• 한국정보전자통신기술학회논문지
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• 제3권1호
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• pp.13-18
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• 2010

본 연구에서는 ECG를 통하여 심박수를 R-R 간격을 이용한 방법으로 자동 추출하는 방법에 관하여 연구하였다. 육안으로 측정한 심박수를 기준으로, 2차 미분을 이용하여 심박수를 추출하는 방법, 자기상관함수를 이용하여 심박수를 추출하는 방법을 비교하여 고찰하였다. 실험 데이터는 MIT/BIH database를 이용하였다. 이를 바탕으로 직접 ECG 측정기를 제작하여 심박수를 자동 측정하여 보고 기존의 환자감시장치(ICU)와 비교하여 보았다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.489-492
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• 2007

The P-wave velocity at the formation which contains gas hydrate varies very wide upon gas hydrate existence. These features on seismic shot gather can not be simulated normally by numerical modeling of homogeneous medium so that we need that of random inhomogeneous medium instead. We, in this study generated random inhomogeneous medium using gaussian ACF, exponential ACF and von Karman ACF and that we supposed the random inhomogeneous medium be gas hydrate formation to execute numeric modeling. The modeling result shows the typical effect by scattering caused by random hydrate formation as is observed from seismic shot gather where hydrate exist.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1994년도 춘계학술대회
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• pp.96-99
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• 1994

Despite the simplicity of processing, a conventional autocorrelation function(ACF) method for the precise determination of fetal heart rate (FHR) has many problems. In case of weak or noise corrupted Doppler ultrasound signal. the ACF method is very sensitive to the threshold level and data window length. It is very troublesome to extract FHR when there is a data loss. To overcome these problems, the high resolution pitch detection algorithm was adopted to estimate the FHR. This method is more accurate, robust and reliable than the ACF method. With a lot of calculation, however, it is impossible to process real time FHR estimation. This paper is presented a new FHR estimation algorithm for real time processing.

• 한국콘텐츠학회논문지
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• 제4권4호
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• pp.205-213
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• 2004

본 논문에서는 크기 불변 패턴인식을 위하여 광 웨이브렛 PO-fSDF(WPOfSDF) 필터 및 개선된 필터 합성알고리듬을 제안하였다. 제안한 필터는 크기가 변화된 영상을 학습영상으로 사용하여 PO-fSDF로 합성한 후 입력을 위한 웨이브렛 함수를 필터에 곱하여 합성한다. 컴퓨터 모의실험을 통하여 제안된 필터가 크기불변 인식을 할 수 있고, 잡음을 가지는 입력영상의 경우 SNR이 개선되며 필터합성시 반복횟수도 줄어듦을 확인할 수 있었다. 그리고 광실험시 발생하는 광축정렬 문제는 전체 시스템을 FSJTC로 구성함으로써 해결하였다.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1990년도 추계학술대회
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• pp.99-102
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• 1990

Cross correlation method was newly applied for the calculation of latency of evoked otoacoustic emission. The latency was calculated from the main peak of cross correlation function, which is one of possible definition of latency. The output was also compared with those of conventional autocorrelation method. The results show that cross correlation method has better performance than that of conventional method.

• 한국통신학회논문지
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• 제19권2호
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• pp.373-380
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• 1994

본 논문에서는 음성신호를 일정한 크기로 적응시켜 최적의 특징을 추출할 수 있는 방법을 제안하였다. 음성신호의 특징을 추출하기 위하여 고속선형예측 알고리즘인 FRLS 적용할 때 음성신호를 일정한 크기로 분할한 후 각 프레임 마다 제안한 균등사기상관함수를 가지고 최적특징을 추출하였다.

• 한국시뮬레이션학회논문지
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• 제5권1호
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• pp.1-12
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• 1996

We propose a new approach to classifying a time series data into one of the autoregressive moving-average (ARMA) models. It is bases on two pattern recognition concepts for solving time series identification. The one is an extended sample autocorrelation function (ESACF). The other is a neural network-driven decision tree classifier(NNDTC) in which two pattern recognition techniques are tightly coupled : neural network and decision tree classfier. NNDTc consists of a set of nodes at which neural network-driven decision making is made whether the connecting subtrees should be pruned or not. Therefore, time series identification problem can be stated as solving a set of local decisions at nodes. The decision values of the nodes are provided by neural network functions attached to the corresponding nodes. Experimental results with a set of test data and real time series data show that the proposed approach can efficiently identify the time seires patterns with high precision compared to the previous approaches.

• 상하수도학회지
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• 제26권3호
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• pp.479-486
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• 2012

Runoff characteristics of pollutant loads of the lower Han River was studied before full implementation of Total Pollution Load Management System(TPLMS). Magnitude of macroscopic(annual) fluctuation was in the order of Namhan River > Han River > Bukhan River, gross weight TP > gross weight TN > gross weight BOD, gross weight deviation > concentration deviation. Flux variation was higher than that of concentration. Microscopic(weekly) fluctuation showed similar pattern to macroscopic scale. TP showed the highest deviation resulting in the lowest reliability. 60% of annual flux passed during summer 3months resulting in 43-46% pass of gross weight at the lower Han River. Strong correlation was found between flux and gross weight especially in gross weight TN. Gross weight pollution increased as high as 400% while passing Seoul area due to the concentration. The deviation from moving average increased during summer season in the gross weight TP and BOD. Seasonal tendency was confirmed especially in gross weight TN and TP using autocorrelation function.

• 전자공학회논문지B
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• 제32B권5호
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• pp.788-797
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• 1995

In this paper, a variable time-scale modification using SOLA(Synchronized OverLap and Add) is proposed, which takes into consideration the different time-scaled characteristics of voiced and unvoiced speech, Generally, voiced speech is subject to higher variations in length during time-scale modification than unvoiced speech, but the conventional method performs time-scale modification at a uniform rate for all speech. For this purpose, voiced and unvoiced speech duration at various talking speeds were statistically analyzed. The sentences were then spoken at rates of 0.7, 1.3, 1.5 and 1.8 times normal speed. A clipping autocorrelation function was applied to each analysis frame to determine voiced and unvoiced speech to obtain respective variation rates. The results were used to perform variable time-scale modification to produce sentences at rates of 0.7, 1.3, 1.5, 1.8 times normal speed. To evaluate performance, a MOS test was conducted to compare the proposed voiced/unvoiced variable time-scale modification and the uniform SOLA method. Results indicate that the proposed method produces sentence quality superior to that of the conventional method.

• 대한기계학회논문집B
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• 제21권12호
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• pp.1679-1689
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• 1997

In this paper, a precise description is given to the basic theory as well as the detailed algorithms for the numerical treatment of the method of POD (proper orthogonal decomposition). This method is then applied to analysing the numerical solutions of one-dimensional shallow-water equations to show how the method is affected by various parameters such as the sampling time, sampling numbers, and the spatial resolution for the autocorrelation function. A few curious features associated with this flow model found through the analysis are further explained and discussed.