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EN
This paper presents a novel approach to the design of explainable recommender systems. It is based on the Wang–Mendel algorithm of fuzzy rule generation. A method for the learning and reduction of the fuzzy recommender is proposed along with feature encoding. Three criteria, including the Akaike information criterion, are used for evaluating an optimal balance between recommender accuracy and interpretability. Simulation results verify the effectiveness of the presented recommender system and illustrate its performance on the MovieLens 10M dataset.
EN
Open pit mining of rock minerals and the affected areas requiring further development are a serious challenge for shaping the positive image of the mining industry among the public. The direction and method of post-mining land reclamation are important for this image, which should take into account various factors describing the mining area, including social preferences. The article presents an example solution – fuzzy system (FSDR) – which supports the selection of the direction of reclamation of post-mining areas created after the termination of operations of open pit gravel and sand natural aggregate mines. The article presents selected factors determining the selection of the direction and possible reclamation variants as input and output data of the fuzzy system. The rules base of the developed system, as well as the mechanisms of inference and defuzzification, were also characterized. The application of the developed system is presented on selected examples.
PL
Eksploatacja surowców skalnych metodą odkrywkową oraz pozostające po niej tereny wymagające dalszego zagospodarowania stanowią poważne wyzwanie dla kształtowania pozytywnego wizerunku branży górniczej w odbiorze społecznym. Dla tego wizerunku istotnym jest przede wszystkim kierunek i sposób rekultywacji terenu poeksploatacyjnego, który powinien brać pod uwagę różne czynniki charakteryzujące teren pogórniczy, w tym preferencje społeczne. W artykule zaprezentowano przykład opracowanego rozwiązania – systemu rozmytego (FSDR) – który wspomaga wybór kierunku rekultywacji terenów pogórniczych powstałych po zakończeniu działalności kopalń odkrywkowych kruszyw naturalnych żwirowo – piaszczystych. W artykule przedstawiono wybrane czynniki determinujące wybór kierunku i możliwe warianty rekultywacji jako dane wejściowe i wyjściowe systemu rozmytego. Scharakteryzowano również bazę reguł opracowanego systemu oraz mechanizm wnioskowania i defuzyfikacji. Przedstawiono zastosowanie opracowanego systemu na wybranych przykładach.
PL
Artykuł opisuje implementację systemu rozmytego w mikrokontrolerze, dedykowanego dla instalacji centralnego ogrzewania. System ten dedykowany jest do automatyzacji pracy urządzeń instalacji w zależności od ustawień użytkownika. W tym celu dedykowana architektura kontrolera (sterownika) logiki rozmytej została opracowana. System ten, posiada 3 niezależne wejścia i 2 wyjścia; oraz wbudowane 3 wewnętrzne bloki fuzyfikacji, wnioskowania i wyostrzania.
EN
This paper describes an implementation of a fuzzy system in the microcontroller, dedicated for the central heating installation. This system is dedicated to automate work of devices of heating installation depending on user settings. For this purpose, a dedicated architecture of a fuzzy logic controller system was elaborated. This system has 3 independent inputs and 2 outputs and is composed of 3 internal blocks: fuzzification, inference and defuzzification.
EN
This paper presents a new approach in the field of trajectory tracking for nonholonomic mobile robot in presence of disturbances. The proposed control design is constructed by a kinematic controller, based on PD sliding surface using fuzzy sliding mode for the angular and linear velocities disturbances, in order to tend asymptotically the robot posture error to zero. Thereafter a dynamic controller is presented using as a sliding surface design, a fast terminal function (FTF) whose parameters are generated by a genetic algorithm in order to converge the velocity errors to zero in finite time and guarantee the asymptotic stability of the system using a Lyapunov candidate. The elaborated simulation works in the case of different trajectories confirm the robustness of the proposed approach.
EN
In this work we describe the optimization of a Fuzzy Logic Controller (FLC) for an autonomous mobile robot that needs to follow a desired path. The FLC is for the simulation of its trajectory, the parameters of the membership functions of the FLC had not been previously optimized. We consider in this work with the flower pollination algorithm (FPA) as a method for optimizing the FLC. For this reason, we use the FPA to find the best parameters with the objective of minimizing the error between the trajectory of the robot and the reference. A comparative study of results with different metaheuristics is also presented in this work.
EN
This paper deals with the fault diagnosis of wind turbines and investigates viable solutions to the problem of earlier fault detection and isolation. The design of the fault indicator, i.e., the fault estimate, involves data-driven approaches, as they can represent effective tools for coping with poor analytical knowledge of the system dynamics, together with noise and disturbances. In particular, the proposed data-driven solutions rely on fuzzy systems and neural networks that are used to describe the strongly nonlinear relationships between measurement and faults. The chosen architectures rely on nonlinear autoregressive models with exogenous input, as they can represent the dynamic evolution of the system along time. The developed fault diagnosis schemes are tested by means of a high-fidelity benchmark model that simulates the normal and the faulty behaviour of a wind turbine. The achieved performances are also compared with those of other model-based strategies from the related literature. Finally, a Monte-Carlo analysis validates the robustness and the reliability of the proposed solutions against typical parameter uncertainties and disturbances.
EN
This paper presents a novel approach to the design of fuzzy state feedback controllers for continuous-time non-linear systems with input saturation under persistent perturbations. It is assumed that all the states of the Takagi–Sugeno (TS) fuzzy model representing a non-linear system are measurable. Such controllers achieve bounded input bounded output (BIBO) stabilisation in closed loop based on the computation of inescapable ellipsoids. These ellipsoids are computed with linear matrix inequalities (LMIs) that guarantee stabilisation with input saturation and persistent perturbations. In particular, two kinds of inescapable ellipsoids are computed when solving a multiobjective optimization problem: the maximum volume inescapable ellipsoids contained inside the validity domain of the TS fuzzy model and the smallest inescapable ellipsoids which guarantee a minimum *-norm (upper bound of the 1-norm) of the perturbed system. For every initial point contained in the maximum volume ellipsoid, the closed loop will enter the minimum *-norm ellipsoid after a finite time, and it will remain inside afterwards. Consequently, the designed controllers have a large domain of validity and ensure a small value for the 1-norm of closed loop.
PL
W artykule przedstawiono sposób wprowadzenia funkcji progowej do modelu Relacyjnej Rozmytej Mapy Kognitywnej, wykorzystującego arytmetykę liczb rozmytych. Funkcyjne przetwarzanie liczby rozmytej powoduje deformacje kształtu liczby i jej nośnika. Zaproponowano „geometryczne” podejście do tego problemu, pozwalające zachować niezmienność nośnika oraz utrzymać kształt przetwarzanej liczby rozmytej przy jednoczesnym odpowiednim przesunięciu centrum tej liczby. Metoda została przetestowana na liczbach rozmytych o różnych funkcjach przynależności.
EN
The article describes the method for introducing a threshold function into a model of the Relational Fuzzy Cognitive Map that uses fuzzy numbers arithmetic. Processing the fuzzy number by function causes deformations of the shape if this number and its support. It is proposed a geometrical approach to this problem, allowing to maintain constancy of the support and to keep the shape of the processed fuzzy number with an appropriate shift of the center of this number. The method was tested on fuzzy numbers with different membership functions.
EN
Technique of creating a sub-line diagnostics status turbine unit thermal power plant based on an analysis of its diagnostic features. Rapid assessment of the technical state of turbine unit allows an early stage to detect the possibility of an emergency and to localize it. It involves the integration of the subsystems of the existing process control system (PCS), which will allow more efficient use of its information, hardware and software. Evaluation of the technical condition of the turbine unit thermal power plant is proposed to determine the use of modern intelligent technologies. The proposed method was used in the development of rapid diagnostic subsystems technical state of turbine of thermal power in Almaty.
PL
Zaproponowano metodykę opracowania podsystemu dynamicznej diagnostyki stanu turbogeneratora elektrowni cieplnej, która bazuje na analizie jego cech diagnostycznych. Dynamiczna ocena technicznego stanu turbogeneratora pozwala na wykrycie we wczesnym stadium awaryjnych sytuacji i jej lokalizacji. Proponuje się integrację tego podsystemu z istniejącym systemem automatycznego sterowania procesem technologicznym, co pozwoli bardziej efektywnie wykorzystać jego informacyjne, techniczne i programowe zabezpieczenia. Ocena technicznego stanu turbogeneratora elektrowni cieplnej proponuje się określić z wykorzystaniem współczesnych technologii inteligentnych. Zaproponowana metodyka była wykorzystana przy opracowaniu podsystemu diagnostyki dynamicznej stanu technicznego turbogeneratora w elektrowni cieplnej w Ałmaty.
EN
Concrete plays a vital role in the design and construction of the infrastructure. To meet the global demand of concrete in future, it is becoming a challenging task to find suitable alternatives to natural aggregates. Steel slag is a by-product of steel making process. The steel slag aggregates are characterized by studying particle size and shape, physical and chemical properties, and mechanical properties as per IS: 2386-1963. The characterization study reveals the better performance of steel slag aggregate over natural coarse aggregate. M30 grade of concrete is designed and natural coarse aggregate is completely replaced by steel slag aggregate. Packing density of aggregates affects the characteristics of concrete. The present paper proposes a fuzzy system for concrete mix proportioning which increases the packing density. The proposed fuzzy system have four sub fuzzy system to arrive compressive strength, water cement ratio, ideal grading curve and free water content for concrete mix proportioning. The results show, the concrete mix proportion of the given fuzzy model agrees with IS method. The comparison of results shows that both proposed fuzzy system and IS method, there is a remarkable increase in compressive strength and bulk density, with increment in the percentage replacement of steel slag.
PL
W pracy przedstawiono implementację modelu interfejsu użytkownika przeznaczonego do sterowania elektrycznym wózkiem inwalidzkim. W tym celu, dedykowana architektura sterownika systemu rozmytego została zaimplementowana w systemie Raspberry Pi. Głównym zadaniem sterownika systemu rozmytego jest generowanie wyjściowych sygnałów (lewo/prawo – l/p, przód/tył – p/t) sterujących pracą dwóch silników typu D.C. na podstawie sygnałów wejściowych, generowanych przez operatora; w tym celu opracowano wejściowe i wyjściowe zmienne lingwistyczne.
EN
This paper describes an implementation of a user interface model for guiding a wheelchair. For this purpose, a dedicated architecture of fuzzy logic controller was elaborated in Raspberry Pi system. The task of fuzzy logic controller is a generation of output signals (left/ right – l/r, front/back – f/b) steering two permanent magnet DC motors of the wheelchair based on input signals, created by the operator. Input and output linguistic variables and corresponding fuzzy sets were defined.
EN
Background: Project effectiveness is synonymous with project success. It is measured or assessed in terms of the degree to which project objectives are achieved. This paper presents an approach to evaluating the effectiveness of logistics projects. The starting point is the analysis of the current state of knowledge in the area of assessing project effectiveness, including logistics projects. The purpose of the study was to identify the critical factors determining the success of logistics projects and develop a model of logistics project effectiveness. Methods: The paper is based on the available recent scientific-theoretical research and publications and on practical studies in 25 enterprises seated in Poland. The study carried out by the authors had the form of questionnaires. The authors used a case study to validate the model of fuzzy decision-making system dedicated to estimate the level of logistics project effectiveness. Results: Based on a literature review and research findings, the authors propose the key success factors for logistics project effectiveness. In the paper the authors propose an approach to measure the level of logistics project effectiveness using their model based on fuzzy logic. This model laid the foundations for a fuzzy decision-making system in MATLAB environmental. The paper describes the implementation of the model via a case study. Conclusions: This approach allows for a more detailed description of logistics project effectiveness. The proposed model may be implemented by logisticians in an enterprise and/or supply chain. The approach can be useful to assess the level to which logistics project objectives are achieved - logistics project effectiveness.
PL
Wstęp: Efektywność projektu jest często utożsamiana z sukcesem projektu. Praca podejmuje zagadnienia związane z pomiarem i oceną skuteczności projektów, w tym przypadku projektów logistycznych. Autorzy dokonali analizy literatury tematu. Wyodrębnili kluczowe mierniki sukcesu projektów logistycznych. Na bazie przeprowadzonych badań zbudowano model skuteczności projektów logistycznych, który następnie zaimplementowano w systemie MATLAB. Metody: Praca została przygotowana w oparciu o dostępne badania zarówno teoretyczne, jak i praktyczne. Przeprowadzono badania ankietowe w 25 przedsiębiorstwach w Polsce. Wykorzystano studium przypadku celem ilustracji podjętego problemu. Rezultaty: Przygotowano zestaw mierników umożliwiających dokonanie oceny stopnia skuteczności realizacji celów projektów. Przygotowano model umożliwiający pomiar i ocenę skuteczności działań projektowych, który wykorzystuje logikę rozmytą. Opracowany model został zaimplementowany w systemie MATLAB. Wnioski: Proponowane podejście umożliwia opis problemu pomiaru i oceny skuteczności realizacji projektów logistycznych. Zaproponowane podejście może zostać wykorzystane przez logistyków, menedżerów projektów w ocenie skuteczności działań podejmowanych przez nich projektów logistycznych.
EN
For many practical weakly nonlinear systems we have their approximated linear model. Its parameters are known or can be determined by one of typical identification procedures. The model obtained using these methods well describes the main features of the system’s dynamics. However, usually it has a low accuracy, which can be a result of the omission of many secondary phenomena in its description. In this paper we propose a new approach to the modelling of weakly nonlinear dynamic systems. In this approach we assume that the model of the weakly nonlinear system is composed of two parts: a linear term and a separate nonlinear correction term. The elements of the correction term are described by fuzzy rules which are designed in such a way as to minimize the inaccuracy resulting from the use of an approximate linear model. This gives us very rich possibilities for exploring and interpreting the operation of the modelled system. An important advantage of the proposed approach is a set of new interpretability criteria of the knowledge represented by fuzzy rules. Taking them into account in the process of automatic model selection allows us to reach a compromise between the accuracy of modelling and the readability of fuzzy rules.
14
Content available remote Fuzzy-based computational simulations of brain functions - preliminary concept
EN
Research on the computational models of the brain constitutes an important part of the current challenges within computational neuroscience. The current results are not satisfying. Despite the continuous efforts of scientists and clinicians, it is hard to fully explain all the mechanisms of a brain function. Computational models of the brain based on fuzzy logic, including ordered fuzzy numbers, may constitute another breakthrough in the aforementioned area, offering a completing position to the current state of the art. The aim of this paper is to assess the extent to which possible opportunities concerning computational brain models based on fuzzy logic techniques may be exploited both in the area of theoretical and experimental computational neuroscience and in clinical applications, including our own concept. The proposed approach can open a family of novel methods for a more effective and (neuro)biologically reliable brain simulation based on fuzzy logic techniques useful in both basic sciences and applied sciences.
Logistyka
|
2015
|
nr 3
3743--3749, CD 1
PL
Modelowanie rozmyte jest powszechnie stosowane w wielu dziedzinach przemysłu. Jednym z zastosowań jest implementacja w sterowniku układu ABS. Modulowanie ciśnienia hydraulicznego w celu zabezpieczenia kół przed zablokowaniem się podczas hamowania jest wyjątkowo złożonym procesem. Na dynamikę hamowanego koła wpływają zarówno ciśnienie generowane przez pedał hamulca jak również rodzaj nawierzchni, chwilowy współczynnik tarcia opony o podłoże, warunki atmosferyczne oraz bezwładności. Proces ten jest wyjątkowo złożony, podlegający zakłóceniom o różnym typie i wartościach przez co stworzenie dokładnego modelu matematycznego jest praktycznie niemożliwe. Kontrola poślizgu hamowanych kół możliwa jest poprzez zastosowanie sterownika rozmytego, modulatorów ciśnienia oraz systemu kontrolno – pomiarowego. Autor przedstawia rozwiązanie sterownika rozmytego zastosowanego w lotniczym układzie ABS. W wyniku modelowania i symulacji otrzymano model regulatora rozmytego spełniającego stawiane wymagania.
EN
Fuzzy Logic provides a method to approach a control problem that focuses on what the system should do rather than modeling how it works. Fuzzy modeling is commonly used in many industry areas. One solution is the ABS system controller implementation. Modulating the hydraulic pressure in order to protect the wheels from blocking during braking is an extremely complex process. Braking wheel dynamics is affected by the hydraulic pressure generated by the brake pedal as well as surface type, friction coefficient between tire and the ground, weather conditions and inertias. Creating an accurate mathematical model of such interfered process is almost impossible. Wheel skid control can be performed by the Fuzzy Controller, pressure modulator, measuring and control system. The author presents the Fuzzy Logic solution used in the aviation ABS system. As a result of modeling and simulation the Fuzzy Controller model that meets all necessary requirements was obtained.
EN
In this work is presented a hybrid intelligent model of supervision based on Evolutionary Computation and Fuzzy Systems to improve the performance of the Oil Industry, which is used for Operational Diagnosis in petroleum wells based on the gas lift (GL) method. The model is composed by two parts: a Multilayer Fuzzy System to identify the operational scenarios in an oil well and a genetic algorithm to maximize the production of oil and minimize the flow of gas injection, based on the restrictions of the process and the operational cost of production. Additionally, the first layers of the Multilayer Fuzzy System have specific tasks: the detection of operational failures, and the identification of the rate of gas that the well requires for production. In this way, our hybrid intelligent model implements supervision and control tasks.
EN
This paper presents two innovative evolutionary-neural systems based on feed-forward and recurrent neural networks used for quantitative analysis. These systems have been applied for approximation of phenol concentration. Their performance was compared against the conventional methods of artificial intelligence (artificial neural networks, fuzzy logic and genetic algorithms). The proposed systems are a combination of data preprocessing methods, genetic algorithms and the Levenberg–Marquardt (LM) algorithm used for learning feed forward and recurrent neural networks. The initial weights and biases of neural networks chosen by the use of a genetic algorithm are then tuned with an LM algorithm. The evaluation is made on the basis of accuracy and complexity criteria. The main advantage of proposed systems is the elimination of random selection of the network weights and biases, resulting in increased efficiency of the systems.
EN
Fetal monitoring is based on analysis of fetal heart rate signal. Visual interpretation is difficult so computer-aided systems for quantitative analysis are commonly used. The clinical interpretation guidelines provided by FIGO (Fédération Internationale de Gynécologie et d'Obstétrique) were used to develop the weighted fuzzy scoring system for qualitative assessment of the fetal state. In this work, agreement of the fuzzy classification system with the neonatal outcome assessment was analyzed. Various datasets were evaluated, depending on interpretation method of the signals which were recorded from patients. The obtained results confirmed possibility of the efficient fetal state assessment using the fuzzy inference method proposed.
19
Content available remote Sterownik systemu rozmytego przeznaczony do sterowania silnikami DC
PL
W artykule przedstawiono implementację systemu rozmytego w układzie fpga Spartan3 przeznaczoną do sterowania silnikami prądu stałego. Przedstawiono wartości funkcji przynależności wejściowych oraz wyjściowych zmiennych lingwistycznych. W procesie wnioskowania wykorzystano metodę generowania adresu aktywnych reguł.
EN
In this paper present implementation of dedicated fuzzy system in fpga circuit Spartan3, which is used for steering of electric dc motors. In this paper also present values of input and output linguistic variables. In the proposed system a technique of addressing is applied, which is implemented in inference process. (Fuzzy logic controller dedicated for dc motors).
EN
In this paper the transient stability of power system is improved by development of an efficient generator tripping approach. Tripping number of generators is one of the most-used technique at when a serious disturbance lurching the steady sate operation of the power system. Traditional generator tripping techniques suffered from over-tripping generators beyond the stability requirements. The instability in the power system is usually followed by some delay to be detected by the system which has been unclear for traditional tripping approaches, resulting in misscommitment of tripping generators or unnecessary tripping. As a remedy to this, fuzzy system based rotor angle prediction is proposed to study the behavior of the fault before when the instability detected by the system. However, fuzzy system prediction has an impressive performance on nonlinear systems on which the rotor angle attitude is utterly an identical case with nonlinear characteristics. Results obtained by various and practical simulations exhibit that the stability index of the system improved by less number of tripped generators at the proper time. Simulations are conducted by MATLAB and DIgSILENT software on a 9- bus system with 3 generators to demonstrate the promised results.
PL
Przedstawiono metodę poprawy stanów przejściowych i stabilności system energetycznego przez ulepszenie wyzwalanie generatora. Dla poprawy jakości tego załączania zastosowano układ logiki rozmytej bazujący na przewidywaniu kąta wirnika.
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