• 공학교육연구
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• 제18권5호
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• pp.59-66
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• 2015

In the on-line pre-learning which is applied in this study, on line pre-learning, in-class, post-learning are circulated together in the same experiments. The on-line pre-learning has been tried to 136 students in A junior college in Seoul for 3 years. The effects of their self-regulated learning are as follows. First, the self-regulated learning ability has increased by 0.42 point. The point after the self-regulated learning and before it is 3.24 and 3.66 respectively. Second, cognitive regulation, motivational regulation and behavioral regulation have also increased. Out of them, cognitive control has increased the most. Metacognitive strategy is higher than cognitive strategy. In conclusion, the result shows that the on-line pre-learning is helpful to develop the self-regulated learning ability and it is also suitable to teaching-learning method for junior college.

• 대한전기학회논문지
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• 제31권7호
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• pp.11-17
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• 1982

In this paper, a reliable and convenient evaluation method for the adequacy of any radial distribution line's voltage drop is proposed for improvement of the voltage regulation of the distribution line under operation. Using the voltage measurement of the first load branch point and the last point on the given distribution line its average line voltage drop and the line voltage drop variance by pure load variation are computed. And by these values and allowable or required line drop from proper voltage regulation view point, present adequency index and operation improvement index of the line drop are newly introduced for the evaluation of the given distribution line's voltage regulation. As a result of application to the 4 cases of study, the proposed method is proved to be reliable and convenient.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1014-1022
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• 2011

Urban transit operation is to manipulate the vehicle or train of urban transit to be operated on the basis of the installations such as track, power, communication, signaling and so on. It can be performed by manual or automated, or manned or manless operation considering its system built, operation efficiency, safety, etc. Because of the heavy impact directly to the safety of passenger transport, it has been managed strictly by the Regulation for Train Operation of Urban Transit according to Urban Transit Act. However, the present regulation has been basis of the manual operation mainly, it is crossing beyond the limitation of application to the manless operation which is being introduced moment to moment. It is needed increasingly to revise the regulation for the manless operation which is close at hand now. In this paper, we examined and analysed the cases of manless operation of urban transit planed within the country such as Busan 4th Line, Shinbundang Line, Busan-Kimhae Line, etc. based on the present regulation, and proposed the review of considerations to reflec the manless operation to the regulation to be revised.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 추계학술대회
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• pp.1071-1074
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• 2015

전력선통신 위해방지 기술기준은 전력선통신 장치가 인체나 다른 설비에 위해를 주지 않도록 준수해야 할 기술적 사항을 규정하고 있다. 전력선통신 위해방지 기술기준은 내용면에서 선로설비 설치에 대한 기술기준과 통합 운영하는 것이 효율적이다. 본 논문에서는 국내 전력선통신의 기술적 배경과 기술기준 개편방향에 대해 같이 논하기로 한다.

• 전기학회논문지P
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• 제60권3호
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• pp.126-132
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• 2011

A conventional LDO(Low Dropout Regulator) uses one OPAMP and one signal path. This means that OPAMP's DC Gain and Bandwidth can't optimize simultaneously within usable power. This also appears that regulation property and settling time of LDO can't improve at the same time. Based on this idea, a proposed LDO uses two OPAMP and has two signal path. To improve regulation property, OPAMP where is used in the path which qualities DC gain on a large scale, bandwidth designed narrowly. To improve settling time, OPAMP where is used in the path which qualities DC gain small, bandwidth designed widely. A designed LDO used 0.5um 1P2M process and provided 200mA of output current. A line regulation and load regulation is 12.6mV/V, 0.25mV/mA, respectively. And measured settling time is 1.5us in 5V supply voltage.

• 보건행정학회지
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• 제12권2호
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• pp.92-114
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• 2002

While making a vigorous discussion about self-regulation for exponential growth of harmful health information on the Internet, many countries lave made various efforts to select and circulate high quality health information on the Internet. The purpose of this study Is to review the serf-regulation methods of health information on the Internet and to suggest quality control methods of health information on the Internet suitable for Korea. Self-regulation methods of the health information on the Internet include ‘content rating system(or content selection system)’, ‘codes of conduct or guideline’, ‘internet hot-line’, ‘education for information providers and consumers’. Any self-regulation method should be used with other methods. We can regulate health information on the Internet effectively by using both self-regulation methods and compulsive methods such as law. Also information providers, information consumers, specialists, consumer representatives, scholars, governments officers should take part in doing these efforts and make concern.

• Journal of Electrical Engineering and Technology
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• 제8권4호
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• pp.712-718
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• 2013

With the development of industry and the improvement of living standards, better quality in power electric service is required more than ever before. This paper deals with the optimal algorithms for voltage regulation in the case where Distributed Storage and Generation (DSG) systems are operated in distribution systems. It is very difficult to handle the interconnection issues for proper voltage managements, because the randomness of the load variations and the irregular operation of DSG should be considered. This paper proposes the optimal on-line real time voltage regulation methods in power distribution systems interconnected with the DSG systems. In order to deliver suitable voltage to as many customers as possible, the optimal sending voltage should be decided by the effective voltage regulation method by using artificial neural networks to consider the rapid load variation and random operation characteristics of DSG systems. The simulation results from a case study show that the proposed method can be a practical tool for the voltage regulation in distribution systems including many DSG systems.

• 대한전기학회논문지:전력기술부문A
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• 제48권6호
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• pp.699-703
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• 1999

It is known that the LDC(Line-Drop Compensator) becomes to lose the function of proper voltage regulation for its load currents due to the real and reactive power generated by DGS(Dispersed Generation System), when DGS is introduced into the power distribution system of which the voltage is controlled by LDC. Therefore, in that case, it is very difficult to regulate the distribution line voltage properly by using LDC. One possible solution for this problem is the real-time voltage regulation method which is to optimally regulate the sending-end voltage in real-time by collecting the real-time load data of each load data of each load section between measuring points and by calculating the optimal seding-end voltage value from them. For this, we must know the real-time load data of each load section. In this paper, a modeling method of representing a load section on high voltage line with DGSs as an equivalent lumped load is proposed for gaining the real-time load data. In addition a method of locating the measuring points is proposed. Then, these proposed methods are evaluated through computer simulations.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.333-337
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• 1999

This paper presents the DQ transfomation space space vector modulation method to devel control algorithm of distribu STATCON(STATic CONdenser) for line volt regulation, dc link voltage regulation harmonics compensation. The Performance an of a PI with ramp comparision and synchro reference frame current controller is carried Based on these analysis, the control perform are desirable to compensate the harmonics a regulate dc link and line voltage of Distrib line.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.250-252
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• 1997

This paper deals with voltage regulation at the power Distribution system interconnected with DSG. Modern distribution substation adopt LDC method as the voltage regulation method to deliver suitable voltages to many customers. However, the operations of DSG interconnected with distribution system, the customers' voltage violate the permissible voltage limits. Therefore, to deliver suitable voltage to many customers at the distribution substation, an advanced voltage regulation method is required. In this paper, the on line realtime MLDC (Multiple Line Drop compensation) method, considered daedband and hysterical tap changing of the ULTC, is proposed. The result from a simulation study shows that the proposed method can be practical applications for the voltage regulation at the distribution system interconnected with DSG and unbalanced load pattern among feeders.