Adding to the paradox: the accelerated twin is olderWe discuss a rather surprising version of the twin paradox in which (contrary to the familiar classical version) the twin who accelerates is older on the reunion than his never accelerating brother.M. A. Abramowicz, S. Bajtlik·May 14, 2009SaveLearn
Force and moment balance equations for geometric variational problems on curvesWe consider geometric variational problems for a functional defined on a curve in three-dimensional space. The functional is assumed to be written in a form invariant under the group of Euclidean…E. L. Starostin, G. H. M. van der Heijden·May 12, 2009SaveLearn
About the temperature of moving bodiesRelativistic thermodynamics is constructed from the point of view of special relativistic hydrodynamics. A relativistic four-current for heat and a general treatment of thermal equilibrium between…T. S. Biró, P. Ván·May 11, 2009SaveLearn
Analysis of the railway heave induced by soil swelling at a site in southern FranceIn order to better understand the heave observed on the railway roadbed of the French high-speed train (TGV) at Chabrillan in southern France, the swelling behaviour of the involved expansive clayey…Anh-Minh Tang, Yu-Jun Cui, Viet-Nam Trinh et al.·May 6, 2009SaveLearn
Computational Methodology for the Prediction of Functional Requirement Variations Across the Product Life-CycleThe great majority of engineered products are subject to thermo-mechanical loads which vary with the product environment during the various phases of its life-cycle (machining, assembly, intended…Guillaume Mandil, Alain Desrochers, Alain Rivière·May 6, 2009SaveLearn
Self-gravitating astrophysical mass with singular central density vibrating in fundamental modeThe fluid-dynamical model of a self-gravitating mass of viscous liquid with singular density at the center vibrating in fundamental mode is considered in juxtaposition with that for Kelvin…S. I. Bastrukov, H. -K. Chang, E. -H. Wu et al.·May 4, 2009SaveLearn
Angular Momentum of Electromagnetic Radiation. Fundamental physics applied to the radio domain for innovative studies of space and development of new concepts in wireless communicationsIn this diploma thesis we study the characteristics of electromagnetic fields carrying orbital angular momentum (OAM) by analyzing and utilizing results achieved in optics and then apply them to the…Johan Sjöholm, Kristoffer Palmer·May 2, 2009SaveLearn
Equilibrium Charge Density on a Thin Curved WireThis work addresses the electrostatic problem of a thin, curved, cylindrical conductor, or a conducting filament, and shows that the corresponding linear charge density slowly tends to uniformity as…M. H. Partovi, J. D. Griffiths·Apr 28, 2009SaveLearn
Interaction with thermal radiation in the free expansion and mixing of ideal gases and Gibbs' paradox in classical thermodynamicsThe standard theory of ideal gases ignores the interaction of the gas particles with the thermal radiation (photon gas) that fills the otherwise vacuum space between them. This is an unphysical…A. Paglietti·Apr 26, 2009SaveLearn
Finite Element Modelling of Micro-cantilevers Used as Chemical SensorsNowadays, silicon micro-cantilevers with different geometrical shapes are widely used as micro-electro-mechanical systems and, more recently, as force sensor probes in atomic force microscopy (AFM).…Guy Louarn, Stéphane Cuenot·Apr 25, 2009SaveLearn
Investigating the time-dependent behaviour of Boom clay under thermo-mechanical loadingAmong the various laboratory studies to investigate the Thermo-Hydro-Mechanical (THM) behaviour of Boom clay, relatively few were devoted to the time dependent behaviour, limiting any relevant…Yu-Jun Cui, Trung Tinh Le, Anh-Minh Tang et al.·Apr 23, 2009SaveLearn
Modelling the thermo-mechanical volume change behaviour of compacted expansive claysCompacted expansive clays are often considered as a possible buffer material in high-level deep radioactive waste disposals. After the installation of waste canisters, the engineered clay barriers…Anh-Minh Tang, Yu-Jun Cui·Apr 23, 2009SaveLearn
Exponential cosmological redshift in a linearly expanding universeThe first principles analysis of the radiation by an arbitrary source in a flat Friedmann-Robertson-Walker space-time is presented. The obtained analytical solution explicitly shows that the…Neil V. Budko·Apr 21, 2009SaveLearn
Electromagnetic Boundary Conditions Defined in Terms of Normal Field ComponentsA set of four scalar conditions involving normal components of the fields D and B and their normal derivatives at a planar surface is introduced, among which different pairs can be chosen to…I. V. Lindell, A. H. Sihvola·Apr 20, 2009SaveLearn
Synchronization of Sound SourcesSound generation and -interaction is highly complex, nonlinear and self-organized. Already 150 years ago Lord Rayleigh raised the following problem: Two nearby organ pipes of different fundamental…Markus Abel, Karsten Ahnert, Steffen Bergweiler·Apr 16, 2009SaveLearn
Comment on "Dynamics of a Charged Particle" by F. Rohrlich [Phys. Rev. E 77, 046609 (2008), arXiv:0804.4614]The equation derived by F. Rohrlich (Phys. Rev. E 77, 046609 (2008)) has been known for 60 years (C. J. Eliezer, Proc. Royal Soc. London. Ser. A 194, 543 (1948)). For a long time this equation has…N. M. Naumova, I. V. Sokolov·Apr 15, 2009SaveLearn
Quantum action, non-locality and coherence from classical perception, a new facet of Lagrangian formalism for relativistic dynamicsClassical and quantum mechanical descriptions of physical world are seamlessly abridged within the framework of Lagrangian formalism which, besides revealing the essence of nonlocally correlated…D Das·Apr 14, 2009SaveLearn
Why Jefimenko equations ? (A comment on "Multipole radiation fields from the Jefimenko equation...", by R. de Melo e Souza et al, Am. J. Phys. 77 (1), 67-72 (2009), arXiv:0812.4679)In this comment, we discuss some features of the multipolar expansion of the power radiated by a confined system of charges and currents, and the possibility of generalization to a higher arbitrary…C. Vrejoiu, R. Zus·Apr 13, 2009SaveLearn
Babinet's principle in the Fresnel regime studied using ultrasoundThe diffraction of ultrasound by a circular disk and an aperture of the same size have been investigated as a demonstration of Babinet's principle in the Fresnel regime. The amplitude and the…Akira Hitachi, Momo Takata·Apr 8, 2009SaveLearn
Optimisation of tool axis orientation in 5 axis machining taking into account kinematical constraintsAfter presenting the main difficulties related to machining 5 axes machining within the context of HSM, we present a surface model of 5-axis trajectories allowing taking into account geometrical and…Sylvain Lavernhe, Christophe Tournier, Claire Lartigue·Apr 7, 2009SaveLearn
Model for performance prediction in multi-axis machiningThis paper deals with a predictive model of kinematical performance in 5-axis milling within the context of High Speed Machining. Indeed, 5-axis high speed milling makes it possible to improve…Sylvain Lavernhe, Christophe Tournier, Claire Lartigue·Apr 7, 2009SaveLearn
Semi-analytical model of acoustic-wave generation by a laser line pulse in an optically absorptive isotropic cylinderSemi-analytical model for calculating acoustic response to a line-focused laser pulse in an optically absorptive isotropic cylinder is proposed and implemented. It is assumed that the laser input is…D. Segur, A. L. Shuvalov, Y. Pan et al.·Apr 4, 2009SaveLearn
The Gaussian formula and spherical aberration of the static and moving curved mirrors from Fermat's principleThe Gaussian formula and spherical aberrations of the static and relativistic curved mirrors are analyzed using the optical path length (OPL) and Fermat's principle. The geometrical figures…Sylvia H. Sutanto, Paulus C. Tjiang·Apr 2, 2009SaveLearn
Dynamics of Emitting Electrons in Strong Electromagnetic FieldsWe derive a modified non-perturbative Lorentz-Abraham-Dirac equation. It satisfies the proper conservation laws, particularly, it conserves the generalized momentum, the latter property eliminates…Igor V. Sokolov, Natalia M. Naumova, John A. Nees et al.·Apr 2, 2009SaveLearn
Similarity Flow Solutions of a Non-Newtonian Power-law FluidIn this paper we present a mathematical analysis for a steady-state laminar boundary layer flow, governed by the Ostwald-de Wael power-law model of an incompressible non- Newtonian fluid past a…Mohamed Guedda, Zakia Hammouch·Apr 2, 2009SaveLearn