• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.283-285
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• 1987

Transient conduction current (I - t characteristics) were measured in thin PPMMA (plasma-polymerized methyl methacrylate) films over the temperature range $60^{\circ}C-140^{\circ}C$ and the applied voltage range 3V - 30V. The current, which increased with temperature rise at constant applied voltage, showed less absorption current (current decay with time) at higher temperature region compared with those at lower temperature region. And the current, which increased with applied voltage rise at the constant temperature, showed less absorption current at higher voltage compared with those at lower voltage. The electric field current density characteristic curves were abtained from the conduction current values were after applying voltage for 30 minutes. And transient conduction currents were analyzed with high field conduction theories.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.3
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• pp.292-300
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• 1999

Fin conduction not only enhances heat transfer to the ambient air but also increases tube-to-tube conduction. The latter is known to deteriorate the heat exchanger performance. Heat conduction between neighboring tubes thorough the fin is numerically investigated for accurate performance analysis of plate finned-tube heat exchangers. Governing equations for arbitrary plate fin are solved and the temperature distribution is obtained using the principle of superposition. Analysis is made using finite element method by changing the shapes of fin, the arrangements of tubes and the fin parameter mD. It is found that tube-to-tube conduction is significant when mD is small or the distance between neighboring tubes is small.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1988.10a
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• pp.108-111
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• 1988

In this study, the electrical conduction properties of plasma-polymerized (MMA+Styrene) thin film have been investigated. The measurements of transient conduction currents were carried out in the temperature of 50 to 150$^{\circ}C$ at electric field of 10$^4$to 10$\^$6/V/cm. The electric field-current density characteristic curves were divided into three regions-ohmic region, child region, sudden-increasing region. It is shown that the conduction mechanism of this thin film is in good agreement with SCLC(space charge limited current) model by applying the high field conduction theories.

• Journal of the Korean Solar Energy Society
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• v.37 no.5
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• pp.77-84
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• 2017

The purpose of this paper is to propose the way of computing conduction time series factors (CTSF) using numerical method. After the accuracy of the numerical solution procedure being verified, the method is applied to the wall type 24 and roof type 14 of ASHARE to find the conduction time series coefficients, so called conduction time series factors. The results agree well with the values presented in the ASHRAE handbook. The method proposed can be easily applied to find unknown CTSF for more complex structures. It provides information about the temperature changes at a given location and time, thus validity of generated CTSF can be checked easily.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.6
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• pp.305-311
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• 2004

Charge transport phenomena of polyaniline-DBSA/High Impact Polystyrene (PAM-DBSA/HIPS) blends have been studied through an examination of electrical conduction. HIPS used host polymer in the blends and PANI-DBSA obey a space charge limited conduction mechanism and a ohmic conduction mechanism respectively. However, PANI-DBSA/HIPS blends do not obey any classical conduction mechanism. Analysis of conduction mechanism revealed that the charging current of PANI-DBSA/HIPS blends increased with the increase of PANI-DBSA content. This result migrlt be explained by the reduction in the distance between PANI-DBSA particles enabling the charge carriers to migrate from a chain to a neighboring chain via hopping or micro tunneling. It was also found that the charging current of PANI-DBSA/HIPS blends decreased as the temperature was elevated, which is of typical phenomena in metals. It is speculated that the charge transport in PANI-DBSA particle was somewhat constrained due to strong phonon scattering.

• Annals of Clinical Neurophysiology
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• v.9 no.2
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• pp.89-92
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• 2007

A 33-year-old women developed weakness in all limbs 3 days prior to admission. Motor examination showed decreased strength in all limbs, but sensory examination was normal. Deep tendon reflexes were areflexia. Electrophysiological examination showed conduction blocks with nearly normal conduction velocities and terminal latencies in motor nerves and normal amplitudes and velocities in sensory nerves. Her serum was positive for IgG antibodies to gangliosides GM1, GD1b, and galactocerebroside. Acute motor conduction block neuropathy may be another variant of Guillain-Barre syndrome.

• Journal of the Korean Vacuum Society
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• v.8 no.3A
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• pp.187-193
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• 1999

In this study, PVDF thin films which show the excellent piezoelectricity and pyroelectricity, are prepared by PVD (physical vapor deposition) method, and thir electrical conduction phenomena for analyses of the electrical conduction mechanism and TSC (Thermally Stimulated Current) for identification of the behavior of conductive carriers are investigated. As a result of FT-IR(Fourier Transform Infrared Spectroscopy) spectra, the crystalline phase transforms $\alpha$ type into $\beta$ type with increasing electric field. From XRD (X-Ray diffraction) analyses patterns, the degree of crystallinity increases from 49.8% to 67%, as the substrate temperature increases from $30^{\circ}C$ to $80^{\circ}C$. As a result of electrical conduction phenomena, the electrical conduction mechanism of PVDF thin films is identified as ionic conduction mechanism. From TSC analyses, there are three peaks as P1, P2, P3 with increasing temperature, and with increasing substrate temperature, the peak temperature of TSC increases and the peak intensity of TSC decreases.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06a
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• pp.1064-1069
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• 1994

In order to realize the function of human interface of telecommunications whose objective is to interchange useful information among persons, we developed a bone conduction telephone with which hearing impaired persons with conductive or noise-induced hearing loss and presbycusis can communicate with each other without any other additional devices such as hearing aids. The bone conduction telephone we developed has chatacteristics as follows : (i) a hearing impaired person and a normal hearing person can communicate by bone and air conduction hearings, respectively, using only this telephone set because, as its receiver, it uses a bone conduction vibrator with which we can realize such function with the voice coil and damper of a small speaker unit, the vibrating plate, etc., (ii) it has tone control function compensating hearing losses of hearing impaired persons according to their hearing loss/frequency chatacteristics. Using the tone control function together with a received volume control, it has the received volume range of 20dB in loudness rating; and (iii) it has the function of three emergency calls and a bell lamp as the visual display of a received call.

• Journal of the Semiconductor & Display Technology
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• v.17 no.4
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• pp.6-10
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• 2018

Organic light emitting devices have attracted the attention of many people because of their high potential for self-emission and flexible display devices. However, due to limitations in device efficiency and lifetime, partial commercialization is underway. In this paper, we have investigated the electrical conduction mechanism of the organic light emitting device by the temperature and the thickness of the light emitting layer through the current - voltage characteristics with respect to the conduction mechanism directly affecting the efficiency and lifetime of the organic light emitting device. Through the study, it was found that the conduction in the low electric field region is caused by the movement of the heat excited charge in the ohmic region and the tunneling of the electric charge due to the high electric field in the high electric field region.

• Progress in Superconductivity and Cryogenics
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• v.10 no.1
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• pp.62-66
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• 2008

The characteristic of the superconducting magnetic energy storage(SMES) system is faster response, longer life time, more economical, and environment friendly than other uninterruptible power supply(UPS) using battery. So, the SMES system can be used to develop methods for improving power quality where a short interruption of power could lead to a long and costly shutdown. Recently, cryogen free SMES has developed using BSCCO(Bismuth Strontium Calcium Copper Oxide) wire. We fabricated and tested the conduction cooling system for the 600 kJ class HTS SMES. The experiment was accomplished for the simulation coils. The simulation coils were made of aluminium, it is equivalent to thermal mass of 600 kJ HTS SMES coil. The coil is cooled with two GM coolers through the copper conduction bar. In this paper, we report that the test results of cool-down and heat loads characteristics of the simulation coils. The developed conduction cooling system adapted to 600 kJ HTS SMES system and cope with the unexpected sudden heat impact, too.