Assessment of Independent EEG Components Obtained by Different Methods for BCI Based on Motor Imagery
Húsek, Dušan; Frolov, A. A.; Kerechanin, J. V.; Bobrov, P.D.
2021 - anglický Eight methods of decomposition of a multichannel EEG signal are compared in terms of their ability to identify the most physiologically significant components. The criterion for the meaningfulness of a method is its ability to reduce mutual information between components; to create components that can be attributed to the activity of dipoles located in the cerebral cortex; find components that are provided by other methods and for this case; and at the same time, these components should most contribute to the accuracy of the BCI based on imaginary movement. Independent component analysis methods AMICA, RUNICA and FASTICA outperform others in the first three criteria and are second only to the Common Spatial Patterns method in the fourth criterion. The components created by all methods for 386 experimental sessions of 27 subjects were combined into more than 100 clusters containing more than 10 elements. Additionally, the components of the 12 largest clusters were analyzed. They have proven to be of great importance in controlling BCI, their origins can be modeled using dipoles in the brain, and they have been detected by several degradation methods. Five of the 12 selected components have been identified and described in our previous articles. Even if the physiological and functional origins of the rest of identified components’ are to be the subject of further research, we have shown that their physiological nature is at least highly probable.\n Klíčová slova: brain–computer interface; motor imagery; blind source separation; independent component analysis; common spatial patterns; cluster analysis; EEG pattern extraction; EEG analysis; ICA; CSP; BCI; motor imagery Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Assessment of Independent EEG Components Obtained by Different Methods for BCI Based on Motor Imagery

Eight methods of decomposition of a multichannel EEG signal are compared in terms of their ability to identify the most physiologically significant components. The criterion for the meaningfulness of ...

Húsek, Dušan; Frolov, A. A.; Kerechanin, J. V.; Bobrov, P.D.
Ústav informatiky, 2021

Visual Images Segmentation based on Uniform Textures Extraction
Goltsev, A.; Gritsenko, V.; Húsek, Dušan
2020 - anglický A new effective procedure for partial texture segmentation of visual images is proposed. The procedure segments any input image into a number of non-overlapping homogeneous ne-grained texture areas. The main advantages of the proposed procedure are as follows. It is completely unsupervised, that is, it processes the input image without any prior knowledge of either the type of textures or the number of texture segments in the image. In addition, the procedure segments arbitrary images of all types. This means that no changes to the procedure parameters are required to switch from one image type to another. Another major advantage of the procedure is that in most cases it extracts the uniform ne-grained texture segments present in the image, just as humans do. This result is supported by series of experiments that demonstrate the ability of the procedure to delineate uniform ne-grained texture segments over a wide range of images. At a minimum, image processing according to the proposed technique leads to a signficant reduction in the uncertainty of the internal structure of the analyzed image. Klíčová slova: Texture feature; Texture window; Homogeneous ne-grained texture segment; Texture segment extraction; Texture segmentation Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Visual Images Segmentation based on Uniform Textures Extraction

A new effective procedure for partial texture segmentation of visual images is proposed. The procedure segments any input image into a number of non-overlapping homogeneous ne-grained texture areas. ...

Goltsev, A.; Gritsenko, V.; Húsek, Dušan
Ústav informatiky, 2020

The scalar-valued score functions of continuous probability distribution
Fabián, Zdeněk
2019 - anglický In this report we give theoretical basis of probability theory of continuous random variables based on scalar valued score functions. We maintain consistently the following point of view: It is not the observed value, which is to be used in probabilistic and statistical considerations, but its 'treated form', the value of the scalar-valued score function of distribution of the assumed model. Actually, the opinion that an observed value of random variable should be 'treated' with respect to underlying model is one of main ideas of the inference based on likelihood in classical statistics. However, a vector nature of Fisher score functions of classical statistics does not enable a consistent use of this point of view. Instead, various inference functions are suggested and used in solutions of various statistical problems. Inference function of this report is the scalar-valued score function of distribution. Klíčová slova: Shortcomings of probability theory; Scalar-valued score functions; Characteristics of continous random variables; Parametric estimation; Transformed distributions; Skew-symmetric distributions Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. The scalar-valued score functions of continuous probability distribution

In this report we give theoretical basis of probability theory of continuous random variables based on scalar valued score functions. We maintain consistently the following point of view: It is not ...

Fabián, Zdeněk
Ústav informatiky, 2019

Stav předaných dat a úprava rozdělení vybraných měření 2018
Novák, Jakub; Jiřina, M.; Benešová, Michaela
2018 - český Zpráva se týká stavu předávaných dat a úpravy rozdělení vybraných měření pro rok 2018 v rámci projektu TDD-ČR. Cílem je informovat o aktuálním stavu dat a navrhnout opatření pro zachování reprezentativity celého vzorku. Jsou uvedena kritéria filtrace dat a navrženy postupy pro přerozdělení vybraných měření. Klíčová slova: typový diagram dodávky; TDD; spotřeba plynu; měřicí místa; kritéria; filtrace; náhrady Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Stav předaných dat a úprava rozdělení vybraných měření 2018

Zpráva se týká stavu předávaných dat a úpravy rozdělení vybraných měření pro rok 2018 v rámci projektu TDD-ČR. Cílem je informovat o aktuálním stavu dat a navrhnout opatření pro zachování ...

Novák, Jakub; Jiřina, M.; Benešová, Michaela
Ústav informatiky, 2018

Popis TDD modelu verze 3.9
Novák, Jakub; Jiřina, M.; Benešová, Michaela
2018 - český Zpráva je závěrečnou roční zprávou pro rok 2018 v rámci Projektu TDD-ČR. Cílem je předat metodiky pro užití modelu jak provozovatelem distribuční soustavy, tak operátorem trhu a dále informovat o aktuálním stavu modelu. Jsou popsány předávané soubory včetně vzorového výpočtu na reálných datech a jejich obsah. Klíčová slova: typový diagram dodávky; typový diagram dodávky; spotřeba plynu; TDD; popis modelu Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Popis TDD modelu verze 3.9

Zpráva je závěrečnou roční zprávou pro rok 2018 v rámci Projektu TDD-ČR. Cílem je předat metodiky pro užití modelu jak provozovatelem distribuční soustavy, tak operátorem trhu a dále informovat o ...

Novák, Jakub; Jiřina, M.; Benešová, Michaela
Ústav informatiky, 2018

Semigroup Structure of Sets of Solutions to Equation X^s = X^m
Porubský, Štefan
2017 - anglický Using an idempotent semigroup approach we describe the semigroup and group structure of the set of solutions to equation X^m = X^s in successive steps over a periodic commutative semigroup, over multiplicative semigroups of factor rings of residually finite commutative rings and finally over multiplicative semigroups of factor rings of residually finite commutative principal ideal domains. The analysis is done through the use of the maximal subsemigroups and groups corresponding to an idempotent of the corresponding semigroup and in the case of residually finite PID’s employing the available analysis of the Euler-Fermat Theorem as given in [11]. In particular the case when this set of solutions is a union of groups is handled. As a simple application we show a not yet noticed group structure of the set of solutions to x^n = x connected with the message space of RSA cryptosystems and Fermat pseudoprimes. Klíčová slova: set of solutions; idempotent; maximal semigroup corresponding to an idempotent; maximal group corresponding to an idempotent; equation X^s = X^m; finite commutative ring with identity element; residually finite commutative principal ideal domains Plné texty jsou dostupné na vyžádání prostřednictvím repozitáře Akademie věd. Semigroup Structure of Sets of Solutions to Equation X^s = X^m

Using an idempotent semigroup approach we describe the semigroup and group structure of the set of solutions to equation X^m = X^s in successive steps over a periodic commutative semigroup, over ...

Porubský, Štefan
Ústav informatiky, 2017

Stav předaných dat a úprava rozdělení vybraných měření 2017
Novák, Jakub; Jiřina jr., M.; Benešová, Michaela
2017 - český Klíčová slova: typový diagram dodávky; TDD; spotřeba plynu; měřící místa; kritéria; filtrace; náhrady Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Stav předaných dat a úprava rozdělení vybraných měření 2017

Novák, Jakub; Jiřina jr., M.; Benešová, Michaela
Ústav informatiky, 2017

Popis TDD modelu verze 3.8.
Novák, Jakub; Jiřina jr., M.; Benešová, Michaela
2017 - český Klíčová slova: typový diagram dodávky; TDD; spotřeba plynu; popis modelu Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Popis TDD modelu verze 3.8.

Novák, Jakub; Jiřina jr., M.; Benešová, Michaela
Ústav informatiky, 2017

Idempotents, Group Membership and their Applications
Porubský, Štefan
2017 - anglický S.Schwarz in his paper [165] proved the existence of maximal subgroups in periodic semigroups and a decade later he brought [167] into play the maximal subsemigroups and thus he embodied the idempotents in the structural description of semigroups. Later in his papers he showed that a proper description of these structural elements can be used to (re)prove many useful and important results in algebra and number theory. The present paper gives a survey of selected results scattered throughout the literature where an semigroup approach based on tools like idempotent, maximal subgroup or maximal subsemigroup either led to a new insight into the substance of the known results or helped to discover new approach to solve problems. Special attention will be given to some disregarded historical connections between semigroup and ring theory. Klíčová slova: multiplicative semigroup; finite semigroups; power semigroups; idempotent elements; finite commutative rings; principal ideal domain; Euler-Fermat theorem; Wilson theorem; matrices over fields; maximal groups contained in a semigroup; periodic sequence; multiplicative semigroup of Zm; semigroup of circulant Boolean matrices Plné texty jsou dostupné na vyžádání prostřednictvím repozitáře Akademie věd. Idempotents, Group Membership and their Applications

S.Schwarz in his paper [165] proved the existence of maximal subgroups in periodic semigroups and a decade later he brought [167] into play the maximal subsemigroups and thus he embodied the ...

Porubský, Štefan
Ústav informatiky, 2017

Application and Misapplication of the Czechoslovak STP Cipher During WWII - Report on an Unpublished Manuscript
Porubský, Štefan
2017 - anglický Klíčová slova: STP cipher; Josef Růžek; Karol Cigáň; František Moravec; Czechoslovak military cryptography; Word War II Plné texty jsou dostupné na vyžádání prostřednictvím repozitáře Akademie věd. Application and Misapplication of the Czechoslovak STP Cipher During WWII - Report on an Unpublished Manuscript

Porubský, Štefan
Ústav informatiky, 2017