Search results for " Multilevel."
showing 10 items of 64 documents
A spatial multilevel analysis of Italian SMEs Productivity
2009
In this paper, we adapt multilevel analysis methods to investigate the spatial variability of SMEs productivity across the Italian territory, and account for differences in the socio-economic context. Our results suggest that to properly capture the variability of the data, it is important to allow for both spatial mean and slope effects. Social decay has the expected negative impact. However, while this effect is larger on firms with smaller capital intensity, firms with higher capital intensity seem to be less affected by geography. Greater territorial heterogeneity emerges among those firms with lower capital to labour ratios.
A Spatial Multilevel Analysis of Italian SMEs Productivity
2009
Abstract In this paper, we adapt multilevel analysis methods to investigate the spatial variability of SMEs' productivity across the Italian territory, and account for differences in the socio-economic context. Our results suggest that to properly capture the variability of the data, it is important to allow for both spatial mean and slope effects. Social decay has the expected negative impact. However, while this effect is larger on firms with smaller capital intensity, firms with higher capital intensity seem to be less affected by geography. Greater territorial heterogeneity emerges among those firms with lower capital to labour ratios. Une analyse spatiale a plusieurs niveaux de la prod…
Dead-time impact on the harmonic distortion and conversion efficiency in a three-phase five-level Cascaded H-Bridge inverter: mathematical formulatio…
2023
To avoid leg short-circuit in inverters, dead time must be introduced on leg gate signals. Dead time affects the inverter output voltage fundamental harmonic amplitude, voltage harmonic distortion and inverter efficiency by introducing additional voltage drops. In this regard, dead time effects have been widely investigated for traditional two-level three-phase voltage source inverters in the literature but not extensively for multilevel topology structures. This paper provides a detailed analysis of dead time impact on the harmonic distortion and efficiency of Cascaded H-Bridges Multilevel Inverters (CHBMIs). For this purpose, a general mathematical formulation to determine voltage drop du…
España inacabada. Organización territorial del Estado, autonomía política y reconocimiento de la diversidad nacional
2021
S’han complert més de tres dècades de vigència de la Constitució de 1978 i, per tant, ja es disposa de prou perspectiva per analitzar el grau d’eficàcia d’un model d’Estat, per alguns, gairebé federal i, per a uns altres, senzillament molt descentralitzat. D’altra banda, a Espanya segueix plenament obert el debat sobre Espanya. Sigui quina sigui l’opinió, la veritat és que el nostre antic problema consumeix una gran part de les energies col·lectives, condiciona àmpliament l’agenda política, genera notables tensions socials i projecta ombres d’incertesa respecte al futur. En aquest treball, s’hi presenta un balanç de les dues qüestions. Després d’oferir un resum breu del procés de construcci…
Graphical THD minimization procedure for single phase five-level converters
2017
This paper proposes two graphycal procedure to mitigate h harmonics and to minimize the total harmonic distortion (THD), respectively. The paper considers a five-level inverter and fundamental frequency modulation: it computes the two switching angles able to reduce low order harmonics and able to minimize the THD. Simulation results are obtained and, in order to validate the proposed procedure, an experimental prototype is built and experimental results are carried out. The comparison between simulation and experimental results confirms the accuracy of the proposed graphycal procedure. It is shown that the switching angles to mitigate the third-fifth and the third-fifth-seventh harmonics e…
Immigrati e diritti sociali: parità di trattamento e tutela multilivello
2017
Il saggio analizza la tutela antidiscriminatoria di cui godono i lavoratori immigrati all'insegna di una prospettiva multilivello: più in particolare viene descritto il complesso di strumenti normativi del diritto nazionale ed europeo a tutela delle situazioni giuridiche soggettive degli immigrati (ad es., in materia di sicurezza sociale), per come interpretato dalla Corte Costituzionale, dalla Corte di Giustizia e dalla Corte EDU. Da ultimo, vengono analizzati i recenti orientamenti giurisprudenziali, che oscillano tra l'affievolimento del principio paritario in ragione di sempre più stringenti vincoli di bilancio, e la tendenziale parificazione tra cives e non cives alla luce del principi…
Italian Deprivation Index and Dental Caries in 12-Year-Old Children: A Multilevel Bayesian Analysis
2014
Evidence from the literature has shown that people with a lower socioeconomic status enjoy less good health than people with a higher socioeconomic status. The Italian deprivation index (DI) was used with the aim to evaluate the association between the DMFT index and risk factors for dental caries, including city population and DI. The study included 4,305 12-year-old children living in 38 cities classified by demographic size as small, midsize and large. Zero-inflated negative binomial multilevel regression models were used to assess risk factors for DMFT and to address excess of zero DMFT and overdispersion through a Bayesian approach. The difference in the average level of DMFT among chi…
Does single-event multilevel surgery enhance physical functioning in the real-life environment in children and adolescents with cerebral palsy (CP)?:…
2013
Orthopedic procedures are a method of treating gait deviations and musculoskeletal pathology that develop with age in cerebral palsy (CP). Recently single-event multilevel surgery (SEMLS) has become common practice. Although there is evidence that SEMLS could improve gait, it is unclear whether it will enhance overall physical functioning and coping strategies in the real-life environment. It is unclear how improved walking capacity affects actual functioning and enables greater independence. The aim of this study was to examine the perceptions of adolescents concerning the results of surgery on personal physical functioning in the environment five or more years after SEMLS. In this study, …
La sopravvivenza immediata delle start-up italiane del settore manifatturiero sanitario: un'analisi multilevel
2017
The immediate survival of the Italian start-up businesses in healthcare industry: a multilevel analysis Objectives: The purpose of this contribution is to provide novel evidence about the main determinants of the short-run survival of pharmaceutical and medical device manufacturing start-up firms in Italy. In order to assess both the firm-specific determinants and the observed and unobserved regional and contextual characteristics, we model the three-year firm survival probability by means of a multilevel logistic framework. Methods and Results: The empirical analysis focuses on an internationally comparable database of the population of firms built up and managed by the Italian National In…
Estimating Verdoorn law for Italian firms and regions
2011
In empirical regional economics, returns to scale are typically estimated at the regional level in search for evidence on alternative theories of growth and agglomeration. However, returns to scale may also have a firm-level dimension. In this paper, we exploit micro level data and estimate the dynamic Verdoorn law in a multilevel-setting, where returns to scale are obtained simultaneously for the micro and the regional level. Using Italian firm-level data and the NUTS-3 level of aggregation, we estimate the classic and augmented versions of Verdoorn law for the manufacturing sector, and the rest of the economy for comparison. Our results show that increasing returns to scale co-exist at bo…