Results 221 to 230 of about 10,185 (266)

Structural stability of rhenium as a function of lattice compression: Theory

Physical Review B, 1988
Total-energy, linearized augmented Slater-type orbital calculations have been done for rhenium as a function of lattice volume in response to recent experiments addressing the issue of whether the hcp phase of Re becomes unstable, with respect to the bcc phase, at high pressures.
, Watson, , Davenport, , Weinert, , Fernando   +3 more
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A lattice theory approach to the structure of mental models

Philosophical Transactions of the Royal Society of London. B, Biological Sciences, 1990
Abstract Lattice theory is proposed to provide a formalism for the knowledge base used as a mental model by the operator of a complex system. The ordering relation ‘>’ is interpreted as ‘is caused by’, and the lattice becomes a representation of the operator’s causal hypotheses about the system. A given system can be thought of
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Classical solutions and the vacuum structure in lattice gauge theories

Nuclear Physics B - Proceedings Supplements, 2000
Classical solutions corresponding to monopole-antimonopole pairs are found in 3d and 4d SU(2) and U(1) lattice gauge theories. The stability of these solutions in different theories is studied.
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Lattice theory of fracture of solids with layered structure

Journal of Applied Physics, 1988
The lattice trapping effect of a crack in solids with layered structure has been studied with a double-chain model. It is shown that the difference in physicomechanical properties between different atomic planes has significant influence upon this effect, and the stress range for stability of a crack can be enhanced by increasing the difference.
Decheng Tian, Yin-Hua Xu, Guo-Ming Li, Wei-Ho Guan   +3 more
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Structure and Decomposition Theory of Lattices

1990
One of the most natural problems which arise in the investigation of an abstract algebraic system is that of representing the elements of the system in terms of a canonical subset by means of the operations of the system. Thus for a polynomial domain over a field with the operation that of ordinary polynomial multiplication it is the problem of ...
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The phase structure of lattice Yang-Mills theories

Il Nuovo Cimento B, 1989
A recently proposed general mechanism for the occurrence of phase transitions is investigated in the context of lattice gauge theories. It leads to the prediction that all zero-temperature lattice gauge theories inD≥3 must undergo a phase transition; it is the limit of the finite temperature deconfining transition.
A. Patrascioiu, E. Seiler, V. Linke, I. O. Stamatescu   +3 more
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Structural diversity in the lattice of equational theories

Algebra Universalis, 1981
This paper is principally concerned with conditions under which various partition lattices are isomorphic to intervals in either the lattice of equational theories extending a given equational theory or the lattice of subtheories of a given equational theory.
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On the Structure of the Phases in Lattice Gauge Theories

1980
In recent years a lot of work has been concentrated on the study of non-abelian gauge theories on a lattice 1. The introduction of a lattice is crucial do define the theory in a non-perturbative way: in lattice gauge theories it is possible to use strong coupling techniques such as the high temperature expansion 2, the numerical simulations based on ...
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Truncated Distributive Lattices: Conceptual Structures of Simple-Implicational Theories

Order, 2003
A truncated distributive lattice is a lattice \(L\) with 0 such that there is a distributive lattice \(D\) in which \(L\setminus\{0\}\) is a proper order filter. A simple-implicational theory is a triple \(\mathcal{T}=(M,R,\mathcal{A})\), where \(M\) is a non-empty set, \(R\) is a binary relation on \(M\), and \(\mathcal{A}\) is a set of subsets of \(M\
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A lattice theory of morphic effects in crystals of the diamond structure

Annals of Physics, 1970
Abstract A microscopic theory of the electric field induced infrared absorption by crystals of the diamond structure is presented in this paper, together with a determination of the modifications in the first-order Raman spectra of such crystals induced by externally applied electric fields and stresses.
S Ganesan, A.A Maradudin, J Oitmaa
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