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EN
In the paper modified version of fan roulette selection method named proportional fan roulette selection is presented. This modification depends on increase of survive probability of the best individual at the expense of worse individuals and often gives better results compared to other selections. Test functions chosen from literature are used for determination of quality of proposed method. Results obtained using proportional fan roulette selection are compared with results obtained using roulette selection, elitist selection, and fan roulette selection.
PL
W artykule przedstawiono proporcjonalną selekcję wachlarzową będącą zmodyfikowaną wersją selekcji wachlarzowej. Wprowadzona modyfikacja polega na zwiększeniu prawdopodobieństwa przeżycia najlepszego osobnika kosztem osobników gorszych, często dając lepsze rezultaty w porównaniu do innych metod selekcji. Do sprawdzenia jakości utworzonej metody zastosowano funkcje testowe wybrane z literatury. Wyniki uzyskane przy użyciu proporcjonalnej selekcji wachlarzowej porównano z wynikami uzyskanymi przy użyciu selekcji ruletkowej, elitarnej oraz wachlarzowej.
PL
Praca przedstawia rezultaty zastosowania algorytmu genetycznego (AG) w problemie identyfikacji parametrów matematycznego modelu tłumika magneto-reologicznego (MR). Identyfikację parametrów prowadzono na podstawie badań eksperymentalnych. Przyjęty matematyczny model tłumika magneto-reologicznego opisywał zachodzące w nim zjawiska, na jego podstawie opracowano model numeryczny tłumika MR. Koncentrowano się na określeniu wpływu zastosowanej selekcji AG na dokładność i czas procesu identyfikacji. Rozważano następujące metody selekcji, tj.: równomierną, turniejową, ruletkę oraz stochastyczną równomierną.
EN
This paper presents the results of genetic algorithm (GA) application in the identification of mathematical model of a magneto-rheological damper parameters. Moreover, identification of model parameters is described and compared with results of direct experiment. Device model was developed as a rheological structure. Set of mathematical equations was used to describe the phenomena occurring in the MR damper. The results of research the influence of selection on process of searching the solution with the use of genetic algorithm were analyzed. One considered following methods of the selection: uniform, tournament, roulette and stochastic uniform. The analysis of selection methods with regard to convergence and accuracy for the process of searching solution and time of numerical calculations was carried out. The genetic algorithm has a stochastic character and so it doesn’t guarantee obtaining optimum solution, but it’s expected, that the best individual (with the least value of function, which was analyzed) will represent solution nearing the optimum one. Because of this character of GA every starting of identification process (runs) gives a bit different results and therefore in investigations usually the best result obtained from ten independent experiments or the average result is given.
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1991
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tom 37
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nr 1
EN
Each generation of Blattella germanica were treated with a dose of 0.42 μg permethrin per VI instar larva. The fecundity varied from 8.21 to 33.66 for I instar larvae per female. Reproduction was significantly lower than that evaluated for untreated insects in third and fourth generations, but significantly higher in the fifth generation. Mortality among insects treated with permethrin, with the exception of the fourth generation only, was higher than among untreated cockroaches. In the third; fourth and fifth generations, the biotic potential was significantly lower in groups of treated insects than in untreated ones. The length of the developmental period of B. germanica treated with permethrin, measured during 7 generations, showed no significant changes in comparison with the control groups.
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nr 2
29-43
EN
Most common approach to interpretation of genotype-environment interaction (GxE interaction) for breeding and variety recommendation purposes is stability and adaptation analysis of genotypes in a target region of cultivation. The aim of this paper was to review very rich both scientific and practical achievements in statistical methodology of stability and adaptation analysis of genotypes. The methods used could be divided into three groups: univariate parametric methods, univariate nonparametric methods and multivariate methods. Most of the methods are based on both fixed and mixed linear and multiplicative models. Stability measures defined in many models are useful to evaluating similarity of a genotype trait response to environmental conditions in a target region to a norm (concept) of dynamic (agronomic) stability which has been introduced by Becker and Leon (1988). Joint regression models belong to those most of ten used in considered studies. Recently, multivariate models and methods have become a standard statistical tool in interpreting GxE interaction for various purposes. They are extensions of the conventional joint regression models, both fixed and mixed ones. Among them, AMMI models and related methods have been most effective and, then of ten used in field experimentation. The AMMI models incorporate both additive and different kinds of multiplicative components. Some parametric and nonparametric criteria, incorporating both yield-means and yield-stability measures can be effective to selecting such genotypes which productivity in a target region indicates their wide adaptation.
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