• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1995.10a
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• pp.667-672
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• 1995

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1986.10a
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• pp.119-124
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• 1986

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.43 no.4 s.310
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• pp.80-87
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• 2006

Recently, the distribution and using of the digital multimedia contents are easy by developing the internet application program and related technology. However, the digital signal is easily duplicated and the duplicates have the same quality compare with original digital signal. To solve this problem, there is the multimedia fingerprint which is studied for the protection of copyright. Fingerprinting scheme is a techniques which supports copyright protection to track redistributors of electronic inform on using cryptographic techniques. Only regular user can know the inserted fingerprint data in fingerprinting schemes differ from a symmetric/asymmetric scheme and the scheme guarantee an anonymous before recontributed data. In this paper, we present a new scheme which is the detection of colluded multimedia fingerprint by neural network. This proposed scheme is consists of the anti-collusion code generation and the neural network for the error correction. Anti-collusion code based on BIBD(Balanced Incomplete Block Design) was made 100% collusion code detection rate about the average linear collusion attack, and the hopfield neural network using (n,k)code designing for the error bits correction confirmed that can correct error within 2bits.

• Convergence Security Journal
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• v.7 no.1
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• pp.29-34
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• 2007

Recently, the distribution and using of the digital multimedia contents are easy by developing the internet application program and related technology. However, the digital signal is easily duplicated and the duplicates have the same quality compare with original digital signal. To solve this problem, there is the multimedia fingerprint which is studied for the protection of copyright. Fingerprinting scheme is a technique which supports copyright protection to track redistributers of electronic information using cryptographic techniques. Only regular user can know the inserted fingerprint data in fingerprinting schemes differ from a symmetric/asymmetric scheme and the scheme guarantee an anonymous before re-contributed data. In this paper, we present a new scheme which is the detection of colluded multimedia fingerprint by neural network. This proposed scheme is consists of the anti-collusion code generation and the neural network for the error correction.

• Journal of the Korean Society of Radiology
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• v.9 no.6
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• pp.403-408
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• 2015

Hard X-ray has been widely used in medical and industrial fields because it can be applied to observe the inside of a sample. Computed tomography provides sectional images of the sample through the reconstruction of the projection images. The quality of sectional images strongly depends on that of projection images. Ring artifact appeared on the seconal image can be made by the abnormal pixels of the detector used. In this study, we examine the ring artifact ratio in the circle phantom as a function of detection error of the detector used in computed tomography. The ring artifact increased with the increment of detection error under parallel and fan beam geometries and strongly increased near the center of rotation. The corrections, dead pixel and flat field corrections, for the images taken with the detector are required before the image reconstruction process to reduce the ring artifact in the computed tomography.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.10a
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• pp.498-501
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• 2004

본 논문에서는 엘리베이터의 제어 신호들과 액추에이터들을 동작시키기 위한 릴레이 그리고 액츄에이터의 동작을 센서와 포토 커플러를 이용하여 샘플링 한다. 제안하는 시스템에서는 예외적인 상황에서 오류가 발생하는 사례를 퍼지 데이터베이스로 구성하고 산출된 엘리베이터에러를 최종적으로 엘리베이터 관리자에게 통보함으로써 사고 발생 시 즉각적인 대책과 인명피해에 대한 빠른 구조 활동을 계획할 수 있도록 한다. 시스템에 사용된 알고리즘은 제어 신호를 입력으로 한 퍼지 if-then rule 이며, 관리자와의 통신은 Bluetooth를 통하여 Embedded Server에 신호를 전송하고 최종적으로 Embedded Server에서 인터넷 IP를 통하여 관리자에게 에러 발생 여부를 통보하게 된다. 인터넷 IP를 활용함으로써 거리의 제약이 사라지고 실시간으로 엘리베이터의 상태를 파악 할 수 있게 된다. 궁극적으로 승객의 안전과 편의를 도모하기 위해 본 논문의 시스템이 제안되었다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2017.11a
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• pp.21-23
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• 2017

본 논문에서는 스펙트럼 감지 무선 인지 네트워크에서 동기화 에러가 존재하는 환경을 고려한다. 동기화에러가 존재 할 때 주어지는 오검출 확률(miss detection probability)을 이용하여 일차 사용자와 이차 사용자들 간의 충돌 확률(collision probabliyt)를 유도한다. 유도된 수식을 몬테 카를로 모의실험(Monte Carlo simulation)을 통해 확인한다.

• Proceedings of the KAIS Fall Conference
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• 2001.05a
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• pp.195-198
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• 2001

본 논문에서는 최근 그 응용이 증가하고 있는 CAN통신 프로토콜을 이용하여 차량내 network개념을 도입하여 차내 각종 전기신호와 센서 입출력을 제어하는 통합 시스템의 개발에 관한 것을 간략히 기술한다. CAN시스템은 최대 1Mbps의 전송 비트율과 에러검출 및 에러영향의 시스템 내로의 한정 등의 기능이 뛰어난 높은 레벨의 통신 안정성을 가지면서 분산 실시간 제어를 효율적으로 지원하는 serial bus communication프로토콜의 하나이다. 본 연구에서 개발된 시스템은 4개의 독립 제어시스템과 관련 소프트웨어로 구성되어 있으며. 각각의 제어시스템간의 정보의 교환은 CAN통신 프로토콜에 안정적으로 이루어지며 자동차의 고급화와 함께 향후 실용화가 기대된다.

• Journal of Broadcast Engineering
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• v.25 no.6
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• pp.870-881
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• 2020

This paper presents cell ID (cell identity) detection schemes using PSS/SSS (primary synchronization signal/secondary synchronization signal) for 5G NR (new radio) system and evaluates the detection performance. In this paper, we consider two cell ID detection schemes, i.e. two-stage detection and joint detection schemes. The two-stage detection scheme consists of two stages which estimate a channel gain between a transmitter and receiver and detect the PSS and SSS sequences. The joint detection scheme jointly detects the PSS and SSS sequences. In addition, this paper presents coherent and non-coherent combining schemes. The coherent scheme calculates the correlation value for the total length of the given PSS and SSS sequences, and the non-coherent combining scheme calculates the correlation within each group by dividing the total length of the sequence into several groups and then combines them non-coherently. For the detection schemes considered in this paper, the detection error rates of PSS, SSS and overall cell ID are evaluated and compared through computer simulations. The simulation results show that the joint detection scheme outperforms the two-stage detection scheme for both coherent and non-coherent combining schemes, but the two-stage detection scheme can greatly reduce the computational complexity compared to the joint detection scheme. In addition, the non-coherent combining detection scheme shows better performance under the additive white Gaussian noise (AWGN), fixed, and mobile environments.

• Journal of Digital Contents Society
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• v.7 no.3
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• pp.169-174
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• 2006

In recent years, RFID is widely used in industrial applications including factory, material flow, logistics and defense areas. In this paper, The convolutional encoding and viterbi decoding is also implemented to improve the system performance. in an FPGA chip. The used convolution code is constraint length K=3 and rate R=1/2. The length of command frame and response frame is total of 48bits consisting of SOF 8 bits, command 16 bits, CRC 16 bit, and EOF 8 bits. And also the frame error rates are measured under the channel of line-of-sight and non line-of-sight, respectively. The performances are analyzed with FSK modulation only and FSK modulation added with convolutional encoding. These two measured results are compared with that of a RFID system with ASK modulation.