• Journal of Industrial Technology
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• v.20 no.A
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• pp.295-301
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• 2000

Various nondestructive prospecting method were applied to detect the flaws of concrete structure, but the satisfactory result could not be obtained, yet. Fracture and cavities existing concrete structure will have a bad effect on physical and mechanical characteristic of concrete. This study deal with detection of flaws using seismic first arrival and various inversion method in theoretical model. And ultrasonic seismic method is tried to experimental model to detect fracture and cavity.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.114-119
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• 1991

An input estimation technique for tracking filter(CHP algorithm) suggested by Y.T. Chan et. al. has bad performance for low maneuvering targets. In this paper, two maneuver detection algorithms are applied to Singer's target model. First, an CHP input estimation technique is applied to 9 state target model. Second, we construct a maneuver detection and correction technique using pseudo acceleration measurements, which are derived directly from measurements. These two filters have good performance for even the low maneuvering targets.

• Convergence Security Journal
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• v.23 no.2
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• pp.85-94
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• 2023

In the face of the serious security situation with the increasing threat from North Korea, Korean Army is pursuing a reduction in troops through the performance improvement project of the GOP science-based border security system, which utilizes advanced technology. In order for the GOP science-based border security system to be an effective alternative to the decrease in military resources due to the population decline, it must guarantee a high detection and identification rate and minimize troop intervention by dramatically improving the false detection rate. Recently introduced in Korean Army, the GOP science-based border security system is known to ensure a relatively high detection and identification rate in good weather conditions, but its performance in harsh weather conditions such as rain and fog is somewhat lacking. As an alternative to overcoming this, a radar-based border security system that can detect objects even in bad weather has been proposed. This paper proves the effectiveness of the AI-based scientific border security system based on radar that is being currently tested at the 00th Division through the 2021 Rapid Acquisition Program, and suggests the direction of development for the GOP scientific border security system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.12
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• pp.2300-2307
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• 2008

This study receives the noise transmitted in a constant audio frequency range through a microphone array in which the noise(like grease in a pan) occurs on the power supply line due to the troublesome partial discharge(arc). Then by going through a series of signal processing of removing noise, this study measures the distance and direction up to the noise caused by the troublesome partial discharge(arc) and monitors the result by displaying in the analog and digital method. After these, it determines the state of each size and judges the distance and direction of problematic part. When the signal sound transmitted by the signal source of bad insulator is received on each microphone, the signal comes only in the frequency range of 20 kHz by passing through the circuit of amplification and 6th low pass filter. Then, this signal is entered in a digital value of digital signal processing(TMS320F2812) through the 16-bit A/D conversion. By doing so, the sound distance, direction and coordinate of bad insulator can be detected by realizing the correlation method of detecting the arriving time difference occurring on each microphone and the algorithm of detecting maximum time difference.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.11
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• pp.1131-1135
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• 2014

This paper proposes the enhanced faulty node detection scheme with hybrid algorithm using Markov-chain model on BCH (Bose-Chaudhuri-Hocquenghem) code in naval distributed control networked systems. The probabilistic model-driven approach, on Markov-chain model, in this paper uses the faulty weighting interval factors, which are based on the BCH code. In this scheme, the master node examines each slave-nodes continuously using three defined states : Good, Warning, Bad-state. These states change using the probabilistic calculation method. This method can improve the performance of detecting the faulty state node more efficiently. Simulation results show that the proposed method can improve the accuracy in faulty node detection scheme for real-time naval distributed control networked systems.

• Journal of the Optical Society of Korea
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• v.17 no.6
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• pp.513-517
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• 2013

Recently, maskless lithography (ML) systems have become popular in digital manufacturing technologies. To achieve high-throughput manufacturing processes, digital micromirror devices (DMD) in ML systems must be driven to their operational limits, often in harsh conditions. We propose an instrument and algorithm to detect DMD malfunctions to ensure perfect mask image transfer to the photoresist in ML systems. DMD malfunctions are caused by either bad DMD pixels or data transfer errors. We detect bad DMD pixels with $20{\times}20$ pixel by white and black image tests. To analyze data transfer errors at high frame rates, we monitor changes in the frame rate of a target DMD pixel driven by the input data with a set frame rate of up to 28000 frames per second (fps). For our data transfer error detection method, we verified that there are no data transfer errors in the test by confirming the agreement between the input frame rate and the output frame rate within the measurement accuracy of 1 fps.

• Proceedings of the KIEE Conference
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• 1995.07a
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• pp.65-67
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• 1995

The squirrel cage rotors for induction motors may have several faults such as broken bars, bad spots in end ring, abnormal skew caused by improper processing. These faults have bad effect on the performance of the induction motor. This paper proposes the detecting technique of these faults by analyzing the current of the detecting electric magnet, using 2-D finite element method taking account of the rotor movement.

• Proceedings of the KIEE Conference
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• 2001.05a
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• pp.313-315
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• 2001

The power system automation, especially the substation automation is a major issue. so it has been widely studied each country in the world. Since the substation system includes lots of measuring devices. a lot of data and system information are transmitted to operators. The measured values usually have the error that results from the communication process, and it can degrade the reliability of estimated values. So. the detection and correction of measured values at a substation are important factors for substation automation. In this paper, we study the detection and col of measured values at the domestic 154kV/2 distribution substation of double bus structure study will be useful for expected economic dispatch measuring device's inspection and corr management by SCADA system operation, substation automation.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.531-535
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• 1999

Automatic human face detection in a complex background is one of the difficult problems. In this paper, we propose an effective and robust automatic face detection approach that can locate the face region in natural scene images when the system is used as a pre-processor of a face recognition system . We use two natural and powerful visual cues, the skin color and the eyes. In the first step of the proposed system, the method based on the human skin color space by selecting flesh tone regions using normalized r-g space in color images. In the next step, we extract eye features by calculating moments and using geometrical face model. Experimental results demonstrate that the approach can efficiently detect human faces and satisfactory deal with the problems caused by bad lighting condition, skew face orientation.

• Journal of the Korean Society of Industry Convergence
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• v.6 no.4
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• pp.325-331
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• 2003

This paper described the characteristics of the exhaust pressure and proposed the assistant device for detection of misfired cylinder. Misfire, one of abnormal combustion, affects a bad influence of the 3-way catalyst and emits unburned hydrocarbon. Therefore, to prevent these unusual phenomena and eliminate the factor of the environmental pollution, early detection and correction of the misfired cylinder play a very important role. The configuration of assistant device was changed by length and diameter of pipe and analyzed with the install position on the exhaust system. Experimental results showed that the configuration of assistant device is not affected more than length and diameter of pipe and the assistant device is be effective in the detection of misfired cylinder on the gasoline engine.