• 제어로봇시스템학회:학술대회논문집
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• 1988.10b
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• pp.804-809
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• 1988

PRNM(Power Range Neutron Monitoring) of BWR (Boiling Water Reactor) is a system that processes signals from about two hundred LPRM (Local Power Range Monitor) sensors in the nuclear reactor and this system monitors the neutron flux level during the plant operating region. Development has been made by employing a special technique for multiplexing neutron sensor signals and the recent advanced microelectronics technology. It is applicable to the total plant digital control system for a nuclear power plant.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.224-225
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• 2012

When Power Factor Correction(PFC) boost converter is designed for the universal input range, unwanted burst operation can be found at high line and light load. This operation may cause an audible noise from the boost inductor or sensitive flicker for human eye can be found in case of the display application. In order to solve this difficulty, this paper proposes the new control range compensation method and shows the effectiveness than the conventional method thru the experimental result.

• Journal of the Optical Society of Korea
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• v.7 no.2
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• pp.89-96
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• 2003

A new method to control the free spectral range of a long period fiber grating is proposed and theoretically analyzed. As the refractive index decreases radially outward in the silica cladding due to graded doping of fluorine, waveguide dispersion in the cladding modes was modified to result in the effective indices change and subsequently the phase matching conditions for coupling with the core mode in a long period fiber grating. Enlargement of the free spectral range in a long period fiber grating was theoretically confirmed.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.4
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• pp.584-591
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• 2012

To evaluate the role of using forage, shade and shelterbelts in attracting birds into the range, three trials were undertaken with free range layers both on a research facility and on commercial farms. Each of the trials on the free range research facility in South Australia used a total of 120 laying hens (Hyline Brown). Birds were housed in an eco-shelter which had 6 internal pens of equal size with a free range area adjoining the shelter. The on-farm trials were undertaken on commercial free range layer farms in the Darling Downs in Southeast Queensland with bird numbers on farms ranging from 2,000-6,800 hens. The first research trial examined the role of shaded areas in the range; the second trial examined the role of forage and the third trial examined the influence of shelterbelts in the range. These treatments were compared to a free range area with no enrichment. Aggressive feather pecking was only observed on a few occasions in all of the trials due to the low bird numbers housed. Enriching the free range environment attracted more birds into the range. Shaded areas were used by 18% of the hens with a tendency (p = 0.07) for more hens to be in the paddock. When forage was provided in paddocks more control birds (55%) were observed in the range in morning than in the afternoon (30%) while for the forage treatments 45% of the birds were in the range both during the morning and afternoon. When shelterbelts were provided there was a significantly (p<0.05) higher % of birds in the range (43% vs. 24%) and greater numbers of birds were observed in areas further away from the poultry house. The results from the on-farm trials mirrored the research trials. Overall 3 times more hens used the shaded areas than the non shaded areas, with slightly more using the shade in the morning than in the afternoon. As the environmental temperature increased the number of birds using the outdoor shade also increased. Overall 17 times more hens used the shelterbelt areas than the control areas, with slightly more using the shelterbelts in the afternoon than in the morning. Approximately 17 times more birds used the forage areas compared to the control area in the corresponding range. There were 8 times more birds using a hay bale enriched area compared to the area with no hay bales. The use of forage sources (including hay bales) were the most successful method on-farm to attract birds into the range followed by shelterbelts and artificial shade. Free range egg farmers are encouraged to provide pasture, shaded areas and shelterbelts to attract birds into the free range.

• Journal of Electrical Engineering and Technology
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• v.10 no.5
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• pp.2052-2056
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• 2015

This Paper analyzes the characteristics of the WRSM in high-speed operation range. To verify the control characteritics of various WRSM models, the relative position of the central point of current limit circle and voltage limit ellipse is defined as M value and 3 models according to M_max value are designed through inductance change. Through the designed models, the current control method of 3-variables control for maximum power especially in high-speed operation range is presented.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.1
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• pp.69-76
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• 2009

This paper describes sensorless high-speed control for 45,000rpm/22kw type PMSM by using iterative adaptive sliding mode observer. The proposed algorithm is based on sensorless vector control by on-line estimating the speed of rotor in the wide speed operating range between the starting operation. In addition, it shows the enhanced performance of the iterative adaptive observer by lessening its chattering and getting stable response in limited PWM period. The simulation and experiment results show the reliable performance of the proposed algorithm through starting to high speed operating range.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.14 no.1
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• pp.41-48
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• 2014

This paper analyzes the Monte Carlo localization (MCL) method, which estimates the pose of an indoor mobile robot. A mobile robot must know where it is to navigate in an indoor environment. The MCL technique is one of the most influential and popular techniques for estimation of robot position and orientation using a particle filter. For the analysis, we perform experiments in an indoor environment with a differential drive robot and ultrasonic range sensor system. The analysis uses MATLAB for implementation of the MCL and investigates the effects of the control parameters on the MCL performance. The control parameters are the uncertainty of the motion model of the mobile robot and the noise level of the measurement model of the range sensor.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.474-476
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• 1999

This paper presents the vector control of induction motor for traction drives. Especially, the PWM mode control method is well described to be selected as the change of speed to meet the wide speed range of the traction motor. Asynchronous space vector PWM mode and synchronous one pulse mode are basically used under the full speed range with the overmodulation PWM mode for the soft transfer between them. The validity of this proposed control scheme is verified with the simulation results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.297-300
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• 2005

This paper presents vibration control of an engine mount for a passenger vehicle utilizing ER fluid and piezoelectric actuator. The proposed engine mount can be isolated the vibration of wide frequency range with many types of amplitude. The main function of ER fluid is to attenuate vibration for low frequency with large amplitude, while the piezoelectric actuator is activated in hish frequency range with small amplitude. A mathematical model of the engine mount is derived using Hydraulic model and mechanical model. After formulating the governing equation of motion, then field-dependent dynamic stiffness of the engine mount is evaluated for various engine speed and excitation amplitude conditions. Then robust controller is designed to attenuate vibration of wide range frequency component. Computer simulation is undertaken in order to evaluate the vibration control performance such as transmissibility magnitude in frequency domains.

• Nuclear Engineering and Technology
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• v.56 no.4
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• pp.1398-1406
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• 2024

The control rod worth is a key safety parameter required to be measured in commercial pressurized water reactors (PWRs). Conventionally, the control rod worth is measured after reaching the critical state, which occupies the considerable time in the zero-power physics test. In this study, an efficient control-rod worth measurement technique has been proposed based on the improved neutron-source multiplication method, which can be implemented with the source-range detector count rates in the subcritical states. Moreover, the noise reduction technique has been adopted to smooth the large fluctuation existing in the original signals. In order to verify the engineering performance of the proposed measurement technique, the measured source-range detector count rates during the rod withdrawal process before reaching critical state in a CNP1000 reactor have been employed. It demonstrated that almost all estimated results of control rod worth satisfy the engineering acceptance criteria, except one control rod with the relative difference over 10 %, which indicates the capability of the proposed method in estimating control rod worth.