Now showing items 21-40 of 326

    • Stability of composite plates with non-uniform distribution of constituents. 

      Michalak, Bohdan (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2004)
      This contribution deals with stability of certain composite plates with a deterministic material structure which is not periodic but can be approximately regarded as periodic in small regions of a plate. The formulation ...
    • On the stress intensity factors for transient thermal loading in an orthotropic thin plate with a crack. 

      Rogowski, Bogdan (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2004)
      This paper is concerned with an orthotropic thin plate containing a crack perpendicular to its surfaces. It is assumed that the transient thermal stress is set up by the application of a heat flux as a function of time and ...
    • Energy method for position stability analysis of critical points of robot manipulators. 

      Szumiński, Przemysław; Kapitaniak, Tomasz; Stefański, Andrzej (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2004)
      An energy method for the position stability analysis of critical points (equilibrium positions) of dynamical systems with an arbitrary finite number of degrees of freedom is presented. The method proposed consists in the ...
    • Effect of changes in the thickness of a perforated plate of the heat exchanger on its structural stability. 

      Chudzik, Agnieszka; Świniarski, Jacek (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2004)
      One of the most important elements of heat exchangers are perforated bottoms. These are perforated plates of significant thickness, in which heating cartridge pipes are mounted. For the designers of heat exchangers, the ...
    • Some remarks on dynamic results for averaged and exact models of thin periodic plates. 

      Jędrysiak, Jarosław; Michalak, Bohdan (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2005)
      The aim of the paper is to show certain justification of the new non-asymptotic model of thin periodic plates, derived using the tolerance averaging (Wo?niak and Wierzbicki, 2000). The model describes the effect of periodicity ...
    • On the contact problem for a smooth punch in piezoelectroelasticity. 

      Dyka, Ewa; Rogowski, Bogdan (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2005)
      The problem of electroelasticity for piezoelectric materials is considered. For axially symmetric states, three potentials are introduced, which determine displacements, electric potential, stresses, components of the ...
    • On stability of thin periodically, densely stiffened cylindrical shells. 

      Tomczyk, Barbara (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2005)
      The aim of this contribution is to propose a new averaged nonasymptotic model of stationary stability problems for thin linear-elastic cylindrical shells reinforced by stiffeners which are periodically, densely spaced along ...
    • Modelling damage processes of concrete at high temperature with thermodynamics of multi-phase porous media. 

      Gawin, Dariusz; Pesavento, Francesco; Schrefler, Bernhard A. (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2006)
      In this paper, the authors present a mathematical description of a multi-phase model of concrete based on the second law of thermodynamics. Exploitation of this law allowed researchers to obtain definitions and constitutive ...
    • Interactive buckling in thin-walled beam-columns with widthwise varying orthotropy. 

      Kubiak, Tomasz (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2006)
      An analysis of local buckling of thin-walled beam-columns, taking account global precritical bending within the first order approximation, is presented in the paper. The problem of interactive buckling of the structure is ...
    • On the modelling of heat conduction in a non-periodically laminated layer. 

      Jędrysiak, Jarosław; Radzikowska, Alina (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2007)
      Heat conduction in a thick layer made of non-periodically distributed micro-laminas of two rigid conductors is considered. Macroscopic properties of the layer are continuously graded across its thickness (FGL layer). The ...
    • Occurrence of strick-slip phenomenon. 

      Awrejcewicz, Jan; Olejnik, Paweł (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2007)
      A self-excited system wit h unilateral friction contact modelled by a two degrees-of-freedom mechanical system, where the normaI farce varies during displacement of a block has been studied. The constructed real laboratory ...
    • Asymptotic study of elastic half-plane with embedded punch. 

      Andrianov, Igor V.; Awrejcewicz, Jan; Kirichek, Yurii A.; Koblik, Steve G. (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2007)
      A contact problem for an elastic half-plane and an embedded rigid punch is studied. The employed mathematical model describes the behavior of a soil with embedded foundation. The analytical solution geverning the stress ...
    • Application of active magnetic bearings for identification of the force generated in the labirynth seal. 

      Kozanecka, Dorota; Kozanecki, Zbigniew; Lech, Tomasz; Kaczmarek, Andrzej (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2007)
      A magnetic bearing system of a rotating shaft is characterized by a unique feature that consists in the possibility of monitoring static and dynamic loads (reactions) of each bearing under normaI operation of the machine. ...
    • The finite element model of the human rib cage. 

      Awrejcewicz, Jan; Łuczak, Bartosz (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2007)
      In the paper, finite element analysis of the rib cage model is applied to recognize stress distributions and to determine the rate of bone fractures (especially for pathologically changed bones). Two thorax models are ...
    • The triple pendulum with barriers and the piston - connecting rod - cranckshaft model. 

      Awrejcewicz, Jan; Kudra, Grzegorz (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2007)
      A model of a flat triple pendulum with obstacles imposed on its position is used for the modelling of a piston-connecting rod-cranks haft system of a mono-cylinder four-stroke combustion engine. The introduced self-excited ...
    • Analysis of stability of the human gait. 

      Mrozowski, Jerzy; Awrejcewicz, Jan; Bamberski, Piotr (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2007)
      Analysis of the gait stability of a man moving along an even surface with a constant velocity is presented. The stability criteria applied to biped robots, namely: the Zero Moment Point (ZMP) and the Ground projection of ...
    • Sposoby modelowania dynamiki szlifierek z uwzględnieniem drgań karbujących. 

      Pawłowski, Witold; Oryński, Franciszek (Stowarzyszenie Inżynierów i Techników Mechaników Polskich, 2008)
      Przedstawiono problem modelowania procesu szlifowania z uwzględnieniem samowzbudnych drgań karbujących. Opisano metody jego modelowania oraz przegląd światowych dokonań w tym zakresie. Analizę przeprowadzono w celu określenia ...
    • Lyapunov exponents of systems with noise and fluctuating parameters. 

      Stefański, Andrzej (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2008)
      This paper deals with the problem of determination of Lyapunov exponents in dynamical systems with noise or fluctuating parameters. The method for identifying the character of motion in such systems is proposed. This ...
    • Large deformation analysis using a quasi-static material point method. 

      Beuth, L.; Benz, T.; Vermeer, Pieter A.; Więckowski, Zdzisław (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2008)
      The Finite Element Method (FEM) has become the standard tool for the analysis of a wide range of solid mechanics problems. However, the underlying structure of a classical updated Lagrangian FEM is not well suited for the ...
    • Non-linear vibrations of the axially moving paper web. 

      Marynowski, Krzysztof (Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej, 2008)
      Non-linear vibrations of the beam-like model of an axially moving paper web with time-dependent tension have been investigated in this paper. The considered paper parameters have been determined experimentally. The beam ...