• Title/Summary/Keyword: the process variables

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공정변수를 갖는 혼합물 실험에서 모형선택의 한 방법 (A Note on Model Selection in Mixture Experiments with Process Variables)

  • 김정일
    • 응용통계연구
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    • 제26권1호
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    • pp.201-208
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    • 2013
  • 이 논문에서는 공정변수를 갖는 혼합물 실험에 대하여 적절한 모형을 선택하는 한 방법으로 혼합물 성분의 공선성에 로버스트한 성질을 갖는 마할라노비스-다구찌 시스템을 활용한 전략을 소개한다. 여러 문헌에서 언급된 3개의 혼합물 성분과 2개의 공정변수를 갖는 제빵 실험 사례를 대상으로 이 전략적 방법을 적용하여 적절한 모형을 선택하였다.

A STRONG LAW OF LARGE NUMBERS FOR AANA RANDOM VARIABLES IN A HILBERT SPACE AND ITS APPLICATION

  • Ko, Mi-Hwa
    • 호남수학학술지
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    • 제32권1호
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    • pp.91-99
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    • 2010
  • In this paper we introduce the concept of asymptotically almost negatively associated random variables in a Hilbert space and obtain the strong law of large numbers for a strictly stationary asymptotically almost negatively associated sequence of H-valued random variables with zero means and finite second moments. As an application we prove a strong law of large numbers for a linear process generated by asymptotically almost negatively random variables in a Hilbert space with this result.

유한요소해석을 이용한 Mg 합금 판재 성형 공정 변수 분석 (FEM analysis for process variables in sheet metal forming for Mg alloy)

  • 이영선;권용남;이정환
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.1082-1086
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    • 2004
  • Since the sheet forming of Mg alloy has many difficulties due to the low formability, many forming conditions need to be selected properly. Especially, the process variables should be investigated to increase the formability, such as, forming temperature. In this paper, the effects of forming process variables has been investigated using the bending and deep drawing process. A simple U-bending designed for mobile part could be formed in room temperature and springback amounts are surveyed. On the other hand, square cup part couldn't be formed in room temperature due to the low formability. Therefore, the effects of forming temperature are investigated in deep drawing process for square cup part. As a experimental and FEM results, the optimum forming temperature is presence and formability in a higher temperature is less than that of lower temperature. Above experimental results are compared with the FEM analysis and well coincided with the experimental results. Therefore, more detail investigations could be progressed to select more appropriate process conditions by the FEA.

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순서형 변수를 위한 관리도 (Control Charts for Ordinal Variables)

  • 장대홍
    • 한국품질경영학회:학술대회논문집
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    • 한국품질경영학회 2006년도 춘계학술대회
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    • pp.330-333
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    • 2006
  • Many practical problems of quality control in service management are derived from the use of ordinal variables. Ordered linguistic variables differ from measurement variables. This paper presents a new control chart of a production process based on ordinal variables.

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타원형 디프 드로잉 공정에서 블랭크의 기하학적 형상에 관한 연구 (A Study on the Geometrical shape of Blank in Elliptical Deep Drawing)

  • 박동환
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2000년도 춘계학술대회논문집
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    • pp.146-150
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    • 2000
  • there are a lot of process variable exerted influence on the formability of products in deep drawing process. Particularly it is important that blank shape of the process variables. A paper to be connected with process variables of elliptical deep drawing products is insufficient the actual circumstances enough though researches have been performed on the deep drawing of sheet metal forming. In this study The effects of thickness distribution and movement of sheet are grasped as alteration of blank shapes in the process of elliptical deep drawing product and then optimal blank shape was presented. They were verified by the finite element analysis (FEA) and experiment.

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타원형 디프 드로잉 공정에서 블랭크 형상의 영향에 관한 연구 (A Study on the Influence of Blank Shape in Elliptical Deep Drawing Process)

  • 박동환;배원락;박상봉;강성수
    • 소성∙가공
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    • 제9권5호
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    • pp.469-477
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    • 2000
  • Most of researches have been performed on the formability of axisymmetric shape, but it is insufficient that the study on Process variables of elliptical deep drawing Product. There are many Process variables exerted influence on the formability of products. Particularly, blank shape is more important than the others in elliptical deep drawing process. In this study, blanks of three types were proposed and compared using thickness distribution and movement of sheet during the process. The aim of a paper is to obtain optimal blank shape through experiment and finite element analysis(FEA).

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의복에 대한 태도와 가정환경변인과의 관계연구 -부산.경남지역의 남.녀 대학생을 중심으로- (The Relation between the Value Orientations of family, the Psychological Process of Family and Clothing Atitudes)

  • 이경희
    • 대한가정학회지
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    • 제26권3호
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    • pp.33-42
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    • 1988
  • The study was to investigate the relationship between clothing variables (Conformity, Modesty, Importance) and environmental variables of Family (the Value Orientations of Family, the Psychological Process of Family), according to sex and region. the subjects were university students in Kyoung nam and Pusan (Male; 397-Pusan 183 and Kyoung nam 214, Female; 401-Pusan 224 and Kyoung Nam 177). Survey method was questionnaires. The data was analyzed with frequency, Pearson's Parson's Correlation, T-test, Multiple Regression using the SPSS. The results were as follows; 1. There was significant difference between clothing Variables in Young nam, but partially significant difference in Pusan. 2. There was partially significant difference between clothing Variables and Environmental Variables of family in each male & female Kyoung nam & Pusan). 3. In the T-test, between clothing Variables and Environmental Variables of family, difference between male and female was shown that female student was higher than male student all of Clothing Variables and male student was higher than female student t in the case of Environmental Variables of family, In the difference between Pusan and Kyoung Nam, male student was shown significant difference in the case of Conformity, materialism and love-Rejection, female student in the case of Modesty, Importance, materialism and Social rising. 4. In the multiple Regression analysis between clothing variables and Environmental Variables of family, clothing voriables partially were effected on the Environmental Variables of family in the cases of male and female in Pusan & Kyoung Nam.

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적외선센서를 이용한 용접품질 제어에 관한 연구 (A Study on the Control of the Welding Quality Using a Infrared sensor)

  • 김일수;손준식;김학형;서주환;김인주
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 추계학술대회 논문집
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    • pp.754-758
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    • 2005
  • Optimization of process variables such as arc current, welding voltage and welding speed in terms of the weld characteristics desired is the key step in achieving high quality and improving performance characteristics without increasing the cost. Consequently, incorrect settings of those process variables give rise to deviations in the welding characteristics from the desired bead geometry. Therefore, trainee welders are referred to the tabulated information relating different metal types and thickness as to recommend the desired values of process variables. Basically, the bead geometry plays an important role in determining the mechanical properties of the weld. So that it is very important to select the process variables for obtaining optimal bead geometry. However, it is difficult for the traditional identification methods to provide an accurate model because the optimized welding process is non-linear and time-dependent. In this paper, the possibilities of the Infra-red sensor in sensing and control of the bead geometry in the automated welding process are presented. Infra-red sensor is a well-known method to deal with the problems with a high degree of fuzziness so that the sensor is employed to build the relationship between process variables and the quality characteristic the proposed above respectively. Based on several neural networks, the mathematical models are derived from extensive experiments with different welding parameters and complex geometrical features. The developed system enables to select the optimal welding parameters and control the desired weld dimensions during arc welding process.

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원형컵 드로잉 공정에 미치는 영향인지에 관한 실험적 연구 (Experimental Study on the Parameters Affect Cylindrical Cup Drawing Process)

  • 정동원;양경부;김광희
    • 소성∙가공
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    • 제8권5호
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    • pp.449-453
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    • 1999
  • Sheet metal forming process is a non-linearity problem which is affected by various process variables, such as geometric shape of punch and die, frictional characteristic, etc.. Therefore, the knowledge of the influence of the process variables is needed in the design of sheet metal working processes. In this paper, cylindrical cup drawing tests for blank holding force, punch speed and lubrication between sheet material and tool were carried out to investigate the influence upon sheet formability. Experimental results were discussed about the defects on the deformation behaviors during the forming process.

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습식 다단 인발공정 해석 프로그램 개발 (Development of Analysis Program for Multi-Pass Wet Wire Drawing Process)

  • 이상곤;김병민;김민안;박병권
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2001년도 추계학술대회 논문집
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    • pp.216-219
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    • 2001
  • The production of fine wire through multi-pass wet wire drawing process would be impossible with no backtension at inlet of dies. Backtension is affected by many process parameters, such as dies reduction, coiling number of wire at capstan, machine constant, slip between wire and capstan, characteristic of lubricant and so on. Up to date, dies design and dies pass schedule of multi-pass wet wire drawing process have performed by trial and error of expert in the Industrial field without consideration of quantitative relation among process variables. Thus study investigates the multi-pass wet wire drawing process considering the relation among process variables, such as dies reduction, coiling number of wire at capstan, machine constant, slip between wire and capstan, etc. And analysis program which can analyze many important process values(drawing force, backtension force, slip rate, slip velocity rate, etc) for die design and dies pass schedule of multi-pass wet wire drawing process was developed.

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