• Journal of Korean Ophthalmic Optics Society
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• v.6 no.2
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• pp.71-75
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• 2001

In this paper, a three-dimensional measuring system of thermoluminescence(TL) spectra based on temperature, wavelength and luminescence intensity was introduced. The system was composed of a spectrometer, temperature control unit for thermal stimulation, photon detector and personal computer for control the entire system. Temperature control was achieved by using feedback to ensure a linear-rise in the sample temperature. Digital multimeter(KEITHLEY 195A) measures the electromotive force of Copper-Constantan thermocouple and then transmits the data to the computer through GPIB card. The computer converts this signal to temperature using electromotive force-temperature table in program, and then control the power supply through the D/A converter. The spectrometer(SPEX 1681) is controlled by CD-2A, which is controlled by the computer through RS-232 communication port. For measuring the luminescence intensity during the heating run, the electrometer(KEITHLEY 617) measures the anode current of photomultiplier tube(HAMAMATSU R928) and transmits the data to computer through the A/D converter. And, we measured and analyzed thermoluminescence of $CaSO_4$ : Dy, P using the system. The measuring range of thermoluminescence spectra was 300K-575K and 300~800 nm, $CaSO_4$ : Dy. P was fabricated by the Yamashita's method in Korea Atomic Energy Research Institute(KAERI) for radiation dosimeter. Thermoluminesce spectra of the $CaSO_4$ : Dy, P consist of two main peak at temperature of $205^{\circ}C$, wavelength 476 nm and 572 nm and with minor ones at 658 nm and 749 nm.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.6
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• pp.829-834
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• 2011

This paper introduces a new system which measures abrasion quantity of cylinder liners of large-scale marine diesel engines. The proposed system consists of three parts; measurement part where an LVDT, a temperature sensor, a camera and LED for lighting control are installed, monitoring part which accomplishes measurement command transmission and monitoring based on PC or notebook, and master control part which controls the measurement part and transfers measurement data to the monitoring part. The accuracy of the developed system is compared with that of an internal micrometer with 1/100 mm accuracy.

• The Transactions of the Korea Information Processing Society
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• v.1 no.3
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• pp.319-326
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• 1994

Automatic control has been for the most part applied to linear systems where ti can be approximately formalized. In case that it is not definitely established the mathematical modelling to control objects, it requires manual control strategies which put under the human rule. In this paper, it constructs an FLC (Fuzzy Logic Controller) in order to turn a hand control into an automatic control in the domain of swimming pool that has been almost absolutely dependant on a skilled worker's experience. Genetic algorithms upgrade the knowledge which is acquired from human expert, using by FLC, so as to maintain knowledge in the very optimal way. It also designs an algorithm that modifies the rule base and the membership function at the same time, and ultimately will show that it can get better result than human controllers.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.2
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• pp.72-78
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• 2022

A vacuum brazed cooling passage for an aircraft engine controller was designed. In order to predict the total pressure loss, which is the main design factor of the cooling passage, theoretical and numerical methods for the major loss and the minor loss considering the overall shape of the cooling passage are presented. This design and evaluation method can predict the pressure loss of the complex cooling passage shape for various flow conditions at the initial design step.

• Proceedings of the KIPE Conference
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• 2007.11a
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• pp.184-186
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• 2007

본 논문에서는 소프트 스위칭 다상 부스트 컨버터 회로를 제안하였다. 태양의 일사량 및 주위온도 등에 의해 출력전압의 변동이 많은 태양전지로부터 정전압을 얻기 위해서 고효율의 전력변환 장치가 필요하다. 제안된 컨버터를 이용하여 동작 범위 내에서 변동하는 입력전압을 정출력전압으로 제어하고, 입력전류 리플과 출력전압 리플을 저감시킬 수 있다. 또한 ZVS, ZCS를 이용하여 스위칭 순간에 Turn-on, Turn-off 손실을 감소할 수 있다. 본 논문에서는 소프트 스위칭 다상 부스트 컨버터를 적용하여 시뮬레이션을 수행하였다.

• Journal of the Korea Concrete Institute
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• v.26 no.3
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• pp.287-297
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• 2014

Heat of hydration of mass concrete is one of the most important factors that significantly affect structural quality and construction period. Therefore, appropriate methods to control heat of hydration are essential technologies for mass concrete construction. In this study, probability of thermal cracking was checked by thermal analysis prior to the construction of a turbine foundation in a domestic power plant. Subsequently, changes of concrete mix proportion and an effective curing method were proposed to control heat of hydration of mass concrete structures. Concrete manufactured by slag cement was proposed instead of concrete produced by ordinary Portland cement, and an automated curing method was proposed to improve the curing method using typical moist curing with blanket. The automated curing method maintains the temperature difference between center and surface of concrete below a setting value by temperature monitoring. Concrete with slag cement was used for actual construction. One of two identical turbine foundations was cured by an insulated curing method, and the other was cured by the automated curing method to compare the curing methods. And then, the effects of control of heat of hydration were evaluated based on temperature/strain monitoring and crack investigations.

• Nuclear Engineering and Technology
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• v.26 no.3
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• pp.420-424
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• 1994

This paper presents an improved water level control scheme for Pressurized Water Reactor(PWR) Steam Generator(S/G) at the low power operation and transient states. To reduce fluctuations of the water level by the swell and shrink phenomena, the scheme adds feedforward terms considering S/G pressure and the feedwater temperature into the conventional proportional-integral feedback controller. The simulation results using the Compact Nuclear Simulator show that smaller level errors and much faster settling time than those of the conventional scheme can be obtained. The proposed algorithm is easily implementable and has a potential for the real applications.

• KSBB Journal
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• v.4 no.3
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• pp.208-214
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• 1989

The computer interfaced by the necessary hardwares and the software developed in PARTs I and II were used to control the fermentation with recombinant cells in an on-line feedback-feed-forward manner. The recombinant cells were induced for expression either thermally or chemically. Very accurate controls with fast response and no oscillation could be performed.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.491-491
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• 2012

External ballast capacitor를 이용하여 방전에너지를 제어하는 대기압 플라즈마 발생장치를 개발하였다. 기존은 대부분의 대기압 플라즈마 발생장치는 DBD를 이용하여 방전전류를 제어하였으나, 본 연구에서는 유전체를 없이 두 금속전극 사이에서 플라즈마를 발생시켰다. 외부에 연결된 External ballast capacitor에서 방전에너지가 전극 쪽으로 주입되도록 하였다. 따라서 capacitor의 용량과 인가전압에 따라 플라즈마의 방전에너지를 제어할 수 있다. 본 연구에서는 Optical Emission Spectroscopy와 ICCD Camera를 통하여 개발된 플라즈마 발생장치의 온도특성, 밀도와 같은 광학적 특성을 관찰하였으며, 아울러 전기적 특성도 함께 관찰하였다. 이 논문은 2011년도 정부(교육과학기술부)의 재원으로 한국연구재단의 기초연구사업 지원을 받아 수행된 것임(2011-0004827).

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1037-1038
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• 2006

CFL(Compact Fluorescent Lamp)는 기존에 사용되던 백열 램프를 바로 대치할 수 있고, 백열 전구에 비하여 광 효율이 우수하다는 장점으로 인해서 사용처가 점점 증가되고 있는 추세이다. 하지만 등기구가 가지는 공간적인 제약으로 인해서 EMI 필터와 PFC 회로를 내장할 수 없으며, 램프에서 발생한 열이 직접적으로 안정기 회로에 영향을 주어 안정기 내부 온도가 매우 높게 상승한다는 점으로 인해서 다양한 기능을 갖는 전용 ballast control IC를 사용할 수 없었다. 이러한 이유로 인해서 toroidal core를 이용한 자려식(self-excited) 동작 방법이 주로 이용되어왔다. 이러한 자려식 발진 방법은 설계하기가 까다롭기 때문에 램프 점등 전에 램프 필라멘트를 예열한 이후에 점등을 하는 rapid start 방법을 구현하기 어려웠다. 본 논문은 fairchild 반도체에서 만든 CFL 전용 ballast IC가 가지는 특성에 대해서 다루었다. IC 내부에 안정기 동작을 제어하기 위한 제어 부분과 두 개의 MOSFET를 내장하고 있어 안정기 구성에 필요한 공간을 최소화할 수 있고, 부하 상태를 검출하여 항상 Active ZVS 동작을 하도록 하는 기능을 내장하고 있어서 스위칭 손실을 최소화할 수 있다는 장점을 가지고 있다.