• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.536-539
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• 2002

The use of concatenated codes in noncoherent synchronous optical fiber CDMA networks is proposed. The concatenated code sequences are generated using balanced Walsh code sequences and Walsh code sequences. The selection of balanced Walsh code sequences is presented and the design of fully programmable transmitter and receiver is reported. The analysis of the system BER performance shows that multiple-access interference is completely eliminated and the BER performance of the proposed system is better than that of the non-coherent synchronous optical fiber CDMA system using optical orthogonal codes with double hard-limiters.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.425-428
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• 1999

Turbo decoder were shown to achieve performance within 0.7㏈ of the Shannon capacity limit. This constituted a significant gain in power efficiency over other coding techniques known at the time. In this paper, Turbo code with constraint length K＝4, code rate 1/3, frame size 196bits(6 tail bits), 20㎳ frame and 6bit MAP decoder is implemented using VHDL. The designed Turbo code is used for voice service. Interactions of the system are used to attain large performance improvements.

• Journal of the Chungcheong Mathematical Society
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• v.22 no.3
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• pp.367-374
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• 2009

The errors take place in the communication channel but they are often burst-error types. From properties of the Fi-bonacci code, it is not difficult to detect the burst-errors accompanying with this code. Fibonacci codes for correcting the double-burst-error patterns are presented. Given the channel length with the double-burst-error type, Fibonacci code correcting these errors is constructed by a simple formula.

• Proceedings of The KACE
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• 2018.08a
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• pp.155-158
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• 2018

수출입 기업이 관세 혜택을 받거나 올바른 관세를 측정하기 위해서는 통관 진행 시 올바른 품목 분류가 선행되어야 한다. 그러나 품목 분류의 기준이 1만개가 넘을 정도로 방대하여 신규 사용자나 품목에 이해가 부족할 경우 분류에 어려움이 따른다. 이러한 HS Code 분류의 한계점을 보완하기 위해 빅데이터 기반 이미지 분석을 통한 자동 제안 시스템을 목표로 하였다. 본 논문에서는 이미지 분석을 통한 HS Code 자동 제안시스템을 위한 수출입 품목 중 의류 품목의 수출입 품목에 국한하여 의류 HS Code 자동 분류 시스템을 설계하고, 제안한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.10a
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• pp.130-132
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• 2015

The IMO Polar Code was adopted by Res.MSC.385(94) and Res.MEPC.264(68) and will enter into force on 1 January 2017. The Polar Code will affect design and equipment of ships intending to operate in polar areas. In this study, the requirements in the Polar Code are analysed from the perspective of class.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.465-467
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• 1989

Many Korean graphic cards have been produced. But, due to the diversity of korean code system all korean graphic cards produced have been adapted in specific code system. Therfore, considering in KSC-5601-1987, the paper propose a Korean decoder independent of code system

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1964-1965
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• 2002

This paper reports on the single mode fiber coupling efficiency. There is difference between simulation by CODE-V and theoretical result, we observed CEO which is taken by experiment in lab and found out that CEO taken by CODE-V was closer to real experiment result then theoretical result.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1995.06a
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• pp.59-61
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• 1995

An adaptive code rate change scheme in DS-SSMA systems is proposed. In the proposed scheme, the error correcting code rate is changed according to the channel state, the effective number of users. The channel state is estimated based on retransmission requests. The criterion for the change of the code rate is to maximize the throughput under given error bound.

• Journal of Biomedical Engineering Research
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• v.5 no.1
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• pp.93-102
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• 1984

In this paper, the real-time compressed code generation method for the biological signal data, especially for the Electrocardiogram, is studied. For this purpose, variable length code is introduced. And from this code, we get a exactly the same reconstructed signal data as the original. Experimental results show that this program reduces the data rate by a factor of about 8, and codes the result in a form convenient for analysis.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.2
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• pp.152-161
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• 2009

As follow jamming signals in a FHSS system cause malfuctioning in the code tracking circuits using early-late gates, we need a code tracking circuit that is robust against the follow jamming signals. In this paper, we propose a code tracking circuit using a linear clipper-Gaussian filter algorithm to remedy the malfunctioning due to the follow jamming signals in FHSS systems. We investigate the mechanism of the malfunctioning of the code tracking circuit and verify that the proposed linear clipper-Gaussian filter metigates the problem through mathematical analysis and computer simulations.