Now showing items 21-40 of 46865

    • Water-air ejector with conical-cylindrical mixing chamber 

      Author: Sliusenko, Andrii; Ponomarenko, Vitalii; Forostiuk, Inna
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2021)
      In the paper, the hydrodynamics of the liquid-gas mixture in the mixing chamber of the ejectors at different spatial positions was analyzed and the comparative study of such ejectors was carried out. It was found that a ...
    • Determination of bond model for 7-wire strands in pretensioned concrete beam 

      Author: Parkhats, Vadzim; Krzywoń, Rafał; Hulimka, Jacek; Kubica, Jan
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2021)
      A correct choice of a bond model for prestressing tendons is crucial for the right modelling of a structural behaviour of a pretensioned concrete structure. The aim of this paper is the determination of an optimal bond ...
    • Application of additional insulation to ETICS on surfaces with biocorrosion 

      Author: Antošová, Naďa; Šťastný, Patrik; Petro, Marek; Krištofič, Štefan
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2021)
      The paper presents partial outputs from an experiment that demonstrated the impact of applying an additional insulation on an existing contact insulation system with a green-algae surface. The aim was mainly to detect the ...
    • Comparision of the walk techniques for fitness state space analysis in vehicle routing problem 

      Author: Agárdi, Anita; Kovács, László; Bányai, Tamás
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2021)
      The Vehicle Routing Problem (VRP) is a highly researched discrete optimization task. The first article dealing with this problem was published by Dantzig and Ramster in 1959 under the name Truck Dispatching Problem. Since ...
    • Design development and study of an elastic sectional screw operating tool 

      Author: Hevko, Roman; Zalutskyi, Sergii; Tkachenko, Ihor; Lyashuk, Oleg; Trokhaniak, Oleksandra
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2021)
      The results of an elastic sectional screw operating tool development and its production technique are presented in the article under consideration. The operating tool has been made to fix the elastic sections, providing ...
    • Cavitation wear of Eurofer 97, Cr18Ni10Ti and 42HNM alloys 

      Author: Rostova, Hanna; Voyevodin, Victor; Vasilenko, Ruslan; Kolodiy, Igor; Kovalenko, Vladimir; Marinin, Vladimir; Zuyok, Valeriy; Kuprin, Alexander
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2021)
      The microstructure, hardness and cavitation wear of Eurofer 97, Cr18Ni10Ti and 42HNM have been investigated. It was revealed that the cavitation resistance of the 42HNM alloy is by an order of magnitude higher than that ...
    • Delamination of polyimide in hydrofluoric acid 

      Author: Al-mashaal, Asaad K. Edaan; Cheung, Rebecca
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2021)
      Wet etching is a critical fabrication step for the mass production of micro and nanoelectronic devices. However, when an extremely corrosive acid such as hydrofluoric (HF) acid are used during etching, an undesirable damage ...
    • Performance characteristics of low carbon waste material to stabilise soil with extremely high plasticity 

      Author: Al-Baidhani, Ali; Al-Taie, Abbas Jawad
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2021)
      The application of low-carbon and natural materials to mitigate the undesired properties of difficult soils is considered as a sustainable solution to the issues regarding these soils. Selecting some natural materials, of ...
    • Orthonormal polynomial projection quantization: an algebraic eigenenergy bounding method 

      Author: Handy, Carlos R.
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2022)
      The ability to generate tight eigenenergy bounds for low dimension bosonic or ferminonic, hermitian or non-hermitian, Schrödinger operator problems is an important objective in the computation of quantum systems. Very few ...
    • Linearised coherent states for non-rational SUSY extensions of the harmonic oscillator 

      Author: Contreras-Astorga, Alonso; Fernández C., David J.; Muro-Cabral, César
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2022)
      In this work, we derive two equivalent non-rational extensions of the quantum harmonic oscillator using two different supersymmetric transformations. For these extensions, we built ladder operators as the product of the ...
    • Generalized three-body harmonic oscillator system: ground state 

      Author: Escobar-Ruiz, Adrian M.; Montoya, Fidel
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2022)
      In this work we report on a 3-body system in a d−dimensional space ℝd with a quadratic harmonic potential in the relative distances rij = |ri −rj| between particles. Our study considers unequal masses, different spring ...
    • Time-dependent mass oscillators: constants of motion and semiclasical states 

      Author: Zelaya, Kevin
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2022)
      This work reports the construction of constants of motion for a family of time-dependent mass oscillators, achieved by implementing the formalism of form-preserving point transformations. The latter allows obtaining a ...
    • Photonic graphene under strain with position-dependent gain and loss 

      Author: Castillo-Celeita, Miguel; Contreras-Astorga, Alonso; Fernández C., David J.
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2022)
      We work with photonic graphene lattices under strain with gain and loss, modeled by the Dirac equation with an imaginary mass term. To construct such Hamiltonians and their solutions, we use the free-particle Dirac equation ...
    • From quartic anharmonic oscillator to double well potential 

      Author: Turbiner, Alexander V.; del Valle, Juan Carlos
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2022)
      Quantum quartic single-well anharmonic oscillator Vao(x) = x2 + g2x4 and double-well anharmonic oscillator Vdw(x) = x2(1−gx)2 are essentially one-parametric, they depend on a combination (g2ℏ). Hence, these problems are ...
    • Time-dependent step-like potential with a freezable bound state in the continuum 

      Author: Gutiérrez Altamirano, Izamar; Contreras-Astorga, Alonso; Raya Montaño , Alfredo
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2022)
      In this work, we construct a time-dependent step-like potential supporting a normalizable state with energy embedded in the continuum. The potential is allowed to evolve until a stopping time ti, where it becomes static. ...
    • About the time evolution of coherent electron states in monolayers of boron allotropes 

      Author: Díaz-Bautista, Erik
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2022)
      In this paper, we theoretically analyze the massless Dirac fermion dynamics in twodimensional monolayers of boron allotropes, 8B and 2BH − pmmn borophene, interacting with external electric and magnetic fields. We study ...
    • Modified Korteweg-de Vries equation as a system with benign ghosts 

      Author: Smilga, Andrei
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2022)
      We consider the modified Korteweg-de Vries equation, uxxx + 6u2ux + ut = 0, and explore its dynamics in spatial direction. Higher x derivatives bring about the ghosts. We argue that these ghosts are benign, i.e., the ...
    • E-knihy ve fondu ÚK ČVUT 

      Author: Šorejsová, Tereza
      (2022)
    • Peculiar aspects of cracking in prestressed reinforced concrete T-beams 

      Author: Karpiuk, Vasyl; Somina, Yuliia; Karpiuk, Fedir; Karpiuk, Irina
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2021)
      In order to study the cracking of prestressed reinforced concrete T-shaped beam structures, the authors planned and carried out a full-scale experiment with five variable factors. The following factors were chosen as ...
    • Quantization of rationally deformed Morse potentials by Wronskian transforms of Romanovski-Bessel polynomials 

      Author: Natanson, Gregory
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2022)
      The paper advances Odake and Sasaki’s idea to re-write eigenfunctions of rationally deformed Morse potentials in terms of Wronskians of Laguerre polynomials in the reciprocal argument. It is shown that the constructed ...