• 대한전자공학회논문지
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• 제25권6호
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• pp.700-709
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• 1988

A new technique is proposed for switch-level logic simulation for NMOS and CMOS logic circuits. For the simple inverter the rise or fall delay time is approximated by a product of polynomials of the input waveform slope, the output loading capacitance and the device configuration ratio, the polynomial coefficients being so determined as to best fit the SPICE simuladtion results for a given fabrication process. This approach can easily and accurately be extened to the case of multiple input transitions. The simulation results show that proposed method can predict the delay times within 5% error and with a speed up by a factor of three orders of magnitude for several circuits tested, as compared with the SPICE simulation.

• 전자공학회논문지A
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• 제32A권12호
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• pp.209-219
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• 1995

As a new algorithm for RC tree delay estimation, we propose a $\tau$-model of the driver and a moment propagation method. The $\tau$-model represents the driver as a Thevenin equivalent circuit which has a one-time-constant voltage source and a linear resistor. The new driver model estimates the input voltage waveform applied to the RC more accurately than the k-factor model or the 2-piece waveform model. Compared with Elmore method, which is a lst-order approximation, the moment propagation method, which uses $\pi$-model loads to calculate the moments of the voltage waveform on each node of RC trees, gives more accurate results by performing higher-order approximations with the same simple tree walking algorithm. In addition, for the instability problem which is common to all the approximation methods using the moment matching technique, we propose a heuristic method which guarantees a stable and accureate 2nd order approximation. The proposed driver model and the moment propagation method give an accureacy close to SPICE results and more than 1000 times speedup over circuit level simulations for RC trees and FPGA interconnects in which the interconnect delay is dominant.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제5권2호
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• pp.114-118
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• 2005

Recently, in order to guarantee the quality of the final product from the production line, several equipments able to examine the polymer ingredients' quality are being used. Rheotruder is one of the equipments manufactured to measure the viscosity of the ingredient that is an important factor for the quality of final product. However, Rheotruder has nonlinear characteristics such as time delay which make systematic analysis difficult. In this paper, in order to enhance the performance of Rheotruder, a new scheme is introduced. It incorporates TDNN (Time Delay Neural Network) bank and Elman network to get a right decision on whether the tested ingredient is good or not. Furthermore, the proposed scheme is verified through real test execution.

• 반도체디스플레이기술학회지
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• 제10권2호
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• pp.49-56
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• 2011

In recent years, owing to the development of the image processing technology, the research to build control system using a vision sensor is stimulated. However, the time delay must be considered, because it works of time to get the result of an image processing in the system. It can be seen as an obstacle factor to real-time control. In this paper, using the pattern matching technique, the location of two objects is recognized from one image which was acquired by a camera. And it is implemented to a position control system as feedback data. Also, a possibility was shown to overcome a problem of time delay using PID controller. A number of experiments were done to show the validity of this study.

• Journal of Genetic Medicine
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• 제18권1호
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• pp.60-63
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• 2021

Gabriel-de Vries syndrome, caused by the mutation of YY1, is a newly defined genetic syndrome characterized by developmental delay, facial dysmorphism, and intrauterine growth retardation. A 7-month-old girl presented developmental delay and subtle facial dysmorphism including facial asymmetry, micrognathia, and low-set ears. Whole exome sequencing identified a de novo heterozygous missense variant in the YY1 (c.1220A>G; p.His407Arg) gene. Here, we examined the clinical and genetic characteristics of an infant with a novel likely pathogenic variant of YY1. This case expands the phenotypic spectrum of Gabriel-de Vries syndrome.

• 한국전산구조공학회논문집
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• 제32권6호
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• pp.401-408
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• 2019

본 연구는 헤테로코어 광파이버 센서를 활용하여 콘크리트 내부에서 발생되는 변형률의 측정을 통해 콘크리트의 프리스트레스를 직접 평가할 수 있는 새로운 매립형 센서모듈 개발을 최종 목표로 하고 있다. 이를 위하여 노출형 센서모듈을 이용한 성능발현 실험결과는 가력속도 0.12, 1.80mm/min일 때 52.1, 2.6sec로 최대 약 19배의 계측 지연현상이 발생하였다. 계측 지연현상은 구조물의 실시간 변화 상태를 계측하지 못하는 경우로 실시간 계측이 가능한 센서모듈의 개발을 위해서 추가실험이 필요한 것으로 판단하였다. 계측 지연현상 원인규명 실험은 3가지의 실험을 계획하였으며, 실험결과는 마찰저항에 의한 계측 지연이 지배적으로 확인되었다. 마찰이 제거된 장치를 이용한 센서모듈의 실험결과에서는 계측 지연현상이 나타나지 않은 것으로 확인되었다.

• 정보통신설비학회논문지
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• 제4권1호
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• pp.7-13
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• 2005

In this paper, we propose the time synchronization module on fiber optic repeater to use optic line delay for obtaining time synchronization between up-link and down-link, in the 2.3 GHz WiBro network using TDD/OFDM (Time Division Duplex/Orthogonal Frequency Division Multiplexing) Generally, when we use fiber optic repeater to remove the shade area, it occurs transmission delay which is caused by optic transmission between RAS (Radio Access Station) and fiber optic repeater and inner delay of fiber optic repeater. Because the WiBro system is adopting a TOO method and there exists the difference of switching time which is caused by these delay between up-link and down-link, it occurs ISI (Inter Symbol Interference), ICI (Inter Carrier Interference). These interference results in the reduction of the coverage. And the inconsistency between Up-Link and Down-Link switching time maybe gives rise to the interruption of communication. In order to prevent these cases, we propose synchronization module using analog optic line delay as the one of synchronizing up-link and down-link. And we propose the consideration factor for the designing time synchronization module and the feature of optic line of analog method. The measurement result of optic line time synchronization module of structure proposed is as follows, the delay error of $0.5{\mu}g$ and the insertion loss value below maximum 4.5dB in range of $0{\sim}40{\mu}s$. These results fully meet the specification of WiBro System.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 추계종합학술대회
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• pp.542-547
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• 2003

많은 해킹 기법의 발전과 해킹 툴 들이 대중화됨으로 인해 기존의 보안 기술만으로는 발전하는 해킹 기술에 대한 문제를 해결할 수 없게 되었다. 이러한 기존 보안 기술을 대체하기 위한 여러 기술이 등장하였는데 IDS가 그 대표적인 기술 중 하나이다. 네트워크 기반 침입 탐지 시스템인 N-IDS는 패킷에서 침입을 탐지하는 실시간 시스템이다. 따라서 패킷을 캡쳐하고 처리하는 능력이 시스템의 성능을 결정하게 되는데 기존의 N-IDS는 그 구조상 패킷의 캡쳐, 처리 후 다음 패킷 캡쳐까지의 시간 지연이 처리할 패킷의 종류에 따라 불규칙하게 발생한다. 기존의 단일 프로세서 구조를 가진 N-IDS로는 불규칙적인 시간 지연 문제를 해결할 수 없으므로 본 논문에서는 파일 소켓 및 멀티 쓰레드 구조를 이용하여 이러한 문제점을 해결하였다.

• 대한전기학회논문지:전력기술부문A
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• 제49권7호
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• pp.345-349
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• 2000

This paper presents an extended integral control with the PI controller by introducing the delay and decaying factors. The extended integral control scheme is developed by substituting the proportional convolution integral control for the PI(Proportional Integral) control. So far, the integral part of PI controller produces a signal that is proportional to the time integral of the input signal to the controller. The steady-state operation points are affected forever by errors in the past due to the input signal containing the information of the error in the past. These phenomena may cause some disturbances for other control purposes related to the given PI control. Introduction of forgetting factors to the error in the past can resolve the disturbance problems. Various forgetting factors are developed using the delay elements, the decaying factors, and the combination of the delay and decaying factors. The proposed various extended integral control schemes can be applicable to the corresponding PI control designs in which the error in the past may badly affect the current steady-state operation points and may cause some disturbances for other control purposes.

• 한국시뮬레이션학회논문지
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• 제12권3호
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• pp.55-68
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• 2003

As mobile IP has been suggested only to support mobility of mobile station(MS) by which it dose nothing but guarantee MS's new connection to the network, it is for nothing in Quality of Service(QoS) after handoff of MS. QoS is very important factor in mobile IP network to provide multimedia applications and real-time services in mobile environment, and it is closely related to handoff delay Therefore as a main issue in mobile IP research area, handoff delay problem is actively studied to guarantee and promote QoS. In this paper, in order to resolve such a problem, we suggest Simple Network Management Network(SNMP) information-based routing that adds keyword management method to information-based routing in active network, and then propose QoS controlled handoff by SNMP information-based routing. After setting up routing convergence time, modeling of suggested method and existing handoff method is followed in order to evaluate the simulations that are carried out with NS-2. The result of simulation show the improvement of handoff delay, and consequently it turns off the QoS has been improved considerably.