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EN
The aging of composite insulators in outdoor operation for a long time has a direct impact on the safe and stable operation of the power grid. To solve this problem, fuzzy comprehensive evaluation of composite insulators based on level difference maximum is proposed. To verify the feasibility of this method, insulators in Xinjiang are sampled and the index evaluation system for composite insulators is established based on electrical, mechanical, hydrophobic and other properties, combined with operational years, geographical environment and other factors; Firstly, different membership functions are established according to index types. It is more likely to determine the grade of insulator by comparing measured data with the boundary value. Then, to solve the problem that weights cannot be effectively integrated in the combination weighting, level difference maximization is proposed (during the operation of insulators, the index which has a greater influence on the performance of insulators takes a higher proportion of the weight). Finally, on the basis of fully considering the clarity and ambiguity of grade division, the grade state of insulators is obtained by using the linear weighting method. The results show that compared with the traditional method, the improved method of the membership function and level difference maximum can realize the dynamic adjustment of the index based on the degree of information change. The method can better evaluate the insulator grade. The case study shows that the model can accurately and quickly judge the state of composite insulators, which can be used as a reference for manufacturing and maintenance departments.
EN
It has been shown that fuzzy integrals (Sugeno and Shocke) have special properties and are suitable for a fuzzy system for managing the resources of a telecommunication network. The form of choosing a method for calculating the Hurst coefficient in a fuzzy control system for telecommunication network resources is proposed.
PL
Wykazano, że całki rozmyte (Sugeno i Shock) mają szczególne właściwości i są odpowiednie dla systemu rozmytego do zarządzaniazasobami sieci telekomunikacyjnej. Zaproponowano formę wyboru metody obliczania współczynnika Hursta w systemie sterowania rozmytego dla zasobów sieci telekomunikacyjnych.
EN
In this paper, a new dynamic model was proposed for identifying the rock hardness during the process of roadway tunnelling, thereby regulating the speed of the driving motor and the torque of the cutting head. The presented identification model establishes a multi-information feature database containing vibration signals in the y-axis, acoustic emission signals, cutting current signals, and temperature signals. Subsequently, we obtain the membership functions (MFs) of the given multiple signals with the amount of feature samples according to the principle of minimum fuzzy entropy. Furthermore, a rock hardness identification model was established based on multi-sensor information fusion and Dempster-Shafer (D-S) evidence theory. To prove the accuracy of the proposed model, an identification experiment was carried out through the cutting of a poured mixed rock specimen with five grades of hardness. As a result, the proposed identification model recognizes the rock hardness accurately for fifteen sampling points, which indicates the significance of the method with regard to the dynamic identification of rock hardness during the process of roadway tunnelling, and further provides data support for adjusting the speed of the cutting head adaptively, thereby achieving high efficiency tunnelling.
EN
This research contribution instantiates a framework of a hybrid cascade neural network based on the application of a specific sort of neo-fuzzy elements and a new peculiar adaptive training rule. The main trait of the offered system is its competence to continue intensifying its cascades until the required accuracy is gained. A distinctive rapid training procedure is also covered for this case that offers the possibility to operate with non-stationary data streams in an attempt to provide online training of multiple parametric variables. A new training criterion is examined for handling non-stationary objects. Additionally, there is always an occasion to set up (increase) the inference order and the number of membership relations inside the extended neo-fuzzy neuron.
EN
Process of eye tomogram obtaining by means of optical coherent tomography is studied.Stages of idiopathic macula holes formation in the process of eye grounds diagnostics are considered. Main stages of retina pathology progression are determined: Fuzzy logic units for obtaining reliable conclusions regarding the result of diagnosis are developed. By the results of theoretical and practical research system and technique of retinal macular region of the eye state analysis.
PL
W artykule omówiono proces uzyskiwania tomogramu oka za pomocą optycznej tomografii koherentnej. Rozważane są etapy powstawania idiopatycznych plamek żółtych w procesie diagnostyki podstawy oka. Określono główne etapy progresji patologii siatkówki: opracowanie modeli logiki rozmytej, w celu uzyskania wiarygodnych wniosków dotyczących wyniku diagnozy. Na podstawie wyników badań teoretycznych i rezultatów uzyskanych z układu badawczego i techniki regionu plamki żółtej przeprowadzono analizy stanu oka.
EN
This paper presents a new method of identification of inertia moment of reduced masses on a shaft of an induction motor drive being a part of an electromechanical system. The study shows the results of simulations performed on the tested model of a complex electromechanical system during some changes of a backlash zone width. An analysis of wavelet scalograms of the examined signals carried out using a clustering technique was applied in the diagnostic algorithm. The correctness of the earliest fault detection has been verified during monitoring and identification of mass inertia moment for state variables describing physical quantities of a tested complex of the electromechanical system.
EN
Portfolio optimization, one of the most rapidly growing field of modern finance, is selection process, by which investor chooses the proportion of different securities and other assets to held. This paper studies the influence of membership function’s shape on the result of fuzzy portfolio optimization and focused on portfolio selection problem based on credibility measure. Four different shapes of the membership function are examined in the context of the most popular optimization problems: mean-variance, mean-semivariance, entropy minimization, value-at-risk minimization. The analysis takes into account both: the study of necessary and sufficient conditions for the existence of extremes, as well as the statistical inference about the differences based on simulation.
PL
W artykule przedstawiono konwencjonalne kryterium symetrii dla modelu przekształtnikowego układu napędowego. Sformułowano koncepcję oraz scharakteryzowano etapy strojenia regulatora rozmytego. Zaprezentowano uzyskane charakterystyki sterowania dla wybranych wyjściowych funkcji przynależności.
EN
The paper presents the conventional symmetry criterion for the model of the converter drive system. The concept of the fuzzy controller was formulated and the tuning stages were characterized. The obtained control characteristics for the selected output membership function were presented.
EN
The article dwells upon possibilities of the implementation of smooth calculation methods for predicting the demand for passenger transportation. The developed model which is based on fuzzy logic successfully solves the problem with traffic assignment – formation of passenger throughput for each traffic route. The model of correspondence takes into account such defining factors as fare on the route, average headway on it and fullness of the vehicle saloon. Different combination of these factors forms attractiveness as a criterion of an optimal route for a prospective passenger. It is determined that the lower saloon fullness, transportation fare and headway, the higher attractiveness is. Using the reasoned criterion, it is possible to allocate the total number of prospective passengers according to each existing route.
10
EN
The article presents the possibility of Rusing multi-criteria fuzzy analysis for assessing the region al competitiveness. This estimation can be used for place marketing strategy development and based on results of socio-economic development. The proposed approach is characterized by comparative estimation, when the level of development of one region is determined by the development of other areas. The final evaluation is the level of the cluster which the object being analyzed belongs. This allows ignoring minor fluctuations in Total indexes. The results of robust and fuzzy groups of regions are analyzed. This grouping is characterized by similar levels of development and helps to define the directions of further development of the regions.
EN
This paper gives the kinematic analysis of a 5-DOF industrial robotic manipulator while considering wrist in motion. Analytical solutions have been obtained for forward kinematics and inverse kinematics to accurately position the end-effector of robotic manipulator in three dimensional spaces. For the first time, a hybrid neuro-fuzzy intelligent technique with two different membership functions has been studied and their performances are comparatively evaluated with analytical solutions. An experiment has been performed for a desired trajectory. It is seen that the results for the intelligent technique are reasonably in agreement with experiment. Also, the results obtained highlight the importance of selection of a particular membership function for robotic manipulators of industrial use.
PL
W artykule przedstawiono analizę samochodów napędzanych silnikiem spalinowym oraz silnikiem elektrycznym ze względu na podstawowe parametry techniczne oraz skażenie środowiska. Ponieważ kryteria oceny pojazdów są zarówno kryteriami ilościowymi, jak i jakościowymi, posłużono się teorią zbiorów rozmytych. Na tej podstawie utworzono model rozmyty analizy porównawczej pojazdów.
EN
This paper presents an analysis of the internal combustion engine-powered vehicles and power because of the basic technical and environmental pollution. Since the criteria for assessing the vehicles are both quantitative criteria and qualitative, were used in the theory of fuzzy sets. On this basis, established a comparative analysis of fuzzy model vehicles.
PL
Przedstawiono algorytm umożliwiający znalezienie najkrótszej ścieżki w grafie. Dane opisujące krawędzie przedstawiono za pomocą trapezoidalnej funkcji przynależności. Do obliczeń zaproponowano wykorzystanie prostej defuzyfikacji wartości rozmytych do wartości ostrych.
EN
The paper presents an algorithm that allows finding the shortest path in the graph. Data describing the edges represented are by trapezoidal member-ship function. For the calculation proposed to use a simple defuzzification to the sharp values.
PL
Modelowanie podziału zadań przewozowych jest zagadnienie złożonym i wymaga dostępu do wyników badań ruchliwości prowadzonych w miastach i obszarach zurbanizowanych. W przypadku prowadzenia analiz dla obiektu hipotetycznego (a takim jest w wielu polskich miastach system Park and Ride), klasyczne metody zbierania danych nie znajdują zastosowania. W takim przypadku można zastosować procedurę wnioskowania rozmytego, której fundamentalnym elementem jest kształt funkcji przynależności. Dobór tego kształtu jest złożonym procesem i często wymaga arbitralnego przyjęcia funkcji przynależności. W ramach niniejszego artykułu proponuje się metodę bazującą na ankietach, w których o kształcie funkcji decydują eksperci zaznajomieni z problematyką. Proces ten jest wspomagany dwuetapowym ankietowaniem, wykorzystującym elementy techniki delfickiej. W artykule przedstawiono proces doboru kształtu funkcji przynależności na przykładzie modelowania podziału zadań przewozowych uwzględniającego podróże w systemie Park and Ride.
EN
Modal split modelling is very sophisticated task and requires access to mobility survey results. In the case of modelling of hypothetical object (Park and Ride demand in Polish conditions has such character), typical methods of data collection, i.e. household survey, are not suitable. In such case it is possible to apply fuzzy inference system, which is based on the shape of membership function. In the frame of the paper, it is proposed approach with expert survey, where shape of membership function is estimated by the transport experts, familiarized with multimodal split modelling. The process is supported by two stages inquiry, based on Delphic methodology. The paper presents whole process of membership function shaping, based on modal split modelling process, taking into consideration Park and Ride trips.
PL
W artykule przedstawiono koncepcję wykorzystania teorii zbiorów rozmytych L. A. Zadeha do wyznaczania ryzyka wieloczynnikowego w oparciu o lingwistyczną bazę wiedzy. Docelowy model rozmyty takiego systemu został skonstruowany według uogólnionego standardu sterownika rozmytego zaproponowanego przez E. H. Mamdaniego. We wstępie przedstawiono zarys teorii zbiorów rozmytych Zadeha oraz założenia aplikacyjne rozmytego sterownika Mamdaniego. W dalszej części został zaprezentowany przykładowy model systemu rozmytego służący do wyznaczania ryzyka wieloczynnikowego oparty na regułach logiki rozmytej i funkcjach lingwistycznych. Artykuł stanowi pionierską próbę wykorzystania formalnego aparatu teorii zbiorów rozmytych do wyznaczania ryzyka wieloczynnikowego rozpatrywanego na gruncie standardów bezpieczeństwa pracy.
EN
The article reveals the concept of using of L. A. Zadeh fuzzy sets theory in order to determine the multispectral risk taking into consideration the linguistic knowledge base. The target fuzzy model of such system was prepared following generalized main standard of the fuzzy controller developed by E. H. Mamdani. The introduction of following paper contains the broad outline of Zadeh fuzzy set theory as well as application idea of Mamdani fuzzy controllers. The following part introduces an example of the fuzzy system, which can be used to determine the multispectral risk basing on rules of fuzzy logic and linguistic functions. This pioneer work is an attempt to use formal apparatus of the fuzzy sets theory to determine the multispectral risk taking into consideration labor safety standards.
16
EN
Prediction of structural performance is a complex problem because of the existence of randomness and fuzziness in engineering practice. In this area, reliability analyses have been performed using probabilistic methods. This work investigates reliability analysis of structure involving fuzziness and randomness. In particular, the safety state of the structure is defined by a fuzzy state variable, fuzzy random allowable interval, or fuzzy random generalized strength. Because the membership function of the fuzzy safety state is the key to structural reliability analysis using the fuzzy sets theory, this work proposes useful methods to determine the membership functions and develops a structural reliability analysis method based on the fuzzy safety state. Several examples are provided to illustrate the proposed methods.
PL
Przewidywanie zachowania konstrukcji stanowi złożone zagadnienie ze względu na istnienie w praktyce inżynierskiej losowości i rozmytości. Na tym obszarze, analizy niezawodnościowe prowadzono dotąd przy pomocy metod probabilistycznych. W niniejszej pracy przedstawiono metodę niezawodnościowej analizy konstrukcji uwzględniającą rozmytość i losowość. Dokładniej, stan bezpieczeństwa konstrukcji określano za pomocą rozmytej zmiennej stanu, rozmytego losowego przedziału dozwolonego lub rozmytej losowej uogólnionej wytrzymałości. Ponieważ funkcja przynależności rozmytego stanu bezpieczeństwa stanowi klucz do niezawodnościowej analizy konstrukcji wykorzystującej teorię zbiorów rozmytych, w niniejszej pracy zaproponowano przydatne metody wyznaczania funkcji przynależności oraz opracowano metodę niezawodnościowej analizy konstrukcji opartą na rozmytym stanie bezpieczeństwa. Zaproponowane metody zilustrowano kilkoma przykładami.
PL
W pracy przedstawiono algorytm wyznaczania barwy rozmytej punktu barwnego (piksela) cyfrowego obrazu barwnego. Opracowano procedurę do wyznaczania pojedynczej składowej wektora barwy rozmytej (czyli wyznaczania stopnia przynależności punktu barwnego do jednego dowolnego obszaru trójkąta CIE). Następnie, korzystając z tej procedury pokazano, jak wyznaczyć wszystkie pozostałe składowe wektora barwy rozmytej. W tym celu rozpatrzono jeden obszar barwny trójkąta CIE ograniczony kilkoma krawędziami. Korzystając z dodatkowych funkcji pomocniczych pokazano, jak wyznaczyć funkcję przynależności w obszarze barwnym, a następnie stopień przynależności punktu barwnego do danego obszaru, tj. składową wektora barwy rozmytej tego punktu. Przedstawiony algorytm zastosowano w oprogramowaniu komory oceny barw z kamerą CCD.
EN
This paper presents the algorithm that calculates the fuzzy colour of a pixel in a digital coloured picture. The fuzzy colour is treated as the vector comprised of components that represent degrees of membership of the pixel to colour areas in the C.I.E. chromaticity triangle. In order to determine a single component of the vector of the fuzzy colour (i.e. to determine the degree of membership of a pixel to a given area of the C.I.E. triangle), a special procedure was developed. As shown in the paper, the procedure was subsequently used to determine all the remaining components. It was exemplified in the analysis of one colour area of the C.I.E. triangle bounded by several edges. The paper also presents how to determine the membership function in colour areas, and subsequently the degree of membership of a coloured point to a given colour area, i.e. a vector component of the fuzzy colour. The proposed algorithm was applied to the software for a colour assessment chamber with a CCD camera. It is in fact the key algorithm in all research on information processing which is based on fuzzy coloured areas of the C.I.E. chromaticity triangle.
18
Content available remote Estimation of accuracy for empirical assessment of membership function's value
EN
The membership function, being a fundamental measure in the fuzzy logic theory and the associated fuzzy numbers theory, is usually determined in technical applications as a'priori given crisp values i.e. mapping R-->R. Given the need for empirical determination of its value, there is a question of assessing the accuracy of the designation of its value. The authors propose the use of a modified formalism of fuzzy logic (sequential-binary approach YAAFL) and the empirical cumulative probability function for the Bernoulli distribution to determine confidence intervals for the membership function and to assess the type of probability distribution.
PL
Funkcja przynależności, będąca podstawową miarą w teorii logiki rozmytej i skojarzonej teorii liczb rozmytych, jest zazwyczaj w zastosowaniach technicznych określana a priori w formie ścisłej, tzn. odwzorowania R-->R. Ze względu na konieczność stosowania empirycznego wyznaczania jej wartości pojawia się zagadnienie oceny dokładności wyznaczenia jej wartości. Autorzy proponują wykorzystanie zmodyfikowanego formalizmu logiki rozmytej (podejście sekwencyjno-binarne YAAFL) oraz dystrybuanty empirycznej dla rozkładu Bernoulliego w celu wyznaczenia przedziałów ufności dla funkcji przynależności oraz oceny typu rozkładu.
PL
Układowe realizacje systemów wnioskowania przybliżonego wymagają często znacznych nakładów. Zmniejszenie ich jest możliwe poprzez zastosowanie metody dekompozycji Gupty i przedstawieniu systemu jako struktury hierarchicznej. W celu wyeliminowania jej niekorzystnych własności konieczny jest wstępny podział bazy wiedzy. Zaproponowana została metoda najlepszego wyboru wykorzystująca wybrane algorytmy podziału, zaimplementowana w sprzętowym systemie wnioskowania przybliżonego FPGA-FIS.
EN
The hardware cost of a fuzzy inference system can be reduced using the Gupta's relational decomposition technique [1]. The system can be represented as a hierarchical architecture that comprises a set of Single Input Single Output subsystems (Fig. 1). The decomposition has some disadvantages, computation of the global relation ℜ is an extremely time-consuming process and a large memory is necessary to store it. They can be eliminated if projection is expanded on linguistic level and decomposition is used for the knowledge base (1), (Fig. 2) [2]. The projection operation (on relational or linguistic level) in some cases can lead to inevitable loss of information because of its approximate nature [3]. To avoid the inference error (the output result is more fuzzy than that obtained in the classical system architecture (3)) methods for partitioning (5) the knowledge base KB[Y , XK,? , X1] into p subbases without inconsistent rules (4) are proposed [4]. In Section 3 the methods based on partitioning towards a defined input linguistic variable (Fig. 3) and elimination of the inconsistent rules (Fig. 4) are described [5, 6]. The algorithms are simple and fast but the results are not optimal in all cases (hardware cost depends on the number of subsystems p, Tab. 1). Thus, the method of the best choice is proposed and implemented in the FPGA fuzzy inference system as a DMU (Decomposition Management Unit) module (Fig. 6).
20
Content available remote Image segmentation based on fuzzy clustering with neighborhood information
EN
In this paper, an improved fuzzy c-means (IFCM) clustering algorithm for image segmentation is presented. The originality of this algorithm is based on the fact that the conventional FCM-based algorithm considers no spatial context information, which makes it sensitive to noise. The new algorithm is formulated by incorporating the spatial neighborhood information into the original FCM algorithm by a priori probability and initialized by a histogram based FCM algorithm. The probability in the algorithm that indicates the spatial influence of the neighboring pixels on the centre pixel plays a key role in this algorithm and can be automatically decided in the implementation of the algorithm by the fuzzy membership. To quantitatively evaluate and prove the performance of the proposed method, series of experiments and comparisons with many derivates of FCM algorithms are given in the paper. Experimental results show that the proposed method is effective and robust to noise. In this paper, an improved fuzzy c-means (IFCM) clustering algorithm for image segmentation is presented. The originality of this algorithm is based on the fact that the conventional FCM-based algorithm considers no spatial context information, which makes it sensitive to noise. The new algorithm is formulated by incorporating the spatial neighborhood information into the original FCM algorithm by a priori probability and initialized by a histogram based FCM algorithm. The probability in the algorithm that indicates the spatial influence of the neighboring pixels on the centre pixel plays a key role in this algorithm and can be automatically decided in the implementation of the algorithm by the fuzzy membership. To quantitatively evaluate and prove the performance of the proposed method, series of experiments and comparisons with many derivates of FCM algorithms are given in the paper. Experimental results show that the proposed method is effective and robust to noise.
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