• 제목/요약/키워드: Coefficient of Variance

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A Noisy Infrared and Visible Light Image Fusion Algorithm

  • Shen, Yu;Xiang, Keyun;Chen, Xiaopeng;Liu, Cheng
    • Journal of Information Processing Systems
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    • 제17권5호
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    • pp.1004-1019
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    • 2021
  • To solve the problems of the low image contrast, fuzzy edge details and edge details missing in noisy image fusion, this study proposes a noisy infrared and visible light image fusion algorithm based on non-subsample contourlet transform (NSCT) and an improved bilateral filter, which uses NSCT to decompose an image into a low-frequency component and high-frequency component. High-frequency noise and edge information are mainly distributed in the high-frequency component, and the improved bilateral filtering method is used to process the high-frequency component of two images, filtering the noise of the images and calculating the image detail of the infrared image's high-frequency component. It can extract the edge details of the infrared image and visible image as much as possible by superimposing the high-frequency component of infrared image and visible image. At the same time, edge information is enhanced and the visual effect is clearer. For the fusion rule of low-frequency coefficient, the local area standard variance coefficient method is adopted. At last, we decompose the high- and low-frequency coefficient to obtain the fusion image according to the inverse transformation of NSCT. The fusion results show that the edge, contour, texture and other details are maintained and enhanced while the noise is filtered, and the fusion image with a clear edge is obtained. The algorithm could better filter noise and obtain clear fused images in noisy infrared and visible light image fusion.

흡기포트 선회비 변경에 따른 유동특성 및 엔진성능에 관한 연구 (A Study on the Flow Characteristics and Engine Performance with Swirl Ratio Variance of Intake Port)

  • 윤준규;차경옥
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집B
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    • pp.899-905
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    • 2000
  • The characteristics of air flow and engine performance with swirl ratio variance of intake port In a turbocharged DI diesel engine was studied in this paper. The intake port flow is important factor which have influence on the engine performance and exhaust emission because the properties in the injected fuel depend on the combustion characteristics. The swirl ratio for ports was modified by hand-working and measured by impulse swirl meter. For the effects on performance and emission, the brake torque and brake specific fuel consumption were measured by engine dynamometer and NOx, smoke were measured by gas analyzer and smoke meter. As a result of steady flow test, when the valve eccentricity ratio are closed to cylinder wall, the flow coefficient and swirl intensity are increased. And as the swirl ratio is increased, the mean flow coefficient is decreasing, whereas the gulf factor is increasing. Also, through engine test its can be expected to meet performance and emission by optimizing the main parameters; the swirl ratio of intake port, injection timing and compression ratio.

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제주화산도의 암석성분에 관한 통계학적인 수치해석 (The Statistical on Numerical Analysis for The Petrology and Bulk Chemical Composition. In Cheju Volcanic Island)

  • 택훈
    • 동굴
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    • 제14권15호
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    • pp.42-90
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    • 1987
  • 제주화산도의 암석학에 대한 암석기재 및 총화학 조성의 63종은 이문원에 의해 보고되고 있다. 총화학조성 데-타는 FORTRAN77의 프로그램에 의해 해석을 하였다. 해석에는 우선 최소자집법에 의해 환산식과 산분도를 검토했다. 다음에 통계적 데-타는 평균치, 최대치, 최소치, 범위, 표준편차, 분산, 표준오차 및 변동계수를 구했다. 표준편차의 큰 단위 물질은 SiO$_2$, MgO 및 FeO이고 작은 단위 물질은 MnO와 P$_2$O$_{5}$이다. 표준오차와 분산은 표준편차와 매우 유사한 조항이 있다. 그렇지만 변동계수는 표준편차와 다르다. 여기에서 큰 단위 변동계수는 $H_2O$$^{-}$$H_2O$$^{+}$이고, 작은 단위 변동계수는 $Al_2$O$_3$ 및 SiO$_2$ 이다. 상관계수의 계산은 정과 부의 상관성을 SiO$_2$, $Al_2$O$_3$ 및 TiO$_2$에 대해서 다른 조성과의 관계를 계산적으로 구할수 있다.

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강인한 음성인식을 위한 극점 필터링 및 스케일 정규화를 이용한 켑스트럼 특징 정규화 방식 (Cepstral Feature Normalization Methods Using Pole Filtering and Scale Normalization for Robust Speech Recognition)

  • 최보경;반성민;김형순
    • 한국음향학회지
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    • 제34권4호
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    • pp.316-320
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    • 2015
  • 본 논문에서는 Cepstral Mean Normalization(CMN)과 Cepstral Mean and Variance Normalization(CMVN) 프레임워크에서 극점 필터링(pole filtering) 개념을 Mel-Frequency Cepstral Coefficient(MFCC) 특징 벡터에 적용한다. 또한 분산 정규화를 대신하여 스케일 정규화를 사용하는 Cepstral Mean and Scale Normalization(CMSN)의 성능을 잡음 환경 음성인식 실험을 통해 평가한다. CMN과 CMVN은 보통 발화 단위로 수행되기 때문에 짧은 발화의 경우 특징에 대한 평균과 분산의 추정 신뢰도가 보장되지 않는 문제점을 가지는데, 극점 필터링과 스케일 정규화 방식을 적용함으로 이러한 문제점을 보완할 수 있다. Aurora 2 데이터베이스를 이용한 실험 결과, 극점 필터링과 스케일 정규화를 결합한 특징 정규화 방식의 성능이 가장 높은 성능 향상을 보인다.

인삼 주요형질의 변이계수 (Coefficient of Variability of Agronomic Characters in Panax ginseng C.A. Meyer)

  • 안상득;최광태
    • Journal of Ginseng Research
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    • 제9권1호
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    • pp.9-14
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    • 1985
  • The aerial parts, stem diameter, stem length, Petiole length, leaf length and leaf width were investigated to estimate coefficient of variability in ginseng at 2 to 4 years grown under the conventional and improved shadings. C.V values of characters such as stem length, petiole length, leaf length and leaf width were decreased with increasing the plant age, while that of steam diameter was increased. C.V. values of aerial part characters were higher in conventional shading than in improved shading, and the variance of c.v. was not significant when above 20 plants were investigated.

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l-STEP GENERALIZED COMPOSITE ESTIMATOR UNDER 3-WAY BALANCED ROTATION DESIGN

  • KIM K. W.;PARK Y. S.;KIM N. Y.
    • Journal of the Korean Statistical Society
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    • 제34권3호
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    • pp.219-233
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    • 2005
  • The 3-way balanced multi-level rotation design has been discussed (Park Kim and Kim, 2003), where the 3-way balancing is done on interview time, in monthly sample and rotation group and recall time. A greater advantage of 3-way balanced design is accomplished by an estimator. To obtain the advantage, we generalized previous generalized composite estimator (GCE). We call this as l-step GCE. The variance of the l-step GCE's of various characteristics of interest are presented. Also, we provide the coefficients which minimize the variance of the l-step GCE. Minimizing a weighted sum of variances of all concerned estimators of interest, we drive one set of the compromise coefficient of l-step GCE's to preserve additivity of estimates.

BAYESIAN MODEL AVERAGING FOR HETEROGENEOUS FRAILTY

  • Chang, Il-Sung;Lim, Jo-Han
    • Journal of the Korean Statistical Society
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    • 제36권1호
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    • pp.129-148
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    • 2007
  • Frailty estimates from the proportional hazards frailty model often lead us to conjecture the heterogeneity in frailty such that the variance of the frailty varies over different covariate groups (e.g. male group versus female group). For such systematic heterogeneity in frailty, we consider a regression model for the variance components in the proportional hazards frailty model, denoted by the MLFM. However, in many cases, the observed data do not show any statistically significant preference between the homogeneous frailty model and the heterogeneous frailty model. In this paper, we propose a Bayesian model averaging procedure with the reversible jump Markov chain Monte Carlo which selects the appropriate model automatically. The resulting regression coefficient estimate ignores the model uncertainty from the frailty distribution in view of Bayesian model averaging (Hoeting et al., 1999). Finally, the proposed model and the estimation procedure are illustrated through the analysis of the kidney infection data in McGilchrist and Aisbett (1991) and a simulation study is implemented.

CONFIDENCE INTERVALS ON THE AMONG GROUP VARIANCE COMPONENT IN A REGRESSION MODEL WITH AN UNBALANCED ONE-FOLD NESTED ERROR STRUCTURE

  • 박동준
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2002년도 추계 학술발표회 논문집
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    • pp.141-146
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    • 2002
  • In this article we consider the problem of constructing confidence intervals for a linear regression model with nested error structure. A popular approach is the likelihood-based method employed by PROC MIXED of SAS. In this paper, we examine the ability of MIXED to produce confidence intervals that maintain the stated confidence coefficient. Our results suggest the intervals for the regression coefficients work well, but the intervals for the variance component associated with the primary level cannot be recommended. Accordingly, we propose alternative methods for constructing confidence intervals on the primary level variance component. Computer simulation is used to compare the proposed methods. A numerical example and SAS code are provided to demonstrate the methods.

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The Prediction of the Expected Current Selection Coefficient of Single Nucleotide Polymorphism Associated with Holstein Milk Yield, Fat and Protein Contents

  • Lee, Young-Sup;Shin, Donghyun;Lee, Wonseok;Taye, Mengistie;Cho, Kwanghyun;Park, Kyoung-Do;Kim, Heebal
    • Asian-Australasian Journal of Animal Sciences
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    • 제29권1호
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    • pp.36-42
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    • 2016
  • Milk-related traits (milk yield, fat and protein) have been crucial to selection of Holstein. It is essential to find the current selection trends of Holstein. Despite this, uncovering the current trends of selection have been ignored in previous studies. We suggest a new formula to detect the current selection trends based on single nucleotide polymorphisms (SNP). This suggestion is based on the best linear unbiased prediction (BLUP) and the Fisher's fundamental theorem of natural selection both of which are trait-dependent. Fisher's theorem links the additive genetic variance to the selection coefficient. For Holstein milk production traits, we estimated the additive genetic variance using SNP effect from BLUP and selection coefficients based on genetic variance to search highly selective SNPs. Through these processes, we identified significantly selective SNPs. The number of genes containing highly selective SNPs with p-value <0.01 (nearly top 1% SNPs) in all traits and p-value <0.001 (nearly top 0.1%) in any traits was 14. They are phosphodiesterase 4B (PDE4B), serine/threonine kinase 40 (STK40), collagen, type XI, alpha 1 (COL11A1), ephrin-A1 (EFNA1), netrin 4 (NTN4), neuron specific gene family member 1 (NSG1), estrogen receptor 1 (ESR1), neurexin 3 (NRXN3), spectrin, beta, non-erythrocytic 1 (SPTBN1), ADP-ribosylation factor interacting protein 1 (ARFIP1), mutL homolog 1 (MLH1), transmembrane channel-like 7 (TMC7), carboxypeptidase X, member 2 (CPXM2) and ADAM metallopeptidase domain 12 (ADAM12). These genes may be important for future artificial selection trends. Also, we found that the SNP effect predicted from BLUP was the key factor to determine the expected current selection coefficient of SNP. Under Hardy-Weinberg equilibrium of SNP markers in current generation, the selection coefficient is equivalent to $2^*SNP$ effect.

초장파에 의한 이종재 마찰용접 강도해석 가능성에 관한 연구 (A Feasibility Study on Dissimilar Metals Friction Weld Strength Analysis by Ultrasonic Techniques)

  • 오세규;김동조
    • Journal of Welding and Joining
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    • 제4권2호
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    • pp.47-52
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    • 1986
  • Friction Welds are formed by the mechanisms of diffusion as well as mechanical inter-locking. The severe plastic flow at the interface by the forge action of the process brings the subsurface so close together that detection of any unbounded area becomes very difficult. No reliable method is available so fat to determine the weld quality nondestructively. The paper presents an attempt to determine weld strength quantitatively using the ultrasonic pulseecho method. The new approach calculates the coefficient of reflection based on measured amplitudes of the echoes. This coefficient provides a single quantitative measurement which involves both acoustic energy reflected at the welded interface as well as transmitted across the interface. As a result, it was known that the quantitative relationship between the coefficient and the weld strength (torsional strength) could be drawn.

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