• Title/Summary/Keyword: 가중함수

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Extracting Wisconsin Breast Cancer Prediction Fuzzy Rules Using Neural Network with Weighted Fuzzy Membership Functions (가중 퍼지 소속함수 기반 신경망을 이용한 Wisconsin Breast Cancer 예측 퍼지규칙의 추출)

  • Lim Joon Shik
    • The KIPS Transactions:PartB
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    • v.11B no.6
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    • pp.717-722
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    • 2004
  • This paper presents fuzzy rules to predict diagnosis of Wisconsin breast cancer using neural network with weighted fuzzy membership functions (NNWFM). NNWFM is capable of self-adapting weighted membership functions to enhance accuracy in prediction from the given clinical training data. n set of small, medium, and large weighted triangular membership functions in a hyperbox are used for representing n set of featured input. The membership functions are randomly distributed and weighted initially, and then their positions and weights are adjusted during learning. After learning, prediction rules are extracted directly from the enhanced bounded sums of n set of weighted fuzzy membership functions. Two number of prediction rules extracted from NNWFM outperforms to the current published results in number of rules and accuracy with 99.41%.

Locally Weighted Polynomial Forecasting Model (지역가중다항식을 이용한 예측모형)

  • Mun, Yeong-Il
    • Journal of Korea Water Resources Association
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    • v.33 no.1
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    • pp.31-38
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    • 2000
  • Relationships between hydrologic variables are often nonlinear. Usually the functional form of such a relationship is not known a priori. A multivariate, nonparametric regression methodology is provided here for approximating the underlying regression function using locally weighted polynomials. Locally weighted polynomials consider the approximation of the target function through a Taylor series expansion of the function in the neighborhood of the point of estimate. The utility of this nonparametric regression approach is demonstrated through an application to nonparametric short term forecasts of the biweekly Great Salt Lake volume.volume.

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A Study on Objective Functions for the Multi-purpose Dam Operation Plan in Korea (국내 다목적댐 운영계획에 적합한 목적함수에 관한 연구)

  • Eum, Hyung-Il;Kim, Young-Oh;Yun, Ji-Hyun;Ko, Ick-Hwan
    • Journal of Korea Water Resources Association
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    • v.38 no.9 s.158
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    • pp.737-746
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    • 2005
  • Optimization is a process that searches an optimal solution to obtain maximum or minimum value of an objective function. Many researchers have focused on effective search algorithms for the optimum but few researches were interested in establishing the objective function. This study compares two approaches for the objective function: one allows a tradeoff among the objectives and the other does not allow a tradeoff by assigning weights for the absolute priority between the objectives. An optimization model using sampling stochastic dynamic programming was applied to these two objective functions and the resulting optimal policies were compared. As a result, the objective function with no tradeoff provides a decision making process that matches practical reservoir operations than that with a tradeoff allowed. Therefore, it is more reasonable to establish the objective function with no a tradeoff among the objectives for multi-purpose dam operation plan in Korea.

A Bayesian Method to Semiparametric Hierarchical Selection Models (준모수적 계층적 선택모형에 대한 베이지안 방법)

  • 정윤식;장정훈
    • The Korean Journal of Applied Statistics
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    • v.14 no.1
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    • pp.161-175
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    • 2001
  • Meta-analysis refers to quantitative methods for combining results from independent studies in order to draw overall conclusions. Hierarchical models including selection models are introduced and shown to be useful in such Bayesian meta-analysis. Semiparametric hierarchical models are proposed using the Dirichlet process prior. These rich class of models combine the information of independent studies, allowing investigation of variability both between and within studies, and weight function. Here we investigate sensitivity of results to unobserved studies by considering a hierachical selection model with including unknown weight function and use Markov chain Monte Carlo methods to develop inference for the parameters of interest. Using Bayesian method, this model is used on a meta-analysis of twelve studies comparing the effectiveness of two different types of flouride, in preventing cavities. Clinical informative prior is assumed. Summaries and plots of model parameters are analyzed to address questions of interest.

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Generalized Weighted Linear Models Based on Distribution Functions - A Frequentist Perspective (분포함수를 기초로 일반화가중선형모형)

  • 여인권
    • The Korean Journal of Applied Statistics
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    • v.17 no.3
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    • pp.489-498
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    • 2004
  • In this paper, a new form of linear models referred to as generalized weighted linear models is proposed. The proposed models assume that the relationship between the response variable and explanatory variables can be modelled by a distribution function of the response mean and a weighted linear combination of distribution functions of covariates. This form addresses a structural problem of the link function in the generalized linear models in which the parameter space may not be consistent with the space derived from linear predictors. The maximum likelihood estimation with Lagrange's undetermined multipliers is used to estimate the parameters and resampling method is applied to compute confidence intervals and to test hypotheses.

An Adaptive Control of Symmetry Contribution Based Generalized Symmetry Transform (적응적 대칭기여도 제어 기반 일반화 대칭변환)

  • Jeon, Joon-Hyung;Lee, Seung-Hee;Park, Kil-Houm
    • Journal of Korea Multimedia Society
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    • v.17 no.2
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    • pp.208-217
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    • 2014
  • This paper propose an adaptive control of symmetry contribution based generalized symmetry transform. which can be controlled symmetry contribution according to the intensity orientation of two pixels. In the proposed method, we define the C-D(convergent and divergent)plane which represents convergence and divergence region of gradient pairs. and used the gaussian phase wight function, with respect to the distance from the gradient pair to an extreme point, in calculating the symmetry contribution. The proposed method can be detect the object more efficiently by adaptive controlling the cut-off frequency of the gaussian phase wight function. To evaluate a performance of the proposed method, we compare the proposed method and conventional GST method in various images including IR image. we prove that the proposed method have better performance in object detection.

Reliability Analysis of Fuzzy Systems With Weighted Components Using Vague Sets (모호집합을 이용한 가중 구성요소를 갖는 퍼지시스템의 신뢰도 분석)

  • Cho, Sang-Yeop;Park, Sa-Joon
    • Journal of KIISE:Software and Applications
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    • v.33 no.11
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    • pp.979-985
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    • 2006
  • In the conventional researches, the reliabilities of the fuzzy system are represented and analyzed by real values between zero and one, fuzzy numbers, intervals of confidence, etc. In this paper, we present a method to represent and analyze the reliabilities of the weighted components of the fuzzy system and the weights reflected on their importance based on vague sets defined in the universe of discourse [0, 1]. The vague set is represented as the interval consisted of the truth-membership functions and the false-membership functions, therefore it can allow the reliabilities and the weights of a fuzzy system to represent in a more flexible manner. The proposed method considers the weights of the weighted components in the fuzzy systems, its reliability analysis is more flexible and effective than the conventional methods.

Voice Source Modeling Using Weighted Sum-of-Basis-Functions Model (기저함수의 가중합을 이용한 음원의 모델링)

  • 강상기
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1998.06c
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    • pp.171-174
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    • 1998
  • 본 논문에서는 음성합성(speech synthesis) 및 부호화(coding) 시스템에 있어서 음원(voice source) 모델링에 관한 문제를 살펴보고자 한다. 기존의 음원 모델링 시스템이 가지고 있는 여러 문제들을 극복하고자 기저함수(basis function) 의 가중 합(weighted-sum)으로 음원을 모델링 하는 새로운 기법을 제안하고자 한다. 제안한 방법에서는 음원 파형(voice source waveform)을 적절히 표현하기 위해서 필터뱅크(filter bank)에 기초한 기저함수의 가중 합으로 나타낸다. 다양한 음원 특성을 효과적으로 나타내는 음원 파라미터를 구하기 위하여 EM(estimate maximize)에 기초한 구조에 관해 조사한다. 제안한 방법을 이용하여 다양한 유성음에 대해 실험을 수행하였다. 실험결과 제안한 추정(estimation) 방법 및 모델링 방법을 이용하면 기존의 방법에 비해 더 정확한 음원 파형을 추정할 수 있고, 다양한 음원 특성을 나타낼 수 있다. 또한 음성합성 및 부호화에서도 음성품질(voice quality)를 개선시킬 수 있으리라 기대된다.

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Calculation of Stress Intensity Factors Using Single-Layer Potential and Weight Function (Single-Layer 포텐셜과 가중함수를 이용한 응력강도계수의 계산)

  • 이형연;홍창선
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.4
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    • pp.981-989
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    • 1995
  • A new weight function approach to determine SIF(stress intensity factor) using single-layer potential has been presented. The crack surface displacement field was represented by one boundary integral term whose kernel was modified from Kelvin's fundamental solution. The proposed method enables the calculation of SIF using only one SIF solution without any modification for the crack geometries symmetric in two-dimensional plane such as a center crack in a plate with or without an internal hole, double edge cracks, circumferential crack or radial cracks in a pipe. The application procedure to those crack problems is very simple and straightforward with only one SIF solution. The necessary information in the analysis is two reference SIFs. The analysis results using present closed-form solution were in good agreement with those of the literature.