• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.3
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• pp.288-292
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• 2010

Recently, in energy storage system, the EDLC is paid attention as a new environmentally friendly energy storage element. This capacitor has higher energy density than the electrolytic capacitor. Also, this capacitor has a lot of advantage such as no maintenance, longer life cycle and faster charge-discharge time than the battery system. But the EDLC must have a each charge-discharge controller to effectively control, an energy design method circuit to use effectively energy, and several compensation techniques to control a optimal operating. In this respect, this study suggests major parameters to effectively represent the characteristics of EDLC, the measurement methods of those parameters have been investigated with experiments, and the interpretation about the buck/boost DC/DC converter for the operation of EDLC.

• Proceedings of the KIEE Conference
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• 2005.10c
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• pp.114-117
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• 2005

Auto Steering System is the device for course keeping or course altering to ship's steering system. The Purpose of automatic steering system is to keep the ship's course stable with the minimum course and rudder angle. Recently, modern control theories are being used widely in analyzing and designing the ship system. Though P.D type auto pilots are widely used in ships, the stability and the adjusting methods are not clarified. In this paper the authors proposed auto steering system with Fuzzy Logic Controller. In the fuzzy control the things that the actual operators of a steering wheel has acquired through their experience can be logically described by the Lingustic Control Rule. The characteristic of the control system were investigated through the computer simulation results. it was found that the fuzzy logic control was more efficient than the conventional system.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.217-224
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• 2000

This paper proposes a new type of HDD suspension integrated with shape memory alloy(SMA) actuator in order to prevent the friction between the slider and the disk. A finite element analysis is undertaken to investigate modal characteristics of the proposed self loading/unloading slider. The dynamic model is formulated and its validity is proved by comparing the predicted displacement transmissibility with the measured one. A control model is then established by integrating experimentally-obtained SMA actuator dynamics. Subsequently, a sliding mode controller is designed to achieve non-contact start/stop(Non CSS) modes, and control results are presented in time domain.

• Proceedings of the IEEK Conference
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• 2004.06b
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• pp.355-358
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• 2004

In this work, N-LDMOSFET(Lateral Double diffused MOSFET) was designed and fabricated on SOI(Silicon-On-Insulator) substrate, for such applications as motor controllers and high voltage switches, fuel injection controller systems in automobile and SSR(Solid State Rexay)etc. The LDMOSFET was designed to overcome the floating body effects that appear in the conventional thick SOI MOS structure by adding p+ region in source region. Also, RESURF(Reduced SURface Field) structure was proposed in this work in order to reduce a large on-resistance of LDMOSFET when operated keeping high break down voltage. Breakdown voltage was 268v in off-state ($V_{GS}$=OV) at room temperature in $22{\mu}m$ drift length LDMOSFET. When 5V of $V_{GS}$ and 30V of $V_{DS}$ applied, the on resistance(Ron), the transcon ductance($G_m$) and the threshold voltage($V_T$) was 1.76k$\Omega$, 79.7uA/V and 1.85V respectively.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.892-896
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• 2001

Investigation is performed on the stability of nonlinear system under turbulent fluid motion modelled as white noise random process, which is a preliminary result in the course of research on the characteristic and nonlinear control of the stochastic system. Adopted physical model is beam-type structure with tip-mass and main base mass. The governing equation is derived via F-P-K approach in stochastic sense. By means of Gaussian Closure method infinite dynamic moment equations due to system nonlinearity is closed to finite one. At the best of authors' knowledge, it is the first trial to design nonlinear controller by using of sliding mode technique in stochastic domain and control performance and effect in stochastic domain is studied.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.10
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• pp.1957-1963
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• 2017

This paper has proposed a new-type groundwater auto-monitoring system based on Multi-Sensor Device. The system adopted Multi-Sensor Device as host computer of data acquisition, used Windows Mobile which was prevalent operation system of Multi-Sensor Device. It adopted serial port CAN and RS485 as the communication interface between goundwater sensor Device and monitor host machine and utilized serial-linked multi-sensor design to measure effectively according to the depth of groundwater. We present a design for a groundwater monitoring system based on a network of wirelessly linked sensors. The proposed solution will enable groundwater researchers and decision makers to have quick access to the groundwater data with less effort and cost. Though our design is initially meant for groundwater monitoring, it can be easily adapted to other fields of environmental monitoring.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.4
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• pp.310-315
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• 2015

Purpose: The purpose of this study was to measure the tightening torque for dental implant in dental laboratory and to analyze of the effects of different tightening torque. Materials and Methods: The tightening torque for dental implant in dental laboratory were measured by digital torque gauge. The length of abutment and analog were measured as tightening torque of manufacturer's instructions and the measured value. And the data were statically analyzed. Results: The mean tightening torque of implant screw in dental laboratory was $1.563{\pm}0.332Ncm$. The external type implant system of total length were showing no significant differences but the internal type implant system had difference significant (P < 0.05) when compared with tightening torque. Conclusion: The implant prosthesis should be made under manufacturer's instructions especially as tightening torque of screw. For the fidelity of implant prosthesis, dental technician should learn how to use the torque gauge.

• Food Science of Animal Resources
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• v.40 no.5
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• pp.813-830
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• 2020

In this study, the potential of infrared assisted freeze-drying (IRAFD) was tested for the production of shelf-stable edible insects: Protaetia brevitarsis larva (larva of white-spotted flower chafer). The IRAFD system was customized using an infrared lamp, K-type thermocouple, controller, and data acquisition system. The infrared lamp provided the sublimation energy for rapid freeze-drying (FD). The IRAFD conditions were continuous IRAFD-5.0 kW/㎡ and IRAFD-5.0 kW/㎡ at different weight reduction (WR) (10%, 20%, and 30%). The continuous IRAFD reduced the drying time to 247 min compared to the 2,833 min duration of FD (p<0.05). The electrical energy could be reduced by more than 90% through infrared radiation during FD (p<0.05). The Page model resulted in the best prediction among the tested drying kinetic models. In terms of quality, IRAFD showed significantly lower hardness, chewiness, and higher protein levels than hot air drying and FD (p<0.05). IRAFD better preserved the glutamic acid (6.30-7.29 g/100 g) and proline (3.84-5.54 g/100 g). The external product appearance after IRAFD exhibited more air pockets and volume expansion, which might result in a good consumer appeal. In conclusion, this study reports the potential of IRAFD in producing shelf-stable and value-added edible insects.

• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.417-420
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• 1990

The conventional quantitative techniques of system analysis are intrinsically unsuited for dealing with humanistic systems. Therefore, the rule based modeling of fuzzy linguistic type has been developed for the analysis of humanistic systems and complex systems and it is very significant for analysis and design of fuzzy logic controller. The activated sludge process is a commonly used method for treating sewage and waste waters. A mathematical tool to build a fuzzy model of the activated sludge process where fuzzy implications and linear reasoning are used is presented in here. A root-mean square error is used as the criterion of the fuzzy model's adequacy to the A.S.P. and the least square method is used for the identification of optimum consequence parameters. A method of modeling of the activated sludge process using its input-output data and simulation results for its application are shown.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.54 no.3
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• pp.141-147
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• 2005

In this paper, We are going to propose the fire protection system with using CAN(Controller Area Network). The larger, higher and deeper buildings are, the more dangerous people are when fire happens. We should be aware of the problems of prior fire protection system. Therefore, we construct embedded system based on CAN communication that is capable of N:N communication, and build independent fire protection system. If the fire is occurred on the building, the problem is that how fast we can detect the fire and put off it by using available system. this is major factor that reduces damage of our wealth. therefore in this studies We would like to design more stable system than current system. this system that is based on CAN communication which is available N:N communication constructs and is designed to compensate for each fault so that our aim is to reduce the line of system and cost of installation and to suppose future type fire protection system. We are simulated by NIST FDS(Fire Dynamics Simulator) to prove the efficiency of this system.