Results 91 to 100 of about 3,729,724 (366)

Approximating chromatic sum coloring of bipartite graphs in expected polynomial time

open access: yesТруды Института системного программирования РАН, 2018
It is known that if P≠NP the sum coloring problem cannot be approximated within for some constant . We propose for arbitrary small an approximation scheme for this problem that works in expected polynomial time.
A. S. Asratian, N. N. Kuzyurin
doaj   +1 more source

Chiral Acoustic Phonon and Conservation of Pseudoangular Momentum in α‐Quartz

open access: yesAdvanced Materials, EarlyView.
Chiral acoustic phonons in α‐quartz are probed via Brillouin light scattering, exploiting the photon's helicity and the crystal's handedness. The interaction obeys a selection rule arising from pseudoangular momentum conservation, enabling direct optical access to phonon chirality in nonsymmorphic crystals.
Changsoo Kim   +8 more
wiley   +1 more source

About some exponential inequalities related to the sinc function

open access: yesJournal of Inequalities and Applications, 2018
In this paper, we prove some exponential inequalities involving the sinc function. We analyze and prove inequalities with constant exponents and inequalities with certain polynomial exponents. Also, we establish intervals in which these inequalities hold.
Marija Rašajski   +2 more
doaj   +1 more source

Asymmetry of the Ferroelectric Phase Transition in BaTiO3

open access: yesAdvanced Materials, EarlyView.
Phase transitions are typically assumed to behave identically in forward and reverse. This work shows that in the ferroelectric material barium titanate this is not true: heating drives an abrupt, first‐order jump, while cooling gives a smooth, continuous change.
Asaf Hershkovitz   +14 more
wiley   +1 more source

On the degree of the polynomial defining a planar algebraic curves of constant width

open access: yes, 2013
In this paper, we consider a family of closed planar algebraic curves $\mathcal{C}$ which are given in parametrization form via a trigonometric polynomial $p$.
Bardet, Magali, Bayen, Térence
core   +1 more source

Conformal Oscillator Representations of Orthogonal Lie Algebras [PDF]

open access: yes, 2014
The conformal transformations with respect to the metric defining the orthogonal Lie algebra o(n) give rise to a one-parameter (c) family of inhomogeneous first-order differential operator representations of the orthogonal Lie algebra o(n+2).
Xu, Xiaoping
core  

Operando X‐ray Spectroscopy Study of Pd and Pd–Au Laterally Condensed Catalysts during Selective Acetylene Hydrogenation: The Role of Carbon

open access: yesAdvanced Materials, EarlyView.
The selective hydrogenation of acetylene over laterally condensed Pd and Pd–Au catalysts (LCCs) was investigated using operando X‐ray absorption and photoelectron spectroscopy in combination with density functional theory. Pd‐LCCs were found to incorporate significantly more carbon into the metal lattice than Pd–Au LCCs, where the carbon uptake governs
Eylül Öztuna   +22 more
wiley   +1 more source

Trigonometric polynomial solutions of equivariant trigonometric polynomial Abel differential equations

open access: yesElectronic Journal of Differential Equations, 2017
Let $A(\theta)$ non-constant and $B_j(\theta)$ for $j=0,1,2,3$ be real trigonometric polynomials of degree at most $\eta \ge 1$ in the variable x. Then the real equivariant trigonometric polynomial Abel differential equations $A(\theta) y' =B_1(\theta)
Claudia Valls
doaj  

On some constants in simultaneous approximation

open access: yesInternational Journal of Mathematics and Mathematical Sciences, 1995
Pointwise estimates for the error which is feasible in simultaneous approximation of a function and its derivatives by an algebraic polynomial were originally pursued from theoretical motivations, which did not immediately require the estimation of the ...
K. Balázs, T. Kilgore
doaj   +1 more source

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