• ETRI Journal
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• 제32권5호
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• pp.819-822
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• 2010

Supporting QoS over multihop wireless mesh networks is difficult because end-to-end delay increases quickly with the increasing number of hops. This paper introduces a novel multichannel time-division multiple-access media access control (McTMAC) protocol that can help to efficiently reduce delay over multihop networks. Performance evaluation results demonstrate that McTMAC outperforms existing alternative protocols. The max-delay can be reduced by as much as 60% by using McTMAC.

• 정보과학회 논문지
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• 제44권1호
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• pp.36-43
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• 2017

의미역 결정 연구에 있어 구문 분석 정보는 술어-논항 사이의 의존 관계를 포함하고 있기 때문에 의미역 결정 성능 향상에 큰 도움이 된다. 그러나 의미역 결정 이전에 구문 분석을 수행해야 하는 비용(overhead)이 발생하게 되고, 구문 분석 단계에서 발생하는 오류를 그대로 답습하는 단점이 있다. 이러한 문제점을 해결하기 위해 본 논문에서는 구문 분석 정보를 제외한 형태소 분석 정보만을 사용하는 End-to-end SRL 방식의 한국어 의미역 결정 시스템을 제안하고, 순차 데이터 모델링에 적합한 LSTM RNN을 확장한 Stacked Bidirectional LSTM-CRFs 모델을 적용해 구문 분석 정보 없이 기존 연구보다 더 높은 성능을 얻을 수 있음을 보인다.

• 한국해양공학회지
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• 제19권6호통권67호
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• pp.1-7
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• 2005

This paper deals with the design and aerodynamic analysis of a special-type impulse turbine, with an end plate for wave energy conversion. Numerical analysis was performed using a CFD code, FLUENT. The main idea of the proposed end plate was to minimize the adverse effect of tip clearance of turbine blade, and was borrowed from ducted propeller, with so-called penetrating end plate for special purpose marine vehicles. Results show that efficiency increases up to $5\%$, depending on the flow coefficient; a higher flow coefficient yields increased efficiency. Decrease of input coefficient CAwith an end plate is the main reason for higher efficiency. Performance of end plate at various design parameters, as well as flow conditions, was investigated; the advantages and disadvantages of the presentimpulse turbine were also discussed.

• 한국강구조학회 논문집
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• 제28권6호
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• pp.427-438
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• 2016

두본 연구는 실험적인 방법을 통하여 단부판 이음부의 이음면에서 초기 오차로 발생하는 이격이 이음부의 내력 및 거동에 미치는 영향을 평가한 연구이다. 이를 위하여 총 5가지의 단순보형 실험체를 확장형 단부판 이음부를 이용 계획하였고 주요 변수로는 이음면 초기 이격(gap) 여부, 고력볼트 채결 전 끼움판(finger shim plate) 설치 유무, 고력볼트 체결 후 이음면 이격, 고력볼트 채결 후 끼움판 삽입 여부를 적용하였다. 정적가력실험 결과 이음판의 이격은 이음부의 최대휨강도에 미치는 영향은 제한적이나 수직변형과 초기 및 탄성강성에는 영향을 미치는 것으로 나타났으며, 이격을 제어하기 위해 고력볼트 장력을 이용할 경우 고력볼트의 취성파괴 우려도 있는 것으로 나타나서 이들에 대한 충분한 고려가 필요할 것으로 판단된다.

• 한국통신학회논문지
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• 제24권10B호
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• pp.1852-1860
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• 1999

본 논문에서는 음성 패킷을 전송하기 위해 새로 제시되어 표준화된 AAL2의 성능을 이산 시간 시뮬레이션 모형(discrete-time simulation model)을 통해 분석하였다. 시뮬레이션의 입력 파라메터로는 AAL2 PDU를 만들기 위한 패킷 필 지연 시간(packet fill delay), 여러 AAL2 PDU로부터 ATM 셀을 만들기 위한 셀 생성 지연(guard time), 음성 트래픽의 특성을 정의하는 버스트 정도(burstness), 그리고 사용자 수(number of channels)로 하였으며 이 값의 변화에 따른 음성 패킷의 양종단 지연 시간 변이(end-to-end delay variation)을 계산하여 각각의 파라미터가 음성 패킷의 성능에 미치는 영향을 분석하였다.

• Journal of Information Technology Applications and Management
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• 제11권3호
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• pp.117-135
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• 2004

The purpose of this research is to examination whether End-User Computing relative factors are ap-plied in Computer Assisted Reporting. Computer Assisted Reporting is closely related to End-User Computing, because IT and IS be used by reporting for data gathering and analysis. For the purpose, we've produced a survey, and then studied the effects of the use of Computer Assisted Reporting tools on the report's satisfaction and job performance. As a result, The degree of use of Computer Assisted Reporting significantly affects the degree of satisfaction and job performance. for this reason, this research can give an insight for the extension of End-User Computing relative research.

• Journal of Communications and Networks
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• 제9권3호
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• pp.229-235
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• 2007

This paper analyzes the performance of a Bluetooth piconet in error-prone environments. A statistical characterization of a waiting time, an end-to-end delay, and a goodput are derived analytically in terms of the arrival rates, the number of slaves, and the packet error rate (PER). For simplicity, half-symmetric piconet is assumed in this analysis. Both exhaustive and limited scheduling are considered. The analytic results are validated by simulations.

• ETRI Journal
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• 제45권1호
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• pp.18-27
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• 2023

We present an English-Korean speech translation corpus, named EnKoST-C. End-to-end model training for speech translation tasks often suffers from a lack of parallel data, such as speech data in the source language and equivalent text data in the target language. Most available public speech translation corpora were developed for European languages, and there is currently no public corpus for English-Korean end-to-end speech translation. Thus, we created an EnKoST-C centered on TED Talks. In this process, we enhance the sentence alignment approach using the subtitle time information and bilingual sentence embedding information. As a result, we built a 559-h English-Korean speech translation corpus. The proposed sentence alignment approach showed excellent performance of 0.96 f-measure score. We also show the baseline performance of an English-Korean speech translation model trained with EnKoST-C. The EnKoST-C is freely available on a Korean government open data hub site.

• 한국유체기계학회 논문집
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• 제16권1호
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• pp.5-10
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• 2013

The performance of screw air compressor is affected by rotor profile, lobe number, air end wrap angle, rotor L/D ratio, suction and discharge ports, revolutions of air end and load regulation control, etc. In general, an efficient screw compressor needs a rotor profile of which has a large flow cross-section area, short sealing lines and a small blow-hole. In this study, experimental study was performed with newly designed $5{\times}6$ rotor profile and various shapes of air end. Results show that the measured specific power consumption of the newly designed screw compressor appeared to be lower than any other published data for the equivalent screw compressors manufactured.

• Journal of electromagnetic engineering and science
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• 제8권3호
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• pp.114-118
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• 2008

Direct-conversion RF front-end for 5-GHz WLAN is implemented in $0.18-{\mu}m$ CMOS technology. The front-end consists of a low noise amplifier, and low flicker noise down-conversion mixers. For the mixer, an inductor is included to resonate out parasitic tail capacitances in the transconductance stage at the operating frequency, thereby improves the flicker noise performance of the mixer, and the overall noise performance of the front-end. The receiver RF front-end has 6.5 dB noise figure, - 13 dBm input IP3, and voltage conversion gain of 20 dB with the power consumption of 30 mW.