• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.6
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• pp.647-653
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• 1988

A rapid thermal annealing system using tungsten halogen lamp has been designed and assembled. A control scheme where the temperature control is executed with calculated wafer temperature by considering the thermocouple delay rather than measured thermocouple temperature,is proposed. This control scheme gives more accurate control of the wafer temperature. In addition, the distribution of transmitted light power to the wafer in the system has been simulated, and lamp interval modification has been able to give more uniform light power distribution. Considering incident light spectrum, absorption, reflection, radiation of silicon, etc., temperature profile has been simulated. When the light power uniformity on the 3" wafer is below 1%, the temperature uniformity is about 2%.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.9
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• pp.822-830
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• 2000

A conventional advanced control algorithm is proposed in this paper for improved temperature regulation of a TV-glass melting furnace. The TV-Glass melting furnace is a typical MIMO(Multi-Input Multi Output) system which is subject to various thermal disturbances. Because of its complexity, a detailed mathematical model of the furnace is hard to establish. To design a temperature control control system of the furnace, major input-output variables are selected first, and simple FOPDT(First Order Plus Dead Time) models are established based on the physical meaning and experimental process data. Based on the FOPDT models, a multi-loop control system composed of cascade and single loops are designed for effective control of the MIMO system. Practical implementation on the 150 ton/day furnace using the DCS(Distributed Control System) showed that the proposed control technique performs better than manual control.

• Advances in concrete construction
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• v.14 no.1
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• pp.57-70
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• 2022

The spiral case concrete (SCC) used in the underground powerhouse of large hydropower stations is complex, difficult to pour, and has high requirements for temperature control and crack prevention. In this study, based on the closed-loop control theory of "multi-source sensing, real analysis, and intelligent control", a new intelligent cooling control system (ICCS) suitable for the SCC is developed and is further applied to the Wudongde large-scale underground powerhouse. By employing the site monitoring data, numerical simulation, and field investigation, the temperature control quality of the SCC is evaluated. The results show that the target temperature control curve can be accurately tracked, and the temperature control indicators such as the maximum temperature can meet the design requirements by adopting the ICCS. Moreover, the numerical results and site investigation indicate that a safety factor of the spiral case structure was sure, and no cracking was found in the concrete blocks, by which the effectiveness of the system for improving the quality of temperature control of the SCC is verified. Finally, an intelligent cooling control procedure suitable for the SCC is proposed, which can provide a reference for improving the design and construction level for similar projects.

• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2048-2054
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• 2022

The coolant temperature feedback coefficient is an important parameter of reactor core power control system. To study the coolant temperature feedback coefficient influence on the core power control system of small PWR, the core power control system is built with the nonlinear model and fuzzy control theory. Then, the uncertainty quantification method of reactor core parameters is established based on the Latin hypercube sampling method and the Bootstrap method. Finally, under the conditions of reactivity step perturbation and coolant inlet temperature step perturbation, uncertainty analysis for two cases is carried out. The result shows that with fuzzy controller and fuzzy PID controller, the uncertainty of the coolant temperature feedback coefficient affects the core power control system, and the maximum uncertainties of core relative power, coolant temperature deviation, fuel temperature deviation and total reactivity are acceptable.

• International journal of advanced smart convergence
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• v.4 no.1
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• pp.104-113
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• 2015

This paper focuses on a temperature effects on a PV panel which has been installed in Thailand. The main objective is cleaning PV panels and reduce temperature of PV panel by water injects from waterway and experimental results of PV power what it is difference. This project is designed by PLC control system which water injects and control PV temperature, In addition, this project consists of hardware and software such as water pump, water injection and PLC control has been automatically and it can be control system manually. The automatic control system is working when PV temperature rises up over 45 degree Celsius after that the pumping machine would inject water to the surface of PV panels and it must be stop when the PV panel temperature comes down less than 45 degree Celsius. The result of actual experimental found that the control system has been done correctly under specify condition. The experimental has been shown electrical data before and after water injects on PV system found that the electrical power a bit increases and The energy has been taken from PV panel less than energy consumption equipment of control system which taken to operate the water injecting system.

• Journal of Sensor Science and Technology
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• v.25 no.1
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• pp.65-70
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• 2016

We devised a method to control the temperature of a liquid bath as low as $-100^{\circ}C$ using the duty cycle control of a solenoid valve. The solenoid valve controls the flow of liquid nitrogen that we used as a cryogen in this system. By controlling the duty cycle of a solenoid valve using feedback from the measured temperature of the liquid bath, we were able to achieve temperature stability within ${\pm}19mK$ around $-100^{\circ}C$. We also demonstrated that by taking average values of the temperature readings for sequence of measurements from more than one thermometer, it is possible to use this system for the calibration of thermometers within 3 mK. This system and the control method can be used for the precise temperature control in the range between $0^{\circ}C$ and $-100^{\circ}C$, where commercially available precision baths are much expensive and hard to be built in customized configurations.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.3
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• pp.327-335
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• 2015

In this paper, we propose an independent cooling control (ICC) scheme for high strength and atmosphere corrosion resisting steel to obtain the desired temperature and properties along the longitudinal direction of the steel in the run-out table (ROT) process. A temperature model of the independent process is developed to divide the ROT into front and back sections. The control concept uses field data, problem analysis, and a time-temperature transformation diagram. The effectiveness of the proposed control is verified using simulation results under a temperature disturbance by the transformation in the middle of the ROT. The results of a hot strip mill field test show that the temperature control performance is significantly improved by the proposed control scheme.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1209-1214
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• 2009

Various automatic temperature control systems have been used widely in Korea for the conservation of heating energy and the enhancement of thermal comfort in residential buildings. But the heating control performance for automatic temperature control systems extensively vary with the design and operational conditions of the heating system, the climate condition and others. It was introduced in this study a numerical calculation program package to analyze heating control characteristics of the automatic temperature control system. This package is able to analyze the room air temperature, return water temperature, supplied heating flux and flow rate, and so on. One the other hand, the simulation results were verified by comparing with the field test results.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.17 no.4
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• pp.68-78
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• 2021

In order to solve the increasing deterioration of the energy shortage problem, ground-source heat pump (GSHP) systems have been widely installed. The control method is a significant component for maintaining the long-term performance and for reducing operation cost of GSHP systems. This paper presents the measurement and analysis results of the cooling performance of a GSHP system using capacity control with outdoor air temperature. For this, we installed monitoring equipments including sensors for measuring temperature, flow rate and power consumption, and then monitored operation parameters from July 9, 2021 to October 2, 2021. From measurement results, we analyze the effect of capacity control with outdoor air temperature on the cooling performance of the system. The average performace factor (PF) of the heat pump was 6.95, while the whole system was 5.54 over the measurement period. Because there was no performance data of the existing GSHP system, it was not possible to directly compare the existing control method and the outdoor air temperature method. However, it is expected that the performance of the entire system will be improved by adjusting the temperature of cold water produced by the heat pump, that is, the temperature of cold water on the load side according to the outside air temperature.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2011.10a
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• pp.99-100
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• 2011

In this paper, a temperature control for LED(Light Emitting Diode) lamp using a cooling fan is studied. An efficient temperature control scheme for the LED lamp using the fan wind at the lowest sound noise is studied. Also, for minimization study of sound noise and temperature control of an LED lamp, a sequential control algorithm using the cooling fan at the lowest sound noise is presented. For the study, after measurement of the minimum sound noise of the fan and related temperature of the LED lamp through tests, experiments on temperature control of the LED lamp using the fan was performed.