• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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• pp.1054-1057
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• 1993

A direct method of fuzzy inference and a fuzzy algorithm with learning function are applied to the steam generator level control of nuclear power plant. The fuzzy controller by use of direct inference can control the steam generator in the entire range of power level. There is a little long response time of fuzzy direct inference controller at low power level. The rule base of fuzzy controller with learning function is divided into two parts. One part of the rule base is provided to level control of steam generator at low power level (0%∼30% of full power). Response time of steam generator level control at low power level with this rule base is shown generator level control at low power level with this rule base is shown to be shorter than that of fuzzy controller with direct inference.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.601-604
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• 1996

It is well known that steam generator water level control at low power operation has many difficulties in a PWR (pressurized water reactor) nuclear power plant. The reverse process responses known as shrink and swell effects make it difficult to control the steam generator water level at low power. A new automatic control logic to remove the reverse process responses is proposed in this paper. It is implemented in PLC (programmable logic controller) and evaluated by using test equipment in Korea Atomic Energy Research Institute. The simulation test shows that the performance requirements is met at low power (below 15%). The water level control by new control logic is stabilized within 1% fluctuation from setpoint, while the water level by YGN 3 and 4 control logic is unstable with the periodic fluctuation of 25% magnitude at 5% power.

• International journal of advanced smart convergence
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• 제12권4호
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• pp.370-377
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• 2023

Previous research has demonstrated that happy moods are known to promote feeling-based processing, whereas sad moods promote reason-based processing. The current research investigates a boundary condition for the effects of a happy mood on feeling-based decision making. This research proposes that the level of control (low vs. high) one exercises in a happy situation can promote a greater reliance on feelings (vs. reasons) in making judgments and decisions. Specifically, we hypothesize that (1) a happy individual in a situation where control level is low (vs. high) will be more likely to choose a cognitively (vs. affectively) superior option (hypothesis 1), and (2) a happy individual in a situation where control level is low (vs. high) will exert reason- (vs. feeling-) based processing (hypothesis 2). Consistent with the hypothesis 1, the results of two experiments show that happy individuals are more likely to choose cognitively versus affectively superior options in a situation where control level is low (vs. high). Moreover, the mediation analysis confirms that happy individuals are more likely to rely on cognitive, reason-based decision making when their control level is low, which supports the hypothesis 2.

• Journal of Electrical Engineering and Technology
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• 제10권1호
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• pp.280-287
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• 2015

Three-level PWM rectifiers applied in medium voltage applications usually operate at low switching frequency to keep the dynamic losses under permitted level. However, low switching frequency brings a heavy cross-coupling between the current components $i_d$ and $i_q$ with a poor dynamic system performance and a harmonic distortion in the grid-connecting current. To overcome these problems, a mathematical model based on complex variables of the three-level voltage source PWM rectifier is firstly established, and the reasons of above issues resulted from low switching frequency have been analyzed using modern control theory. Then, a novel control strategy suitable for the current decoupling control based on the complex variables for $i_d$ and $i_q$ is designed here. The comparisons between this kind of control strategy and the normal PI method have been carried out. MATLAB and experimental results are given in detail.

• Journal of Mechanical Science and Technology
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• 제14권6호
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• pp.645-654
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• 2000

In this paper, low level control algorithms of a metal belt CVT are suggested. A feedforward PID control algorithm is adopted for line pressure based on a steady state relationship between the input duty and the line pressure. Experimental results show that feedforward PID control of the line pressure guarantees a fast response while reducing the pressure undershoot which may result in belt slip. For ratio control, a fuzzy logic is suggested by considering the CVT shift dynamics and on-off characteristics of the ratio control valve. It is found from experimental results that a desired speed ratio can be achieved at steady state in spite of the fluctuating primary pressure. It is expected that the low level control algorithms for the line pressure and speed ratio suggested in this study can be implemented in a prototype CVT.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1039-1043
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• 2005

Despite the many significant advances made in robot architecture, the basic approaches are deliberative and reactive methods. They are quite different in recognizing outer environment and inner operating mechanism. For this reason, they have almost opposite characteristics. Later, researchers integrate these two approaches into hybrid architecture. In such architecture, Reactive module also called low-level motion control module have advantage in real-time reacting and sensing outer environment; Deliberative module also called high-level task planning module is good at planning task using world knowledge, reasoning and intelligent computing. This paper presents a framework of the integrated planning and control for mobile robot navigation. Unlike the existing hybrid architecture, it learns topological map from the world map by using MST (Minimum Spanning Tree)-based SOFM (Self-Organizing Feature Map) algorithm. High-level planning module plans simple tasks to low-level control module and low-level control module feedbacks the environment information to high-level planning module. This method allows for a tight integration between high-level and low-level modules, which provide real-time performance and strong adaptability and reactivity to outer environment and its unforeseen changes. This proposed framework is verified by simulation.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.301-304
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• 1997

Two options arising during implementation of an advanced model-based control system on a process with low-level loops are discussed. Strengths and deficiencies of the options are examined and methods to overcome the deficiencies are proposed. Simulation results of a CSTR and distillation column are presented to demonstrate the performance improvements.

• Journal of Plant Biology
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• 제12권3호
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• pp.15-25
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• 1969

To investigate the radiation effect of P-32 on the soybean plants, the seeds treated with various levels of P-32 solution were sown and cultured in the pots. The growth of the plants and the contents of the macroelements were observed and the following results were obtained. 1) The linear growth of the plants at the early stage seemed to have been promoted by the low-level P-32 treatemnt. At the later growing stage, however, this difference among treatments were less conspicuous. 2) The plants of high level P-32 application showed some growth damaging symptom at the early growing stage. Later this damage was recorded as the time went on and these plants showed even better growth than the control. As a result at the late growing stage, they ensued highest growth. 3) The plants showed in general more growth at the low activity level than at the high-level at the early growing stage. At the late stage, however, the high-level activity promoted more growth than the low-level. 4) At the early growing stage P-32 treatment produced in general significantly more lower than control. At the later stage, however, this difference was not clearly seen. 5) The P-32 treatment seemed to have stimulated earlier florescence and this tendency was more clearly observable eapecially at the high activity level. 6) The weight of the air-dried seeds tended to be increased through P-32 treatment by 10-45%. This tendency was clearly observed especially at the low-level activity. 7) As for the contents of the various macroelements in the leaves, the nitrogen showed significantly larger contents at the middle level(S1) P-32 treatments. The phosphorous contents showed also highest at the middle levels activity and lower both at the high and low-activity levels. The potassium contents was proved, on the contrary, higher at the low-level activity and lower at the high-level. 8) The nitrogen contents in the stems was found significantly higher than control, except at the low-activity level. The phosphorous showed higher contents at the low-activity level and no significant difference at the high-activity level. As for the contents of potassium, calcium and magnesium, three seemed no significant difference among treatments. However, the magnesium showed somewhat higher content at the low-activity level, whereas the calcium was proved high than control. 9) The inorganic contents in the root showed that N and P in the P-32 treated plant were significantly higher than the control and the K-contents was, on the contrary, significantly higher at the control than the rest of the treatments. As for the calcium and magnesium there showed no difference among all treatments.

• 한국게임학회 논문지
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• 제13권2호
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• pp.131-142
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• 2013

게임중독은 자기통제 상실의 현대적 지표로서 동료관계 및 교우관계와 같은 사회적 관계맺음을 포함한 개인의 일상 전반에 부정적인 영향을 미치고 있다. 본 연구에서는 게임이용자들의 자기통제수준과 해석수준에 따라 게임중독수준의 차이를 살펴보았으며, 또한 자기통제수준과 해석수준의 상호작용이 게임중독에 어떠한 영향을 미치는지를 함께 탐색해보았다. 이를 위해, 게임이용자를 대상으로 온라인 서베이를 실시하였고, 총 918의 응답자를 분석대상으로 선정하였다. 연구결과, 낮은 자기통제수준과 낮은 해석수준을 가진 이용자들의 경우, 상대적으로 높은 자기통제수준 및 높은 해석수준을 가지는 경우에 비해, 더욱 높은 수준의 게임중독을 나타냈다. 또한 자기통제수준이 높을 경우에는 해석수준에 관계없이 게임중독수준이 낮았으나, 자기통제수준이 낮은 경우, 해석수준이 높고 낮음에 따라 게임중독에 미치는 영향일 달라짐을 확인할 수 있었다. 이는 해석수준이 하나의 조절변수로 기능하고 있음을 알려주는 결과로, 이러한 결과를 통해 개인의 자기통제와 해석수준의 변화를 통해 자율적인 규제를 통한 게임중독완화의 가능성을 논의해 볼 수 있다.

• 가정과삶의질연구
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• 제27권5호
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• pp.123-135
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• 2009

The purpose of this study was to investigate the effects of family conflict and self-control on school maladjustments of early adolescents. Subjects of this study consisted 662 middle school students drawn from 4 middle schools in Cheong-ju city. The results of this study were as follows: First, younger students' maladjustment to teachers was influenced by variables such as school year, economic levels, conflict strength between parents, conflict settlement between parents, reliability between parents and children, communication between parents and children and self-control, etc. In other words, students' maladjustment to teachers was high at the students in the 2nd year rather than in the 1st year, low economic level, high conflict strength between parents that younger students perceived, low conflict settlement between parents, low reliability between parents and children, high hostility between parents and children and low self-control. Second, younger students' maladjustment to the class was influenced by variables such as gender, school year, economic levels, conflict strength between parents, reliability between parents and children, communication between parents and children, and self-control, etc. In other words, young students' maladjustment to the class was high at the 2nd year students rather than at the 1st year students, low economic level, high conflict strength between parents, low reliability between parents and children, poor communication between parents and children, and low self-control. Third, younger students' maladjustment to rules was influenced by variables such as school year, economic level, conflict level between parents, hostility between parents and children, and self-control, etc. In other words, younger students' maladjustment to rules was high at the 1st year students rather than the 2nd year students of middle school, low economic level, high conflict strength between parents, high hospitality between parents and children and low self-control, etc. Fourth, younger students' maladjustment to friends was influenced by variables such as conflict strength between parents, conflict settlement between parents, hospitality between parents and children, and self-control, etc. In other words, younger students' maladjustment to friends was high at high conflict strength between parents, low conflict settlement between parents, high hospitality between parents and children and low self-control, etc. In the study, self-control was found to be the most important variable at younger students' maladjustment to teachers, class and rules, etc, and conflict settlement between parents was found to be the most significant variable at younger students' maladjustment to friends.