• 한국정보과학회:학술대회논문집
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• 한국정보과학회 1998년도 가을 학술발표논문집 Vol.25 No.2 (3)
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• pp.293-295
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• 1998

ATM over xDSL으로 구성된 광대역 가입자 망을 통하여, ATM마에 접속하려 할 때에는 DSL접근 다중화기 (Access Multiplexer )가 필수적으로 요구된다. 이때 관대역 통합서비스라는 가입자가 망의 기본적인 목적을 달성하기 위하여, DSL접근 다중화기는 ATM？ㅇ에서 트래픽 제어를 수행할 수 있어야 한다. 이에 본 논문에서는 DSL접근 다중화가에서는 트래픽 제어에 필요한 효율적이고 간단한 셀 스케줄링 기법을 제안한다. 성능 평가를 위한 모의 실험에 의하면 제안된 기법은 각 연결들의 트래픽 기술자에 부합하는 서비스를 제공할 수 있으며, 아울러 연결들이 명세한 셀 손실률에 근거한 차별화된 서비스 품질 (QoS)을 제공할 수 있다.

• ETRI Journal
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• 제32권6호
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• pp.961-964
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• 2010

This letter introduces a stereoscopic video broadcasting system that provides 3D visual service and has full backward compatibility with legacy digital television (DTV) service in the same channel capacity. The proposed stereoscopic video broadcasting system in this letter is composed of both a hybrid codec and a multiplexer with a newly defined stereoscopic-related signaling method. In conclusion, the proposed method can be effectively applied for 3D broadcasting services without major changes in legacy broadcasting platforms.

• 한국초전도ㆍ저온공학회논문지
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• 제20권1호
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• pp.11-14
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• 2018

High Temperature Superconducting (HTS) power cables are capable of transmitting bulk power without any loss compared to conventional copper cables. The major challenge in the design of such HTS cables is the high stresses (electro-thermal/electro-mechanical) developed at high voltages, high currents and cryogenic temperatures. The safe and reliable operation of HTS cables involves lots of instrumentation for monitoring, measurement, control and safe operation. In principle, a four probe method for resistance (RTD PT-100) is used for temperature measurements at various locations of HTS cable. The number of connecting leads required for this is four times that of the number of sensors. The present paper discusses a novel way of connecting 128 RTD sensors with the help of only 14 leads using a cold electronics based multiplexer board. LabVIEW 11.0 software was used for interfacing and displaying the readings of all the sensors on computer screen.

• ETRI Journal
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• 제10권1호
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• pp.3-13
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• 1988

With the contunuing trends towards an information based society, telecommunications services are becoming an integral part of social activities. So, emphasis on ISDN is growing rapidly and placed on supporting integrated services delivery of different levels to the end user. The end user’s perception of an integraged services delivery(in particular, ISDN services) should reflect three interrelated capabilities, ISDN access capabilities and ISDN network capabilities. For turning the ISDN concept of above capabilities into reality, we have implemented the experimental system on user-network interfaces, which are three kinds of implementations in user access arrangements, namely basic access, intermediate rate multiplexed access and primary rate multiplexed access. Through these implementations, NTE(Network Terminating Equipment) is used for single basic access [2B+D], IMUX (Intermediate rate Multiplexer) for 4 basic accesses [4X(2B+D)] and PMUX(Primary rate Multiplexer) for [10/12 X (2B+D)]. This paper describes the outlines of system features on user access equipments, system architectures of testbed and experiment result of each access arrangements.

• 한국통신학회논문지
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• 제24권7B호
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• pp.1220-1228
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• 1999

이 연구는 멀티미디어 서비스를 제공하는 중요한 망 설계 문제를 다룬다. 이 연구에서 다루는 문제는 게이트웨이 위치와 광케이블 경로를 정하는 문제로서 가능한 한 총비용을 최소화하는 소넷링을 설계한다. 고려하는 비용은 게이트웨이와 전화국에 설치되는 가감 다중화기(Add-Drop Multiplexer)의 설치비용과 광케이블의 선로 비용이다. 이를 해결하기 위하여 먼저 최적화모형을 제시하고, 효율적인 해법으로서 몇 가지 휴리스틱 방법을 개발한다. 몇 가지 예제를 수행한 결과는 두 해법의 총비용 절감 효과를 보여준다.

• 한국경영과학회지
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• 제24권3호
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• pp.83-91
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• 1999

In order to build and manage an ATM network effectively under several types of control methods, it is necessary to estimate the performance of the equipments in various viewpoints, especially of ATM multiplexer. As for the method to model the input stream into the ATM multiplexer, many researches have been done to characterize it by, such as, fluid flow, MMPP(Markov Modulated Poisson Process), or MMDP (Markov Modulated Deterministic Process). We introduce an MRP(Markov Renewal Process) to model the input stream which has proper structure to represent the burst traffic with high correlation. In this paper, we build a model for aggregated heterogeneous ON-OFF sources of ATM traffic by MRP. We make discrete time MR/D/1/B queueing system, whose input process is the superposed MRP and present a performance analysis by finding CLP(Cell Loss Probability). A simulation is done to validate our algorithm.

• 한국경영과학회지
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• 제23권4호
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• pp.97-109
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• 1998

In this paper, we propose a new approach to solve stochastic fluid flow models applied to the analysis of ceil loss of an ATM multiplexer. Existing stochastic fluid flow models have been analyzed by using linear differential equations. In case of large state space, however. analyzing stochastic fluid flow model without numerical errors is not easy. To avoid this numerical errors and to analyze stochastic fluid flow model with large state space. we develope a new computational algorithm. Instead of solving differential equations directly, this approach uses iterative and numerical method without calculating eigenvalues. eigenvectors and boundary coefficients. As a result, approximate solutions and upper and lower bounds are obtained. This approach can be applied to stochastic fluid flow model having general Markov chain structure as well as to the superposition of heterogeneous ON-OFF sources it can be extended to Markov process having non-exponential sojourn times.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2013년도 하계학술대회
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• pp.93-96
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• 2013

증강방송(Augmented Broadcasting)은 최근 스마트 기기의 보급으로 인해 대중적으로 알려진 증강현실(Augmented Reality) 서비스를 스마트 TV 와 같은 하이브리드 방송 환경에 접목하여, 시청자에게 기존에 느낄 수 없었던 TV 시청에 대한 몰입감과 콘텐츠 조작의 양방향성을 제공하고자 하는 새로운 방송통신 융합 서비스 개념이다. 증강방송에 대한 개념과 PC 기반의 테스트베드 시스템은 이미 다수 발표되었으며, 본 논문에서는 디지털 지상파 방송 환경에서의 증강방송 시스템 실현을 위해 DTV 기반의 증강방송 시그널링과 콘텐츠 동기화 방안을 적용한 재다중화기(Re-multiplexer)의 설계 및 구현에 관해 설명한다.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1995년도 춘계공동학술대회논문집; 전남대학교; 28-29 Apr. 1995
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• pp.435-444
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• 1995

We propose a new approach to the calculation of the exact cells loss probability in a shared buffer ATM multiplexer, which is loaded with homogeneous discrete-time ON-OFF sources. Renewal cycles are identified in regard to the state of input sources and the buffer state on each renewal circle is modelled as a K(shared buffer size)-state Markov chain. We also analyze the behavior of queue build-up at the shared buffer whose distribution together with the steady-state probabilities of the Markov chain leads to the exact cell loss probability. Our approach to obtaining the exact cell loss probability seems to be more efficient than most of other existing ones since our underlying Markov chain has less number of states.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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• pp.543-546
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• 1996

Recently, some research has been done to analyze the asymptotic behavior of queue length distribution in ATM (Asynchronous Transfer Mode) multiplexer. In this paper, we relate this asymptotic behavior with the asymptotic behavior of decreasing cell loss probability when the buffer capacity is increased. We find with reasonable assumptions that the asymptotic rate of queue length distribution is the same as that of decreasing cell loss probability. Even under different priority control schemes and traffic classes, we find that this asymptotic rate of the individual cell loss probability of each traffic class does not change. As a consequence, we propose the upper bound of cell loss probability of each traffic class when a priority control scheme is employed. This bound is computationally feasible in a real-time. The numerical examples will be provided to validate this finding.