• Journal of Institute of Control, Robotics and Systems
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• v.9 no.8
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• pp.647-650
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• 2003

PLC (Power Line Communication) is the communication method using the existing power line installed in houses and offices to convert and transmit high frequency communication signal from tens of KHz to tens of MHz, and receive the filtered signal using high frequency filter The advantage of PLC is that PLC uses the existing power line installed in houses and offices so it does not require separate power line. Easy and convenient access using electric outlets is another advantage of PLC. However, PLC has some disadvantages such as limited transmission power, high load interference and noise, variable signal attenuation, characteristic of impedance, and selective possibility of frequency property. We designed the boiler temperature control system unit by using the PLC modem. We can avoid unnecessary heating of separate temperature control unit, and save the cost accordingly control stability of the proposed system is proven through the experiment.

• Journal of KSNVE
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• v.5 no.2
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• pp.169-181
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• 1995

A theoretical model has been studied to describe the sound radiation analysis for structural vibration noise control of tire under the action of random moving line forces. When a tire is analyzed, it has been modeled as a curved beam with distributed springs and dash-pots which represent the radial, tangential stiffness and damping of tire, respectively. The reaction due to fluid loading on the vibratory response of the curved beam is taken into account. The curved beam is assumed to occupy the plane y = 0 and to be axially infinite. The material of curved beam and elastic foundation are assumed to be lossless, and governed by the law of Bernoulli-Euler beam theory. The expression for sound power is integrated numerically and its results examined as a function of Mach number(M), wavenumber ratio(.gamma.) and stiffness factor(.PSI.). The experimental investigation for structural vibration noise of tire under the action of random moving line forces has been made. Based on the STSF(Spatial Transformation of Sound Field) techniques, the sound power and sound radiation are measured. The experimental results show that operating condition, material properties and design factors of the tire have a great effect on the sound power and sound radiation characteristics.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.33-38
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• 2007

This paper presents a experimental evidence of the generation of the earth potential and communication line noise from the electric railway. There is a critical measurement err in case of measuring the electrical power induced noise voltage and degree of cable balance in the field of earth potential generated. As a results, it has been found that the conventional cable has more noise immunity than shielded cable near the railway where the earth current flows through the sheath layer.

• Journal of Electrical Engineering and information Science
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• v.2 no.6
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• pp.116-122
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• 1997

The audible noise produced by corona discharge in high voltage transmission lines is the most important line design consideration. In this paper, more accurate and useful formulas for predicting the A-weighted audible noise during heavy and light rain in alternative current (AC) transmission lines are proposed through comparison with the existing formulas. The proposed formulas are developed by the applications of evolutionary computations (ECs) to audible noise data base from long-term measurement.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.28A no.5
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• pp.339-346
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• 1991

In this paper the performance of communication system in the electrical power line using error correcting codes is analysed. The BCH codes and interleaved code are to be used for correcting burst and random errors in the power line channels. The data rate of 2400 bps and the carrier frequency of 12KHz are assumed. Actual power line noise is recorded and simulated in the BPSK PLC system model.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.1
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• pp.37-42
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• 2000

The radio noise produced by corona discharge in high voltage transmission lines is one of the most important line design considerations. Therefore it is necessary for transmission line designers to pre-evaluate radio noise using prediction formulas or field test results. In this paper, more accurate and useful formulas for predicting radio noise during fair and foul weathers in high voltage AC transmission lines were proposed through comparison with the existing formulas. Also it was verified by comparing with the long-term measured data from operating lines that the proposed formulas are more accurate. The proposed prediction formulas are developed by the applications of nonlinear least squares optimization method to radio noise database collected from lines throughout the world.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1088-1090
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• 1999

The radio noise produced by corona discharge in high voltage transmission tines is one of the most important line design considerations. Therefore it is necessary to pre-evaluate radio noise for transmission line designers using Prediction formulas or field test results. In this Paper, more accurate and useful formulas for Predicting radio noise during fair and foul weathers in AC transmission lines were proposed through comparison with the existing formulas. Also it was verified by comparing with the long-term measured data from operating lines that the Proposed formulas are very accurate. The Proposed prediction formulas are developed by the applications of nonlinear least square optimization method to radio noise database collected from lines throughout the world.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.11
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• pp.1837-1843
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• 1997

This study experimentally demonstrates the use of active muffler attached to the automotive exhaust system to reduce exhaust noise. For improving the signal to noise ratio in the process of estimation of secondary path transfer functions, the on-line algorithm that conventional inverse modeling is combined with adaptive line enhancer is used as the control algorithm. Active muffler is designed that the primary noise and the control sound are propagated as a plane wave in the outlet. Therefore, the error microphone could be placed out of the tail pipe center of a high temperature and the radiation noise to the outside could be reduced in the whole area around the outlet. The control experiment for reducing exhaust noise with active muffler is implemented during run-up at no load. From the experimental results presented, compared with the conventional off-line method, the proposed on-line method is capable to acquire a reduction of exhaust noise above 5 dB in overall sound power level.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.4
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• pp.122-128
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• 2017

In order to simplify the wiring of construction heavy equipment, researches on PLC(Power Line Communication)-CAN(Controller Area Network) communication module are actively proceeding. Even if a PLC-CAN communication module is developed, a simulator capable of judging whether the PLC-CAN communication module is operating normally is needed. In this paper, we designed and developed a simulator that can measure the status of PLC-CAN communication module. We analyzed the characteristics of the power line communication frequency band by analyzing the characteristics of the power line and compared the noise characteristics with the passenger car in order to characterize the heavy equipment noise.

• Journal of IKEEE
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• v.13 no.2
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• pp.248-252
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• 2009

In this paper, analysis of a noise factor and an effective power strategy for the OLED dc-dc converter are described. One of the main reasons that one may not design the OLED power for dc-dc converter is that OLED's panel noise is composed of FFN(Frame Frequency Noise) and LFN(Line Frequency Noise). Into the bargain, FFN is caused by both the dc-dc (circuit) and driving circuit. It is hard to get rid of FFN, baeause FFN has very little results value for our ears. LFN is adjusted by analog compensation value. Actually, that is more important problem than FFN. It is known that voltage divider for OLED's mode variation is not good for compact power design. In the end, a circuit design for understanding OLED's noise and a novel muti-channel dc-dc converter were presented.