Search results for "methodology."
showing 10 items of 822 documents
Efficient extraction and preparative separation of four main isoflavonoids from Dalbergia odorifera T. Chen leaves by deep eutectic solvents-based ne…
2016
In this study, green and efficient deep eutectic solvent-based negative pressure cavitation-assisted extraction (DES-NPCE) followed by macroporous resin column chromatography was developed to extract and separate four main isoflavonoids, i.e. prunetin, tectorigenin, genistein and biochanin A from Dalbergia odorifera T. Chen leaves. The extraction procedure was optimized systematically by single-factor experiments and a Box-Behnken experimental design combined with response surface methodology. The maximum extraction yields of prunetin, tectorigenin, genistein and biochanin A reached 1.204, 1.057, 0.911 and 2.448mg/g dry weight, respectively. Moreover, the direct enrichment and separation of…
Interventistica eco-guidata per l’articolazione d’anca
2013
Lo scopo di questo lavoro è di rivedere le principali applicazioni della interventistica eco-guidata d’anca, descrivendone le indicazioni e la metodologia. L’ecografia è una metodica considerata sicura per i pazienti, in quanto non è stato dimostrato un possibile danno dovuto all’energia trasmessa dagli ultrasuoni ai tessuti del paziente, contrariamente alle metodiche che fanno uso di radiazioni ionizzanti, come la radiografia convenzionale e la tomografia computerizzata. Inoltre, l’ecografia risulta rapida ed efficace nel guidare l’ago verso la sede voluta evitando di intercettare strutture vascolari e/o nervose, consentendo quindi una maggiore sicurezza, rispetto alle tecniche interventis…
E-portfolio e flipped classroom: un’indagine esplorativa con i futuri insegnanti di scuola primaria
2023
Il contributo intende far riflettere sul tema della formazione dei futuri insegnanti di scuola primaria, a partire dall’impiego dell’e-portfolio come dispositivo innovativo per promuovere l’acquisizione della competenza riflessiva e autovalutativa all’interno della flipped classroom. La ricerca, che ha coinvolto 154 studenti del Corso di laurea magistrale in Scienze della Formazione Primaria dell’Università degli Studi di Palermo, che frequentavano il corso di Docimologia nell’anno accademico 2020/2021, presenta i presupposti teorici, gli obiettivi e le modalità operative di un percorso che ha visto l’impiego dell’e-portfolio nella flipped per promuovere lo sviluppo delle competenze docimol…
On the self-heating behavior of upgraded biochar pellets blended with pyrolysis oil: Effects of process parameters
2020
Abstract Biochar obtained from biomass pyrolysis is a promising carbon neutral material which can be used in substitution of fossil coal and coke in metallurgical applications. Biochar’s mechanical properties improve significantly without compromising reactivity, when upgraded by densification with pyrolysis oil and reheated. However, upgraded biochar pellets use in the industry is limited due to the risks associated with self-heating. This issue must be seriously considered for further industrial production of upgraded biochar pellets. Self-heating oven tests are generally time-consuming and limit the possibility of testing various potential solutions. The aim of this work was both to inve…
中国现当代诗歌的西方视野
2018
Il volume, composto da saggi critici, presenta alcuni degli aspetti che caratterizzano il panorama della produzione poetica cinese contemporanea. Si muove sulla linea di una proposta metodologica di lettura e interpretazione critica della poesia cinese.
Advances in Spatial Econometrics: Methodology, Tools and Applications
2005
Luc Anselin, Raymond Florax, Sergio Rey, Springer, 2004; Recension publié dans : Journal of Regional Science, 45, 4, p. 866-870
Limitations of Cross-Cultural Customer Satisfaction Research and Recommending Alternative Methods
2004
SUMMARY Cross-cultural research in tourism is receiving increasing attention from academics. Little, however, has been done with regard to the assessment of cultural differences in tourist satisfaction. Research in tourism marketing has recognized the need for further research in cross-cultural satisfaction research, and specifically, in equivalence issues regarding the measurement of tourist satisfaction. Consequently, the aim of this conceptual paper is to focus attention on the importance of exploring cross-cultural differences in customer satisfaction research. The principal contributions are three-fold: (1) to emphasize the significance of exploring cross-cultural differences while att…
MAXQDA and its application to Social Sciences: a comparative case study on urban vulnerability
2022
Introducción. En el ámbito de las Ciencias Sociales cada vez es más frecuente el empleo de programas informáticos en el análisis de datos cuantitativos y cualitativos. El presente artículo tiene por objeto presentar la aplicación del software MAXQDA a partir de un estudio de caso comparado sobre vulnerabilidad urbana en el Sur (Guatemala) y en el Norte (España). Para ello, se presenta una revisión teórica internacional sobre la aplicación de plataformas ofimáticas bajo la denominación de CAQDAS, cuyo surgimiento y aplicación ha supuesto en el ámbito de la investigación social nuevos métodos de análisis cualitativos y mixtos. Dentro de dicha denominación, MAXQDA se presenta como una platafor…
The Role of Covariance Matrix Forecasting Method in the Performance of Minimum-Variance Portfolios
2014
Providing a more accurate covariance matrix forecast can substantially improve the performance of optimized portfolios. Using out-of-sample tests, in this paper, we evaluate alternative covariance matrix forecasting methods by looking at (1) their forecast accuracy, (2) their ability to track the volatility of the minimum-variance portfolio, and (3) their ability to keep the volatility of the minimum-variance portfolio at a target level. We find large differences between the methods. Our results suggest that shrinkage of the sample covariance matrix improves neither the forecast accuracy nor the performance of minimum-variance portfolios. In contrast, switching from the sample covariance ma…
An Introduction: "to train and to be trained"
2020
The chapter describes the training model of "Experts in proximity violence and its two main features: 1. the identification of training goals capable of providing specific tools, methods and skills; 2. the creation of a training-course prototype capable of integrating the proposed objectives and the relevant contents in terms of professional spendability.