• Electrical & Electronic Materials
• /
• v.8 no.5
• /
• pp.601-605
• /
• 1995

This study was concerned, after the oxide films(50 [.angs.]) were grown in a furnace and the MOS capacitor fabricated, with experimental comparison and verification about the Interference Effect of Electronic Waves in the ultra thin oxide/silicon interface. The average error was about 0.8404[%] in n'gate/p-sub and about 0.2991[%] in p$^{+}$gate/p-sub. Therefore, it was predicted that the Interference Effect of Electronic Waves can overcome somewhat according to the gate polarity.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.34 no.7
• /
• pp.1175-1183
• /
• 2010

This study investigates the effect of polarity of oily soil on adhesion of oily and particulate soil to PET fabric in oily/particulate mixed soil systems. The potential energy of interaction between two particles was examined as a fundamental environment of adhesion of soil to fabrics. The ${\zeta}$-potential of ${\alpha}-Fe_2O_3$ particles was measured by a microelectrophoresis method, and the potential energy of interaction between two particles was calculated by using the Verwey-Overbeek theory. The ${\zeta}$-potential of particle and the potential energy of interaction between two particles was slightly influenced by the polarity and type of oily soil, but increased with the increased anionic surfactant concentration and amount of oily soil. The adhesion of oily soil to fabric increased with the additional amount of polarity of oily soil and decreased surfactant concentration that was relatively high at a temperature of $60^{\circ}C$ surfactants solution. The adhesion of ${\alpha}-Fe_2O_3$ particle to PET fabric decreased with an increased amount and polarity of oily soil and increased surfactant concentration Although some similarity exists, the general trend of the adhesion to fabric by particulate soil differ from oily soil.

• Journal of Digital Convergence
• /
• v.14 no.6
• /
• pp.177-186
• /
• 2016

This study aims to explore the effect of characteristics of eWOM(Word-of-mouth) on consumer attitude in SNS(Social Network Service). The characteristics of WOM were classified into characteristics of message (polarity, verifiability, consensus) and characteristics of SNS (social presence, interaction). Data of 554 samples were collected from the university students of SNS users. The key results showed that the polarity of the WOM has a strong positive effect on consumer's attitude, and the degree of verifiability and consensus has a moderating effect on the polarity-attitude relationship. On the contrary, characteristics of SNS such as social presence and interaction have a direct effect on consumer attitude and have no significant moderating effect on the polarity-attitude relationship. This study provides an academic enhancement in the research of the relationship between the characteristics of WOM and consumer's attitude in the SNS environment. Practical implications are also drawn from these findings.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.13 no.2
• /
• pp.89-93
• /
• 2014

Variable polarity (VP) arc welding is known as an effective solution for aluminum thanks to the cleaning effect, which means oxide removal, during the DCEP (direct current electrode positive) period. In this research, VP GTAW (gas tungsten arc welding) is adopted for lap joint fillet welding of 3mm thickness 5052 aluminum alloy. Various welding currents and DCEP duty cycles are applied as welding conditions with a fixed welding speed to investigate the influence of DCEP characteristics on weld bead formation. Results show a tendency of higher heat input for higher DCEP duty cycle, which result does not follow conventional arc theory because it is known that DCEN (DC electrode negative) polarity is more efficient for heat input than is DCEP. This phenomenonhas recently been reported by several VP-GTA researchers and is still controversial because the mechanism of oxide removal is not yet clear except for the previous, well-known idea of "ion bombardment", which cannot explain the situation. Finally, proper usage conditions for VP-GTAW are suggested; then, further, related theoretical topics in the field of cathode physics are brieflyintroduced.

• Earthquakes and Structures
• /
• v.24 no.1
• /
• pp.1-9
• /
• 2023

A model for calculating structure interacted mechanics is proposed. A structural interaction model and controller design based on tuned mass damping (TMD) was developed to control the induced vibration. A key point is to introduce a new analytical model to evaluate the properties of the TMD that recognizes the motion-dependent nonlinear response observed in the simulations. Aiming at the problem of increased current harmonics and low efficiency of permanent magnet synchronous motors for electric vehicles due to dead time effect, a dead time compensation method based on neural network filter and current polarity detection is proposed. Firstly, the DC components and the higher harmonic components of the motor currents are obtained by virtue of what the neural network filters and the extracted harmonic currents are adjusted to the required compensation voltages by virtue of what the neural network filters. Then, the extracted DC components are used for current polarity dead time compensation control to avert the false compensation when currents approach zero. The neural network filter method extracts the required compensation voltages from the speed component and the current polarity detection compensation method obtains the required compensation voltages by discriminating the current polarity. The combination of the two methods can more precisely compensate the dead time effect of the control system to improve the control performance. Furthermore, based on the relaxed method, the intelligent approach of stability criterion can be regulated appropriately and the artificial TMD was found to be effective in reducing cross-wind vibrations.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.6 no.1
• /
• pp.19-23
• /
• 2000

The increasing use of plastics in food packaging materials has led to the issue of food-packaging mutual interactions from residues in the plastics. Plastic films are commonly printed by using solvent-based ink to decorate the packaged food for consumer attention. However, the residual solvents can not be completely removed and they can migrate into the contained food which lead to undesirable off-flavors. Partitioning (Kp) of printing ink solvents was studied in two types of plastic films with different chemical structure and polarity. At $25^{\circ}C$, Kp of toluene is higher than that of isopropanol in PP, but isopropanol showed higher Kp value than toluene in EVOH. This showed that polarity had a significant effect on the partitioning of printing ink solvents into the plastic films. Printing solvents had a higher affinity to the polymer with similar polarity than it did to the different one.

• Korean Journal of Materials Research
• /
• v.25 no.7
• /
• pp.352-357
• /
• 2015

To research the characteristics of ITO film depending on a polarity of SiOC, specimens of ITO/SiOC/glass with metal-insulator-substrates (MIS) were prepared using a sputtering system. SiOC film with 17 sccm of oxygen flow rate became a non-polarity with low surface energy. The PL spectra of the ITO films deposited with various argon flow rates on SiOC film as non-polarity were found to lead to similar formations. However, the PL spectra of ITO deposited with various argon flow rates on SiOC with polarity were seen to have various features owing to the chemical reaction between ITO and the polar sites of SiOC. Most ITO/SiOC films non-linearly showed the Schottky contacts and current increased. But the ITO/SiOC film with a low current demonstrated an Ohmic contact.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1436-1437
• /
• 2007

This paper presents the experimental results of the dielectric characteristics with temperature changes under highly non-uniform electric field in $SF_6$ gas. The impulse preliminary breakdown developments were investigated by the measurement of predischarge current and breakdown voltage. As a result, the first stremer corona is initiated at the tip of needle electrode, and bridges the test gap. Also the first stremer corona onset and breakdown voltages the negative polarity was much higher than that in the positive polarity in same temperature. In addition, the varition of temperature have a little effect on the positive polarity. On the other hand, in some cases negative polarity corona onset and breakdown voltages increased with increasing a high temperature.

• Journal of the Korean Society of Safety
• /
• v.6 no.2
• /
• pp.15-20
• /
• 1991

In this paper, we have investigated the effect of organic additives and prestressed D C. voltage on the impulse tree initiation in low density polyethylene. The five klnds of organic compounds was selected for the purpose of inhibiting tree initiation and 10 wt % of each additive was mixed in low density polyethylene. The positive or negative impulse voltage was applied after prestressed D.C. voltage was applied in order to investigate the effect of the space charge influenced on tree initiation. The lengths of tree initiation in case of belng same polarity between prestressed D.C. voltage and impulse voltage were longer than those in case of being different polarity between prestressed D.C. voltage and impulse voltage. When the polarity prestressed D.C. voltage was the different plarity of impulse voltage, the length of tree initiation increased with increasing the prestressed D.C. voltage and decreasing the rest time Among the organic additives used in this paper, the m-cresol can be shown to be the most effective inhibiter to tree initiation.

• Journal of Welding and Joining
• /
• v.19 no.6
• /
• pp.622-629
• /
• 2001

The aim of this experiment is to establish the method that obtains symmetrically two nuggets in microresistance series spot welding. The sheets of austenite stainless steel STS304 applied to various electronic parts were experimented by the inverter welding power source of polarity controllable type and by the twin head for left and right electrode force to be controlled separately. The experimental results were obtained as follows : 1) When series spot welding was carried out by DC 1 pulse as welding current with same electrode force at left and right, the asymmetry of nuggets was resulted from the larger nugget of the (-) pole because of the Peltier effect. The dynamic resistance of weld spot at left and right was appeared differently according to the growth of nuggets. 2) When AC 1 cycle by welding power source of polarity controllable type was applied, the nuggets were almost symmetrically formed. 3) In a twin head, if the electrode force of (-) pole was larger than that of (+) pole, the diameters of two nuggets became to same. It was confirmed that the dynamic resistance of (-) pole was decreased to the same level as it of (+) pole. 4) Although the forces of left and right electrode were same, and only DC 1 pulse was applied, symmetric nuggets were obtained if the conductivity of (+) pole was lower than it of (-) pole.