Search results for " CLUSTER"

Correlation based hierarchical clustering in financial time series

2005

We review a correlation based clustering procedure applied to a portfolio of assets synchronously traded in a financial market. The portfolio considered consists of the set of 500 highly capitalized stocks traded at the New York Stock Exchange during the time period 1987-1998. We show that meaningful economic information can be extracted from correlation matrices.

Coupled-cluster methods including noniterative corrections for quadruple excitations

2005

A new method is presented for treating the effects of quadruple excitations in coupled-cluster theory. In the approach, quadruple excitation contributions are computed from a formula based on a non-Hermitian perturbation theory analogous to that used previously to justify the usual noniterative triples correction used in the coupled cluster singles and doubles method with a perturbative treatment of the triple excitations (CCSD(T)). The method discussed in this paper plays a parallel role in improving energies obtained with the full coupled-cluster singles, doubles, and triples method (CCSDT) by adding a perturbative treatment of the quadruple excitations (CCSDT(Q)). The method is tested fo…

The role of Palermo’s wine shops in the business of quality wine

2009

In the last few years, due to changes of consumers’ eating habits “quality wine” (“DOCG” – Designation of Origin Guaranteed, “DOC” – Designation of Origin, “IGT” – Typical Geographic Indication) demand has significantly changed. Wine, no longer considered only as an alcoholic drink, it now represents something that needs to satisfy the consumer’s desire of wellness and wellbeing. The evolution of wine sector, primarily related to consumer’s changes in eating habits and lifestyles, has also impacted some area of the supply chain as product distribution and sales. This growing business, characterized by having different types of distribution channels that cover demand of wine at different con…

Wine and quality. A cluster anlysis to assess certain representative aspects relating to the quality

2009

This research, in which the technique of Cluster Analysis is used, will provide information on how wine producers can evaluate certain characteristics (variables) of their product more widely associated as indicative of quality. The analysis identified homogeneous groups containing within them other, related variables, which can be considered similar. Those attributes which are by themselves most representative of the product's quality are also highlighted. Finally, the cluster analysis made it possible to comment on the behaviour of producers, and looking at how they seek to meet market expectations based on their knowledge of customer's habits in the buying and consuming of wine.

Food sustainability perception at universities: Education and demographic features effects

2022

The 2030 Agenda of the United Nations merged in 17 goals the strong need to change the pattern of human life on the planet in a path of strengthening sustainability especially in an era that is widely defined as Anthropocene. The Global Action Program (GAP) on Education and Sustainable Development was adopted based on the power of education and knowledge with the idea of 'green universities' aimed at improving the perception of sustainability for future policy decisions. Based on a Best-Worst (BW) scaling methodological approach, in this study we quantified the preferences of generation Y at University of Turin as they relate to issues explicitly connected to the ordinary consumption of foo…

Genetic characterization of the Mascaruna goat, a Sicilian autochthonous population, using molecular markers

2013

The aim of this work was to characterize a Sicilian autochthonous goat population using microsatellite markers and genetic polymorphisms at the casein genes. In order to investigate the genetic structure of the Mascaruna goat, a total of 60 (20 Girgentana, 20 mixed populations, and 20 Mascaruna) individuals were analyzed, using a panel of 18 microsatellite markers. Moreover, the Mascaruna goats were genotyped at casein loci using several molecular techniques. Based on the genetic structure at casein genes, the Mascaruna goat was similar to most goat breeds from the Mediterranean area, which are characterized by the predominance of strong alleles. The low value of genetic differentiation amo…

Studio teorico della reazione di idroisomerizzazione del cis-butene su cluster di palladio supportato

2008

BIOSYNTHESIS OF HEROCYCLES. FROM ISOLATION TO GENE CLUSTER

2015

This book describes biosynthetic methods to synthesize heterocyclic compounds, offering a guide for the development of new drugs based on natural products. The authors explain the role of natural products in chemistry and their formation along with important analytical methods and techniques for working with heterocycles. • Covers methods and techniques: isotopic labelling, enzymes and mutants, and pathway identification • Provides a thorough resource of information specifically on heterocyclic natural products and their practical biosynthetic relevance • Explains the role of natural products in chemistry and their formation • Discusses gene cluster identification and the use of biogenetic …

An Inquiry-Based Approach to a Pedagogical Laboratory for Primary School Teacher Education

2017

In questo articolo vengono presentati e di- scussi alcuni risultati relativi alla sperimen- tazione di due esperienze di didattica laboratoriale della fisica, una basata su me- todi di indagine scientifica e l’altra su meto- dologie didattiche più “tradizionali”, svolte durante l’A.A. 2014-15 con studenti del CdL in Scienze della Formazione Primaria del- l’Università di Palermo. I dati, analizzati tra- mite metodi quantitativi, sono stati ricavati dalla somministrazione prima, durante e do- po le attività laboratoriali, di un questionario finalizzato a comprendere gli stili di insegna- mento preferiti dagli studenti, la motivazio- ne di questi all’apprendimento/insegna- mento delle scienze …

Multidimensional Scaling in Cluster Analysis: examples in Science and Mathematics Education

2021

Several researches in STEM education research highlight the advantages of an inte- grated approach to these disciplines that relates knowledge and know-how, design and implementation, theoretical and practical problems [5, 4, 6]. In some researches, the effectiveness of these approaches on students conceptual understanding and motivation and has been studied through the use of quantitative analysis tools such as cluster analysis (CLA) [1, 7]. Through CLA it is possible to characterize students analyzing the strategies they deploy to tackle, for example, questionnaires built so as to investigate the lines of reasoning implemented by them when they are proposed with problematic situations. In…