1,375 research outputs found
Vanishing ideals over graphs and even cycles
Let X be an algebraic toric set in a projective space over a finite field. We
study the vanishing ideal, I(X), of X and show some useful degree bounds for a
minimal set of generators of I(X). We give an explicit description of a set of
generators of I(X), when X is the algebraic toric set associated to an even
cycle or to a connected bipartite graph with pairwise disjoint even cycles. In
this case, a fomula for the regularity of I(X) is given. We show an upper bound
for this invariant, when X is associated to a (not necessarily connected)
bipartite graph. The upper bound is sharp if the graph is connected. We are
able to show a formula for the length of the parameterized linear code
associated with any graph, in terms of the number of bipartite and
non-bipartite components
Regularity and algebraic properties of certain lattice ideals
We study the regularity and the algebraic properties of certain lattice
ideals. We establish a map I --> I\~ between the family of graded lattice
ideals in an N-graded polynomial ring over a field K and the family of graded
lattice ideals in a polynomial ring with the standard grading. This map is
shown to preserve the complete intersection property and the regularity of I
but not the degree. We relate the Hilbert series and the generators of I and
I\~. If dim(I)=1, we relate the degrees of I and I\~. It is shown that the
regularity of certain lattice ideals is additive in a certain sense. Then, we
give some applications. For finite fields, we give a formula for the regularity
of the vanishing ideal of a degenerate torus in terms of the Frobenius number
of a semigroup. We construct vanishing ideals, over finite fields, with
prescribed regularity and degree of a certain type. Let X be a subset of a
projective space over a field K. It is shown that the vanishing ideal of X is a
lattice ideal of dimension 1 if and only if X is a finite subgroup of a
projective torus. For finite fields, it is shown that X is a subgroup of a
projective torus if and only if X is parameterized by monomials. We express the
regularity of the vanishing ideal over a bipartie graph in terms of the
regularities of the vanishing ideals of the blocks of the graph.Comment: Bull. Braz. Math. Soc. (N.S.), to appea
New Pact for Europe - National Report - PORTUGAL. EPC Project Report, October 2017
This is the seventh in a series of National Reports to be published as part of the new phase of the New Pact for Europe project.* According to the Portuguese NPE Reflection Group, the EU has shown a lot of resilience in the past few years when it had to deal with a multitude of crises, but it also warns of the dangers of being complacent. The EU is still facing several identity, legitimacy and institutional challenges, which are very complex and multi-dimensional
Country branding and foreign investment location : the case of Portugal
Mestrado em MarketingNation branding is not a new concept. It has been researched, discussed and applied
in some cases with success. Neither the concept is a consensual issue nor its practice;
however, the pressures felt by countries in today's globalized world have been
pushing governments, public and private entities, and citizens to take a more active
role in managing their country branding. Branding and marketing techniques usually
adopted by companies are now used by countries to compete with each other in the
attraction of tourists, talented people, exports and investors.
The purpose of this study is to contribute to the understanding of the relevance of
nation branding concept from a corporate perspective and to introduce a less
researched issue: the role of national image in investment decisions. Over 500
corporate decision-makers in the largest foreign companies operating in Portugal
were surveyed. To accomplish our purposes, the personification marketing tool was
used through the Corporate Character Scale developed by Davies et al., as well as a
23-item list of determinants for investment location choice, derived from literature
review.
Findings revealed a positive relation between the country's image and the overall
image of the country as an investment location. We also observed that the country
image explains around 40% for the option of Portugal as an investment location.
Finally, limitations of the study and suggestions for future investigations can be
found in this paper.info:eu-repo/semantics/publishedVersio
Part I : Comparing derivatization methods for amino acids – one and two-step procedures using gas chromatography – flame ion detector (GC-FID) Part II: Story of an icon from its execution until its conservation
Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de
Lisboa para obtenção do grau de Mestre em Conservação e RestauroTwo derivatization methods were tested in twenty-one standard amino acids (AAs) for further identification and quantification by the analytical technique of Gas Chromatography with Flame Ion Detector (GC-FID). For the one-step derivatization reaction N-methyl-N (tert.- butyldimethylsilyl)trifluoroacetamide (MTBSTFA) was used and for the two-step reaction we used hydrochloridic acid (HCl) and trifluoroacetic anhydride (TFAA).
We obtained better results with the derivatization procedure in two-steps, although it takes longer, and we concluded that the reproducibility of these reactions is difficult to achieve
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