• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.4
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• pp.440-448
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• 1998

This paper considers the influence of circumferential wall heat conduction for the case of forced convection around a circular cylinder in cross flow of air. Keeping uniform heat generation from the inner surface of the cylinder in radial direction, heat is transferred by wall conduction in the circumferential direction due to the asymmetric nature of the temperature distribution of the cylinder and by convection around the perimeter of the cylinder. The wall conduction depends on conductivity of the cylinder and size of the cylinder radius and thickness and affects the local convective heat transfer rate significantly for geometrically similar surfaces and flow conditions. A nondimensional conjugation parameter K. (=k$_t$R/k$_w$b) has been used to characterize the effect of the circumferntial wall heat conduction. The small values of conjugation parameter K are found to be associated with large effect of wall conduction on the local convective heat transfer rate.

• Journal of Veterinary Clinics
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• v.21 no.2
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• pp.219-228
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• 2004

Heart diseases related to conduction system can be occurred by primary defects in conduction system and by secondary to morphological heart diseases or drug toxicities. Multiple molecular defects responsible for arrhythmogenesis, including mutations in ion channels, cytoplasmic ion-channel-interacting proteins, gap-junction proteins, transcription factors and a kinase subunit, were found to be associated with the aetiology of primary cardiac conduction defects, especially inherited form. Despite a big progress in unveiling human arrhythmogenesis, conduction defects in dog has not been well studied except sudden death syndrome in German shepherd. In this review, molecular genetics in cardiac arrhythmogenesis, inherited human diseases associated with conduction defects and similar diseases in dogs will be discussed.

• Elastomers and Composites
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• v.33 no.4
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• pp.246-254
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• 1998

In order to investigate the characteristics of resistance and conduction of vulcanized styrene butadiene rubber (SBR)/ carbon black (CB) composites, surface/ volume resistivity, point to point resistance, decay time, and electrical conduction experiments with four different kinds of non-conductive carbon black were measured. When about 50phr of carbon black were loaded in SBR, all resistivites suddenly decreased and critical region (Rc) was shown. Current densities of SBR/CB composites showed critical point (Pc) and increased with the electric fields. Electrical conduction mechanisms of SBR/CB composites could be considered as the ohmic conduction at low electric fields and the space charge limited conduction (SCLC) at high electric fields, respectively.

• Current Applied Physics
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• v.18 no.12
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• pp.1492-1495
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• 2018

This paper studies the influence of temperature on electrical resistivity in ${\alpha}-InAs$ thin films between 30 K-2K based on the analysis of Mott VRH model and ES VRH model. The effect of the interactions between electrons at lower temperature must be considered, therefore, ES VRH conduction will dominate mechanism, and the crossover from Mott to ES VRH conduction is observed about 7 K. Based on available experiment data and VRH conduction model, the parameters of VRH conduction are determined. And the calculated values of $T_C$ are consistent with the experimental results. In addition, $R_M/{\xi}$, ${\Delta}_M/kT$, $R_{ES}/{\xi}$ and ${\Delta}_{ES}/kT$ are satisfied with the validity of Mott and ES models. Furthermore, the temperature dependence of resistivity at low temperature obeys a universal scaling law, which well describes the overall temperature range of VRH conduction. However, the values of $T^{\prime}_M$ from the universal function are two order of magnitudes lower than $T_M$ deduced from fitting experiment.

• The Journal of Korean Physical Therapy
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• v.10 no.1
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• pp.199-212
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• 1998

The purpose of this article is to summary about the application of electromyography and nerve conduction study. Electrodiagnostic studies, which include nerve conduction studies, electromyography, repetitive nerve stimulation, single fiber EMG, late response tests and evoked potential tests are a critical component of the neuromuscular evaluation.

• Journal of Korean Physical Therapy Science
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• v.5 no.2
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• pp.603-616
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• 1998

The purpose of this article is to summary about the application of electromyography and nerve conduction study. Electrodiagnostic studies, which include nerve conduction studies, electromyography, repetitive nerve stimulation, single fiber EMG, late response tests and evoked potential tests are a critical component of the neuromuscular evaluation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.207-210
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• 1998

Electrical properties such as space charge distribution and electrical conduction of XLPE/VLDPE blends were studied. When the VLDPE is blended, residual charge inside XLPE increases. In case of electrical conduction characteristics, there were no changes in electrical conduction mechanism, space charge limited conduction. XLPE/VLDPE blend including crosslinking coagent showed relatively small current density. It might be due to the carbonyl group in crosslinking coagent.

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.167-170
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• 1999

In this paper, we operate Synchronous Reluctance Motor(SynRM) using the two-phase conduction method. Acually SynRM is operated by the sinusoidal PWM method but in home-appliance there is many restrictions of making the motor such as the method of winding, the shape of rotor etc. Therefore it is possible that there is little difference of performance between the two-phase conduction method and the sinusoidal PWM method. In this paper the characteristics of motor noise will be analyzed especially in the case of using the two-phase conduction method by experiment results.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.216-217
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• 2007

In this paper we investigated the volume resistivity and AC conduction current according to the temperature and voltage. As a result, the volume resistivity comes to be small according to the measurement temperature and voltage. AC conduction current of the heat treatment specimen is increased because of the decrease of insulation.

• Journal of the Korean Chemical Society
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• v.53 no.1
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• pp.42-50
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• 2009

The dielectric-spectroscopic and ac conductivity studies firstly carried out on layered manganese doped Sodium Lithium Trititanates ($Na_{1.9}Li_{0.1}Ti_3O_7$). The dependence of loss tangent (Tan$\delta$), relative permittivity ($\varepsilon_r$) and ac conductivity ($\sigma_{ac}$) in temperature range 373-723K and frequency range 100Hz-1MHz studied on doped derivatives. Various conduction mechanisms are involved during temperature range of study like electronic hopping conduction in lowest temperature region, for MSLT-1 and MSLT-2. The hindered interlayer ionic conduction exists with electronic hopping conduction for MSLT-3. The associated interlayer ionic conduction exists in mid temperature region for all doped derivatives. In highest temperature region modified interlayer ionic conduction along with the polaronic conduction, exist for MSLT-1, MSLT-2, and only modified interlayer ionic conduction for MSLT-3. The loss tangent (Tan$\delta$) in manganese-doped derivatives of layered $Na_{1.9}Li_{0.1}Ti_3O_7$ ceramic may be due to contribution of electric conduction, dipole orientation, and space charge polarization. The corresponding increase in the values of relative permittivity may be due to increase in number of dipoles in the interlayer space while the corresponding decrease in the values of relative permittivity may be due to the increase in the leakage current due to the higher doping.