• 대한전기학회논문지:시스템및제어부문D
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• 제53권11호
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• pp.786-792
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• 2004

A wavelet based ECG data compression has become an attractive and efficient method in many mobile tele-cardiology applications. But large data size required for high compression performance leads a serious delay. In this paper, new wavelet compression method with minimum delay is proposed. It is based on deciding the type and compression ratio(CR) of block organically according to the standard deviation of input ECG data with minimum block size. Compression performances of the proposed algorithm for different MIT ECG Records were analyzed comparing other ECG compression algorithm. In addition to the processing delay measurement, compression efficiency and reconstruction sensitivity to error were also evaluated via random noise simulation models. The results show that the proposed algorithm has both lower PRD than other algorithm on same CR and minimum time in the data acquisition, processing and transmission.

• 전기전자학회논문지
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• 제20권4호
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• pp.378-384
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• 2016

본 논문은 통신 지연을 가지는 방향 네트워크로 연결된 고차 적분기시스템의 출력 피드백 일치문제를 다룬다. 이 문제를 해결하기 위하여 기존의 저이득 제어기에 설계변수를 추가한 새로운 동적 출력 피드백 제어기를 제안한다. 또한, 제안한 제어기의 존재성이 임의로 큰 통신지연이 존재하는 경우에도 항상 보장됨을 증명한다.

• 한국컴퓨터정보학회논문지
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• 제4권2호
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• pp.105-112
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• 1999

확산대역통신은 CDMA 시스템에서의 핵심기술이지만 SS통신에서의 문제점은 동기 방법이다. 동기방법에는 DLL(Delay Lock Loop), Tau-dither Loop, SO(Synchronous Osillator) 등이 있다. 그러나 아날로그 동작시에는 회로의 크기가 커지고 조정이 어려운 문제가 있어 본논문에서는 Digital Delay Lock Loop (DDLL)을 제안하고 실험을 통해 그 성능을 평가하였다.

• 전기전자학회논문지
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• 제18권4호
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• pp.517-522
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• 2014

본 논문은 임의의 네트워크 시간 지연이 존재하는 선형 다개체 시스템의 일치문제를 다룬다. 다개체 시스템의 상태일치를 위한 충분조건은 선형행렬방정식을 이용하여 제공된다. 또한, 제안한 충분조건아래에서 임의의 크기를 갖는 네트워크 지연이 존재하는 경우에도 일치에 도달할 수 있음을 증명한다. 마지막으로 제안한 결과의 유효성을 증명하기 위하여 수치 예제를 제공한다.

• 전기전자학회논문지
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• 제17권1호
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• pp.83-88
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• 2013

본 논문에서는 입력과 출력에 동시에 시간 지연이 존재하는 피드포워드 비선형시스템에 대한 출력 피드백 제어 방법을 제안한다. 제안한 출력 피드백 제어기는 선형관측기와 선형제어기로 구성된다. Lyapunov-Krasovskii 정리를 이용하여 임의의 크기를 갖는 시간지연에 대하여 전역적 점근 안정도를 보장함을 증명한다. 마지막으로 제안한 결과의 유효성을 증명하기 위하여 모의실험 예제를 제공한다.

• 대한임베디드공학회논문지
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• 제16권3호
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• pp.113-117
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• 2021

The data gathering delay and the network lifetime are important indicators to measure the service quality of wireless sensor and actuator networks (WSANs). This study proposes a dynamically cluster head (CH) selection strategy and automatic scheduling scheme of collectors for prolonging the network lifetime and shorting data gathering delay in WSAN. First the monitoring region is equally divided into several subregions and each subregion dynamically selects a sensor node as CH. These can balance the energy consumption of sensor node thereby prolonging the network lifetime. Then a task allocation method based on genetic algorithm is proposed to uniformly assign tasks to actuators. Finally the trajectory of each actuator is optimized by ant colony optimization algorithm. Simulations are conducted to evaluate the effectiveness of the proposed method and the results show that the method performs better to extend network lifetime while also reducing data delay.

• 한국BIM학회 논문집
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• 제12권4호
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• pp.32-40
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• 2022

The block-unit housing renewal project was presented as an alternative method to overcome the side effects of large-scale renewal projects while improving poor residential conditions. However, projects implementation is prolonged and even the pace of projects, which was considered an various incentives, is being delayed for the most part. In this study, delay factors are drawn by eight; conflict among association members, contract delay of joint implementation, participation paucity of constructor, inadequate project guidelines, alteration of project plan, lack of renewal project professionals, stricter loan restriction of HUG, lack of capacity of project operator. We categorized those eight factors to three aspects such as implementation, participants and proposition and suggested improvement alternatives according to three aspects.

• 대한전자공학회논문지
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• 제24권1호
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• pp.52-59
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• 1987

A new on-line estimation algorithm for a time varying time delay is proposed. This algorithm is based on the concept of minimization of prediction error. As only the parameters directly related to the poles and zeros of the process are estimated in the algorithm, persistently exciting condition for the convergence of parameters can be less restrictive. Under some assumptions which is necessary in adaptive control, it is shown that this algorithm estimates time varying time delay accurately. In view of computational burden, this algorithm needs far less amount of calculations than other methods. The larger the time delay is, the more effective this algorithm is . Computer simulation shows good properties of the algorithm. This algorithm can be used effectively in adaptive control of large dead time processes.

• ETRI Journal
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• 제39권4호
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• pp.582-591
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• 2017

To address the wire complexity problem in large-scale globally asynchronous, locally synchronous systems, a current-mode ternary encoding scheme was devised for a two-phase asynchronous protocol. However, for data transmission through a very long wire, few studies have been conducted on reducing the long propagation delay in current-mode circuits. Hence, this paper proposes a current steering logic (CSL) that is able to minimize the long delay for the devised current-mode ternary encoding scheme. The CSL creates pulse signals that charge or discharge the output signal in advance for a short period of time, and as a result, helps prevent a slack in the current signals. The encoder and decoder circuits employing the CSL are implemented using $0.25-{\mu}m$ CMOS technology. The results of an HSPICE simulation show that the normal and optimal mode operations of the CSL achieve a delay reduction of 11.8% and 28.1%, respectively, when compared to the original scheme for a 10-mm wire. They also reduce the power-delay product by 9.6% and 22.5%, respectively, at a data rate of 100 Mb/s for the same wire length.

• 화약ㆍ발파
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• 제18권1호
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• pp.53-58
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• 2000

Thermal analysis, analysis of combustion residue and combustion characteristics measure ment such as burning rate or temperature were carried out to clarify the combustion mechanism of a tungsten- potassium perchlorate-barium chromate chromate delay powder. The results obtained are as follows. The main reaction of the delay powder of tungsten-potassium perchlorate-barium chromate is the oxidation of tungsten by potassium perchlorate. Barium chromate acts as a burning rate modifier, and the smaller the larger is the burning rate. Three types of delay composition used in this study show characteristic burning behavior. A stoichiomertric or a oxidizer-rich composition has a small linear burning rate. although it is has a large heat of combustion. On the other hand, a tungsten-excess or a fuel-rich composition with a small heat of combustion has a larger linear burning rate than the former, showing a small fractional oxidation of tungeten (below 10%) contained in the delay powder. From these results, a surface combustion mechanism is proposed for the combustion mechanism of this delay powder.