maintain the programmed level of the ankle joint angle. Also, this automatic system controls the stimulus intensity which is affected by increased electrode impedance resulting from long time use. The system detects the joint angle by an optical sensor and includes modified PID control which adjusts the stimulus intensity if the joint angle deviates from the preset value. Stimulus parameters are 30~80 volt, 40 Hz, and 0.2 ms. The system was applied to five hemiplegic patients for 42 days. Duration of stimulation was 15 min/day for the first week and then the duration was gradually increased to 30, 60, 90 and 120 min/day. The muscle force was increased up to 29.7%, muscle fatigue was decreased compared with the level before stimulation and the pattern of locomotion was improved. These results suggest that the electrical stimulator with closed-loop control type is more convenient and effective in restoration of locomotion of patients with foot drop than open-loop system.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.305-306
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• 2007

본 논문은 차세대 원전 신고리 #3, 4호기 NSSS(Nuclear Steam Supply System) 제어계통의 검증시스템을 개발하기 위한 설계개념에 관한 것이다. 차세대 원전 신고리 #3, 4호기는 KHNP(Korea Hydro & Nuclear Power Co., Ltd.)가 개발한 APR1400(Advanced Power Reactor 1400 [MWe])을 적용하는 최초의 원자력 발전소이다. APR1400은 3세대 원자력발전소로 인정받고 있으며, APR1400 원자력발전소의 안전한 운영을 위하여 I&C(Instrumentation and Control)시스템이 디지털 표준 플랫폼으로 설계되었다[2]. 특히, 차세대 원전 신고리 #3, 4호기의 비안전계통(제어 감시 및 경보계통)은 WEC (Westinghouse Electric Company)의 DCS(Distributed Control System) 상용 단일 플랫폼으로 구성될 예정이다. 우리는 신고리 #3, 4호기의 제어계통 중에서 NSSS(Nuclear Steam Supply System) 제어계통의 검증시스템을 개발하기 위하여 Stimulated Simulator의 방법론을 적용하여 "Simulator"라는 설계 개념을 정립하였다. 현재 원자력발전소 NSSS 제어계통의 DCS Stimulator 개발을 위하여 차세대 원전 신고리 #3, 4호기에 시설될 WEC의 DCS와 Simulation 서버 그리고 I/O 설비를 구축 중에 있으며, 원자력발전소 현장 기기 모델링 소프트웨어와 I/O 설비간의 인터페이스를 위한 동신 소프트웨어도 개발하고 있다.