Prohlížení Acta Polytechnica. 2014, vol. 54 dle názvu

Zobrazují se záznamy 42-61 z 73

    • NOx PREDICTION FOR FBC BOILERS USING EMPIRICAL MODELS 

      Autor: Štefanica , Jiří; Hrdlička , Jan
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      Reliable prediction of NOx emissions can provide useful information for boiler design and fuel selection. Recently used kinetic prediction models for FBC boilers are overly complex and require large computing capacity. ...

    • OBLIQUE MAGNETIC FIELDS AND THE ROLE OF FRAME DRAGGING NEAR ROTATING BLACK HOLE 

      Autor: Karas , Vladimír; Kopáček , Ondřej; Kunneriath , Devaky
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      Magnetic null points can develop near the ergosphere boundary of a rotating black hole by the combined effects of strong gravitational field and the frame-dragging mechanism. The induced electric component does not vanish ...

    • ON OBSERVATIONAL PHENOMENA RELATED TO KERR SUPERSPINARS 

      Autor: Stuchlik , Zdenek; Schee , Jan
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      We investigate possible signatures of a Kerr naked singularity (superspinar) in various observational phenomena. It has been shown that Kerr naked singularities (superspinars) have to be efficiently converted to a black ...

    • ON THE REAL MATRIX REPRESENTATION OF PT-SYMMETRIC OPERATORS 

      Autor: Fernández M., Francisco
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      We discuss the construction of real matrix representations of PT-symmetric operators. We show the limitation of a general recipe presented some time ago for non-Hermitian Hamiltonians with antiunitary symmetry and propose ...

    • ON TWO WAYS TO LOOK FOR MUTUALLY UNBIASED BASES 

      Autor: Kibler R., Maurice
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      Two equivalent ways of looking for mutually unbiased bases are discussed in this note. The passage from the search for d+1 mutually unbiased bases in Cd to the search for d(d+1) vectors in Cd2 satisfying constraint relations ...

    • OPTIMIZING THE WELDING OF PLASTICS WITH THE USE OF DIFFERENTIAL SCANNING CALORIMETRY AND THERMOGRAVIMETRIC ANALYSIS 

      Autor: Ondruška , Michal; Drienovský , Marián; Čička , Roman; Marônek , Milan; Náplava , Antonín
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      Plastics have different thermal stability, depending on the structure of the polymer chains. It is therefore very important to know their thermal properties, which influence the temperature regime of processing equipment. ...

    • PHOTOMETRIC ANALYSIS OF PI OF THE SKY DATA 

      Autor: Opiela , Rafał; Małek , Katarzyna; Mankiewicz , Lech; Siudek , Małgorzata; Sokołowski , Marcin; Zarnecki Filip, Aleksander
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      Pi of the Sky is a system of two wide field of view robotic telescopes, which search for short timescale astrophysical phenomena, especially for prompt optical GRB emissions. The system was designed for autonomous operation, ...

    • “PI OF THE SKY” OFF-LINE EXPERIMENT WITH GLORIA 

      Autor: Majcher , Ariel; Cwiek , Arkadiusz; Cwiok , Mikołaj; Mankiewicz , Lech; Zaremba , Marcin; Zarnecki F., Aleksander
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      GLORIA is the first free and open-access network of robotic telescopes in the world. Based on the Web 2.0 environment, amateur and professional users can do research in astronomy by observing with robotic telescope, and/or ...

    • RESONANT SWITCH MODEL OF HF QPOS AND EQUATIONS OF STATE OF NEUTRON STARS AND QUARK STARS 

      Autor: Stuchlík , Zdenek; Urbanec , Martin; Kotrlová , Andrea; Török , Gabriel; Goluchová , Katerina
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      The mass and spin estimates of the 4U 1636−53 neutron star obtained by the Resonant Switch (RS) model of high-frequency quasi-periodic oscillations (HF QPOs) are tested by a large variety of equations of state (EoS) governing ...

    • SEARCH FOR ISOLATED BLACK HOLES: PAST, PRESENT, FUTURE 

      Autor: Karpov , Sergey; Beskin , Grigory; Plokhotnichenko , Vladimir
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      The critical property of a black hole is the presence of an event horizon. It may be detected only by means of a detailed study of the emission features of its surroundings. The temporal resolution of such observations has ...

    • SEGMENTING TAGGED CARDIAC MRI DATA USING A LOCAL VARIANCE FILTER 

      Autor: Oberhuber , Tomáš; Kučera , Slavomír; Loucký , Jakub; Súkupová , Lucie; Tintěra , Jaroslav
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      We present a new method for segmenting tagged MRI data. It is based on the observation that the tagging grid vanishes almost immediately inside the ventricles because of the blood flow. Segmentation can be therefore driven ...

    • SEMICLASSICAL ASYMPTOTICS OF EIGENVALUES FOR NON-SELFADJOINT OPERATORS AND QUANTIZATION CONDITIONS ON RIEMANN SURFACES 

      Autor: Esina I., Anna; Shafarevich I., Andrei
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      This paper reports a study of the semiclassical asymptotic behavior of the eigenvalues of some nonself-adjoint operators that are important for applications. These operators are the Schrödinger operator with complex periodic ...

    • SHAPE OF A NUCLEUS GROWING ON STRONGLY CURVED SURFACE OF A NANOFIBER 

      Autor: Sveshnikov , Alexey; Demo , Pavel; Kožíšek , Zdeněk; Tichá , Petra
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      The equilibrium shape of a critical nucleus has strong impact on important parameters of nucleation theory, such as nucleation rate. While on the flat substrate the growing nucleus has a shape of a spherical cap, a shape ...

    • SIZE ANALYSIS OF SOLID PARTICLES AT THE EXPERIMENTAL DEVICE FOR MULTI-STAGE BIOMASS COMBUSTION 

      Autor: Hrnčířová , Michaela; Špiláček , Michal; Pospíšil , Jiří
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      This paper presents the results of an analysis of ash content particles produced in biomass combustion at an experimental device. The main parts of the device are: the water heater, the gasifying chamber, the air preheater, ...

    • SPECIFIC EMISSIONS FROM BIOMASS COMBUSTION 

      Autor: Skopec , Pavel; Hrdlička , Jan; Kaválek , Michal
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      This paper deals with determining the specific emissions from the combustion of two kinds of biomass fuels in a small-scale boiler. The tested fuels were pellets made of wood and pellets made of rape plant straw. In order ...

    • STABILITY OF BOSE-EINSTEIN CONDENSATES IN A PT-SYMMETRIC DOUBLE-δ POTENTIAL CLOSE TO BRANCH POINTS 

      Autor: Löhle, Andreas; Cartarius, Holger; Haag, Daniel; Dast, Dennis; Main, Jörg; Wunner, Günter Wunner
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      A Bose-Einstein condensate trapped in a double-well potential, where atoms are incoupled to one side and extracted from the other, can in the mean-field limit be described by the nonlinear Gross-Pitaevskii equation (GPE) ...

    • STABILIZATION TIME AS AN IMPORTANT PARAMETER AFTER DENSIFICATION OF SOLID BIOFUELS 

      Autor: Križan , Peter; Matúš , Miloš; Beniak , Juraj; Kováčová , Monika
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      The aim of this paper is to present some preliminary results from experimental research on the densification process of solid high-grade biofuels. The findings presented in this paper contribute to an investigation of the ...

    • STATIC TESTS OF UNCONVENTIONAL PROPULSION UNITS FOR ULTRALIGHT AIRPLANES 

      Autor: Helmich , Martin
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      This paper presents static tests of a new unconventional propulsion unit for small aviation airplanes. Our laboratory stand – a fan drive demonstrator – enables us to compare various design options. We performed experiments ...

    • STATISTICAL PROPERTIES OF GRB AFTERGLOW PARAMETERS AS EVIDENCE OF COSMOLOGICAL EVOLUTION OF THEIR HOST GALAXIES 

      Autor: Beskin , Gregory; Oganesyan , Gor; Greco , Giuseppe; Karpov , Sergey
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      The results of a study of 43 peaked R-band light curves of optical counterparts of gamma-ray bursts with known redshifts are presented. The parameters of optical transients were calculated in the comoving frame, and then ...

    • STIRRED FLUIDIZED-BED DRYER OF REGENERATED ION EXCHANGER PARTICLES 

      Autor: Pěnička , Michal; Hoffman , Pavel; Fořt , Ivan
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      This article describes intensification of the fluidized-bed drying process for regenerated spherical-shape ion exchanger particles in the batch mode, achieved by a mechanical stirrer in the fluidized bed layer of the dried ...