• Journal of IKEEE
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• v.18 no.3
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• pp.409-419
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• 2014

This paper proposes a new temperature control algorithm and system configuration of the pTMS(personal Thermal Massage System). By controlling the pulse width of the PWM(Pulse Width Modulation), the temparature of the heating lamp can be controlled stably, which is indispensable to the massage function. This technology is also adapted to the 'thermal massage', 'thermal acupressure', 'thermal moxibustion' functions of medical equipments. The temperature could be set at between $40^{\circ}C{\sim}70^{\circ}C$ by increments of $5^{\circ}C$, the control could be made in real time by increments of $1^{\circ}C$, and the temperature is displayed on the monitor by triggering every 2 seconds. when the present temperature is equal to the preset temperature, the PWM signal is minimized, and when the present temperature is higher than the preset temperature, overheating is prevented by interrupting the PWM output signal. When the difference of temperature exceeds $4^{\circ}C$, the PWM control is maximized in order for the system to reach the target temperature within a short period of time.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.961-966
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• 2009

This paper presents precise temperature control of oil outlet in an oil cooler with hot-gas bypass control as an industrial refrigerator. The control system was designed for obtaining precise temperature control performance even though abrupt disturbances based on flow rate control of hot-gas bypass. PID controller was adopted in feedback control system. We showed that the gain of PID could be easily determined by using gain-tuning methods without any numerical model. Through some experiments, excellent control performances such as overshoot within 1.7%, steady state temperature error within ${\pm}0.1^{\circ}C$ were established by a simple PI controller. We expect that the system can control the target temperature within error of $0.33^{\circ}C$ under abrupt disturbances.

• Journal of Power Electronics
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• v.8 no.2
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• pp.121-130
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• 2008

This paper introduces a design and implementation of a digital control unit for an Oxygenaire Servo Baby Incubator. The control unit is designed and implemented according to international standards. The control unit is based on an AVR Atmel microcontroller unit. It is built for monitoring and control and displays the three main temperature values: set point temperature, baby skin temperature and air temperature. User friendly software is implemented. The implemented control unit was tested in the laboratory as well as in the field. The control unit is sensitive to change of $0.1^{\circ}C$. At startup, based on a unique control strategy, the incubator reaches its steady state in about 14 minutes. The system schematic diagrams are shown in the paper. Also, programs flow charts are presented. The control unit was designed and implemented based on a contract between the Electronics Research Institute (ERI) and ENGIMED Company. The authors would like to thank ERI and ENGIMED for introducing all required finance and shoring to complete this work.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.28-31
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• 1997

This paper describes the quick and precise controlling method for home-applied refrigerator. The proposed controller is based on the fuzzy logic control method and is designed for better performance in maintaining the constant temperature of the refrigerator. The temperature of the refrigerator is controlled by the cooling air blowing fan motor which is put on, off according to fuzzy logic controller. Finally, I study the performance of the proposed controller through the computer simulation about the approximated model of the refrigerator.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.110-113
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• 2002

This paper propose a method for the temperature control using cool-plate in the track equipment. The employed control algorithm is PID control algorithm. The control gains are found using relay auto-tuning algorithm. After that the gains are adjusted manually in trial and error. The control hardware circuit is designed and implemented in the lab. The controlled temperature reached the desired value Within $\pm0.05^{\circ}C$ accuracy.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.62-62
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• 2000

An auto-tuning PID controller which is adequate for temperature control is developed based on relay-control and pole-placement Using the critical frequency which is obtained from relay-control parameters of assumed model are identified. Pole/zero-placement PID controller is designed for the identified model. The desired pole/zeros are determined so that the closed-loop has overshoot free step response. The developed auto-tuning PID controller was successfully applied to the temperature control of RTP.

• Journal of the Korean Solar Energy Society
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• v.31 no.5
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• pp.140-145
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• 2011

In this study, the performance and behavior of solar heating system according to the system control scheme, variable flow control (proportional control) and constant flow control (on-off control) was carried out by experiment. The on-off control is used generally for solar thermal system by now. But the proportional control is used for the solar district heating system which is supplied the higher temperature of water than that of desired. The proportional control logic that pump speed is varied in an attempt to maintain a specified outlet temperature of solar heating system was developed and tested for the use widely for the small and medium solar thermal system. The results are as following. First, the proportional controller which is made here could be adopted the characteristics for setting temperature control. Second, the proportional control is better than the on-off control in the side of the performance of thermal stratification in storage tank. Third, the operating energy(electricity consumption by pump) of solar thermal system can be saved more than 60% using the proportional control comparing to the on-off control.

• Journal of Bio-Environment Control
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• v.10 no.1
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• pp.42-49
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• 2001

This study was carried out to develop a fuzzy control technique of ventilation window for controlling a temperature in a greenhouse. To reduce the fuzzy variables, the inside air temperature shop was taken as one of fuzzy variables, because the inside air temperature variation of a greenhouse by ventilation at the same window aperture is affected by difference between inside and outside air temperature, outside wind speed and the wind direction. Therefore, the antecedent variables for fuzzy algorithm were used the control error and its slop, which was same value as the inside air temperature slop during the control period, and the conclusion variable was used the window aperture opening rate. Through the basic and applicative control experiment with the control period of 3 minutes the optimum ranges of fuzzy variables were decided. The control error and its slop were taken as 3 and 1.5 times compared with target error in steady state, and the window opening rate were taken as 30% of full size of the window aperture. To evaluate the developed fuzzy algorithm in which the optimized 19 rules of fuzzy production were used, the performances of fuzzy control and PID control were compared. The temperature control errors by the fuzzy control and PID control were lower than 1.3$^{\circ}C$ and 2.2$^{\circ}C$ respectively. The accumulated operating size of the window, the number of operating and the number of inverse operating for the fuzzy control were 0.4 times, 0.5 times and 0.3 times of those compared with the PID control. Therefore, the fuzzy control can operating the window more smooth and reduce the operating energy by 1/2 times of PID control.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1997.11a
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• pp.20-26
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• 1997

The design or analysis of beehouse inside temperature environment based on steady heat transfer theory causes much deviation and theoretically it is impossible to control the inside temperature lower than the outside temperature under the condition that the bee produces heat and no cooling equipment is installed. But in practical use of beehouse, the inside temperature is somehow lower than the outside temperature because of the heat inertia of concrete floor. (omitted)

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.457-461
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• 1988

In this study an one-board micom controlled precision temperature control system has been developed. The digital temperature control system is consisted of an one-board micom as digital controller, a 12-bit A/D and D/A converter, a power amplifier, a NTC thermister, a preamplfier and a heat chamber. An operating control program for the control system was written in Z80 machine language. A Dual-PID predictor control algorithm was proposed. Experments were conducted with different sampling time and limitted error value. As a result, the temperature in a heat chamber can be well controlled within +- 0.2 .deg.C when the sampling time was applied to 10 sec and the limitted error value +- 0.5 .deg.C under the dual-PID predictor control algorithm. By means of one-board micom overall system has been reduced in size and volume, thus the system becomes compact and less expensive.