No (845)
Yes (810)
Number of found documents:
1655
Published from
to
Stav předaných dat a úprava rozdělení vybraných měření 2017
Novák, Jakub; Jiřina jr., M.; Benešová, Michaela
2017 - Czech
Keywords:
typový diagram dodávky; TDD; spotřeba plynu; měřící místa; kritéria; filtrace; náhrady
Available at various institutes of the ASCR
Stav předaných dat a úprava rozdělení vybraných měření 2017
Popis TDD modelu verze 3.8.
Novák, Jakub; Jiřina jr., M.; Benešová, Michaela
2017 - Czech
Keywords:
typový diagram dodávky; TDD; spotřeba plynu; popis modelu
Available at various institutes of the ASCR
Popis TDD modelu verze 3.8.
Exact Inference In Robust Econometrics under Heteroscedasticity
Kalina, Jan; Peštová, Barbora
2017 - English
The paper is devoted to the least weighted squares estimator, which is one of highly robust estimators for the linear regression model. Novel permutation tests of heteroscedasticity are proposed. Also the asymptotic behavior of the permutation test statistics of the Goldfeld-Quandt and Breusch-Pagan tests is investigated. A numerical experiment on real economic data is presented, which also shows how to perform a robust prediction model under heteroscedasticity. Theoretical results may be simply extended to the context of multivariate quantiles
Keywords:
heteroscedasticity; robust statistics; regression; diagnostic tools; economic data
Fulltext is available at external website.
Exact Inference In Robust Econometrics under Heteroscedasticity
The paper is devoted to the least weighted squares estimator, which is one of highly robust estimators for the linear regression model. Novel permutation tests of heteroscedasticity are proposed. Also ...
On the Optimization of Initial Conditions for a Model Parameter Estimation
Matonoha, Ctirad; Papáček, Š.; Kindermann, S.
2017 - English
The design of an experiment, e.g., the setting of initial conditions, strongly influences the accuracy of the process of determining model parameters from data. The key concept relies on the analysis of the sensitivity of the measured output with respect to the model parameters. Based on this approach we optimize an experimental design factor, the initial condition for an inverse problem of a model parameter estimation. Our approach, although case independent, is illustrated at the FRAP (Fluorescence Recovery After Photobleaching) experimental technique. The core idea resides in the maximization of a sensitivity measure, which depends on the initial condition. Numerical experiments show that the discretized optimal initial condition attains only two values. The number of jumps between these values is inversely proportional to the value of a diffusion coefficient D (characterizing the biophysical and numerical process). The smaller value of D is, the larger number of jumps occurs.
Keywords:
FRAP; sensitivity analysis; optimal experimental design; parameter estimation; finite differences
Available in digital repository of the ASCR
On the Optimization of Initial Conditions for a Model Parameter Estimation
The design of an experiment, e.g., the setting of initial conditions, strongly influences the accuracy of the process of determining model parameters from data. The key concept relies on the analysis ...
Idempotents, Group Membership and their Applications
Porubský, Štefan
2017 - English
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.
Keywords:
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
Available on request at various institutes of the ASCR
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 ...
The Computational Power of Neural Networks and Representations of Numbers in Non-Integer Bases
Šíma, Jiří
2017 - English
We briefly survey the basic concepts and results concerning the computational power of neural networks which basically depends on the information content of weight parameters. In particular, recurrent neural networks with integer, rational, and arbitrary real weights are classified within the Chomsky and finer complexity hierarchies. Then we refine the analysis between integer and rational weights by investigating an intermediate model of integer-weight neural networks with an extra analog rational-weight neuron (1ANN). We show a representation theorem which characterizes the classification problems solvable by 1ANNs, by using so-called cut languages. Our analysis reveals an interesting link to an active research field on non-standard positional numeral systems with non-integer bases. Within this framework, we introduce a new concept of quasi-periodic numbers which is used to classify the computational power of 1ANNs within the Chomsky hierarchy.
Keywords:
neural network; Chomsky hierarchy; beta-expansion; cut language
Available at various institutes of the ASCR
The Computational Power of Neural Networks and Representations of Numbers in Non-Integer Bases
We briefly survey the basic concepts and results concerning the computational power of neural networks which basically depends on the information content of weight parameters. In particular, recurrent ...
Vývoj a ověření nového modelu tepelných poměrů městského prostředí v jemném měřítku
Resler, Jaroslav; Krč, Pavel; Belda, Michal; Juruš, Pavel; Benešová, N.; Lopata, J.; Vlček, O.; Damašková, D.; Eben, Kryštof; Derbek, P.; Maronga, P.; Kanani-Sühring, F.
2017 - Czech
Naším úkolem v rámci projektu UrbanAdapt bylo kvantifikovat dopady různých scénářů rozvoje města na kvalitu ovzduší a tepelný komfort obyvatel v prostoru uličních kaňonů. Z toho vyplývá potřeba modelu, který je schopen simulovat proudění v jemném rozlišení (jednotky metrů) a dostatečně realisticky predikovat turbulence ve složitém terénu uliční sítě a v okolí budov. Takovým požadavkům vyhovují LES modely, avšak rešerše ukázala, že volně dostupný LES model, který by zároveň popisoval energetickou výměnu v městském prostředí, interakci toků energie a proudění vzduchu včetně efektů vegetace a různých vlastností městských povrchů a materiálů v praxi zatím neexistoval. Proto jsme se rozhodli rozšířit existující LES model PALM o nový modul USM (Urban Surface Model) popisující nejdůležitější procesy energetické výměny v městském prostředí. Model by ověřován proti měřením získaným IR kamerou během měřící kampaně v průběhu vlny veder v červenci 2015. The assessment of different scenarios of the city development to air quality and thermal comfort in the areas of street canyons was our main goal inside the project UrbanAdapt. It follows the need for a model which allows to simulate air flows in fine resolution of the order of meter and realistically predict turbulence in the complex terrain of streets and buildings. The LES models comply with such requirements but the review showed that there was no free available LES model which could model the energy exchange in urban environment, i.e. the interaction of energy and air flows including effects of vegetation and different properties of urban surfaces and materials. Thus we decided to extend the existing LES model PALM by a new module USM (Urban Surface Model) which describes the most important energy exchanges in the urban environment. The validation of the model was done against observations obtained by IR camera in the course of heat wave episode in July 2015.
Keywords:
urban surface model; PALM; LES; urban modelling; turbulent flow; energy balance; radiative transfer model; UHI
Available at various institutes of the ASCR
Vývoj a ověření nového modelu tepelných poměrů městského prostředí v jemném měřítku
Naším úkolem v rámci projektu UrbanAdapt bylo kvantifikovat dopady různých scénářů rozvoje města na kvalitu ovzduší a tepelný komfort obyvatel v prostoru uličních kaňonů. Z toho vyplývá potřeba ...
Modelové vyhodnocení urbanistických scénářů na kvalitu ovzduší a tepelný komfort v uliční síti
Resler, Jaroslav; Krč, Pavel; Belda, Michal; Juruš, Pavel; Benešová, N.; Vlček, O.; Damašková, D.; Eben, Kryštof; Derbek, P.
2017 - Czech
V projektu UrbanAdapt byl vyvinut nový model pro simulaci městského prostředí USM integrovaný do LES modelu PALM. Model umožňuje výpočet proudění vzduchu, radiačního záření, teplot vzduchu i materiálů země a zdí, kvality ovzduší a indexů MRT a PET ve velmi jemném měřítku. Pro výpočet scénářů byla ve spolupráci s IPR Praha jako pilotní vybrána oblast Holešovic v okolí křižovatky ulic Komunardů a Dělnická. Navržené scénáře zahrnovaly jak změny zástavby oblasti, zhodnocení různých typů výsadby zeleně a citlivostní studii na vliv barvy materiálů zdí, střech, silnic a chodníků. A new model for simulations of urban environment USM was developed and integrated into LES model PALM inside the project UrbanAdapt. The model allows simulations of air flow, radiation, air temperature and temperature of materials, air pollution and indices MRT and PET in fine resolution. The surrounding of a crossroad of the streets Komunardu and Delnicka in Praha-Holesovice was chosen as a pilot area in collaboration with IPR Prague. Studied scenarios included changes of housing development as well as assessment of different types of plant canopy and sensitivity studies of the colour of walls, roofs, streets and pavements.
Keywords:
USM; PALM; LES; UHI; air quality; development scenarios
Available at various institutes of the ASCR
Modelové vyhodnocení urbanistických scénářů na kvalitu ovzduší a tepelný komfort v uliční síti
V projektu UrbanAdapt byl vyvinut nový model pro simulaci městského prostředí USM integrovaný do LES modelu PALM. Model umožňuje výpočet proudění vzduchu, radiačního záření, teplot vzduchu i materiálů ...
UFO 2017. Interactive System for Universal Functional Optimization
Lukšan, Ladislav; Tůma, Miroslav; Matonoha, Ctirad; Vlček, Jan; Ramešová, Nina; Šiška, M.; Hartman, J.
2017 - English
This report contains a description of the interactive system for universal functional optimization UFO, version 2017. This version contains interfaces to the MATLAB and SCILAB graphics environments.
Keywords:
numerical optimization; nonlinear programming; nonlinear approximation; algorithms; software systems
Available in digital repository of the ASCR
UFO 2017. Interactive System for Universal Functional Optimization
This report contains a description of the interactive system for universal functional optimization UFO, version 2017. This version contains interfaces to the MATLAB and SCILAB graphics environments.
Application and Misapplication of the Czechoslovak STP Cipher During WWII - Report on an Unpublished Manuscript
Porubský, Štefan
2017 - English
Keywords:
STP cipher; Josef Růžek; Karol Cigáň; František Moravec; Czechoslovak military cryptography; Word War II
Available on request at various institutes of the ASCR
Application and Misapplication of the Czechoslovak STP Cipher During WWII - Report on an Unpublished Manuscript
NRGL provides central access to information on grey literature produced in the Czech Republic in the fields of science, research and education. You can find more information about grey literature and NRGL at service web
Send your suggestions and comments to nusl@techlib.cz
Provider
Other bases