• KIEE International Transactions on Electrophysics and Applications
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• 제3C권3호
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• pp.91-98
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• 2003

The importance of improving the quality of electric power is being strongly raised, owing to an increasing use of sensitive and small-sized electronic devices and systems. The transient over-voltages on low-voltage power distribution systems are induced by direct or indirect lightning return strokes. These can cause damage and/or malfunction of the utility systems for home automation, office automation, factory automation, medical automation, etc. The behaviors of lightning overvoltages transferred through the transformer to the low-voltage distribution systems using a Marx generator were experimentally investigated. Furthermore, the coupling mechanisms of lightning overvoltages transferred to the low-voltage systems were clearly illustrated through a theoretical simulation using a Pspice program. The overvoltages in low-voltage ac power systems are rarely limited by the application of the surge arrester to the primary side of the distribution transformer. A superior surge protection scheme is to install surge protection devices at the service entrance switchboard and/or at the load devices in TN power systems.

• 센서학회지
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• 제27권1호
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• pp.59-63
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• 2018

Among Internet of things (IoT) applications, the most demanding requirements for the widespread realization of many IoT visions are security and low power. In terms of security, IoT applications include tasks that are rarely addressed before such as secure computation, trusted sensing, and communication, privacy, and so on. These tasks ask for new and better techniques for the protection of data, software, and hardware. An integral part of hardware cryptographic primitives are secret keys and unique IDs. Physical Unclonable Functions(PUF) are a unique class of circuits that leverage the inherent variations in manufacturing process to create unique, unclonable IDs and secret keys. In this paper, we propose a low power Arbiter PUF circuit with low error rate and high reliability compared with conventional arbiter PUFs. The proposed PUF utilizes a power gating structure to save the power consumption in sleep mode, and uses a razor flip-flop to increase reliability. PUF has been designed and implemented using a FPGA and a ASIC chip (a 0.35 um technology). Experimental results show that our proposed PUF solves the metastability problem and reduce the power consumption of PUF compared to the conventional Arbiter PUF. It is expected that the proposed PUF can be used in systems required low power consumption and high reliability such as low power encryption processors and low power biomedical systems.

• Nuclear Engineering and Technology
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• 제48권1호
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• pp.211-217
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• 2016

Most nuclear power plants now utilize solid grounded low voltage systems. For safety and reliability reasons, the low voltage (LV) high resistance grounding (HRG) system is also increasingly used in the pulp and paper, petroleum and chemical, and semiconductor industries. Fault detection is easiest and fastest with a solidly grounded system. However, a solidly grounded system has many limitations such as severe fault damage, poor reliability on essential circuits, and electrical noise caused by the high magnitude of ground fault currents. This paper will briefly address the strengths and weaknesses of LV grounding systems. An example of a low voltage HRG system in the LV system of a nuclear power plant will be presented. The HRG system is highly recommended for LV systems of nuclear power plants if sufficient considerations are provided to prevent nuisance tripping of ground fault relays and to avoid the deterioration of system reliability.

• KIEE International Transactions on Power Engineering
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• 제5A권2호
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• pp.97-102
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• 2005

Voltage sags are the most widespread quality issues affecting distribution systems. This paper describes in some detail the voltage sag characteristics due to different types and locations of fault in a practical low voltage power distribution system encountered in the UK. The results not only give utility engineers very useful information when identifying parts of the system most likely to pose problems for customer equipments, but also assist the facility personnel to make decisions on purchasing power quality mitigation equipment.

• 조명전기설비학회논문지
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• 제17권4호
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• pp.94-99
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• 2003

정밀하고 소형화된 전자기기 사용의 증가로 인한 전원공급의 질적 향상에 대한 필요성이 강하게 증가하고 있다. 저압전원 배전계통에서의 과도 과전압은 직격 또는 유도뢰에 의해 유도되어지고, 가정, 사무실, 공장 등의 자동화시스템이나 병원설비와 같은 중요한 시스템의 손상이나 고장의 원인이 되고 있다. 본 논문에서는 임펄스 발생기를 이용하여 배전용 변압기를 거쳐 저압 전원시스템으로 이행되는 뇌과전압의 양상에 대하여 실험적으로 조사하였다. 배전용 변압기의 1차측에 설치한 피뢰기와 수용가측 추가접지는 저압 전원시스템으로 이행되는 뇌서지전압의 제한에는 크게 기여하지 않았다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.677-681
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• 2004

This paper presents the design and implementation of a low-profile power supply developed for AC-PDP application systems. In the proposed power supply, planar magnetics and SMD devices are integrated into advanced power conversion techniques to implement a low-profile power supply applicable to most AC-PDP application systems. Engineering details on the design and fabrication of planar magnetic components are presented. The performance of the prototype power supply is also demonstrated to validate the application potentials of the proposed power supply.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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• pp.217-220
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• 2000

In this paper, A low-power MOS monolithic peak detector is presented. Designed for monolithic and low-power characteristics, this MOS peak detector can be integrated easily on the same chip as a module of large communication systems. The simulation results of this peak detector which was composed with four NMOSs and two capacitors show the power dissipation of 0.972㎽ and the good operations for 2㎓ operating pulse frequency. Therefore, it may be used as a functional block for various signal processing systems.

• 전기전자학회논문지
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• 제12권1호
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• pp.27-33
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• 2008

The demand of wireless communication is increased rapidly due to the development of wireless communication systems, and many people have the great interest about the "RF system". The trend of the RF audio system is to design the system with less power consumption. In this paper, we explain the Software Algorithm Design of RF systems that is suitable for low power consumption.

• Transactions on Electrical and Electronic Materials
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• 제17권6호
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• pp.317-328
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• 2016

Over the past few decades, CMOS current comparators have been used in a wide range of applications, including analogue circuits, MVL (multiple-valued logic) circuits, and various electronic products. A current comparator is generally used in an ADC (analog-to-digital) converter of sensors and similar devices, and several techniques and approaches have been implemented to design the current comparator to improve performance. To this end, this paper presents a bibliographical survey of recently-published research on different current comparator topologies for low-power and high-speed applications. Moreover, several aspects of the CMOS current comparator are discussed regarding the design implementation, parameters, and performance comparison in terms of the power dissipation and operational speed. This review will serve as a comparative study and reference for researchers working on CMOS current comparators in low-power and high-speed applications.

• ETRI Journal
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• 제43권3호
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• pp.459-470
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• 2021

This paper presents a low-cost prototype for monitoring online the maximum power produced by a domestic photovoltaic (PV) system using Internet of Things (IoT) technology. The most common tracking algorithms (P&O, InCond, HC, VSS InCond, and FL) were first simulated using MATLAB/Simulink and then implemented in a low-cost microcontroller (Arduino). The current, voltage, load current, load voltage, power at the maximum power point, duty cycle, module temperature, and in-plane solar irradiance are monitored. Using IoT technology, users can check in real time the change in power produced by their installation anywhere and anytime without additional effort or cost. The designed prototype is suitable for domestic PV applications, particularly at remote sites. It can also help users check online whether any abnormality has happened in their system based simply on the variation in the produced maximum power. Experimental results show that the system performs well. Moreover, the prototype is easy to implement, low in cost, saves time, and minimizes human effort. The developed monitoring system could be extended by integrating fault detection and diagnosis algorithms.