• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.217-218
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• 1998

We propose a new digital beamforming algorithm using an interpolation filter in ultrasonic imaging systems. We compared the performances of the proposed algorithm to those of the conventional digital bemforming algorisms, post-beamformer and phase rotation beamformer, by a computer simulation and experiments. The results show that the proposed algorithm has better performance than the others.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.963-969
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• 2010

The railway vehicle consists of wires, bodies, bogies and wheelsets, and each part has very complex mechanism. In this paper, wheel-rail contact algorithm is implemented using C++ and inserted into the ODYN which is a dynamic analysis program. To analyze wheel-rail contact mechanism, information such as contact points, contact angle and rolling radius is calculated according to the wheel and rail profile. Using this information, a table for the calculation of the wheel-rail contact analysis is made according to the lateral displacement. And, the creepage and normal force are calculated and a creep force is estimated by the FASTSIM. To verify the reliability of the wheel-rail contact algorithm, results of the program are compared with the ADAMS/Rail and paper. Finally, a wheelset of the railway vehicle is modeled using ODYN and simulated static and dynamic analysis. And, to verify the reliability of the simulation results, a displacement, velocity, acceleration and force are compared with results of ADAMS/Rail.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.213-214
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• 1998

The important role of the ultrasonic Doppler system in the modem clinical medicine is to provide the clinical information of the vascular system. The ultrasonic pulsed wave(PW) Doppler system, a kind of the ultrasound Doppler system, is more available than the ultrasonic continuous wave(CW) Doppler system because it can evaluate the velocity and the direction of blood flow as well as the depth of vessel. However, the ultrasonic PW Doppler system has the disadvantage that the range of evaluating velocity of blood flow is limited(Nyquist limit). In order to solve this limit, we propose the algorithm for eliminating this aliasing in this paper. In addition, we propose the efficient signal processing algorithm.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1087-1092
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• 1990

This paper describes the development and control of a quadruped walking robot, named as KAISER-II. The control system with multiprocessor based hierachical structure is developed. In order to navigate autonomously on a rough terrain, an identification algorithm for robot's position is proposed using 3-D vision and guide-mark pattern Also, a simple attitude control algorithm is included using force sensors. Through experimental results, it is shown that the robot can not only walk statically on even terrain but also cross over or go through the artificially made obstacles such as stairs, horizontal bar and tunnel-typed one.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.5
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• pp.73-81
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• 1993

We have developed a system which can analyze the status of signal sent from/received to a signalling service equipment within the fully electronic switching system such as TDX-10. The system has such functions that acquire PCM signal of the preferred channel from the subhighway of the thirth-two channel by which a Universal Signal Tr ansceiver Unit(USTU) is connected with Time Switch Unit (TSU), and then classify the type of signal such as R2MFC/DTMF/CCT/VOICE, and determine the digit. Up to now, we have analyzed the frequency spec trum using the FFT. This paper describes the developement of PCM acquirer which can analyze the signal characteristics by acquiring the PCM signal in SHW(subhighway), and proposes the CZT(Chirp Z-Transform) algorithm. An algorithm which analyzes the acquired signal and determines the signal frequency and the corresponding power spectrum using the CZT is also discussed here.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.5
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• pp.529-535
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• 2009

This paper describes a measuring device of glass thickness using machine vision and image processing techniques on real-time. Today, the machine vision enable to inspect fast and exactly than human's eyes. The presented system has advantages of continuous measurement, flexibility and good accuracy. The system consists of a laser diode, a CCD camera with PC. The camera located on the opposite side of the incident beam measures the distance between two reflected laser beams from the glass top and bottom surface. We apply a binary algorithm to convert and analyze the image from camera to PC. Laser point coordination by border tracing algorithm is used to find the center of beam circle. The measured result was compared with micrometer and showed 0.002mm accuracy. Finally, the errors were discussed how to minimize the influence of glass wedge angle and angular error of moving stage.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.4
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• pp.152-159
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• 2005

The method of induction noise reduction can be classified by using passive control or active control method. However, the passive control method has a demerit to reduce the effect of noise reduction to low frequency (below) 500Hz) range and to be limited in a space of the engine room. Whereas, the active control method can overcome the demerit of passive control method. The algorithm of active control is mostly used in LMS (Least-Mean-Square) algorithm because it can obtain the complex transfer function easily in real-time. Especially, Filtered-X LMS (FXLMS) algorithm is applied to an ANC system. However, the convergence performance of LMS algorithm could not match if the FXLMS algorithm is applied to an active control of the induction noise under rapidly accelerated driving conditions. So, in order to solve the problem in this study, the Moving Bandpass Filter(MBPF) was proposed and implemented. The ANC using MBPF for the reduction of the induction noise shows that more noise reduction as 4dB than without MBPF.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.4
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• pp.81-90
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• 1996

In this paper, we implemented a computerized pulse diagnosis system for the developement of pulse diagnosis algorithms and the generalization of the pulse diagnosis. The system consists of the hardware and software. The hardware detects pulse waves and inputs the waves into the computer system, while the software not only manages and analyzes the input pulse wave data but also privides the database. In order to clinically test the developed pulse diagnosis system, we applied the carotid-radial pulse diagnosis algorithm to the system. As the results, it is found that the genralizatio of the pulse diagnosis is possible.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.237-239
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• 2009

The purpose of this research is to propose a system to detect a strip defect on a iron plate using an image processing, one way of finding defects on an iron plate. An existing way of image processing is using a light source which release a light energy in a certain frequency and a light absorbing display which responds to the light source. This research attempts to detect defects by using the image processing which handles an illumination, without depending on characteristics of light frequency. One of the advantages of this method is that it makes up for the weakness of the existing method which was too difficult for users to notice a defect. Also this method makes it possible to realize a real-time monitoring on a plate of iron.

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.471-474
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• 1990

In this paper, a vision-based inspection algorithm for checking mark quality on an integrated chip(IC) is proposed. In order to reduce the processing time for inspection, we are implemented image arithmetic unit and binary image projection processor in hardware. By adopting the hardwares, the processing time becomes less one sixth of that in case of using software only.