• Journal of ILASS-Korea
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• v.25 no.2
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• pp.81-88
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• 2020

Electrospray is used in various industries because it can produce continuous and uniform droplets. However, it is difficult to find optimal spraying condition due to lack of data in various conditions. In this study, various conditions were divided into electric parameters and fluid property. The electric parameters set Nozzle to Substrate(NTS), nozzle diameters and the fluid property set viscosity and conductivity as conditions. In this study, it observes spray patterns, Sauter Mean Diameter(SMD) according to conditions. As a result, fluid properties had a greater effect on the cone-Jet mode than on the nozzle diameter, NTS, and flowrate. All of solutions have Stable cone-jet mode at voltage of 8.5 kV, NTS of 20 mm and nozzle diameter of 0.2 mm. SMD has 27% different depending on viscosity and conductivity. The increased flowrate and viscosity are rising break-up length and thickening jet also jet is thinned by increased conductivity. Experiments have confirmed that the jet is thickened by increased flowrate and viscosity, and that the jet is thinned by conductivity.

• Fashion & Textile Research Journal
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• v.8 no.3
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• pp.363-369
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• 2006

In this the study, Lyocell fabrics for blanket were developed to get high value added goods for elder and Infant. Therefore, the purpose of the study was determine the effect of twist per inch on the physical properties of developed fabrics, including compression property and abrasion resistance on the process for making Lyocell combined yarns. For comparison, commonly used cotton blanket was used. The results were as the follows: 1) Dimensional changes of Lyocell fabrics was in -3% which value was pretty stable, and antistatic property was very good with 10V of electric propensity voltage which means there was no static electricity at all. Pilling property of Lyocell fabrics showed 3 grade which was good and air permeability and moisture vapor transmission rate of Lyocell fabrics were higher than those of cotton fabric and keeping warmth rate of Lyocell fabrics was about 50% which means it very warms. 2) Twist per inch of Lyocell combined yarns increased with tensile strength and elongation of Lyocell fabrics. 3) Twist per inch of Lyocell combined yarns increased with decreasing thickness reduction rate and therefore, compression property of those was pretty good. Specially, compression property of Lyocell fabrics made with yarns of 3.9TPI was better than those of cotton fabric. 4) Twist per inch of Lyocell combined yarns increased with abrasion resistance of Lyocell fabrics.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.102.2-102
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• 2003

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.158.1-158
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• 2002

• Proceedings of the Korean Magnestics Society Conference
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• 2016.05a
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• pp.159-159
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• 2016

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.76-79
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• 2000

The 3$\mu\textrm{m}$-thick PVDF (Polyvinyiidene fluoride) thin film have been prepared using physical vapor deposition with electric field, and its FT-IR specrum, dielectric property and electric conduction phenomenon have been investigated. Since the characteristic peaks ate detected at 509.45 and 1273.6〔cm〕 in the FT-IR spectrum, we are confirmed that the ${\beta}$ -phase is dominant in the PVDF thin film. In the results of dielectric properties, the PVDF thin film shows anomalous dispersion, i.e. gradual decrease of dielectric constant with increase of frequency, and also that the dielectric absorption point changes from 200Hz to 7000Hz with increasing temperature of thin film, which is consistent with the Debye's theory. The activation energy (ΔH) obtained from temperature dependence of dielectric loss is 21.64 ㎉/㏖. We confirm that the electric conduction mechanism of PVDF thin film is dominated by ionic conduction by investigating the dependence of the leakage current of the thin film on the temperature and the electric field.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.2
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• pp.235-241
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• 2001

A crack with electrically conducting surfaces in a linear electrostrictive ceramic subjected to uniform electric fields is analyzed. Complete forms of electric fields and elastic fields for the crack are derived by using the complex function theory. The linear electromechanical theory predicts overlapping of the traction free crack surfaces. It is shown that the surfaces of the crack are contact near the crack tip. The contact zone size obtained on the basis of the linear dielectric theory for the conducting crack does not depend on the electric fields and depends on only the original crack and the material property for the linear electrostrictive ceramic.

• 연구논문집
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• s.30
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• pp.93-99
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• 2000

Electro-Rheological(ER) fluids change their apparent viscosity according to the electric field strength. The electrical and rheological properties of zeolite based the ER fluids were reported. The electric field dependent yield stress are obtained from experimental investigation on the Bingham property of the ER fluid. Using ER fluids, it is possible to directly interface between electric drop and flow rate of the ER fluid was hydraulic control valve measured under application of an electric field. The purpose of the present study is pressure drop measurement of an ER valve by using strain gage. The performance characteristics of the valve system are evalusted in terms of pressrue fixed with respect to the intensity of employed electric fields and flow rates. As a result, it is esperimentally confirmed that pressure control valve using ER fluids applicable to use in hydraulic power systems.

• Korean Journal of Acupuncture
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• v.21 no.4
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• pp.1-19
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• 2004

Objectives : To understanding biological mechanism of acupuncture therapy, we have proposed a hypothesis. First of all, there exists electric property in meridian and meridian point. Second of all, energy flowing in meridian is related with electric property. Third of all, there is electronic interaction between the operator who performs acupuncture therapy and the receiver who is given acupuncture therapy. Forth of all, acupuncture effects may depend on the electric capacity which is transferred between the operator and the receiver via acupuncture needle. Methods : Under the hypothesis, we studied the effects of electric change in $ST_{37}(+)\;and\;ST_{39}(-)$ generated by Tanchim (彈鍼) manipulation which was stimulated at $ST_{36}$ point. And compared with data on the changes of electric change from the hand of the operator during acupuncture stimulation. Electric charge induced via acupuncture needle from the operator may be important factor that causes the changes of electric change in meridian and acupoint in the receiver. Therefore we investigated the changes of electric charge induced by the operator using Maclab 400 by the following methods. The one was in stable electric circle condition and the other was in unstable electric circle condition. Results : In this experiments, the changes of electric change from the stimulation type of Tanchim manipulation performed in our lab condition in acupuncture therapy was induced at least three factor, one was the difference of bio-potentials between the operator and the receiver of acupuncture therapy, another was the depth of acupuncture insertion from the skin of the receiver, the other was an electromyogram of the receiver. Conclusion : The data imply that the first factor should make a capacitance current when the operator touched the acupuncture needle which was inserted in the receiver. Therefore, the results suggest that capacitance currents stimulus in electronic view may be important factor in acupuncture therapy between the operator and the receiver of acupuncture therapy.

• Korean Journal of Acupuncture
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• v.22 no.4
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• pp.9-27
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• 2005

Objective : hypothesis. First of all, there exists electric property in meridian and meridian point. Second of all, energy flowing in meridian is related with electric property. Third of all, there is electronic interaction between the operator who performs acupuncture therapy and the receiver who is given acupuncture therapy. Forth of all, acupuncture effects may depend on the electric capacity which is transferred between the operator and the receiver via acupuncture needle. Methods : Under the hypothesis, I studied the effects of electric charge in ST37(+) and ST39(-) generated by Apchim (押鍼) manipulation which was stimulated at ST36 point. And compared with data on the changes of electric charge from the hand of the operator during acupuncture stimulation. Electric charge induced via acupuncture needle from the operator may be important factor that causes the changes of electric charge in meridian and acupoint in the receiver. Therefore we investigated the changes of electric charge induced by the operator using Maclab 400 by the following methods. The one was in stable electric circle condition and the other was in unstable electric circle condition. In this experiments, the changes of electric charge from the stimulation type of Apchim manipulation performed in our lab condition in acupuncture therapy was induced at least three factor, one was the difference of bio-potentials between the operator and the receiver of acupuncture therapy, another was the depth of acupuncture insertion from the skin of the receiver the other was an electromyogram of the receiver. Results :The data imply that the first factor should make a capacitance current when the operator touched the acupuncture needle which was inserted in the receiver. Therefore, the results suggest that capacitance currents stimulus in electronic view may be important factor in acupuncture therapy between the operator and the receiver of acupuncture therapy.