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PL
Wykonany prototyp pozwala na symulację automatu komórkowego „Gry w Życie” Johna Conwaya oraz innych wariantów dwuwymiarowych automatów bazujących na liczbie żywych komórek w sąsiedztwie Moore’a. Urządzenie umożliwia wczytywanie podstawowych struktur z pamięci mikrokontrolera oraz dowolnych map z ustawieniami reguł symulacji z karty microSD. Struktury można edytować, tworzyć własne lub generować losowo. Sterowanie odbywa się pilotem na podczerwień, a symulacja jest wyświetlana poprzez przejściówkę VGA. Implementacja programu pozwala na symulację dwóch niezależnych automatów komórkowych jednocześnie, przełączanie istnienia ścian na krawędzi mapy oraz inne drugorzędne opcje.
EN
Cellular automata are capable of simulating complex structures with a short list of simple rules. Some of them can process computer operations inside the simulation and others are used in everyday life. Each cell’s state of the automaton can be calculated based on states of their surrounding cells at the same time for the next generation. The purpose of the following thesis was to analyze cellular automata and to create a prototype device using a selected microcontroller to simulate a cellular automaton and output its visual representation on a monitor through a VGA connector – that converts digital signal from the device to analog VGA signal to the monitor. The Arduino DUE development board was used to build the prototype. The device allows the user to simulate the structures of John Conway's "Game of Life" cellular automaton and others by modifying the simulation rules. Structures can be loaded from the program menu or from a microSD memory card. The device allows the user to simulate two independent cellular automata at the same time, pause and resume simulation with the option to increase or decrease the time between generations, turning walls on or off and modify cell states. The prototype is controlled by an infrared remote control.
EN
The transportation infrastructure is one of the most important resources for a country's economic and social well-being. The effectiveness of a country's street network will decide whether it develops further or stagnates. With the increasing number of vehicles on the road and the effects of urbanization, traffic roads are being subjected to a variety of requests and uses for which they were not designed, sized, or predicted. Because of the critical relevance of traffic roads, research must begin to lessen the effects of traffic jams in the streets, determine the appropriate number of traffic lanes, and integrate real-time traffic information into GPS systems. The goal of modeling a traffic-road system is to either build new traffic systems or gain a better knowledge of existing traffic systems so that they can be optimized. The accuracy, performance, stochastic and dynamic behavior of the model produced will be evaluated using a simulation of a genuine traffic system. This paper provides microscopic models based on cellular automation to replicate the behavior of various automobiles on a set of urban streets in Cluj Napoca city downtown. This model includes streets with multiple traffic lanes, various types of vehicles such as automobiles, buses, and trams, intersections with multiple possible upcoming streets controlled by traffic lights, bus stops inside and outside the traffic lane, tram stops inside the traffic lane, pedestrian crosswalks, and parking areas alongside and transversely with the right traffic lane of a street. TCA (Traffic Cellular Automata) is a proposed model that produces adequate findings in urban traffic theory. The results were obtained in both free-flow and traffic-jam conditions.
PL
Infrastruktura transportowa jest jednym z najważniejszych zasobów zapewniających dobrobyt gospodarczy i społeczny kraju. Skuteczność sieci ulic danego kraju zadecyduje o dalszym rozwoju lub stagnacji. Wraz z rosnącą liczbą pojazdów na drogach i skutkami urbanizacji, drogi drogowe są przedmiotem różnych wymagań i zastosowań, do których nie zostały zaprojektowane, zwymiarowane ani przewidziane. Ze względu na krytyczne znaczenie dróg, badania muszą zacząć łagodzić skutki korków na ulicach, określić odpowiednią liczbę pasów ruchu i zintegrować informacje o ruchu drogowym w czasie rzeczywistym z systemami GPS. Celem modelowania układu ruch-droga jest albo zbudowanie nowych układów ruchu, albo uzyskanie lepszej wiedzy o istniejących układach ruchu, aby można je było zoptymalizować. Dokładność, wydajność, zachowanie stochastyczne i dynamiczne wytworzonego modelu zostaną ocenione za pomocą symulacji rzeczywistego systemu ruchu. W tym artykule przedstawiono mikroskopowe modele oparte na automatyzacji komórkowej w celu odtworzenia zachowania różnych samochodów na zbiorze miejskich ulic w centrum miasta Cluj Napoca. Model ten obejmuje ulice z wieloma pasami ruchu, różnego rodzaju pojazdy, takie jak samochody, autobusy i tramwaje, skrzyżowania z wieloma możliwymi zbliżającymi się ulicami sterowanymi przez sygnalizację świetlną, przystanki autobusowe wewnątrz i poza pasem ruchu, tramwaje przystanki wewnątrz pasa ruchu, pieszy przejścia dla pieszych oraz parkingi wzdłuż i w poprzek z prawym pasem ruchu ulicy. TCA (Traffic Cellular Automata) to proponowany model, który daje odpowiednie wyniki w teorii ruchu miejskiego. Wyniki uzyskano zarówno w warunkach swobodnego przepływu, jak i w korku.
EN
Due to the importance of uranium and uranium alloys to national defence and nuclear industrial applications, it is necessary to understand dendrite formation in their solidification structures and to control their microstructures. In this study, a modified cellular automaton model was developed to predict 2-D and 3-D equiaxed dendrite growth in U-Nb alloys. The model takes into account solute diffusion, preferential growth orientation, interface curvature, etc., and the solid fraction increment is calculated using the local level rule method. Using this model, 2-D large-scale and 3-D equiaxed dendrite growth with various crystallographic orientations in the U-5.5Nb alloy were simulated, and the Nb micro-segregation behaviour during solidification was analysed. The simulated results showed reasonable agreement with the as-cast microstructure observed experimentally.
EN
Developing novel methods, approaches and computational techniques is essential for solving efficiently more and more demanding up-to-date engineering problems. Designing durable, light and eco-friendly structures starts at the conceptual stage, where new efficient design and optimization tools need to be implemented. Nowadays, apart from the traditional gradient-based methods applied to optimal structural and material design, innovative techniques based on versatile heuristic concepts, like for example Cellular Automata, are implemented. Cellular Automata are built to represent mechanical systems where the special local update rules are implemented to mimic the performance of complex systems. This paper presents a novel concept of flexible Cellular Automata rules and their implementation into topology optimization process. Despite a few decades of development, topology optimization still remains one of the most important research fields within the area of structural and material design. One can notice novel ideas and formulations as well as new fields of their implementation. What stimulates that progress is that the researcher community continuously works on innovative and efficient topology optimization methods and algorithms. The proposed algorithm combined with an efficient analysis system ANSYS offers a fast convergence of the topology generation process and allows obtaining well-defined final topologies.
5
Content available remote How to Synchronize Cellular Automata – Recent Developments –.
EN
The synchronization in cellular automata has been known as the firing squad synchronization problem (FSSP) since its development, in which it was originally proposed by Myhill and reported by Moore in 1964 to synchronize all/some parts of self-reproducing cellular automata. The problem has been studied extensively for more than fifty years, and a rich variety of synchronization algorithms has been proposed not only for one-dimensional (1D) arrays but also for multi-dimensional arrays. In the present paper, we construct a survey on the study of FSSP algorithms, focusing on recent developments.
PL
W pracy przedstawiono przykład rzeczywistej eksploatacji pokładowej węgla kamiennego kolejnych dwóch ścian w pokładzie 338/2. Eksploatacja spowodowała powstanie na powierzchni terenu górniczego niepełnej niecki obniżeniowej, która po wybraniu ściany nr 2 cechowała się znaczną asymetrią. Deformacje powierzchni objęte były systematycznymi pomiarami niwelacyjnymi wzdłuż linii pomiarowej „1”. Dla przedstawionego przykładu podziemnej eksploatacji wykonano obliczenia numeryczne z wykorzystaniem teorii automatów komórkowych. Zastosowano nieliniową funkcję przejścia. Wyniki obliczeń numerycznych porównano z w wynikami obserwacji geodezyjnych. Celem niniejszego artykułu jest weryfikacja założeń teoretycznych przyjętych dla przestrzennego modelu górotworu jako deterministyczny skończony automat komórkowy.
EN
The paper presents an example of real subsequent hard coal mining in the seam 338/2, which caused the formation of a subsidence trough on the surface of the mining area which after extraction of the longwall No. 2 was characterized by a significant asymmetry. Surface deformations were covered by systematic leveling measurements along the measurement line “1”. For the illustrated example of underground mining, numerical calculations were made using the theory of cellular automata. A non-linear transition function was used. Calculated data were compared with the results of geodetic observations. The aim of the article was to verify the theoretical assumptions of the model and to demonstrate the practical possibilities of applying the method to assess the subsidence of the mining area.
PL
W pracy przedstawiono rozwinięcie koncepcji budowy płaskiego modelu górotworu zbudowanego w oparciu o teorię automatów komórkowych. Pokazana została możliwość odwzorowania dyslokacji tektonicznych. Odwzorowanie szczeliny uskokowej odbywa się na zasadzie podobieństwa geometrycznego. Jej oddziaływanie na rozkład deformacji w modelu zależne jest od szeregu czynników. M.in. od głębokości eksploatacji, nachylenia szczeliny uskokowej oraz grubości nadkładu. Wpływ wymienionych czynników został przedstawiony na przykładach abstrakcyjnej eksploatacji górniczej.
EN
This paper presents the evolution of the concept of development of the 2-dimensional rock mass model based on the theory of cellular automata. The possibility of mapping tectonic dislocations has been shown. The projection of the fault gap is based on geometric similarity. Its influence on the deformation distribution in the model depends on a number of factors, among others, the depth of exploitation, the slope of the fault gap and the thickness of the overburden. The influence of these factors has been presented based on examples of abstract mining exploitation.
EN
A Brownian cellular automaton (BCA) is an asynchronous cellular automaton (ACA) in which local configurations representing signals may move forth and back randomly, as if they were undergoing random walks. The random fluctuation offers a natural mechanism to propagate signals in the 2-dimensional cell space, and to cross signals moving in directions perpendicular to each other. As a result, the BCA in (Lee et al., 2016) employs 4 cell states and 17 transition rules to conduct universal computation, both of which are less than other equivalent ACAs in the literature. This paper aims to advance the fluctuation-based scheme one step further, via proposing a new BCA with 4 states and 14 rules that achieves a reduction in the number of transition rules. We show that the BCA is capable of implementing any arbitrary logic circuit, thereby proving its universality in computation. We illustrate this by implementing a circuit that converts a 4-bit number to its equivalent hexadecimal digit.
EN
What is the limit of improvement the structure obtained directly from the liquid state, with possible heat treatment (supersaturation and aging)? This question was posed by casting engineers who put arbitrary requirements on reducing the DAS (Dendrite Arm Spacing) length to less than a dozen microns. The results of tests related to modification of the surface microstructure of AlSi7Mg alloy casting treated by laser beam and the rapid remelting and solidification of the superficial casting zone, were presented in the paper. The local properties of the surface treated with a laser beam concerns only a thickness ranging from a fraction to a single mm. These local properties should be considered in the aspect of application on surfaces of non-machined castings. Then the excellent surface layer properties can be used. The tests were carried out on the surface of the casting, the surface layer obtained in contact with the metal mould, after the initial machining (several mm), was treated by the laser beam. It turned out that the refinement of the microstructure measured with the DAS value is not available in a different way, i.e. directly by casting. The experimental-simulation validation using the Calcosoft CAFE (Cellular Automaton Finite Element) code was applied.
PL
W pracy przedstawiono przykład rzeczywistej eksploatacji pokładowej węgla kamiennego kolejnych dwóch ścian. Eksploatacja spowodowała powstanie na powierzchni terenu górniczego niepełnej niecki obniżeniowej. Deformacje powierzchni objęte były systematycznymi pomiarami niwelacyjnymi wzdłuż linii pomiarowej „1”. Dla przedstawionego przykładu podziemnej eksploatacji wykonano obliczenia numeryczne z wykorzystaniem teorii automatów komórkowych a następnie porównano je w wynikami obserwacji geodezyjnych. Celem niniejszego artykułu jest weryfikacja założeń teoretycznych przyjętych dla przestrzennego modelu górotworu jako deterministycznego skończonego automatu komórkowego.
EN
The paper presents an example of real subsequent hard coal mining, which caused the formation of a subsidence trough on the surface of the mining area. Surface deformations were covered by systematic leveling measurements along the measurement line “1”. For the illustrated example of underground mining, numerical calculations were made using the theory of cellular automata. Calculated data were compared with the results of geodetic observations. The aim of the article was to verify the theoretical assumptions of the model and to demonstrate the practical possibilities of applying the method to assess the subsidence of the mining area.
11
Content available remote Friction Stir Radial Backward Extrusion (FSRBE) as a new grain refining technique
EN
A new method entitled Friction Stir Radial Backward Extrusion (FSRBE) is presented for processing fine-grained tubes. In FSRBE technique, an initial pure copper billet is placed inside a cylindrical chamber. The billet is pushed toward a rotating tool which results in radial and backward flow of the material while is frictionally stirred. The microstructure evolution during FSRBE was investigated through experimental observations and cellular automaton (CA) modeling. The observations reveal that the microstructure with initial grain size of 75 μm was refined to a fine-grained structure with an average grain size of 12 μm. The results of tensile tests demonstrate slight improvement in the value of yield and ultimate strength, elongation and microhardness. The microstructural evolution during FSRBE processing in the micro-level was studied using a coupled cellular automaton algorithm and finite element model. First, the macroscopic plastic flow behavior of material during FSRBE was calculated using FEM simulation method. Next, by tracing the plastic strain, the strain rate and temperature, in the deformation domain of cellular automaton, the DRX kinetics of pure copper is obtained in a devised post-processing step. The microstructure observations showed that the proposed model predictions were in reasonably good agreement with the experimentally obtained results.
12
Content available remote Computer modelling of ductile iron solidification using FDM and CA methods
EN
Purpose: The purpose of the work was the presentation of tool for modelling of solidification process, for prediction of some structure parameters in DI by the given chemical composition of alloy and for given boundary condition of casting. Design/methodology/approach: Two mathematical models and methods developed by authors have been presented: micromodelling with using of finite difference method (FDM) and mesomodelling with using of cellular automaton method (CA). Findings: The FDM was used for solving the DI solidification model, including heat conductivity equation with source function, boundary condition for casting, equations for austenite and eutectic grains nucleation depended on the changing undercooling, the Weibull’s formula for graphite nodule count, Kolmogorov’s equation for calculation of volume fraction of phases (eutectics and austenite). A set of equations, after transformation to a difference form, were solved by the finite difference method, using an iteration procedure. The correctness of the mathematical model has been experimentally verified in the range of most significant factors, which include temperature field, the value of maximum undercooling, and the graphite nodule count interrelated with the casting cross-section. Literature offers practically no data on so confronted process model and simulation program. The CA model was used for the simulation of the grains’ shapes in connection with FD for temperature field and solute redistribution in the grain scale. Practical implications: FDM modeling gives the possibility of statistical description of microstructure but the geometrical shape of grains is assumed a priori. In CA modeling the grain shape is not assumed, but this is the result of modeling. The use of FDM gives results quantitatively comparable to the process in real casting, particularly according to temperature fields and number of graphite spheroids. Originality/value: The CA method gives on the present stage credible qualitative results but this method is more perspective for good reproducing of the real process of solidification.
13
Content available remote Multiphysics and multiscale modelling of ductile cast iron solidification
EN
The presented model of ductile cast iron solidification is a typical sample of multiphysics and multiscale engineering system. This model takes into consideration the different time and spatial scales of accounted phenomenon of microstructure formation: heat diffusion, components mass diffusion in the liquid and solid phases, thermodynamic of phase transformation under the condition of inhomogeneous chemical composition of growing and vanishing phases, phase interface kinetics and grains nucleation. The results of two-dimensional modelling of the microstructure formation in the ductile cast iron (so called - Ductile Iron - DI) are presented. The cellular automaton model (CA) was used for the simulation. Six states of CA cells were adopted to three phases above mentioned (liquid, austenite and graphite) and to three two-phase interfaces. For the modelling of concentration and temperature fields the numerical solution was used. The parabolic nonlinear differential equations with a source term were solved by using the finite difference method and explicit scheme. The overlapping lattices with the same spatial step were used for the concentration field modelling and for the CA. The time scale of the temperature field for this lattice is about 104 times shorter. Due to above reasons the another lattice was used with a multiple spatial step and the same time step.
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