2,521 research outputs found
Immigrants’ settlement patterns in the city of Naples
ABSTRACT. Residential segregation is the outcome of both economic inhomogeneities within the urban space and attraction among individuals sharing the same ethnicity. Here we focus on the settlement patterns originated by different groups of immigrants in the city of Naples. We use the inhomogeneous L-function for measuring segregation due to spatial attraction, while adjusting for the effects of inhomogeneity. Monte Carlo simulations have been used to build confidence envelopes for the null hypothesis of absence of spatial attraction. All nationalities exhibited significant spatial attraction at all considered distances, except for Romania and Poland. However, spatial attraction resulted much stronger for immigrants from Pakistan, China, and Sri Lanka.
RIASSUNTO. La segregazione residenziale è la risultante di disomogeneità economiche all’interno dello spazio urbano e dell’attrazione tra individui della stessa etnia. In questo lavoro, noi considerazione i modelli insediativi originati da diversi gruppi di immigrati stranieri nella città di Napoli ed impieghiamo la funzione L disomogenea per misurare la segregazione causata dall’attrazione spaziale, tenendo sotto controllo le disomogeneità spaziali. Tramite simulazioni Monte Carlo abbiamo costruito degli intervalli di confidenza per l’ipotesi nulla di assenza di attrazione. Tutte le nazionalità analizzate hanno mostrato un’attrazione spaziale significativa a tutte le distanze considerate, ad eccezione di Rumeni e Polacchi. Un’attrazione più forte è stata osservata per gli immigrati provenienti dal Pakistan, Cina e Sri Lanka
Could the Bass model be applied to Italian emigration?
Objectives. Our work is a first attempt at verifying whether the diffusionist theory - a framework extensively employed in the demographic literature to interpret the spread of new ideas and practices - can adequately and meaningfully explain migration decisions and related migration data.
Methods. We test whether the Bass model can properly fit the new Italian emigration when working with absolute values. In this sense, we propose interpolation applications for the different Italian macro-areas, separately.
Results. The Bass model detects geographic differences in the underlying dynamics governing the new emigration flows. In Bass terms, the diffusion of the new emigratory behaviour travels at two different speeds in the Northern-Central Italy and in the South. The forces governing the pace of diffusion also reveal a geographic heterogeneity, presenting North-South divergences
Rapid determination of moment magnitude from the near-field spectra: application to the april 6 2009, L'Aquila seismic sequence
On April 6th 2009, a magnitude Mw=6.1 earthquake struck the Abruzzi region in central Italy. Despite its moderate size, the earth- quake caused more than 300 fatalities and partially destroyed the city of L’Aquila and many villages in its surroundings. The main shock was preceded by an earthquake swarm that started at the end of 2008, and, by the end of November 2009, more than 16,000 aftershocks with M> 0.5 have been recorded by the INGV seismic network.
Current advances in data transmission and communication yield high quality broadband velocity and strong motion waveforms in near real-time. These data allow for the rapid characterization of earthquake sources in terms of fault geometry, focal depth and seismic moment. Delouis et al. (2009) have developed a methodology for rapid determination of moment magnitude from the near-fields spectra. In this study we test this methodology on the L’Aquila sequence earthquakes for which we have already com- puted the time domain moment tensor solutions (TDMT, Scognamiglio et al., 2010)
An Extended Approach to the Evaluation of Energy Storage Systems: A Case Study of Li-Ion Batteries
Energy storage technologies can act as flexibility sources for supporting the energy tran-
sition, enabling the decarbonisation of the grid service provision and the active engagement of the
customers (both prosumers and consumers), opening for them new business opportunities. Within
storage technologies, Lithium-ion (Li-ion) batteries represent an interesting solution for dealing with
the majority of these services. In this context, this study addresses an evaluation of economic, environ-
mental and geopolitical risks with reference to the critical raw materials used in the manufacturing of
Lithium Iron Phosphate (LFP) Li-ion batteries. The assessment entailes grid and prosumer services
that these batteries can provide. The exploited economic indicator is the Levelised Cost of Storage,
whereas six environmental indicators are used for environmental impact estimation. Cycle stages
accounted for in the analysis are the manufacturing and use phases. Finally, the evaluation of the
impact of critical raw materials is performed by deploying a Supply Risk indicator, which is instead
assessed considering every single material and the overall risk for the battery. High-risk materials are
represented by Graphite and Phosphorous. Results denote that, for each service, the number of cycles
and the discharge duration are pivotal to make the investment economically and environmentally
sustainable. The reduction in the Net Import Reliance, as well as the increase in the Recycling Rate,
could sensibly reduce the risk associated with battery raw material
Development of a multifunctional panel for aerospace use through SLM additive manufacturing
Lattice materials can overcome the need of light and stiff structures in the aerospace industry. The wing leading edge is one of the most critical
parts for both on-board subsystem and structure features: it must withstand to the aerodynamic loads and bird-strike, integrating also the anti-ice
system functions. Nowadays, this part is made by different components bonded together such as external skin, internal passageways, and feeding
tubes. In the present work, a single-piece multifunctional panel made by additive manufacturing will be developed. Optimal design and
manufacturing are discussed according to technological constraints, aeronautical performances and sustainability
TAKING CARE OF INTELLECTUAL DISABILITIES IN THE ERA OF COVID-19: BIOLOGICAL SUBSTRATES, PERSONALIZED MEDICINE AND COUNSELING
TAKING CARE OF INTELLECTUAL DISABILITIES IN THE ERA OF COVID-19: BIOLOGICAL SUBSTRATES, PERSONALIZED MEDICINE AND COUNSELING
The short-term supplementation of monacolin K improves the lipid and metabolic patterns of hypertensive and hypercholesterolemic subjects at low cardiovascular risk
A nutraceutical compound containing 10 mg of MK appeared to be safe, well tolerated and effective at improving lipid and glucose patterns
flexCWM: A Flexible Framework for Cluster-Weighted Models
Cluster-weighted models (CWMs) are mixtures of regression models with random covariates. However, besides having recently become rather popular in statistics and data mining, there is still a lack of support for CWMs within the most popular statistical suites. In this paper, we introduce flexCWM, an R package specifically conceived for fitting CWMs. The package supports modeling the conditioned response variable by means of the most common distributions of the exponential family and by the t distribution. Covariates are allowed to be of mixed-type and parsimonious modeling of multivariate normal covariates, based on the eigenvalue decomposition of the component covariance matrices, is supported. Furthermore, either the response or the covariates distributions can be omitted, yielding to mixtures of distributions and mixtures of regression models with fixed covariates, respectively. The expectation-maximization (EM) algorithm is used to obtain maximum-likelihood estimates of the parameters and likelihood-based information criteria are adopted to select the number of groups and/or a parsimonious model. For the component regression coefficients, standard errors and significance tests are also provided. Parallel computation can be used on multicore PCs and computer clusters, when several models have to be fitted. To exemplify the use of the package, applications to artificial and real datasets, included in the package, are presented
A novel model reference adaptive control approach investigation for power electronic converter applications
This paper demonstrates the viability and effectiveness of a novel adaptive control approach applied to power electronic converters. A methodology based on the formulation of a Lyapunov-based approach is showcased to represent the operation of a new adaptive controller for the regulation of two power converter topologies (Buck and Boost). The models of the Buck and Boost converter topologies include the parasitic parameters that represent the non-ideal components. The basic idea of the control approach is to demonstrate adaptive stabilization for the proposed non-linear system. The most important design specification to stabilize the system is to track the reference trajectory in such a way that the error on the output variable converges asymptotically to zero. This adaptation mechanism is explicitly designed so that the asymptotic stability of the equilibrium condition is guaranteed according to the Lyapunov theorem and sensitivity theory. The details of the design algorithm are explained in the paper. The proposed control approach has been compared to other Lyapunov-based control techniques proposed in literature for the same non-ideal converters. The results show that the proposed controller provides better level of robustness and performance than the other wellestablished Lyapunov based controllers. To verify the effectiveness of the controller in real time, a test bench has been set up with prototypes of both converters and the controller has been implemented using the Arduino microcontroller and the control system driven through the Matlab/Simulink platform
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