• 제목/요약/키워드: Continuous function

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Time Dependent Correlation Function과 그의 응용에 관한 연구 (Some Study on Time Dependent Correlation Function and Its Applications)

  • 안수길
    • 대한전자공학회논문지
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    • 제10권6호
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    • pp.25-44
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    • 1973
  • 원인과 결과간의 위상과 work사이의 관계를 correlation function의 견지에서 검토하였고 continuous signal에 포함되어 있는 redundancy를 지적하여 sampling취급의 근거를 auto correlation면에서 보였다. 두 신호사이의 Correlation의 시간변동을 보여줄 수 있는 Time Dependent Correlation Function을 정의하여 PLL회로에서 그 유편성을 보였다. 끝으로 다상포낙선검파법에 의한 특성의 개선을 T.D.Correlation Furction에 의한 Correlation Analysis를 통하려 입증하였다.

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A continuous solution of the heat equation based on a fuzzy system

  • Moon, Byung-Soo;Hwang, In-Koo;Kwon, Kee-Choon
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제3권1호
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    • pp.13-17
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    • 2003
  • A continuous solution of the Dirichlet boundary value problem for the heat equation $u_t$$a2u_{xx}$ using a fuzzy system is described. We first apply the Crank-Nicolson method to obtain a discrete solution at the grid points for the heat equation. Then we find a continuous function to represent approximately the discrete values at the grid points in the form of a bicubic spline function (equation omitted) that can in turn be represented exactly by a fuzzy system. We show that the computed values at non-grid points using the bicubic spline function is much smaller than the ones obtained by linear interpolations of the values at the grid points. We also show that the fuzzy rule table in the fuzzy system representation of the bicubic spline function can be viewed as a gray scale image. Hence, the fuzzy rules provide a visual representation of the functions of two variables where the contours of different levels for the function are shown in different gray scale levels

의사결정나무와 손실함수를 이용한 공정파라미터 허용차 설계에 관한 연구 (A Study on the Design of Tolerance for Process Parameter using Decision Tree and Loss Function)

  • 김용준;정영배
    • 산업경영시스템학회지
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    • 제39권1호
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    • pp.123-129
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    • 2016
  • In the manufacturing industry fields, thousands of quality characteristics are measured in a day because the systems of process have been automated through the development of computer and improvement of techniques. Also, the process has been monitored in database in real time. Particularly, the data in the design step of the process have contributed to the product that customers have required through getting useful information from the data and reflecting them to the design of product. In this study, first, characteristics and variables affecting to them in the data of the design step of the process were analyzed by decision tree to find out the relation between explanatory and target variables. Second, the tolerance of continuous variables influencing on the target variable primarily was shown by the application of algorithm of decision tree, C4.5. Finally, the target variable, loss, was calculated by a loss function of Taguchi and analyzed. In this paper, the general method that the value of continuous explanatory variables has been used intactly not to be transformed to the discrete value and new method that the value of continuous explanatory variables was divided into 3 categories were compared. As a result, first, the tolerance obtained from the new method was more effective in decreasing the target variable, loss, than general method. In addition, the tolerance levels for the continuous explanatory variables to be chosen of the major variables were calculated. In further research, a systematic method using decision tree of data mining needs to be developed in order to categorize continuous variables under various scenarios of loss function.

ON THE DYNAMICAL PROPERTIES OF SOME FUNCTIONS

  • Yoo, Seung-Jae
    • 충청수학회지
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    • 제15권2호
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    • pp.47-56
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    • 2003
  • This note is concerned with some properties of fixed points and periodic points. First, we have constructed a generalized continuous function to give a proof for the fact that, as the reverse of the Sharkovsky theorem[16], for a given positive integer n, there exists a continuous function with a period-n point but no period-m points wherem is a predecessor of n in the Sharkovsky ordering. Also we show that the composition of two transcendental meromorphic functions, one of which has at least three poles, has infinitely many fixed points.

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NOTE ON THE EXPECTED VALUE OF A FUNCTION OF A FUZZY VARIABLE

  • Hong, Dug-Hun
    • Journal of applied mathematics & informatics
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    • 제27권3_4호
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    • pp.773-778
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    • 2009
  • Recently, Xue et al. [Computers and Mathematics with Applications 55 (2008) 1215-1224] proposed a formula for the expected value of a function of a fuzzy variable based on the assumption that the fuzzy variable has a continuous membership function. In conclusion, they remained the case where the membership function of the fuzzy variable is discontinuous for the future research, and then expected to get similar results. Thus this note is to propose a new formula for the expected value of a function of a general fuzzy variable which is not restricted on having a continuous membership function. Furthermore, we give an example which cannot be applied to the formula that Xue et al. proposed. We also use the same example given by Xue et al. to show how to apply the new formula.

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동적 기하 환경의 문제 해결 과정에서 연속 스펙트럼 활용에 대한 소고 (A study on the use of continuous spectrum in problem solving in a dynamic geometry environment)

  • 허남구
    • 한국수학교육학회지시리즈A:수학교육
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    • 제60권4호
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    • pp.543-554
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    • 2021
  • 동적 기하 환경은 학생들의 기하 문제 해결에 긍정적인 역할을 한다. 학생들은 드래깅을 통해 변화 속에서 불변성을 추측할 수 있으며, 분석법은 기하 문제를 해결하는 데 도움을 준다. 하지만 드래깅 활동과 분석법을 활용한 문제 해결은 제한점이 있으며, 연속 스펙트럼은 대안이 될 수 있다. 학생들은 코딩이 결합된 동적 기하 환경에서 프로그래밍을 통해 연속 스펙트럼을 구현할 수 있다. 이에 본 연구에서는 동적 기하 환경의 문제 해결에서 연속 스펙트럼을 활용하는 방안을 제시하였다. 학생들은 문제 해결의 이해 단계에서 시각적으로 표현된 문제 상황을 통해 즉각적으로 이해하고, 계획 단계에서 해결 전략을 수립하고, 반성 단계에서 결과의 점검 및 일반화하는 데 도움을 줄 수 있다.

학교수학과 학문수학에서의 연속성 개념 정의의 분석 (Analysis on Definitions of Continuity Conveyed by School Mathematics and Academic Mathematics)

  • 김진환;박교식
    • 대한수학교육학회지:수학교육학연구
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    • 제27권3호
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    • pp.375-389
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    • 2017
  • 본 연구에서는 연속성 개념에 대한 학교수학에서의 정의와 학문수학에서의 정의 사이의 차별성과 상호연결성을 네 가지 관점에서 분석하고 있다. 이에 따르면, '한 점에서의 연속 불연속'의 정의가 학교수학에서는 극한 과정에 의존하고 있고, 학문수학에서는 정의역의 위상에 의존하고 있다. 학교수학에서는 정의역이 하나의 구간이나 구간들의 합집합인 함수에 한하여 연속함수인가를 판정할 수 있으나, 학문수학에서는 어떠한 함수에 대해서도 연속함수인가를 판정할 수 있다. 본 연구에서는 이러한 결과에 근거하여, 학교수학에서의 연속성 개념 취급과 관련하여 다음 두 가지 의견을 제시한다. 첫째, 극한 과정을 기반으로 한 학교수학에서의 국소적 연속성 개념으로 볼 때, 2009 개정 교과서에서 함수의 정의역에 속하지 않는 특정한 점에서 불연속을 취급하는 것은 적절하다. 이때 불연속점으로 무한 불연속점, 제거 가능한 불연속점과 도약 불연속점의 유형이 나타난다. 둘째, 일반적인 연속함수의 정의로 "함수 y = f(x)에서 정의역에 불연속점이 없으면, f을 연속함수라 한다."를 제안한다. 이 정의는 정의역에 속하지 않은 점에서의 불연속성의 판정을 허용하면서, 학문수학에서의 정의와 일관되게 연결된다.

연속공정 자동화를 위한 Function block diagram형 제어언어의 설계 및 구현 (Design and Implementation of a Control Language for Continuous Process Automation : Function Block Diagram Approach)

  • 조영조;윤태웅;이준수;오상록;최익;김광배
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.226-231
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    • 1991
  • A graphic control language using function block diagram approach is designed and implemented, applicable to real-time control for continuous process automation system. The procedure implementing the control language is composed of three parts, editor, compiler, and executer. The editor generates the control algorithm file, which contains function block information in the text form, by menu-driven method on the color graphic screen. The compiler translates the contents of the control algorithm file to machine codes and their related data. Then, the executer generates a task that makes the machine codes executed at every sampling period in the target processor. The validity of the concept in its design and implementaion is assured by on-line simulation in the multi-function controller designed for continuous process automation.

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NONCOMMUTATIVE CONTINUOUS FUNCTIONS

  • Don, Hadwin;Llolsten, Kaonga;Ben, Mathes
    • 대한수학회지
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    • 제40권5호
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    • pp.789-830
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    • 2003
  • By forming completions of families of noncommutative polynomials, we define a notion of noncommutative continuous function and locally bounded Borel function that give a noncommutative analogue of the functional calculus for elements of commutative $C^{*}$-algebras and von Neumann algebras. These notions give a precise meaning to $C^{*}$-algebras defined by generator and relations and we show how they relate to many parts of operator and operator algebra theory.

Transformation of Mass Function and Joint Mass Function for Evidence Theory

  • Suh, Doug. Y.;Esogbue, Augustine O.
    • 한국지능시스템학회논문지
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    • 제1권2호
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    • pp.16-34
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    • 1991
  • It has been widely accepted that expert systems must reason from multiple sources of information that is to some degree evidential - uncertain, imprecise, and occasionally inaccurate - called evidential information. Evidence theory (Dempster/Shafet theory) provides one of the most general framework for representing evidential information compared to its alternatives such as Bayesian theory or fuzzy set theory. Many expert system applications require evidence to be specified in the continuous domain - such as time, distance, or sensor measurements. However, the existing evidence theory does not provide an effective approach for dealing with evidence about continuous variables. As an extension to Strat's pioneeiring work, this paper provides a new combination rule, a new method for mass function transffrmation, and a new method for rendering joint mass fuctions which are of great utility in evidence theory in the continuous domain.

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