The Experts below are selected from a list of 38979 Experts worldwide ranked by ideXlab platform
Roman Lewandowski - One of the best experts on this subject based on the ideXlab platform.
-
Computational formulation for periodic vibration of geometrically nonlinear structures—part 2: Numerical strategy and examples
International Journal of Solids and Structures, 1997Co-Authors: Roman LewandowskiAbstract:Abstract In this paper the numerical strategy for solving the matrix amplitude equation with parameter is discussed in detail. The matrix amplitude equation is the result of application of the Galerkin method for analysis of periodic solutions of the geometrically nonlinear structures. A theoretical background of the proposed method of analysis is given in a companion paper by Lewandowski [Lewandowski, R. (1996). Computational formulation for periodic vibration of geometrically nonlinear structures—Part 1: theoretical background. International Journal of Solids and Structures34(15), 1925–1947]. An example application of general theory is also presented. Numerical results are given and discussed to show some interesting behaviors of nonlinear structures and to illustrate the numerical efficiency and validity of the suggested method.
-
Computational formulation for periodic vibration of geometrically nonlinear structures—part 1: Theoretical background
International Journal of Solids and Structures, 1997Co-Authors: Roman LewandowskiAbstract:Abstract A general computational formulation for geometrically nonlinear structures excited by harmonic forces and executing periodic motion in a steady-state is presented. The equations of both continuous and discretized models are reformulated to obtain the motion equation in a more suitable form to a further analysis. The multi-harmonic solution of motion equation is written in a form of truncated Fourier series. Next, the Galerkin, Ritz and the harmonic balance method are discussed in a context of their equivalency in derivation of the matrix amplitude equation. The matrix amplitude equation as well as the associated tangent matrix are given in an explicit form. The stability of steady-state solution is discussed by using the Floquet theory. The numerical algorithm and an example application are described in a companion paper by Lewandowski [Lewandowski, R. Computational formulation for periodic vibration of geometrically nonlinear structures—Part 2: Numerical strategy and numerical examples. International Journal of Solids and Structures . (in preparation)].
Andrzej Okolow - One of the best experts on this subject based on the ideXlab platform.
-
New diffeomorphism invariant states on a holonomy-flux algebra
Classical and Quantum Gravity, 2010Co-Authors: Michal Dziendzikowski, Andrzej OkolowAbstract:The theorem by Lewandowski et al stating uniqueness of a diffeomorphism invariant state on an algebra of quantum observables for background-independent theories of connections is based on some technical assumptions imposed on the algebra and the diffeomorphisms. In this paper we present a class of diffeomorphism invariant states on an algebra of this sort, which exist when the algebra and the diffeomorphisms satisfy alternative assumptions.
Michal Dziendzikowski - One of the best experts on this subject based on the ideXlab platform.
-
New diffeomorphism invariant states on a holonomy-flux algebra
Classical and Quantum Gravity, 2010Co-Authors: Michal Dziendzikowski, Andrzej OkolowAbstract:The theorem by Lewandowski et al stating uniqueness of a diffeomorphism invariant state on an algebra of quantum observables for background-independent theories of connections is based on some technical assumptions imposed on the algebra and the diffeomorphisms. In this paper we present a class of diffeomorphism invariant states on an algebra of this sort, which exist when the algebra and the diffeomorphisms satisfy alternative assumptions.
José M. Velhinho - One of the best experts on this subject based on the ideXlab platform.
-
Local Properties of Measures in Quantum Field Theory and Cosmology
Symmetry Integrability and Geometry: Methods and Applications, 2015Co-Authors: José M. VelhinhoAbstract:We show that measure theoretical results concerning the Ashtekar{Lewandowski measure in the space of generalized connections have direct analogues in the context of the Bohr compactification of the line and associated Haar measure. We present also a cha- racterization of the support of the measure associated with the canonical quantization of the free massive scalar field, following closely well known analogous results concerning the Euclidean path integral measure.
-
Denseness of Ashtekar Lewandowski states and a generalized cut-off in loop quantum gravity
Classical and Quantum Gravity, 2005Co-Authors: José M. VelhinhoAbstract:We show that the set of states of the Ashtekar–Isham–Lewandowski holonomy algebra defined by elements of the Ashtekar–Lewandowski Hilbert space is dense in the space of all states. We consider weak convergence properties of a modified version of the cut-off procedure currently in use in loop quantum gravity. This version is adapted to vector states rather than to general distributions.
Brenda J. Little - One of the best experts on this subject based on the ideXlab platform.
-
perspective on evidence for surface changes during ennoblement of type 316l stainless steel dissolved oxygen and capacitance measurements w h dickinson z Lewandowski r d geer corrosion 52 12 1996 p 910 920
Corrosion, 2019Co-Authors: Brenda J. LittleAbstract:Abstract:The pioneering work of Dickinson, et al., and other investigators in the Lewandowski research group at the Center for Biofilm Engineering, Montana State University, Bozeman, MT, provided a...
-
Perspective on “Evidence for Surface Changes During Ennoblement of Type 316L Stainless Steel: Dissolved Oxygen and Capacitance Measurements,” W.H. Dickinson, Z. Lewandowski, R.D. Geer, Corrosion 52, 12 (1996): p. 910-920
CORROSION, 2019Co-Authors: Brenda J. LittleAbstract:Abstract:The pioneering work of Dickinson, et al., and other investigators in the Lewandowski research group at the Center for Biofilm Engineering, Montana State University, Bozeman, MT, provided a...