Ne (1032)
Počet nalezených dokumentů:
1032
Publikováno od
do
Variational Analysis and Its Applications
Červinka, Michal
2015 - anglický
The purpose of this meeting is to bring together researchers with common interest in the field. There will be opportunities for informal discussions. Graduate students and others beginning their mathematical career are encouraged to participate.
Klíčová slova:
variational analysis; data applications; geometry
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Variational Analysis and Its Applications
The purpose of this meeting is to bring together researchers with common interest in the field. There will be opportunities for informal discussions. Graduate students and others beginning their ...
Recursive Estimation of High-Order Markov Chains: Approximation by Finite Mixtures
Kárný, Miroslav
2015 - anglický
A high-order Markov chain is a universal model of stochastic relations between discrete-valued variables. The exact estimation of its transition probabilities suers from the curse of dimensionality. It requires an excessive amount of informative observations as well as an extreme memory for storing the corresponding su cient statistic. The paper bypasses this problem by considering a rich subset of Markov-chain models, namely, mixtures of low dimensional Markov chains, possibly with external variables. It uses Bayesian approximate estimation suitable for a subsequent decision making under uncertainty. The proposed recursive (sequential, one-pass) estimator updates a product of Dirichlet probability densities (pds) used as an approximate posterior pd, projects the result back to this class of pds and applies an improved data-dependent stabilised forgetting, which counteracts the dangerous accumulation of approximation errors.
Klíčová slova:
Markov chain; approximate parameter estimation; Bayesian recursive estimation; adaptive systems; Kullback-Leibler divergence; forgetting
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Recursive Estimation of High-Order Markov Chains: Approximation by Finite Mixtures
A high-order Markov chain is a universal model of stochastic relations between discrete-valued variables. The exact estimation of its transition probabilities suers from the curse of dimensionality. ...
DCTOOL - A1
Bakule, Lubomír; Papík, Martin; Rehák, Branislav
2014 - anglický
DCTOOL - A1 is a documentation of MATLAB routines developed for the design of decentralized control of large scale complex systems.
Klíčová slova:
decentralized control; networked control systems; LQG design
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
DCTOOL - A1
DCTOOL - A1 is a documentation of MATLAB routines developed for the design of decentralized control of large scale complex systems.
Message Embedded Synchronization for the Generalized Lorenz System and Its Use for Chaotic Masking
Čelikovský, Sergej; Lynnyk, Volodymyr
2013 - anglický
This paper implements and analyzes the well-known message embedded synchronization scheme for the case of the generalized Lorenz system. Such a synchronization may be used for chaotic masking scheme using a single channel only. This method was already discussed in the earlier literature for the particular classes of systems. In this paper, a more general class wheremessage embedded synchronization is possible is described. Then, it is shown that the generalized Lorenz system falls within that class. Furthermore, using the resulting synchronization, the novel secure encryption scheme is proposed. It requires very reasonable amount of data to encrypt and time to decrypt one bit. Basically, to encrypt one bit, only one iteration (i.e. only one real number of 6 valid digits) is needed. At the same time, 100 percent of the carrying chaotic signal can be used. The method is also demonstrated by numerical simulations of a digital data encryption and decryption.
Klíčová slova:
chaos synchronization; secury encryption
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Message Embedded Synchronization for the Generalized Lorenz System and Its Use for Chaotic Masking
This paper implements and analyzes the well-known message embedded synchronization scheme for the case of the generalized Lorenz system. Such a synchronization may be used for chaotic masking scheme ...
What the Data Say about the Effects of Fiscal Policy in the Czech Republic?
Baxa, Jaromír
2013 - anglický
In this paper, we provide the estimates of the fiscal multiplier in the Czech economy, based on the methodology of the fiscal VAR. The basic idea, adding fiscal variables into the macroeconomic VAR model, follows Blanchard and Perotti (2002). For estimation of our model, we utilize the dataset with quarterly data on a sample from the first quarter of 1998 to the second quarter of 2009. Our main results are as follows. Firstly, government expenditures have a positive and significant impact on the GDP. By contrast, a response of GDP on a shock to government revenues is slightly negative and in most specifications not significant. Secondly, these results are robust to various sensitivity checks. Consequently, the restoration of sustainable fiscal policy should focus rather on the revenues side than in the government expenditures, since a significant cut in government spending would probably have slowed down economic growth. Finally, we should note, that uncertainty connected with our results is large, namely in comparison with existing studies on the effects of monetary policy.
Klíčová slova:
fiscal policy; vector autoregression
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
What the Data Say about the Effects of Fiscal Policy in the Czech Republic?
In this paper, we provide the estimates of the fiscal multiplier in the Czech economy, based on the methodology of the fiscal VAR. The basic idea, adding fiscal variables into the macroeconomic VAR ...
Scalable Decision Making: Uncertainty, Imperfection, Deliberation, European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases (ECML/PKDD 2013)
Guy, Tatiana Valentine; Kárný, Miroslav
2013 - anglický
Machine learning (ML) and knowledge discovery both use and serve to decision making (DM), which has to cope with uncertainty, incomplete knowledge, problem and data complexity and imperfection (limited cognitive and evaluating capabilities) of the involved heterogeneous multiple participants (aka agents, decision makers, components, controllers, classifiers, etc.). Contemporary DM deals with complex systems characterised by heterogeneous components and their goal-motivated dynamic interactions. The individual participants are selfish, i.e. follow their individual goals. There is no well-justified way to influence or describe the resulting collective behaviour of such a system via a well-proved combination of the selfish components. Economic and natural sciences describe concepts governing the functioning of systems of selfish participants as well as ways influencing their behaviour. However, the majority of solutions rely on the human moderator/manager controlling such a system.
Klíčová slova:
scalable; decision making; uncertainty; imperfection; deliberation
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Scalable Decision Making: Uncertainty, Imperfection, Deliberation, European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases (ECML/PKDD 2013)
Machine learning (ML) and knowledge discovery both use and serve to decision making (DM), which has to cope with uncertainty, incomplete knowledge, problem and data complexity and imperfection ...
DCTOOL
Bakule, Lubomír; Papík, Martin; Rehák, Branislav
2013 - anglický
DCTOOL is a documentation of Matlab routines developed for the design of decentalized control of large scale complex systems.
Klíčová slova:
decentralized control; networked control systems; large scale complex systems
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
DCTOOL
DCTOOL is a documentation of Matlab routines developed for the design of decentalized control of large scale complex systems.
Characteristics of the Chen Attractor
Augustová, Petra; Beran, Zdeněk
2013 - anglický
Within the paper a mathematical representation of the so-called Chen model is described as a particular parametric three-dimensional chaotic dynamical system, i.e. a system of three nonlinear differential equations evolving in time. The main aim of this paper is to find for the Chen system the properties that are known for the Lorenz system and its famous Lorenz attractor. First, the integrals of motion are derived for some parameters of the Chen system. The integrals of motions play an important role in physics, e.g. for conservation laws. Next, the shape of the global attractor of this system is approximated by volumes that contain the attractor. The shape predicts the future behavior of the system. To obtain these results, the already proved fact that the Chen system is a continued transition of the Lorenz system is used. According to our knowledge, the same approach of shifting the known facts about the Lorenz system to a newdynamical system, the Chen system in this context, has not been presented yet.
Klíčová slova:
chaotic dynamical system; Lorenz system; Chen system
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Characteristics of the Chen Attractor
Within the paper a mathematical representation of the so-called Chen model is described as a particular parametric three-dimensional chaotic dynamical system, i.e. a system of three nonlinear ...
Modul pro převod vozidlových signálů na standard PS2
Plíhal, Jiří
2013 - český
Předmětem výzkumné úlohy je HW návrh a vytvoření modulu umožňujícího převod vozidlových signálů (programovatelné pole tlačítek, multifunkční volant Barrelkeys, multifunkční ovládací tlačítka) na standard PS2. Jedná se o ucelený návrh dekodéru včetně vytvoření funkčního vzorku. Technické řešení zahrnuje úlohy: maticové připojení mikrospínačů, připojení ovládacích prvků multifunkčního volantu „Barrelkeys“ pomocí datového přenosu Telenostra, integrace řídící jednotky klávesnicových prvků. The subject of the research task is aimed to proposal and development module for transmission vehicles signals (smart field of buttons, multifunction steering wheel Barrelkeys, multifunction control of buttons) to standard PS2. The whole proposal includes development functional sample of decoder. Technical solution comprises research tasks: interface for matrix micro switch, interface for control elements of multifunction steering wheel "Barelkeys" by means of data transmission Telenostra and integration keyboard control unit.
Klíčová slova:
Human-Machine-Interface; Control Systems; Warning and Assistant Systems; Signal Processing
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Modul pro převod vozidlových signálů na standard PS2
Předmětem výzkumné úlohy je HW návrh a vytvoření modulu umožňujícího převod vozidlových signálů (programovatelné pole tlačítek, multifunkční volant Barrelkeys, multifunkční ovládací tlačítka) na ...
Odhalování kopií pomocí matematického zpracování obrazu, část I: teoretická východiska a princip metody
Blažek, Jan; Hradilová, J.; Zitová, Barbara; Kamenický, Jan
2012 - český
Navrhujeme poloautomatické metody pro geometrické sesazení (dále jen registraci) a pro komparaci digitálních snímků uměleckých děl. Algoritmus registrace je založen na odhadu perspektivní transformace pomocí kontrolních bodů. Porovnání snímků je založeno na statistické analýze snímků, normalizaci jasu a absolutní odchylce. Vhodnost různých metod porovnání je demonstrována na příkladech. Výstupem algoritmů jsou srozumitelné rozdílové mapy. Navrhované metody jsou implementovány ve veřejně dostupné aplikaci Fresco. We propose semi-automatic methods for registration and comparison digital images of fine art. Registration algorithm is based on estimation of perspective transformation parameters according to control points. Image comparison is based on statistical analysis of images, normalization of brightness and absolute deviation. Suitability of comparing algorithms is demonstrated on examples. As an output of comparing algorithms are used intelligible differential maps.
Klíčová slova:
Perspective transformation; perspective; image difference; graphical software
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Odhalování kopií pomocí matematického zpracování obrazu, část I: teoretická východiska a princip metody
Navrhujeme poloautomatické metody pro geometrické sesazení (dále jen registraci) a pro komparaci digitálních snímků uměleckých děl. Algoritmus registrace je založen na odhadu perspektivní transformace ...
NUŠL poskytuje centrální přístup k informacím o šedé literatuře vznikající v ČR v oblastech vědy, výzkumu a vzdělávání. Více informací o šedé literatuře a NUŠL najdete na webu služby.
Vaše náměty a připomínky posílejte na email nusl@techlib.cz
Provozovatel
Zahraniční báze