• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.06a
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• pp.80-88
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• 2002

휴대용 컴퓨터의 보급이 확산됨에 따라 이들을 장소에 상관없이 컴퓨터망에 연결시키는 수단으로 무선 LAN의 사용이 확산되고 있으나 무선 LAN 서비스는 전파라는 무선매체를 사용함으로써 정보도용의 가능성이 높으며 감시도 어렵다는 특징을 가지므로 정보보호가 요구된다. 본 논문에서는 IEEE 802.11 표준안 및 IEEE 802.lleS 초안에서 제시하는 무선 LAN의 정보보호기술인 ESN, WEP, AES 및 SMIB에 관하여 기술한다.

• Economic and Environmental Geology
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• v.29 no.3
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• pp.369-380
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• 1996

In order to determine the emplacement time and stratigraphic position of basaltic rocks in the central part of Pohang basin, palaeomagnetic investigations were conducted on 111 samples collected from 6 sites. Formation mean built from site-mean ChRM directions is $d=340.7^{\circ}$, $i=52.2^{\circ}$ (${\alpha}_{95}=6.0^{\circ}$, k=91) in the geographic coordinates. If "tilt" correction is applied regarding the plane perpendicular to the side walls of columnar joint as palaeohorizon, the formation mean becomes $d=328.7^{\circ}$, $i=43.8^{\circ}$ (${\alpha}_{95}=17.1^{\circ}$, k=13). It is to be noticed that the formation mean is deflected significantly (about $20{\sim}30^{\circ}$) counterclockwise from the Tertiary reference geomagnetic field of Eurasia, independent of "tilt" correction. This situation is very different from that of clockwise rotation of ChRM directions which has been ubiquitously observed in other Tertiary basins of south Korea, and indicates sinistral regional simple-shearing during the emplacement times of the basaltic rocks. Considering previous palaeomagnetic and AMS (anisotropy of magnetic susceptibility) data from other Tertiary regions of south Korea, the time of this sinistral shearing should be 15 Ma or directly thereafter, and this time point represents inversion from extensional to compressional tectonic regime. Magnetic foliation data obtained in this study indicate WNW-ESN compression during or directly after emplacement of the basaltic rocks, while it has known from regional tectonic study that the time of the WNW-ESN compression is about 15 Ma, when SW Honshu was rotated and the Korean strait was narrowed.

• The Journal of Information Technology
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• v.12 no.2
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• pp.1-12
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• 2009

China first started its mobile phone services in 1987, and the number of users has exponentially increased so that it reached 700 millions in January 2009. Currently China's 2G(GSM) users is 650 millions. These 2G (GSM) services have an advantage of the capability to use the mobile phone with a SIM (Subscriber Identity Modul) card, one kind of smart cards, inserted into it. However, due to the security vulnerability of SIM cards being used within China's 2G (GSM) services, SIM cards cloning. Problems concerning mobile phone surveillance towards a designated person by illegal cloning ESN and IMSI have recently risen to be a massive social issue within Korea as well. These studies have experimented the possibility of SIM cards clone in various mobile communication corporations using 2G (GSM) in China, and hence discovered the security vulnerability such as the incoming outgoing, SMS service and additional services on mobile phones using clone SIM cards.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2006.06a
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• pp.185-189
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• 2006

최근 ESN과 IMSI 불법복제에 의해 IS-95/cdma2000 이동통신 서비스 정상가입 사용자와 단말의 피해가 확인되고 있다. 이는 정상 가입자의 요금증가, SMS를 통한 휴대폰 결재, 정상단말의 착발신 장애 등의 문제를 일으키고 있다. 이러한 불법복제 단말의 서비스 접근과 정상단말 신원확인을 위해 이동통신 사업자는 파워온 등록, 착신, 발신시에 인증 메커니즘을 적용하지만, 여전히 CDMA/cdma2000 시스템에는 취약점이 존재하는 것으로 분석되고 이의 대응책이 요구된다. 이에 본 논문에서는 파워온 인증, 발신인증, 착신인증이 도입된 이동통신 시스템에서 정상단말과 불법복제 단말이 동일 기지국내에 위치할 때와 서로다른 기지국에 위치할 때, 각각 불법복제 단말에 의해 발생할 수 있는 취약점과 대응방안을 분석하고자 한다.

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.39.2-40
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• 2008

• Proceedings of the Korea Database Society Conference
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• 2010.06a
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• pp.309-318
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• 2010

Nowadays, more and more organizations are implementing the USE' of emerging enterprise 2.0 applications consciously or unconsciously such as Blogs, Wikis, Social Networks, etc. However, as the end users, employee's attitude toward adoption of enterprise 2.0 applications still lacks theoretical support. On the other hand, many organizations which have implemented enterprise2.0 applications are confused about how to promote employees' use of enterprise 2.0 applications. The purpose of this study aims to provide a conceptual examination the determinants that affect employee's adoption of these enterprise2.0 applications using the revised UTAUT model. To test the model, structural equation modeling will be employed to analyze data collected from two organizations in which experimental tests of enterprise social network platforms are conducted. The findings of this research will show effective and reasonable ways of promoting employees' participations in an enterprise 2.0 environment so as to maximize the benefits generated from implementing enterprise 2.0 applications. This research will also provide a theoretical foundation for academics and practical implications for development of enterprise 2.0 applications.

• Journal of the Korea Concrete Institute
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• v.18 no.4 s.94
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• pp.535-542
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• 2006

In Seoul, more than 80 percent of residential buildings are constructed with unreinforced masonry(URM) buildings in early 1970 to 1990. In general, URM buildings have the advantages of reducing the construction time and easy to construction. However, URM buildings do not have enough strength against the lateral force. Moreover, low rise buildings have not adopted seismic designs, and for that reason a critical damage is expected with an earthquake. And also, the necessity of the seismic performance evaluation of existing building structures is raised through the Taiwan earthquake in 1999. The purpose of this study is to provide basic information for unreinforced masonry building in Korea by application of the proposed seismic evaluation method. In this study, seismic capacities of 50 existing unreinforced masonry buildings are evaluated based on the proposed method. Also, relationships of seismic capacities between Korean earthquake damage ratios of korean unreinforced masonry buildings are estimated. Results of this study were as follows; 1)Seismic retrofit was needed $8{\sim}48%$ in Korean unreinforced masonry buildings. 2)Korean unreinforced masonry buildings were expected to have severe damage under the earthquake intensity level experienced in Japan.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.391-393
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• 2022

In recent years, technologies forecasting demand based on deep learning and big data have accelerated the smartification of the field of e-commerce, logistics and distribution areas. In particular, ports, which are the center of global transportation networks and modern intelligent logistics, are rapidly responding to changes in the global economy and port environment caused by the 4th industrial revolution. Port traffic forecasting will have an important impact in various fields such as new port construction, port expansion, and terminal operation. Therefore, the purpose of this study is to compare the time series analysis and deep learning analysis, which are often used for port traffic prediction, and to derive a prediction model suitable for the future container prediction of Busan Port. In addition, external variables related to trade volume changes were selected as correlations and applied to the multivariate deep learning prediction model. As a result, it was found that the LSTM error was low in the single-variable prediction model using only Busan Port container freight volume, and the LSTM error was also low in the multivariate prediction model using external variables.