• Title/Summary/Keyword: Electrode Size

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Effect of Ceramic-Electrode Interface on the Electrical Properties of Multilayer Ceramic Actuators (적층형 세라믹 액츄에이터의 세라믹-전극간 계면이 전기적 특성에 미치는 영향에 대한 연구)

  • 하문수;정순종;송재성;이재신
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.10
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    • pp.896-901
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    • 2002
  • The polarization and strain behavior of multilayer ceramic actuators fabricated by tape casting using a PNN-PZT ceramics were investigated in association with electrode size and internal layer number. Spontaneous polarization and strain decreased with increasing electrode size. In addition, the increase of internal layer number brought reduced spontaneous polarization and increased the field-induced strain. Because the actuators structure is designed to stack ceramic layer and electrode layer alternatively, the ceramic-electrode interfaces may act as a resistance to motion of domain wall. To analyze the effect of ceramic-electrode interface, the diffraction intensity ratio of (002) to (200) planes was calculated from X-ray diffraction patterns of samples subjected to a voltage of 200 V. The diffraction intensity ratio of (002) to (200) planes was decreased with increasing electrode size and internal layer number. The diffraction intensity ratio and straining behavior analyses indicate that the Polarization and strain were affected by the amount of 90°domain decreasing with increasing electrode size and internal layer number. Consequently, the change of polarization and displacement with respect to electrode size and layer number is likely to be caused by readiness of the domain wall movement around the interface.

Influence on Metal Removal Rate by Material and Size Difference of the Electrode (전극의 재료와 크기가 방전가공량에 미치는 영향)

  • 김희중
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.6
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    • pp.809-815
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    • 1998
  • This study has been performed to investigate MRR(metal removal rate) surface roughness with various pulse-on duration using the copper and graphite electrode according to the electrode size on the heat treated STD 11 which is extensively used for metallic molding steel in the EDM. The results obtained are as follow ;a)MRR increases a lot when pulse-on duration is 100 $\mu{s}$ or less but MRR has little difference with pulse-on duration of 100 $\mu{s}$ or more b) According to the increase of Pulse-on duration the large the electrode size the more MRR c) Safe discharge is needed to make maximum of MRR and the metallic organization must be complicated for discharge induction. d) Actual machining time is longer than theoretical machining time at the short pulse-on duration because of skin effect of current. e) Graphite electrode needs the larger electric discharge energy than copper electrode to remove remained chips completely.

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The Effect of Electrode Size during tDCS on Hand Function (경두개직류자극 시 전극 크기가 손기능에 미치는 영향)

  • Lee, Hye-Jin;Park, Soo-Ji;Kwon, Hye-Min;Lee, Jeong-Woo
    • Journal of the Korean Academy of Clinical Electrophysiology
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    • v.10 no.2
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    • pp.37-42
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    • 2012
  • Purpose : This study is to examine the effect of electrode size during transcranial direct current stimulation on hand function. Methods : By randomly assigning 26 right hand dominant subjects to two groups (I: carbon rubber electrode / II: disposable circular self-adhesive electrodes) with 13 subjects in each group depending on the electrode size, a positive electrodeof transcranial direct current stimulation was placed on the primary motor area (C4) and a negative electrode was placed on the left primary motor area (C3) and the stimulation was applied for 20 minutes.Hand function assessment before and after transcranial direct current stimulation were measured with JTT (Jebsen-Taylor hand function test). Results : According to hand function assessment by JTT, there were no interactions on both hands, and statistically significant differences according to time appeared in the main effect test. Conclusion : Regardless of the electrode size, it appears that transcranial direct current stimulation on the primary motor area activated hand function affected.

Influence on Relative Electrode Wear by Material and Size of Electrode (전극의 재료와 크기가 전극소모에 미치는 영향)

  • 전언찬
    • Journal of Advanced Marine Engineering and Technology
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    • v.23 no.5
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    • pp.671-677
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    • 1999
  • This study has been performed to investigate REW(relative electrode wear) in condition of vari-ous pulse-on duration using the copper and graphite electrode with change of the electrode size on the heat treated STD11 which is extensively used for metallic molding steel with the EDM. The results obtained are as follows; a) Graphite has much benefits than copper electrode when rapid machining is done without electrode wear, b) Neative REW result from the electrode that is very liable attach to decomposition carbide c)Increasing of machining time cause to increase wear length of the copper electrode and decrease wear length of the graphite electorde d)The more pulse-on duration copper electrode has the less REW. e) The edge portion of the electorde wears remarkably at the beginning of machining,.

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Study on Surface Plasmon Electrode Using Metal Nano-Structure for Maximizing Sterilization of Dielectric Discharge (유전체 방전 살균 극대화를 위한 금속 나노 구조를 이용한 표면 플라즈몬 전극에 관한 연구)

  • Ki, Hyun-Chul;Oh, Byeong-Yun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.31 no.2
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    • pp.80-84
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    • 2018
  • In this study, we investigated plasmon effects to maximize the sterilization of dielectric discharge. We predicted the effect using the finite difference time domain (FDTD) method as a function of electrode shape, size, and period. The structure of the electrode was designed with a thickness of 100 nm of silver nanoparticles on a glass substrate, and was varied according to the shape, size, and period of the electrode hole. Based on the results, it was confirmed that the effect of plasmons was independent of the shape of the electrode hole. It was thus confirmed that the plasmon effect depended only on the size and period of the holes. Further, the plasmon effect was affected by the size rather than period of the holes. Because the absorption of light by the metal varied according to the size of the hole, the plasmon effect generated by the absorption of light also varied. The best results were obtained when the radius and period of the electrode holes were $0.1{\mu}m$ and $0.4{\mu}m$, respectively.

Partial Discharge Characteristics of Ultra-High Voltage Cable Insulators by Needle Electrode (침 전극에 의한 초고압 케이블 절연재료의 부분방전 특성)

  • Kim, Gyun-Sig;Choi, Beom-Kyu;Byun, Doo-Gyoon;Cho, Kyung-Soon;Kim, Gwi-Yeol;Lee, Chung-Ho;Hong, Jin-Woong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07a
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    • pp.477-480
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    • 2004
  • In other to estimate an electrical properties of the cross linked polyethylene cable, the partial discharge properties due to charge of electrode shape(needle and bar) and void size were investigated at room temperature. Fast trip and breakdown time were appeared by the closed of needle electrode. The trip and breakdown voltage depend on insulator thickness. As the result, confirmed larger effect of void size than effect of insulator thickness. The effect of voids size than influence of insulation thickness was dominated by internal an electrode of inner insulators.

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Electrical Characteristics of SMD Type Ceramic Resonators using PbTiO3 System as a Function of Electrode Radius Size (전극직경 크기에 따른 SMD형 PbTiO3계 세라믹 공진자의 전기적 특성)

  • 민석규;류주현
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.8
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    • pp.671-677
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    • 2002
  • In this study, the high frequency SMD ceramic resonators with the size of $3.7{\times}3.1{\times}0.385\textrm{mm}^3$ were fabricated using $Pb_{0.88}(La_{0.6}Nd_{0.4})_{0.08}(Mn_{1/3}Sb_{2/3})_{0.02}Ti_{0.98}O_3$ ceramics with the variations of electrode radius size. With increasing the electrode radius size, resonant resistance in third overtone mode was decreased and electromechanical coupling factor($k_{t3}$) in third overtone mode was showed constant values. Taking into consideration mechanical quality factor($Qm_{t3}$) of 5,552 and dynamic range(D.R) of 60.72dB in third overtone mode, the ceramic resonator with the electrode radius size of $\theta$1.13mm was suitable for 20MHz resonator application.

Soldering characteristics of Ag-Pd electrodes in relationship to differing particle size of LTCC substrate (LTCC 기판의 Particle Size 에 따른 Ag-Pd 전극의 Soldering 특성 변화)

  • 조현민;유명재;박종철
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2002.05a
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    • pp.130-133
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    • 2002
  • Solder leaching resistance of the metal electrode is an important factor with regard to adhesion properties of ceramic substrate. In the Low Temperature Co-fired Ceramics (LTCC), Ag-Pd or Ag-Pt pastes are used instead of pure Ag paste to prevent leaching. Solder leaching behavior of the Ag-Pd paste in relation to LTCC raw material powder size was investigated. First fabrication of LTCC green tape with different particle size was done. LTCC substrates with Ag-Pd electrode were prepared using conventional multilayer ceramic process. Dipping test was performed to test solder leaching behavior of the electrode. Ag-Pd electrode on LTCC substrate with smaller particle size achieved higher solder leaching resistance.

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Study on Bubble Generation and Size by Dimensionally Stable Anode in Electroflotation Process (전기부상공정에서 촉매성 산화물 전극에 따른 기포 발생량과 크기에 관한 연구)

  • Kim, Dong-Seog;Park, Young-Seek
    • Journal of Environmental Science International
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    • v.16 no.10
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    • pp.1189-1195
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    • 2007
  • Small gas bubbles are used in many environmental and industrial processes for solid-liquid separations or to facilitate heat and mass transfer between phases. This study examines some of the factors that affect the bubble volume and size processed in the EF (electroflotation) process. The effect of electrode material, NaCl dosage, current and electrode distance were studied. The results showed that the generated bubble volume with electrode material lay in: Pt/Ti ${\fallingdotseq}$ Ru/Ti ${\fallingdotseq}$ Ir/Ti > Ti electrode. The more NaCl dosage was high, the smaller bubble was generated due to the low electric power. Bubble generation was increased with increase of current. With the increase of NaCl dosage, bubble generation was increased at same electric power (16.2 W). Generated bubble volume was not affected by electrode distance. However, no clear trends in bubble size as a function of these parameters were evident.

The Effect of particle size and ratio of LSM-YSZ powders on SOFC cathod properties (LSM과 YSZ의 분말크기 및 분말크기비가 SOFC의 양극특성에 미치는 영향)

  • 김재동;김구대;박지애
    • Journal of the Korean Ceramic Society
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    • v.37 no.3
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    • pp.227-232
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    • 2000
  • The LSM-YSZ composite electrode as a mixture of LSM and YSZ shows percolation characteristics. It was identified that the polarization resistance of LSM-YSZ composite electrode depend on YSZ connectivity by changing powder size ratio of the DLSM/DYSZ. That is, YSZ in composite electrode showed low electrochemical activity without YSZ connectivity. However, the polarization resistance decreased abruptly with YSZ connectivity due to high electrochemical activity of YSZ in composite electrode. Because the amount of three phase boundary is dependent on LSM and YSZ particle size, the polarization resistance of cathode decreases as LSM and YSZ particle size decreases.

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