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Využití imsetů při učení bayesovských sítí
Vomlel, Jiří ; Studený, Milan
This paper describes a modification of the greedy equivalence search (GES) algorithm. The presented modification is based on the algebraic approach to learning. The states of the search space are standard imsets. Each standard imset represents an equivalence class of Bayesian networks. For a given quality criterion the database is represented by the respective data imset. This allows a very simple update of a given quality criterion since the moves between states are represented by differential imsets. We exploit a direct characterization of lower and upper inclusion neighborhood, which allows an efficient search for the best structure in the inclusion neighborhood. The algorithm was implemented in R and is freely available.
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Evolutionary Optimization of Control Algorithms
Weisser, Roman ; Šeda, Miloš (referee) ; Zelinka,, Ivan (referee) ; Ošmera, Pavel (advisor)
The dissertation thesis deals with Evolution optimization of control algorithms. The first part of the thesis describes the principles and partial methods of evolution optimization methods especially those used in two-level transplant evolution method. Later the grammatical evolution method is described, which modified algorithm became impulse for creation of transplant evolution method. The transplant evolution method and its two-level modification are new evolutionary algorithms proposed in this work, which were used for optimization of structure and parameters of general controllers control algorithms. The transplant evolution algorithm and its extended two-level modification are described in detail in next chapters. The proper settings of evolutionary algorithms are important for minimization the time of optimization and for finds results approaching the global optimum. For proper setting the parameters of differential evolution was created meta-evolution algorithm that is described in chapter named meta-evolution. The basic concepts of control, chosen methods of system identification and controller parameters settings are described in next part. This part describes algorithms of digital controllers and some specific methods uses in digital control. The demonstrations of control algorithm optimizations of various types of controllers are showed in experimental part. The optimized algorithms of general controllers are compared with various types of PSD controllers which were set by various algebraic methods or differential evolution for various models of systems. In the conclusion of this work is stated a recommendation for further development of evolutionary optimization of controllers are focusing on parallel and distributed computing.
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Sandia workshop: úloha z mechaniky konstrukcí
Chleboun, Jan
A frame with uncertain material data is considered. The Young modulus is represented through a random field whose characteristics are not known. The frame response to a given lood is to be assessed on the basis of a limited number of measurements of local and effective Young modulus values. The contribution presents an approach based on probability, fuzzy set, and the worst scenario tools.
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A note on tension spline
Segeth, Karel
Spline theory is mainly grounded on two approaches: the algebraic one (where splines are understood as piecewise smooth functions) and the variational one (where splines are obtained via minimization of quadratic functionals with constraints). We show that the general variational approach called smooth interpolation introduced by Talmi and Gilat covers not only the cubic spline but also the well known tension spline (called also spline in tension or spline with tension). We present the results of a 1D numerical example that show the advantages and drawbacks of the tension spline.
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Tvarové funkce pro hierarchické Hermitovy prvky
Segeth, Karel
In the contribution we derive a hierarchic basis for arbitrary order Hermite finite elements in one spatial dimension. We show that this basis has optimal conditioning properties for the resulting discrete algebraic problem and optimal local (projection based) interpolation propertics. The approach shoum in this contribution shall be the basic tool for design of quality H.SUP.2-conforming elements for beam and plate bending problems.
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Poslední trendy v paralelním programování
Jakl, Ondřej
The paper gives a survey on current approaches and trends in programming parallel systems, paying special attention to scientific and high-performance computing. The mainstream tools (libraries, languages, products) for systems with shared and distributed memory are characterized and some novelties like parallel Matlab are introduced.
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Obecný relační datový model s preferencemi
Nedbal, Radim
The aim of the paper is to present a novel, general approach to preference modelling in the framework of the relational data model. To allow nonmonotonic operations, the preferences are defined between sets of relational instances. The aim is the generalization of the relational algebra that is as minimal as possible, in the sense that the formal fundamentlas of the relational data model are preserved. At the same time, the extended model should be formal enough to provide a sound basis for the investigation of other new preference constructors and operations and for new possible applications.
Plný tet:  PDF
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Numerical algorithms for polynomial matrices
Hromčík, Martin ; Šebek, Michael
This report is devoted to new numerical methods for computations with polynomials and polynomial matrices that are encountered when solving the problems of control systems design via the algebraic methods. A distinguishing feature ofour approach is the extensive employment of the discrete Fourier transform tech-niques, namely of the famous Fast Fourier Transform routine and its relation to polynomial interpolation and Z-transform.
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Polynomial Toolbox
Hromčík, M. ; Šebek, M. ; Ježek, Jan
Quite recently the polynomial design methods found a new great field of application outside the control area: the algebraic approach have been used successfully in signal processing and mobile communications. In contrast to the control systems synthesis, polynomials and polynomial matrices with complex coefficients are often required when designing filters, equalizers, decouplers and other components of mobile phones for instance.
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Numerical algorithms for polynomial matrices
Hromčík, Martin ; Šebek, Michael
This report is devoted to new numerical methods for computations with polynomials and polynomial matrices that are encountered when solving the problems of control systems design via the algebraic methods. A distinguishing feature of our approach is the extensive employment of the discrete Fourier transform techniques, namely of the famous Fast Fourier Transform routine and its relation topolynomial interpolation and Z-transform.
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