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Visualization of Large Amount of Spectra in Virtual Observatory Environment

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International Journal of Automation and computing 2014年第6期11卷 613-620页

作者： petr aloun David Andrei petr koda Ivan Zelinka Department of Computer Science Faculty of Electrical Engineering and Computer Science VB-Technical University of Ostrava17.listopadu 15 708 33 Ostrava-Poruba Czech Republic Astronomical Institute of the Academy of Sciences Fricova 298 251 65 Ondrejov Czech Republic

This paper presents overview of new features so far prepared for new version of spectral analysis tool SPLAT-VO that allows to retrieve a large amount of spectra(and other data) based on its characteristics by detailed querying a virtual observatory s resources. The overview is focused on enhancements of user experience, work with simple application messaging protocol(SAMP) and other interoperability that improves work with global list of spectra, plot window and analysis menu.

关键词： SPLAT-VO virtual observatory spectra simple application message protocol (SAMP) flexible image transport system (FITS)

AN ANP/DNP ANALYSIS OF ECONOMIC ELEMENTS IN TODAY’S WORLD NETWORK ECONOMY

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Journal of Systems Science and Systems Engineering 2006年第2期15卷 131-140页

作者： petr FIALA Department of Econometrics University of EconomicsPragueThe Czech Republic

The network economy is a term for today＇s global relationship among economic elements characterized by massive connectivity. The central act of the new era is to connect everything to everything in deep web networks at many levels of mutually interdependent relations, where resources and activities are shared, markets are enlarged and costs and risk are reduced, Network systems contain both positive and negative feedback. A variety of feedback processes create complex system behavior. For such a network the Analytic Network Process （ANP） approach seems to be very appropriate. The ANP method makes it possible to deal systematically with all kinds of dependence and feedback in the system. Dynamic models try to reflect changes in real or simulated time and take into account that the network model components are constantly evolving. Dynamic models use concepts of state variables, flows, and feedback processes. The Dynamic Network Process （DNP） is an extension of ANP that can deal with time deoendent oriorities in a networked economv.

关键词： Network economy positive feedback complementarity Analytic Network Process,Dynamic Network Process

Study on the Numerical Model of Transonic Wind Tunnel Test Section

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Journal of Thermal Science 2021年第1期30卷 231-241页

作者： LOUDA petr PŘÍHODA Jaromír Institute of Thermomechanics of the Czech Academy of Sciences Prague 818200Czech Republic Faculty of Mechanical Engineering Czech Technical UniversityPrague 212135Czech Republic

The authors consider numerical simulations of transonic flows through various turbine cascades in a confined channel which approximates boundaries of real wind *** boundaries of the wind tunnel are impermeable or there can be permeable tailboards to diminish shock wave *** mathematical model is based on Favre-averaged Navier-Stokes equations closed by a turbulence model and model of transition to *** mathematical model is solved by an implicit finite volume method with multi-block *** types of turbine blade cascades with subsonic or supersonic inlet are *** results are compared with optical measurements and simulations of periodic *** validity of experimental reference flow parameters in relation to computed flow patterns is discussed.

关键词： perforated wall model transonic wind tunnel turbine blade cascade

Optimal Choice of Weighting Factors in Adaptive Linear Quadratic Control

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International Journal of Automation and computing 2014年第3期11卷 241-248页

作者： Jiri Vojtesek petr Dostal Tomas Bata University in Zlin Faculty of Applied Informatics

Most of the processes in the industry have nonlinear behavior. Control of such processes with conventional control methods could lead to unstable, suboptimal, etc., results. On the other hand, the adaptive control is a technique widely used for controlling of nonlinear systems. The approach here is based on the recursive identification of the external linear model as a linear representation of the originally nonlinear system. The controller then reacts to the change of the working point or disturbances which could occur by the change of the parameters, structure, etc. The polynomial synthesis together with the linear quadratic(LQ) approach is employed here for the controller synthesis. These techniques satisfy basic control requirements such as the stability, the reference signal tracking and the disturbance attenuation. Resulted controller could be tuned with the choice of weighting factors in LQ approach. This work investigates the effect of these factors on control results. Proposed methods are tested on the mathematical model of the isothermal continuous stirred-tank reactor and simulated results are also verified on the real model of the continuous stirred tank reactor.

关键词： Simulation adaptive control recursive identification linear quadratic(LQ) approach continuous stirred-tank reactor(CSTR).

Accurate large-scale simulations of siliceous zeolites by neural network potentials

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npj Computational Materials 2022年第1期8卷 1662-1673页

作者： Andreas Erlebach petr Nachtigall LukášGrajciar Department of Physical and Macromolecular Chemistry Charles UniversityHlavova 812800Prague 2Czech Republic

The computational discovery and design of zeolites is a crucial part of the chemical *** highly accurate while computational feasible protocol for identification of hypothetical siliceous frameworks that could be targeted experimentally is a great *** tackle this challenge,we trained neural network potentials(NNP)with the SchNet architecture on a structurally diverse database of density functional theory(DFT)*** database was iteratively extended by active learning to cover not only low-energy equilibrium configurations but also high-energy transition *** demonstrate that the resulting reactive NNPs retain DFT accuracy for thermodynamic stabilities,vibrational properties,as well as reactive and non-reactive phase *** a showcase,we screened an existing zeolite database and revealed>20k additional hypothetical frameworks in the thermodynamically accessible range of zeolite ***,our NNPs are expected to be essential for future high-throughput studies on the structure and reactivity of siliceous zeolites.

关键词： synthesis zeolite zeolites

Dietary habits of colorectal neoplasia patients in comparison to their first-degree relatives

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World Journal of Gastroenterology 2014年第17期20卷 5025-5030页

作者： Ivana Mikoviny Kajzrlikova petr Vitek Josef Chalupa petr Dite Beskydy Gastrocentre Department of Internal MedicineHospital Frydek-Mistek73818 Frydek-MistekCzech Republic Center of Gastroenterology Department of Internal MedicineUniversity of OstravaFaculty of Medicine70852 OstravaCzech Republic

AIM: To compare the dietary habits between colorectal neoplasia patients, their first-degree relatives, and unrelated controls.

关键词： Colorectal neoplasms Family Food habits Risk factors Mass screening

Configuration-Sensitive Molecular Sensing on Doped Graphene Sheets

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Nano Research 2010年第7期3卷 472-480页

作者： John Russell petr Král Department of Chemistry University of Illinois at ChicagoChicagoIL 60607USA

We show by molecular dynamics simulations that configuration-sensitive molecular spectroscopy can be realized on optimally doped graphene sheets vibrated by an oscillatory electric *** selectivity of the spectroscopy is achieved by maximizing Coulombic binding between the detected molecule and a specific nest,formed for this molecule on the graphene sheet by substituting selected carbon atoms with boron and nitrogen *** can detect binding of different isomers to the nest from the frequency shifts of selected vibrational modes of the combined *** an illustrative example,we simulate detection of hexanitrostilbene enantiomers in chiral nests formed on graphene.

关键词： Molecular sensing enantiomer graphene functionalization molecular dynamics

Analysis of the instability growth rate during the jet-background interaction in a magnetic field

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Research in Astronomy and Astrophysics 2013年第6期13卷 687-694页

作者： Miroslav Horky petr Kulhnek Czech Technical University in Prague Faculty of Electrical Engineering Department of PhysicsTechnick 2166 27 Prague Czech Republic Astronomical Institute of the Academy of Sciences of the Czech Republic Bocn' Ⅱ 1401/1a 141 31 Prague 4 Czech Republic

The two-stream instability is common, responsible for many observed phe- nomena in nature, especially the interaction of jets of various origins with the back- ground plasma （e.g. extragalactic jet interacting with the cosmic background）. The dispersion relation that does not consider magnetic fields is described by the well- known Buneman relation. In 2011, Bohata, Bren and Kulhanek derived the relation for the two-stream instability without the cold limit, with the general orientation of a magnetic field, and arbitrary stream directions. The maximum value of the imaginary part of the individual dispersion branches ωn（k） is of interest from a physical point of view. It represents the instability growth rate which is responsible for the onset of turbulence mode and subsequent reconnection on the scale of the ion radius accom- panied by a strong plasma thermalization. The paper presented here is focused on the non-relativistic instability growth rate and its dependence on various input parameters, such as magnitude and direction of magnetic field, sound velocity, plasma frequency of the jet and direction of the wave vector during the jet - intergalactic medium in- teraction. The results are presented in plots and can be used for determination of the plasma parameter values close to which the strong energy transfer and thermalization between the jet and the background plasma occur.

关键词： plasmas -- methods: numerical -- instabilities -- turbulence -- waves-- MHD

Application of comprehensive two-dimensional gas chromatography with masss pectrometric detection for the analysis of selected drug residues in wastewater and surface water

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Journal of Environmental Sciences 2013年第1期25卷 204-212页

作者： petr Lacina Ludmila Mravcov Milada Vvrov Institute of Chemistry and Technology of Environmental Protection Faculty of ChemistryBrno University of Technology Geotest a.s.Smahova 1244/112Brno 62700Czech Republic

Pharmaceutical residues have become tightly controlled environmental contaminants in recent years, due to their increasing concentration in environmental components. This is mainly caused by their high level of production and everyday consumption. Therefore there is a need to apply new and sufficiently sensitive analytical methods, which can detect the presence of these contaminants even in very low concentrations. This study is focused on the application of a reliable analytical method for the analysis of 10 selected drug residues, mainly from the group of non-steroidal anti-inflammatory drugs （salicylic acid, acetylsalicylic acid, ctofibric acid, ibuprofen, acetaminophen, caffeine, naproxen, mefenamic acid, ketoprofen, and dicofenac）, in wastewaters and surface waters. This analytical method is based on solid phase extraction, derivatization by N-methyl-N-（trimethylsilyl）trifluoroacetamide （MSTFA） and finally analysis by comprehensive two-dimensional gas chromatography with Time-of-Flight mass spectrometric detection （GC×GC- TOF MS）. Detection limits ranged from 0.18 to 5 ng/L depending on the compound and selected matrix. The method was successfully applied for detection of the presence of selected pharmaceuticals in the Svratka River and in wastewater from the wastewater treatment plant in Brno-Modrice, Czech Republic. The concentration of pharmaceuticals varied from one to several hundreds of ng/L in surface water and from one to several tens of μg/L in wastewater.

关键词： non-steroidal anti-inflammatory drugs solid phase extraction derivatization comprehensive two-dimensional gaschromatography surface water wastewater