• Journal of Aquaculture
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• v.21 no.3
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• pp.146-156
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• 2008

Tributyltin chloride(TBTCl) was administered through discrete immersion(2 hr each) from the $18^{th}-25^{th}$ day after hatching(dph). At the doses of 1, 2, 4 and 8 ${\mu}g/L$, the immersion at 2 ${\mu}g/L$ ensured 93% masculinization and the highest survival of 75% after the treatment. TBTCl acted as a growth suppressant and the magnitude of its suppression was stronger in females. During the 300 day experiment, it postponed sexual maturity of females from 120$^{th}$ dph in the control to 240$^{th}$ dph in the females treated at 8 ${\mu}g/L$. It reduced spawning frequency(22-3 times) and cumulative fecundity(1,632-19 eggs) by reducing the number of vitellogenic eggs. In the treated males too, it reduced sperm motility(100-68 sec); consequently, fertilizability of the sperm cells drawn from these males was also reduced from 88 to 43%. Progeny testing showed that the cross between males treated at>2 ${\mu}g/L$ and normal females generated the presumed 'homogametic' males. Both the treated 'homogametic' and 'heterogametic' males could induce the females to spawn fewer eggs than that of the normal males. A normal female somehow deducted the differences between the control, treated and sex reversed males; it preferred a normal male over a treated one, and a treated one over the sex reversed male.

• Proceedings of the KWS Conference
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• 2009.11a
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• pp.95-95
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• 2009

Zinc coatings provide the most effective and economical way of protecting steel against corrosion. There are three types of galvanizing lines typically used in production line in galvanizing industries,Galvanize (GI) coating (Zn-0.1-0.3%Al), Galfan coating (Zn-5%Al), Galvalume(GL) coating (45%Zn-Al). In continuous Galvanizing lines, the immersed bath hardware (e.g. bearings, sink, stabilizer, and corrector rolls, and also support roll arms and snout tip) are subjected to corrosion and wear failure. Understanding the reaction of these materials with the molten Zn alloy is becomes scientific and commercial interest. To investigate the reaction with molten Zn alloys, static immersion test performed for 4, 8, 16, and 24 Hr. Two different baths used for the static immersion, which are molten Zn and molten Zn-55%Al. Microstructures characterization of each of the materials and intermetallic layer formed in the reaction zone was performed using optical microscope, SEM and EDS. The thickness of the reaction layer is examined using image analysis to determine the kinetics of the reaction. The phase dominated by two distinct phase which are eutectic carbide and matrix. The morphology of the intermetallic phase formed by molten Zn is discrete phase showing high dissolution of the material, and the intermetallic phase formed by Zn-55wt%Al is continuous. Aluminum reacts readily with the materials compare to Zinc, forming iron aluminide intermetallic layer ($Fe_2Al_5$) at the interface and leaving zinc behind.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.39 no.4
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• pp.429-441
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• 2002

This paper concerns extracting 3D motion information from a 3D input device in real time focused to enabling effective human-computer interaction. In particular, we develop a novel algorithm for extracting 6 degrees-of-freedom motion information from a 3D input device by employing an epipolar geometry of stereo camera, color, motion, and structure information, free from requiring the aid of camera calibration object. To extract 3D motion, we first determine the epipolar geometry of stereo camera by computing the perspective projection matrix and perspective distortion matrix. We then incorporate the proposed Motion Adaptive Weighted Unmatched Pixel Count algorithm performing color transformation, unmatched pixel counting, discrete Kalman filtering, and principal component analysis. The extracted 3D motion information can be applied to controlling virtual objects or aiding the navigation device that controls the viewpoint of a user in virtual reality setting. Since the stereo vision-based 3D input device is wireless, it provides users with a means for more natural and efficient interface, thus effectively realizing a feeling of immersion.