• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.2
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• pp.70-77
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• 2007

The application of focused ion beam(FIB) technology has been broadened in the fabrication of nanoscale regime. The extended application of FIB is dependent on complicated reciprocal relation of operating parameters. It is necessary for successful and efficient modifications on the surface of silicon substrate. The primary effect by Gaussian beam intensity is significantly shown from various aperture size, accelerating voltage, and beam current. Also, the secondary effect of other process factors - dwell time, pixel interval, scan mode, and pattern size has affected to etching results. For the process analysis, influence of the secondary factors on FIB micromilling process is examined with respect to sputtering depth during the milling process in silicon material. The results are analyzed by the ratio of signal to noise obtained using design of experiment in each parameter.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.161-162
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• 2006

There are many alarms in Substation Automation System because of data types and quantities increasing, so it is very difficult for operators to know the actual situations. In order to help operators easily make decision, some unnecessary alarms should be removed or combined as one. In this paper, alarm processing is using the structure of substation system and the relation of measured data and events to make some rules. Conventional alarm processing just gives data, but proposed alarm processing gives the whole information. In a simulation model system, the data such as voltage, current and CB status are collected by HyperSim and saved in DB, then proposed alarm processing has been testified using those data based on real-time simulation.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.1039-1040
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• 2002

For the I-V modeling of sharp tip arrays and nanostructured planar emitters, we propose a new and much practical I-V relation including tip height and radius by considering a statistical distribution of tip radius. Frequently observed nonlinearity of Fowler-Nordheim plot for sharp tip and tip arrays was successfully simulated and then, an application example was provided to extract relevant emission-governing parameters of sharp tip.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.125-128
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• 1987

This paper deals with the topological observability analysis and the derivation of a reliability evaluation formula of a measurement system for state estimation. An analogy of the DC power flow method to the DC circuit analysis is introduced, and all the relationship between power flows and phase angles are replaced by the corresponding current-voltage relation. As a result, a set of topological measurement equation expressed in the form of the incidence matrix is derived for the topological analysis, and the observability test is carried out by examining the rank of the measurement matrix. The reliability evaluation formula was derived experimentally by testing the observability of sample systems of IEEE-14, IEEE-3.0, IEEE-57.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.2
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• pp.76-83
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• 2007

This report presents the test technique using optic thermal sensor for the HERO evaluation of equipment installed EED. The calibration method of EED-thermal sensor assembly is explained by relation between the current in bridge wire and voltage in thermal sensor. And the HERO test and evaluation method is indicated based on MIL-STD-464A and MIL-STD-331C. The safety and reliability levels of EED-thermal sensor assembly are evaluated when exposed in the electromagnetic environment.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.4
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• pp.711-716
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• 2011

This paper defines a generator reactive reserve considering power system network. Conventional generator reserve is calculated by the difference between the maximum reactive power output of generator and the current reactive power of generator. However, all generators could not affect on the whole power system. Thus, the effective generators should be selected by sensitivity analysis. The sensitivity depends on network configuration is the relation between generator reactive power outputs and reactive power loads. Using the sensitivity, the effective generator reactive reserve can be calculated.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2187-2189
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• 2001

The proposed algorithm has produced the rules of relationship between the load voltage, current, discharging electric power and ampere-hours, electric power capacity of battery on the basis of the data. Which were acquired through the battery discharging experiment that is defined by the battery's ambient temperature and various load conditions. Especially, by calculating the parameter of second order polynomial equation relation between the remaining capacity and the electric power, the algorithm is proposed adapting for the discharging pattern. And as the depth of discharging is increasing, the calculation-method of electric power is applied to decrease the accumulated error in the calculation method of capacity accumulation. Also, the proposed algorithm has compensated the temperature considering the capacity change of battery to the temperature.

• Progress in Superconductivity and Cryogenics
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• v.21 no.1
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• pp.6-9
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• 2019

Developing a gate-tunable, scalable, and topologically-protectable supercurrent qubit and integrating it into a quantum circuit are crucial for applications in the fields of quantum information technology and topological phenomena. Here we propose that the nano-hybrid supercurrent transistors, a superconducting quantum analogue of a transistor, made of topological insulator nanowire would be a promising platform for unprecedented control of both the supercurrent magnitude and the current-phase relation by applying a voltage on a gate electrode. We believe that our experimental design will help probing Majorana state in topological insulator nanowire and establishing a solid-state platform for topological supercurrent qubit.

• Korean Journal of Materials Research
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• v.1 no.3
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• pp.125-131
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• 1991

Boron penetration phenomenon of $p^{+}$ silicon gate with as-deposited amorphous or polycrystalline Si upon high temperature annealing was investigated using high frequency C-V (Capacitance-Volt-age) analysis, CCST(Constant Current Stress Test), TEM(Transmission Electron Microscopy) and SIMS(Secondary Ion Mass Spectroscopy), C-V analysis showed that an as-deposited amorphous Si gate resulted in smaller positive shifts in flatband voltage compared wish a polycrystalline Si gate, thus giving 60-80 percent higher charge-to-breakdown of gate oxides. The reduced boron penetration of amorphous Si gate may be attributed to the fewer grain boundaries available for boron diffusion into the gate oxide and the shallower projected range of $BF_2$ implantation. The relation between electron trapping rate and flatband voltage shift was also discussed.

• Journal of the Korean Society for Heat Treatment
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• v.23 no.1
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• pp.23-28
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• 2010

The cylindrical magnetron sputtering has not been widely used, although this system is useful for only certain types of applications such as fiber coatings. This paper presents electrode configurations which improved the complicacy of the target assembly by using the positive voltage power supply. It is a modified type which has a target constructed with a large cylindrical part, a conical part and a small cylindrical part. When positive voltage was applied to an anode, a stable glow discharge was established and a high deposition rate was obtained. The substrate bias current was monitored to estimate the effect of ion bombardment. As a result, it was found that the substrate current was large. With cylindrical and conical cathode magnetron sputter deposition on the surface of the substrate to prevent re-sputtering, ion impact because it can increase the effectiveness with excellent ductility and adhesion of Ti film deposition can be obtained. We board at the front end of the ground resistance of $5\;k{\Omega}$ attached to the substrate potential can be controlled easily, and Ti film deposition with excellent adhesion can be obtained. Microstructure and morphology of Ti films deposited on pure Cu wires were investigated by scanning electron microscopy in relation to preparation conditions. High level ion bombardment was found to be effective in obtaining a good adhesion for Cu wire coatings.