Browsing by Subject "evolutionary algorithm"

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Algorytm ewolucyjny w optymalizacji uogólnionego zagadnienia plecakowego
(Data obrony: 2017-06-02) Zborowski, Kamil
Wydział Elektrotechniki, Automatyki, Informatyki i Inżynierii Biomedycznej
Access status: Open Access ,
Analysis of modification of the evolutionary algorithm for sequencing production tasks
(Wydawnictwa AGH, 2022) Ciepliński, Piotr; Golak, Sławomir; Wieczorek, Tadeusz
Evolutionary algorithms are one of the heuristic techniques used to solve task sequencing problems. An important example of such a problem is the issue of sequencing production tasks. The combinatorial optimization of task sequences allows the minimization of the cost or time of a set of production tasks by reducing the components of these values which are present in the transitions between tasks. This paper aims to analyze the influence of the production nature expressed by a set of production task parameters and a definition of the task transition cost on the effectiveness of the modification of the evolutionary algorithm based on new directed stochastic mutation operators. The research carried out included the influence of the space dimension of the task parameters, the number of levels of the value of the cost function, and a definition of this function. The results obtained allow us to assess the effectiveness of the directed mutation in task sequencing for productions of various natures.
Access status: Open Access ,
Configuring a hierarchical evolutionary strategy using exploratory landscape analysis
(2023) Guzowski, Hubert; Smołka, Maciej
Wydział Informatyki
Hierarchic Memetic Strategy (HMS) is a stochastic global optimizer designed to tackle highly multimodal problems. It consists of parallel running optimization methods organized in a tree hierarchy. Depending on the task, different algorithms can be utilized on each of the levels. In this paper, we incorporate into HMS's structure a mechanism for choosing its configuration based on information gathered by a set of Exploratory Landscape Analysis (ELA) methods and hyperparametric optimization. We compared the performance of such configured HMS with a portfolio of proven state-of-the-art algorithms on the suite of black-box optimization functions. The results of this work show the efficacy of HMS and provide a set of default parameters evaluated for algorithms users. The use of ELA methods to select the configuration of a composite algorithm extends their standard use as part of an algorithm selector and provides insight into the relationship between exploration and exploitation for different types of fitness functions.
Access status: Open Access ,
Enhancing a hierarchical evolutionary strategy using the Nearest-Better Clustering
(2024) Guzowski, Hubert; Smołka, Maciej; Pekař, Libor
Wydział Informatyki
A straightforward way of solving global optimization problems is to find all local optima of the objective function. Therefore, the ability of detecting multiple local optima is a key feature of a practically usable global optimization method. One of such methods is a multi-population evolutionary strategy called the Hierarchic Memetic Strategy (HMS). Although HMS has already proven its global optimization capabilities there is an area for improvement. In this paper we show such an enhancement resulting from the application of the Nearest-Better Clustering. Results of experiments consisting both of curated benchmarks and a real-world inverse problem show that on average the performance is indeed improved compared to the baseline HMS and remains on par with state-of-the-art evolutionary global optimization methods.
Access status: Open Access ,
Evolutionary approach for obtaining the hub and spoke structure in the logistic network
(AGH University of Science and Technology Press, 2011) Mażbic-Kulma, Barbara; Stańczak, Jarosław; Owsiński, Jan Wojciech; Sęp, Krzysztof
In order to describe transportation system, as a routine a connection graph would be used. Vertices of the graph can be train stations, bus stop, airports etc. The edges show direct connections between vertices. A direct application of such graph can be difficult and computational problems can occur while one would try to organize or optimize such a transportation system. Therefore, a method of aggregation of such graph was introduced, using the general kernel and shell structure and a hub and spoke transformation method of the source graph. These structures allow to concentrate and order the transport of goods/persons among vertices and enable to reduce the number of analyzed vertices as well as edges of the graph. In the presented paper we continue our work on kernel and shell and its instance hub and spoke methods of connection graph transformation. In this paper we develop model of the transportation system using the hub and spoke method with predetermined, minimum and indirectly described numbers of hub nodes. To obtain the desired structures, several versions of specialized evolutionary algorithm (EA) were developed and applied.
Access status: Open Access ,
Evolutionary approach to find kernel and shell structure of a connection graph
(AGH University of Science and Technology Press, 2009) Mażbic-Kulma, Barbara; Stańczak, Jarosław; Sęp, Krzysztof; Potrzebowski, Henryk
The theory of logistic transportation systems deals with models of phenomena connected with movement of goods and persons. The developed model of the transportation system is expected to simulate a real system, but also should help us to solve given transportation tasks. In order to describe transportation system (rail, bus or air), as a routine a connection graph would be used. Vertices of the graph can be train stations, bus stops etc.. The edges show direct connections between vertices. Its direct application can be difficult and computational problems can occur while one would try to organize or optimize such a transportation system. Therefore, a method of aggregation of such graph was introduced, using the general kernel and shell structure and its particular instances: hub-and-spoke and α-clique structured graphs of connections. These structures enable to concentrate and order the transport of goods/persons among vertices. To obtain these desired structures an evolutionary algorithm (EA) was applied. This method enables to reduce the number of analyzed vertices as well as arcs/edges of the graph.
Access status: Open Access ,
Finding structure kernel and shell with predetermined cardinality of kernel set, using evolutionary algorithm
(AGH University of Science and Technology Press, 2010) Mażbic-Kulma, Barbara; Stańczak, Jarosław; Sęp, Krzysztof
The theory of logistic transportation systems deals with models of phenomena connected with movement of goods and persons. The developed model of the transportation system is expected to simulate a real system, but also should help us to solve given transportation tasks. In order to describe transportation system (rail, bus or air), as a routine a connection graph would be used. Vertices of the graph can be train stations, bus stops etc. The edges show direct connections between vertices. Its direct application can be difficult and computational problems can occur while one would try to organize or optimize such a transportation system. Therefore, a method of aggregation of such graph was introduced, using the general kernel and shell structure and its particular instance the ?-clique structured graphs of connections. In the present approach, we use a predetermined number of communication hubs with the possibility of direct determining which nodes should become hubs or selecting them by the solving method. This structure allows to concentrate and order the transport of goods/persons among vertices and enables to reduce the number of analyzed vertices as well as arcs/edges of the graph. To obtain the desired structure, an evolutionary algorithm (EA) was applied.
Access status: Open Access ,
Knowledge-based modeling and multi-objective optimization of production in underground coal mines
(2013) Brzychczy, Edyta; Lipiński, Piotr
W artykule zaprezentowano nowoczesne podejście do modelowania i optymalizacji produkcji górniczej w wielozakładowym przedsiębiorstwie górniczym. W pierwszej części artykułu opisano charakterystykę procesu planowania prowadzonego w kopalniach węgla kamiennego. Następnie przedstawiono założenia dotyczące modelowania robót górniczych opartego na wiedzy. Zaproponowano wykorzystanie wiedzy w zakresie doboru sprzętu do warunków wyrobisk ścianowych oraz zestawiania maszyn i urządzeń ze sobą w zestawy ścianowe, pozyskanej w procesie Data Mining, do określenia możliwości wyposażenia planowanych wyrobisk ścianowych i ich wyników produkcyjnych. Etap optymalizacji realizowany jest przez specjalny algorytm ewolucyjny, umożliwiający wielokryterialną analizę i ocenę potencjalnych rozwiązań pod względem wybranych kryteriów, tj. minimalizację odchylenia wartości oczekiwanej wydobycia od wartości planowanych i minimalizację odchylenia standardowego wydobycia w analizowanym okresie w przypadku planowanych wyrobisk ścianowych. Sformułowany problem badawczy dotyczy optymalizacji produkcji górniczej dla d wyrobisk ścianowych i n zestawów ścianowych z uwzględnieniem istniejących ograniczeń. W opracowanym algorytmie MOEA-MPO analizie poddawana jest populacja N osobników reprezentujących potencjalne rozwiązania. Każdy osobnik reprezentowany jest przez wektor liczb całkowitych x o długości d, w którym każdy element wektora x/i odpowiada zestawom ścianowym przypisanym do danego wyrobiska ścianowego (x/i $\in$ {1, 2, ..., n}). W proponowanym algorytmie zastosowano trzy typy operatorów mutacji i operator krzyżowania. W artykule zaprezentowano główne elementy opracowanego algorytmu oraz przykładowe wyniki obliczeń.
Access status: Open Access ,
Optimization of simulation model parameters for solidification of metals with use of agent-based evolutionary algorithm
(Wydawnictwa AGH, 2008) Kluska-Nawarecka, Stanisława; Smolarek-Grzyb, Agnieszka; Byrski, Aleksander; Wilk-Kołodziejczyk, Dorota
The finite elements method (FEM) is currently widely used for simulation of thermal processes. However, one of still unresolved problems remains proper selection of mathematical model parameters for these processes. As far as modelling of cooling casts in forms is concerned, particular difficulties appear while estimating values of numerous coefficients such as: heat transport coefficient between metal and form, specific heat, metal and form heat conduction coefficient, metal and form density. Coefficients mentioned above depend not only on materials properties but also on temperature. In the paper the idea of optimalization of simulation method parameters based on adaptive adjustment of curve representing simulation result and result obtained in physical experiment is presented along with the idea of evolutionary and agent-based evolutionary optimization system designed to conduct such optimizations. Preliminary results obtained with use of ABAQUS system available in ACK CYFRONET and software developed at AGH-UST conclude the paper.
Access status: Restricted ,
Optymalizacja produkcji z zastosowaniem algorytmu ewolucyjnego
(Data obrony: 2017-01-17) Kowalczyk, Rafał
Wydział Elektrotechniki, Automatyki, Informatyki i Inżynierii Biomedycznej
Access status: Restricted ,
Optymalizacja przydziału zasobów za pomocą algorytmu ewolucyjnego
(Data obrony: 2017-01-23) Dębiński, Albert
Wydział Elektrotechniki, Automatyki, Informatyki i Inżynierii Biomedycznej
Access status: Restricted ,
Zastosowanie algorytmów ewolucyjnych w szczególnym zagadnieniu harmonogramowania
(Data obrony: 2017-01-19) Górnisiewicz, Roland
Wydział Elektrotechniki, Automatyki, Informatyki i Inżynierii Biomedycznej