• Title/Summary/Keyword: fuzzy boundary

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Endocardial boundary detection by fuzzy inference on echocardiography (퍼지 추론에 의한 심초음파 영상의 심내벽 윤곽선 검출)

  • 원철호;채승표;구성모;김명남;조진호
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.34S no.5
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    • pp.35-44
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    • 1997
  • In this paper, a an algorithm that detects the endocardial boundary, expanding the region from endocardial cavity using fuzzy inference, is proposed. This algorithm decides the ventricular cavity by fuzzy inference in process of searching each pixel from the inside of left ventricle in echocardial image and expands it. Uncertainty and fuzziness exists in decision of endocardial boundary. Therefore, we convert the lingustic representation of mean, standard deviation, and threshold value that are characteristic variables of endocardial boundary to fuzzy input and output variables. And, we extract proposed method is robuster to noise than radial searching method that is highly dependent on center position. To prove the similarity of detected boundary by fuzzy nference, we used the measures of SIZE, correlation coefficient, MSD, and RMSE and had acquired reasonable results.

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THIRD ORDER THREE POINT FUZZY BOUNDARY VALUE PROBLEM UNDER GENERALIZED DIFFERENTIABILITY

  • Prakash, P.;Uthirasamy, N.;Priya, G. Sudha
    • Journal of applied mathematics & informatics
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    • v.32 no.5_6
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    • pp.791-805
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    • 2014
  • In this article, we investigate third order three-point fuzzy boundary value problem to using a generalized differentiability concept. We present the new concept of solution of third order three-point fuzzy boundary value problem. Some illustrative examples are provided.

Fuzzy-based gaseous object segmentation on image plane (Fuzzy를 이용한 영상에서의 기체분리)

  • Kim, Won-Ha;Park, Min-Sik
    • Proceedings of the KIEE Conference
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    • 2001.11c
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    • pp.169-171
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    • 2001
  • Unlike rigid objects, the edge intensity of a gaseous object is various along the object boundary (edge intensities of some pixels on a gaseous object boundary are weaker than those of small rigid objects or noise itself). Therefore, the conventional edge detectors may not adequately detect boundary-like edge pixels for gaseous objects. In this paper A new methodology for segmenting gaseous object images is introduced. Proposed method consists of fuzzy-based boundary detector applicable to gaseous as well as rigid objects and concave region filling to recover object regions.

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A Computer Oriented Solution for the Fractional Boundary Value Problem with Fuzzy Parameters with Application to Singular Perturbed Problems

  • Asklany, Somia A.;Youssef, I.K.
    • International Journal of Computer Science & Network Security
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    • v.21 no.12
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    • pp.223-227
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    • 2021
  • A treatment based on the algebraic operations on fuzzy numbers is used to replace the fuzzy problem into an equivalent crisp one. The finite difference technique is used to replace the continuous boundary value problem (BVP) of arbitrary order 1<α≤2, with fuzzy boundary parameters into an equivalent crisp (algebraic or differential) system. Three numerical examples with different behaviors are considered to illustrate the treatment of the singular perturbed case with different fractional orders of the BVP (α=1.8, α=1.9) as well as the classical second order (α=2). The calculated fuzzy solutions are compared with the crisp solutions of the singular perturbed BVP using triangular membership function (r-cut representation in parametric form) for different values of the singular perturbed parameter (ε=0.8, ε=0.9, ε=1.0). Results are illustrated graphically for the different values of the included parameters.

THREE POINT BOUNDARY VALUE PROBLEMS FOR THIRD ORDER FUZZY DIFFERENTIAL EQUATIONS

  • Murty, M.S.N.;Kumar, G. Suresh
    • Journal of the Chungcheong Mathematical Society
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    • v.19 no.1
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    • pp.101-110
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    • 2006
  • In this paper, we develop existence and uniqueness criteria to certain class of three point boundary value problems associated with third order nonlinear fuzzy differential equations, with the help of Green's functions and contraction mapping principle.

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Fuzzy-Sliding Mode Control for Chattering Reduction (채터링 감소를 위한 퍼지 슬라이딩모드 제어)

  • Lee, Tae-Kyoung;Han, Jong-Kil;Ham, Woon-Chul
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.5
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    • pp.393-398
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    • 2001
  • This paper presents a new method with time-varying boundary layer and input gain, variated by Fuzzy Logic Control(FLC) by means of the system state in Sliding Mode Control (SMC). In addition to the time-varying boundary layer, the time-varying range of the fuzzy membership function has an effect on not only chattering reduction but also fast response characteristics. On the basis of SMC with time-varying boundary and FLC with time-varying input and output range, a computer simulation for inverted pendulum results in elimination of the chattering phenomenon and fast response.

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Predictive Spatial Data Fusion Using Fuzzy Object Representation and Integration: Application to Landslide Hazard Assessment

  • Park, No-Wook;Chi, Kwang-Hoon;Chung, Chang-Jo;Kwon, Byung-Doo
    • Korean Journal of Remote Sensing
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    • v.19 no.3
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    • pp.233-246
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    • 2003
  • This paper presents a methodology to account for the partial or gradual changes of environmental phenomena in categorical map information for the fusion/integration of multiple spatial data. The fuzzy set based spatial data fusion scheme is applied in order to account for the fuzziness of boundaries in categorical information showing the partial or gradual environmental impacts. The fuzziness or uncertainty of boundary is represented as two kinds of fuzzy membership functions based on fuzzy object concept and the effects of them are quantitatively evaluated with the help of a cross validation procedure. A case study for landslide hazard assessment demonstrates the better performance of this scheme as compared to traditional crisp boundary representation.

Fuzzy-Sliding Mode C.ontrol for Chattering Reduction (채터링 감소를 위한 퍼지 슬라이딩 모드 제어)

  • 이태경;문지운;함운철
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.72-72
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    • 2000
  • This paper presents a methodology combining sliding mode control and fuzzy control to tune the boundary layer and input gain according to the system state. The equivalent control is designed such that the nominal system exhibits desirable dynamics, The robust control with fuzzy self-tuning is then developed to guarantee the reaching condition and reduce chattering phenomenon in the presence of parameter and disturbance uncertainties.

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Error Reduction of Sliding Mode Control Using Sigmoid-Type Nonlinear Interpolation in the Boundary Layer

  • Kim, Yoo-Kyung;Jeon, Gi-Joon
    • International Journal of Control, Automation, and Systems
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    • v.2 no.4
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    • pp.523-529
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    • 2004
  • Sliding mode control with nonlinear interpolation in the boundary layer is proposed. A modified sigmoid function is used for nonlinear interpolation in the boundary layer and its parameter is tuned by a fuzzy controller. The fuzzy controller that takes both the sliding variable and a measure of chattering as its inputs tunes the parameter of the modified sigmoid function. Owing to the decreased thickness of the boundary layer and the tuned parameter, the proposed method has superior tracking performance than the conventional linear interpolation method.

Density based Fuzzy Support Vector Machines for multicategory Pattern Classification (밀도에 기반한 펴지 서포트 벡터 머신을 이용한 멀티 카데고리에서의 패턴 분류)

  • Park Jong-Hoon;Choi Byung-In;Rhee Frank Chung-Hoon
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2006.11a
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    • pp.251-254
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    • 2006
  • 본 논문은 multiclass 문제에서 기존에 나와 있는 fuzzy support vector mahchines 이 decision boundary 를 설정하는데 있어 모든 훈련 데이터에 대해서 바람직한 decision boundary 를 만들지 못하므로 그러한 경우를 예로 제시한다. 그리고 그에 대한 개선점으로 밀도를 이용해 decision boundary 를 조정하여 기존 FSVM 의 decision boundary 보다 더 타당한 decision boundary 를 설정하는 것을 보인다.

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