1,721,189 research outputs found
On the closure in \overline M\sb g of smooth curves having a special Weierstrass point
Full text linkLet wt(2) be the closure in M̄g, the coarse moduli space of stable complex curves of genus g ≥ 3, of the locus in M̄g of curves possessing a Weierstrass point of weight at least 2. The class of wt(2) in the group Pic(M̄g) ⊗ Q is computed. The computation heavily relies on the notion of "derivative" of a relative Wronskian, introduced in [15] for families of smooth curves and here extended to suitable families of Deligne-Mumford stable curves. Such a computation provides, as a byproduct, a simpler proof of the main result proven in [6]
From linear recurrence relations to linear ODEs with constant coefficients
No full textLinear Ordinary Differential Equations (ODEs) with constant coefficients are studied by looking in general at linear recurrence relations in a module with coefficients in an arbitrary Z-algebra. The bridge relating the two theories is the notion of formal Laplace transform associated to a sequence of invertibles. From this more economical perspec- tive, generalized Wronskians associated to solutions of linear ODEs will be revisited, mentioning their relationships with Schubert Calculus for Grassmannians
Algebraic curves and differential equations: an Introduction
No full textAlgebraic Geometry has provided tools to study and solve several physical systems, and, conversely, the study of the famous “KP” PDE, has led to spectacular results in Algebraic Geometry.
In this paper we provide several example to show how such a pèhilosphy can be concretely implemented. In particular an exact solution of the Euler Rigid Body system is supplied
Jet bundles on Gorenstein curves and applications
Full text linkIn the last twenty years a number of papers appeared aiming to construct locally free replacements of the sheaf of principal parts for families of Gorenstein curves. The main goal of this survey is to present to the widest possible mathematical audience a catalogue of such constructions, discussing the related literature and reporting on a few applications to classical problems in Enumerative Algebraic Geometry
L'export manager: profilo, competenze e attività
No full textL'internazionalizzazione riveste un ruolo essenziale nelle strategie competitive e di sviluppo delle imprese. Tra le strategie di approccio ai mercati internazionali, l'esportazione rappresenta quella più consolidata e privilegiata, in particolare, dalle piccole e medie imprese. Il manuale di "Management dell'esportazione" propone questi temi, riconoscendo la loro rilevanza e l'elevato grado di vicinanza e di complementarietà a quelli delle strategie di ingresso e delle politiche di marketing internazionale. In questo concesto, sono identificatil profilo professionale dell'export manager, con le competenze e le attività associate al ruolo, in funzione del livello di internazionalizzazione raggiunto dalle impres
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Clifford semialgebras
Full text linkContinuing the theory of systems, we introduce a theory of Clifford semialgebra systems, with application to representation theory via Hasse-Schmidt derivations on exterior semialgebras. Our main result, after the construction of the Clifford semialgebra, is a formula describing the exterior semialgebra as a representation of the Clifford semialgebra, given by the endomorphisms of the first wedge power
- …
