• Water for future
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• v.22 no.4
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• pp.441-451
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• 1989

Using the wave data by typhoons LEE, VERA, THELMA which gave great damages in the Korean penisula, the significant waves based on zero-up & down crossing and Tucker-Draper method are compared with those from the wave energy spectrum. And the histograms of individual waves obtained from zero-up crossing method are presented and compared with the Rayleigh, Weibull, Gluhovski, Ibrageemov and Goda distributions, and also the Chi-square goodness of fit test is applied to each theoretical distributions. It is shown that the significant wave heights by zero-up crossing method are very well agreed to those by energy spectrum method. The wave heights are found to well follow the Rayleigh and Goda distributions by the Chi-square test.

• Kyungpook Mathematical Journal
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• v.56 no.4
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• pp.1247-1257
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• 2016

In this paper, we discuss the crossing change operation along exchangeable double curves of a surface-knot diagram. We show that under certain condition, a finite sequence of Roseman moves preserves the property of those exchangeable double curves. As an application for this result, we also define a numerical invariant for a set of surface-knots called du-exchangeable set.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.117-124
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• 2002

Fixed distance control system at the railway level crossing have some problem. The problem is especially serious for high speed or low speed train. Therefore present developed device is fixed time control system. But fixed time control system haven't indicate device when train reach at the railway level crossing on alarm. This paper' result in study for train reach spare time indicate device.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.11
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• pp.1782-1793
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• 1989

Stroke crossing number, syntactic pattern recognition procedure, top down recognition structure, and heuristic approach are studied for the Korean text recognition. We propose new algorithms: 1)Korean vowel seperation using limited scanning method in the Korean characters, 2) extracting strokes using stroke width method, 3) stroke crossing number and its properties, 4) average, standard deviation, and mode of stroke crossing number, and 5) classification and recognition methods of limited chinese character. These are studied with computer simuladtions and experiments.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.389-390
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• 2007

In this paper, we propose a modified watershed algorithm to obtain exact edge of region. The proposed method adjusts priority at zero-crossing point of gradient in order to make the point of region decision time postponed. We compare the proposed method with a previous method and prove that this method can extract more correct edge of region.

• Proceedings of the KSR Conference
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• 2002.10a
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• pp.566-573
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• 2002

In this paper, is propose to the object(human) dection method using geometrical structures and projection histograms in the image. The problem of existing methods for objects tracking of background subtracted is resulted from uncertainty at background unfixed. In this paper, two methods are applied to solve problem. This problems are proved by method. This problems is demonstrated by using this methods and applied to the train railroad crossing. Therefore, this paper aims that this contributes to improve the accident of the train railroad crossing.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1269-1274
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• 2011

To cut down the maintenance expenses at branch lines, the foreign developed countries have developed the low-cost signalling on low-density lines. These examples are FFB(FunkFahrBetrieb) Radio based train operation by German railways(Deutsche Bahn AG), ERTMS REGIONAL by Europe and LOCOPROL system using a GPS. Also, Korea is developing Information and Communication Technology based low-cost signalling on low-density lines. The characteristics of this system are directly controled switch and crossing by driver. For the purpose of this paper, we reviewed the business process for switch and crossing control. Specially, we compared and analysed both methods whether the driver takes control over the operation procedures of switch or the control message is carried by the command of the controller. And by utilizing the instrument of UML, I planned the switch according to the control authority and the operation procedures needed for the control of crossing.

• KIEAE Journal
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• v.7 no.2
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• pp.57-62
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• 2007

Recently Among indoor noises plumbing noise from supply and drain water pipe is being pointed out as a annoying noise following to floor impact noise, and it is increasing the rate to point the noise due to the following several reasons: water pressure, vibration by fabricated structures and direct noise propagation from upper floor through ceiling This study aims to analyse the characteristics of toilet stool plumbing noise in apartment bathroom which are generated by crossing plumbings and elbows. And it analyse the effect of noise reduction by soundproofing and insulations which are covered at crossing plumbings. And also analyse the characteristics of noise about a type of elbows, crossing plumbing and result of dB(A). At last it provide a fundamental data for the purpose of reduction of plumbing noise in apartment.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1544-1549
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• 2004

A new collision avoidance algorithm is presented for two mobile robots in narrow corridor environments. When two robots meet each other in a narrow corridor, one should yield the way to the other robot. To solve the problem arising in this situation, they exchange their path to get information about crossing-points to check avoidance conditions, which are necessary for choosing the robot to yield. The conditions are summarized as follows. 1) If one robot blocks the path to the closest crossing-point in front of the other robot. 2) If the closest crossing-point of each robot is the same point. 3) Which robot is closer to the closest crossing-point. In this paper, we propose a path planning algorithm for the robot which yield the way. Simulation results are presented to verify the feasibility of the proposed collision avoidance algorithm.

• Journal of the Korean Society of Systems Engineering
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• v.10 no.2
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• pp.15-20
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• 2014

The river crossing is a very challenging operational function for the ground wheeled vehicle. In this study, the typical hazardous elements were identified by analysing the functional flow of river crossing operation and the survey on the similar operational experiences in real fields. The identified hazardous elements were reviewed on the basis of ALARP concept and reduction approaches were recommended for limited cases.