• 제목/요약/키워드: control variables

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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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대기행렬 네트워크 시뮬레이션에서 분지확률 통제변수의 응용 (Application of Control Variable with Routing Probability to Queueing Network Simulation)

  • 권치명;임상규
    • 한국시뮬레이션학회논문지
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    • 제21권3호
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    • pp.71-78
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    • 2012
  • 본 연구는 대기행렬 네트워크 시뮬레이션에서 통제변수를 활용하여 목표 반응변수를 보다 더 정확히 추정하는 기법을 탐색한다. 반응변수 추정에서 통제변수기법의 효율성은 반응변수와 높은 상관관계를 가지는 통제변수의 선택과 선택된 통제변수를 이용하여 통제추정량을 어떻게 정의하는가에 따라 달라진다. 대기행렬 네트워크 시뮬레이션 모형에서 확률적 모형의 발전과정은 확률적 서비스시간과 분지 확률에 의하여 재현된다. 대부분의 통제변수기법은 통제추정치 구성에서 서비스 시간 확률변수를 사용한다. 본 연구는 서비스 시간 확률변수와 분지 확률변수를 동시에 사용하는 통제 추정량을 제안하고 이를 컴퓨터 네트워크 시스템의 관심 반응변수 추정에 응용하여 그 효율성을 탐색하고자 한다. 시뮬레이션 결과는 반응변수 추정에 있어서 분지확률 통제변수의 활용 가능성을 제시하고 있으며, 서비스-시간과 분지확률을 동시에 이용하는 결합 통제변수의 활용은 향후 연구가 필요한 분야로 판단된다.

여자청소년의 신체관련변인, 자존감, 내적통제력이 섭식장애행동에 미치는 영향 (The Effect of Female Adolescent Body-Related Variables, Self-Esteem and Internal Control on Eating Disorder Behavior)

  • 김갑숙;강연정
    • 가정과삶의질연구
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    • 제25권3호
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    • pp.77-87
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    • 2007
  • This study purports to understand the direct and indirect effects between eating disorder behavior of female adolescents and their body-related variables(concerning the degree of diet regime, weight control, body satisfaction, and obesity), self-esteem and internal control, by checking three sub-categorized behavior of eating disorders of diet behavior, bulimia behavior, and eating control behavior. The sample group used for the study consisted of 190 female high school students and 292 female university students; measurement devices used for the study were those of body-related variables, self esteem and internal control, and eating disorder behavior; and data analysis was performed using ${\chi}2$, t-test, Pearson's correlation, regression analysis and path analysis. The results are as follows. First, there is a significant difference between university students and high school students regarding their body satisfaction, weight control experience, and self esteem. University students are more satisfied with their body, have higher self esteem, and control their weight better than high school students. Second, diet behavior shows a correlation with the degree of diet interest, weight control experience, and body satisfaction. Body satisfaction and internal control proved to be correlated with bulimia behavior, while weight control experience, obesity, and self esteem were correlated with eating control behavior. Third, the variables that showed a direct influence on diet behavior as an eating disorder are diet interest, weight control experience, body satisfaction and obesity, in that the explanatory power of the variables is 60.7% with the highest mark on obesity. The variables that showed effects on bulimia are body satisfaction and internal control with an explanatory power of 2.8%. Indirect variables effecting bulimia include objects, diet interest, body satisfaction, and self esteem. The variable with a direct influence on eating control behavior was self esteem with and explanatory power of 4%, whereas the variables of objects, diet interest, body satisfaction, weight control experience, and internal control were all indirectly correlated with eating control behavior.

Nonlinear adaptive control for multivariable system

  • Song, Sukheung
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.60.4-60
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    • 2002
  • Nonlinear adaptive control for the laboratory pressure-flow model. Control valves are installed on both sides. The pressure and the outlet flow rate are measured. The pressure and outlet flow rate are controlled variables and the control valve stem positions on both sides are the manipulated variables. The variation in both inputs will influence both controlled variables. The control performance is good, in spite of varying valve coefficients of inlet and outlet.

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중학생들의 변인 통제 논리력과 변인 통제 유형 분석 (The Analysis of the Ability to Control Variables and the Types of Controlling Variables by Junior High School Students)

  • 이윤하;강순희
    • 한국과학교육학회지
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    • 제31권1호
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    • pp.32-47
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    • 2011
  • 본 연구에서는 학생들의 변인 통제 논리력과 변인 통제 활동을 분석하고자 하였다. 이를 위해 먼저 변인 통제 능력에 대한 구체적인 채점 기준을 개발하였다. 이어서, 중학교 2학년에 재학 중인 30명의 학생을 대상으로 학생들의 변인 통제 유형을 알아보았다. '계단 빨리 왕복하기'전략을 설계하도록 하는 과제를 부여한 후 얻어진 학생들의 응답 내용을 바탕으로 변인 통제 유형을 분석하였다. 변인 통제의 필요성 인식 여부, 불필요 변인의 배제 여부, 통제 변인의 설계 여부, 조작 변인과 종속 변인의 설계 여부의 네 가지 측면에 따라 유형A~유형F의 여섯 가지 유형으로 분류하였다. 그리고 Lawson의 과학적 사고 수준 검사 문항 중 변인 통제 논리에 해당하는 4개 문항에 대한 답변을 본 연구에서 개발한 채점 기준으로 채점하여 변인 통제 논리력을 측정하였다. Lawson이 개발한 과학적 사고 검사지로 측정한 점수와 변인 통제 논리력 점수의 상관 계수는 .67로 과학적 사고력와 변인 통제 논리력의 상관은 높은 것으로 나타났다(p<.01). 이는 본 연구에서 개발한 채점 기준이 학생들의 변인 통제 능력을 객관적으로 평가할 수 있다고 판단할 수 있으며, 또한 학생들의 과학적 사고력을 측정하는데 이용할 수 있음을 의미하는 것이다.

덕트 내부의 고차모드 수보다 적은 수의 제어음원과 마이크로폰을 이용한 덕트 방사소음 제어에 관한 연구 (A Study on Active Control of the Radiated Duct Noise with Insufficient Number of Control Dources and Microphones)

  • 윤두병;김양한;정균양;조대승
    • 소음진동
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    • 제8권2호
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    • pp.283-288
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    • 1998
  • If one wants to control the noise from a duct, then one must have sufficient number of sensors and actuators so that the control system is observable and controllable. A number of sensors and actuators for control of radiating noise from a duct have to be incorporated with the number of modes which one wants to control. These considerations motivated the present study that considers a control system which has less microphones and actuators than required. In this work, by theoretical analysis and numerical simulation, the control performance and robust reliability of such a kind of control system is investigated in terms of sound-field variables and control system variables. Then the possibility of implementation of the robust radiation power control system is verified by theoretical analysis and numerical simulation. In addition, the control performance of the control system is verified by experiment.

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Multivariate control charts based on regression-adjusted variables for covariance matrix

  • Kwon, Bumjun;Cho, Gyo-Young
    • Journal of the Korean Data and Information Science Society
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    • 제28권4호
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    • pp.937-945
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    • 2017
  • The purpose of using a control chart is to detect any change that occurs in the process. When control charts are used to monitor processes, we want to identify this changes as quickly as possible. Many problems in quality control involve a vector of observations of several characteristics rather than a single characteristic. Multivariate CUSUM or EWMA charts have been developed to address the problem of monitoring covariance matrix or the joint monitoring of mean vector and covariance matrix. However, control charts tend to work poorly when we use the highly correlatted variables. In order to overcome it, Hawkins (1991) proposed the use of regression adjustment variables. In this paper, to monitor covariance matrix, we investigate the performance of MEWMA-type control charts with and without the use of regression adjusted variables.

아동의 개인 및 가족변인과 교실의 심리사회적 환경변인이 자기통제에 미치는 영향 (The Individual, Family and Classroom Environmental Variables that Affect Children's Self-Control)

  • 이경님
    • 한국생활과학회지
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    • 제13권6호
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    • pp.833-845
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    • 2004
  • This study examines different individual and environmental factors that affect children's self-control. For an analysis, locus of control, perceived competence, and achievement motivation were all included in individual variables. For family variables, mothers' parenting and patents' marriage conflict were examined. For classroom psycho-social environment, teacher support, peer relationship, class involvement, and teachers' supervision were used. The sample consisted of 548 fifth and sixth grade children. Statistics and methods used for the data analysis were Cronbach's alpha, frequency, percentage, Pearson's correlation, and Hierarchical Regression. Several major results were found from the analysis: First, locus of control, perceived competence, and achievement motivation had a positive correlation with children's self-control. Second, mothers' affective parenting had a positive correlation with children's self-control. However, mothers' controlling parenting and parents' marriage conflict had a negative correlation with it. Third, teacher support, peer relationship, and class involvement had a positive correlation with children's self-control. In addition, teacher supervision had a positive correlation with girls' self-control. Fourth, class involvement, locus of control, and academic competence were important variables predicting boys' self-control. On the other hand, Class involvement, achievement motivation, academic competence, teacher's supervision, and mothers' controlling parenting were important variables predicting girl's self-control.

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변인 통제 능력을 강화하기 위한 수업 프로그램의 개발 및 적용 효과 분석 (The Development of a Learning Program for Enhancing the Skills of Control Variables and the Effects of Its Applications)

  • 이윤하;강순희
    • 대한화학회지
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    • 제55권3호
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    • pp.519-528
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    • 2011
  • 본 연구에서는 중학교 2학년을 대상으로 변인 통제 강화 프로그램을 개발하고, 이를 적용했을 때 과학적 사고력, 변인 통제 유형 변화에 미치는 효과를 알아보았다. 변인 통제 강화 모형은 변인 통제의 필요성을 인식하는 1단계, 학생들이 스스로 실험을 설계하여 진행하는 2단계, 자신들이 설계한 실험 과정을 되돌아보는 3단계로 구성된다. 이러한 모형에 기초하여 변인 통제 강화 프로그램을 개발하였다. 프로그램의 주제는 모두 9가지이며, 후반부로 갈수록 난이도가 높아진다. 프로그램을 적용한 결과, 학생들의 과학적 사고력 점수(로슨 SRT)는 다소 상승하였으나 통계적으로 유의미하지는 않았다. 사전에 실시한 변인 통제 유형 검사에서는 유형A~유형F까지 고루 분포하였는데 사후에는 변인 통제를 잘하는 유형인 유형A와 유형B가 많았다. 프로그램을 마친 후 실시한 설문을 분석한 결과, 학생들은 변인을 통제하는 실험을 하면서 과학적이고 비판적으로 생각해야 하는 점을 어렵고 힘들어했지만 자신감을 얻었음을 알 수 있었다.

상대이득행렬을 이용한 뉴로 퍼지 제어기의 설계 (Design of Neuro-Fuzzy Controller using Relative Gain Matrix)

  • 서삼준;김동식
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.157-157
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    • 2000
  • In the fuzzy control for the multi-variable system, it is difficult to obtain the fuzzy rule. Therefore, the parallel structure of the independent single input-single output fuzzy controller using a pairing between the input and output variable is applied to the multi-variable system. The concept of relative gain matrix is used to obtain the input-output pairs. However, among the input/output variables which are not paired the interactive effects should be taken into account. these mutual coupling of variables affect the control performance. Therefore, for the control system with a strong coupling property, the control performance is sometimes lowered. In this paper, the effect of mutual coupling of variables is considered by tile introduction of a simple compensator. This compensator adjusts the degree of coupling between variables using a neural network. In this proposed neuro-fuzzy controller, the Neural network which is realized by back-propagation algorithm, adjusts the mutual coupling weight between variables.

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