Mechanics is the area of science concerned with the behavior of physical bodies when subjected to forces or displacements, and the subsequent effects of the bodies on their environment.

12840 Results for the subject "Mechanics":

AbstractFEniCS Mechanics is a Python package to facilitate computational mechanics simulations. The Python library dolfin, from the FEniCS Project, is used to formulate and numerically solve the problem in variational form. The general balance laws from continuum mechanics are used to enable rapid prototyping of different material laws. In addition to its generality, FEniCS Mechanics also checks the input provided by users to ensure that problem definitions are physically consistent. In turn, this code enables simulations of custom mechanics problems to be more accessible to those with limited programming or mechanics knowledge.

Miguel A. Rodriguez Publication date: 2019/01/01AbstractPhysics is the study of the motion of matter. It originates from Newtonian mechanics theory. In classical mechanics, which is established by Newton in the seventeenth century, particle dynamics was first employed to describe the motion of macroscopic objects. However, we must deal with continuously constructed media such as the earth, and the application of particle dynamics has some limitations. Thus, scientists developed continuum mechanics in the early twentieth century, including fluid mechanics and solid mechanics. Quantum mechanics has been developed in the same period to describe the motion of microscopic particles. The theory in this book is based on continuum mechanics and the methods of mathematical physics.

Wencai Yang Publication date: 2014/01/01AbstractSome reflections about open problems in statistical mechanics are offered on the occasion of the award of the IUPAP Boltzmann medal.

Elliott H. Lieb Publication date: 1999/02/01AbstractThe usual Newtonian mechanics in physical space may be contrasted with the mechanics in material space originated by Eshelby. Reciprocity relations within the linear theory of elasticity play a prominent role in the former. In this communication, two novel analogous theorems have been established in Eshelbian mechanics for linearly elastic bodies.

G. Herrmann Publication date: 2007/06/01AbstractBased on a general formulation for discrete-time quantum mechanics, introduced by M. Khorrami (Annals Phys.224(1995), 101), symmetries in discrete-time quantum mechanics are investigated. It is shown that any classical continuous symmetry leads to a conserved quantity in classical mechanics, as well as quantum mechanics. The transformed wave function, however, has the correct evolution if and only if the symmetry is nonanomalous.

M. Khorrami Publication date: 1996/12/15AbstractIn chemical engineering, fluid mechanics is a tool for the successful design of processes, which involve heat and mass transfer as well as chemical reactions. In order to exemplify this particular role of fluid mechanics, the implications of fluid mechanics on the heat transfer are demonstrated exemplarily.

O Molerus Publication date: 2000/03/01AbstractThe origins of the Journal of Fluid Mechanics, of which the first volume was published in 1956, are discussed, with reference to editorial correspondence during the early years of the Journal. This paper is based on a lecture given at the colloquium: A Century of Fluid Mechanics, 1870–1970, IMFT, Toulouse, France, 19–21 October 2016.

H. Keith Moffatt Publication date: 2017/07/01AbstractIn this paper, the Structural Mechanics network curriculum is designed to assist the classroom teaching. Based on Structural Mechanics network curriculum, the design thought, the design measure and the attention matters of network curriculum is introduced. In practice, using this Structural Mechanics network curriculum, the students learning initiative and interest are increased, and better teaching result is obtained.

Jianying Ren Publication date: 2012/01/01AbstractAn overview of fracture mechanics within the Research Division of a large international steel and engineering company is given. Fracture mechanics principles have been utilized to assess materials performance, structural integrity and component design. Examples are given of the applicability of these principles to steel making support activities and product usage in order to demonstrate the range and value of applications for fracture mechanics.

A.S. Blicblau Publication date: 1984/03/01Highlights•RPV fracture mechanics model based on RELAP5.•RPV fracture mechanics model based on CFD.•RPV fracture mechanics analysis.

V.F. González-Albuixech Publication date: 2016/02/01AbstractLudwig Prandtl (1875–1953) has been called the father of modern aerodynamics. His name is associated most famously with the boundary layer concept, but also with several other topics in 20th-century fluid mechanics, particularly turbulence (Prandtl's mixing length). Among his disciples are pioneers of modern fluid mechanics like Heinrich Blasius, Theodore von Kármán, and Walter Tollmien. Furthermore, Prandtl founded the Aerodynamische Versuchsanstalt (AVA) and the Kaiser-Wilhelm-Institut für Strömungsforschung in Göttingen, nuclei for the growth of fluid mechanics in Germany. In this article I trace this development on the basis of my recent biography of Prandtl.

Michael Eckert Publication date: 2017/07/01AbstractIn this paper we address the problem to give a concrete support to the idea, originally stemming from Niels Bohr, that quantum mechanics must be rooted inside the physics of macroscopic systems. It is shown that, starting from the formalism of the nonequilibrium statistical operator, which is now a consolidated part of quantum statistical mechanics, particular correlations between two isolated systems can be singled out and interpreted as microsystems. In this way also a new framework is established in which questions of decoherence can be naturally addressed.

L. Lanz Publication date: 2002/04/01AbstractIn this paper, we show how to avoid continuum concepts altogether for both Newtonian mechanics and for special relativistic mechanics. For Newtonian mechanics, we will establish all the usual conservation laws. For both Newtonian mechanics and for special relativistic mechanics, we will prove Galilean invariance for inertial systems. For easy comparison, discrete and continuous concepts will often be juxtaposed.

D. Greenspan Publication date: 2003/07/01AbstractWe propose a generalization of the standard geometric formulation of quantum mechanics, based on the classical Nambu dynamics of free Euler tops. This extended quantum mechanics has in lieu of the standard exponential time evolution, a nonlinear temporal evolution given by Jacobi elliptic functions. In the limit where latter's moduli parameters are set to zero, the usual geometric formulation of quantum mechanics, based on the Kahler structure of a complex projective Hilbert space, is recovered. We point out various novel features of this extended quantum mechanics, including its geometric aspects. Our approach sheds a new light on the problem of quantization of Nambu dynamics. Finally, we argue that the structure of this nonlinear quantum mechanics is natural from the point of view of string theory.

Djordje Minic Publication date: 2002/06/06AbstractThe correspondence principle asserts that quantum mechanics resembles classical mechanics in the high-quantum-number limit. In the past few years, many papers have been published on the extension of both quantum mechanics and classical mechanics into the complex domain. However, the question of whether complex quantum mechanics resembles complex classical mechanics at high energy has not yet been studied. This paper introduces the concept of a local quantum probability density ρ(z) in the complex plane. It is shown that there exist infinitely many complex contours C of infinite length on which ρ(z) dz is real and positive. Furthermore, the probability integral ∫Cρ(z)dz is finite. Demonstrating the existence of such contours is the essential element in establishing the correspondence between complex quantum and classical mechanics. The mathematics needed to analyze these contours is subtle and involves the use of asymptotics beyond all orders.

Carl M. Bender Publication date: 2010/11/01AbstractThe purpose of this paper is to cast doubt on the common allegation that quantum mechanics (QM) is incompatible with realism. I argue that the results usually considered inimical to realism, notably the violation of Bells inequality, in fact play the opposite role—they support realism. The argument is not intended, however, to demonstrate realism or refute its alternatives as general metaphysical positions. It is directed specifically at the view that QM differs from classical mechanics in that, unlike classical mechanics, it is not amenable to a realist interpretation.

Yemima Ben-Menahem Publication date: 1997/06/01Highlights•The dehydrogenation mechanism of 2,3-DDBPH and 2,3-DD-4,4′-DBPH by dehydrogenase BphB is investigated by QM/MM method.•The Boltzmann-weighted averaging method was employed to obtain potential barriers from five different snapshots.•Ser142, Asn143 and Lys159 are identified as key residues.

Ruiming Zhang Publication date: 2018/10/01AbstractContinuum mechanics is a subject that unifies solid mechanics, fluid mechanics, thermodynamics, and heat transfer, all of which are core subjects of mechanical engineering. The approach taken in this text is to use continuum mechanics as a universal tool in which to formulate the polymer mechanics theories that will be presented in the following chapters. In some undergraduate textbooks, the polymer mechanics frameworks are often presented using a traditional small-strain solid mechanics approach in an effort to make the theory less abstract. Here, a different approach is taken. Polymer components, due to their mechanical characteristics, are often both able and designed to undergo large deformations, and it is therefore important for the polymer mechanist to know that it is not sufficient to simply talk about stress and strain when working with polymers, but that there are in fact different types of stress and strain that can be used, and hence it is important to specify and c *Read more...*

Highlights•An elastic half-space subjected to surface tractions was semi analytically analyzed.•Gurtin and Murdoch's complete model of surface mechanics was taken into account.•Although extremely localized, the effects of surface mechanics are significant.•Proper design of surface properties can render desired displacements and stresses.•Surface mechanics introduces length scales into the classical Cerruti's problem.

Changwen Mi Publication date: 2017/09/01ABSTRACTOutlines of the history of development of fracture mechanics in Poland are given. Present state of research in this field is briefly characterized, names of scientists active in fracture mechanics, fields of their main interest and names of the corresponding scientific institutions are listed.

M. Sokolowski Publication date: 1983/01/01