• Ocean Systems Engineering
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• 제8권1호
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• pp.33-39
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• 2018

The paper presents a numerical underwater channel model developed in MATLAB for estimating the optical link budget between a light emitting diode (LED) based optical transmitter and a photo diode (PD) receiver when operated in the harbor, coastal and deep waters locations in the Bay of Bengal. The water samples are collected at different locations in the Bay of Bengal using a water sampler during an offshore research cruise. The optical attenuation, the main inherent parameter determining the range of the optical communication link is identified for the different waters using an underwater irradiance measurement system in the laboratory. The identified parameters are applied to the numerical model and found that a 10 W LED and a photo diode based system can provide the optical budget required for a horizontal underwater communication range of about 0.5, 14 and 35 m in the harbor, coastal and deep waters locations respectively. By increasing the transmitter power to 50 W, the operating range of the communication link could be increased up to 53 m in deep water locations in the Bay of Bengal.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.1245-1247
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• 2004

This paper considers the design and implementation of novel technique of speed estimation and control for IPMSM using hybrid intelligent control. The hybrid combination of neural network and adaptive fuzzy control will produce a powerful representation flexibility and numerical processing capability. Also, this paper is proposed speed control of IPMSM using adaptive neural network fuzzy(A-NNF) and estimation of speed using artificial neural network(ANN) controller. This paper is proposed the theoretical analysis as well as the simulation results to verify the effectiveness of the new hybrid intelligent control.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권10호
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• pp.2527-2543
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• 2013

A novel steganographic QR code algorithm, which not only coveys the secret into the widely-used QR barcode but also preserves the readability of QR content and the capability of error correction, is presented in this article. Different from the conventional applications for QR barcode, the designed algorithm conceals the secret into the QR modules directly by exploiting the error correction capability. General browsers can read the QR content from the QR code via barcode readers; however, only the authorized receiver can further reveal the secret from the QR code directly. The new mechanism can convey a larger secret payload along with adjustment of the QR version and error correction level. Moreover, the blind property allows the receiver to reveal the secret without the knowledge of the embedded position of modules. Experimental results demonstrate that the new algorithm is secure, efficient and feasible for the low-power QR readers and mobile devices.

• 한국ITS학회 논문지
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• 제9권5호
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• pp.87-95
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• 2010

도시의 많은 교량 구조물은 내구연한 및 노후 상태에 따라 외형적 변형이 발생하고, 지진과 태풍 등은 노후 시설물의 변형을 더욱 악화시키고 있다. 불규칙하고 미세한 점진적 외형 변형은 육안으로 확인하기 어렵고, 시설물의 성능을 저하시키게 된다. 따라서 최근에 교량 구조물의 이상 거동을 실시간의 무선 방식으로 검지하는 기술이 연구되고 있다. 본 연구는 자이로스코프를 이용하여 구조물의 미소한 물리적 변화량을 실시간으로 측정하는 변위측정모듈을 개발하였다. 개발된 계측 모듈의 성능은 시뮬레이션 실험을 통해 검증하였다.

• 정보처리학회논문지C
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• 제11C권1호
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• pp.109-114
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• 2004

본 논문에서는 통신 시스템에서 발생하는 에러를 정정 및 검출하기 위한 새로운 부호와 그 복호 방식을 제안하였다. 데이터 0의 런 길이를 제한하고 데이터 1의 최소 밀도를 증가시키기 위하여 (15, 7) BCH 부호를 변형하였으며 전체 패리티 비트를 추가하였다. 제안된 부호는 (16, 7) 블록 부호이며 비트 클럭 신호의 재생 능력과 높은 에러 제어 능력을 가지고 있다. 제안된 부호에서 데이터 0의 런 길이는 7 이하이고, 데이터 1의 밀도는 1/8 이상이며 최소 해밍 거리가 6임을 입증하였다. 제안된 부호를 사용하였을 때의 복호 에러 확률, 에러 검출 확률, 바른 복호 확률을 제시하였다. 기존의 다른 방식들에 비하여 오류 제어 능력이 우수함을 확인할 수 있었다.

• 한국IT서비스학회지
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• 제14권3호
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• pp.85-97
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• 2015

The information and communications construction business has the characteristics of an infrastructure industry and responsibility for the construction and maintenance of all ICT infrastructures. With the recent proliferation of the smart convergence of various industries based on ICT infrastructure, the role of the information and communications construction business has been highlighted to accommodate the convergence and implementation environment in construction and medical industries. Therefore, this paper seeks policy measures to establish the new role of the information and communications business under the rapidly developing smart convergence environment and the priorities of policy measures to strengthen the capability of the information and communications business using a quantitative model. The analysis result suggests that the difference in importance of each policy measure should be considered in order to execute effectively the policy of promoting the information and communications construction business. Given the constraint of limited budget, policy priorities include the development of new markets, and establishment of incentive for new technology. This study is significant for its theoretical contribution, being the first quantitative approach to policy priorities for the promotion of information and communications construction business under the smart convertgence environment.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제14권4호
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• pp.341-351
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• 2008

다수의 센서 노드들이 임의의 장소에 불규칙하게 위치하는 비정형적 환경에서의 무선 센서 네트워크에서는 일반적으로 센서 노드들이 수집한 데이타가 싱크 노드 방향으로만 전송되기 때문에 단방향이라고 할 수 있다. 이런 센서 네트워크에서는 통신이 한쪽 방향으로만 이루어지기 때문에 어떤 특이 데이타가 수신되었을 때 이에 대한 재확인 명령의 전송이 어려우며 따라서 이에 대한 사후 대책 수립이 곤란하다. 이 논문에서는 TDMA에 기반한 단방향 무선 데이타 전송 프로토콜인 WSLP(Wireless Sensor Line Protocol)을 양방향 통신이 가능하도록 확장한 BiWSLP(Biredictional WSLP)를 제안하고 이를 구현한다. 또한 제안한 BiWSLP의 기능을 평가하고 검증하기 위하여, 센서 노드를 통한 데이타 수집뿐만 아니라 노드들에게 명령을 전송하여 노드들의 동작을 제어하는 기능을 가지고 있는 가상 교량 관리 시스템을 구축하고 운영한 결과를 제시한다. 또한 가상 교량 관리 시스템을 운영 결과를 바탕으로 에너지 효율 및 양방향 통신 가능성의 관점에서 BiWSLP의 효용성을 보인다.

• 한국정보시스템학회지:정보시스템연구
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• 제2권
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• pp.194-206
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• 1993

Intelligent remote learning system is a system that incorporate communication technology and others : a database engine, an intelligent tutorial system. Learners can study by themselves through the intelligent tutorial system. The existence of a communication, database and artificial intelligence enhance the capability of IRLS. According to Parsaye, an intelligent databases should have the following features : 1) Knowledge discovery. 2) Data integrity and quality control. 3) Hypermedia management. 4) Data presentation and display. 5) Decision support and scenario analysis. 6) Data format management. 7) Intelligent system design tools. I hope that this research of framework for IRLS paves for the future research. As mentioned in the above, the future work will include an intelligent database, self-learning mechanism using neural network.

• Applied Science and Convergence Technology
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• 제27권1호
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• pp.5-8
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• 2018

In this paper, plasma treatment effects on a ploy(dimethyl siloxane) substrate were analyzed for the applications of stretchable silver nanowire (Ag NWs) electrodes. The oxygen plasma treated sample shows the best performance compared to nitrogen treated and untreated samples. The lowest sheet resistance and reasonable stretching capability was achieved up to 20% strain condition without open circuit fail for the oxygen plasma treated sample.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 추계학술대회 논문집
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• pp.594-601
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• 2000

Communication Based Train Control System supports the easy maintenance ＆ management and also have the capability to send more informations than the existing one but is less expensive. Tolerance against fault/failure and reliable data transmission are very important issues with this system since it has the responsibility of man's safety. In this paper, we suggested the schemes to support the reliable transmission quality and fault safety. Also we verified through simulation.