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Processing tools to separate out cavitation and machinery noise
No full textThe need to isolate the contributions due to machinery noise and cavitation noise has become an important issue to be dealt with to improve the understanding of the fundamental underlying mechanisms of propagation into the sea as well as to implement effective measures to mitigate their effects on the overall radiated noise. As both machinery noise and cavitation noise are in the same frequency region, straightforward signal processing techniques are practically inadequate and advanced methods are needed for the selective detection of the different noise sources. This is the major aim of Work Package 2.4. In particular, the objective of this task is to estimate the acoustic source strength of a cavitating propeller and to separate out the contributions due to machinery noise and cavitation noise using advanced signal processing techniques, in conjunction with Task 2.5. The research work within SONIC WP2 Task 2.4 "Processing tools to separate out cavitation and machinery noise" has been carried out by: ? CNR-INSEAN, Italy (Task Leader) ? MARIN, Netherlands and, specifically, it has concerned the following topics: 1. Parametric study of noise, hull pressure fluctuations and vibrations in a scaled model of the "Princess Royal" Research Vessel (CNR INSEAN). The activity concerned the execution of a parametric study based on noise and vibration measurements on a scaled model of the "Princess Royal" Research Vessel. Aim of the survey was to collect a comprehensive database of noise, pressure fluctuation and vibration measurements to be used for verifying the methodologies developed within Work packages 2.4 and 2.5. The parametric study concerned different combinations of model excitation, propeller installation and propeller cavitation. 2. Development of an advanced signal processing technique to separate out the contributions due to machinery noise and cavitation noise (CNR INSEAN). The approach consists of a spectral conditioning technique which allows the separation of the machinery noise contribution from "in-field" hydrophone or pressure signals, by removing the part correlated to "out-of-field" sensors located in correspondence of the engine room and of the driving system. 3. Application of a method for the computation of the underwater-radiated far-field noise due to propeller cavitation to the case of the \u27Princess Royal\u27 Research Vessel, at the blade rate frequency (MARIN). The method attempts to determine the far-field noise by determining the propeller\u27s acoustic source strength on the basis of near-field hull pressure measurements. The method is based on the inverse application of a panel method for acoustic scattering
Quarter .it n. 2 - settembre 2015
No full textIl Quarter .it nasce nel 2013 ed ? un supplemento della testata giornalistica registrata Focus. it. Il quadrimestrale del Registro .it raccoglie dati statistici e commenti relativi al quadrimestre dell\u27anno di riferimento di?registrazioni e tutte le attivit? correlate, di cui ci sia un dato rilevante da raccontare e di particolare rilievo. Allo stesso tempo raccoglie le news del Registro, progetti finanziati dall\u27anagrafe italiana dei domini Internet ed eventi.?Il quadrimestrale esce sia nella versione italiana che in quella inglese
Playing with geometry: a Multimodal Android App for Blind Children
No full textGeometry is a traditionally difficult subject to teach to visually impaired subjects. This paper investigates tools to help blind children learn geometry. An accessible vibro-tactile-based android application has been designed to allow children to make freehand drawings and play with geometry, recognizing common geometric shapes or topological configurations.An initial usability test of the application, performed by a blind researcher, has revealed some limitations of the proposed approach that could soon be overcome thanks to current technological innovation in the mobile world
Giochi didattici per l?apprendimento
Get PDFQuesto articolo descrive una piattaforma di giochi didattici per bambini con bisogni educativi speciali realizzata nell?ambito del progetto del MIUR ?La citt? Educante
"Internetopoli: un ambiente di apprendimento a misura di nativo digitale" in "Tuttoscuola n. 552"
No full textL\u27articolo ? dedicato all\u27applicazione multimediale Internetopoli, intesa come ambiente di apprendimento 2.0 ?dedicato alla Ret
A Linguistically-driven Approach to Cross-Event Damage Assessment of Natural Disasters from Social Media Messages
Get PDFThis work focuses on the analysis of Italian social media messages for disaster management and aims at the detection of messages carrying critical information for the damage assessment task. A main novelty of this study consists in the focus on out-domain and cross-event damage detection, and on the investigation of the most relevant tweet-derived features for these tasks. We devised different experiments by resorting to a wide set of linguistic features qualifying the lexical and grammatical structure of a text as well as ad-hoc features specifically implemented for this task. We investigated the most effective features that allow to achieve the best results. A further result of this study is the construction of the first manually annotated Italian corpus of social media messages for damage assessment
Linked Data Maps: Providing a Visual Entry Point for the Exploration of Datasets
No full textLinked Data sets are an ever-growing, invaluable source of information and knowledge. However, the wide adoption of this large amount of interlinked structured data is still held back by some non-trivial obstacles. The one we tackle in this article is the difficulty users have in getting started with their work on Linked Data sources. In fact, querying, and in general dealing with such datasets, requires a deep knowledge about their specific classes, instances and properties. We be- lieve that an entry point that eases the access to such information would significantly reduce the barriers around this technology and foster its promotion. Linked Data Maps is a method for representing RDF graphs as interactive, map-like visualizations, based on our previous work fo- cused on the visual exploration of DBpedia. The approach is extended to deal with a wider range of Linked Data sets, and tested with a user evaluation study on two distinct RDF graphs.
TRAP: using TaRgeted Ads to unveil Google personal Profiles
Get PDFIn the last decade, the advertisement market spread significantly in the web and mobile app system. Its effectiveness is also due thanks to the possibility to target the advertisement on the specific interests of the actual user, other than on the content of the website hosting the advertisement. In this scenario, became of great value services that collect and hence can provide information about the browsing user, like Facebook and Google. In this paper, we show how to maliciously exploit the Google Targeted Advertising system to infer personal information in Google user profiles. In particular, the attack we consider is external from Google and relies on combining data from Google AdWords with other data collected from a website of the Google Display Network. We validate the effectiveness of our proposed attack, also discussing possible application scenarios. The result of our research shows a significant practical privacy issue behind such type of targeted advertising service, and call for further investigation and the design of more privacy-aware solutions, possibly without impeding ?the current business model involved in online advertisement.
Business Reputation of Social Networks of Web Services
Get PDFThis paper introduces a set of criteria that are used to establish the reputation of a social network from a business perspective. This network is populated with social Web services. Compared to regular Web services, social Web services establish and maintain networks of contacts, count on their (privileged) contacts when needed, etc. These criteria are membershipCost, demandLevel, satisfactionLevel, and retentionLevel, and assist a social Web service in selecting the best social network in which it will sign up. Similar criteria have been defined in the past with emphasis on the security perspective of a social network. A set of simulations conducted over an in-house built JAVA testbed, are also presented in the paper with focus on analyzing three aspects: profit of network, quality of network, and profit?versus?quality of network
Differential Regulation of MicroRNAs in End-Stage Failing Hearts Is Associated with Left Ventricular Assist Device Unloading
Get PDFMechanical unloading by left ventricular assist devices (LVADs) in advanced heart failure (HF), in addition to improving symptoms and end-organ perfusion, is supposed to stimulate cellular and molecular responses which can reverse maladaptive cardiac remodeling. As microRNAs (miRNAs) are key regulators in remodeling processes, a comparative miRNA profiling in transplanted hearts of HF patients with/without LVAD assistance could aid to comprehend underlying molecular mechanisms. Next generation sequencing (NGS) was used to analyze miRNA differential expression in left ventricles of HF patients who underwent heart transplantation directly (n=9) or following a period of LVAD support (n=8). After data validation by quantitative real-time PCR, association with functional clinical parameters was investigated. Bioinformatics? tools were then used for prediction of putative targets of modulated miRNAs and relative pathway enrichment. The analysis revealed 13 upregulated and 10 downregulated miRNAs in failing hearts subjected to LVAD assistance. In particular, the expression level of some of them (miR-338-3p, miR-142-5p and -3p, miR-216a-5p, miR-223-3p, miR-27a-5p, and miR-378g) showed correlation with off-pump cardiac index values. Predicted targets of these miRNAs were involved in focal adhesion/integrin pathway and in actin cytoskeleton regulation. The identified miRNAs might contribute to molecular regulation of reverse remodeling and heart recovery mechanisms