• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.558-561
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• 2002

In the embodiment of power line modem, the important elements are selection of a suitable line-coupler, choice of a modulation method good for channel environments, and an efficient data coding method etc. In this paper an appropriate modulation method was implemented their results in details and verified by the simulations. The data compensation request techniques that uses error checking was discussed. Finally, application of other modulation method by detection of error rate per bit according to vary of channel error caused by electric equipment that is connected to power line was studied.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2002.11a
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• pp.3-8
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• 2002

A new Modem technique - 8-state Superposed QAM(8SQAM) - for use in power and bandwidth limited digital communication system is proposed. The premodulation baseband signal of the 8SQAM system is a double-interval(2Ts) raised cosine pulse superposed with weighted single-interval(Ts) raised cosine pulse. The performance of the 8SQAM, in a nonlinearly amplified multi-channel environment with additive white Gaussian noise(AWGN), inter-symbol interference(ISI), inter-modulation(IM) and adjacent channel interference(ACI), is analyzed via computer simulation. The simulation result shows that the 8SQAM outperforms 8PSK by about 1.6㏈ at BER=$1\times10^{-4}$ when HPA IBO is 1㏈ and channel Spacing, ${\Delta}F$ is 0.417fb.

• Journal for History of Mathematics
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• v.17 no.4
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• pp.77-86
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• 2004

Felix Klein profoundly influenced mathematical developments throughout the world by showing a new direction for modem geometry. He also influenced the lives of excellent scientists like Einstein by reforming mathematical education. The first Felix Klein medal of the Internal Commission on Mathematical Instruction was awarded at ICME-10 in July of 2004. In this article, we discuss Klein's Erlangen Program and investigate his influence on modem mathematics and mathematical education with this medal as momentum.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.14 no.1
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• pp.11-21
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• 1989

In this paper, a GMSK modulator was implemented with a gaussian lowpass filter using digital signal processing, a phase integration, D/A convers and auxiliary circuits. The relatively narrow bandwidth of power spectrum of the GMSK modulator is observed when the cut off frequency (B T) of the gaussian baseband filter is varied. In a demodulator, a discriminator type circuit is used. Using the above degital radio GMSK modem, BER is theoretically derived and experimentally measured when 16Kbps PRBS data is transmitted under Rayleigh fading and additive white gaussian noise conditions.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2637-2639
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• 2002

This paper presents the design and implementation of a baseband Modem using DSP that supports a wireless LAN. It is implemented with DSP and D/A and A/D Converters in baseband and tested without using IF and RF modules. In this paper, we have used the matched filler and DLL(delay lock loop) for synchronization. And the matched filter and the carrier recovery are directly connected. Therefore, the proposed architecture is very simple and the operation of DSP becomes fast.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.05
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• pp.167-170
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• 1995

A quadrature-channel MODEM using amplitude modulation was constructed. To test the MODEM, 6.4 MHz sinusoidal wave 1 KHz triangular wave were modulated, then the modulated signal was fed into the demodulator, to reconstruct the triangular wave.

• Journal of the Korea Safety Management & Science
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• v.2 no.1
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• pp.99-116
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• 2000

Accident statistics cite the flightcrew as a primary contributor in about 70 percent of accidents involving transport category airplanes. The introduction of modem flight deck designs, which have automated many piloting tasks, has reduced or eliminated some types of flightcrew errors, but other types of errors have been introduced. To identify the impedimental factors in highly automated modem airplane cockpit systems, this study used readily available information sources and case study, From the evidence, this study identified issues that show vulnerabilities in pilot management of automation, situation awareness, communication between pilots and controllers, pilot's training and evaluation methods. The next step will require the aviation community to solve these problems for the safety improvement.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.917-920
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• 2006

It is possible to make a practical application for many services by using Home Networking. It's brings much improve the quality of our life. Remote control communication should be made by Home Network but present networks are generally using wireless Internet. But, this method don't use exist home and not install wireless internet. Because It need to many devices. Therefore, in this paper we implement gas valve remote control system using RPM(Radio Packet Modem). We can easily installing systems and operating. This system provide different solution for Home networking.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.415-418
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• 2001

Korean government regulates the technical specifications for the terminal equipments connecting to public telephone network, while equipments in the market are subjected to the type-approval confirming with the technical specifications. foreseeing the revision of the technical specifications, this paper discussed on technologies considered to be additional to the specifications including ADSL modem and power-line communication equipment.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2001.05a
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• pp.69-72
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• 2001

We are defined a space as the activities of creating value in harmonic relations between human and environment. After Industrial Revolution, relations between human and space is changing because of speed and visualization's power in contemporary society. We we known information where is far by means of visualization. There is only difference of speed. Movement in space means the line of vision and circulation. But it is tried to think relations between human and space again in result to experience indirectly. This study aims at the analysis of expression of the modem Architecture space in Giedion' Space, Time, Architecture and aesthetic systems applied to it. On the basis of that , this study analyzed the difference of Bergson' consideration from Modern Architecture about movement.