• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.2
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• pp.445-450
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• 2016

This paper studied on the influence of naval vessel shape on vertical magnetic field after the vessel was demagnetized. The triangular shape, the rectangular shape and circular shape were adaped from vessel's structual drawings. Magneto-static FEM analysis was performed to obtain the iduced magnetic field due to earth magnetic field for those shapes. During demagnetization process, magnetic field of residual magnetization was observed. The holizontal and vertical magnetic field were calculated depending on vertical bias magnetic field through magnetc component seperation. To demagnetize naval vessel ship, demagnetizing coils shoud be wound more finely in the vow and stern of the ship than it should be in the mid-part of the ship.

• Journal of the Korean Society for Nondestructive Testing
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• v.19 no.1
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• pp.8-15
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• 1999

In order to develop an effective way of measuring the mode I stress intensity factor, $K_I$, by the technique based on the alternating current potential drop (ACPD), the effect of the magnetic flux in the air on the change in potential drop due to load for both ferromagnetic and paramagnetic materials containing a two-dimensional surface crack was investigated. Additionally the effects of the demagnetization and the crack length on the change in potential drop were examined. In the case that the measuring system was designed to induce a large amount of electromotive force, the amount of the change in potential drop due to load was shown to increase largely Also the relationship between the change in potential drop and that in $K_I$ was indicated to be linear without any treatment and it was shown that the demagnetization had almost no effect on the change in potential drop. The change in potential drop did not depend on the crack length but on the measuring system. For the application of the ACPD technique to determine $K_I$.

• Journal of KIISE:Software and Applications
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• v.37 no.10
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• pp.788-801
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• 2010

Advancing of mobile device is remarkable, so the research on mobile input device is getting more important issue. There are lots of input devices such as keypad, QWERTY keypad, touch and speech recognizer, but they are not as convenient as typical keyboard-based desktop input devices so input strings usually contain many typing errors. These input errors are not trouble with communication among person, but it has very critical problem with searching in database, such as dictionary and address book, we can not obtain correct results. Especially, Hangeul has more than 10,000 different characters because one Hangeul character is made by combination of consonants and vowels, frequency of error is higher than English. Generally, suffix tree is the most widely used data structure to deal with errors of query, but it is not enough for variety errors. In this paper, we propose fast approximate Korean word searching system, which allows variety typing errors. This system includes several algorithms for applying general approximate string searching to Hangeul. And we present profanity filters by using proposed system. This system filters over than 90% of coined profanities.