• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.1263-1267
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• 2007

A more complete two-dimensional vertical numerical model has been developed to describe the saltwater intrusion in an estuary. The model is based on the previous studies in order to obtain a better accuracy. The non-linear terms of the governing equations are analyzed and the $\sigma$-coordinate system is employed in the vertical direction with full transformation which is recently issued in several studies because numerical errors can be generated during the coordinate transformation of the diffusion term. The advection terms of the governing equations are discretized by an upwind scheme in second-order of accuracy. By employing an explicit scheme for the longitudinal direction and an implicit scheme for the vertical direction, the numerical model is free from the restriction of temporal step size caused by a relatively small grid ratio. In previous researches, some terms induced from the transformation have been intentionally excluded since they are asked the complicate discretization of the numerical model. However, the lack of these terms introduces significant errors during the numerical simulation of scalar transport problems, such as saltwater intrusion and sediment transport in an estuary. The numerical accuracy attributable to the full transformation is verified by comparing results with a previous model in a simply sloped topography. The numerical model is applied to the Han River estuary. Very reasonable agreements for salinity intrusion are observed.

• 디지털산업정보학회논문지
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• 제8권2호
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• pp.59-65
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• 2012

Emergency medical information center performs role of medical direction about disease consult and pre-hospital emergency handling scheme work to people. Emergency medical information system plays a major role to be decreased mortality and disability of emergency patient by providing information of medical institution especially when emergency patient has appeared. But, various attacks as a hacking have been happened in Emergency medical information system recently. In this paper, we proposed security structure which can protect the system securely by detecting attacks from outside effectively. Intrusion detection was performed using rule based detection technique according to protocol for every packet to detect attack and intrusion was reported to control center if intrusion was detected also. Intrusion detection was performed again using decision tree for packet which intrusion detection was not done. We experimented effectiveness using attacks as TCP-SYN, UDP flooding and ICMP flooding for proposed security structure in this paper.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.352-361
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• 2003

We have evaluated the extent of saltwater intrusion from electrical resistivity distribution in a coastal aquifer system in the southeastern part of Busan, Korea. This aquifer system is divided into four layers according to the hydrogeologic characteristics and the horizontal extent of intruded saltwater is determined at each layer through the geostatistical interpretation of electrical resistivity data. In order to define the statistical structure of electrical resistivity data, variogram analysis is carried out to obtain best generalized covariance models. IRF-k (intrinsic random function of order k) kriging is performed with covariance models to produce the plane of spatial mean resistivities. The kriged estimates are evaluated by cross validation to show a good agreement with the true values and the statistics of cross validation represented low errors for the estimates. In the resistivity contour maps more than 5 m below the surface, we can see a dominant direction of saltwater intrusion beginning from the east side. The area of saltwater intrusion increases with depth. The northeast side has low resistivities less than 5 ohm-m due to the presence of saline water in the depth range of 20 m through 70 m. These results show that the application of geostatistical technique to electrical resistivity data is useful for assessing saltwater intrusion in a coastal aquifer system.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2013년도 추계학술대회
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• pp.666-668
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• 2013

모바일 기기의 활성화로 인해 무선 네트워크 환경이 확산되고, 이로 인해 무선 네트워크를 악용하는 사례도 증가했다. 네트워크 보안 및 침입 탐지는 기존 유선뿐만 아니라 무선에도 주목 받고 있으며, 활발하게 연구가 진행되고 있다. Snort 기반의 침입 탐지 시스템(Intrusion Detection System)은 기존 유선 네트워크에서 악의적인 활동 탐지를 위해 널리 사용되고 있는 검증된 오픈 소스 시스템이며, Snort Wireless는 802.11 무선 탐지 기능을 활성화하기 위해 개발되었다. 본 논문에서는 Snort Wireless Rule을 분석하고, 향후 연구 진행방향을 제시한다.

• 소성∙가공
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• 제21권6호
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• pp.384-388
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• 2012

Sheet metal forming processes induce residual stress in the final product due to plastic deformation. The residual stress leads to elastic recovery of the formed part called springback, which causes shape errors in the final product. This error is a serious issue, especially for high strength steels, which are widely used in auto-body structures. Therefore, the evaluation of the amount of springback becomes critical for high strength steels. This paper investigates the springback behavior of DP780 steel sheets after the U-bending process using the geometry of the standard U-shape tool from the NUMISHEET'93 benchmark problem. The amounts of springback were measured as a function of the intrusion direction, forming speed and blank holding force.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.233-236
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• 2008

To analyze the saline intrusion in the place, such as an estuary, the three-dimensional numerical model is developed. In this study, the advection terms of the governing equations are discretized by upwind scheme. By using an explicit scheme for the longitudinal direction and an implicit scheme for the vertical direction, the numerical model is free from the restriction of temporal step size caused by a relatively small grid ratio. The equation of state is used to consider the density, and the scalar transport equation for salinity is employed the third order TVD to scheme to prevent unphysical oscillation near discontinuity. In order to verify saline intrusion, the numerical model is conducted to compare the previous model in the lock exchange. The present model generally show a good agreement with the previous one.

• 대한치과교정학회지
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• 제20권1호
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• pp.169-179
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• 1990

Utilizing the repelling force of permanent magnet of find out weather it shows the findings of molar intrusion histologically and compares the result with the resin bite plane. As for the experimental animals, 10 cats of completion of permanent dentition with mean weight of 2.2kg which have flat occlusal plane of molar areas were used. I raised the cats under the condition of their being attached with manufactured appliance by direct bonding system and of their wearing vertical chin strap anesthetized for 12-14 hours per day through 5 days. Then, observing the root apex areas with lightmicroscope. The results were as follows; 1. In the group with resin bite plane, osteoblasts and osteoclasts could not find out but could find out periodontal ligment fiber obliquely angulated in the apical and lingual direction. 2. In the group with the permanent magnet, not only the obliquely angulated periodontal ligament fiber but also the osteoclasts at the apical areas were observed.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2000년도 추계학술발표논문집 (상)
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• pp.273-276
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• 2000

This paper describes on-going research, applying an artificial immune system to the problem of network intrusion detection. The paper starts by introducing the motivation and rationale of this research. After describing the overall architecture of the proposed artificial immune system fur network intrusion detection, the real network traffic data and its profile features used in this research are explained. As the first step of this effort, the negative selection algorithm, which is one of three significant evolutionary stages comprising an overall artificial immune system, is investigated and initial results are briefly discussed. Finally, the direction of future work is discussed based on this initial result and the contribution of this research is addressed.

• 대한원격탐사학회지
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• 제7권2호
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• pp.95-111
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• 1991

The study is to analyze and interpret lineaments and circular/arc structures on the Landsat TM images which cover the Korean peninsula and the attched islands except the Ulneung island. The Landsat TM images which cover the Korean territory are 23 scenes, and band 3 and band 5 were selected for the study from seven bands, because the both vands are sensitive on soil moisture and geological materials. Lineament trend analysis Sinian direction (NNE-SSW), Pyeongan direction(NW-SE), Yodong direction(NE-SW), Korean direction(NNW-SSE) and Danyang direction (WNW-ESE) are predominant lineament trands of Korea. Circular/arc structures can be devided into four categories according to their origin; 1) volcanic activity origin, 2) granite intrusion oringin, 3) structural origin and 4) the others.

• 항공우주정책ㆍ법학회지
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• 제18권
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• pp.247-324
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• 2003

항공기술의 발달과 더불어 항공기가 날로 무기화하는 추세에 있어서 특히 세계적으로 조밀한 공역을 자랑하는 동아시아에 위치한 우리나라의 입장에 서는 북한과의 대치상황과 더불어 영공 기타 공역에 대한 대응이 현실적으로 절실한 상황이다 그러나, 현재 우리의 관련 법제는 법률적인 차원에서 이에 대한 대응을 하지 못하고, 군 내부의 관련규정에만 의존하고 있어 실제로 침범사고의 발생시에 그 처리에 있어서 많은 문제점이 제기될 가능성이 존재한다. 이 논문에서는 한반도 주변의 공역을 영공, 방공식별구역, 비행정보구역, 배타적 경제수역 상공, 접속수역 상공, 공해 상공으로 구분하여 각 공역의 특성과 이에 대한 우리의 대응조치 등을 살펴보고, 나아가 문제점을 해결하는 방안으로 관련법제의 입법방향에 대해서 검토해 보고자 한다.