• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.811-814
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• 2009

The HF band maritime communication is have developing to digital methode that techniques should be readied the automatic link establishment of 1:N by coast station to many ship station. Because can use way by polling simply that communication environment calls particular station wicked fellow HF communication states which is much redundancy times for coast station to set link. In amateur radio particular station selective calling do to be using ALE(Automatic Link Establishment) controller by 1:1 automatic link setting way, but expect 1:N link setting by these way in maritime communication very difficult. That is difficult to avoid collision by traffic overload to induce calling of ship stations. Because HF communication considers channel special quality traffic state radio link should be established, and should be applied automatically secures stability of channel as accommodative at traffic overload. In this paper is studied the new radio protocol by 3 step sequency driving of free access, group free access and polling access using multi-tone in single channel.

• Phonetics and Speech Sciences
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• v.11 no.3
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• pp.39-47
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• 2019

We propose a method to improve the performance of spontaneous speech recognizers by extending their phone set using speech data. In the proposed method, we first extract variable-length phoneme-level segments from broadcast speech signals, and convert them to fixed-length latent vectors using an long short-term memory (LSTM) classifier. We then cluster acoustically similar latent vectors and build a new phone set by choosing the number of clusters with the lowest Davies-Bouldin index. We also update the lexicon of the speech recognizer by choosing the pronunciation sequence of each word with the highest conditional probability. In order to analyze the acoustic characteristics of the new phone set, we visualize its spectral patterns and segment duration. Through speech recognition experiments using a larger training data set than our own previous work, we confirm that the new phone set yields better performance than the conventional phoneme-based and grapheme-based units in both spontaneous speech recognition and read speech recognition.

• Photonics industry news
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• s.7
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• pp.54-59
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• 2001

본지에서는 한국과학기술정보연구원(KISTI)의 자료협조를 받아 광산업과 관련된 해외 신기술 동향을 소개한다.

• Proceedings of the Optical Society of Korea Conference
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• 2001.08a
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• pp.94-95
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• 2001

• Proceedings of the Optical Society of Korea Conference
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• 2001.08a
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• pp.96-97
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• 2001

• Proceedings of the Korean Nuclear Society Conference
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• 1999.10a
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• pp.380.2-380
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• 1999

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.110.2-110.2
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• 2016

4세대 방사광가속기는 0.1nm급 X-선 자유전자레이저(X-ray Free Electron Laser : XFEL) 광원을 빔라인 사용자들에게 제공하기 위하여 2011년 건설을 시작하였고, 2015년부터 장치를 설치하기 시작했으며 현재 건설 완료단계에 이르러 있다. 이 장치에서 진공시스템은 10-11 mbar의 초고진공이 요구되는 전자빔 발생장치인 RF Gun을 포함하는 입사장치구간(Injector)과 전체길이 800 m에 이르는 전자빔을 가속시키는 선형가속기구간(Linac) 그리고 결맞음 방사광을 발생시키는 언듈레이터구간으로 나눌 수 있다. 본 논문에서는 각 구간별 진공시스템에 대한 건설 현황에 대하여 보고하고자 한다.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.132-133
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• 2007

자성유체의 전자기력에 의한 거동 파악을 위해 전자기 체적력에 의한 접근법을 제안한다. 정유체역학식에 수정 된 Kelvin 가진력식이 도입되며, 유체표면에서의 압력이 일정하여야 한다는 원리에서 유체 표면의 형상을 얻어낼 수 있다.

• Broadcasting and Media Magazine
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• v.27 no.3
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• pp.11-24
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• 2022

COVID-19로 급부상한 메타버스는 현실 세계의 활동을 가상세계로 확장하여 접근하는 방식을 제시함으로써, 서비스 사업자들에게 현실의 자산이나 가치를 가상 공간에서 새로운 자산과 가치로 재해석하여 새로운 창조적 생태계를 선도할 수 있는 자유도와 기회를 제공하고, 사용자들에게는 이를 통해 서비스의 접근성과 지속성 및 새로운 욕구를 충족할 수 있는 기회를 제공함으로써 관심을 받게 되었다. 본 기고에서는 미래 메타버스 생태계의 새로운 기회를 제공할 DAO와 Web 3.0 관련 동향을 점검하고 탈중앙화의 미래 가능성과 문제점을 논한다.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.5
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• pp.372-379
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• 2017

Software reliability factor during the software development process is elementary. Case of the infinite failure NHPP for identifying software failure, the occurrence rates per fault (hazard function) have the characteristic point that is constant, increases and decreases. In this paper, we propose a reliability model using the chi - square distribution which depends on the degree of freedom that represents the application efficiency of software reliability. Algorithm to estimate the parameters used to the maximum likelihood estimator and bisection method, a model selection based on the mean square error (MSE) and coefficient of determination($R^2$), for the sake of the efficient model, were employed. For the reliability model using the proposed degree of freedom of the chi - square distribution, the failure analysis using the actual failure interval data was applied. Fault data analysis is compared with the intensity function using the degree of freedom of the chi - square distribution. For the insurance about the reliability of a data, the Laplace trend test was employed. In this study, the chi-square distribution model depends on the degree of freedom, is also efficient about reliability because have the coefficient of determination is 90% or more, in the ground of the basic model, can used as a applied model. From this paper, the software development designer must be applied life distribution by the applied basic knowledge of the software to confirm failure modes which may be applied.