• Title/Summary/Keyword: Variance of Analysis

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Optimization of a geometric form and cutting conditions of a metal slitting saw by experimental method (실험적 방법을 통한 Metal slitting saw의 형상 및 절삭 조건의 최적화)

  • 정경득;고태조;김희술
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.05a
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    • pp.934-938
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    • 2000
  • Built-up edge affects the surface integrity of the machined surface and tool wear. Tool geometry and cutting conditions are very important factors to remove BUE. In this paper, we optimized the geometry of the metal slitting saw .1nd cutting conditions to remove BUE by the experiment. In general, the metal slitting saw is plain milling cutter with thickness less of a 3/16 inch. This is used for cutting workpiece where high dimensional accuracy and surface finish are necessary. The experiment was planned with Taguchi method that is based on the orthogonal array of design factors(coating, rake angle, number of tooth, cutting speed, feed rate). Response table was made by the value of the surface roughness, the optimized tool geometry and cutting conditions through response table could be determined. In addition. the relative effect of factors were identified by the variance analysis. filially. coating and cutting speed turned out important factors.

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Estimation of Gini-Simpson index for SNP data

  • Kang, Joonsung
    • Journal of the Korean Data and Information Science Society
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    • v.28 no.6
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    • pp.1557-1564
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    • 2017
  • We take genomic sequences of high-dimensional low sample size (HDLSS) without ordering of response categories into account. When constructing an appropriate test statistics in this model, the classical multivariate analysis of variance (MANOVA) approach might not be useful owing to very large number of parameters and very small sample size. For these reasons, we present a pseudo marginal model based upon the Gini-Simpson index estimated via Bayesian approach. In view of small sample size, we consider the permutation distribution by every possible n! (equally likely) permutation of the joined sample observations across G groups of (sizes $n_1,{\ldots}n_G$). We simulate data and apply false discovery rate (FDR) and positive false discovery rate (pFDR) with associated proposed test statistics to the data. And we also analyze real SARS data and compute FDR and pFDR. FDR and pFDR procedure along with the associated test statistics for each gene control the FDR and pFDR respectively at any level ${\alpha}$ for the set of p-values by using the exact conditional permutation theory.

A Study on the Forecasting of Decision Behavior the Choice of Housing of Potential Purchasers in Bukgu New Housing Area, Ulsan (울산시 북구 신주거지역의 아파트 계획을 위한 북구 거주자의 주거선택행동 예측)

  • Kim, Sun-Joong;Kwon, Myung-Hee
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2004.11a
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    • pp.89-96
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    • 2004
  • The purpose of the study was to identify the status of satisfaction level, moving motivation, the level of housing choosing behavior, and housing needs of potential purchasers in bukgu new housing area, Ulsan. The survey used questionnaire from 336 households living in bukgu area and analyzed using descriptive statistics, and one-way analysis of variance and Scheffe' multiple range test. The research results showed low degree of residents' satisfaction in storage space, neighborhood environment. The moving motivations were physical environment improvement, education environment, walking road, view and lighting.

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Knowledge and Performance of Developmentally Supportive Positioning for Premature Infants among Neonatal Intensive Care Unit Nurses (신생아집중치료실 간호사의 미숙아 체위지지 간호에 대한 지식 및 수행)

  • Kim, Min-Jung;Kim, Tae-Im
    • Child Health Nursing Research
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    • v.24 no.2
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    • pp.229-240
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    • 2018
  • Purpose: This study was conducted to assess the knowledge and performance of developmentally supportive positioning for premature infants (DSPP) among neonatal intensive care unit (NICU) nurses. Methods: The participants in this study were 131 nurses working in the NICU at five university hospitals in Daejeon and the city of Cheong-ju. The collected data were analyzed with descriptive statistics, the t-test, analysis of variance, and Pearson correlation coefficients using SPSS for Windows version 22.0. Results: NICU nurses' average DSPP knowledge score was 24.7 out of 33.0, and their average DSPP performance score was 3.2 out of 4.0. A statistically significant positive correlation was observed between knowledge and performance of DSPP (r=.32, p<.001). Conclusion: To improve the level of NICU nurses' knowledge and performance of DSPP, educational programs should be developed and their effectiveness should be verified.

Effect of Manufacturing Conditions on the Properties of Oil-absorbable Melt Blown Nonwoven (멜트블로운 부직포 제조공정이 유흡착포의 특성에 미치는 영향)

  • Shin, Hyun-Sae;Jin, Lu;Yoo, Joo-Hwan
    • Textile Coloration and Finishing
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    • v.21 no.6
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    • pp.22-28
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    • 2009
  • Oil-absorbable nonwovens were produced by melt-blown processing of polypropylene chips. The melt-blown processing conditions, such as air pressure, and gear pump speed, DCD. In this study, these three factors were chosen to produce samples. Experimental array and variance analysis of the design of experiment were used to increase the field repeatability and universality. The effect of the factors on oil absorption properties of melt-blown nonwoven fabric such as oil absorbency were evaluated. As a result, the fiber diameter decreased as gearpump speed decreased or air pressure increased. The oil absorbency increased as air pressure increased or gearpump speed decreased and with the DCD increasing the oil absorbency significantly increased.

Dynamic Characteristic Improvement of the Plate Spring in a 2-axis Small Sized Actuator (2축 소형 구동기 판 스프링의 동특성 개선)

  • Park, Soon-Ok;Yoo, Jeong-Hoon;Park, No-Cheol
    • Transactions of the Society of Information Storage Systems
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    • v.5 no.1
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    • pp.14-18
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    • 2009
  • This paper proposed an optimal plate spring design for the optical image stabilizer in mobile phones. The voice-coil motor (VCM) with plate spring is the smallest, lowest-cost solution for auto focus on the market today and it is also the simplest to implement. The VCM is selected in this paper for auto focusing. However, the design process is complex due to the many design variables coupled to each other and some constraints of each directional motion caused by the characteristics of plate spring. Because of the complex formulation of the design objective, a plate spring design is proposed through the design of experiments to find the optimal design satisfying design constraints.

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Biaxial Fracture Behavior of Alumina Ceramics ; Thickness Effect on Ball-on-3-ball Test (시편 두께에 따른 알루미나 세라믹스의 이축 파괴 거동)

  • 이홍림;박성은;이중현
    • Journal of the Korean Ceramic Society
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    • v.36 no.7
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    • pp.711-717
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    • 1999
  • Biaxial fracture behavior of alumina specimens with the diameter of 20mm and four kinds of thickness of 1.9, 2.3, 2.6 and 2.8mm was studied by the ball-on-3-ball test and the fracture results were analyzed by he analysis of variance (ANOCA), The strength measured with the down speed prescribed in ASTM showed that the measured strength was not dependent on the thickness of the specimens. Equivalent radius and crack-braching number were observed to increase lineraly with the thickness of the specimens. The jog direction was observed to study the effect of grinding direction on surface flaws. It is though that the surface finishing with #600 grit diamond wheel did not affect the surface flaws of the specimens.

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Heritability and Genetic Gains for Height Growth in 20-year-Old Korean White Pine in Korea

  • Shin, Man-Yong;Park, Hyung-Soon;Cho, Yoon-Jin;Chung, Dong-Jun
    • Korean Journal of Plant Resources
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    • v.19 no.6
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    • pp.677-679
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    • 2006
  • The objectives of this study were to examine the genetic variation of 20-year-old tree height and to estimate heritabilities and genetic gains of Korean white pine. Analysis of variance showed that families and family x block interaction had the significant (p=0.01) effects on tree height. However, family variation appears to be much greater than the variation due to family x block interaction. Individual tree heritability was higher ($h_I^2=0.73$) than family heritability, ($h_F^2=0.83$) therefore, combined selection showed the largest genetic gain (17.76%) in a given equal intensity of selection.

A study on the Development of the Family Functioning Scale -On the basis of FFS developed by Tavitian et al.- (가족기능도 척도' 개발에 관한연구 -Tavitian Lubiner green grebstein Velicer의 가족기능도 척도(FFS)에 기초하여-)

  • 유영주
    • Journal of Families and Better Life
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    • v.17 no.1
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    • pp.57-72
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    • 1999
  • The purpose of this study was to develop wholistic Family Functioning Scale for Korean family bases on FFS of Tavitian et al. The data for this study was got from the sample survey of 370 mothers who had children of education period living in Seoul and kyunggi-do. The major findings were summarized as follows: 1) Through item discrimination method 34 items of the total items showed a high index ranged from .29. to .77 of discrimination coefficient 2) Factor analytic procedures selected 29 items among 34 items and extracted 4 factors(Positive Fmaily Emotion Family Communication Participation in Family Event and Sharing Family Worries) These factors accounted for 93.03% of the total variance. 3) A multiple regression analysis conducted to reduce the number of items yielded 26 items for the Family Functioning Scale 4) Internal consistency reliability for this scale showed high internal consistency(Cronbach's a= .86)

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Analysis of Difference Between the Process Capability Indices and the Process Incapability Indices. (공정능력지수와 비공정능력지수의 차이분석)

  • 양정문;이보근;김정자
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.21 no.45
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    • pp.347-356
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    • 1998
  • For assessing the capability of a process, the quantification of process location and variation is central to understanding the quality of units produced from the manufacturing process. Conventional process capability indices is insufficient to drive out the information for process condition, furthermore it is very difficult to evaluate the process capability accurately when the target value is not consistent with the center of specification, and/or the shape of distribution is changed, but the process incapability indices is enable to provide more detailed information to evaluate the process capability by dividing information about the process mean and variance. In this paper, we have a brief review and comparison about these indices, provide an understanding of the relationships between the process capability indices and the incapability indices. And we explore the strengths and weakness of these indices as they apply to normally distributed process, and to examine the effect that non-normality has on these indices.

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