• Title/Summary/Keyword: Resistance Method

Search Result 6,900, Processing Time 0.034 seconds

The fabrication of electrodes with low resistance and fine pattern for PDP

  • Cho, Soo-Je;Ryu, Byung-Gil;Park, Myung-Ho
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2000.01a
    • /
    • pp.107-108
    • /
    • 2000
  • We propose the method which is possible to fabricate the electrodes with the fine pattern and low resistance by photolithography and electroplating. The widths of pattern fabricated were 30, 50, 70 and 100um and the thickness could be up to $10{\mu}m$. The resistivity of the copper electrode electroplated was below $2.0{\mu}{\Omega}$ cm which is about half of photosensitive silver electrode. Dielectric layer was coated on the electrodes by screen printing and the pores harmful to the discharge were not formed after heat treatment. In the viewpoint of resistance and patterning, this method has much higher potential for large area display than other methods like screen printing, photosensitive conductive paste method and sputtering.

  • PDF

Measurement of Resistance of Multi-Grounded System by Ground Current Measurement (접지전류 측정에 의한 다중 접지계통의 접지저항 측정)

  • 최종기;안용호;정길조;한병성;김경철
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.53 no.4
    • /
    • pp.234-237
    • /
    • 2004
  • Measuring ground resistance has been a popular method of evaluation of the grounding electrode performance. If some portions of grounding electrodes are lost by corrosion, aging or other reasons, consequent deteriotation of the grounding performance would be resulted. It is one of the reasons why it is required to evaluate the performance of grounding systems regularly. However, in case of the electric facilities with multi-grounded system such as power substations with multi-grounded overhead ground wires and/or distribution line neutrals, it is practically difficult to disconnect neutrals or skywires from the substation grounding mesh for the ground resistance measurement. In this paper, a method for the grounding performance measurement of multi-grounded systems, which is based on the measuring ground current distributions, has been proposed. A field test results has shown the validity of the proposed test method.

Speed Sensorless Control of Induction Motors in the Very Low Speed Region Considering the Secondary Resistance Identification using Flux Signal (자속정보를 이용한 2차저항 동정기능을 갖는 유도전동기의 저속영역 속도센서리스 제어)

  • Lee, Z.G.;Jeong, S.K.
    • Proceedings of the KIEE Conference
    • /
    • 2001.04a
    • /
    • pp.308-310
    • /
    • 2001
  • This paper investigates a novel speed sensorless control method of I.M considering the secondary resistance identification based on the transientless torque control technique. Especially, this paper aimed at the identification of the secondary resistance simultaneously with speed estimation superposing of sinusoidal flux wave to a constant flux value. Furthermore, the secondary flux with some frequency is controlled independently on torque control. The proposed speed estimation method is derived from a motor circuit equation theoretically and also it can be conducted easily by detecting primary motor currents and primary voltage commands at every sampling time. Some numerical simulations with the assumption of using a pulse width modulation(PWM) voltage source inverter are performed to verify the proposed method.

  • PDF

Hull Form Development for an AFRAMAX Tanker with a Composite Stern Frameline Concept

  • Kim, Ho-chung;Lee, Chun-ju;Kim, Su-hyung
    • Selected Papers of The Society of Naval Architects of Korea
    • /
    • v.1 no.1
    • /
    • pp.65-75
    • /
    • 1993
  • Hull form development for an AFRAMAX tanker characterized by the form parameters of $C_B\simeq0.8$, $L/B\simeq5.5$, $B/T\simeq3.5$, han been carried out by the application of ‘Composite Stern Frameline Concept’. The viscous resistance of the new form was much smaller than that of the conventional form. Form factor of the new form was only 0.18 compared to 0.30 for the conventional hull form, Nevertheless the propulsive efficiency was slightly lower and thus the required propulsion power was smaller by 5~6% at both full load and ballast condition. In addition, it is confirmed that introduction of the form factor method such as ITTC’78 method is highly advisable because there is a great risk of the underperdicting full scale resistance of the hull form whose form the extrapolation of moel resistance to full scale is to be based on Froude method with the correlation allowances usually applied to conventional hull forms.

  • PDF

Corrosion resistance of double Al-Mg coating films on steel sheet prepared by PVD method (PVD법에 의해 제작된 Al-Mg 이층 코팅막의 내식특성)

  • Im, Gyeong-Min;Lee, Seul-Gi;Jeong, Jae-In;Yang, Ji-Hun;Lee, Myeong-Hun
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2013.05a
    • /
    • pp.150-150
    • /
    • 2013
  • Al-Mg films were prepared onto steel sheet according to deposition condition by eco-friendly electron beam vacuum evaporation method. The influence of Al-Mg films on corrosion resistance was evaluated by salt spray test and electrochemical method etc.. From the experimented results, it was found that the Al-Mg films which showed good corrosion resistance tend to have fine structure with homogenious composition distribution. In addition, it was shown that the property of coating films can be improve by controlling thickness ratio and uniform distribution of intermetallic compounds in Al-Mg films.

  • PDF

Image Reconstruction of Subspace Object Using Electrical Resistance Tomography

  • Boo Chang-Jin;Kim Ho-Chan;Kang Min-Jae
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.6 no.1
    • /
    • pp.47-51
    • /
    • 2006
  • Electrical resistance tomograpy (ERT) maps resistivity values of the soil subsurface and characterizes buried objects. The characterization includes location, size, and resistivity of buried objects. In this paper, truncated least squares (TLS) is presented for the solution of the ERT image reconstruction. Results of numerical experiments in ERT solved by the TLS approach is presented and compared to that obtained by the Gauss-Newton method.

The Development of Hull form for Turtle Boat Type Incinerating Vessel Considering the Resistance Performance (저항 성능을 고려한 거북선 형상의 해상소각선 선형개발)

  • Lee, Kwi-Joo;Kwon, Kyu-Hyok;Lee, Kon-Chol
    • Journal of Ocean Engineering and Technology
    • /
    • v.13 no.2 s.32
    • /
    • pp.168-175
    • /
    • 1999
  • In the present paper, a hull form for the turtle boat type incinerating vessel was developed based on the Finite source Distribution Method(FDM) and 1-$C_p$ method. In order to obtain proper hull form within the limited time and budget, a computer program OCL(Optimization of $C_p$ and LCB) was developed adn used. For the confirmation of the theoretical results by OCL, these theoretical results were compared with results of model test in the circulating water channel (CWC)in Chosun University.

  • PDF

Measurement of Resistance of Multi-Grounded System by Ground Current Measurement (접지전류 측정에 의한 다중 접지계통의 접지저항 측정)

  • 최종기;안용호;정길조;한병성;김경철
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.53 no.4
    • /
    • pp.234-234
    • /
    • 2004
  • Measuring ground resistance has been a popular method of evaluation of the grounding electrode performance. If some portions of grounding electrodes are lost by corrosion, aging or other reasons, consequent deteriotation of the grounding performance would be resulted. It is one of the reasons why it is required to evaluate the performance of grounding systems regularly. However, in case of the electric facilities with multi-grounded system such as power substations with multi-grounded overhead ground wires and/or distribution line neutrals, it is practically difficult to disconnect neutrals or skywires from the substation grounding mesh for the ground resistance measurement. In this paper, a method for the grounding performance measurement of multi-grounded systems, which is based on the measuring ground current distributions, has been proposed. A field test results has shown the validity of the proposed test method.

Speed Sensorless Control of Induction Motors in the Very Low Speed Region Considering the Secondary Resistance Identification (2차 저항 동정을 고려한 유도전동기의 저속영역 속도센서리스 제어)

  • Hwang, D.I.;Jeong, S.K.
    • Proceedings of the KIEE Conference
    • /
    • 2000.07b
    • /
    • pp.1042-1045
    • /
    • 2000
  • Speed control without speed sensor is expected strongly to progress reliability, simplicity and cost performance of I.M and to expand its application part. This paper investigates a novel speed estimation method of I.M considering the secondary resistance identification based on the transientless torque control technique. Especially, this paper aimed at the identification of the secondary resistance simultaneously with speed estimation. For this, the secondary flux with some frequency is controlled independently on torque. The proposed speed estimation method is derived from a motor circuit equation theoretically and also it can be conducted easily by detecting primary motor currents and primary voltage commands at every sampling time. Some numerical simulations with the assumption of using a pulse width modulation(PWM) voltage source inverter and experimental results are performed to verify the proposed method.

  • PDF

Evaluation of Fire Performance for High Strength Concrete Mock-up Column with Fiber by Unloaded Fire Test (비재하 내화시험에 의한 섬유혼입 고강도 콘크리트 Mock-up 기둥의 내화성능 평가)

  • Song, Young-Chan;Kim, Yong-Ro;Kim, Ook-Jong;Lee, Do-Bum
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2009.11a
    • /
    • pp.97-100
    • /
    • 2009
  • Fire resistance properties and mechanical properties of high strength concrete mock-up column using organic fiber by KS F 2257 Methods of fire resistance test for elements of building construction and compression test was investigated for application of precast concrete column method of high rise building in this study. As a test result, it was appeared that ECC permanent form is available as fire resistance method of high strength concrete and new precast concrete construction method for facilitating construction of high rise building.

  • PDF