• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2570-2575
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• 2003

Monitoring a power transmission line is significant for power electric companies. In this paper, we propose a new method for detecting an fault point of power transmission line by use of M-sequence correlation technique. In this method, detecting signal is used as one or plural M-sequences ( same characteristic polynomial, including normal and reverse mark, synchronized ). In receiving point, we make same sequence with the input one and take crosscorrelation function between M-sequence and the received signal. We can see transfer fanctions of plural paths between inputs and a output taps separated from different of delay times on the crosscorrelation function, and from these transfer fanctions, so we compare them when fault occurred with in usual.

• Proceedings of the IEEK Conference
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• 2000.11d
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• pp.151-154
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• 2000

We propose a statically motivated scene change detection algorithm. As the difference between the neighboring frames will generate peaks at scene boundaries, the problem of detecting fast scene changes is equivalent to detecting peaks in a given sequence. In this paper, the peak detection is performed via several statistics, namely the sample means and variances. For eliminating flash lights as well as detecting fast scene changes within a small number of frames, we have opted to use a two-stage process for computing the necessary statistics. The results indicate superiority of necessary statistics. The results indicate superiority of the proposed algorithm over the previously reported algorithm.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.439-442
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• 2000

When we measure the acoustical properties of a room using multiple microphone system, it is important to grasp exact time delay of the early reflections from impulse response pair. But it is often very difficult to identify the early reflections in natural shape, because a waveform may be deformed due to the characteristics of a sound source loudspeaker, microphone and reflected wall and overlapping of plural waveform. In this paper to obtain more accurate and enough early reflections, we propose the brand-new five-channel sound receiving system and introduce peak-detecting algorithm. The system has microphones mounted at the origin and four points of a regular tetrahedron. The newly introduced peak-detecting algorithm can show exact peak position in each channel, in spite of deformation due to reflected walls, loudspeaker and microphone.

• Proceedings of the KIPE Conference
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• 2016.07a
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• pp.471-472
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• 2016

Since photovoltaic generating system is significantly important among renewable energy sources, photovoltaic plants are installed more than past. As a result, accidents of photovoltaic system are also increased, so the additional hardware which includes monitoring system and periodic inspection are required for safety. In addition, a photovoltaic system is installed where a person can't approach to detect a fault, so a number of devices are required to detect it. This paper proposes that drone and thermo-graphic camera are used for detecting a fault of photovoltaic plant and suggests efficiency to control a drone for detecting a photovoltaic plant.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.607-612
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• 2001

Based on the flow characteristics around a piercing cylinder, a free surface-flow velocitmetry which can be used in extremely harsh environment such as molten steel flow was developed. The velocimetry is consisted of finite length cylinder, load detecting elastic plate, electric signal transducer and data acquisition H/W and S/W. Using such a velocimetry, two velocity measurement schemes were established which one is flow resistance detecting scheme and the other is Karman Vortex frequency detecting scheme. For calibration of each scheme, realistic flow water model was used and in followings, detailed calibration processes were explained.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.300-302
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• 2002

In this paper the high-speed fault current detector for superconducting fault current limiter is described. Detecting and interrupting the fault currents as quickly as possible is required in order not to exceed the thermal capacity of superconducting fault current limiter. A detecting method of an instantaneous fault current magnitude is adopted in the equipment described in this paper and a current signal through an analog/digital(A/D) converter would be compared with the reference in the digital signal processor(DSP). Around 20ms has elapsed for detecting the fault current. It is necessary to establish the appropriate trade-off between the reliability and detection speed.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.474-477
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• 2005

Surface Plasmon Resonance(SPR) sensor system can be applicable for detecting of many biospecific interactions. In this study, the feasibility of the experimental $SPREETA^{TM}$ evaluation kit to analyze human IgG, Pseudomonas aeruginosa, was investigated. The sensor prepared for detecting of anti-human IgG has response on $0.1{\mu}{\ell}$ of the anti-human IgG solution. SPREETA was able to detect P. aeruginosa solution in the range above $10^8\;CFU/mL$ with the chitosan/ alginate multilayers.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.571-575
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• 2001

A protection scheme for hybrid active power filters, which is combined shunt passive filter and small rated series active filter, is presented and analyzed in this paper. The proposed series active power filter operated as a high impedance 'k($\Omega$)' to the fundamental component when over current occurs in the power distribution system, and three control strategies are proposed in this paper. The first is the method by detecting the fundamental source current through the p-q theory, the second is the method by detecting the fundamental component of load current in Synchronous Reference Frame (SRF) and the third is the method by detecting the input voltage. When the over current occurs in the power distribution system, the proposed scheme protects the series active power filter without additional protection circuits. The validity of proposed protection scheme is investigated through experimental result for the prototype hybrid active power filter system.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.1
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• pp.191-198
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• 2001

In order to comprise a basic closed-loop control system for hydraulic systems it is necessary to detect the piston rod stroke of a hydraulic cylinder. There are many conventional type sensors which can detect the displacement of cylinders. However, they cannot reveal the original performance normally or they cannot be applied at all where the operating circumstance of cylinders is beyond specifications of sensors. Especially, for the purpose of detecting the strokes of cylinders mounted on heavy equipments, a special exclusive sensor must be used because the operating circumstances of heavy equipments are so severe that general purpose sensors cannot endure such circumstance as shock and a residual vibration induced by rough works. In this paper, an exclusive method for detecting the piston rod stroke for heavy equipments is suggested, which adopts a remote detecting technique using optical fiber sensors. Several experiments using the prototype are executed for verifying the effectiveness of the suggested method and the possibility of the accurate detection of stroke.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.783-788
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• 2001

Voids created with concrete construction or deterioration result in serious weakness from the aspects of both structural and durable function. Ultrasonic method using image processing technique was used for detecting pattern of voids in concrete in this study Experimental investigation was carried out for three types(patterns) of void in concrete. The effect of curing period of concrete and ultrasonic measurement method was also investigated. As a result it has been verified that the semi-direct measurement method is more effective than the other methods for detecting pattern of voids in concrete in ultrasonic method using image processing technique. The longer the curing period of concrete is, the better the detection accuracy of void pattern can be obtained.