• 한국정보통신학회논문지
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• 제14권10호
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• pp.2207-2214
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• 2010

수중에서의 통신은 해수면과 해저면 등에 의한 신호의 반사에 의해 발생한 다중경로 현상으로 신호가 왜곡되어 원활한 통신이 어렵다. 본 논문에서는 다중경로에 의해 왜곡된 수신신호로부터 채널 복호기에 입력되는 신호를 최대한 정확하게 추정하기 위하여 최대값, 평균값, LLR 방법을 이용하여 수신된 신호를 분리하는 방법을 제안한다. 채널 부호화 방법으로는 DVB-S2 규격의 LDPC(N Size=16000)를 적용하여 각각의 방법에 따른 성능을 확인하였다. 시뮬레이션 결과 제안한 기법 중 LLR을 이용한 방법이 가장 우수한 성능을 보이는 것을 확인 할 수 있다.

• 한국정보통신학회논문지
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• 제13권11호
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• pp.2465-2472
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• 2009

본 논문에서는 ARM 칩(AT91SAM7S256), UHF/RF RFID R/W 모듈(WJR7090) 및 Bluetooth통신(FB755AC)을 이용하여 UHF RFID R/W에 적합한 원거리 데이터 전송 전용단말기를 개발하였다. 개발한 UHF RHID R/W 전용 단말기는 RFID Tag값을 Tagging하고 그 값을 Bluetooth를 통해서 서버로 전송하고, 전송한 RFID Tag값을 DB와 비교하여 그 결과를 단말기에 전송하였다. 개발한 전용단말기의 성능을 입증하기 위해 성능실험을 실시하였고, 개발한 단말기의 우수성 및 송수신패킷에 대한 실험 결과를 나타내었다.

• 융합신호처리학회논문지
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• 제1권2호
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• pp.115-121
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• 2000

본 논문에서는 초고속 멀티미디어 서비스를 제공하는 차세대 무선 통신 인프라의 하나인 성층권 비행선을 사용하여 이동 통신 시스템을 구축하였을 때, Rician 페이딩과 간섭의 영향, 그리고 간섭 제거 기법들을 고려한 outage 확률에 대해 분석하고 이를 시뮬레이션 하였다. 결과로부터, 페이딩이 없을 때의 반송파 대 간섭전력비 C/I 와 페이딩 심도K 가 outage 확률에 결정적인 영향을 미친다. 즉, 일정한 C/I에 대해 K값이 클수록, 일정 K값에 대해 C/I값이 클수록 outage 확률은 낮게 나타남을 알 수있었다.

• 유통과학연구
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• 제19권12호
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• pp.91-101
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• 2021

Purpose: This study aims to explore the effects of government's value intervention messages on the prevention and control of infectious disease in the risk communication process in terms of goveremnt policy response to COVID-19 from the mismatch message perspective, and draws the relevant implicaitons. Due to the infeciton spread, some people point out that depression caused by COVID-19 is because of wrong signals of the government and infectious disease prevention and control authorities, namely value intervention messsages. Research design, data and methodology: This study examined the epidcmic situation through message deails regarding the effects of government's mismatch messages on prevention and control of infectious disease and the resulting phenomena. Results: People's lives are under serious threat overall, so the declaration of the end of COVID-19 is almost impossible unlike MERS. Economic downturn due to foreced prevention and control regulaitons of COVID-19, mistruct of social distancing, fatigue on mismatch messages, and moral hazard on the awareness of prevention and control of infectious disease are negative phenomena to risk communiaiton on COVID-19. Conclusions: This study investigated the government authorities' policy sending wrong signals due to mismatching of the reality at this point in time for infectious disease prevention and control from the risk communicaiton perspectrive.

• 한국전자통신학회논문지
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• 제18권2호
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• pp.241-250
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• 2023

본 논문에서는 적응형 초음파 빔포밍 시스템에 LMS 알고리즘을 이용하는 때에 초기치 설정이 스텝 파라미터의 여유도에 미치는 영향을 연구하였다. 이를 위하여 임의로 설정한 빔폭을 갖는 준이상 빔과 회전 빔에 대한 빔포밍에 대해서 검토하였다. 수치 실험은 초음파 빔포밍 시스템에 임의의 초기치(음원수는 임의의 수로 고정)를 설정하고, 이에 대한 스텝 파라미터의 여유도와 수렴 특성 등을 비교하였다.

• 한국정보보호학회:학술대회논문집
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• 한국정보보호학회 2006년도 하계학술대회
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• pp.329-333
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• 2006

New computing paradigm in ubiquitous computing environments is revolutionizing the way people interact with computers, services and the surrounding physical spaces. In order to provide stronger authentication, MIST proposed an authentication framework for ubiquitous computing environments and assigned confidence values to some authentication methods to facility the combining. However, the assigned confidence values lack sufficient evidence. In this paper reliable confidence values for each authentication method used in MIST is proposed. These confidence values can combine multiple confidence values in some manner, producing a more accurate net confidence value. Authentication entities with confidence values allows the authentication framework to blond nicely into ubiquitous computing environments.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.297-299
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• 2002

This paper is proposed maximum torque control for electric vehicle drive. At low speeds, the reluctance torque is used to maximize the output for a given current level. This Is achieved maximum torque per ampere(MTPA) by selecting an optimal value of the direct stator current component. At high speeds, the system reaches a point at which the inverter will not be able to supply the desired voltage In this case it Is necessary to make use of an increased value the direct current component. The proposed control algorithm is applied to PMSM drive system, the operating characteristics controlled by maximum torque control are examined in detail by simulation.

• 수산해양교육연구
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• 제23권3호
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• pp.486-502
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• 2011

The purpose of this study is to investigate the model of curriculum supervision that can substantialize the educational value by studying actual condition and problems of present curriculum supervision. And this study focuses on reciprocal actions based on communication and dialogs. As the model of supervision mentioned above, this research proposes the supervision model of curriculum based on narrative. We need to move the view point of bureaucratic administrative supervision to new vision. For the supervision matched with this new approach, the teachers' experience has to be reinforced by dialogs and communication between school members and the person in charge of supervision in the mood of respect. The educative value of school can be recovered by the narrative through interaction, respecting school members' experience and meanings in their life according to personal practical knowledge based on teacher's experience, forming the school community by mutual communication, and constructing school culture coping with change of new environment.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2016년도 추계학술대회 논문집
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• pp.33-34
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• 2016

This paper presents a load sharing method based on the low bandwidth communication (LBC) applied to a DC microgrid in order to balance the state of charge (SOC) of the battery units connected in parallel to the common bus. In this method, SOC of each battery unit is transferred to each other through LBC to calculate average SOC value. After that, droop coefficients of battery units are adjusted according to the difference between SOC of each unit and average SOC value of all batteries in the system. The proposed method can effectively balance the SOC of battery units in charging and discharging duration with a simple low bandwidth communication system.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.97-100
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• 1996

In this paper, 3-terminal EMI filter for communication was studied. EMI filter for communication combining Ferrite bead with 3-terminal capacitor was constructed with T-type. We was able to control resonance frequency with chip capacitor value and attenuation characteristics by Ferrite bead properties.