Results 301 to 310 of about 1,387,416 (334)

Magnetic order in the periodic Anderson model

Physical Review B, 1993
We study the ground state of the symmetric, finite-U, periodic Anderson model using a mean-field slave-boson theory of the Kotliar-Ruckenstein type. At half filling (two electrons per site) we find a charge gap at all U>0 and a transition from the paramagnetic to an antiferromagnetically ordered (AF) state at a critical value of the on-site interaction
Peter Wölfle, B Möller
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Interpenetrating Nets: Ordered, Periodic Entanglement

Angewandte Chemie International Edition, 1998
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Richard Robson, Stuart Robert Batten
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Confirmation Theory, Order, and Periodicity

Philosophy of Science, 1963
This paper examines problems of order and periodicity which arise when the attempt is made to define a confirmation function for a language containing elementary number theory as applied to a universe in which the individuals are considered to be arranged in some fixed order.
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First order periodic problems [PDF]

, 1997
This chapter discusses the nonlinear first order differential equation $$\left\{ {\begin{array}{*{20}{c}} {y' = f\left( {t,y} \right){\text{ a}}{\text{.e}}{\text{. on }}\left[ {0,T} \right]} \\ {y\left( 0 \right) = y\left( T \right)} \end{array}} \right.$$ (1.1) where f: [0,T] × R → R is a L 1-Caratheodory function (see definition 3.2).
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DETECTION OF PERIODICITIES BY HIGHER‐ORDER CROSSINGS

Journal of Time Series Analysis, 1987
Abstract. The axis‐crossing counts in a time series and in its successive differences are called higher‐order crossings (HOC). Under the Gaussian assumption the sequence of expected HOC is monotone increasing and admits a spectral representation which establishes a clear connection between HOC and the spectrum.
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Lower estimates of the order of maximal periodic groups of prime period

Mathematical Notes of the Academy of Sciences of the USSR, 1988
The authors obtain lower bounds for the order and the nilpotency class of \(\bar B(2,p)\)- the largest 2-generator finite group of prime exponent p (such a group exists via Kostrikin's positive solution of the restricted Burnside problem for groups of prime exponent.
N. N. Repin, S. I. Adyan
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On the Long-Period Ordered Alloys

1974
Studies of the long-period ordered alloys are surveyed. Alloys that are in most cases f.c.c. in a disordered state often transform into that ordered state composed of regular antiphase domains which is represented by CuAuII but realized in many A3B type alloys such as Ag3Mg, Cu3 Pt II, Pd3Mn, Au3Cd, Au3Zn(H), Au3+Zn, Au3Mn, Cu3Pd(α″) etc.
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Periodic Extensions of Ordered Groups

1989
A PARTIAL ORDER P on a group G is a subset P of G satisfying the following conditions: (i) PP = 1 (ii) P ∩ P -1 = 1 and (iii) Pg = gP for all g in G.
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Quasicrystals: From Periodic to Non-Periodic Order in Solids [PDF]

, 1988
Experiments on metal alloys as A14 Mn since 1984 enforce the concept of non-periodic long-range order in condensed matter. Theoretical principles for this order are formulated. Orientational order with non-crystallographic point symmetry can be obtained by lifting the symmetry group from E 3 to E n , n > 3.
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A tradeoff between period and order of linear periodic stabilizing compensators

Automatica, 1996
The problem of stabilizing a discrete-time linear time-invariant plant by a linear periodic compensator is considered. It is shown that it is possible to trade off compensator order for an increased period. Also, it is shown that first-order linear periodic controllers can be used to solve the strong and simultaneous stabilization problems.
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