• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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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.

• Journal of Korea Society of Digital Industry and Information Management
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• v.8 no.2
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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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• 2003.11a
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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.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.666-668
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• 2013

Wireless network environment is spreading due to the increase of using mobile devices, causing wireless network abuse. Network security and intrusion detection have been paid attention to wireless as well as wired existing and studied actively Snort-based intrusion detection system (Intrusion Detection System) is a proven open source system which is widely used for the detection of malicious activity in the existing wired network. Snort Wireless has been developed in order to enable the 802.11 wireless detection feature. In this paper, Snort Wireless Rule is analyzed. Based on the results of the analysis, present the traveling direction of future research.

• Transactions of Materials Processing
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• v.21 no.6
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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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• 2008.02a
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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.

• The korean journal of orthodontics
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• v.20 no.1
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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.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10a
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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.

• Korean Journal of Remote Sensing
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• v.7 no.2
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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.

• The Korean Journal of Air & Space Law and Policy
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• v.18
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• pp.247-324
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• 2003

Considering Republic of Korea that is known as the worlds one of the most compact airspace, together with development of technology of aerospace and ever-strengthening weapon systems of aircraft, is, in its reality, in a dire need for more practical infrastructure against any intrusion, of course also being mindful of the situation with the North Korea, to its national airspace or other controlled airspace. Republic of Koreas current legislative regime is unable to effectively respond to such crisis on any legal ground, and responsible government members are relying heavily on relevant military laws and regulations. Naturally, there exists strong possibility of various problems when there occurs an actual intrusion to Koreas airspace and lawful and legal resolution of the aftereffect is demanded. This article categorizes Korean peninsula and its national airspace into various kinds of airspaces; KADIZ; FIR; airspace above EEZ; airspace above contiguous zone; airspace above the high sea, and attempted to research and study these respective categories, given the unique nature of airspace and the current responsive measure. Furthermore, this article will review some of the relevant legislative actions and their sense of direction as solution to the discussed problems.