• 한국통신학회논문지
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• 제21권2호
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• pp.534-540
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• 1996

This paper presents an Adaptive Time-Delay Recurrent Neural Network (ATRN) for learning and recognition of temporal correlations of temporal patterns. The ATRN employs adaptive time-delays and recurrent connections, which are inspired from neurobiology. In the ATRN, the adaptive time-delays make the ATRN choose the optimal values of time-delays for the temporal location of the important information in the input parrerns, and the recurrent connections enable the network to encode and integrate temporal information of sequences which have arbitrary interval time and arbitrary length of temporal context. The ATRN described in this paper, ATNN proposed by Lin, and TDNN introduced by Waibel were simulated and applied to the chaotic time series preditcion of Mackey-Glass delay-differential equation. The simulation results show that the normalized mean square error (NMSE) of ATRN is 0.0026, while the NMSE values of ATNN and TDNN are 0.014, 0.0117, respectively, and in temporal learning, employing recurrent links in the network is more effective than putting multiple time-delays into the neurons. The best performance is attained bythe ATRN. This ATRN will be sell applicable for temporally continuous domains, such as speech recognition, moving object recognition, motor control, and time-series prediction.

• 전자공학회논문지C
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• 제36C권12호
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• pp.59-68
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• 1999

ASIC의 타이밍 특성 분석은 회로를 구성하는 게이트와 이들을 연결하는 배선의 지연 시간을 바탕으로 이루어진다. 게이트의 지연 시간은 입력에 인가된 파형의 천이 시간과 출력에 연결된 부하 커패시턴스를 변수로 하는 이차원 테이블로 모델링할 수 있다. 배선의 지연 시간은 배선에서 추출한 저항, 커패시턴스 등으로 구성된 배선회로에 AWE 기법을 적용하여 계산할 수 있다. 그러나 이들 지연 시간은 구동 게이트와 배선의 상호 작용의 영향을 받으므로 이 효과를 반영하여 이차원 테이블 모델과 AWE 기법을 사용하여야 한다. 배선을 구동하는 게이트가 한 개라는 가정 하에서 유효 커패시턴스와 게이트 구동 모델을 통하여 상호 작용을 고려하는 기법이 제안된 바 있다. 본 논문은 이를 확장하여 병렬로 연결된 여러 개의 CMOS 게이트가 동시에 배선을 구동하는 경우를 다룰 수 있는 기법을 제시하고 있다. 이 기법을 C 프로그램으로 구현하여 CMOS ASIC 제품에 적용한 결과 , 게이트와 배선의 지연 시간을 SPICE와 비교하여 수 십 배 이상 빠른 속도와 수 % 이내의 오차로 분석하였다.

• Journal of Communications and Networks
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• 제12권4호
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• pp.308-316
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• 2010

The problem of compressed sensing (CS) based multiple access is studied under the assumption of random data traffic. In many multiple access systems, i.e., wireless sensor networks (WSNs), data arrival is random due to the bursty data traffic for every transmitter. Following the recently developed CS methodology, the technique of compressing the transmitter identities into data transmissions is proposed, such that it is unnecessary for a transmitter to inform the base station its identity and its request to transmit. The proposed compressed multiple access scheme identifies transmitters and recovers data symbols jointly. Numerical simulations demonstrate that, compared with traditional multiple access approaches like carrier sense multiple access (CSMA), the proposed CS based scheme achieves better expectation and variance of packet delays when the traffic load is not too small.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.744-747
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• 2005

The AEC (Architecture/Engineering/Construction) industry is facing a competitive world after it entered into the 21^st century. Due to improper planning and scheduling, the construction projects face severe delays in completion. Most of the present day construction organisations operate in multiple project environments where more than one projects are to be managed simultaneously. But the advantages of planning and scheduling as multiple projects have not been utilized by these organisations. Change in multi-project planning and scheduling is inevitable and often frequent, therefore the traditional planning and scheduling approaches are no more feasible in scheduling multiple construction projects. The traditional scheduling tools like CPM and PERT do not offer any help in scheduling in a resource-constrained environment. This necessitated a detailed study to model the environment realistically and to make the allocation of limited resources flexible and efficient. This paper delineates about the proactive model which will help the project managers for scheduling the multiple construction projects.

• 제어로봇시스템학회논문지
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• 제10권7호
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• pp.583-589
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• 2004

Modem control systems often use a communication network to send measurement and control signals between nodes. Communication delays can be time varying. The length of the time delays is often hard to predict and modeled as being random. This paper proposes a combined controller used to compensate network time delay by estimating the delay with the interacting multiple model (IMM). The network delay is modeled as a Markov chain and 3 modes representing heavy, medium, and low network loads are used in the IMM. The proposed method is applied to an optimal control system with double integrators and the results are compared with the existing control methods.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.915-920
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• 2003

Modern control systems often use a communication network to send measurement and control signals between nodes. Communication delays can be time varying. The length of the time delays is often hard to predict and are modeled as being random. This paper proposes a combined controller used to compensate network time delay by estimating the delay with the interacting multiple model (IMM). The network delay is modeled as a Markov chain and 3 modes representing heavy, medium, and low network loads are used in the IMM. The proposed method is applied to an optimal control system with double integrators and the results are compared with the existing control methods.

• 대한전기학회논문지
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• 제39권4호
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• pp.364-370
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• 1990

In this paper, we propose a self-tuning PID controller for unknown systems with time-varying delay. Using pole placement equations, we derive the controller that can be extended to the multi-step time delay case. The time-varying delays are estimated by a prediction error delay method using multiple predictors. Since the order of the estimation vector is not increased, the persistant exciting condition of control input is alleviated. Since the least square method gives biased parameter estimates for colored noise cases, the recursive instrumental variable method is used to estimate system parameters. The computational burden of the proposed method is less than the conventional adaptive methods. Computer simulations are performed to illustrate the efficiency of the proposed method.

• International Journal of Control, Automation, and Systems
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• 제4권1호
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• pp.53-62
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• 2006

In this paper, ATM network congestion control with explicit rate feedback is considered. In ATM networks, delays commonly appear in data transmission and have to be considered in congestion control design. In this paper, a bounded single round delay on the return path is considered. Our objective is to design an explicit rate feedback control that achieves a robust optimal $H_2$ performance regardless of the bounded time-varying delays. An optimization approach in terms of linear matrix inequalities (LMIs) is given. Saturation in source rate and queue buffer is also taken into consideration in the proposed design. Simulations for the cases of single source and multiple sources are presented to demonstrate the effectiveness of the design.

• 한국시뮬레이션학회논문지
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• 제8권4호
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• pp.1-8
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• 1999

This paper proposes an ATM switch architecture called Output Queued Batcher-Banyan switch (OQBBS). It consists of a Sorting Module, Expanding Module, and Output Queueing Modules. The principles of channel grouping and output queueing are used to increase the maximum throughput of an ATM switch. One distinctive feature of the OQBBS is that multiple cells can be simultaneously delivered to their desired output. The switch architecture is shown to be modular and easily expandable. The performance of the OQBBS in terms of throughput, cell delays, and cell loss rate under uniform random traffic condition is evaluated by computer simulation. The throughput and the average cell delay are close to the ideal performance behavior of a fully connected output queued crossbar switch. It is also shown that the OQBBS meets the cell loss probability requirement of $10^{-6}$.

• 한국항행학회논문지
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• 제16권1호
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• pp.62-69
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• 2012

다중제어 Toffoli(multiple-control Toffoli, MCT) 게이트는 원시 게이트에 의존적인 양자 기술을 필요로 하는 매크로 레벨 다치(multiple-valued) 게이트이며, Galois Field sum-of-product(GFSOP)형 양자논리 함수의 합성에 사용되어 왔다. 가역 논리는 저전력 회로 설계를 위한 양자계산(quantum computing, QC)에서 매우 중요하다. 본 논문은 먼저 GF4 가역 승산기를 제안한 후 GF4 승산기 기반의 quaternary MCT 게이트 실현을 제안하였다. MCT 게이트 실현을 위한 비교에서 제안한 MCT 게이트가 다중제어 입력이 증가할수록 종전의 작은 MCT 게이트 합성 방법보다 원시 게이트 수와 게이트 지연을 상당량 줄일 수 있음을 보였다.