• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.7
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• pp.993-1000
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• 2018

This paper proposes a low-dropout voltage regulator(LDO) using self-cascode structure. The self-cascode structure was optimized by adjusting the channel length of the source-side MOSFET and applying a forward voltage to the body of the drain-side MOSFET. The self-cascode of the input differential stage of the error amplifier is optimized to give higher transconductance, but the self-cascode of the output stage is optimized to give higher output resistance, The proposed LDO using self-cascode structure was designed by a $0.18{\mu}m$ CMOS technology and simulated using SPECTRE. The load regulation of the proposed LDO regulator was 0.03V/A, whereas that of the conventional LDO was 0.29V/A. The line regulation of the proposed LDO regulator was 2.23mV/V, which is approximately three times improvement compared to that of the conventional LDO. The transient response of the proposed LDO regulator was 625ns, which is 346ns faster than that of the conventional LDO.

• Korean Journal of Culture and Arts Education Studies
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• v.9 no.3
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• pp.45-61
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• 2014

Recently, there is a discussion about culture theory in the area of traffic safety regulation. It has the view that the subject of criticism, etc. by drivers' regulation interpretation, awareness about the danger of regulation violation and nonacceptance of regulation can be changed according to the way drivers' cultural bias was formed. According to the culture theory, fundamental views of the world in particular social relations surrounding individuals, world view or cosmology, are formed and the world view makes an effect on individual behavior and attitude. In this context, cultural cognition and cultural learning theory which are suggested in Christoph Wulf's study on historical-cultural anthropology provide new approach toward this phenomenon. According to his insistence, core mechanisms which can explain cultural cognition and cultural learning are systematized by five things; physical characteristic, mimesis, performance theory, rite and image. The purpose of this research is to investigate the changes by the way Korean people cognize traffic regulations culturally and experiences of traffic regulation violation through the analytic frame of Christoph Wulf's five core mechanisms. To achieve it, cognition of traffic culture was analyzed by analytical phenomenology for drivers who had been educated due to their violation of traffic regulations. Value, lifestyle and practicing methods which are pursued by people work in sociocultural context rather than are influenced by cognitive structure of individuals.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.3
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• pp.10-16
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• 2005

Recently, the international regulations about the exhaust emissions of the motorcycle have been strengthened. The electrically controlled fuel injection type motorcycle has been emphasized to meet with this regulation. However, since the pulsation phenomenon happens in the intake port of the motorcycle because of the characteristic of high speed and the smaller layout than the passenger car, there are many difficulties to select the factor about control parameters needed to develop the ECU system. In this paper, the pulsation values measured from the engine test were compared with the calculated one by WAVE, and it was analyzed the pulsation characteristic according to the driving condition and estimated the mass flow rate. This research showed that the lowest point of the pressure gets lowin the low load and the pulsation of pressure were increased in the high load. Also, the simulation program was verified by showing good prediction of the pulsation and air mass flow rate.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.1
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• pp.53-60
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• 2012

As enforced by the regulation on the improving fuel efficiency and increased the demand on green technology, many interests are focused on electric vehicles and hybrid vehicles. Thus the technology development in electrification of vehicle operation system, including steering and braking field, is actively progressive. Especially electric power steering substitutes for hydraulic power steering rapidly in the market, which is more complex and bigger in packaging volume compared with electric power steering system. The core component in electric power steering system is a motor, which is required to be silent and powerful to guarantee required system performance. Brushless synchronous motors are widely used and many variations of the motors are introduced in the market, while the performance of each type is not well defined or studied for electric power steering system. In this paper, recent developments in brushless synchronous motor are reviewed and compared applying finite element analysis in electromagnetic field. As results, each characteristic of different types of brushless synchronous motors is compared and summarized for optimized selection in electric power steering system.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2051-2053
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• 1998

In spite of nonlinear or step-changing load and line disturbances, the inverter for the UPS must provide the pure sinusoidal output voltage with low THD(Total Harmonics Distortion). This paper proposes an inverter controller for the UPS which has a good dynamic response characteristic and robustness for applying industrial world directly. The inverter output voltage is controlled instantaneously with a double regulation loop by a TMS320C31 Digital Signal Processor so that it has very good dynamic response for nonlinear or step-changing load and line disturbances. To improve the voltage utilization and response characteristics, the Space Vector Modulation(SVM) technique is adapted for the switching method of this system. The characteristics of the proposed control system were verified by simulations and experiments.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.6
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• pp.180-186
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• 2009

Due to the large capacity and low cost, electrolytic capacitors with of energy storage and voltage regulation are used for almost all types of non-linear load as the DC/DC converter. Electrolytic capacitor, which is the most of the time affected by the aging effect, plays very important role for the power converter system quality and reliability. Therefore, this paper proposes a new method to detect the changes the capacitance value of an electrolytic capacitor in order to analyze the internal characteristic and worn-out state of an electrolytic capacitor. Simulation results by frequency analysis show the validity of the proposed capacitance estimation algorithm.

• Journal of the Korean institute of surface engineering
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• v.44 no.6
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• pp.277-283
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• 2011

In this study, the cavitation test and electrochemical experiments were conducted for ALBC3(Cu-Al) alloy that has an excellent corrosion resistance and cavitation characteristic in sea water. Based on the ASTMG32 regulation, the cavitation test was performed with the cavitation and cavitation erosion tester using piezoelectric effect. The electrochemical characteristics are evaluated with potentiostatic experiments in activation polarization potential range. As a result, cavitation damage is increased proportionally to temperature and time at $30{\mu}m$ amplitude. It is appeared that acceleration period in weight loss presented over 6 hours under the cavitation environment in sea water. In addition, corrosion damages were observed at the potential range of -3.2~-1.4 V as the result of potensiostatic experiments during 12 hours in activation polarization potential range.

• Journal of the Korea Society of Computer and Information
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• v.20 no.9
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• pp.73-80
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• 2015

Cyberloafing is a term used to describe the actions of employees who use their Internet access at work for personal use while pretending to do legitimate work. This research that this puts the foundation on the general deterrence theory, social control theory, and Triandis model compares the individual characteristic including the group norm, self-control, perceived value among many factors having an effect on the personal ethical decision-making besides the general principles of ethics and stipulated regulation like the severity of sanction together. It was exposed to have the effect that the severity of punishment, self control, and perceived value notes to the internet abuse action. Therefore, the education and rules of punishment which is consistent along with the theoretical thesis supporting the groping of the preparation plan that is active in the various ethic problems has to be built. It is necessary that the company devises the internet application in the appropriate range, that is the partial the affirmation feeling which and it can allow officially. According to the cognitive dissonance, since this will have to allow with the positive direction can move to the misuse action with the intention differently, it can draw a conclusion.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.120-123
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• 2002

In this study it had an excellent optical characteristic, it followed in the creation rate and the refractive index regulation to the ease. Chalcogenide produced the $As_{45}Se_{45}Te_{10}$ thin film and the $MgF_{2}$ thin film. It measured thin film plan simulation, and the thin film has a 1 -dimensional photonic band gap. The chalcogenide $As_{45}Se_{45}Te_{10}$ thin film was measured with the fact that it has a high refractive index (2.6~2.9). The $As_{45}Se_{45}Te_{10}$ and $MgF_{2}$ thin film, have a high refractive index and a low refractive index, it used a simulation and planed period 5-pairs structure, the result was from 500nm to 800nm. It will be able to confirm the characteristic which most of the incidence light reflects, the He-Ne (632.8nm) laser was irradiated in the thin film which stabilized the thin film. $As_{45}Se_{45}Te_{10}$ (high refractive index layer: H) and $MgF_{2}$ (low refractive index layer: L) results which plans the thin film with glass/LHLHLLHLHL/air structure, 632.8nm against transmitance, increased a lot. An application possibility with the filter against a specific wave length was confirmed.

• Journal of the Korea Safety Management & Science
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• v.14 no.2
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• pp.65-70
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• 2012

This study was performed to test the combustive properties of the pipe insulation materials which are mainly used in the industries and buildings. Fire characteristic test of pipe insulation film according to the KS F ISO 5660-1 was performed. The experimental materials commonly used in the pipe insulation were used four kinds of films. Two kinds of 4 types of products that have the flame retardant performance and the other two types of them have no flame retardant performance. They were selected for fire characteristic test. The result of finding 25kW/$m^2$ radiation from the ignition was that flame retardant products were 140sec and the other one were 69sec in average of heat release rate(HRR). The result of flame retardant products in the 50kW/$m^2$ was 34sec and the other one were 15sec in average of HRR. However, the HRR of flame retardant products was much higher than the other one. Flame propagation test was conducted according to the KOFEIS 1001. The result of flame retardant products was that flame retardant products had a hold without fire spread after firing them. But the other one were completely fired after firing them. Therefore, I want to recommend that flame retardant products need to be used by the regulation to prevent or decrease a fire spread.