• 제목/요약/키워드: Gaussian function

검색결과 925건 처리시간 0.028초

OPTIMAL APPROXIMATION BY ONE GAUSSIAN FUNCTION TO PROBABILITY DENSITY FUNCTIONS

  • Gwang Il Kim;Seung Yeon Cho;Doobae Jun
    • East Asian mathematical journal
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    • 제39권5호
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    • pp.537-547
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    • 2023
  • In this paper, we introduce the optimal approximation by a Gaussian function for a probability density function. We show that the approximation can be obtained by solving a non-linear system of parameters of Gaussian function. Then, to understand the non-normality of the empirical distributions observed in financial markets, we consider the nearly Gaussian function that consists of an optimally approximated Gaussian function and a small periodically oscillating density function. We show that, depending on the parameters of the oscillation, the nearly Gaussian functions can have fairly thick heavy tails.

Approximation for the Two-Dimensional Gaussian Q-Function and Its Applications

  • Park, Jin-Ah;Park, Seung-Keun
    • ETRI Journal
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    • 제32권1호
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    • pp.145-147
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    • 2010
  • In this letter, we present a new approximation for the twodimensional (2-D) Gaussian Q-function. The result is represented by only the one-dimensional (1-D) Gaussian Q-function. Unlike the previous 1-D Gaussian-type approximation, the presented approximation can be applied to compute the 2-D Gaussian Q-function with large correlations.

A Generic Craig Form for the Two-Dimensional Gaussian Q-Function

  • Park, Seung-Keun;Choi, U-Jin
    • ETRI Journal
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    • 제29권4호
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    • pp.516-517
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    • 2007
  • In this letter we present a generic Craig form for the two-dimensional (2-D) Gaussian Q-function. The presented Craig form provides an alternative solution to the problems of computing probabilities involving a form of the 2-D Gaussian Q-function.

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코사인 모듈화 된 가우스 활성화 함수를 사용한 캐스케이드 코릴레이션 학습 알고리즘의 성능 향상 (An Improvement of Performance for Cascade Correlation Learning Algorithm using a Cosine Modulated Gaussian Activation Function)

  • 이상화;송해상
    • 한국컴퓨터정보학회논문지
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    • 제11권3호
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    • pp.107-115
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    • 2006
  • 본 논문에서는 캐스케이드 코릴레이션 학습 알고리즘을 위한 새로운 클래스의 활성화 함수를 소개한다. 이 함수는 코사인으로 모듈화된 가우스 함수로서 편의상 이 활성화 함수를 코스가우스(CosGauss) 함수라고 칭하기로 한다. 이 함수는 기존의 시그모이드 함수(sigmoidal function), 하이퍼볼릭탄젠트 함수(hyperbolic tangent function), 가우스 함수(gaussian function)에 비해서 등성이(ridge)를 더 많이 얻을 수 있다. 이러한 등성이들로 인하여 빠른 속도로 수렴하고 패턴인식 속도를 향상 시켜서 학습 능력을 향상시킬 수 있다. 캐스케이드 코릴레이션 네트워크에 이 활성화 함수를 사용하여 중요한 기준 문제(benchmark problem)의 하나인 이중나선 문제(two spirals problem)에 대하여 실험하여 다른 활성화 함수들과 결과 값을 비교하였다.

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의사 가우시안 함수 신경망의 설계 (The Design of a Pseudo Gaussian Function Network)

  • 김병만;고국원;조형석
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.16-16
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    • 2000
  • This paper describes a new structure re create a pseudo Gaussian function network (PGFN). The activation function of hidden layer does not necessarily have to be symmetric with respect to center. To give the flexibility of the network, the deviation of pseudo Gaussian function is changed according to a direction of given input. This property helps that given function can be described effectively with a minimum number of center by PGFN, The distribution of deviation is represented by level set method and also the loaming of deviation is adjusted based on it. To demonstrate the performance of the proposed network, general problem of function estimation is treated here. The representation problem of continuous functions defined over two-dimensional input space is solved.

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Linear prediction and z-transform based CDF-mapping simulation algorithm of multivariate non-Gaussian fluctuating wind pressure

  • Jiang, Lei;Li, Chunxiang;Li, Jinhua
    • Wind and Structures
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    • 제31권6호
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    • pp.549-560
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    • 2020
  • Methods for stochastic simulation of non-Gaussian wind pressure have increasingly addressed the efficiency and accuracy contents to offer an accurate description of the extreme value estimation of the long-span and high-rise structures. This paper presents a linear prediction and z-transform (LPZ) based Cumulative distribution function (CDF) mapping algorithm for the simulation of multivariate non-Gaussian fluctuating wind pressure. The new algorithm generates realizations of non-Gaussian with prescribed marginal probability distribution function (PDF) and prescribed spectral density function (PSD). The inverse linear prediction and z-transform function (ILPZ) is deduced. LPZ is improved and applied to non-Gaussian wind pressure simulation for the first time. The new algorithm is demonstrated to be efficient, flexible, and more accurate in comparison with the FFT-based method and Hermite polynomial model method in two examples for transverse softening and longitudinal hardening non-Gaussian wind pressures.

Determination of the Distribution of the Preisach Density Function With Optimization Algorithm

  • Hong Sun-Ki;Koh Chang Seop
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • 제5B권3호
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    • pp.258-261
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    • 2005
  • The Preisach model needs a distribution function or Everett function to simulate the hysteresis phenomena. To obtain these functions, many experimental data obtained from the first order transition curves are usually required. In this paper, a simple procedure to determine the Preisach density function using the Gaussian distribution function and genetic algorithm is proposed. The Preisach density function for the interaction field axis is known to have Gaussian distribution. To determine the density and distribution, genetic algorithm is adopted to decide the Gaussian parameters. With this method, just basic data like the initial magnetization curve or saturation curves are enough to get the agreeable density function. The results are compared with experimental data and we got good agreements comparing the simulation results with the experiment ones.

TEM 관련 이론해설 (2): Fourier 변환 (Fourier Transformations)

  • 이확주
    • Applied Microscopy
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    • 제32권3호
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    • pp.195-204
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    • 2002
  • TEM 이론의 기초가 되는 델타함수, 콘볼루션 적분, 퓨리에 변환에 관한 개념을 소개하고 이에 대한 응용으로 슬릿함수, 현저한 폭을 갖는 2개의 슬릿, 유한 크기의 파동 train, 좁은 슬릿의 주기적인 배열, 임의의 주기 함수, diffraction grating, 회절 격자, 그리고 gaussian 함수에서의 퓨리에 변환에 관한 수학적인 방법의 적용을 소개하였다.

이변량 Gaussian 분포함수를 적용한 CFRP 적층 평판의 보강섬유 물성저하 규명 (Determination of Degraded Fiber Properties of Laminated CFRP Flat Plates Using the Bivariate Gaussian Distribution Function)

  • 김규동;이상열
    • Composites Research
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    • 제29권5호
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    • pp.299-305
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    • 2016
  • 본 연구는 이변량 Gaussian 분포함수를 적용하여 CFRP 적층판의 섬유물성 변화를 추정하는 방법을 제안하였다. 섬유의 손상 분포를 규명하기 위하여 수정된 이변량 Gaussian 분포함수를 적용하여 5개의 미지 변수가 고려되었다. 조합된 컴퓨터 기법을 적용하여 역문제를 해결하기 위하여 본 연구에서는 몇 개의 고유진동수와 모드 정보를 입력데이터로 활용하였다. 수치해석 예제는 제안된 기법이 적층배열 변화에 따른 CFRP 판의 섬유 손상 분포 및 위치를 규명할 수 있는 적합하고 실용적은 방법임을 보여준다.