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Mapping degrees of self-maps of simply-connected manifolds  [PDF]
Manuel Amann
Mathematics , 2011,
Abstract: An oriented compact closed manifold is called inflexible if the set of mapping degrees ranging over all continuous self-maps is finite. Inflexible manifolds have become of importance in the theory of functorial semi-norms on homology. Although inflexibility should be a generic property in large dimensions, not many simply-connected examples are known. We show that from a certain dimension on there are infinitely many inflexible manifolds in each dimension. Besides, we prove flexibility for large classes of manifolds and, in particular, as a spin-off, for homogeneous spaces. This is an outcome of a lifting result which also permits to generalise a conjecture of Copeland--Shar to the "real world". Moreover, we then provide examples of simply-connected smooth compact closed manifolds in each dimension from dimension 70 on which have the following properties: They do not admit any self-map which reverses orientation. (For this we consider the lack of orientation reversal in the strongest sense possible, i.e. we prove the non-existence of any self-map of arbitrary negative mapping degree.) Moreover, the manifolds neither split as non-trivial Cartesian products nor as non-trivial connected sums.
Algebraic degrees for iterates of meromorphic self-maps of $?^k$  [PDF]
Viet-Anh Nguyen
Mathematics , 2006,
Abstract: We first introduce the class of quasi-algebraically stable meromorphic maps of $\P^k.$ This class is strictly larger than that of algebraically stable meromorphic self-maps of $\P^k.$ Then we prove that all maps in the new class enjoy a recurrent property. In particular, the algebraic degrees for iterates of these maps can be computed and their first dynamical degrees are always algebraic integers.
GROWING SELF ORGANIZED MAPS FOR RADIOGRAPHIC NON DESTRUCTIVE TESTING OF METALLIC PRODUCTS  [PDF]
Sarin CR,Manu R Krishnan
International Journal of Soft Computing & Engineering , 2012,
Abstract: Manual inspection of metallic products can only be atime-consuming and is less reliable to find microscopic andinternal defects, therefore is an expensive task; it can also sufferfrom operator performance. The proposed system apply imageprocessing techniques to automatically inspect radiographicimages and evaluate the data to find faults and is based onImproved Growing Self organized Maps Segmentation. Thenumber of false detections is still high and will be addressed infuture research. Monitoring the defect or damage at an early stageis a very important as it allows to implement operations to classifyand correct defects and improves the safety, reliability, accuracy,and high throughput of the structure. This paper presents animproved intelligent methodology for Radiographic automatedvisual quality inspection and, which provides many advantagesover traditional methods. The accuracy of conventional systems isvery much depending on the selected features, which are extractedfrom defect images. Growing Self Organized Maps forRadiographic Non Destructive Testing is an advanced methodsuitable for crack detection, which gives a smoothed image toobtain uniform brightness, followed by removing isolated points toremove noise and morphological operations with fast operation.
Dynamical Degrees, Arithmetic Degrees, and Canonical Heights for Dominant Rational Self-Maps of Projective Space  [PDF]
Joseph H. Silverman
Mathematics , 2011,
Abstract: Let F : P^N --> P^N be a dominant rational map. The dynamical degree of F is the quantity d_F = lim (deg F^n)^(1/n). When F is defined over a number field, we define the arithmetic degree of an algebraic point P to be a_F(P) = limsup h(F^n(P))^(1/n) and the canonical height of P to be h_F(P) = limsup h(F^n(P))/n^k d_F^n for an appropriately chosen integer k = k_F. In this article we prove some elementary relations and make some deep conjectures relating d_F, a_F(P), and h_F(P). We prove our conjectures for monomial maps.
Self-mapping Degrees of 3-Manifolds  [PDF]
Hongbin Sun,Shicheng Wang,Jianchun Wu,Hao Zheng
Mathematics , 2008,
Abstract: For each closed oriented 3-manifold $M$ in Thurston's picture, the set of degrees of self-maps on $M$ is given.
Quantization of linear Poisson structures and degrees of maps  [PDF]
Michael Polyak
Physics , 2002, DOI: 10.1023/B:MATH.0000017675.20434.79
Abstract: Kontsevich's formula for a deformation quantization of Poisson structures involves a Feynman series of graphs, with the weights given by some complicated integrals (using certain pullbacks of the standard angle form on a circe). We explain the geometric meaning of this series as degrees of maps of some grand configuration spaces; the associativity proof is also interpreted in purely homological terms. An interpretation in terms of degrees of maps shows that any other 1-form on the circle also leads to a *-product and allows one to compare these products.
Self cup products and the theta characteristic torsor  [PDF]
Bjorn Poonen,Eric Rains
Mathematics , 2011,
Abstract: We give a general formula relating self cup products in cohomology to connecting maps in nonabelian cohomology, and apply it to obtain a formula for the self cup product associated to the Weil pairing.
Maps preserving the spectrum of certain products of operators  [PDF]
Ali Taghavi,Roja Hosseinzadeh
Mathematics , 2013,
Abstract: Let H be a complex Hilbert space, B(H) and S(H) be the spaces of all bounded operators and all self-adjoint operators on H, respectively. We give the concrete forms of the maps on B(H) and also S(H) which preserve the spectrum of certain products of operators.
Orbits for products of maps  [PDF]
Apisit Pakapongpun,Thomas Ward
Mathematics , 2010,
Abstract: We study the behaviour of the dynamical zeta function and the orbit Dirichlet series for products of maps. The behaviour under products of the radius of convergence for the zeta function, and the abscissa of convergence for the orbit Dirichlet series, are discussed. The orbit Dirichlet series of the cartesian cube of a map with one orbit of each length is shown to have a natural boundary.
Pulling Back Cohomology Classes and Dynamical Degrees Of Monomial Maps  [PDF]
Jan-Li Lin
Mathematics , 2010,
Abstract: We study the pullback maps on cohomology groups for equivariant rational maps (i.e., monomial maps) on toric varieties. Our method is based on the intersection theory on toric varieties. We use the method to determine the dynamical degrees of monomial maps and compute the degrees of the Cremona involution.
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