• 한국연소학회:학술대회논문집
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• 2000.05a
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• pp.142-151
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• 2000

Dump combustor is a combustor having a dump plane to make coherent structures. A non-premixed flame dump combustor of simple geometry was constructed. We conducted basic experiments such as frequency response on the combustor to confirm the characteristics of the phenomena as a typical dump combustion and unsteady combustion. Furthermore we visualized the flame front behavior by CH chemiluminescence and high speed motion analysis. In spite of the lack of another data such as velocity, species concentration and temperature, the results showed not only the periodic motion of flame front but the ignition process of vortex ring flame. Also we could check out Rayleigh criterion by combining the visualization data with the pressure data.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.259-262
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• 2000

Chua's circuit is a simple electronic network which exhibits a variety of bihucation and attractors. The circuit consists of two capacitors, an inductor, a linear resistor, and a nonlinear resistor. In this paper, a transmitter and a receiver using two identical Chua's circuits are proposed anti synchronizations of a equivalent power line are investigated. Since the synchronization of the equivalent power line system is impossible by coupled synchronization, theory having both the drive-response and the coupled synchronization is proposed. Af a result, the chaos synchronization has delay characteristics in the equivalent power line transmission system caused by the line parameters L and C.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.610-613
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• 2000

Recently catastrophic oil spills from tanker casualties have polluted the marine environment. In this paper, the Sea Prince casualties are analyzed and the systems to be introduced are considered. Also, the establishment of the national contingency plan and the decision-making procedure based on technical analysis are described. Based on the discussions the Rapid Response Technical Support System is derived for the support of salvage and oil spill removal operation, The System will contribute to the protection of life and assets from the marine casualties and to keeping the clean and safe ocean.

• Korean Journal of Oriental Medicine
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• v.6 no.1
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• pp.81-87
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• 2000

Chungpesagan-Tang (CST), a Korean traditional prescription composed of oriental medical herbs, has been used successfully to improve human health and regimen. This study was designed to examine the inhibitory effects of CST against in vitro ischemia/reperfusion-induced inflammatory response. We have characterized the production of prostaglandin $E_2$ and arachidonic acid during ischemia/reperfusion in the human neuroblastoma SK-N-MC and human monocytic macrophage U937 cells and the inhibitory effect of CST on these inflammation-related substance formation has been found out in this study. This result suggested that CST used in this experiment reinforced antiinflammatory potentials and protected cells against ischemia/reperfusion-induced inflammatory resopnse.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.516-518
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• 2000

This paper presents a methodology for effective control of fuel cell devices connected to the electric utility distribution network. A controller is designed for a fuel cell power plant to assist the conventional generators to damp out oscillations, which is possible by utilizing the fast response characteristic of fuel cells. Computer model of the controller is proposed and its effectiveness is proved by a sample test. Fuel cell devices can be used to improve power system stability when these are connected to a distribution system.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.379-381
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• 2000

In the new electric industry, many of generators and consumers exist in competitive market and electric price is determined by the response of suppliers and consumers. Power supply and consumption make change the electric price and social welfare depends on the elasticity that indicates sensitivity to changes of price related on the electric demand or supply. If elasticity is changed, social welfare that represents the sum of producers and customers surplus will be changed together. This paper investigates the change of the social welfare depending on the elasticity, and presents the propriety of competitive electric market.

• The Korean Journal of Applied Statistics
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• v.13 no.2
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• pp.477-488
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• 2000

A distance measure between two Latin-hypercube designs is defined and its expected value is computed. It was computed by using mathematical statistics, numerical analysis (multidimensional numerical integration), Monte-carlo method, and the theory of asymptotic normal distribution. For the comparison of two Latin-hypercube designs with same structure but different randomness, the difference of expected values of response function and information mass of experimental designs are considered. These methods may be useful in comparison between two general experimental designs.

• Korean Security Journal
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• no.5
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• pp.211-241
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• 2002

Koreans are the most avid Internet surfers in the world according to Nielson/NetRatings(Reuters, August 2001) and most Internet connections are made through high-speed connections like Digital Subscriber Lines (DSLs). The result of such internet fervor is a nation that is fertile in both hackers and software companies(over 200 in the field of network security alone). However, by-product of Internet activity is cyber crime and the need to protect innocent users from the dangers of cyber criminals and cyber-terrorists be they are individuals or organized groups. Hence the Cyber Terror Response Team (CTRT) was organized in late 2000 with the mandate to fulfill that role. In these contexts, this study analyzes the actual conditions of cyber terror and suggests the countermeasures against cyber terror in Korea.

• Proceedings of the KWS Conference
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• 2000.10a
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• pp.260-263
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• 2000

A methodology is developed and many used to evaluate the response sensitivity of the thermal systems to variations in their design parameters. Technique for computing the sensitivity of temperature distributions to changes in processing parameters needed for deciding the more effective laser input parameters for laser surface hardening treatment are considered. In this study, a state equation governing the heat flow in laser surface treatment is analyzed using a three-dimensional finite element method and sensitivity data of the processing parameter obtained using a direct differentiation method applied for sensitivity analysis. The interesting processing parameter is taken as the laser scan velocity and characteristic beam radius( $r_{b}$) of the sensitivity of the temperature T versus v and $r_{b}$ is analyzed. And these sensitivity results obtained in another parameters are fixed condition. To verifying the numerical analysis results, hardened layer dimensions (width and depth) of the numerical analysis compared with the results of an experimental data.ata.

• Transactions on Control, Automation and Systems Engineering
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• v.2 no.3
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• pp.175-181
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• 2000

This paper investigates the robust nonlinear H$_{\infty}$ filter with FIR(Finite Impulse Response) structure for nonlinear discrete time-varying uncertain systems represented by the state-space model having parameter uncertainty. Firstly, when there is no parameter uncertainty in the system, the discrete-time nominal nonlinear H$_{\infty}$ FIR filter is derived by using the equivalence relationship between the FIR filter and the recursive filter, which corresponds to the standard nonlinear H$_{\infty}$ filter. Secondly, when the system has the parameter uncertainty, the robust nonlinear H$_{\infty}$ FIR filter is proposed for the discrete-time nonlinear uncertain systems.