• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
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• pp.15-17
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• 2005

In this study, tunable dielectric materials are important for resonator, variable capacitor, phased array antenna and other devices application. In this paper, Dielectric constant increased and tuning range increased with the increased of $BaSrTiO_3/Li_{2}CO_{3}$ content, which probably can be explained by the substitution of Ba3+, Li1+ on BaTiO3 lattice. The tunability and dielectric loss of the $BaSrTiO_2/Li_{2}CO_{3}$ thick film, sintered at $1150^{\circ}C$, were about 43 % and 0.234 at 10$\sim$15 MHz, respectively. In case of BaSrTi/MgO, Dielectric constant decreased and tenability increased with the added of $BaSrTiO_3/MgO$. The ferroelectrics properties were distinct when adding Li to BST ceramic thick film, and paraelectrics pattern was distinct when adding Mg.

• 마이크로전자및패키징학회지
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• 제23권2호
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• pp.11-18
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• 2016

This study focused on examining the possibility for recycling of Fe-Si electric sheet. We manufactured Fe-6.5Si mother alloy using by Fe-Si electric sheet scrap for transformer core materials. And then, soft magnetic alloy powder which diameter and shape were $45{\sim}150{\mu}m$ and sphere type was prepared by gas atomization process. As we compared to commercial Fe-6.5Si powder, its diameter distribution and microstructure of recycled powder was a similar. To investigate the possibility of reusing the soft magnetic composite sheet for electronics, recycled powder was treated to have a high aspect ratio (AR), and we finally obtained the 65~66 AR and $2.3{\mu}m$ thickness powder. To release the residual stress of powder, heat treatment was conducted under $300{\sim}400^{\circ}C$, $N_2$ gas. And then, soft magnetic sheet was made by tape casting process using by those powders. After the density and permeability of tape was measured, and we confirmed that the recycled Fe-Si electric sheet scrap was possible to reuse the soft magnetic materials of electronics.

• 한국전기전자재료학회논문지
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• 제28권5호
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• pp.344-349
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• 2015

A new information society of late has arrived by the rapid development of various information & communications technologies. Accordingly, mobile devices which are light and thin, easy and convenient to carry on the market. Also, the requirements for the larger television sets such as fast response speed, low-cost electric power, wider visual angle display are sufficiently satisfied. The currently most widely studied display material, the Organic Light-emitting Diodes(OLEDs) overwhelms the Liquid Crystal Display(LCD), the main occupier of the market. This new material features a response speed of more than a thousand times faster, no need of backlight, a low driving voltage, and no limit of view angle. And the OLEDs has high luminance efficiency and excellent durability and environment resistance, quite different from the inorganic LED light source. The OLEDs with simple device structure and easy produce can be manufactured in various shapes such as a point light source, a linear light source, a surface light source. This will surely dominate the market for the next generation lighting and display device. The new display utilizes not the glass substrate but the plastic one, resulting in the thin and flexible substrate that can be curved and flattened out as needed. In this paper, OLEDs device was produced by changing thickness of Teflon-AF of hole injection material layer. And as for the electrical properties, the four layer device of ITO/TPD/$Alq_3$/BCP/LiF/Al and the five layer device of ITO/Teflon AF/TPD/$Alq_3$/BCP/Lif/Al were studied experimentally.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 II
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• pp.771-774
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• 2003

Passivation Ledge's device is taken possession on one-side to the Emitter in this Paper. contact used in this paper Pt as Passivation Ledge of device to use Schottky Diode which has leitmotif, It is accomplished Current Modulation that we wish to do purpose using this device. Space Charge acts as single device which is becoming Passivation to know this phenomenon. This device becomes floating as well as Punched-through. V$_{L}$ (Voltage for Ledge) = - 0.5V ~ 0.5V variable values , PD(Partially Depleted ; Λ＞0), as seeing FD(Fully Depleted ; A = 0) maximum electric current gains and Gummel Plot of I-V characteristics (V$_{L}$ = 0.1/ V$_{L}$ = -0.1 ). Becomming Degradation under more than V$_{L}$ = 0.1 , less than V$_{L}$ =-0.05 and Maximum Gain(=98.617076 A/A) value in the condition V$_{L}$ = 0.1. A Change of Modulation is electric current gains by using Schottky Diode and Extrinsic Base PN Diode of Passivation Ledge to Emitter Depletion Layer in HBT of Gummel-Poon I-V characteristics and the RF wide-band electric current gains change the Modulation of CE(Common-Emitter) amplifier description, and it had accomplished Current Gain Modulation by Ledge Bias that change in high frequency and wide bands. wide bands.s.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.169-171
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• 2006

Nowadays, inverter welding is risen in spot welding, because can secure productivity. This study made changed output wave form of inverter welding equipment by several forms and measured electric current that pass to the second of transformer for welding. Purpose of study is finding electric current of most suitable form. Also, studied applies PID control in electric current control of inverter resistance weld device and heightens electric current precision.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 D
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• pp.751-753
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• 1997

The field test system covers three substation, 25 distribution feeders and 125 automated switches. Many small electric vendors participated in this project. Although each device is a small prototype, it was designed to carry out all of the functions. In performing the project, KEPRI has gained valuable experience, through dealing with many difficult problem. This paper is depicted about many kind of those difficult problems.

• 전기학회논문지P
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• 제66권4호
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• pp.182-187
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• 2017

Synchronous generators have been significantly applied in large-scale power plants and its monitoring systems are additionally established to sequentially observe states and outputs. We develop a computer based monitoring device for three-phase synchronous power generators in this paper. First, a test-bed of such generator system is created and then a interface board is constructed to transfer electric signals including the output voltage and the current from generators into a computer system via a data acquisition device. Its RMS(root-mean-square) values are continuously shown on a screen of computer systems and its time-histories graphs are additionally illustrated under a graphic user interface(GUI) mode. Lastly, we carry out real-time experiments using the generator system with the monitoring device to demonstrate its reliability and superiority by comparing results of a generic power analyzer which is well-used in measuring various power systems practically.

• 한국기계가공학회지
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• 제15권6호
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• pp.64-69
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• 2016

Vehicle clutch measurement for disc cushion variation was developed for the production of high quality Dual clutch transmissions. The developed device is composed of load cells for load measurement and LVDT for measuring the distance variation measurement in cushion variation. The servo motor-driven electric press for flexible loads that was developed was controlled by a PC-based HMI system, LabVIEW, and the device was able to continuously record real time measurement data with the accuracies of ${\pm}0.1\;kgf$ load and ${\pm}5{\mu}m$ cushion amount, which is far above the requirements of commercial vehicle standards.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.595-597
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• 2005

This paper shows the development of remote control system for manipulators which consists of PHANToM Device as a master, Samsung FARA robot as a slave and TCP/IP based LAN fortheir Communication. This work includes the motion mapping between the master and the slave, Generation of virtual viscosity force preventing operator's unwilled action and 3D remote control simulators for the stable operation of the remote control system, etc. The remote control implementation has been performed and the results shows that the developed system can allow the operator to effectively control the manipulator.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.538-541
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• 2007

In this paper, with a bistable curve of the bistable chiral splay nematic liquid crystal (BCSN LC) device, we clarify how the twist-to-splay transition is achieved under a horizontal field. By a sufficiently high horizontal electric field, the bistable property becomes monostable. The transition can be achieved.