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Found 5157 publications

Anisotropic vector hysteresis model applying Everett function and neural network

Amália Iványi Miklós Kuczmann

Publication Name: Physica B Condensed Matter

Publication Date: 2006-02-01

Volume: 372

Issue: 1-2

Page Range: 138-142

Description:

This paper deals with a simulation technique based on neural networks and an identification method to approximate the behavior of vector hysteresis characteristics of ferromagnetic materials. The identification procedure is based on theoretical measured vector Everett functions using Fourier expansion to deal with angle dependence of the measured scalar Everett functions and of the vector Everett functions in the 2D or in the 3D space. Computing afterwards the theoretical measured vector Everett functions for some given directions, the corresponding hysteresis models are approximated by neural networks and are used to build up the vectorial hysteresis model both in isotropic and anisotropic case. The properties of the anisotropic model has been analyzed and shown in figures. For some examples, the first order reversal curves determined from the vectorial model are compared with the corresponding measured curves that have been used to compute the measured scalar Everett functions being the input for the identification procedure. © 2005 Elsevier B.V. All rights reserved.

Open Access: Yes

DOI: 10.1016/j.physb.2005.10.034

Nonlinear simulation of a nondestructive testing measurement system

Amália Iványi Miklós Kuczmann

Publication Name: Physica B Condensed Matter

Publication Date: 2006-02-01

Volume: 372

Issue: 1-2

Page Range: 373-377

Description:

A nondestructive testing (NDT) equipment has been fabricated. The description of the measurement set-up with some measured crack signals applying a Hall-type sensor, furthermore, the T,Ψ-Ψ potential formulation of the nonlinear eddy current field problem in the time domain can be found in this paper. The hysteresis characteristic of the material has been simulated by the previously developed neural network (NN) based isotropic vector hysteresis model. The nonlinear system of equations has been solved by the fixed-point iteration scheme via the polarization method. Comparisons between the results of the 3D simulations and the measurements are also presented. © 2005 Elsevier B.V. All rights reserved.

Open Access: Yes

DOI: 10.1016/j.physb.2005.10.115

Non-associative fuzzy flip-flop with dual set-reset feature

No authors available

Publication Name: SISY 2006 - 4th Serbian-Hungarian Joint Symposium on Intelligent Systems

Publication Date: 2006-01-01

Volume:

Issue:

Page Range: 289-299

Description:

J-K flip-flops are the most general elementary units in sequential digital circuits. By extending Boolean operations to their respective fuzzy counterparts various fuzzy flipflops (F3) can be defined. Because of the axiomatic properties of fuzzy operations are considerably weaker then the properties satisfied by Boolean lattices, the minterm and maxterm type definitions of the same F3 are as a rule not equivalent. In former work we found a unique exception where simulation investigations lead to identical results for all parameter combinations examined. The base of this unique F3 is a pair of non-associative fuzzy connectives. In this paper the exact proof is given for the identity of the two definitions, i.e., for the uniqueness of the definition of this special non-associative F3.

Open Access: No

DOI: DOI not available

Non-associative fuzzy flip-flop with dual set-reset feature

Rita Lovassy L. T. Koczy

Publication Name: Sisy 2006 4th Serbian Hungarian Joint Symposium on Intelligent Systems

Publication Date: 2006-01-01

Volume: Unknown

Issue: Unknown

Page Range: 289-299

Description:

J-K flip-flops are the most general elementary units in sequential digital circuits. By extending Boolean operations to their respective fuzzy counterparts various fuzzy flipflops (F3) can be defined. Because of the axiomatic properties of fuzzy operations are considerably weaker then the properties satisfied by Boolean lattices, the minterm and maxterm type definitions of the same F3 are as a rule not equivalent. In former work we found a unique exception where simulation investigations lead to identical results for all parameter combinations examined. The base of this unique F3 is a pair of non-associative fuzzy connectives. In this paper the exact proof is given for the identity of the two definitions, i.e., for the uniqueness of the definition of this special non-associative F3.

Open Access: Yes

DOI: DOI not available

Expanded scope of traffic-flow analysis: Entity flow-phase analysis for rapid performance evaluation of enterprise process systems

No authors available

Publication Name: ESM 2006 - 2006 European Simulation and Modelling Conference: Modelling and Simulation 2006

Publication Date: 2006-01-01

Volume:

Issue:

Page Range: 94-98

Description:

This paper describes entity-flow phase analysis (EFA) which is a method for fast performance analysis of organisational process systems. EFA, similarly to traffic-flow analysis for communication systems (TFA), uses the combined approach of simulation and numerical methods. In simulation projects initiated to support the design of Information and Communication Technology (ICT) system and Business Process (BP) system in an organisation the parallel analysis of different systems may be efficient. EFA is a promising evaluation method to be applied for systems with determined BP and ICT subsystems in an organisational environment.

Open Access: No

DOI: DOI not available

Fuzziness and computational intelligence: Dealing with complexity and accuracy

L. T. Koczy

Publication Name: Soft Computing

Publication Date: 2006-01-01

Volume: 10

Issue: 2

Page Range: 178-184

Description:

No description provided

Open Access: Yes

DOI: 10.1007/s00500-005-0470-3

The effect of reduced bee pollination period to the fruit set of apricots

I. Skóla L. Szalay P. Benedek Z. Erdos J. Nyéki

Publication Name: Acta Horticulturae

Publication Date: 2006-01-01

Volume: 701 II

Issue: Unknown

Page Range: 723-726

Description:

The duration of effective bee pollination period was limited by caging flowering branches for shorter or longer time. In the case of self-fertile apricots even a partial limitation of the effective duration of bee pollination period significantly reduced the fruit set and the yield. This is because pollen dehiscence of anthers and the receptive period of stigmas do not overlap in time within the individual flowers. Accordingly, additional bee pollination (moving bee colonies to the orchards at blooming period) is needed to get a profitable yield when bee visitation of plantations is not abundant enough for some reasons.

Open Access: Yes

DOI: 10.17660/ActaHortic.2006.701.129

Classification of time series via wavelet subband analysis using support vector machine classifier

Balázs Benyó B. Paláncz

Publication Name: Periodica Polytechnica Electrical Engineering

Publication Date: 2006-01-01

Volume: 50

Issue: 1-2

Page Range: 129-140

Description:

An improved feature extraction method has been developed for classification and identification of time series, in case of the number of the experiments are considerably less than that of the samples in time series. The method based on the subband analysis of the wavelet transformation of the time signals, provides lower dimension feature vectors as well as much more robust kernel-based classifier than the traditional wavelet-based feature extraction method does. The application of this technique is illustrated by the classification of cerebral blood flow oscillation using support vector classifier with Gaussian kernel. The computations were carried out with Mathematica 5.1 and its Wavelet Application.

Open Access: Yes

DOI: DOI not available

Bacterial memetic algorithm for fuzzy rule base optimization

C. Cabrita J. Botzheim T. D. Gedeon Carlos Fonseca A. E. Ruano L. T. Koczy

Publication Name: 2006 World Automation Congress Wac 06

Publication Date: 2006-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In our previous works model identification methods were discussed. The bacterial evolutionary algorithm for extracting a fuzzy rule base from a training set was presented. The LevenbergMarquardt method was also proposed for determining membership functions in fuzzy systems. The combination of evolutionary and gradient-based learning techniques - the bacterial memetic algorithm - was also introduced. In this paper an improvement of the bacterial memetic algorithm is shown for fuzzy rule extraction. The new method can optimize not only the rules, but can also find the optimal size of the rule base. Copyright - World Automation Congress (WAC) 2006.

Open Access: Yes

DOI: 10.1109/WAC.2006.376057