A characterization of some families of Cohen--Macaulay, Gorenstein and/or Buchsbaum rings

We provide algorithmic methods to check the Cohen--Macaulayness, Buchsbaumness and/or Gorensteiness of some families of semigroup rings that are constructed from the dilation of bounded convex polyhedrons of $\R^3_{\geq}$. Some families of semigroup rings are given satifying these properties

Energy-Entropy-Momentum integration of discrete thermo-visco-elastic dynamics.

A novel time integration scheme is presented for the numerical solution of the dynamics of discrete systems consisting of point masses and thermo-visco-elastic springs. Even considering fully coupled constitutive laws for the elements, the obtained solutions strictly preserve the two laws of thermo dynamics and the symmetries of the continuum evolution equations. Moreover, the unconditional control over the energy and the entropy growth have the effect of stabilizing the numerical solution, allowing the use of larger time steps than those suitable for comparable implicit algorithms. Proofs for these claims are provided in the article as well as numerical examples that illustrate the performance of the method

Public sector wage gaps in Spanish regions.

This paper provides an approximation to the measurement of public sector wage gaps in Spanish regions. By using data from the European Community Household Panel, it is shown that the balance between what private firms pay in the local market and what the public sector pays, differs substantially in different areas of the country. Public sector wage differences among Spanish regions are mostly due to differences in returns, not to differences in characteristics or to selection effects, and are not constant across gender, educational levels, or occupations. Moreover, in those regions where Regional Governments have a higher weight in public employment, public wage gaps are higher and public employers pay higher returns. There also seems to be a cross-regional positive correlation between public wage gaps and unemployment, and a negative one between labour productivity and public wage gaps. Hence, a tentative conclusion is that the incentives to select into the public sector are higher in the low productivity regions, precisely those where scarcity of human capital in the private sector may be the most important factor for explaining economic backwardness.public sector, wage differentials, switching regressions, Spanish regions.

Generalized Strongly Increasing Semigroups

In this work, we present a new class of numerical semigroups called GSI-semigroups. We see the relations between them and other families of semigroups and we explicitly give their set of gaps. Moreover, an algorithm to obtain all the GSI-semigroups up to a given Frobenius number is provided and the realization of positive integers as Frobenius numbers of GSI-semigroups is studied.The first-named author was partially supported by the Spanish Projects MTM2016-80659-P and PID2019-105896GB-I00. The second and third-named authors were partially supported by the Spanish Project MTM2017-84890-P and Junta de Andalucia groups FQM-343 and FQM-366

On pseudo-Frobenius elements of submonoids of Nd

Producción CientíficaIn this paper we study those submonoids of Nd with a nontrivial pseudo-Frobenius set. In the affine case, we prove that they are the affine semigroups whose associated algebra over a field has maximal projective dimension possible. We prove that these semigroups are a natural generalization of numerical semigroups and, consequently, most of their invariants can be generalized. In the last section we introduce a new family of submonoids of Nd and using its pseudo-Frobenius elements we prove that the elements in the family are direct limits of affine semigroups.Ministerio de Economía, Industria y Competitividad (project MTM2017-84890-P)Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (project MTM2015-65764-C3-1-P

Union of Sets of Lengths of Numerical Semigroups

Let S = be a numerical semigroup, let s is an element of S and let Z(s) be its set of factorizations. The set of lengths is denoted by L(s) = {L(x(1), ... , x(p)) vertical bar (x(1), ... , x(p)) is an element of Z(s)}, where L(x(1), ... , x(p)) = x(1) + ... + x(p). The following sets can then be defined: W(n) = {s is an element of S vertical bar there exists x is an element of Z(s) such that L(x) = n}, nu(n) = boolean OR(s is an element of W(n)) L(s) = {l(1) P(N) is almost periodic with period lcm(a(1), a(p))

Análisis de la estructura del ataque en equipos de alto nivel de balonmano

Este trabajo de investigación trata de analizar a través de una metodología observacional, la estructuración del juego de ataque en balonmano de alto nivel y su eficacia en función de si se realiza transformación del sistema ofensivo o no se produce. Para llevar a cabo este trabajo se ha tomado como muestra todos los partidos que han enfrentado entre sí a los cuatro primeros equipos de la liga ASOBAL, analizando en total veinticuatro partidos. Mediante análisis estadístico, se ha valorado la significatividad de los resultados y su aplicación a una mayor población. Por último se exponen algunas consideraciones para el entrenamiento en función de los datos hallados en el estudio

An extension of Wilf's conjecture to affine semigroups

Producción CientíficaLet C ⊂ Qp be a rational cone. An affine semigroup S ⊂ C is a C-semigroup whenever (C \ S) ∩ Np has only a finite number of elements. In this work, we study the tree of C-semigroups, give a method to generate it and study their subsemigroups with minimal embedding dimension. We extend Wilf’s conjecture for numerical semigroups to C- semigroups and give some families of C-semigroups fulfilling the extended conjecture. We also check that other conjectures on numerical semigroups seem to be also satisfied by C-semigroups

Anàlisi de l’estructura de l’atac en equips d’alt nivell d’handbol

Aquest treball d’investigació tracta d’analitzar, mitjançant una metodologia observacional, l’estructuració del joc d’atac en handbol d’alt nivell i la seva eficàcia en funció del fet que es realitzi transformació del sistema ofensiu o no. Per portar a terme aquest treball s’han pres com a mostra tots els partits que han enfrontat entre ells els quatre primers equips de la lliga ASOBAL; en total, han estat analitzats vint-i-quatre partits. Mitjançant una anàlisi estadística, s’ha valorat la significança dels resultats i la seva aplicació a una població superior. Finalment, s’exposen algunes consideracions per a l’entrenament en funció de les dades trobades en l’estudi