• Journal of the Korea Society of Computer and Information
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• v.8 no.3
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• pp.34-39
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• 2003

There have been several researches to trace intruders on the Internet. But, up to now, few of them has shown a satisfactory and practicable result of the study. Recently, a little bit more active methods such as 'counter-attacking' have been considered to be an alternative to solve the problem of hacking, and some people showed a tendency to accept the method as one possible way to protect their systems. And the new intruder-retracing method suggested in this study is an improved AIAA(Autonomous Intrusion Analysis Agent) model which has been achieved by attaching the counter-attacking method to the existing tracing system. In this paper, the automatic intruder-tracking system is proposed, which was achieved through the design of the following three modules, such as the intruder-retracing module, intruder-tracing module and AIAA dispatch module.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.1 no.2
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• pp.33-38
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• 2008

The baseline wander of ECG makes difficult to detect P-, Q-, R- and S-wave. This paper presents and compares two method to remove the baseline wander of ECG using slope traceing waves. For the first method that had been proposed already[1], the ascending slope tracing method is used to eliminate baseline wander. And the second method employs the contour of the approximated S-wave to remove baseline wander. These two methods are common to use the slope tracing wave. However, the first one is to get difference signals between the ascending tracing waves and ECG signals, and the other is to remove baseline wander using the contour of the approximated S-wave obtained from descending slope waves. To evaluate these methods, we apply to MIT/BIH database.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.304-309
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• 1997

A method to mitigate the thermal stratification flow of a horizontal pipe line is proposed by heating external bottom of the pipe with electrical heat tracing. Unsteady two dimensional model has been used to numerically investigate an effect of the external Denting to the thermally stratified flow. The dimensionless governing equations are solved by using the control volume formulation and SIMPLE algorithm. Temperature distribution, streamline profile and Nusselt numbers of fluids and pipe walls with time are analyzed in case of externally heating condition. no numerical result of this study shows that the maximum dimensionless temperature difference between the hot and the cold sections of pipe inner wall is 0.424 at dimensionless time 1,500 ann the thermal stratification phenomena is disappeared at about dimensionless time 9,000. This result means that external heat tracing can mitigate the thermal stratification phenomena by lessening $\Delta$ $T_{ma}$ about 0.1 and shortening the dimensionless time about 132 in comparison with no external heat tracing.rnal heat tracing.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.06a
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• pp.799-802
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• 2007

Broadcast encryption has been applied to transmit digital information such as multimedia, software and paid TV programs on the open networks. This paper presents a method called Traitor Tracing to solve all these problems. Traitor tracing can check attackers and trace them. It also utilizes a proactive way for each user to have effective renewal cycle to generate keys.

• Transactions of Materials Processing
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• v.4 no.3
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• pp.267-281
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• 1995

Preform design is one of the critical fields in metal forming. The finite element method(FEM) has been effective in designing preforms and process sequence, for which the backward tracing scheme of the rigid-plastic FEM has been explored. In this work a program using the backward tracing scheme by the rigid-plastic FEM is developed for three-dimensional plastic deformation, which is an extension of the scheme from two-dimensional cases. The calculation of friction between workpiece and die, and handling of boundary conditions during backward tracing require sophisticated treatment. The developed program is applied to upsetting of a rectangular block and to side pressing of a cylindrical workpiece. The results of the two applications show feasibility of the program on three-dimensional plastic deformation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.7
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• pp.2118-2133
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• 1996

A preform is designed by the backward tracing scheme of the rigid-plastic finite element method(FEM) for net-shape shell nosing components without machining after forming. The current process of the shell nosing requires cost-consuming machining to produce final products. Here, the backward tracing scheme of the rigid-plastic FEM, a novel method for preform design of metal forming processes, derives a sound preform for net-shape shell nosing product. The current process is simulated by the rigid-plastic finite element analysis to check the metal flow involved in the forming with a trial preform and its modified preform. The two preforms are found to be inadequate for net-shape shell nosing product. The first application of the back ward tracing scheme derives a preform producing a not-shape shell nosing product. The first application of the backward tracing scheme derives a preform producing a net-shape product numerically, but it is difficult to be formed economically as a preform. Thus an improved preform is designed by the badkward tracing scheme, which is suitable for net-shape manufacturing of the shell nosing components in view of economy of production and forming characteristics of the product. The preform in the current process and a modified preform are confirmed by a series of experiments and the results give the same deformation with the numerical ones. Finally the newly designed preform by the FEM was experimentally proved to be adequate in obtaining net-shape products.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.52-55
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• 2002

In this research, the modification method of spherical aberration, and aspherical lens shape design method were investigated. Spherical aberration affects lens's performance directly. Many studies have attempted to remove spherical aberration with a lot of methods in order to reduce the bad effect of spherical aberration. The approach to lens shape design was base on the ray tracing method. From the result, it was confirmed that ray reverse-tracing method was convenient to remove spherical aberration, and could be used very effectively and usefully for aberration-free aspherical lens design.

• Transactions of Materials Processing
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• v.26 no.5
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• pp.300-305
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• 2017

In this paper, a design method for an intermediate die was developed to manufacture a hollow linear motion guide rail in mandrel drawing process based on virtual die method and backward tracing scheme. FE simulations and mandrel drawing experiments using Mn55Cr carbon steel were performed to prove the effectiveness of the proposed design method. Results of FE simulations and experiments showed that the proposed design method could lead to drawn products with sound shape and the highest dimensional precision.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.727-732
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• 2014

The goal is to find the position of the sound source with the TRM at reflections and refractions environment. The Fermat's principle applied to the ray tracing method are expected to follow the acoustic path in order to obtain acoustic distance and transmittance to. Utilizing them in the TRM was confirmed rear reflectance affect on estimated position, resolution and side lobe. And the TRM performance were superior to one of the beam forming techniques.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.4
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• pp.366-376
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• 2015

The Gothic arch tracing method using a Gothic arch tracer which is one of the centric relation recording methods can reproduce mandibular movement more accurately by describing the path of mandibular curvilinear motion. This case reports that we have satisfactory results by recording reproducible centric relation using a gothic arch tracing method in a patient who has difficulty to induce centric relation by operator due to parafunctional movement.