• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.10
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• pp.690-696
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• 2004

This paper is proposed a hybrid intelligent controller based on the vector controlled surface permanent magnet synchronous motor(SPMSM) drive system. The hybrid combination of neural network and fuzzy control will produce a powerful representation flexibility and numerical processing capability. Also, this paper is proposed speed control of SPMSM using neural network-fuzzy(NNF) control and speed estimation using artificial neural network(ANN) Controller. The back propagation neural network technique is used to provide a real time adaptive estimation of the motor speed. The error between the desired state variable and the actual one is back-propagated to adjust the rotor speed, so that the actual state variable will coincide with the desired one. The back propagation mechanism is easy to derive and the estimated speed tracks precisely the actual motor speed. This paper is proposed the theoretical analysis as well as the simulation results to verify the effectiveness of the new method.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.8
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• pp.545-550
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• 2004

This paper is proposed a fuzzy neural network controller based on the vector controlled induction motor drive system. The hybrid combination of fuzzy control and neural network will produce a powerful representation flexibility and numerical processing capability. Also, this paper is proposed estimation and control of speed of induction motor using ANN Controller. The back propagation neural network technique is used to provide a real time adaptive estimation of the motor speed. The error between the desired state variable and the actual one is back-propagated to adjust the rotor speed, so that the actual state variable will coincide with the desired one. The back propagation mechanism is easy to derive and the estimated speed tracks precisely the actual motor speed. This paper is proposed the theoretical analysis as well as the simulation results to verify the effectiveness of the new method.

• Journal of dental hygiene science
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• v.5 no.4
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• pp.221-225
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• 2005

In this study, survey is conducted to make aware of importance which personal protection was accomplished at the dentistry. It investigated the performance of infection control and X-ray safety management to the third grade of D-Health College. 1. The infection control is recognized to high level and practiced certainly at actual training of oral prophylaxis. 2. The infection control is recognized to low level relatively at actual training of radiography. 3. The infection control is not practiced at actual training of radiography except for the film holder. 4. The X-ray safety management is recognized to high level and conducted certainly at actual training of radiography. To consider the above result, the infection control is not nearly practiced at radiography. In accordance with, the education must be demanded that the infection control is practiced throughly at radiography for raising a necessary against the recognization and practice of the infection control.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.243-246
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• 2009

Importance of quality control is gradually increasing in the construction. And the reber work is very important things which influence in safety and durability of the building and accounts for about 9.8% of the total cost. Although reber work is important, quality control of the rebar work is still performed by attitude and experience of worker. Therefore, it is very important to quality achievement effort and quality standards recognition of rebar worker for quality sophistication in the construction. Some papers have dealt with the quality control in construction. But there was no study for actual conditions of quality standards recognition of rebar workers. The purpose of this study is to survey the actual conditions of quality standards recognition of rebar workers and to analyze difference of consciousness of administrator and worker. The result are : there id difference of consciousness of worker and administrator, workers work without knowing quality standard.

• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.1
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• pp.53-59
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• 2017

The information on the actual voltages and actual currents of the motor is required for the sensorless control of a permanent magnet synchronous motor without rotor position sensors. In the model-based rotor position estimator of a PM synchronous motor, the reference voltages, which are the outputs of the current controller, are commonly used. The reference voltages in over-modulation regions for high-speed operation differ from the actual voltages applied to the motor. Consequently, the estimated rotor position and rotor speed may fail to track the real rotor position and real rotor speed. In this paper, the sensorless control for a PM synchronous motor in over-modulation regions for high-speed operation is proposed. The three-phase voltages applied to the motor are measured by using additional voltage detection circuits, and the performance of the rotor position estimator based on the measured three-phase voltages is validated through the experimental results.

• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.2
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• pp.112-119
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• 2009

This paper presents a PLL(Phase Lock Loop) approach for effective speed and torque control of high speed miniature BLDCM(Brushless DC Motor) using hall sensor. The proposed speed control method based on PLL uses only a phase shift between reference pulse signal according to speed reference and actual pulse signal from hall sensor. It doesn't use any speed calculation, and calculates a direct current reference from phase shift. The current reference is changed to reduce the phase shift between reference and actual pulse. So the actual speed can keep the reference speed. The proposed control scheme is very simple but effective speed control is possible. In order to obtain a smooth torque production, the reference current is changed using acceleration and deceleration slope. The proposed control scheme is verified by experimental results of the 50W, 40,000[rpm] high speed miniature BLDCM.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.11
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• pp.9-20
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• 1998

In recent manufacturing process, the increase of productivity has been attempted by reducing machining time with the increase of cutting force. However, the excessive increase of cutting force can cause tool breakage and have a bad effect on both manufacturing machine and workpiece. Thus, it is necessary to estimate and control the cutting force in real time during the process. In this study, use of disturbance observer is proposed for the indirect cutting force estimation. The estimated cutting force is used for the real-time control of feedrate, making the actual cutting force follow the reference force command. Since the suggested method does not need an expensive sensor like a dynamometer, the method is expected to be used practically. Since the actual cutting force follow the reference force, resulting the reducing of the machining time the increase of productivity are also expected, and the quality of cutting surface has been improved due to the adjusted feedrate. Besides, an actual constant cutting force guarantees the prevention of tool breakage. To show the effectiveness of the suggested cutting force control method, an experimental setup has been made without sensor and applied to several workpieces. Experiments show that the suggested method is effective to cutting force control of a CNC machining center.

• Journal of Korean Academy of Nursing
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• v.27 no.4
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• pp.765-776
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• 1997

Hospitals accomodate patients who have a high risk of infection due to reduced immunity as well as people who require surgical, medical or other treatments. Consequently, the role of clinical nurses, who come into close contact with these patients is very important in the control of nosocomial infection. This study was done to investigate and compare the level of perception of the importance of the control of nosocomial infections as well as the level of actual performance, and the level of satisfaction with the control of nosocomial infection by the clinical nurses. Thus, the purpose of this study is to contribute basic data for improving policies and educational programs to control nosocomial infection. A summary of the survey results is as follows. 1) The means of scores on all categories of the inquiry were 4. 51 for awareness 4.42 for actual performance, and 3.20 for satisfaction, of a possible high score of 5.00. 2) Correlations of the level of perception of importance between characteristics of nurses and hospital control of nosocomial infection differed significantly according to the type of hospital establishment type (p=.005), age(p=.000), career(p=.000), position (p=.002), and regular conferences on infection control in working departments(p=.003), Correlation of the level of actual performance between characteristics of nurses and hospital control of nosocomial infection diffesed significantly according to type of hospital(p=.000), hospital size (p=.009), working department(p=.000), age(p=.000), career (p=.000), school career(p=.040), position (p=.000), education experience on nosocomial infection(p=.020), and regular conferences on infection control in working department(p=.000). Correlation of degree of satisfaction between characteristics of nurses and hospital control of nosocomial infection also differed significantly according to the type of hospital establishment (p=.003), working department(p=.000), age (p=.000), and regular conferences on infection control in working department (p=.000). 3) Correlation between clinical nurses, level of perception of importance and actual level of performance for the control of nosocomial infection was relatively positive (r=.57, p=.000). Correlation between clinical nurses degree of satisfaction and level of actual performance for control of nosocomial infection was relatively positive (r=.47, p=.000). Correlation between clinical nurses, level of perception of importance and degree of satisfaction degree with the control of nosocomial infection was also relatively positive (r=.27, p=.000).

• Korean Journal of Community Nutrition
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• v.8 no.1
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• pp.53-61
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• 2003

This study was designed to explain the intentions and consumption of dairy foods among university female students. The factors related to intentions of consumption or actual consumption of dairy foods were identified within the theory of planned behavior. The survey questionnaire, developed using open-ended questions (n=35) , was administered to university female students (n:184) Subjects completed information regarding attitudes, subjective norms, perceived control, intentions and consumption of dairy foods. Correlation analysis and multiple regression were used to study the association of factors with intentions and consumption of dairy foods. Subjects showed relatively low intention to consume dairy foods (-0.4 $\pm$ 1.6 from a scale of -4-14). They ate 1.2 $\pm$ 0.9 servings of dairy foods a day and 52.2% of subjects had less than a serving a day, showing inadequate consumption of dairy foods. All three factors, attitudes, subjective norms and perceived control were significantly correlated to the intentions to take dairy foods regularly (r : 0.26-0.27) . Multiple regression results, however, revealed that subjective norms (p < 0.01) and perceived control (p < 0.05) contributed to the model of explaining intentions, while attitudes did not (model $R^2$ : 0.154) . To predict and explain actual consumption of dairy foods, two regression models were examined. In the first model, perceived control was significant in predicting dairy foods consumption, while attitudes and subjective norms were not. In the second model, intentions and perceived control were significantly related to actual consumption of dairy foods, providing the empirical evidence of the theory (model $R^2$: 0.121) These results suggest that perceived control was significant in explaining actual behavior as well as intentions. This study suggests that nutrition education to increase dairy foods consumption for young adults should focus on increasing perception of control and eliciting social support from respected others.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.61 no.4
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• pp.153-160
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• 2012

This paper is written for the development of boiler combustion air control algorithm of coal-fired power plant by the steps of design, coding and test. The control algorithms were designed in the shape of cascade control for two parts of air master, forced draft fan pitch blade by standard function blocks. This control algorithms were coded to the control programs of distributed control systems under development. The simulator for coal-fired power plant was used in the test step and automatic control, sequence control and emergency stop tests were performed successfully like the tests of the actual power plant. The reliability will be obtained enough to apply to actual site if the total test has been completed in the state that all algorithms were linked mutually. It is expected that the project result will contribute to the safe operation of domestic power plant and the self-reliance of coal-fired power plant control technique.