• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.81-84
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• 2001

In the power system of a satellite, solar array and a battery have directly impact on the life time of the satellite, and their stable operation is decided by whether their states are in the steady state operation or not. In this study, solar array capacity and battery characteristics of proposed communication satellite are designed and simulation is conducted according to the operation mode. Each operation mode is classified as the normal and worst case modes, respectively. The normal mode is analyzed under daylight and the eclipse with the EHT burn, and the worst case modes which have solar cell circuit failure, and battery cell failure are analyzed too.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.4
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• pp.490-494
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• 2014

In this paper, a design of high-speed power-off circuit and analysis. The incidence of high-dose transient radiation into the silicon-based semiconductor element induces the photocurrent due to the creation of electron-hole pairs, which causes the upset phenomenon of active elements or triggers the parasitic thyristor in the element, resulting in latch-up. High speed power-off circuit was designed to prevent burn-out of electronic device caused by Latch-up. The proposed high speed power-off circuit was configured with the darlington transistor and photocoupler so that the power was interrupted and recovered without the need for an additional circuit, in order to improve the existing problem of SCR off when using the thyristor. The discharge speed of the high speed power interruption circuit was measured to be 19 ${\mu}s$ with 10 ${\mu}F$ and 500 ${\Omega}$ load, which was 98% shorter than before (12.8 ms).

• The Journal of the Society of Korean Medicine Diagnostics
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• v.18 no.3
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• pp.217-223
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• 2014

Objectives This study is on the implementation of the electric cauterizer with the hole for acupuncture to achieve the superposition effect of acupuncture-moxibustion therapies. Methods In this paper, we especially made a hole across the heat terminal of the electric cauterizer for acupuncture. Before the cauterization, the doctor treats a patient with needle. And after acupuncture, the heat terminal is to be superposed upon the needle along the hole to add the cauterization. Results There are 2 coupling methods that the heat terminal is to be superposed with the needle; one is the top-coupling and the other is side-coupling. The top-coupling means that the heat terminal is to be superposed upon the needle along the top of the needle, and side-coupling means that the heat terminal is to be superposed to the needle along the side of the needle. Conclusion This study was aimed to implement the electric cauterizer with the hole for acupuncture to achieve the superposition effect of acupuncture-moxibustion therapies. Not electric acupuncture but manual acupuncture is adopted. The electric cauterizer generates the heat $38{\sim}45^{\circ}C$. This heat is safe for skin not to burn. The electric cauterizer constitutes the smokeless moxa- pad which effects the skin DDS.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05b
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• pp.8-11
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• 2003

We propose that when combustible burn with contain carbon, introduce fire detector with sensor of private-use detectable light energy as infrared and ultraviolet in energy of electromagnetic-wave type radiate from flame, method for correct discrimination to resemble fire produce false alarm of detector such as sun light, hot object radiation, are welding. This research using infrared sensor is pyroelectric infrared sensor based black body radiation theory. Ultraviolet sensor is uv Tron using gas multiplication effect to current discharge and photoelectric effect of metal. To have high sensibility and to gain proper output voltage, it has high responsive performance. This research introduced UV/IR compound type flame detector and proposed method of false alarm reduced to resemble fire. The result propres the prevention and extinction of fire technique degree, certificated operation of detector.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.4
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• pp.77-82
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• 2000

This paper describes the self healing characteristics of a metalized polypropylene film(MPPF) by voids under a.c condition. PDIVs were increased with the number of pre-self healing due to void defects, and several pre-self healing events took place at lower voltage than the critical breakdown voltage of a PPF. Self healing mainly occurred at pin tips, wrinkle sides, and cross points of wrinkles, and the main self healing voltage was increased with PPF thickness. The burn out area at self healing was increased with the applied voltage, and the peak currents in a grounding conductor at self healing was also increased with the applied voltage.

• Archives of Plastic Surgery
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• v.39 no.2
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• pp.138-142
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• 2012

Background : Electrical burns are one of the most devastating types of injuries, and can be characterized by the conduction of electric current through the deeper soft tissue such as vessels, nerves, muscles, and bones. For that reason, the extent of an electric burn is very frequently underestimated on initial impression. Methods : From July 1999 to June 2006, we performed 15 cases of toe tissue transfer for the reconstruction of finger defects caused by electrical burns. We performed preoperative range of motion exercise, early excision, and coverage of the digital defect with toe tissue transfer. Results : We obtained satisfactory results in both functional and aesthetic aspects in all 15 cases without specific complications. Static two-point discrimination results in the transferred toe cases ranged from 8 to 11 mm, with an average of 9.5 mm. The mean range of motion of the transferred toe was $20^{\circ}$ to $36^{\circ}$ in the distal interphalangeal joint, $16^{\circ}$ to $45^{\circ}$ in the proximal interphalangeal joint, and $15^{\circ}$ to $35^{\circ}$ in the metacarpophalangeal joint. All of the patients were relatively satisfied with the function and appearance of their new digits. Conclusions : The strategic management of electrical injury to the hands can be both challenging and complex. Because the optimal surgical method is free tissue transfer, maintenance of vascular integrity among various physiological changes works as a determining factor for the postoperative outcome following the reconstruction.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.44-45
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• 2010

We are currently conducting studies on culturing and biocompatibility assessment of various cells such as neural stem cells and induced pluripotent stem cells(IPS cells) on carbon nanotube (CNT), on nerve regeneration electrodes, and on silicon wafers with a focus on developing nerve integrated CNT based bio devices for interfacing with living organisms, in order to develop brain-machine interfaces (BMI). In addition, we are carried out the chemical modification of carbon nanotube (mainly SWCNTs)-based bio-nanosensors by the plasma ion irradiation (plasma activation) method, and provide a characteristic evaluation of a bio-nanosensor using bovine serum albumin (BSA)/anti-BSA binding and oligonucleotide hybridization. On the other hand, the researches in the case of "novel plasma" have been widely conducted in the fields of chemistry, solid physics, and nanomaterial science. From the above-mentioned background, we are conducting basic experiments on direct irradiation of body tissues and cells using a micro-spot atmospheric pressure plasma source. The device is a coaxial structure having a tungsten wire installed inside a glass capillary, and a grounded ring electrode wrapped on the outside. The conditions of plasma generation are as follows: applied voltage: 5-9 kV, frequency: 1-3 kHz, helium (He) gas flow: 1-1.5 L/min, and plasma irradiation time: 1-300 sec. The experiment was conducted by preparing a culture medium containing mouse fibroblasts (NIH3T3) on a culture dish. A culture dish irradiated with plasma was introduced into a $CO_2$-incubator. The small animals used in the experiment involving plasma irradiation into living tissue were rat, rabbit, and pick and are deeply anesthetized with the gas anesthesia. According to the dependency of cell numbers against the plasma irradiation time, when only He gas was flowed, the growth of cells was inhibited as the floatation of cells caused by gas agitation inside the culture was promoted. On the other hand, there was no floatation of cells and healthy growth was observed when plasma was irradiated. Furthermore, in an experiment testing the effects of plasma irradiation on rats that were artificially given burn wounds, no evidence of electric shock injuries was found in the irradiated areas. In fact, the observed evidence of healing and improvements of the burn wounds suggested the presence of healing effects due to the growth factors in the tissues. Therefore, it appears that the interaction due to ion/radicalcollisions causes a substantial effect on the proliferation of growth factors such as epidermal growth factor (EGF), nerve growth factor (NGF), and transforming growth factor (TGF) that are present in the cells.

• Journal of the Korean Society of Safety
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• v.22 no.4
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• pp.20-25
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• 2007

Instrument transformers are a safe measurement device designed to measure high voltage and large current. A current transformer(CT) is a type of instrument transformer designed to provide a current in its secondary winding proportional to the current flowing in its primary. It is commonly used in metering and protective relaying in the electrical power industry where it facilitates the safe measurement of large current. But, care must be taken that the secondary of a current transformer is not disconnected from its load while current is flowing in the primary, as this will produce a dangerously high voltage across the open secondary, and may permanently affect the accuracy of the transformer. Especially, industrial disaster such as an electric shock and/or a burn accident occurs occasionally by disregard of warning or attention. In this paper, we developed the detector for open of current transformer secondary terminal, and which was tested by the Korea Electrotechnology Research Institute. Test results show that Current Transformer secondary Open Detector(CTOD) interrupted within one second electronically when the 2nd terminal of current transformer opened.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.1088-1090
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• 2001

In general, Power SCR(Silicon Controlled Rectifier) is most widely used in Power Plant as well as Industrial field. It has been controlled and operated according to its own control method. Especially, in case of Power plant, it plays a major role in AVR(Automatic Voltage Regulator) or electro chlorination control circuits. Generally, they used in Analog control system at above field. But each SCR current value is different because of load unbalance or switching characteristic variations, it may cause power plant unit trip or system disorder according to SCR element burn out or bad operating condition. Therefore, in this paper a development of 3 phase current balance control unit is described, it gets over the past analog control system limit, uses DSP(Digital signal processor) had high speed response, controls SCR gate firing angle for 3 phase current balance.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.4
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• pp.11-18
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• 2016

Today, wearable technology products are used in a wide range of consumer, healthcare, bio-medical, and industrial applications. The market for wearable technology products is expected to increase dramatically over the next several years. In addition, concerns for safety, performance and reliability of wearable products keep increasing and will be essential for widespread acceptance in the marketplace. Wearable smart devices, which are generally in contact with the human body and skin, are exposed to the risk of the electric shock, burn, and explosion. Therefore, the standardization of wearable devices in terms of human safety and reliability should be very important. Furthermore, the development of test method and test certification of the wearable products will be one of the key technology for mass production. Such standardization and certification will help consumers to choose the safest and best quality wearable devices and allow manufacturers to prove the safety and quality of their products, thereby helping them to gain a competitive technology. This paper discusses the current status of the wearable smart devices as well as the standardization and test certification applicable to wearable technology products.