• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.11
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• pp.41-48
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• 2005

The crosstalk effects that can be observed in the very dee submicron semiconductor chips are due to the coupling capacitances between interconnect lines. The accuracy of the full-chip timing analysis is determined by the accuracy of the estimated propagation delays of cells and interconnects within the chip. This paper presents a CMOS cell driver model and delay calculation algerian capturing the crosstalk effects due to the coupling capacitances. The proposed model and algorithm were implemented in a delay calculation program and used to estimate the propagation delays of the benchmark circuits extracted from a chip layout. We observed that the average discrepancy from HSPICE simulation results is within $1\%$ for the circuits with a victim affected by $0\~10$ aggressors.

• Convergence Security Journal
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• v.6 no.1
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• pp.55-63
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• 2006

In this paper, an algorithm that provisions absolute differentiation of packet delays is proposed with an objective for enhancing quality of service (QoS) in future packet networks. It features an adaptive scheme that compensates the deviation for prediction on the traffic to be arrived continuously. It predicts the traffic to be arrived at the beginning of a time slot and measures the actual arrived traffic at the end of the time slot, and derives the deviation between the two quantity. The deviation is utilized to the delay control operation for the next time slot to offset it. As it compensates the prediction error continuously, it shows superior adaptability to the bursty traffic as well as the constant rate traffic. It is demonstrated through simulation that the algorithm meets the quantitative delay bounds and shows superiority to the traffic fluctuation in comparison with the conventional mechanism.

• Journal of the Korean Institute of Intelligent Systems
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• v.12 no.2
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• pp.144-150
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• 2002

In this paper a design of neuro-fuzzy-based predictive controller for nonlinear systems with time-delay is proposed. The proposed control system contains two neuro-fuzzy systems called ANFIS(Adaptive Neuro-Fuzzy Inference System). One is run as a series-parallel mode and the other is run as a parallel mode. An ANFIS running in series-parallel mode emulates the response of the nonlinear system with time-delay. Another ANFIS running in parallel mode generates the predicted output of the nonlinear system to compensate for the time-delays. Therefore, the proposed control system can be thought of as an extension of Smith-predictor scheme to the nonlinear systems with time-delay. A detailed design Procedure is presented and finally computer simulations are executed for the effectiveness of the proposed control scheme.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.7-13
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• 2018

The strength of concrete is affected significantly not only by the internal influence factors of cement, water, sand, aggregate, and admixture, but also by the external influence factors of concrete placement delay and curing temperature. The objective of this research was to predict the concrete strength considering both the internal and external influence factors when concrete is placed at the construction site. In this study, a concrete strength test was conducted on the 24 combinations of internal and external influence factors, and a neural network model was constructed using the test data. This neural network model can predict the concrete strength considering the external influence factors of the concrete placement delay and curing temperature when concrete is placed at the construction site. Contractors can use the concrete strength prediction neural network model to make concrete more robust to external influence factors during concrete placement at a construction site.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10c
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• pp.445-447
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• 2003

최근 무선네트워크의 급속한 확대로 무선인터넷 접속 또한 크게 증가하고 있다. 무선인터넷을 이용하는 Voice over IP 서비스는 IP 기반의 인터넷과 셀룰러 네트워크를 합쳐 놓은 것과 유사하며 모바일 노드의 이동성 확보가 핵심 기술이다. 특히 VoIP 서비스 이용자는 지연이나 끊어짐에 대하여 매우 민감하므로 가급적 지연시간이 적은 핸드오프 기법이 필요하다. 본 연구에서는 무선네트워크를 이용하는 VoIP 서비스 프로토콜 중 하나인 SIP를 기반으로 이동성 관리를 위한 신호의 흐름을 도시하여 발생 가능한 지연의 구성요소를 분석하였으며 핸드오프 지연을 줄이기 위한 Prediction Shadow Registration을 제안하였다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.07a
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• pp.99-101
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• 2011

본 논문에서는 WiMAX 의 신호세기(CINR: Carrier to Interference + Noise Ratio)의 변화와 예측 방법에 대해 연구한다. WiMAX 와 같은 무선 네트워크에서는 신호세기가 불규칙하게 변화하기 때문에 비디오 스트리밍시 에러나 지연이 발생할 수 있다. CINR 은 클라이언트 측의 가용 대역폭을 결정하는 중요한 요소이다. 하지만 기존의 RTCP(Real-time Transport Control Protocol)를 이용한 비트율 제어는 RTT(Round Trip time), PLR(Packet Loss Rate) 등의 정보를 사용하기 때문에 부정확하거나 지연이 발생될 수 있다. 이를 보완하기 위한 CINR 을 직접 비트율 제어에 사용하는 방법에 대해 연구하기에 앞서, 본 논문에서는 CINR 을 분석하고 미래의 값을 예측하는 방법에 대해 연구한다. 본 논문의 분석을 통해 CINR 의 예측을 비교적 정확하게 수행할 수 있다면 앞으로의 가용 대역폭을 비교적 정확하게 예측할 수 있고 효율적인 비디오 스트리밍 시스템을 제안할 수 있다.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.155-159
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• 2007

S/W 개발 프로젝트의 품질, 비용, 개발 기간을 잘 관리하여 프로젝트를 성공시키기 위해 PM 은 프로젝트의 종료시점과 예산의 초과를 예측할 수 있어야 한다. PMBOK 의 비용관리의 Earned Value Method 는 프로젝트의 진행에 따른 생산성의 변화와 그에 따른 비용과 일정의 증가 추정에 대한 규칙을 제시한다. 그러나 EVM 은 제조공정에서는 그 효과를 증명하였지만, S/W 프로젝트에서는 적용이 힘들어 잘 활용되고 있지 않다. 이는 사람이 주요 자원인 S/W 프로젝트에서는 Actual Cost 의 측정이 쉽지 않기 때문이다. 따라서 본 논문에서는 S/W 프로젝트 관리에서 Earned Value 의 측정이 쉽지 않아 추정되기 힘든 지연된 종료 시점에 대한 예측을 PMBOK 과 CMMI 에서 제시하는 관리 영역과의 연관성을 활용하고, EVM 을 보완하여 지연에 대한 예측모델을 만들어보고자 한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.10a
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• pp.1299-1301
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• 2015

항공서비스에 있어서 여러 중요한 요소가 있지만 그 가운데 가장 중요한 요소로 운항의 정시성을 들 수 있다. 본 논문에서는 마코프 체인을 이용하여 항공사 및 공항의 정시성을 평가하고 예측하고자 하였다. 실험용 데이터로 선택한 미국 항공운항 데이터를 기상 악화에 따른 도착지연시간을 기준으로 정시성이 우수한 항공사를 제안하는 기능을 테스트하였다. 본 논문에서는 과거의 항공운항 데이터를 활용하여 미래의 운항 지연을 예측할 수 있도록 마코프 체인을 기반으로 한 예측 방법을 제시하였다.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.39 no.4
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• pp.38-49
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• 2002

In this paper, we propose a solution for random time-delay in teleoperation via internet using QoS, and show the experimental results of our proposed method. By ensuring a constant bandwidth required for the specific telecontrolled system, we change irregular random time-delay to a predictable time-delay, and so we can control the system with the time-delay shorter than the specified time-delay. Through the experimental results, we show the effectiveness of our proposed method.

• Phonetics and Speech Sciences
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• v.12 no.1
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• pp.51-63
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• 2020

Phonological awareness is a metalinguistic awareness ability of phonology and is known to predict language skills, such as reading and vocabulary skills. The purpose of this study was to investigate the relationship between phonological awareness, phonological processing, and language skills in 4- to 6-years-old typically developing (TD) children and children with language delay (LD). A total of 32 children (TD=18, LD=15) participated in this study. They performed a phonological awareness task consisting of counting, deletion, and discrimination at syllable level. Nonword Repetition, Digit Backward, Receptive & Expressive Vocabulary Test, and Grammaticality Judgment Task were performed to analyze the correlation between phonological awareness, phonological processing, and language ability. A multiple stepwise regression analysis was performed to examine the phonological awareness subtasks that predict language ability. In the TD group, the syllable categorization task significantly predicted the receptive vocabulary and the performance of the Grammaticality Judgment Task. The LD group showed that the syllable counting task significantly predicted the receptive vocabulary, the expressive vocabulary, and the performance of the Grammaticality Judgment Task. The results showed that the phonological awareness performance was significantly different between the two groups. Further, correlation analysis and regression analysis showed different results for each group. The result of the phonological awareness performance predicted the language ability of each group significantly, suggesting the importance of the meta-linguistic awareness ability of phonology.