• Korean Journal of Clinical Laboratory Science
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• v.51 no.2
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• pp.198-204
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• 2019

Various treatments can be attempted in patients with intractable epilepsy, in whom the symptoms of seizures are not controlled by various drugs. On the other hand, in patients requiring a surgical method, a preoperative examination is needed to determine the portion of seizure site to be resected. Electrodes are inserted into the cerebral cortex for accurate lesion measurements and safe operation. The electrodes inserted in the cortex not only record the electroencephalography (EEG), but also allow various tests to confirm the function of the part. One of these methods is the evoked potential test. From January 2015 to December 2018, the trends of measured waveforms in were analyzed 70 patients. The somatosensory evoked potential (SSEP) recorded on the electrode inserted in the cerebral cortex can be searched for the pathway of the central sulcus to avoid the primary motor area and primary sensory area. In addition, using the middle latency auditory evoked potentials (MLAEP) and flash visual evoked potentials (FVEP), the functional cortex in the auditory cortex and the visual cortex were compared with the seizure focus point on the EEG to help determine the location of the ablation and minimize functional impairment after surgery.

• The korean journal of orthodontics
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• v.20 no.1
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• pp.47-59
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• 1990

Respiration is one of the most important functions which are carried out in stomatognathic system. When nasal orifice is obstructed or the resistance of upper airway is increased mouth breathing is initiated. Mouth breathing is regarded as an important etiologic factor of dentofacial anomalies. This experiment was performed to observe the influences of metabolic acidosis, tracheal resistance and vagotomy on mouth breathing. After rabbits were anesthetized with sodium pentobarbital, a pair of wire electrode was inserted into mylohyoid muscle, anterior belly of digastric muscle and dilator naris muscle to record EMG activity. Femoral vein and artery were cannulated for infusion of 0.3N HCl and collection of blood sample to determine the blood pH, and tracheal intubation was done to control airway resistance. Mouth breathing was induced by metabolic acidosis. Increase of the airway resistance through tracheal cannula intensified the activity of dilator naris, mylohyoid and digastric muscle. The higher the resistance, the larger the EMG amplitude. After bilateral vagotomy, respiratory volume and inspiatory time were increased and the activities of dilator naris, mylohyoid and digastric muscle were strengthened. It was concluded that the muscle activity related to mouth breathing was induced by metabolic acidosis and increase of tracheal tube resistance.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.147-147
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• 2015

The multilayer structure of the organic light emitting diode has merits of improving interfacial characteristics and helping carriers inject into emission layer and transport easier. There are many reports to control hole injection from anode electrode by using transition metal oxide as an anode buffer layer, such as V2O5, MoO3, NiO, and Fe3O4. In this study, we apply thin films of LiF which is usually inserted as a thin buffer layer between electron transport layer(ETL) and cathode, as an anode buffer layer to reduce the hole injection barrier height from ITO. The thickness of LiF as an anode buffer layer is tested from 0 nm to 1.0 nm. As shown in the figure 1 and 2, the luminous efficiency versus current density is improved by LiF anode buffer layer, and the threshold voltage is reduced when LiF buffer layer is increased up to 0.6 nm then the device does not work when LiF thickness is close to 1.0 nm As a result, we can confirm that the thin layer of LiF, about 0.6 nm, as an anode buffer reduces the hole injection barrier height from ITO, and this results the improved luminous efficiency. This study shows that LiF can be used as an anode buffer layer for improved hole injection as well as cathode buffer layer.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.5
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• pp.373-379
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• 2016

Low carbon steel is usually used as the outer panel with low base metal resistance compared to the inner reinforced panel made with high strength steel, which makes it difficult to form a robust nugget. To overcome welding problems of a dissimilar three-sheet combination made of SGACEN, DP980 and CP1180, a cover plate was inserted between the upper electrode and SGACEN. The quality of the nugget was analyzed by comparing the welding signals and cross sectional images under maximum heat input both with and without the cover plate. To analyze the mechanical of weld properties, a hardness test analysis was conducted. To enhance the reliability of experimental results, temperature distributions were obtained using a simulation program. The method of inserting a cover plate led to a change in the heat input, which induced a larger nugget size between SGACEN and DP980.

• Transactions of Materials Processing
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• v.26 no.3
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• pp.174-180
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• 2017

In this study, a new spot welding with electric resistance heated dies is suggested for the spot welding of non-ferrous metal plates for drawing and concurrent spot welding. This welding method involves two heating processes such as heating by conduction of electric resistance heated dies and heating by resistance between contacted surfaces of two plates by welding current induced to copper dies for the fusion of contacted metal. This welding process has welding variables such as current induced in heated and copper dies, the inner diameters of heated dies, and edge shape of the copper dies. Experimental conditions for each current should be established to get successful welding strength. The welding strength could reach to the desired value in industrial fields under the following conditions of contact diameters of heated dies in this case of overlapped aluminum5052 plates with 0.3-mm thickness: inner and outer diameters of 5.0 and 16mm, respectively; diameter of copper dies, 5.0mm; heating current, 6.8kA in heated steel dies; welding current, 8.6 kA in copper dies.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.97.1-97.1
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• 2018

본 연구는 초고온 열처리 과정에서 멀티레이어 투명전극 박막의 고내열성, 고신뢰성을 얻기 위해 보호층을 삽입한 연구이다. 먼저 보호층의 고내열 효과를 알아보기 위해 보호층을 삽입한 박막과 그렇지 않은 박막을 200, 300, 400, 500, $550^{\circ}C$로 각각 열처리하여 비교하였다. 보호층을 삽입하지 않은 박막은 $500^{\circ}C$에서 멀티레이어 박막이 응집하여 전기적 광학적 특성이 저하되었다. 반면, 보호층을 삽입한 박막은 $550^{\circ}C$에서도 투과율 (%T) 89.5% (at 550nm wavelength), 면저항 $3.5{\Omega}/sq$로 투명전극으로서 뛰어난 특성을 보였다. 또한 고신뢰성을 확인하기 위해 상대습도 85%, 온도 $85^{\circ}C$ 조건에서 120시간 동안 항온항습 테스트를 수행하였다. 보호층이 없는 투명전극의 박막은 산화가 일어나 전기적 광학적 특성이 저하 되었으나, 보호층을 삽입한 투명전극의 박막은 전기적 광학적 특성의 변화가 거의 없는 것으로 확인되어 본 멀티레이어 투명전극에서 보호층의 핵심적인 효과를 입증할 수 있었다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.6
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• pp.408-411
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• 2018

We fabricated highly flexible Mn-doped $SnO_2$ (MTO)/Ag/MTO/polydimethylsiloxane (PDMS)/MTO multilayer transparent conducting films. To reduce refractive-index mismatching of the MTO/Ag/MTO/polyethylene terephthalate (PET), index-matching layers were inserted between the oxide-metal-oxide-structured films and the PET substrate. The PDMS layer was deposited by spin-coating after adjusting the mixing ratio of PDMS and hexane. We investigated the effects of the index-matching layer on the color and reflectance differences with different PDMS dilution ratios. As the dilution ratio increased from 1:100 to 1:130, the color difference increased slightly, while the reflectance difference decreased from 0.62 to 0.32. The MTO/Ag/MTO/PDMS/MTO film showed a transmittance of 87.18~87.68% at 550 nm. The highest value of the Haacke figure of merit was $47.54{\times}10^{-3}{\Omega}^{-1}$ for the dilution ratio of 1:130.

• Journal of Sensor Science and Technology
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• v.22 no.5
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• pp.309-314
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• 2013

Glass micropipettes are widely used for drug injection in neurological studies. To enable these devices to monitor neural activity simultaneously with drug injection, an electrode such as Ag/AgCl must be located near or inserted into the glass micropipette to detect electrical signals in vivo. Here, we report carbon-nanotube-modified glass micropipettes (CNGs), which have excellent electrochemical properties such as low impedance and large electrochemical surface area suited for neural recording. In addition, using a standard pressure pump, CNGs can deliver drugs to the target region without bending. Because they are based on standard glass micropipettes, CNGs can readily be applied to traditional equipment, creating opportunities to monitor precisely the drug-injected area.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1408-1409
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• 2007

In this paper, we developed a hybrid simulation model of carbon laser ablation under the Ar plasmas consisted of fluid and particle methods. Three kinds of carbon particles, which are carbon atom, ion and electron emitted by laser ablation, are considered in the computation. In the present modeling, we adopt capacitively coupled plasma with ring electrode inserted in the space between the substrate and the target, graphite. This system may take an advantage of ${\mu}m$-sized droplets from the sheath electric field near the substrate. As a result, in Ar plasmas, carbon ion motions were suppressed by a strong electric field and were captured in Ar plasmas. Therefore, a low number density of carbon ions were deposited upon substrate. In addition, the plume motions in Ar gas atmosphere was also discussed.

• Progress in Medical Physics
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• v.27 no.4
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• pp.224-231
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• 2016

The usefulness of Gel Bolus phantom was investigated by comparing the temperature distribution characteristic of the agar phantom produced to investigate the dose distribution characteristic of radiofrequency hyperthermia device with that of the Gel Bolus phantom under conditions similar to those of an agar phantom that can continuously carry out temperature measurement. The temperatures of the agar phantom and the Gel Bolus phantom were raised to $36.5{\pm}3^{\circ}C$ and a temperature sensing was inserted at depths of 5, 10, and 15 cm from the phantom central axis. The temperature increase rate and the coefficient of determination were analyzed while applying output powers of 100 W and 150 W, respectively, at intervals of 1 min for 60 min under conditions where the indoor temperature was in the range $24.5{\sim}27.5^{\circ}C$, humidity was 35~40%, internal cooling temperature of the electrode was $20^{\circ}C$, size of the upper electrode was 250 mm, and the size of the lower electrode was 250 mm. The coefficients of determination of 150 W output power at the depth point of 5 cm from the central axis of the phantom were analyzed to be 0.9946 and 0.9926 in the agar and Gel Bolus phantoms, respectively; moreover, the temperature change equation of the agar and Gel Bolus phantoms with time can be expressed as follows in the state the phantom temperature is raised to $36^{\circ}C:Y(G)$ is equation of Gel Bolus phantoms (in 5 cm depth) applying output power of 150 W. Y(G)=0.157X+36. It can be seen that if the temperature is measured in this case, the Gel Bolus phantom value can be converted to the measured value of the agar phantom. As a result of comparing the temperature distribution characteristics of the agar phantom of a human-body-equivalent material with those of the Gel Bolus phantom that can be continuously used, the usefulness of Gel Bolus phantom was exhibited.