구조물의 진동제어를 위한 양방향 무선통신시스템 설계

허광희(Heo, Gwanghee),김충길(Kim, Chunggil),전준용(Jeon, Joonryong),오주원(Oh, Juwon) 한국구조물진단유지관리학회 2010 한국구조물진단학회 학술발표회논문집 Vol.2010 No.1

This research aims to develop a system of wireless bidirectional communication between structure and a maintenance host as a preceding process eventually for the development of a system of unified wireless control for structural vibration which is made to acquire data from the structure and transmit them wirelessly to the main control system. For the purpose, all different types of data are made possible to be obtained by a unified wireless measurement system, and also a main control system is built to manage the unified wireless measurement system itself, and monitor and preserve the data. As for its performance, it is confirmed by means of various kinds of measuring appliance that data are successfully transmitted wirelessly and bidirectionally. Finally, it is also proven that the wireless bidirectional communication system would directly contribute to the development of a system of unified wireless control for structural vibration in the future.

구조물의 진동제어를 위한 양방향 무선통신시스템 설계

허광희 ( Heo Gwanghee ),김충길 ( Kim Chunggil ),전준용 ( Jeon Joonryong ),오주원 ( Oh Juwon ) 한국구조물진단유지관리공학회 2010 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.14 No.1

This research aims to develop a system of wireless bidirectional communication between structure and a maintenance host as a preceding process eventually for the development of a system of unified wireless control for structural vibration which is made to acquire data from the structure and transmit them wirelessly to the main control system. For the purpose, all different types of data are made possible to be obtained by a unified wireless measurement system, and also a main control system is built to manage the unified wireless measurement system itself, and monitor and preserve the data. As for its performance, it is confirmed by means of various kinds of measuring appliance that data are successfully transmitted wirelessly and bidirectionally. Finally, it is also proven that the wireless bidirectional communication system would directly contribute to the development of a system of unified wireless control for structural vibration in the future.

클록 데이터 복원 회로가 없는 보조채널을 이용한 양방향 통신

유병재,조현묵 한국소프트웨어감정평가학회 2018 한국소프트웨어감정평가학회 논문지 Vol.14 No.2

As the data transmission speed increases, the source transmits the clock and data together, and the CDR(Clock Data Recovery) of the sink restores the clock Some communication schemes include unidirectional channels that transmit data from sink to source, or bidirectional channels between source and sink. However, the bidirectional channel transmits data at a relatively low speed as compared with the unidirectional channel, and additional circuitry is required to separately generate the transmission clock. In this paper, we propose a new bidirectional communication method that does not require a CDR circuit to recover the transmitted data from the source using the clock recovered from the sink. As a result, it becomes possible to utilize a unidirectional channel as a bidirectional channel without increasing the additional circuit area and power consumption at the source.

스페인어 스마트교육과 면대면 양방향 커뮤니케이션사이의 상보성

마상영 서울대학교 라틴아메리카연구소 2015 이베로아메리카硏究 Vol.26 No.3

In this paper I have clarified the existence of the complementarity between the Spanish Smart education and the face-to-face bidirectional communication, contending that if we use it efficiently, we canmake the efficiency of Spanish education higher in a large measure. The Spanish education through the bilateral communication, based on the complementary use of the respective advantages of the Smart education and the on-site classes helps us to join their strong points countervailing their weak points and to practice a perfect and efficient education. If the face-to-face bidirectional communication between the professor and the students is achieved, the professor can discern the unforeseeable inconveniences of the students, minimize them and practice the education focused not on his will but on theirs. The change of this education system brings too the role change between the professor and his students, and enhances the learning efficiency. In conclusion, the Spanish education through the face-to-face bidirectional communication should be based on the Blended Education that compensates the advantages and disadvantages of the Smart education and the on-site education, and it can make us practice the best education in accordance with the learning situation, the students’ levels and the types of contents. 본 논문에서 필자는 스페인어 스마트교육과 면대면 양방향 커뮤니케이션 사이에 상보성이 존재하고 있음을 규명하였고, 그러한 상보성을 효율적으로 활용한다면, 스페인어 교육의 효율성을 크게 상승시킬 수 있음을 주장하였다. 스마트교육과 현장교육의 장점들을 상보적으로활용하는 환경 하에서 이루어지는 양방향 커뮤니케이션을 통한 스페인어교육은 각각의 단점들을 상쇄시키고 장점들을 통합하여 보다 효율성 높은 교육을 할 수 있게 해 준다. 만약 교수자와 학습자 사이에 면대면 양방향 커뮤니케이션이 이루어지면, 교수자는 예견하지 못했던 학습자의 어려움들을 파악할 수 있고, 그것들을 최소화 하고 나아가 교수자가 아닌 학습자 중심의교육을 실현할 수 있다. 이러한 교육 시스템의 변화는 또한 교수자와 학습자 사이의 역할 변화를 낳게 하고, 궁극적으로 학습효율도 증대시키게 된다. 요약하면, 양방향 커뮤니케이션을 통한 스페인어 교육은 스마트교육과 현장교육의 장점들을 취합하고 단점들을 상쇄시키는 상보적인 융합교육 방식에 기반을 두고 있으며, 학습 환경, 학습자의 수준 그리고 학습 콘텐츠의 유형에 따라 최적의 교육을 실현할 수 있게 해 준다.

Adaptive Cooperation for Bidirectional Communication in Cognitive Radio Networks

( Yuan Gao ),( Changping Zhu ),( Zhixiang Deng ),( Yibin Tang ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.3

In the interweave cognitive networks, the interference from the primary user degrades the performance of the cognitive user transmissions. In this paper, we propose an adaptive cooperation scheme in the interweave cognitive networks to improve the performance of the cognitive user transmissions. In the proposed scheme for the bidirectional communication of two end-source cognitive users, the bidirectional communication is completed through the non-relay direct transmission, the one-way relaying cooperation transmission, and the two-way relaying cooperation transmission depending on the limited feedback from the end-sources. For the performance analysis of the proposed scheme, we derive the outage probability and the finite-SNR diversity multiplexing tradeoff (f-DMT) in a closed form, considering the imperfect spectrum sensing, the interference from the primary user, and the power allocation between the relay and the end-sources. The results show that compared with the direct transmissions (DT), the pure one-way relaying transmissions (POWRT), and the pure two-way relaying transmissions (PTWRT), the proposed scheme has better outage performance. In terms of the f-DMT, the proposed scheme outperforms the full cooperation transmissions of the POWRT and PTWRT.

Near Real-time M2M Communication for Bidirectional AMR Systems

Kwang-il Hwang,Sung-wook Nam 한국정보기술융합학회 2014 JoC Vol.5 No.2

무선시스템을 이용한 구조물 진동제어시스템 설계

허광희(Heo, Gwanghee),김충길(Kim, Chunggil),전준용(Jeon, Joonryong),오주원(Oh, Juwon),전승곤(Jeon, Seunggon) 한국구조물진단유지관리학회 2010 한국구조물진단학회 학술발표회논문집 Vol.2010 No.2

This paper aims to design a wireless control & communication system for the control of structural vibration and prove its functional effectiveness. This system is composed of a wireless measurement system acquiring the response of structure and a control system which analyzes the response signals of structure and thus controls the structural vibration. Essentially it as a central administration manages and controls the overall system. Also it wirelessly transmits data. In order to prove the effectiveness of the wireless control & communication system, the functions of analogy input and analogy output were verified. Especially the experiments for the test of analogy input and analogy output were performed ten times under each different condition. The comparison of the data from the experiments with those of a wired measurement system proved its outstanding effectiveness. It was thus found that the wireless control & communication system developed in this research would possibly control the vibration with the feedback signals after sending out proper output signals to the vibration control of structure.

Wavelength reused bidirectional reflective coherent-PON based on cascaded SOA/RSOA ONUs

Jung, Sang-Min,Mun, Kyoung-Hak,Kang, Soo-Min,Han, Sang-Kook Elsevier 2018 Optical fiber technology Vol.45 No.-

<P><B>Abstract</B></P> <P>This paper demonstrates wavelength reused bidirectional transmission for a reflective coherent passive optical network (R-Co-PON). By reusing the downstream optical signal as the upstream optical carrier, the proposed R-Co-PON enhances the optical spectral efficiency. In an experimental demonstration, the proposed R-Co-PON achieved a symmetrical bidirectional transmission rate of 12 Gb/s using a 73-km-long fiber loopback architecture. The experiments confirmed the potential applicability of the proposed system in future optical access networks, particularly those using wavelength-division multiplexing.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Wavelength reuse based bidirectional coherent OFDMA access network. </LI> <LI> Enhancement of spectral efficiency by using the proposed reflective coherent PON. </LI> <LI> Verification of the proposed technique in future WDM-PON. </LI> </UL> </P>

양방향 다중직렬통신을 위한 이중전압 직류 전력선 통신 드라이버 구현

한경호(Kyong-Ho Han),황하윤(Ha-Yoon Hwang) 한국조명·전기설비학회 2009 조명·전기설비학회논문지 Vol.23 No.10

본 논문에서는 두 가지 전압을 이용하여 직류 전력선을 이용한 양방향 다중직렬통신 드라이버의 구현과 이를 위한 소형화 회로 설계에 대하여 다룬다. 다중접속통신은 호스트에 고유의 ID를 갖는 여러 개의 클라이언트와 패킷에 의한 데이터 전송을 행한다. 양방향 통신을 위하여 호스트에서 데이터 1/0이 전송될 경우, 각 경우에 24[V]/12[V]전원을 선택하며 클라이언트가 데이터를 전송할 때, 호스트는 통신선로의 전압을 감지하여 전송하는 데이터에 따라, 24[V]/12[V]전원을 선택한다. 이러한 기능을 구현하는 소형 드라이버 회로를 설계, 제작하여 호스트와 클라이언트의 직렬 통신 포트에 접속하였으며, 하나의 호스트와 여러 개의 클라이언트로 네트워크을 구현하고 실험에 의하여 직류 전력선을 이용한 양방향 직렬통신의 기능을 확인하였다. This paper handles, implementation of multiple access bidirectional serial communications protocol using DC power lines. The normal voltage of the power communication line maintains 24[V] corresponding to level 1 and the host drops the voltage to 12[V] on sending level 0 signal, also the clients normally keeps the line voltage to 24[V] use pull-down circuit to drop the voltage to 12[V] on sending level 1 signal. Host senses the voltage level of the power communication lines and the hosts switches power source from 24[V] to 12[V]. Experimental circuit is designed with one hosts and four clients and verified the power line voltage switching operation depending on the data signal levels on the power line.

여러 사용자 양방향 통신을 위한 MMSE-기반 중계 기법

정진곤,Joung, Jin-Gon 한국통신학회 2009 韓國通信學會論文誌 Vol.34 No.5a

본 논문에서는 평균제곱오차(mean-square-error)를 최소화하며, 여러 사용자 양방향 통신(bidirectional communications)을 지원하는, 증폭-후-전달(amplify-and-forward) 중계기의 송수신 가중치 행렬을 제안한다. 또한, 시스템 전송량을 최대화하는 각 사용자 빔포밍(beamforming) 벡터를 설계한다. 모의실험을 통해 제안한 중계기 가중치로 여러 사용자간 상호채널간섭(co-channel interference)과 양방향 통신에서 발생하는 자기간섭(self-interference)을 효과적으로 줄일 수 있음을 보이고, 또한, 제안한 빔포밍 방식이 공간 다중화(spatial multiplexing) 방식에 비해 증폭-후-전달 중계기 양방향 통신에 적합함을 확인하였다. In this paper, minimum mean-square-error (MMSE)-based transceiver processing of a bidirectional amplify-and-forward (AF) relay having multiple antennas is proposed. Besides, the optimal beamforming vectors of users are designed in the sense of the sum rate maximization. Simulation results show that the proposed relay processing can effectively reduce both co-channel interferences and self-interferences and that the proposed beamforming method is proper to the bidirectional communication employing the AF relay.