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Ionospheric Behaviors Over Korea Peninsula During the Super Geomagnetic Storm Using GPS Measurements (GPS 관측자료에 나타난 초대형 지자기 폭풍 기간 동안 한반도 상공 전리층 양상)

Chung, Jong-Kyun;Choi, Byung-Kyu;Baek, Jung-Ho;Jee, Geon-Hwa;Cho, Jung-Ho
- Journal of Astronomy and Space Sciences
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- v.26 no.4
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- pp.467-478
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- 2009
The super-geomagnetic storms called 2003 Halloween event globally occurred during the period of 29 through 31 which are the following days when the solar flares of X18 class exploded on 28 October 2003. The S4 index from GPS signal strength and the peak electron density ($NmF_2$) from GPS tomography method are analyzed according to the date. The occurrences of the cycle slip and scintillation in the GPS signals are 1,094 and 1,387 on 28 and 29 October, respectively and these values are higher than 604 and 897 on 30 and 31 October. These mean the ionospheric disturbances are not always generated by the period of geomagnetic storm. Therefore, GPS S4 index is useful to monitor the ionospheric disturbances. Behaviors of ionospheric electron density estimated from GPS tomography method are analyzed with the date. At UT = 18 hr, the maximum $NmF_2$ is shown on 28 October. It agrees with $NmF_2$ variation measured from Anyang ionosonde, and the GPS signal are better condition on 30 and 31 October than 28 October. In conclusion, GPS signal condition is relation with geomagnetic activities, and depend upon the variation of the electron density. We will study the long-term data to examine the relationship between the GPS signal quality and the electron density as the further works.
https://doi.org/10.5140/JASS.2009.26.4.467 인용 PDF KSCI

KCAB's Arbitration of U.S. Patent Exhaustion Disputes Over Artificial Intelligence and Internet of Things Technologies

Shin, Seungnam
- Journal of Arbitration Studies
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- v.28 no.3
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- pp.21-33
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- 2018
Technological innovations can be protected by patents, and patent applications are filed in various patent offices around the world including the United States Patent and Trademark Office (USPTO). Recently, the U.S. exportation of artificial intelligence and internet of things patents in the form of foreign sales of articles embodying U.S. patents and international technology licenses has grown substantially. However, due to the U.S. Supreme Court's Lexmark decision reconfirming an international patent exhaustion doctrine, the asian or korean importers importing such U.S. goods embodying U.S. patents do not have to worry about patent infringement liability, even when they try to resell the patented goods to the third parties. KCAB can play a substantial role in resolving such patent disputes due to qualified expert arbitrators and the International Rules of KCAB which ensure impartiality and independence of the arbitrators.
https://doi.org/10.16998/jas.2018.28.3.21 인용 PDF

The Study on Earlier Evaluation of Concrete Strength Using Ultra Sonic Velosity Method (초음파 시험에 의한 콘크리트의 조기 강도 판정에 관한 연구)

김화중;이도헌;윤상천;박정민;최신호
- Proceedings of the Korea Concrete Institute Conference
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- 1995.04a
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- pp.136-141
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- 1995
The early evaluation on strength of concrete is useful to achieve on quality control and improvement of properties of concrete. Especially, we could say that the confidence of construction is increased by the increase durability and safety building, due to early evaluation. In this study, was proposed to ultra-sonic pulse method as a early evaluation method for strength of concrete with main parameter, sush as W/C ratio and S/A ratio. The experiment results are summarized to follow as : $\circled1$ The ultra-sonic pulse was decreased as the increase of W/C ratio. $\circled2$ The maximum value for the ultra-sonic pulse velocity and compressive strength was presented in the case of 40% S/A ratio and these value was decreased as the change of S/A ratio over 40% $\circled1$ The relationship of the ultra-sonic pulse velocity and compressive strength on 28days according to the change of W/C and S/A ratio is to be: $F_{28} = -209193R^2 + 384417R - 1763441$(W/C Ratio) $F_{28} = 1726R^2 - 774R - 502 (S/A Ratio)
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