• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.1575-1578
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• 2008

네트워크가 광범위하게 발달함에 따라 DoS 공격 기법은 더욱 다양해지고 있고 지능화되고 있다. 따라서 네트워크에 기반한 DoS 공격의 탐지는 더욱 어려워지고 있다. 본 논문에서는 이러한 DoS 공격에 대해 호스트에 기반한 Native API 의 빈도수를 이용한 침입 탐지 메커니즘에 관하여 기술한다.

• Proceedings of the Materials Research Society of Korea Conference
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• 1993.05a
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• pp.89-90
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• 1993

• Proceedings of the Korean Information Science Society Conference
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• 2000.04a
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• pp.478-480
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• 2000

멀티캐스트 전송 필요성이 커지면서 보안에 대한 요구도 높아지게 되었다. 멀티캐스팅 라우터와 호스트간 그룹에 대한 정보를 관리하기 위해 사용되는 IGMP는 자체의 취약점이 있어서 DoS 공격이 가능하다. 본 논문에서는 이러한 IGMP 취약점과 예상되는 DoS 공격 유형을 살펴보고, 취약점 최소화를 위한 방법으로 트래픽 비율 제한 및 새로운 상태와 타이머 사용의 간단하면서도 효과적인 기법을 제안한다. 이를 위하여 라우터에 대한 하나의 상태와 네 가지의 타이머를 새로이 정의하고 동작 특성을 설명한다.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.33.3-34
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• 2020

The Milky Way (MW) and other systems including M31 and Cen A have flattened structures of their satellites (Disk of Satellites, DoS). Such structures are rare in simulations under the ΛCDM paradigm. DoS is known to depend mainly on 1) the alignment of satellite orbits and 2) the degree of central concentration of satellites. In this work, we examine quantitatively how these two parameters affect the flatness of a system. We find that the MW-like DoS is rare in IllustrisTNG100 simulation because its two parameters are out of the 1-s range and furthermore the MW has a structure more flattened than the other systems having similar parameters. Besides, we propose a new criterion for the MW-like systems superseding the conventional ones such as major-minor axis ratio of the MW's DoS with a value of 0.183. Each satellite system has a specific orbital combination and thus has a particular distribution of its parameters (and thus flatness). The median of the distribution is set as the representative value of each system. And the representative value of the MW can be used as a new criterion for classifying the MW-like DoS. We reconstruct the orbital combination of the observed MW satellites using GAIA DR2 data and find the systems in the simulation that have representative values similar to the new criterion from the reconstructed MW system. This allows us a new interpretation on the rarity of MW-like DoS in cosmological simulations.

• Korean Journal of Environmental Biology
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• v.20 no.1
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• pp.25-34
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• 2002

The halophytes were investigated on Gyeonggi Bay from Aug. 1999 to Oct. 2001. The survey was conducted at 38 areas including natural salt marshes, dunes, abandoned salt farms and bank areas. During this study 46 species of halophytes were collected in the areas. Among the halophytes the following 7 species were found at natural salt marshes only; Triglochin maritimum L, Carex scabrifolia Steud., Salicornia herbacea L., Suaedu australis (R. Br.) Moq., S. martima Dum., S. japonica Makino, S. malacosperma Hara, on the other hand 8 species at dunes only; Glehnia littoralis Fr. Schm., Cnidium japonicum Miq., Messerschmidia sibirica L., Ixeris repens A. Gray, Corispermum stauntonii Miq., Vitex rotundifolia L. fil., Ischaemum anthephoroides Miq., Carex kobomugi Ohwi. The distributions of halophytes in each regions are as the followings : Isl. Gyodong-do 21 species, Isl. Seokmo-do 10 species, Isl. Ganghwa-do 28 species, Isl. Jangbong-do 16 species, Isl. Sin & Si-do 10 species, Isl. Daemuui-do 23 species, Isl. Deokjeok-do 23 species, Isl. Ijak-do 10 species, Isl. Yeongheung-do 29 species, Soyra 25 species, Isl. Daebu-do 15 species, Ssangsong-ri 6 species, Hogok-ri 16 species, Maehyang-ri 10 species.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.4
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• pp.2196-2218
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• 2017

Multicast communication has been widely used in the Internet. However, multicast communication is vulnerable to DoS attack due to static router configuration. In this paper, HMC, a hopping multicast communication method based on SDN, is proposed to tackle this problem. HMC changes the multicast tree periodically and makes it difficult for the attackers to launch an accurate attack. It also decreases the probability of multicast communication being attacked by DoS and in the meanwhile, the QoS constrains are not violated. In this research, the routing problem of HMC is proven to be NP-complete and a heuristic algorithm is proposed to solve it. Experiments show that HMC has the ability to resist DoS attack on multicast route effectively. Theoretically, the multicast compromised probability can drop more than 0.6 when HMC is adopt. In addition, experiments demonstrate that HMC achieves shorter average multicast delay and better robustness compared with traditional method, and more importantly, it better defends DoS attack.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.1
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• pp.59-65
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• 2008

In security layer in the CDMA2000 1x EV-DO, a standard - C.S0024-a v2.0 is being accomplished under the project of 3GPP2(3rd Generation Partnership Project2). Therefore, a security device is needed to implement the security layer which is defined on the standard document for data transfer security between AT(Access Terminal) and AN(Access Network) on CDMA2000 1x EV-DO environment. This paper realizes the security layer system that can make safe and fast transfer of data between AT and AN. It could be applied to various platform environments by designing and implementing the Security Layer in the CDMA2000 1x EV-DO Security Layer to which applies C.S0024-A v2.0 of 3GPP2.

• Korean Journal of Environmental Agriculture
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• v.41 no.1
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• pp.16-23
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• 2022

BACKGROUND: Rice production by the current standard cultivation method is predicted to decrease due to global warming. It seems that there has been a strong warming trend in Hwaseong-si, Gyeonggi-do. This study attempted to understand the climate change in Hwaseongsi, Gyeonggi-do and to analyze the effect of climate change on rice production. METHODS AND RESULTS: The statistical and physicochemical analyses were performed using the rice cultivar 'Chucheongbyeo' yields grown at the rice paddy field plot in the Gyeonggi-do Agricultural Research and Extension Services and the weather data measured in near the rice paddy plot. CONCLUSION(S): There was no significant difference between the average rice yields per area in 2000s (2001~2010) and 2010s (2011~2020), but the rice yield variability was greater in 2010s than in 2000s. The mean, minimum, maximum temperature, and the sunshine hours were evaluated for the correlation with the rice yield. The understanding of climate change in Hwaseong-si, Gyeonggi-do and the major weather factors affecting changes in rice yield, presented in this study, would enhance scientific understanding of regional climate change, and improve rice cultivation management.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.209.2-209.2
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• 2005

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2002.11a
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• pp.70.2-70
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• 2002