• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.3
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• pp.18-27
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• 2000

Signal attenuation of Ka-band satellite communication system due to rain fading is more severe than those of conventional frequency band system, thus an efficient rain fade countermeasure technique is absolutely required. In this paper, we design an improved adaptive modulation system, which switches the modulation mode according to the channel condition, and propose the novel synchronization algorithms. We assume that the modulation scheme is M-ary PSK and the receiver is TDMA burst mode. And the transponder model is the same with KOREASAT-3. By using the adaptive modulation scheme, we satisfy the BER and mean spectral efficiency requirements, simultaneously, which is impossible by using the fixed modulation scheme.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.990-996
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• 2005

This paper is countermeasure against the problem point it will be able to occur with infiltration of the hardware and software. And, we proposed the optimum integrated of system construction plan for the SCADA system function set and a system design.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1998.11a
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• pp.92-98
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• 1998

In this paper various drive characteristics of a AC Servo Motor for EV(electric vehicle) and hybrid system proposed a countermeasure against air polution are presented. Since the transfer function of the plant is nonlinear and very complicated, there are difficultly in driving the system with real time. The performance of these experiments is confirmed by computer simulation results. The high performance and high accuracy of the driving system, Field oriented vector control system is proposed.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.804-810
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• 2004

Tilting train can pass curve at higher speed without affecting passenger comfort by tilting Carbody. But the centrifugal force proportional to square of velocity increases the track lateral force. This is the one of the problems to be solved when applying tilting train. The one countermeasure we selected the light weight design by applying distributed traction EMU system and light weight materials such as FRP. The other countermeasure was to adopt steering bogie concept in order to reduce the guiding force on Curve track. This paper describes the design study of self steering mechanism applied to the Bogie for 180 km/h Korean Tilting Train(TTX), which was done as a part of the Korean National R&D project.

• Journal of the Korea Convergence Society
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• v.3 no.1
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• pp.7-11
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• 2012

Intellgent Vehles network capabilities can cause a lots of security issues such as data hacking, privacy violation, location tracking and so on. Some possibilities which raise a breakdown or accident by hacking vehicle operation data are on the increase. In this paper, we propose a security module which has user authentication and encryption functionalities and can be used for vehicle network system.

• Journal of Auto-vehicle Safety Association
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• v.12 no.3
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• pp.20-26
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• 2020

Many children have died (Heat stroke deaths) in the U.S. after being left alone in cars during hot weather, especially summer season. According to related report, more than 800 children have died of heat stroke from being trapped in a hot car since 1998. The regulation party, government has started to make not only technical regulation to prevent tragedy but also legislate to punish. However the 75% of accident has occurred unintended by their parents. So punishment is not the best solution for this case. So in this study, we analyze the trend of regulation and technology to save occupant who remained back seat. And finally we propose a countermeasure to prevent heat stroke deaths.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.10a
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• pp.644-647
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• 2004

Developing into information oriented society, dependency on network systems increases gradually in the area of economy, society and so on. Under that circumstance, temporary stop or damage of integrity of network system may have a strong impact on economic activities and overall society. Recently, threat of cyber terrorism, organized hostile action to government or industry through network, is increasing. Because of the features of network, it is not sufficient only a nation's countermeasure against Cyber terrorism, so international cooperation is needed. We review the status of countermeasure against cyber terrorism and examine several considerations for policy establishment.

• Proceedings of the KIEE Conference
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• 2008.11b
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• pp.98-99
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• 2008

The first swing instability is the very important problem in power system operation. In this paper, the effective countermeasures to the instability. We studied the reinforcement of the transmission lines, generation tripping and reactive compensation are considered as alternative to improve transient stability.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.343-347
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• 2002

This paper analyzed the effect of breakdown electric current and it establishes a countermeasure that objective of the place where it put when with protection method which is applied from the existing electric railroad power supply system and where the protection method which is applied in the newly electrified system. Will reach and in order to attain simulation it did a actual power supply system and it analyzed that result.

• Transactions of the Korean hydrogen and new energy society
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• v.13 no.1
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• pp.65-73
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• 2002

Because of low flame ion density in hydrogen-air mixture, many residual electric energy could be existed in the ignition system of hydrogen engine, If these residual energy discharged abnormally during intake stroke, it may be the cause of backfire occurrence which is serious problem in development of hydrogen fueled engine but unsolved in spite of many concerned research on it. In this study, the possibility of backfire occurrence by abnormal electric discharge and countermeasure of that were investigated by using the experimental single cylinder hydrogen fueled engine with two types of ignition system. The results show that abnormal electric discharge appeared in low load with low ion density and then results in back fire occurrence, It is also seen that countermeasure method installing larger earth resistance in high tension code is effective to control abnormal electric discharge.