Search results for "Content"
showing 10 items of 1859 documents
Luminescence of oxygen related defects in zirconia nanocrystals
2007
The luminescence of undoped tetragonal structure ZrO2 nanocrystals was studied. The luminescence intensity depends on oxygen content in gases mixture in which the nanocrystals were annealed. The distorted Zr-O bond is suggested to be the recombination center for band carriers. The oxygen deficient defect is proposed to be responsible for photoluminescence. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Il ruolo del white paper sulle offerte al pubblico di cripto-attività alla luce della proposta MiCA
2022
La proposta MiCA, nel regolare il white paper sulle offerte di crypto-assets, sembra tenere in considerazione i benefici e i limiti dei sistemi di voluntary e di mandatory disclosure, non optando integralmente né per il primo, né per il secondo. In quest’ottica, se può condividersi l’approccio regolamentare diretto a graduare, a seconda della tipologia di token offerto, sia il contenuto che l’assoggettamento del documento a mera notifica o ad approvazione ex ante da parte dell’Autorità competente, dubbi sorgono in ordine all’indistinta allocazione dell’onere della prova in capo all’oblato, nei casi di violazione della disciplina del relativo white paper.
L'intonaco Li Vigni nell'architettura del XX secolo a Palermo. Nuove conoscenze e applicazioni diagnostiche per la manutenzione
2013
Il saggio presenta lo studio degli intonaci formulati per imitare le pietre e i marmi naturali che si diffondono in Sicilia all’inizio del XX secolo ed evidenzia che le prime applicazioni e la diffusione delle nuove malte, anche nel resto dell’Italia, risentono delle sperimentazioni condotte in tutta l’Europa. Il contributo riassume i risultati di una rigorosa e capillare ricognizione tra i brevetti conservati presso l’Archivio Centrale dello Stato a Roma inerenti alle malte per il confezionamento dell’intonaco a “finta pietra”, ne analizza i contenuti in modo critico e pone in risalto i contatti culturali con le sperimentazioni dei materiali in atto nell’ambito dei grandi cantieri di resta…
Design e narrazioni
2022
Il testo nasce dall’esigenza di mettere a fuoco le implicazioni cognitive, metodologiche e progettuali del concetto di narrazione, sempre più ricorrente nella nostra esperienza quotidiana soprattutto per le molteplici forme di comunicazione e di produzioni culturali che vi si ispirano; si tratta di un concetto che anche nella riflessione teorica e nella progettualità del design sta alimentando dimensioni fortemente innovative ed evolutive nella costruzione, comunicazione di significati, contenuti immateriali, esperienze e valori emozionali che si sovrappongono e s’intrecciano all’espressione tangibile e funzionale degli oggetti, degli artefatti comunicativi, degli spazi. Si propone un perco…
A Logical Key Hierarchy Based approach to preserve content privacy in Decentralized Online Social Networks
2020
Distributed Online Social Networks (DOSNs) have been proposed to shift the control over user data from a unique entity, the online social network provider, to the users of the DOSN themselves. In this paper we focus on the problem of preserving the privacy of the contents shared to large groups of users. In general, content privacy is enforced by encrypting the content, having only authorized parties being able to decrypt it. When efficiency has to be taken into account, new solutions have to be devised that: i) minimize the re-encryption of the contents published in a group when the composition of the group changes; and, ii) enable a fast distribution of the cryptographic keys to all the m…
A comparative thermogravimetric study of waterlogged archaeological and sound woods
2010
Waterlogged archaeological woods Pinus pinaster and Fagus sylvatica L. were analyzed by using TG technique. Degradation processes ascribable to the holocellulose decay were evidenced at nearly the same temperature for sound and archaeological samples. The residual matters at 600 and 900 °C of the sound woods are much lower than those of archaeological waterlogged woods in agreement with the presence of inorganic materials encapsulated during the burial into the marine environment. It was proposed a new protocol to rapidly calculate the maximum water content parameter, which is related to the wood degradation state. TG experiments at variable heating rates were performed to obtain kinetic pa…
Water Absorption of Hemp Fibre Nonwovens Modified with Metal and Metal Oxide Nanoparticles
2015
In this paper changes of ability of hemp fibre nonwovens to absorb water after deposition of metal and metal oxide nanoparticles were investigated. Moisture content of samples after storage in different climatic conditions was determined using thermogravimetric method. The obtained results were compared with the results of previous research based on investigation of water absorption of metalized woven fabric of bast fibre. Analysis of measurements showed that nonwoven samples with surface treated in plasma attract water slightly better than sample with untreated surface; this was more pronounced in woven fabric samples. In turn, metal coatings reduced water sorption. Unlike woven fabric sam…
Influence of drying to the structure of lactitol monohydrate
1997
The purpose of this study is to find out the effect of the crystal water content on the crystal structure of lactitol monohydrate. Crystal water was removed by drying over silicagel at 40°C and by using phosphorus pentoxide as drying agent at 20°C. The amouts of water removals were identified by thermogravimetry, the melting points and the heat of fusions were calculated from the results of differential scanning calorimetry measurements and the structure of samples were identified by X-ray powder diffraction method. Over 23 w/w% of total water content could removed by gently drying until significant structural changes could be detected. The melting point of anhydrous lactitol obtained by dr…
A novel dynamic multi-model relevance feedback procedure for content-based image retrieval
2016
This paper deals with the problem of image retrieval in large databases with a big semantic gap by a relevance feedback procedure. We present a novel algorithm for modelling the users's preferences in the content-based image retrieval system.The proposed algorithm considers the probability of an image belonging to the set of those sought by the user, and estimates the parameters of several local logistic regression models whose inputs are the low-level image features. A Principal Component Analysis method is applied to the original vector to reduce its high dimensionality. The relevance probabilities predicted by these local models are combined by means of a weighted average. These weights …
Evaluation of an Educational Video Production Environment
2019
In this paper, a cloud-based solution for the easy production and meaningful distribution of video-based learning material is presented and evaluated. Using this system, lecturers can produce video material with their own computers anywhere, at any time. The system enables the production of longer lecture videos as well as short videos, each containing only one of the course's topics. The system also handles video sharing for students automatically in a meaningful way through the course's table of contents. An evaluation of the first production version of the video production and distribution system was carried out by collecting qualitative material from the lecturers and students.