• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1480-1481
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• 2007

본 연구는 SF6를 대체하기 위한 건조공기(Dry-Air)의 특성을 연구할 목적으로 교류전압 인가 시 압력(P)변화 및 갭길이의 변화에 따른 절연파괴특성을 연구하였다. 본 연구를 통해 챔버 내의 P가 증가 할수록 절연파괴특성은 증가하는 것을 확인했다. 그리고 불평등전계 보다 평등전계에서 절연파괴특성이 더 증가하고 전극간거리(d)가 증가 할수록 절연파괴특성이 증가하는 것을 확인했다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.80-83
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• 2003

We have investigated the generation of pretilt angle for a nematic liquid crystal (NLC) alignment with in-situ photoalignment method on polyimide (PI) surfaces using thin plastic substrates. The LC aligning capabilities and pretilt angle of the thin plastic substrates by in-situ photoalignment method were better than that of the glass substrate by general photoalignment. Also, the LC pretilt angle increased with increasing healing temperature and exposure time.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.176-179
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• 2003

ITO films on PET substrate were prepared by DC magnetron sputtering method using powdery target with different deposition conditions. In addition, the electrical and optical properties were investigated. As the sputtering power and working pressure were higher, the resistvity of ITO films increased. The optical transmittance deteriorated with increasing sputtering power and thickness. As the working pressure increased, however, the optical transmittance improved at visible region of light. From these results, we could deposited ITO films with $8{\times}10^{-3}\;{\Omega}-cm$ of resistivity and 80% of transmittance at optimal conditions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.529-532
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• 2003

In this paper, the discharge characteristics of silent discharge chamber with 2mm and 3mm gap spacings were investigated. Dielectric of $Al_2O_3$ was embedded in the cylindrical type of discharge chamber. It was known that V-I and P-V characteristics depend strongly on the charge transportation characteristics, and in the low frequency silent discharge mode of operation, discharge voltage was always sustained to Vd, irrespective of applied voltage.

• 한국정밀공학회지
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• 제14권2호
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• pp.84-91
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• 1997

This paper reports the effort for developing this new Unified Manufacturing Instruction Set and its environment, called here UniSet, to deal with difficulties in set up and operation of Flexible Manufacturing Cells, UniSet has been developed as a non-exclusive unified manufacturing instruction set based on com- parisons of the prevailing machine tool and programming primitives. UniSet allows programmers to deal with only one instruction set, if they so desire, in a single coherent enviroment, rather than numerous machine programming languges. The software system is coded in an Object-Oriented Programming (OOP) language, Smalltalk, and derives its paradigm from the OO philosophy. Test results are also includ- ed to demonstrate the applicability of the approach employed.

• 대한치과기공학회지
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• 제7권1호
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• pp.19-25
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• 1985

In oder to compare and measure bond strength of ceramometal system with use of ceramco porcelain powder including SnO2 and uni metal, Rexillium III, Vera Bond as non precious alloys manufactured for porecelain-metal restorations. Total 24 test sample were constructed. All Test sample were measured with a Mitutoyo micrometer graduated to 0.01mm. It is as follows measured of thickness 3.3mm(metal : 1.1mm, porcelain: 2.2mm), width 12mm, length 30mm(porcelain 12mm x 12mm), Compared maximum bending stress test. The results obtained were as follows: 1. Bond strength of each metal with ceramco porcelain powder showed statistical significance.(P<0.05) 2. Vera Bond and uni metal, uni metal and Rexillium III revealed no statistical Significance.(P>0.05) Vera Bond and Rexillium III showed statistical significance.(P<0.05) 3. The order of maximum bending stress was Rexillium III, uni metal, vera Bond. The order of bond strength ratio making bending stress was Vera bond, uni metal, Rexillium III.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.200-202
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• 2006

We investigated the operating characteristics of a flux-lock type superconducting fault current limiters according to the number of the serial connection each the superconducting element at the additive polarity winding of a transformer. This SFCL consists of two coils wound in parallel on the same iron core, and the secondary coil is connected to the elements in series. Operating characteristics can be controlled by adjusting the inductances and the winding directions of the coils. It turns ratio between the primary and the secondary coils is 63:21. The analysis of voltage, current, and resistance in serial connection each element was performed to increase the applied voltage of flux-lock type SFCL. When the applied voltage was 200/$\sqrt{3}[V_{rms}]$ with three elements connected in seres, the peak value of the line current increased up to 26,24[A]. On the other hands, resistive SFCL increased up to 36.35[A], under the same conditions. This enabled the flux-lock type SFCL to be easy to increase the capacity of power system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1460-1462
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• 1994

BiCMOS is the newly developed technology that integrates both CMOS and bipolar structures on the same integrated circuit. Improved performance can be obtained from combining the advantages of high density and low power in CMOS with the speed and current capibility advantages by bipolar. However, the major drawbacks to BiCMOS are high cost, long fabrication time and difficulty of merging CMOS with bipolar without degrading of device Performance because CMOS and bipolar share same process step. In this paper, N-Well CMOS oriented BiCMOS process and optimization of device performance are studied when N-Well links CMOS with bipolar process step by 2D process and 3D Device simulation. From the simulation, Constriction of linking process step has been understood and provided to give the method of choosing BiCMOS for various analog design request.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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• pp.947-949
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• 1998

In this paper, the NO was oxidized $NO_2$ by using the non-thermal plasma and NOx removal characteristics were measured by showering NaOH water-solution to $NO_2$. The NO oxidation increased in the order of DC, AC, and Pulse. NOx oxidation for two stage with applied voltage was better than that for one stage with applied voltage. NO oxidation didn't depend on applied voltage. While NO oxidation was going on, NOx removal efficiency was 20-25%, however, significantly depended on the injection method of air and $H_2O$ + air. When NaOH water-solution density of 20% was showered to flue gases, NOx removal efficiency increased to 64%.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.143-146
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• 1999

A method to control the speed of DC motor with one-chip microprocessor PIC using PWM is discussed in this paper. This thesis deals with the DC motor speed control for electric bicycles which may be used as an alternative means of transformation in the future. We tried to design a stable system for controlling the speed of DC motor and materialized an electric bicycle loading this system. Now we are on the way to find out the problems this system has and work out the solutions.