• Title/Summary/Keyword: fuzzy logic reasoning

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Kinestatic Control using a Compliant Device by Fuzzy Logic (퍼지 논리에 의한 순응기구의 위치/힘 동시제어)

  • Seo, Jeong-Wook;Choi, Yong-Je
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.917-922
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    • 2004
  • As the tasks of robots become more diverse, some complicated tasks have come to require force and position hybrid control. A compliant device can be used to control force and position simultaneously by separating the twist of the robot's end effector from the twist of compliance and freedom by using stiffness mapping of the compliant device. The development of a fuzzy gain scheduling scheme of control for a robot with a compliant device is described in this paper. Fuzzy rules and reasoning are performed on-line to determine the gain of twists based on wrench error and twist error and twist of compliance and twist of freedom ratio. Simulation results demonstrate that better control performance can be achieved in comparison with constant gain control.

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A Fuzzy Logic Based Bin-Picking Technique (퍼지노리를 이용한 Bin-Picking방법)

  • 김태원;서일홍
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.41 no.8
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    • pp.938-946
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    • 1992
  • A novel 2-dimensional matched filter of the parallel-jaw type using fuzzy logic is proposed for bin picking. Specifically, the averaged pixel intensity of the windowed region for the filtering is considered to be fuzzy. Also membership functions for darkness and brightness are designed by employing the intensity histogram of the image. Then a rule is given to know how much a windowed region can be a possible holdsite. Furthermore eight rules are made to determine the part orientation, where Mamdani's reasoning method is applied. The proposed technique shows better performances than that of the conventional matched filtering technique in the following senses` 1) most of holdsites determined by the proposed technique are not concentrated at the locations nearly the end of part and 2) our filter is rather insensitive to noises than the conventional method. To show the validities of our proposed technique, some experimental results are illustrated and compared with the results by conventional matched filter technique.

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A Study on Trend Impact Analysis Based of Adaptive Neuro-Fuzzy Inference System

  • Yong-Gil Kim;Kang-Yeon Lee
    • International journal of advanced smart convergence
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    • v.12 no.1
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    • pp.199-207
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    • 2023
  • Trend Impact Analysis is a prominent hybrid method has been used in future studies with a modified surprise- free forecast. It considers experts' perceptions about how future events may change the surprise-free forecast. It is an advanced forecasting tool used in futures studies for identifying, understanding and analyzing the consequences of unprecedented events on future trends. In this paper, we propose an advanced mechanism to generate more justifiable estimates to the probability of occurrence of an unprecedented event as a function of time with different degrees of severity using adaptive neuro-fuzzy inference system (ANFIS). The key idea of the paper is to enhance the generic process of reasoning with fuzzy logic and neural network by adding the additional step of attributes simulation, as unprecedented events do not occur all of a sudden but rather their occurrence is affected by change in the values of a set of attributes. An ANFIS approach is used to identify the occurrence and severity of an event, depending on the values of its trigger attributes.

A Study on an Adaptive Membership Function for Fuzzy Inference System

  • Bang, Eun-Oh;Chae, Myong-Gi;Lee, Snag-Bae;Tack, Han-Ho;Kim, Il
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1998.10a
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    • pp.532-538
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    • 1998
  • In this paper, a new adaptive fuzzy inference method using neural network based fuzzy reasoning is proposed to make a fuzzy logic control system more adaptive and more effective. In most cases, the design of a fuzzy inference system rely on the method in which an expert or a skilled human operator would operate in that special domain. However, if he has not expert knowledge for any nonlinear environment, it is difficult to control in order to optimize. Thus, using the proposed adaptive structure for the fuzzy reasoning system can controled more adaptive and more effective in nonlinear environment for changing input membership functions and output membership functions. The proposed fuzzy inference algorithm is called adaptive neuro-fuzzy control(ANFC). ANFC can adapt a proper membership function for nonlinear plant, based upon a minimum number of rules and an initial approximate membership function. Nonlinear function approximation and rotary inverted pendulum control system ar employed to demonstrate the viability of the proposed ANFC.

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Context Aware System based on Bayesian Network driven Context Reasoning and Ontology Context Modeling

  • Ko, Kwang-Eun;Sim, Kwee-Bo
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.8 no.4
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    • pp.254-259
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    • 2008
  • Uncertainty of result of context awareness always exists in any context-awareness computing. This falling-off in accuracy of context awareness result is mostly caused by the imperfectness and incompleteness of sensed data, because of this reasons, we must improve the accuracy of context awareness. In this article, we propose a novel approach to model the uncertain context by using ontology and context reasoning method based on Bayesian Network. Our context aware processing is divided into two parts; context modeling and context reasoning. The context modeling is based on ontology for facilitating knowledge reuse and sharing. The ontology facilitates the share and reuse of information over similar domains of not only the logical knowledge but also the uncertain knowledge. Also the ontology can be used to structure learning for Bayesian network. The context reasoning is based on Bayesian Networks for probabilistic inference to solve the uncertain reasoning in context-aware processing problem in a flexible and adaptive situation.

Tunnel Lighting Control System using Fuzzy Reasoning (퍼지추론을 적용한 터널 조명제어시스템)

  • Lee, Jung-Eun;Choi, Hong-Kyoo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.8
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    • pp.1140-1145
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    • 2014
  • Tunnel lighting is composed of entrance zone, interior zone and exit zone by KS C 3703. We have to consider adaptation at entrance zone and exit zone lighting to prevent deteriorate visibility like black hole and white hole phenomenon. So External luminance, vehicle velocity and traffic volume should be considered in threshold zone lighting and vehicle speed and traffic volume should be considered in interior zone lighting. But existing tunnel lighting system is not good at visibility and economic because that is only controled by external luminance. So in this paper, We improve visibility and economic of tunnel lighting system using fuzzy reasoning according to external luminance, vehicle velocity, traffic volume.

A Hybrid Approach Using Case-Based Reasoning and Fuzzy Logic for Corporate Bond Rating (퍼지집합이론과 사례기반추론을 활용한 채권등급예측모형의 구축)

  • Kim Hyun-jung;Shin Kyung-shik
    • Journal of Intelligence and Information Systems
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    • v.10 no.2
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    • pp.91-109
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    • 2004
  • This study investigates the effectiveness of a hybrid approach using fuzzy sets that describe approximate phenomena of the real world. Compared to the other existing techniques, the approach handles inexact knowledge in common linguistic terms as human reasoning does it. Integration of fuzzy sets with case-based reasoning (CBR) is important in that it helps to develop a successful system far dealing with vague and incomplete knowledge which statistically uses membership value of fuzzy sets in CBR. The preliminary results show that the accuracy of the integrated fuzzy-CBR approach proposed for this study is higher that of conventional techniques. Our proposed approach is applied to corporate bond rating of Korean companies.

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A Study on Fuzzy Rule Functional Verification for Service ratio Prediction of Server in ATM Networks (ATM망에서 서버의 서비스율 예측을 위한 퍼지 규칙 기능 검증에 관한 연구)

  • 정동성;이용학
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.41 no.10
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    • pp.69-77
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    • 2004
  • In this thesis, we created a Fuzzy rule in a Fuzzy logic that are fuzzy logic which is composed of linguistic rules and Fuzzy inference engine for effective traffic control in ATM networks. The parameters of the Fuzzy rules are adapted to minimize the given performance index in both cases. In other words, the difuzzification value controls the service rate in the server to total traffic arrival ratio and buffer occupancy ratio using fuzzy set theory for traffic connected after reasoning. Also, show experiment result about rule by MATLAB6.5 and on-line bulid-up to verify validity of created Fuzzy rule. As a result, we can verify that service ratio in server is efficiently controlled by the total traffic arrival ratio and buffer occupancy ratio.

A Cascaded Fuzzy Inference System for University Non-Teaching Staff Performance Appraisal

  • Neogi, Amartya;Mondal, Abhoy Chand;Mandal, Soumitra Kumar
    • Journal of Information Processing Systems
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    • v.7 no.4
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    • pp.595-612
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    • 2011
  • Most organizations use performance appraisal system to evaluate the effectiveness and efficiency of their employees. In evaluating staff performance, performance appraisal usually involves awarding numerical values or linguistic labels to employees performance. These values and labels are used to represent each staff achievement by reasoning incorporated in the arithmetical or statistical methods. However, the staff performance appraisal may involve judgments which are based on imprecise data especially when a person (the superior) tries to interpret another person's (his/her subordinate) performance. Thus, the scores awarded by the appraiser are only approximations. From fuzzy logic perspective, the performance of the appraisee involves the measurement of his/her ability, competence and skills, which are actually fuzzy concepts that can be captured in fuzzy terms. Accordingly, fuzzy approach can be used to handle these imprecision and uncertainty information. Therefore, the performance appraisal system can be examined using Fuzzy Logic Approach, which is carried out in the study. The study utilized a Cascaded fuzzy inference system to generate the performance qualities of some University non-teaching staff that are based on specific performance appraisal criteria.

Fuzzy reasoning for assessing bulk tank milk quality (Bulk tank milk의 품질평가를 위한 퍼지기반 추론)

  • Kim Taioun;Jung Daeyou;Jayarao Bhushan M.
    • Journal of Intelligence and Information Systems
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    • v.10 no.3
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    • pp.39-57
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    • 2004
  • Many dairy producers periodically receive information about their bulk tank milk with reference to bulk tank somatic cell counts, standard plate counts, and preliminary incubation counts. This information, when collected over a period of time, in combination with bulk tank mastitis culture reports can become a significant knowledge base. Several guidelines have been proposed to interpret farm bulk tank milk bacterial counts. However many of the suggested interpretive criteria lack validation, and provide little insight to the interrelationship between different groups of bacteria found in bulk tank milk. Also the linguistic terms describing bulk tank milk quality or herd management status are rather vague or fuzzy such as excellent, good or unsatisfactory. The objective of this paper was to develop a set of fuzzy descriptors to evaluate bulk tank milk quality and herd's milking practice based on bulk tank milk microbiology test results. Thus, fuzzy logic based reasoning methodologies were developed based on fuzzy inference engine. Input parameters were bulk tank somatic cell counts, standard plate counts, preliminary incubation counts, laboratory pasteurization counts, non agalactiae-Streptococci and Streptococci like organisms, and Staphylococcus aureus. Based on the input data, bulk tank milk quality was classified as excellent, good, milk cooling problem, cleaning problem, environmental mastitis, or mixed with mastitis and cleaning problems. The results from fuzzy reasoning would provide a reference regarding a good management practice for milk producers, dairy health consultants, and veterinarians.

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