Prohlížení Acta Polytechnica. 2014, vol. 54 dle názvu

Zobrazují se záznamy 51-70 z 73

    • 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 ...

    • STRUCTURING OF DIAMOND FILMS USING MICROSPHERE LITHOGRAPHY 

      Autor: Domonkos , Mária; Ižák , Tibor; Štolcová , Lucie; Proška , Jan; Demo , Pavel; Kromka , Alexander
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      In this study, the structuring of micro- and nanocrystalline diamond thin films is demonstrated. The structuring of the diamond films is performed using the technique of microsphere lithography followed by reactive ion ...

    • TECHNICAL AND ECONOMIC OPTIMIZATION OF COGENERATION TECHNOLOGY USING COMBUSTION AND GASIFICATION 

      Autor: Lisý , Martin; Baláš , Marek; Špiláček , Michal; Skála , Zdenek
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      This paper presents the technical and economic optimization of new microcogeneration technology with biomass combustion or biomass gasification used for cogeneration of electrical energy and heat for a 200 kW unit. During ...

    • THE COUPLED-CLUSTER APPROACH TO QUANTUM MANY-BODY PROBLEM IN A THREE-HILBERT-SPACE REINTERPRETATION 

      Autor: Bishop F., Raymond; Znojil , Miloslav
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      The quantum many-body bound-state problem in its computationally successful coupled cluster method (CCM) representation is reconsidered. In conventional practice one factorizes the groundstate wave functions |Ψ) = eS |Φ) ...

    • THE EFFECT OF ADDING HYDROGEN ON THE PERFORMANCE AND THE CYCLIC VARIABILITY OF A SPARK IGNITION ENGINE POWERED BY NATURAL GAS 

      Autor: Chríbik , Andrej; Polóni , Marián; Lach , Ján; Ragan , Branislav
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      This paper deals with the influence of blending hydrogen (from 0 to 50% vol.) on the parameters and the cyclic variability of a Lombardini LGW702 combustion engine powered by natural gas. The experimental measurements were ...

    • THE FLOQUET METHOD FOR PT-SYMMETRIC PERIODIC POTENTIALS 

      Autor: Jones F., H.
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      By the general theory of PT-symmetric quantum systems, their energy levels are either real or occur in complex-conjugate pairs, which implies that the secular equation must be real. However, for periodic potentials it is ...

    • THE INFLUENCE OF SIZE FRACTION ON THE COMPRESSIBILITY OF PINE SAWDUST AND THE EFFECTIVENESS CRITERION FOR DENSIFICATION 

      Autor: Matúš , Miloš; Križan , Peter; Kováčová , Monika; Beniak , Juraj
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      Particulate matter from biomass, e.g. wood sawdust, is very diverse. The basic parameter describing the densification process of particulate matter is its compressibility, quantified by the coefficient of compressibility. ...

    • THE OPERATING LOAD OF A DISINTEGRATION MACHINE 

      Autor: Beniak , Juraj; Križan , Peter; Matúš , Miloš; Kováčová , Monika
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      The process of disintegration is affected by a large number of operating and design parameters which have not previously been described in detail. This paper discusses the effect of the disintegrative surface area on the ...

    • TOWARDS EVOLUTIONARY DESIGN OF COMPLEX SYSTEMS INSPIRED BY NATURE 

      Autor: Vítku , Jaroslav; Nahodil , Pavel
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      This paper presents first steps towards evolutionary design of complex autonomous systems. The approach is inspired in modularity of human brain and principles of evolution. Rather than evolving neural networks or neural-based ...

    • TRACKING DOWN LOCALIZED MODES IN PT-SYMMETRIC HAMILTONIANS UNDER THE INFLUENCE OF A COMPETING NONLINEARITY 

      Autor: Bagchi , Bijan; Modak , Subhrajit; Panigrahi K., Prasanta
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2014)
      The relevance of parity and time reversal (PT)-symmetric structures in optical systems has been known for some time with the correspondence existing between the Schrödinger equation and the paraxial equation of diffraction, ...