• 제목/요약/키워드: spectral theory

검색결과 248건 처리시간 0.022초

마이크로파 거리계의 VCO 비선형성에 의한 시스템 특성 분석 및 개선 방안 연구 (Improved Design of the Microwave Level Meter upon VCO Nonlinearity)

  • 전중창;김정목임종수
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 추계종합학술대회 논문집
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    • pp.331-334
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    • 1998
  • In this paper, we have presented an improved design of the microwave level meter based on the principle of FM-CW radar. First, we have analyzed the effect of VCO nonlinearity on the spectral broadening of the beat signal, and presented a new type of design theory to linearize VCO tuning curve adopting FFT algorithm. Simulation results for a VCO having the linearity of 25% have been presented, which show the usefulness of the design algorithm.

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SPECTRAL THEOREMS ASSOCIATED TO THE DUNKL OPERATORS

  • Mejjaoli, Hatem
    • Korean Journal of Mathematics
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    • 제24권4호
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    • pp.693-722
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    • 2016
  • In this paper, we characterize the support for the Dunkl transform on the generalized Lebesgue spaces via the Dunkl resolvent function. The behavior of the sequence of $L^p_k$-norms of iterated Dunkl potentials is studied depending on the support of their Dunkl transform. We systematically develop real Paley-Wiener theory for the Dunkl transform on ${\mathbb{R}}^d$ for distributions, in an elementary treatment based on the inversion theorem. Next, we improve the Roe's theorem associated to the Dunkl operators.

Spectral analysis of random process

  • Akizuki, Kageo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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    • pp.13-20
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    • 1994
  • The spectrum estimation methods of random processes are expressed in this paper. Beginning with the basic theory, non-parametric and parametric methods are overviewed. As to non-parametric method, numerical calculation method is also discussed. As to parametric method, AR model is a very famous and effective model representing random process. Estimation methods of AR parameters which have been proposed are mentioned here. Wavelet analysis is a recently interested technique in signal processing. An application of wavelet analysis is also shown.

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자화된 페라이트 기판상의 다중 결합 마이크로스트립 선로 해석 (Analysis of multiple coupled microstrip lines on a magnetized ferrite substrate)

  • 문영찬;윤상원;창익수
    • 전자공학회논문지A
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    • 제33A권5호
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    • pp.65-74
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    • 1996
  • in this paper, the propagation characteristics of the dominant modes in multiple coupled microstrip lines on a magnetized ferrite substrate are analyzed. The propagation constants and characteristic impedances are calculated by using the spectral domain method. With the numerical results, multi-port impedance parameters as well as scattering parameters are derived from nonreciprocal transmission line equations which are consistent with conventional transmission line theory. In additon, the numerical resutls of nonreciprocal characteristics for various values of structural, material parameters, and external magnetic fields are also presented.

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피치 알고리즘 수정 및 소음에의 적용 (Modification of Pitch Algorithm and Its Application to Noise)

  • Shin, Sung-Hwan;Ih, Jeong-Guon
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 추계학술대회논문초록집
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    • pp.354.1-354
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    • 2002
  • Pitch is a perception related to frequency, one of the psychological aspects or attributes of tones, and an important factor to determine sound quality of sound together with loudness and timber. while a study on pitch has been actively achieved In the part of speech recognition and speech separation, that for analysis and improvement of product sound quality is not yet enough. (omitted)

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LCD 패널 상의 불량 검출을 위한 스펙트럴 그래프 이론에 기반한 특성 추출 방법 (Feature extraction method using graph Laplacian for LCD panel defect classification)

  • 김규동;유석인
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2012년도 한국컴퓨터종합학술대회논문집 Vol.39 No.1(B)
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    • pp.522-524
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    • 2012
  • For exact classification of the defect, good feature selection and classifier is necessary. In this paper, various features such as brightness features, shape features and statistical features are stated and Bayes classifier using Gaussian mixture model is used as classifier. Also feature extraction method based on spectral graph theory is presented. Experimental result shows that feature extraction method using graph Laplacian result in better performance than the result using PCA.

러프 집합을 이용한 다중 분광 이미지 데이터의 분류 (Classification of Multi Spectral Image Data using Rough Sets)

  • 원성현;이병성;정환묵
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1997년도 춘계학술대회 학술발표 논문집
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    • pp.205-208
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    • 1997
  • Traditionally, classification of remote sensed image data is one of the important works for image data analysis procedure. So, many researchers devote their endeavor to increasing accuracy of analysis, also, many classification algorithms have been proposed. In this paper, we propose new classification method for remote sensed image data that use rough set theory. Using indiscernibility relation of rough sets, we show that can classify image data very easily.

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생체 카오스의 비선형 시계열 데이터 분석 (Nonlinear Time Series Analysis of Biological Chaos)

  • 이병채;이명호
    • 대한의용생체공학회:의공학회지
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    • 제15권3호
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    • pp.347-354
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    • 1994
  • This paper describes a diagnostic protocol of nonlinear dynamic characteristics of biological system using chaos theory. An integrated chaos analysis system for the diagnosis of biological system was designed. We suggest a procedure of attractor reconstruction for reliable qualitative and quantitative analysis. The effect of autonomic nervous system activity on heart rate variability with power spectral analysis and its characteristics of chaotic attractors are investigated. The results show the applicability to evaluate the mental and physical conditions using nonlinear characteristics of biological signal.

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分子 Exciton 狀態에서의 Stark 效果 (Stark Effect in Molecular Exciton States)

  • 이조웅
    • 대한화학회지
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    • 제19권5호
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    • pp.304-316
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    • 1975
  • 제이양자화 형식을 이용하여 분자 exciton 상태에서의 Stark 효과를 설명하는 이론을 전개하였다. 하나의 단위 세포당 두 개이상의 분자를 함유하는 결정에서의 스펙트럼 분리는 Stark효과 뿐만 아니라 Davydov 효과에도 관계 있으므로 이 두 효과를 모두 고려하여 결과에 반영되도록 하였다. 특히 단위세포당 두개의 분자를 함유하는 결정에 있어서의 스펙트럼 분리는 외부에서 걸어준 균일한 전기장의 세기에 따라 쌍곡선함수적으로 변한다는 것을 보였으며 이로부터 한 분자의 들뜬 상태에서의 쌍극자모멘트에 관한 정보를 얻을 수 있음을 밝혔다.

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Earthquake response spectra estimation of bilinear hysteretic systems using random-vibration theory method

  • Yazdani, Azad;Salimi, Mohammad-Rashid
    • Earthquakes and Structures
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    • 제8권5호
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    • pp.1055-1067
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    • 2015
  • A theoretical procedure to estimate spectral displacement of a hysteretic oscillator with bilinear stiffness excited by band-limited excitation is presented. The stochastic method of ground-motion simulation is combined with the random vibration theory to compute linear and nonlinear structural response. The response is obtained by computing the root-mean-square oscillator response using dissipation energy balancing by integrating over all energy levels of system weighting with the stationary probability density of the energy. The results are presented in a convenient form, and the accuracy of the procedure is assessed by comparison with results obtained with the time-domain method using the recorded data. The model shows little or no bias at the structural period of engineering interest.