Search results for " autore"
showing 10 items of 124 documents
La percezione dei docenti di insegnamento-apprendimento nel periodo emergenziale COVID-19: una ricerca nella Scuola Siciliana
2021
La didattica a distanza nel periodo di emergenza COVID-19 ha rappresentato una novità senza precedenti cui docenti e studenti non erano preparati. L’indagine sull'esperienza di 1364 insegnanti siciliani ha consentito di raccogliere informazioni sulle strategie organizzative e didattiche attivate, sulle criticità e sulla valutazione dell'efficacia didattica degli interventi effettuati. Sono state rilevate in modo sistematico le percezioni dei docenti relative all’autoregolazione e in particolare alla pianificazione, alle strategie di gestione delle informazioni, di correzione, e di valutazione. La ricerca nasce dal desiderio di accrescere la consapevolezza dei docenti. Conoscere gli effett…
Il Filtro Integrale Auto-Regressivo Continuo (I-ARC) per l’Analisi di Strutture Esposte al Vento
2010
In questo studio viene proposto un metodo per la rappresentazione di processi aleatori Gaussiani e stazionari, utile a modellare la turbolenza della velocità del vento, introducendo la versione integrale del modello auto-regressivo discreto già proposto in precedenza. La rappresentazione di un processo aleatorio di assegnata funzione di correlazione viene condotta integrando un’equazione integro-differenziale in cui viene coinvolto un nucleo, che rappresenta la memoria del processo, in presenza di un rumore bianco Gaussiano. La soluzione dell’equazione rappresenta un campione del processo aleatorio della turbolenza della velocità del vento. E’ stato mostrato che il modello I-ARC fornisce, n…
Džan Ailin dzīves gājums un tā atspoguļojums viņas literārajos darbos
2019
Džan Ailin ir izcila ķīniešu rakstniece, kura dzīvoja 1920.-1995. gados. Dzimusi aristokrātiskā ģimenē, rakstniece bija radīta, lai dzīvotu labu dzīvi. Bet jau agrā jaunībā meitene saprata, ka viņas dzīve nebūs viegla. Tēvs bija opija atkarīgais un māte pameta savus bērnus, lai dotos uz Franciju, jo viņas vīrs bija apņēmis mīļāko. Jaunā meitene dzīves laikā piedzīvoja dažādas nelaimes un grūtības, bet viņa iemācījās no visām šīm likstām un ķibelēm. Džan Ailin sāka padziļināti studēt ķīniešu valodu un literatūru, kā arī angļu valodu un literatūru, kas palīdzēja izveidot rakstnieces unikālo stilu, kur viņa saglabāja Ķīnas tradicionālās literatūras elementus un pievienoja tiem rietumu stilu un…
VAR modeļu un kointegrācijas analīzes pielietojums zelta cenas analīzē
2017
Darbs tiek veltīts kointegrācijai un kļūdas korekcijas modelim. Darbā dots ieskats par vienības saknes testiem, vektoru autoregresijas vienādojumiem, kointegrāciju, kļūdu korekciju modeļiem. Metodes tika pielietotas pētot sakarības starp tādiem valūtu pāriem kā zelts pret ASV dolāru (XAU/USD) un Šveices franks pret ASV dolāru (CHF/USD). Ar Engla-Greinžera un Johansena metodēm parādīts, ka periodā no 2011. gada maija līdz 2016. gada decembrim pastāv kointegrācija starp iepriekš minētajiem instrumentiem.
Impact of COVID-19 on the travel and tourism industry.
2021
Abstract Our paper is among the first to measure the potential effects of the COVID-19 pandemic on the tourism industry. Using panel structural vector auto-regression (PSVAR) (Pedroni, 2013) on data from 1995 to 2019 in 185 countries and system dynamic modeling (real-time data parameters connected to COVID-19), we estimate the impact of the pandemic crisis on the tourism industry worldwide. Past pandemic crises operated mostly through idiosyncratic shocks' channels, exposing domestic tourism sectors to large adverse shocks. Once domestic shocks perished (zero infection cases), inbound arrivals revived immediately. The COVID-19 pandemic, however, is different; and recovery of the tourism ind…
GDP clustering: A reappraisal
2012
Abstract This note explores clustering in cross country GDP per capita using recently developed model based clustering methods for panel data. Previous research characterizing the components of the overall distribution of output either use ad hoc methods, or methods which ignore/subvert the panel nature of the data. These new methods allow the characterization of the possible autoregressive relationship of output between time points. We show that traditional static clustering decade by decade gives mixed results regarding clustering over time, while the application of longitudinal mixtures presents three distinct clusters at all periods of time.
Real wages-employment relationship in Finnish manufacturing: a VAR approach
1991
Granger's concept of causality and the vector autoregressive(VAR) technique is used to investigate the real wages-employment relationship in Finnish manufacturing. The stationarity of the time series is examined and a number of co-integration tests for the adequacy of a pure VAR specification performed. The results using a bivariate VAR model based on a lag structure determined by Akaike's information criterion suggests that real wages Granger-cause employment. The slight non-constancy of the model suggests, however, that the conclusion concerning the nature of the real wages-emploment relationship should be treated with causion.
No linealidad y asimetría en el proceso generador del Índice Ibex35
2013
This paper analyzes the behavior of Ibex35 from January 1999 to December 2001, in order to check if it follows a different process from random walk so its return is not a white noise and it can be predictable, against the efficient market hypothesis. For that, a nonlinear generating process of return will be considered and a STAR-APARCH model will be specified. This model allows a nonlinear behavior in the conditional mean and in the conditional variance. The empirical results show that the Ibex35 follows a nonlinear and asymmetric process, both in the conditional mean as in the conditional variance, so the weak-version of efficient market hypothesis is rejected. El trabajo analiza el compo…
Spectral decomposition of cerebrovascular and cardiovascular interactions in patients prone to postural syncope and healthy controls.
2022
We present a framework for the linear parametric analysis of pairwise interactions in bivariate time series in the time and frequency domains, which allows the evaluation of total, causal and instantaneous interactions and connects time- and frequency-domain measures. The framework is applied to physiological time series to investigate the cerebrovascular regulation from the variability of mean cerebral blood flow velocity (CBFV) and mean arterial pressure (MAP), and the cardiovascular regulation from the variability of heart period (HP) and systolic arterial pressure (SAP). We analyze time series acquired at rest and during the early and late phase of head-up tilt in subjects developing or…
NARX Models of an Industrial Power Plant Gas Turbine
2005
This brief reports the experience with the identification of a nonlinear autoregressive with exogenous inputs (NARX) model for the PGT10B1 power plant gas turbine manufactured by General Electric-Nuovo Pignone. Two operating conditions of the turbine are considered: isolated mode and nonisolated mode. The NARX model parameters are estimated iteratively with a Gram-Schmidt procedure, exploiting both forward and stepwise regression. Many indexes have been evaluated and compared in order to perform subset selection in the functional basis set and determine the structure of the nonlinear model. Various input signals (from narrow to broadband) for identification and validation have been consider…