• 전기저널
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• 7호통권127호
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• pp.32-35
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• 1987

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국내학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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• pp.683-687
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• 1988

Digitalization of processor and increase of control information need the fiber optic data network which has excellent noise immunity and high-quality, widebaudwidth information transfer capability. It is aimed to offer a fiber optic dataway system for measuring and control the power plant, that has high reliability, high data transmission rate and small cable duct with large transmission capacity.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제48권1호
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• pp.42-47
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• 1999

This paper presents the information transmission between on-board and ground-site in MAGLEV. considering safety and high speed operation and density operation, information transmission between them is necessary. Therefore it is necessary for transmission system to ensure high speed transmission, low error rate, massive information, and reliability of information. To provide above conditions, 1.1km signal line assembly was constructed and Frequency Shift Keying(FSK) modulation and Open System Interconnection(OSI) based high-level data link control(HDLC) protocol are applied. To modulate digital signal for transmission from ground-site to on-board, carrier frequency of 70kHz is used and 90khz is used for transmission from on-board to ground-site. Transmission speed is 2400bps for consideration of train speed, quantity of information, and data error rate. And this paper introduces information monitoring considering user interface and presents the method for an effective data transmission in MAGLEV which is now being tested and intends to provide for an intelligent train operation system in future.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 A
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• pp.465-467
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• 1999

The data transmission system in MAGLEV is required a high quality and high speed for a train safety and reliability driving. In the transmission channel between a vehicle and a ground-site, Gaussian noise is negligible, but impulse noise from the chopper controlled propulsoin unit and the Power supplying device is very severe. The transmission channel must be protected from these noise. In this paper, we propose a DSSS (direct-sequence spread spectrum) modulation as a new data transmission technique in the railway and analyze this data transmission characteristics.

• 전자공학회논문지CI
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• 제45권6호
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• pp.68-76
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• 2008

모바일 애드 혹 네트워크(MANET)는 네트워크 토폴로지의 변화로 인해 데이터 전송의 정지확률과 경로가 끊어질 확률이 높아 경로 유지가 힘들다. 이러한 MANET의 특성 때문에 안정적인 데이터 전송률을 보장하기 어렵다. 따라서 노드 간 링크의 데이터 전송률에 대한 신뢰도를 평가하고, 이에 기반을 둔 라우팅 알고리즘이 필요하다. 이에 본 논문에서는 링크 신뢰도 기반 라우팅을 다음과 같이 제안한다. 먼저 과거 정보를 사용하여 가설을 추론하는 베이지안 추론을 적용하여 노드 간 링크의 신뢰도를 측정 할 수 있는 링크 신뢰도 측정 모델을 제안한다. 또한, 노드의 흡수와 노드 간의 연결성을 고려한 기존의 OLSR 프로토콜에 추가적으로 링크 신뢰도 측정 모델을 적용한 링크 신뢰도 기반 OLSR 프로토콜을 제안한다. NS-2를 사용한 시뮬레이션 결과는 링크 신뢰도 측정 모델을 적용한 OLSR 프로토콜이 기존의 OLSR 프로토콜에 비해 전송 성공률과 안정성 측면에서 성능이 우수함을 보여준다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.448-453
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• 2005

For under-water communication system, due to limit of bandwidth and reflect of under-water wave, it is difficult to implement high-reliability high-speed digital communication system. To apply high-reliability and high-speed communication system for under-water system, the efficient combine the channel design with the use of multiple transmit and/or receive antennas. Therefore this paper analyze the space time coded system for under-water communication environment.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1105-1108
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• 2004

As recently optical communication industry is developed, request of optical communication part is increased. Ferrule is very important part which determines transmission efficiency and quality of information in the optical communication part. Most of ferrule processes are grinding which request high processing precision. The ultra precision centerless grinding machine for ferrule grinding was designed. The centerless grinding machine is composed of the high damping bed, grinding wheel spindle unit, regulating wheel spindle unit, feeding table and dressing unit. Reliability prediction was very important for the high quality design. In this study, centerless grinding machine was predicted reliability.

• ETRI Journal
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• 제25권1호
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• pp.1-8
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• 2003

This paper introduces an efficient iterative decoding method for high-dimensional block turbo codes. To improve the decoding performance, we modified the soft decision Viterbi decoding algorithm, which is a trellis-based method. The iteration number can be significantly reduced in the soft output decoding process by applying multiple usage of extrinsic reliability information from all available axes and appropriately normalizing them. Our simulation results reveal that the proposed decoding process needs only about 30% of the iterations required to obtain the same performance with the conventional method at a bit error rate range of $10^{-5}\;to\;10^{-6}$.

• Applied Microscopy
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• 제45권2호
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• pp.89-94
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• 2015

This article briefly reviews the results of recently reported research on high-temperature Pb-free solder alloys and the research trend for characterization of the interfacial reaction layer. To improve the product reliability of high-temperature Pb-free solder alloys, thorough research is necessary not only to enhance the alloy properties but also to characterize and understand the interfacial reaction occurring during and after the bonding process. Transmission electron microscopy analysis is expected to play an important role in the development of high-temperature solders by providing accurate and reliable data with a high spatial resolution and facilitating understanding of the interfacial reaction at the solder joint.

• 한국정보기술응용학회:학술대회논문집
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• 한국정보기술응용학회 2005년도 6th 2005 International Conference on Computers, Communications and System
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• pp.77-80
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• 2005

Wireless sensor networks(WSN) technology has various applications such as surveillance and information gathering in the uncontrollable area of human. One of major issues in WSN is the research for reducing the energy consumption and reliability of data. A system with forward error correction(FEC) can provide an objective reliability while using less transmission power than a system without FEC. In this paper, we propose to use LDPC codes of various code rate(0.53, 0.81, 0.91) for FEC for WSN. Also, we considered node-to-node interference in addition to AWGN channel. The proposed system has not only high reliable data transmission at low SNR, but also reduced transmission power usage.