Search results for " Opera"
showing 10 items of 3606 documents
Social capital in the international operations of family SMEs
2012
PurposeThe aim of this study is to discuss how social capital is developed in the internationalization process of small and medium‐sized family enterprises (family SMEs).Design/methodology/approachThis paper reports findings from an in‐depth multiple case study with four Finnish manufacturing family SMEs. The data were analyzed through the perspectives of structural holes, network closure, and the interplay between these two mechanisms.FindingsThe material in the paper demonstrated that family entrepreneurs had a large number of structural holes when launching international operations, but also after several years of running international operations. Instead of trying to span structural hol…
Inverse problems for a fractional conductivity equation
2020
This paper shows global uniqueness in two inverse problems for a fractional conductivity equation: an unknown conductivity in a bounded domain is uniquely determined by measurements of solutions taken in arbitrary open, possibly disjoint subsets of the exterior. Both the cases of infinitely many measurements and a single measurement are addressed. The results are based on a reduction from the fractional conductivity equation to the fractional Schr\"odinger equation, and as such represent extensions of previous works. Moreover, a simple application is shown in which the fractional conductivity equation is put into relation with a long jump random walk with weights.
ANALISI GIS E MODELLI STATISTICI PER LA VALUTAZIONE DELLA SUSCETTIBILITÀ DA FRANA A SCALA DI BACINO: IL CASO STUDIO DEL BACINO DEL TORRENTE MARVELLO
Lo studio condotto nel presente lavoro di tesi ha affrontato il tema della valutazione, a scala di bacino idrografico, della suscettibilità ai fenomeni di tipo colamento, attraverso l’applicazione di modelli statistici e tecniche di analisi spaziale GIS. La fase iniziale della preparazione di un modello di suscettibilità da frana prevede la realizzazione di un inventario degli eventi verificatesi nell’area di studio. Questo passo è di fondamentale importanza, considerando che proprio attraverso l’archivio frane è possibile analizzare ed individuare le condizioni che in passato hanno favorito l’innesco dei movimenti di versante. L’identificazione di queste condizioni, infatti, consente di pr…
Characterizing and Quantifying Frustration in Quantum Many-Body Systems
2011
We present a general scheme for the study of frustration in quantum systems. We introduce a universal measure of frustration for arbitrary quantum systems and we relate it to a class of entanglement monotones via an exact inequality. If all the (pure) ground states of a given Hamiltonian saturate the inequality, then the system is said to be inequality saturating. We introduce sufficient conditions for a quantum spin system to be inequality saturating and confirm them with extensive numerical tests. These conditions provide a generalization to the quantum domain of the Toulouse criteria for classical frustration-free systems. The models satisfying these conditions can be reasonably identifi…
Spherical harmonic expansion of fundamental solutions and their derivatives for homogenous elliptic operators
2017
In this work, a unified scheme for computing the fundamental solutions of a three-dimensional homogeneous elliptic partial differential operator is presented. The scheme is based on the Rayleigh expansion and on the Fourier representation of a homogeneous function. The scheme has the advantage of expressing the fundamental solutions and their derivatives up to the desired order without any term-by-term differentiation. Moreover, the coefficients of the series need to be computed only once, thus making the presented scheme attractive for numerical implementation. The scheme is employed to compute the fundamental solution of isotropic elasticity showing that the spherical harmonics expansions…
La caída de las cajas de ahorros españolas. Cuestión de rentabilidad, tamaño y estructura de propiedad=The Fall of Spanish Savings Banks. Question of…
2012
En España entre 2010 y 2011 se ha producido una gran restructuración financiera, que ha llevado a la práctica desa-parición de las Cajas de Ahorros mediante fusiones y posterior cambio de estructura de la propiedad convirtiéndose en bancos. Esta gran restructuración ha sido promovida por el Banco de España, como salida para que las entidades financieras subsistieran a la crisis que les afectaba. Este trabajo analiza los bancos y cajas del sistema financiero español durante los cuatro años previos al comienzo de la reestructuración financiera del 2010. El objetivo es comprobar si existen diferencias en cuanto a rentabilidad por causas de tamaño y tipo de gobierno de la entidad (cajas de ahor…
deaR-Shiny: An Interactive Web App for Data Envelopment Analysis
2021
In this paper, we describe an interactive web application (deaR-shiny) to measure efficiency and productivity using data envelopment analysis (DEA). deaR-shiny aims to fill the gap that currently exists in the availability of online DEA software offering practitioners and researchers free access to a very wide variety of DEA models (both conventional and fuzzy models). We illustrate how to use the web app by replicating the main results obtained by Carlucci, Cirà and Coccorese in 2018, who investigate the efficiency and economic sustainability of Italian regional airport by using two conventional DEA models, and the results given by Kao and Liu in their papers published in 2000 and 2003, wh…
Punishment and efficiency: theoretical and experimental approaches
2018
Los dilemas sociales se caracterizan por la desalineación de incentivos privados y sociales bajo preferencias egoístas. Mientras el óptimo social se alcanza mediante la implementación de un conjunto particular de acciones, los incentivos individuales mueven a los agentes a comportarse de una manera diferente, lo cual lleva a resultados ineficientes. Un ejemplo clásico es la provisión de un bien público, donde el óptimo se alcanza si todos contribuyen, sin embargo hay una desviación unilateral provechosa a hacer de polizón, es decir, a no contribuir al bien público y beneficiarse de los demás. De este modo, dar a los agentes egoístas la posibilidad de elegir libremente sus asignaciones lleva…
A non-cooperative approach to the folk rule in minimum cost spanning tree problems
2023
This paper deals with the problem of finding a way to distribute the cost of a minimum cost spanning tree problem between the players. A rule that assigns a payoff to each player provides this distribution. An optimistic point of view is considered to devise a cooperative game. Following this optimistic approach, a sequential game provides this construction to define the action sets of the players. The main result states the existence of a unique cost allocation in subgame perfect equilibria. This cost allocation matches the one suggested by the folk rule. The authors thank the support of the Spanish Ministry of Science, Innovation and Universities, the Spanish Ministry of Economy and Compe…
Density flow over networks: A mean-field game theoretic approach
2014
A distributed routing control algorithm for dynamic networks has recently been presented in the literature. The networks were modeled using time evolution of density at network edges and the routing control algorithm allowed edge density to converge to a Wardrop equilibrium, which was characterized by an equal traffic density on all used paths. We borrow the idea and rearrange the density model to recast the problem within the framework of mean-field games. The contribution of this paper is three-fold. First, we provide a mean-field game formulation of the problem at hand. Second, we illustrate an extended state space solution approach. Third, we study the stochastic case where the density …