• Journal of KSNVE
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• v.4 no.3
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• pp.337-343
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• 1994

A method of the leak detection from the pipe system by using accelerometer is proposed. The signal detected from accelerometer is proved experimentally to be a dispersive wave. Based on the experiments, a method using the narrow band pass filter and the unit impulse response function is analyzed. The method uses the characteristics of the unit impulse response function, that the function is available evenin the narrow band signal because, unlike the cross correlation, it is normalized by the auto spectrum. The accelerometer is quite easier to use than the hydrophone in adapting to the pipe system.

• Proceedings of the KIEE Conference
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• 2007.11b
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• pp.75-77
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• 2007

Current percentage differential relaying has been recognized as the principal basis of main protection for stator windings of AC generator. The DWT has merit of obtaining frequency characteristics in time domain. In order to compensate for DFT's defects, we proposed fault detection algorithm using DWT. This paper describes a comparative analysis about conventional DFT-based DFR and advanced DWT-based relaying.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.6
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• pp.950-956
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• 2013

This paper describes a sensitivity-coefficient-based iterative method for detecting cracks in a structure. The sensitivity coefficients of a cracked structure are obtained by changing its eigenvectors. The proposed method is applied to a cracked cantilever. The crack is modeled as a rotational stiffness. The predicted cracks are in good agreement with those from a structural reanalysis of the cracked structure.

• Toxicological Research
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• v.25 no.4
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• pp.231-235
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• 2009

Trace lead detection for cyclic voltammetry (CV) and square-wave (SW) stripping voltammetry was performed using mercury immobilized onto a carbon nanotube electrode (HNPE). Using the characteristics of mercury and the catalytic carbon nanotube structure, a modified technique, the $0.45{\mu}g/l$ detection limit of lead ion was attained. The developed method can be applied to pond water, fish tissue, plant tissue, and in vivo direct assay.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2008.10a
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• pp.494-497
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• 2008

In Mobile ad hoc networks (MANET), nodes could transmit packets for each other to communicate beyond their transmission range without centralized control. Unlike infrastructure-based wireless networks, due to the unique characteristics of MANETs such as open network architecture, stringent resource constraints and highly dynamic network topology, networks are vulnerable to wormhole attacks launched through colluding nodes. In this paper, we develop an wormhole detection and prevention algorithm for MANET.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1997.10a
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• pp.267-270
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• 1997

As an approach to develope a control system with robustness in changing control environment conditions, this paper will propose a robot manipulator control system using multilayer neural network and immune algorithm. The proposed immune algorithm which has the characteristics of immune system such as distributed and anomaly detection, probabilistic detection, learning and memory, consists of the innate immune algorithm and the adaptive immune algorithm. We will demonstrate the effectiveness of the proposed control system with simulations of a 2-link robot manipulator.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.149-152
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• 2001

In this paper, a 1.5V 2㎓ low-power peak detector is presented. Analyzing the designed peak detector circuit which is composed with two NMOSs, two diodes, and two capacitors, the detection characteristic relationships are derived. The simulation results with SPICE for 2㎓ pulse signals and sinusoidal signals on the 1.5V supply voltages show the good detection characteristics for input signal levels of 50㎷~500㎷, and show very small power dissipation of 0.332㎽.

• Proceedings of the Optical Society of Korea Conference
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• 2007.07a
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• pp.347-348
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• 2007

We have implemented a hydrogen detection system based on a Pd coated fiber sensor. The configuration of the system and the characteristics of the hydrogen sensor was presented.

• Journal of Radiation Protection and Research
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• v.30 no.1
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• pp.27-30
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• 2005

New possibilities are discussed for cholesteric liquid crystals (CLC) as sensor materials for detection of ionizing radiation, biologically active UV radiation, and the presence of hazardous vapors in atmosphere. A distinguishing property of CLC-based detectors is their 'bioequivalence', i.e., mechanisms of their response to external factors essentially imitate the corresponding mechanisms of biological tissues. Such detectors can ensure sufficiently high sensitivity to make feasible their use as alarm indicators or in biophysical studies. Specific examples ate given of sensor compositions and their response characteristics.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.3
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• pp.161-165
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• 2004

In this paper, we have designed the ground faults detection and interrupting controller at normal condition of AC 120v to 240v rating voltage. Ground faults in electrical network have the characteristics of low current, 60㎐ frequency to 2㎑frequency. The load condition are no load and 20A load. The trip level of the controller is 6㎃ with ground faults. The Controller algorithm is implemented using pic16c71 microprocessor.