• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.235-238
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• 2006

This paper is about the code that realizes the $e^N$-Method for boundary-layer transition prediction. The $e^N$-Method based on the linear stability theory is applied to predicting boundary-layer transition frequently. This paper deals with the construction of code, stability analysis and the calculation of N-factor. The results of transition prediction using the $e^N$-Method for flat plate/cone compressible boundary-layers are presented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 G
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• pp.2299-2301
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• 1998

In this paper, a modified RBF (Radial Basis Function) neural network structure is suggested for the prediction of time series with non-linear, non-stationary characteristics. Conventional RBF neural network predicting time series by using past outputs is for sensing the trajectory of the time series and for reacting when there exists strong relation between input and hidden neuron's RBF center. But this response is highly sensitive to level and trend of time serieses. In order to overcome such dependencies, hidden neurons are modified to react to the increments of input variable and multiplied by increments(or decrements) of out puts for prediction. When the suggested structure is applied to prediction of Lorenz equation, and Rossler equation, improved performances are obtainable.

• 한국음향학회지
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• 제28권7호
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• pp.618-629
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• 2009

The MPEG-4 Audio Lossless Coding (ALS) standard belongs to the family MPEG-4 audio coding standards. In contrast to lossy codecs such as AAC, which merely strive to preserve the subjective audio quality, lossless coding preserves every single bit of the original audio data. The ALS core codec is based on forward-adaptive linear prediction, which combines remarkable compression with low complexity. Additional features include long-term prediction, multichannel coding, and compression of floating-point audio material. This paper describes the basic elements of the ALS codec with a focus on prediction, entropy coding, and related tools and points out the most important applications of this standardized lossless audio format.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -1
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• pp.102-105
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• 2002

A noise reduction technique to reduce background noise in corrupted voice is proposed. The proposed method is based on linear prediction and takes advantages of periodicity of voiced speech. A voiced sound is regarded as a periodic stationary signal in short time interval. Therefore, the current voice signal is correlated with the voice signal delayed by a pitch period. A linear predictor can estimate only the current signal correlated with the delayed signal. Therefore, the enhanced voice can be obtained as output of the linear predictor. Simulation results show that the proposed method is able to reduce the background noise.

• Journal of applied mathematics & informatics
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• 제28권1_2호
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• pp.351-361
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• 2010

The solution of large sparse linear systems is one of the most important problems in large scale scientific computing. Among the many methods developed, the preconditioned Krylov subspace methods are considered the preferred methods. Selecting a suitable preconditioner with appropriate parameters for a specific sparse linear system presents a challenging task for many application scientists and engineers who have little knowledge of preconditioned iterative methods. The prediction of ILU type preconditioners was considered in [27] where support vector machine(SVM), as a data mining technique, is used to classify large sparse linear systems and predict best preconditioners. In this paper, we apply the data mining approach to the sparse approximate inverse(SAI) type preconditioners to find some parameters with which the preconditioned Krylov subspace method on the linear systems shows best performance.

• 한국정보통신학회논문지
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• 제1권1호
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• pp.77-83
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• 1997

본 논문에서는 현재 디지털 이동통신 시스템에서 운용되고 있는 QCELP(Qualcomm Code Excited Linear Predictor) 음성부호화 방식과 향후 IMT-2000 (International Mobile Telecommunications 2000) 등의 시스템에서 사용 예정인 CS-ACELP(Conjugate Structure Algebraic Code Excited Linear Prediction) 음성부호화 방식과의 성능을 비교한다. 특히 무선 채널을 사용하는 이동통신환경의 특징인 채널에러로 인한 음성부호화기의 성능을 비교함으로써 채널에러에 강인한 음성부호화 알고리즘 설계에 대한 고찰을 유도한다.

• 대한전자공학회논문지
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• 제19권1호
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• pp.1-8
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• 1982

적응선형자측(adaptive linear prediction) 방법에 의한 음성신묵의 parametric representation에 대한 연구는 이제까지 널리 행해져 왔다. 본 논문에서는 LPC(Linear Predictive Coding) 방법으로 한글 격모음및 일체 복함모음에 대한 parameter들을 각각 분석해 내어서 이를 이용하여 한글모음 상호간의 근사도(affinity)에 대한 통계적 연구를 하여 음성학적인 면과 비교 고찰하였다. 그리고 그에 따른 결과로서 음성학적으로 근사하여 혼동되는 경향이 있는 모음간에는 vocal tract의 dynamic parameter 간에도 근사성이 있음을 밝혔다.

• 대한전자공학회논문지
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• 제15권5호
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• pp.1-6
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• 1978

본 논문은 음성신호의 디지탈화와 대역식 축소에 관한 일부1)에 이은 이부 논문이다. 몇가지 근래에 개발된 Vocoding 방법, 즉 linear predictive coding (LPC), formant vocoding, residual excited linear prediction (RELP) vocoding,그리고 adaptive predictive coding(APC)에 관하여 논하였다. 본 논문에서는 음성전송에 있어서의 대역 제한 방법 중 지금 가장 효과가 있는 LPC방법을 중점적으로 취급하였다. 또한 현재 처하고 있는 문제점들과 해결책을 토의하였다.

• 대한전자공학회논문지
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• 제18권4호
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• pp.27-33
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• 1981

한국어의 주요 단모음에 대하여 음정을 변화시켜 가면서 전형 예측법에 따른 모형 스펙트럼과 성도의 형태를 추정함으로써 음의 고저에 따른 특성 변화를 분석하였다. 또 분석한 결과를 이용하여 음소의 조합에 의한 음성합성방안을 제시하고 실험에 의해 그 타당성을 입증하였다.

• 물과 미래
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• 제8권2호
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• pp.93-99
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• 1975

A linear and optimum linear systems have been reviewed in some detail. The procedure of the solution of the Wiener-Hopf equation analytically in time domain is given and the prediction of downstream outflow for given upstream inflow are made. The predicted results are fairly satisfaotory. The intended physical interpretation of the analytical solution could be descriptable but it was found that the evaluation of the parameters of the response function is rather difficult due to complicacy and a great deal of works.