• Title/Summary/Keyword: a fuzzy technique

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A Suggestion for Randomized Response Technique using Fuzzy Logic

  • Choi, Kyung-Ho
    • Communications for Statistical Applications and Methods
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    • v.8 no.2
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    • pp.465-471
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    • 2001
  • Randomized response technique is a survey technique for eliminating evasive answer bias. But this technique has a problem. This procedure suffers from linguistic expression in randomizing device. Thus for solving the problem, in this paper, we suggested the randomized response technique using fuzzy logic.

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Product image evaluation technique using fuzzy-weighted checklist (모호가중점검목록을 이용한 제품의 감성파악)

  • 박경수;정광태
    • Journal of the Ergonomics Society of Korea
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    • v.15 no.1
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    • pp.15-26
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    • 1996
  • When a product is designed, it is important to consider its image on consumers. In this study, we developed a technique to measure product image. Because human image of a product is very subjective and fuzzy, it is difficult to measure easily. To deal with this difficulty effectively, we used fuzzy- weighted checklist. The fuzzy-weighted checklist presents a fuzzy version of the weighted checklist technique for evaluating or comparing complex systems or subjects. In this technique, we used a pairwise comparison method to obtain the relative importance weights of image factors. Also, we used linguistic ratings to obtain the scores of image factors for a product. Then, we synthesized the scores of image factors to obtain a fuzzy composite score and its linguistic approximation. The entire procedure of this technique was written in quick Basic. As an example, this techinque is applied to car evaluation. The results show that this technique can be effectively used to the quqntitative evaluation of huamn image.

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Level control of single water tank systems using Fuzzy-PID technique

  • Lee, Yun-Hyung;Jin, Gang-Gyoo;So, Myung-Ok
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.5
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    • pp.550-556
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    • 2014
  • In this study, for the control of a single water tank system, a fuzzy-PID controller design technique based on a fuzzy model is investigated. For this purpose, a water tank system is linearized as a number of submodels depending on the operating point, and a fuzzy model is obtained by fuzzy combining. Each submodel is approximated as a first order time delay model, and a PID controller is designed using several existing tuning techniques. Then, through the fuzzy combination of this controller using the same method as that of the fuzzy model, a fuzzy-PID controller is designed. For the proposed technique, a simulation is performed using the fuzzy model of a water tank system, and the validity is examined by comparing its performance with that of a PID controller.

Stabilization Control of Ball and Beam System Using Adaptive Fuzzy Inference Technique (적응 펴지 추론기법을 이용한 Ball and Beam 시스템의 안정화 제어)

  • Kim, T.W.;Kim, H.B.;Shim, Y.J.;Shon, Y.D.;Lee, J.T.
    • Proceedings of the KIEE Conference
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    • 1997.07b
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    • pp.720-723
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    • 1997
  • The characteristics of ball and beam system using fuzzy inference technique can be described by fuzzy modeling. Therefore, this paper introduces a technique for fuzzy structure identification of nonlinear Input-output relation- ship using an adaptive fuzzy inference system. And the simulation result using adaptive fuzzy inference technique shows its effectiveness for fuzzy structure identification of nonlinear system.

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모호가중점검목록을 이용한 제품의 감성파악에 관한 연구

  • 박경수;정광태
    • Proceedings of the ESK Conference
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    • 1995.04a
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    • pp.25-29
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    • 1995
  • When we design a product, we need to consider human sensibility for the product. In this study, we developed a technique to measure human sensibility for a product. Because human sensibility for a product is very subjective and fuzzy, it is hard to measure easily. To deal with this difficulty effectively, we used fuzzy-weighted checklist to this problem. The fuzzy- weighted checklist presents a fuzzy version of the weighted checklist technique computerized for evaluating or comparing complex system (or subjects). In this technique, we used pairwise comparison to get the relative weights of wensibility factors. Also, we used linguistic ratings to get the scores of sensibility factors for a product. Then, we synthesize the scores of sensi- bility factors to get fuzzy composite score (and linguistic approximation). If there are several alternatives, we can conduct alternative comparison. Finally, we wrote the program of this technique by Quick Basic software. As an example, this technique applied to car. The results show that we can use this technique effectively to the quantitative evaluation of human sensibility

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A Fuzzy Technique-based Web Server Performance Improvement Using a Load Balancing Mechanism (퍼지기법에 기초한 로드분배 방식에 의한 웹서버 성능향상)

  • Park, Bum-Joo;Park, Kie-Jin;Kang, Myeong-Koo;Kim, Sung-Soo
    • Journal of KIISE:Computer Systems and Theory
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    • v.35 no.3
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    • pp.111-119
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    • 2008
  • This paper combines fuzzy concepts with an existing dynamic performance isolation technique in order to improve the response time performance of a Web server supporting differentiated services. A load balancing mechanism based on the fuzzy control technique is developed in such a way that ambiguous situations caused by workload estimation of cluster-based Web servers, client request rates, and dynamic request rates can be represented in an effective way. In addition, we verify that the fuzzy-based performance isolation technique improves the performance and robustness of differentiated service systems efficiently through comparing 95-percentile of response time between the fuzzy-based Performance isolation technique and the existing one, which do not use the fuzzy concept.

A Fuzzy Controller based on Fuzzy Relations (퍼지관계를 이용한 퍼지제어기의 설계)

  • Lee, Jihong;Moon, Jumsaeng
    • Journal of the Korean Institute of Intelligent Systems
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    • v.3 no.2
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    • pp.58-67
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    • 1993
  • Instead of Cartesian product in combining multiple input variables for fuzzy logic controllers, a fuzzy controller using fuzzy relations in inference procedure is proposed. Moreover, a technique is proposed by which conventional fuzzy control rules are transformed into the forms including fuzzy relations. It will be shown through several examples that the proposed technique gives smoother interpolation than conventional ones.

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Interactive Multiobjective Decision Making under Fuzzy Environment (Fuzzy 환경하에서의 상호작용적 다목적 의사결정)

  • 이상완;김재연
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.13 no.22
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    • pp.51-57
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    • 1990
  • A new interactive multiobjective decision making technique, which is called the fuzzy sequential proxy optimization technique, has been proposed. This technique is the revised version the sequential proxy optimization technique that the decision-maker's marginal rates of substitution is interpreted as type of L-R fuzzy numbers. It used to the square of normalized scalar product as the doptimalilry condition. However, this technique ignores the imprecise nature of a decision-maker's judgement of marginal rates of substitution. Also, it have a shortcoming that can be only applied over three objective functions. In this paper, considering the imprecise nature of a decision-maker's judgement, we presents an interactive fuzzy decision-making method on the basis of the decision-maker's MRS presented through the use of five types of membership functions including non-linear functions. FORTRAN programs that run in conversational mode are developed to implement man-machine interactive procedure.

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A Novel Neural Network Compensation Technique for PD-Like Fuzzy Controlled Robot Manipulators (PD 기반의 퍼지제어기로 제어된 로봇의 새로운 신경회로망 보상 제어 기술)

  • Song Deok-Hee;Jung Seul
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.6
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    • pp.524-529
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    • 2005
  • In this paper, a novel neural network compensation technique for PD like fuzzy controlled robot manipulators is presented. A standard PD-like fuzzy controller is designed and used as a main controller for controlling robot manipulators. A neural network controller is added to the reference trajectories to modify input error space so that the system is robust to any change in system parameter variations. It forms a neural-fuzzy control structure and used to compensate for nonlinear effects. The ultimate goal is same as that of the neuro-fuzzy control structure, but this proposed technique modifies the input error not the fuzzy rules. The proposed scheme is tested to control the position of the 3 degrees-of-freedom rotary robot manipulator. Performances are compared with that of other neural network control structure known as the feedback error learning structure that compensates at the control input level.

Group Decision Making Using Intuitionistic Hesitant Fuzzy Sets

  • Beg, Ismat;Rashid, Tabasam
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.14 no.3
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    • pp.181-187
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    • 2014
  • Dealing with uncertainty is always a challenging problem. Intuitionistic fuzzy sets was presented to manage situations in which experts have some membership and non-membership value to assess an alternative. Hesitant fuzzy sets was used to handle such situations in which experts hesitate between several possible membership values to assess an alternative. In this paper, the concept of intuitionistic hesitant fuzzy set is introduced to provide computational basis to manage the situations in which experts assess an alternative in possible membership values and non-membership values. Distance measure is defined between any two intuitionistic hesitant fuzzy elements. Fuzzy technique for order preference by similarity to ideal solution is developed for intuitionistic hesitant fuzzy set to solve multi-criteria decision making problem in group decision environment. An example is given to illustrate this technique.