Results 221 to 230 of about 46,964 (266)

The association of fractional cover, foliage projective cover and biodiversity with birthweight

Science of The Total Environment, 2021
Environmental exposures can contribute both benefits and risks to human health. Maternal exposure to green space has been associated with improvements in birthweight, among other birth outcomes. Newer measures of green space have been developed, which allows for an exploration of the effect of different ground covers (green, dry and bare earth), as ...
Vilcins, Dwan, Scarth, Peter, Sly, Peter D., Jagals, Paul, Knibbs, Luke, Baker, Peter   +5 more
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Codivisible and Projective Covers

Communications in Algebra, 1974
This paper continues the study of codivisible modules, whose definition is a “dualization” of Lambek's concept [4] of a divisible module relative to a torsion theory. The main purpose of this work is to give a solution to the following problem posed by Bland [2]: “It would be interesting to know under what conditions the universal existence of ...
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Topological Extension Properties and Projective Covers

Canadian Journal of Mathematics, 1982
Introduction. All spaces considered in this paper are assumed to be (Hausdorff) completely regular, and all maps are continuous. Let be a topological property of spaces. We shall identify with the class of spaces having . A space having is called a -space, and a subspace of a -space is called a -regular space. The class of -regular spaces is denoted
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Enumeration of Concrete Regular Covering Projections

SIAM Journal on Discrete Mathematics, 1995
Polya's and de Brujin's enumerative methods and the Möbius inversion are employed to derive a formula for counting the isomorphism classes of regular covering projections of a graph.
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Knot Projections and Knot Coverings

1993
In this paper, computer programs are given which draw knot diagrams, knot projections and representations of knot groups into the symmetric group of degree n.
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Projective Planes, Coverings and a Network Problem

Designs, Codes and Cryptography, 2003
This article studies a problem concerning packet switched networks which can be translated into a combinatorial design problem involving \(k\)-arcs in projective planes, 3-dimensional linear codes, the theory of fractional matchings and designs which approximate projective planes. The combinatorial design problem concerns coverings \(C(n,k,r)\).
Bierbrauer J., MARCUGINI, Stefano, PAMBIANCO, Fernanda   +2 more
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On Analytic Coverings of Weighted Projective Spaces

Bulletin of the London Mathematical Society, 1985
We classify the analytic coverings of a weighted projective space \(P=P(Q)\) whose branching sets are unions of the form \(P_{\sin g}\cup H\), where \(P_{\sin g}\) denotes the singular part of P and H is a normal hypersurface in P. It turns out that all such coverings are cyclic and their total spaces are hypersurfaces in suitable weighted projective ...
Dimca, Alexandru, Dimiev, Stancho
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Covering groups and projective representations

1992
In order to deduce Theorem 1.18 from the special case established in the last chapter, we will need to exploit a relationship between characters of tori in G and representations of G. This relationship is most natural when it is formulated in terms of certain coverings of the tori related to “ρ-shifts” for G (see for example Theorem 1.37 or Theorem 6.8
Jeffrey Adams, Dan Barbasch, David A. Vogan   +2 more
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Rings Whose Nonsingular Modules Have Projective Covers

Ukrainian Mathematical Journal, 2016
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Asgari, Sh., Haghany, A.
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Projective Groups and Frattini Covers

1986
The absolute Galois group of a PAC field is projective (Theorem 10.17). This chapter includes a converse (Corollary 20.16): If G is a projective group, then there exists a PAC field K such that G (K) ≅ G. Projective groups also appear as the universal Frattini covers of profinite groups (Proposition 20.33).
Michael D. Fried, Moshe Jarden
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