Search results for "33"
showing 10 items of 1917 documents
Mediterranea - ricerche storiche
2015
Rivista di Storia fondata da studiosi dell'Università di Palermo con l'intento di fornire un nuovo spazio di pubblicazione per i risultati della ricerca storica, con particolare attenzione alla Sicilia. L'arco temporale interessato copre dal Basso Medioevo all'età contemporanea
8-parameter solutions of fifth order to the Johnson equation
2019
We give different representations of the solutions of the Johnson equation with parameters. First, an expression in terms of Fredholm determinants is given; we give also a representation of the solutions written as a quotient of wronskians of order 2N. These solutions of order N depend on 2N − 1 parameters. When one of these parameters tends to zero, we obtain N order rational solutions expressed as a quotient of two polyno-mials of degree 2N (N +1) in x, t and 4N (N +1) in y depending on 2N −2 parameters. Here, we explicitly construct the expressions of the rational solutions of order 5 depending on 8 real parameters and we study the patterns of their modulus in the plane (x, y) and their …
From first to fourth order rational solutions to the Boussinesq equation
2020
Rational solutions to the Boussinesq equation are constructed as a quotient of two polynomials in x and t. For each positive integer N , the numerator is a polynomial of degree N (N + 1) − 2 in x and t, while the denominator is a polynomial of degree N (N + 1) in x and t. So we obtain a hierarchy of rational solutions depending on an integer N called the order of the solution. We construct explicit expressions of these rational solutions for N = 1 to 4.
Forensic Analysis of Fire in a Substation of a Commercial Center
2020
In this article, the authors discuss the legal liabilities of the professional engineer as both the engineer of record of a project and the construction site manager. In particular, this article analyzes the case of a fire at the end-user medium voltage–low-voltage (MV–LV) substation of a shopping center in Italy, which occurred a few years after the maintenance works on the electrical installation. The professional engineer who had designed and overseen the construction of the substation was accused of professional negligence. The authors through the examination of applicable technical standards, as well as of safety regulations, demonstrate that the professional engineer had acted diligen…
Le fratture dello scafoide carpale
2015
Sono descritte le generalità e le metodiche di diagnosi e trattamento delle fratture dello scafoide carpale
Complicanze delle fatture dello scafoide carpale
2016
Le fratture dello scafoide carpale sono relativamente rare e avvengono soprattutto nei giovani in seguito a traumi ad alta energia. Per via della sua particolare conformazione anatomica e per la sua vascolarizzazione, è importante un’attenta valutazione del tipo di frattura per individuare il più corret- to approccio terapeutico, al ne di prevenire le non rare complicanze quali: ritardo di consolidazione, viziosa consolidazione e pseudoartrosi. Diverse sono le classi cazioni delle fratture e delle pseudoartrosi proposte da vari autori, le quali convergono sull’importanza della valutazione della stabilità dei frammenti. Le fratture di scafoide stabili bene ciano in genere di un trattamento i…
Testing the Modified Sediment Delivery Model (MOSEDD) at SPA2 Experimental Basin, Sicily (Italy)
2017
A new version of a spatially distributed sediment delivery model taking into account the hillslope sediment transport efficiency, named MOSEDD, is presented. This model gives estimates of basin sediment yield at event scale, which are more reliable than those obtained by the original SEDD. For SPA2 basin discretized into morphological units, four different calculation schemes of MOSEDD, including the original SEDD version, were applied. All parameterization schemes of the model were calibrated using 15 events measured at the outlet of the experimental basin in the period February 2005–February 2010. The model calibration was used to determine a relationship between the coefficient βe of the…
Stress, angst og selvtillit i toppfotball : Hvilken betydning har mental tøffhet for angst og selvtillit i forkant av kampsituasjon blant fotballspil…
2017
Masteroppgave idrettsvitenskap ME517 - Universitetet i Agder 2017 Stress, anxiety and self-esteem are key concepts in sports psychology and performance. How these factors affect athletes in terms of achievement is an interesting area and the main background for this study. The purpose of this study was to investigate the meaning of mental toughness (MT) compared to cognitive anxiety, somatic anxiety and self-esteem ahead of soccer matches among high-level soccer players. The selection in this study was the first-team squad of Arendal fotball, consisting of 23 players from 18 to 37 years of age. During the project, Arendal fotball took part in the PostNord-league section four, which represen…
Performance Improvement of Grid-Integrated Doubly Fed Induction Generator under Asymmetrical and Symmetrical Faults
2023
The doubly fed induction generator (DFIG)-based wind energy conversion system (WECS) suffers from voltage and frequency fluctuations due to the stochastic nature of wind speed as well as nonlinear loads. Moreover, the high penetration of wind energy into the power grid is a challenge for its smooth operation. Hence, symmetrical faults are most intense, inflicting the stator winding to low voltage, disturbing the low-voltage ride-through (LVRT) functionality of a DFIG. The vector control strategy with proportional–integral (PI) controllers was used to control rotor-side converter (RSC) and grid-side converter (GSC) parameters. During a symmetrical fault, however, a series grid-side converter…
A Model for the Study of Sheath Currents in Medium Voltage Cables for Industrial Application
2020
In this paper, the implementation of a simulation model for studying the effect of cross-bonding of metallic sheaths and/or non-magnetic armor of single-core medium voltage cables in the same circuit is discussed. With the use of single-core cables, the resistive losses due to the induced circulating currents in cable sheaths or armors causes an increase of cable temperature that reduces its ampacity. In addition, the risk of electric shock due to induced voltages may be present if a person is exposed to the armor/sheath at the unbounded end. For this reason, special bonding techniques are used to significantly reduce these currents. The authors have implemented a model that could be used t…