• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.35 no.11
• /
• pp.1213-1217
• /
• 2011

Electric stimulators are used for various treatments, such as for pain relief and to improve rehabilitation in and out of the hospital. However, if the stimulation pulse affects the patient's heart, it can cause critical cardiac disorders such as arrhythmia or ventricular fibrillation. As a result, it must be ensured that the transmission length of the stimulation pulse does not exceed the proper range in the design of an electric stimulator. Furthermore, every anticipated risk factor must be monitored in in-vitro and in-vivo experiments. A new stimulator was designed to supply continuous 0.001 J stimulation pulses at a rate of 60 pulses per second. To evaluate the safety of the new electric stimulator and to measure its energy transfer and pulse transmission length, we built a conduction model that was filled with saline and measured the electric field at various positions in response to real stimulations. In an animal experiment with two pigs, heart disorders were induced by applying electric stimulation to tissues near the heart. These heart disorders were different from the result obtained with 9 V DC stimulation.

• Journal of Magnetics
• /
• v.17 no.1
• /
• pp.27-32
• /
• 2012

Transcranial magnetic stimulation requires an electric field composed of dozens of V/m to achieve stimulation. The stimulation system is composed of a stimulation coil to form the electric field by charging and discharging a capacitor in order to save energy, thus requiring high-pressure kV. In particular, it is charged and discharged in capacitor to discharge through stimulation coil within a short period of time (hundreds of seconds) to generate current of numerous kA. A pulse-type magnetic field is formed, and eddy currents within the human body are triggered to achieve stimulation. Numerous pulse forms must be generated to initiate eddy currents for stimulating nerves. This study achieved high internal pressure, a high number of repetitions, and rapid switching of elements, and it implemented numerous control techniques via introduction of the half-bridge parallel load method. In addition it applied a quick, accurate, high-efficiency charge/discharge method for transcranial magnetic stimulation to substitute an inexpensive, readily available, commercial frequency condenser for a previously used, expensive, high-frequency condenser. Furthermore, the pulse repetition rate was altered to control energy density, and grafts compact, one-chip processor with simulation to stably control circuit motion and conduct research on motion and output characteristics.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.18 no.6
• /
• pp.1723-1727
• /
• 2004

We investigated the activity and stability of alcohol dehydrogenase from horse liver (HLADH) under the electric stimulation. The activity and stability of alcohol dehydrogenase depended on electric output voltaqe, stimulation time, pulse duration and pulse interval, and temperature. HLADH retained about 23% of its activity in buffer but 78% in 10% trehalose solution under electric stimulation with 10V, 10min, The stabilizing of enzymes against electric stimulation by stabilizing additives showed a great potential use of enzymes in biotechnology and medical engineering fields.

• Journal of the Korean Chemical Society
• /
• v.48 no.2
• /
• pp.171-176
• /
• 2004

We investigated the activity and stability of alcohol oxidase from Hansenula sp. under the electric stimulation. The activity and stability of alcohol oxidase depended on electric output voltage, stimulation time, pulse duration and pulse interval. This inactivation of the enzyme under electric stimulation could be recovered by stabilizing additives such as sugars, polymers and hydrogels. The enzyme activity retained about 52% in 10% trehalose solution under electric stimulation with 40 V and 10 min. The stabilizing of enzymes against electric stimulation showed a great potential use of enzymes in biotechnology and medical engineering fields.

• Korean Journal of Agricultural Science
• /
• v.40 no.1
• /
• pp.13-18
• /
• 2013

Effect of electric pulse stimulation was tested on the fruit body formation of valuable mushroom Tricholoma matsutake in the field of natural habitat of this mushroom. After applying the electric stimulator to the specific area of pine forest we found that the treatment especially stimulated the fructification of T. matsutake. And the most valuable findings of our study was that only our treatment plots showed fruit body formation whereas the control plots and the whole natural habitats of our study area showed zero production of this mushroom during the same time. From the point of view of mushroom production, our experiment shows that fruit body production can be upgraded by using pulsed power as an electrical stimulation in the field of the natural habitat of this mushroom. These findings from our experiment confirm the effectiveness of the significance of pulsed power technology for the improvement of T. matsutake fruit body production in the natural habit of this mushroom.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.3
• /
• pp.729-736
• /
• 2010

In this study, a magnetic stimulation (MS) device with controllable pulse forming technology and pulse shape (MS) is described. The MS device uses an IGBT with appropriate snubbers to switch coil currents up to 6 kA, enabling pulse forming technology control from 5 s to over 100 s. The induced electric field pulses use 2% - 34% less energy and generate 57% - 67% less coil heating compared to matched conventional cosine pulses. MS is used to stimulate rhesus monkey motor cortex in vivo with pulse forming technology of 20 to 100 s, demonstrating the expected decrease of threshold pulse amplitude with increasing pulse forming technology. The technological solutions used in the MS prototype can expand functionality, and reduce power consumption and coil heating in MS, enhancing its research and therapeutic applications.

• Journal of Biomedical Engineering Research
• /
• v.28 no.1
• /
• pp.153-161
• /
• 2007

Stroke is the second most significant disease leading to death in Korea. The conventional therapeutic approach is mainly based on physical training, however, it usually provides the limited degree of recovery of the normal brain function. The electric stimulation therapy is a novel and candidate approach with high potential for stroke recovery. The feasibility was validated by preliminary rat experiments in which the motor function was recovered up to 80% of the normal performance level. It is thought to improve the neural plasticity of the nerve tissues around the diseased area in the stroked brain. However, there are not so much research achievements in the electric stimulation for stroke recovery as for the Parkinson's disease or Epilepsy. This study aims at the developments of a wireless variable pulse generator using ZigBee communication for future implantation into human brain. ZigBee is widely used in wireless personal area network (WPAN) and home network applications due to its low power consumption and simplicity. The developed wireless pulse generator controlled by ZigBee can generate various electric stimulations without any distortion. The electric stimulation includes monophasic and biphasic pulse with the variation of shape parameters, which can affect the level of recovery. The developed system can be used for the telerehabilitation of stroke patient by remote control of brain stimulation via ZigBee and internet. Furthermore, the ZigBee connection used in this study provides the potential neural signal transmission method for the Brain-Machine Interface (BMI).

• Journal of Embryo Transfer
• /
• v.8 no.2
• /
• pp.151-157
• /
• 1993

The present study was undertaken to determine the optimal condition for parthenogenetic activation of rabbit oocytes by electric stimulation in vitro in an attempt to develop nuclear transplantation techniques for cloning mammalian embryos and animals. Freshly ovulated oocytes were collected from superovulated rabbits from 13 to 26 hrs. after hCG injection. The cumulus-free oocytes were activated parthenogetically by repeated stimuli of square direct electric pulses in O.3M mannitol solution. After applying electric stimulations of different voltages, pulse durations and pulse times, all of the oocytes were cultured in TCM-199 with 10% FCS for 96 hours in a 5% $CO_2$ incubator, and their developmental potential in vitro was examined. The higher activation rate (68.9%) was achieved at the voltage of 2.0kv/cm, the pulse duration of 60 $\mu$sec and three pulse times and the activation rate of 100% was achieved at the pulse duration of 100 and 200 $\mu$sec, the voltage of 1.5kv/cm and three pulse times. Although the higher rates of activation of oocytes were achieved at 100 and 200 $\mu$sec, none of them developed to blastocyst in vitro. The oocytes collected 18~20 hours post hCG injection showed the highest rate of activation and development to blastocyst in vitro than the oocytes collected 13~15 or 25~26 hours post hCG injection. Therefore, it can be suggested that the application of electric stimulation of 2.0kv/cm, 60 $\mu$sec and three pulse times to the oocytes collected at 18~20 hours post hCG injection would be more beneficial for the parthenogenetic activation of oocytes in rabbits.

• Proceedings of the KOSOMBE Conference
• /
• v.1992 no.05
• /
• pp.198-202
• /
• 1992

In this paper, we have performed an experiment to obtain an optimized electric stimulation condition on the tip or a ringer skin. The desired parameters for stimulation of the finger tip skin are waveforms, frequency, stimulation intensity, duty cycle. As a result, when the finger skin was stimulated with monophasic, biphasic, and differntial phasic, the most appropriate condition was 200 to 250[Hz] in frequency, 10 to 25[%] in duty cycle. Burst type pulse was more sensitive effect than that of continuous pulse methode.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.65 no.1
• /
• pp.25-30
• /
• 2016

In this paper, personal electrical stimulation medcial devices using bioelectrical stimulating was developed. Therapy effect of RET(resistive electric transfer) was more effective than CET(capacitive electric transfer), but CET was adopted because of safety issue. Then, the optimum parameters that may be effective in thin skin or facial wrinkles was set. For example, the frequency of the pulse voltage for stimulation is 1.8[MHz], burst frequency is 7[kHz] or 400[Hz], the development of devices was to have ON/OFF control and frequency control. When burst frequency was adjusted 7[kHz], heat was generated in the electrode. The case of 400[Hz] the heat was little generated. The microcontroller ATmega128-based experimental results show that the proposed personal high frequency electrical stimulation devices can be applied to medical equipment using therapy effect successfully.