• Title/Summary/Keyword: Machine Theory

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A Study on the analogical analysis for the development and design of the electrical machine (전기기기개발과 설계를 위한 유추론적 해석에 관한 연구)

  • Lee, Gwon-Hyeon
    • Journal of the Korean Society for Precision Engineering
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    • v.6 no.2
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    • pp.47-57
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    • 1989
  • This paper aims at describing a series development of the electrical machine, by using the Similarity Theory. The character of the electrical machine defined as the Four Terminal Network of the electrical and mechanical energy transmission system, and the analogy theory of the modelmachine can be developed by the Four Termianl System. Also the Restriction Parameter and Disturbance Parameter can be founded by the comparative data of the developed machine that is the character of the theory and measurement.

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A Study on the Application of the Curvature Theory of Ruled Surfaces for the Development of Five-Axis NC Machine Real-Time Control Algorithm (5축 NC 기계의 실시간 제어기법 개발을 위한 룰드 서피스 곡률 이론의 적용 연구)

  • Kim, Jae-Hui;Yu, Beom-Sang
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.1 s.173
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    • pp.182-189
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    • 2000
  • This paper presents the real time control method of 5-axis NC machine for high precision and productivity based on the curvature theory, of a ruled surface. The trajectory, of NC machine is described by, way of a ruled surface generated by the points on part surface and tool axis direction vector. The curvature theory, of a ruled surface is then applied to deter-mine the motion parameters of the 5-axis machine for control. The controller computes position, orientation, and differential motion parameters of the tool in each sampling period. The real-time approach produces smoother surfaces and requires substantially less machining time compared to conventional off-line approaches. The propose real-time control method based of the curvature theory of a ruled surface may give new methodology of precision 5-axis machine control.

An Introduction of Machine Learning Theory to Business Decisions

  • Kim, Hyun-Soo
    • Journal of the Korean Operations Research and Management Science Society
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    • v.19 no.2
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    • pp.153-176
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    • 1994
  • In this paper we introduce machine learning theory to business domains for business decisions. First, we review machine learning in general. We give a new look on a previous framework, version space approach, and we introduce PAC (probably approximately correct) learning paradigm which has been developed recently. We illustrate major results of PAC learning with business examples. And then, we give a theoretical analysis is decision tree induction algorithms by the frame work of PAC learning. Finally, we will discuss implications of learning theory toi business domains.

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Distortion and Dilatatioin in the Tensie Failure of Paper

  • Park, Jong-Moon;James L. Thorpe
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.31 no.5
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    • pp.73-85
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    • 1999
  • Yield and fracture are separated in the tensile failure of paper. Failure in the machine direction of photocopy paper is contrasted with failure in the cross-machine direction . The ratios of distortion (shape change) to dilatation (volume change) for individual elements at yield and fracture are described. The ratios of distortion to dilatation are measured and compared to predicted values of the strain energy density theory. To evaluate the effect of the angle from the principal material direction on the strain energy density theory. To evaluate the effect of the angle from the principal material direction on the strain energy density factor, samples are prepared from machine direction to cross-machine direction in 15 degree intervals. the strain energy density of individual elements are obtained by the integration of stress from finite element analysis with elastic plus plastic strain energy density theory. Poison's ratio and the angle from the principal material direction have a great effect ion the ratio fo distortion to dilatation in paper. During the yield condition, distortion prevails over dilatation . At fracture, dilatation is at a maximum.

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A Study on the Expression of Scientism in Architectural Design of Rem Koolhaas (렘 콜하스 건축 디자인에서 과학주의의 표현에 관한 연구)

  • 김원갑
    • Korean Institute of Interior Design Journal
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    • v.13 no.2
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    • pp.80-90
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    • 2004
  • Scientism is a kind of paradigm since the birth of Modernism. Architectural design was also effected from scientism in the 1st Machine age, and being effected still In the End Machine age. But many architects in the 2nd Machine age express scientism in architectural design as a "science for kick" as SF. The design of Rem Koolhaas follows the line of Modernism which was effected from scientism in many ways. However he shows modified machine aesthetics as SF pataphysics mixed with literary imagination, and now shows new science paradigm in post-modern age. He expresses many new science theory like indeterminacy theory, chaos, catastrophe theory in his works. And those are expressed as indeterminate program that proceeds in non-linear way, rhizome in space, order out of chaos, topological metamorphosis as a catastrophe. This study analyzes the expression of scientism in architectural design of Rem Koolhaas since 1970s.nce 1970s.

A Study on the Pseudo-Scientifism in Architectural Design in the First Machine Age (제1기계시대 건축디자인에서의 유사과학주의에 관한 연구)

  • 김원갑
    • Korean Institute of Interior Design Journal
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    • no.26
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    • pp.49-56
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    • 2001
  • Science, technology and machine aesthetics were the main theme of architectural design in the first machine age. Modern architecture used the theory of science as its framework. But the theory of science was used not as a professional way, but as a pseudo-scientific way by modern architects. It was because that modern architects relied on the spiritual, mystical realm of science and mathematics. Moreover, the avant-garde movement in modernism used the theory of science and mathematics for its complicated and ailenated nature and scientific image. The pseudo-scientifism in architectural design in the first machine age was expressed mainly as a concentration on the 4th dimensional space and the use of symbolic image of science and technology.

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Application of data fusion and Dempster-Skater theory in fault diagnosis of induction motors (데이터 융합과 Dempster-Shafer 이론을 이용한 유도전동기의 결함진단)

  • Kim, Kwang-Jin;Han, Tian;Yang, Bo-Suk
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.11a
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    • pp.549-555
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    • 2003
  • The technology of machine condition monitoring is used effectively to detect the machine faults at an early stage using different machine quantities, such as current, voltage, temperature and vibration. Induction motors are most widely used to drive pumps, compressors and fans in industrial drives. This paper presents approach to data fusion using Dempster-Shafer theory because only one technique has uncertainty. So we can obtain advanced accuracy of the machine fault diagnosis. Vibration and current quantities are applied to diagnose three-phase induction motor.

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Purchase Prediction by Analyzing Users' Online Behaviors Using Machine Learning and Information Theory Approaches

  • Kim, Minsung;Im, Il;Han, Sangman
    • Asia pacific journal of information systems
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    • v.26 no.1
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    • pp.66-79
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    • 2016
  • The availability of detailed data on customers' online behaviors and advances in big data analysis techniques enable us to predict consumer behaviors. In the past, researchers have built purchase prediction models by analyzing clickstream data; however, these clickstream-based prediction models have had several limitations. In this study, we propose a new method for purchase prediction that combines information theory with machine learning techniques. Clickstreams from 5,000 panel members and data on their purchases of electronics, fashion, and cosmetics products were analyzed. Clickstreams were summarized using the 'entropy' concept from information theory, while 'random forests' method was applied to build prediction models. The results show that prediction accuracy of this new method ranges from 0.56 to 0.83, which is a significant improvement over values for clickstream-based prediction models presented in the past. The results indicate further that consumers' information search behaviors differ significantly across product categories.

A Study on the Construction of Dynamic Recursive Control Model through a Machine State Monitoring (기계상태 Monitoring을 통한 동적 Recursive 제어모형 구축에 관한 연구)

  • 윤상원;윤석환;신용백
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.17 no.30
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    • pp.107-116
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    • 1994
  • This paper formulates a dynamic monitoring and control model with a machine state by quality variations in a single lot production system. A monitoring model is based on estimate of machine state obtained using control theory. The model studied in this paper has a great advance from a point of view the combination between quality control (Sampling, Control Chart) and automatic control theory, and can be extended in a several ways.

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A Study on Safety Assessment and Design of the Safe Task in Automated Man-Machine System (자동생산체계에서 인간-기계 시스템의 안전도측정과 안전작업설계에 관한 연구)

  • 오영진
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.13 no.22
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    • pp.71-78
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    • 1990
  • Some problems to assess the safety of automated man-machine system are studied in many ways. The difficulty occurred in this system is the vagueness of human behavior. Fuzzy set theory is used to assess the human behavior in safety analysis. The unsafe behavior listed top 10 in accident statistics would be explained as the factors of human vagueness. Three cases are considered, which consist of man-machine system as man-man, man-machine, machine-machine types. For the design of safe task, using characteristics of work performance, each motion cycle time is required to know the rate of learning. Approach of human behavior to the standard motion means more safe motion. It is important to design the works as to minimize the time performance to the standard motion's, which utilize the control of risk potential with easy. In that process, use of fuzzy set theory is appropriate to analyze the human behavior to identify its vagueness.

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