4,798 research outputs found
Milnor open books and Milnor fillable contact 3-manifolds
We say that a contact manifold is Milnor fillable if it is contactomorphic to
the contact boundary of an isolated complex-analytic singularity (X,x).
Generalizing results of Milnor and Giroux, we associate to each holomorphic
function f defined on X, with isolated singularity at x, an open book which
supports the contact structure. Moreover, we prove that any 3-dimensional
oriented manifold admits at most one Milnor fillable contact structure up to
contactomorphism.
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In the first version of the paper, we showed that the open book associated to
f carries the contact structure only up to an isotopy. Here we drop this
restriction. Following a suggestion of Janos Kollar, we also give a simplified
proof of the algebro-geometrical theorem 4.1, central for the uniqueness
result.Comment: 17 page
The economic and social dimensions of Romania’s metallurgical industry
The purpose of this paper is to enhance the understanding of both the economic and social dimensions belonging to Romania’s metallurgical industry and how they contribute to generating business value. The approach of this subject became of utmost necessity in turbulent times such as the one Romania is facing nowadays
The relation productivity - environment in the context of sustainable development – case study on the Romanian industry
The purpose of this paper is to enhance the understanding of the relation between productivity and environment in the context of sustainable development, with a case study on the Romanian industry. The approach of this subject became of utmost necessity in turbulent times such as the one Romania is facing nowadays. Firstly, it provides a theoretical approach on sustainable development; secondly, it presents sustainable development as a key element in nations’ growth and thirdly, it emphasis the aspects concerning the relation productivity - environment in the context of sustainable development, with a case study on the Romanian industry
Braided Bialgebras of Type One
Braided bialgebras of type one in abelian braided monoidal categories are
characterized as braided graded bialgebras which are strongly
-graded both as an algebra and as a coalgebra
Strong normalization for System F by HOAS on top of FOAS
We present a point of view concerning HOAS (Higher-Order Abstract Syntax) and an extensive exercise in HOAS along this point of view. The point of view is that HOAS can be soundly and fruitfully regarded as a definitional extension on top of FOAS (First-Order Abstract Syntax). As such, HOAS is not only an encoding technique, but also a higher-order view of a first-order reality. A rich collection of concepts and proof principles is developed inside the standard mathematical universe to give technical life to this point of view. The exercise consists of a new proof of Strong Normalization for System F. The concepts and results presented here have been formalized in the theorem prover Isabelle/HOL
ECONOMIC EVALUATION OF A BREEDING PROGRAMME FOR SETTING UP TWO HIGH PERFORMANCES BEE LINES
This study aimed to evaluate costs, incomes and financial results related to the creation of two Apis Mellifica Carpatica lines, based on a specific Breeding Programme within a closed population. The two beelines have been carefully selected for the bee populations living in two areas of Romania: North Moldavia and South Muntenia. A new selection technology is set up in order to produce high performance queen bees, well adapted to the environmental conditions mainly to picking. Genetic gain will be get by selling the mated selected queens belonging to the two lines to various beekeepers interested to obtain more and high quality bee products
Dust effects on the derived Sersic indexes of disks and bulges in spiral galaxies
We present a theoretical study that quantifies the effect of dust on the
derived Sersic indexes of disks and bulges. The changes in the derived
parameters from their intrinsic values (as seen in the absence of dust) were
obtained by fitting Sersic distributions on simulated images of disks and
bulges produced using radiative transfer calculations and the model of Popescu
et al. 2011. We found that dust has the effect of lowering the measured Sersic
index in most cases, with stronger effects for disks and bulges seen through
more optically thick lines of sight.Comment: 3 pages, 2 figures, to appear in the Proceedings of the IAU Symposium
No.284, "The Spectral Energy Distribution of Galaxies", 5-9 sept. 2011,
editors Richard J. Tuffs and Cristina C. Popesc
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