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2019 Other Open Access

Martinelli M., Bastiani L., Paolicchi F.
Una introduzione alle radiazioni - Materiale per Bright 2019

See at: ISTI Repository | CNR ExploRA

2019 Contribution to conference Open Access

Lo Stile di Vita del Frequentatore della Montagna
Martinelli M., Bastiani L., Valoti P., Agazzi G., Carrara B., Parigi G. B., Marina Malannino M., Spinelli A., Calderoli A., Orizio L., Righi M., Pardini F., Benassi A., D'Angelo G., Giardini G., Moroni D., Mrakic Sposta S., Pratali L.
La variazione dei frequentatori della montagna degli ultimi anni sta significativamente cambiando le problematiche del territorio montano: se da un lato aumenta il numero delle presenze temporanee (turisti, lavoratori, etc...), dall'altro diminuisce quello degli abitanti. Il primo, tra le varie, sta elevando il Male Acuto di alta Montagna (MAM) a problema di salute pubblica non trascurabile; il secondo porta ad una minore gestione del territorio generando problemi diretti ed indiretti, tra questi, favorito altresì dal riscaldamento globale, anche la proliferazione delle zecche. Questa ricerca ha esaminato in particolare I fattori di rischio individuale relativo allo stile di vita e al MAM.Source: XXI CONVEGNO NAZIONALE SIMeM, Arabba, 28/09/2019

See at: ISTI Repository | CNR ExploRA

2019 Contribution to conference Open Access

Bastiani L., Salvadori S., Martinelli M., Moroni D., Paolicchi F., Caramella D.
Nel corso degli ultimi decenni stiamo assistendo ad una rapida evoluzione delle tecniche di indagine radiologica, al fine di fornire prestazioni sempre più elevate e performanti. Il frequente e sistematico ricorso alle tecniche di diagnostica per immagini ha fatto sì che queste abbiano assunto il ruolo di strumento indispensabile per definire il corretto percorso terapeutico dei pazienti. Tutte queste metodiche tuttavia, se da un lato aumentano la capacità diagnostica delle procedure, dall'altro possono tendere ad esporre il paziente ad elevate quantità di radiazioni ionizzanti. Spesso il luogo comune associa alla parola "radiazioni" qualcosa di pericoloso. Limitata è però la consapevolezza relativa a quante radiazioni vengono impiegate per le diverse procedure diagnostiche e a quante ciascun individuo è quotidianamente esposto anche a causa del fondo naturale di radiazione.Source: BRIGHT 2019, 27/09/2019

See at: ISTI Repository | CNR ExploRA

2019 Other Unknown

Martinelli M., Bastiani L., Paolicchi F., Salvetti O., Caramella D.
Aggiornamento del Sito web per il progetto "Conoscenze della popolazione sui rischi delle procedure radiologiche" dedicato alla raccolta e alla elaborazione dei dati per la valutazione delle conoscenze della popolazione in merito ai rischi delle procedure radiologiche e alla comprensione delle corrette modalità con cui comunicare tali rischi ai pazienti. Versione 1.3_4 del 2019-12-20

2019 Contribution to book Open Access

Challenges in community discovery on temporal networks
Cazabet R., Rossetti G.
Community discovery is one of the most studied problems in network science. In recent years, many works have focused on discovering communities in temporal networks, thus identifying dynamic communities. Interestingly, dynamic communities are not mere sequences of static ones; new challenges arise from their dynamic nature. Despite the large number of algorithms introduced in the literature, some of these challenges have been overlooked or little studied until recently. In this chapter, we will discuss some of these challenges and recent propositions to tackle them. We will, among other topics, discuss of community events in gradually evolving networks, on the notion of identity through change and the ship of Theseus paradox, on dynamic communities in different types of networks including link streams, on the smoothness of dynamic communities, and on the different types of complexity of algorithms for their discovery. We will also list available tools and libraries adapted to work with this problem.Source: Temporal Network Theory, edited by Holme P.; Saramäki J., pp. 181–197, 2019
DOI: 10.1007/978-3-030-23495-9_10

2019 Contribution to conference Open Access

Male acuto di montagna: una app per test di autovalutazione
Martinelli M., Giardini G., Bastiani L., Agazzi G. C., Mrakic Sposta S., Pratali L.
Una applicazione sul Male Acuto di Montagna per il frequentatore delle montagneSource: XXI CONVEGNO NAZIONALE SIMeM 2019, Arabba, 28/9/2019

See at: ISTI Repository | CNR ExploRA

2019 Conference article Open Access

Modelling string structure in vector spaces
Connor R., Dearle A., Vadicamo L.
Searching for similar strings is an important and frequent database task both in terms of human interactions and in absolute worldwide CPU utilisation. A wealth of metric functions for string comparison exist. However, with respect to the wide range of classification and other techniques known within vector spaces, such metrics allow only a very restricted range of techniques. To counter this restriction, various strategies have been used for mapping string spaces into vector spaces, approximating the string distances within the mapped space and therefore allowing vector space techniques to be used. In previous work we have developed a novel technique for mapping metric spaces into vector spaces, which can therefore be applied for this purpose. In this paper we evaluate this technique in the context of string spaces, and compare it to other published techniques for mapping strings to vectors. We use a publicly available English lexicon as our experimental data set, and test two different string metrics over it for each vector mapping. We find that our novel technique considerably outperforms previously used technique in preserving the actual distance.Source: 27th Italian Symposium on Advanced Database Systems, Castiglione della Pescaia, Italy, 16-19/06/2019

2019 Report Open Access

SoBigData - D10.10 - Resource adaptation to register to the e-infrastructure 3
Assante M., Candela L., Manghi P., Pagano P.
Deliverable D10.10 "Resource adaptation to register to the e-infrastructure 3" is the revised version of the Deliverable D10.9 "Resource adaptation to register to the e-infrastructure 2" and Deliverable D10.8 "Resource adaptation to register to the e-infrastructure 1" intended to report the experiences of partners from different infrastructures at integrating their services, methods, and applications as SoBigData resources. The first section describes the general integration patterns, while the second section reports the experiences from the individual partners, revealing the effort required, in terms of time and technical complexity, and earned benefits. This revised version of the document covers the whole period of the project, including the up to date information of the D10.9 deliverable and the new experiences of partners at integrating their services, methods, and applications as SoBigData resources, developed through the project's lifetime.Source: Project report, SoBigData, Deliverable D10.10, pp.1–26, 2019
Project(s): SoBigData

2019 Report Open Access

SoBigData - D10.7 - SoBigData e-infrastructure and VRE release
Assante M., Candela L., Cirillo R., Frosini L., Lelii L., Mangiacrapa F., Pagano P.
This deliverable describes the software that has been deployed to serve the needs of the SoBigData community, by delivering the platform and the VREs planned in "D10.4 SoBigData e-Infrastructure release plan 3". In particular, it reports on how such software has been exploited to make available the envisaged components, i.e. the SoBigData portal (and the underlying Virtual Organisation), the SoBigData Catalogue and the SoBigData Virtual Research Environments, together with the list and pointers to the software packages produced by the project and implementing such components, whose operation today constitutes the SoBigData e-infrastructure accessible from http://sobigdata.d4science.org.Source: Project report, SoBigData, Deliverable D10.7, pp.1–28, 2019
Project(s): SoBigData

2019 Report Open Access

Towards Ontology-based Explainable Classification of Rare Events
Cardillo F. A., Straccia U.
Rare events (e.g. major floods, violent conflicts) are events that have potentially widespread and/or disastrous impact on society. The overall goal is to build a framework capable to classify, predict and explain such rare events. To do so, we envisage the usage of a mixture of sub-symbolic Machine Learning (ML) and Ontology-based Statistical Relatio-nal Learning (OSRL) techniques to generate rare events classifiers and predictors, which additionally may be mapped into natural language to ease human interpretability of the decision process.Source: ISTI Working papers, pp.1–2, 2019

2019 Journal article Open Access

Modal analysis of masonry structures
Girardi M., Padovani C., Pellegrini D.
This paper presents a new numerical tool for evaluating the vibration frequencies and mode shapes of masonry buildings in the presence of cracks. The algorithm has been implemented within the NOSA-ITACA code, which models masonry as a nonlinear elastic material with zero tensile strength. Some case studies are reported, and the differences between linear and nonlinear behaviour are highlighted.Source: Mathematics and mechanics of solids 24 (2019): 616–636. doi:10.1177/1081286517751837
DOI: 10.1177/1081286517751837

2019 Journal article Open Access

Fast and backward stable computation of the eigenvalues and eigenvectors of matrix polynomials
Aurentz J., Mach T., Robol L., Vandebril R., Watkins D. S.
In the last decade matrix polynomials have been investigated with the primary focus on adequate linearizations and good scaling techniques for computing their eigenvalues and eigenvectors. In this article we propose a new method for computing a factored Schur form of the associated companion pencil. The algorithm has a quadratic cost in the degree of the polynomial and a cubic one in the size of the coefficient matrices. Also the eigenvectors can be computed at the same cost. The algorithm is a variant of Francis's implicitly shifted QR algorithm applied on the companion pencil. A preprocessing unitary equivalence is executed on the matrix polynomial to simultaneously bring the leading matrix coefficient and the constant matrix term to triangular form before forming the companion pencil. The resulting structure allows us to stably factor each matrix of the pencil as a product of k matrices of unitary-plus-rank-one form, admitting cheap and numerically reliable storage. The problem is then solved as a product core chasing eigenvalue problem. A backward error analysis is included, implying normwise backward stability after a proper scaling. Computing the eigenvectors via reordering the Schur form is discussed as well. Numerical experiments illustrate stability and efficiency of the proposed methods.Source: Mathematics of computation (Online) 88 (2019): 313–347. doi:10.1090/mcom/3338
DOI: 10.1090/mcom/3338
Project(s): FUNCOMP

2019 Journal article Open Access

A fuzzy ontology-based approach for tool-supported decision making in architectural design
Di Noia T., Mongiello M., Nocera F., Straccia U.
In software development, Non-Functional Requirements (NFRs) play a crucial role in decision making procedures for architectural solutions. A strong relation exists between NFRs and design patterns, a powerful method to support the architectural design of software systems, but due to their complexity and abstraction, NFRs are rarely taken into account in software design. In fact, the knowledge on NFRs is usually owned by designers and not formalized in a structured way. We propose to structure the knowledge associated to NFRs via a Fuzzy Ontology, which we show is able to model their mutual relations and interactions. The declarative approach makes possible to represent and maintain the above mentioned knowledge by keeping the flexibility and fuzziness of modeling thanks to the use of fuzzy concepts such as high, low, fair, etc. We present a decision support system based on (i) a Fuzzy OWL 2 ontology that encodes 109 design patterns, 28 pattern families and 37 NFRs and their mutual relations, (ii) a novel reasoning service to retrieve a ranked list of pattern sets able to satisfy the Non-Functional Requirements within a system specification.Source: Knowledge and Information Systems 58 (2019): 83–112. doi:10.1007/s10115-018-1182-1
DOI: 10.1007/s10115-018-1182-1

2019 Journal article Open Access

Estimation of the spatial chromatin structure based on a multiresolution bead-chain model
Caudai C., Salerno E., Zoppe M., Tonazzini A.
We present a method to infer 3D chromatin configurations from Chromosome Conformation Capture data. Quite a few methods have been proposed to estimate the structure of the nuclear DNA in homogeneous populations of cells from this kind of data. Many of them transform contact frequencies into Euclidean distances between pairs of chromatin fragments, and then reconstruct the structure by solving a distance-to-geometry problem. To avoid inconsistencies, our method is based on a score function that does not require any frequency-to-distance translation. We propose a multiscale chromatin model where the chromatin fibre is suitably partitioned at each scale. The partial structures are estimated independently, and connected to rebuild the whole fibre. Our score function consists in a data-fit part and a penalty part, balanced automatically at each scale and each subchain. The penalty part enforces "soft" geometric constraints. As many different structures can fit the data, our sampling strategy produces a set of solutions with similar scores. The procedure contains a few parameters, independent of both the scale and the genomic segment treated. The partition of the fibre, along with intrinsically parallel parts, make this method computationally efficient. Results from human genome data support the biological plausibility of our solutions.Source: IEEE/ACM transactions on computational biology and bioinformatics (Print) 16 (2019): 550–559. doi:10.1109/TCBB.2018.2791439
DOI: 10.1109/tcbb.2018.2791439

2019 Journal article Open Access

ChromStruct 4: a Python code to estimate the chromatin structure from Hi-C data
Caudai C., Salerno E., Zoppè M., Merelli I., Tonazzini A.
A method and a stand-alone Python(TM) code to estimate the 3D chromatin structure from chromosome conformation capture data are presented. The method is based on a multiresolution, modified-bead-chain chromatin model, evolved through quaternion operators in a Monte Carlo sampling. The solution space to be sampled is generated by a score function with a data-fit part and a constraint part where the available prior knowledge is implicitly coded. The final solution is a set of 3D configurations that are compatible with both the data and the prior knowledge. The iterative code, provided here as additional material, is equipped with a graphical user interface and stores its results in standard-format files for 3D visualization. We describe the mathematical-computational aspects of the method and explain the details of the code. Some experimental results are reported, with a demonstration of their fit to the data.Source: IEEE/ACM transactions on computational biology and bioinformatics (Online) 16 (2019): 1867–1878. doi:10.1109/TCBB.2018.2838669
DOI: 10.1109/tcbb.2018.2838669

2019 Journal article Open Access

A model-based framework for mobile apps customization through context-dependent rules
Manca M., Paternò F., Santoro C.
The advent of the Internet of Things and mobile applications has made the possible contexts of use more and more varied, and creates new challenges for user interface developers. Although model-based approaches aim to support the generation of applications for different implementation technologies, limited attention has been paid to how to exploit them for novel context-dependent applications. We present a model-based framework that allows developers to flexibly customize their mobile apps to react to events not foreseen in the initial versions. It is composed of an authoring environment supporting the definition of model-based descriptions and generating mobile apps from them. The authoring environment allows developers to enrich the dynamic behaviour of the generated applications through trigger-action rules. The resulting versions of the apps can provide customized behaviour according to the actual contexts of use. The authoring environment supports efficient development of such customizations. We show its potential by describing an example application, and report on a first test with developers.Source: Universal access in the information society (Print) 18 (2019): 1–17. doi:10.1007/s10209-018-0620-x
DOI: 10.1007/s10209-018-0620-x

2019 Journal article Open Access

Reliable M2M/IoT data delivery from FANETs via satellite
Bacco F. M., Colucci M., Gotta A., Kourogiorgas C., Panagopoulos A.
The use of Unmanned Aerial Vehicles (UAVs) is rising in several application fields. This work deals with the communication challenges in UAV swarms, or Flying Ad-Hoc Networks (FANET), when taking into account non-line-of sight scenarios. The use of satellites is a necessity in such operating conditions, thus this work provides architectural considerations and performance assessments when several FANETs share an uplink Random Access (RA) satellite channel, fed with M2M/IoT traffic generated from onboard sensors, to be reliably delivered to a remote ground destination.Source: International journal of satellite communications and networking (Online) 37 (2019): 331–342. doi:10.1002/sat.1274
DOI: 10.1002/sat.1274

2019 Conference article Open Access

Performance analysis of WebRTC-based video streaming over power constrained platforms
Bacco M., Catena M., De Cola T., Gotta A., Tonellotto N.
This work analyses the use of the Web Real-Time Communications (WebRTC) framework on resource-constrained platforms. WebRTC is a consolidated solution for real-time video streaming, and it is an appealing solution in a wide range of application scenarios. We focus our attention on those in which power consumption, size and weight are of paramount importance because of the so-called Size, Weight and Power (SWaP) requirements, such as the use case of Unmanned Aerial Vehicles (UAVs) delivering real-time video streams over WebRTC to peers on the ground. The testbed described in this work shows that the power consumption can be reduced by changing WebRTC default settings while maintaining comparable video quality.Source: Globecom 2018 - 2018 IEEE Global Communications Conference, Abu Dhabi, United Arab Emirates, 9-13 December 2018
DOI: 10.1109/glocom.2018.8647375
DOI: 10.5281/zenodo.2705727
DOI: 10.5281/zenodo.2705728
Project(s): BigDataGrapes

2019 Journal article Open Access

Quasi-Toeplitz matrix arithmetic: a MATLAB toolbox
Bini D. A., Massei S., Robol L.
Quasi Toeplitz (QT) matrix is a semi-infinite matrix of the kind $A=T(a)+E$ where $T(a)=(a_{j-i})_{i,j\in\mathbb Z^+}$, $E=(e_{i,j})_{i,j\in\mathbb Z^+}$ is compact and the norms $\lVert a\rVert_{\mathcal W} = \sum_{i\in\mathbb Z}|a_i|$ and $\lVert E \rVert_2$ are finite. These properties allow to approximate any QT-matrix, within any given precision, by means of a finite number of parameters. QT-matrices, equipped with the norm $\lVert A \rVert_{\mathcal QT}=\alpha\lVert a\rVert_{\mathcal{W}} \lVert E \rVert_2$, for $\alpha = (1+\sqrt 5)/2$, are a Banach algebra with the standard arithmetic operations. We provide an algorithmic description of these operations on the finite parametrization of QT-matrices, and we develop a MATLAB toolbox implementing them in a transparent way. The toolbox is then extended to perform arithmetic operations on matrices of finite size that have a Toeplitz plus low-rank structure. This enables the development of algorithms for Toeplitz and quasi-Toeplitz matrices whose cost does not necessarily increase with the dimension of the problem. Some examples of applications to computing matrix functions and to solving matrix equations are presented, and confirm the effectiveness of the approach.Source: Numerical algorithms 81 (2019): 741–769. doi:10.1007/s11075-018-0571-6
DOI: 10.1007/s11075-018-0571-6

2019 Contribution to book Open Access

Factoring block Fiedler Companion Matrices
Del Corso G. M., Poloni F., Robol L., Vandebril R.
When Fiedler published his "A note on Companion matrices" in 2003 in Linear Algebra and its Applications, he could not have foreseen the significance of this elegant factorization of a companion matrix into essentially two-by-two Gaussian transformations, which we will name \emph{(scalar) elementary Fiedler factors}. Since then, researchers extended these results and studied the various resulting linearizations, the stability of Fiedler companion matrices, factorizations of block companion matrices, Fiedler pencils, and even looked at extensions to non-monomial bases. In this chapter, we introduce a new way to factor block Fiedler companion matrices into the product of scalar elementary Fiedler factors. We use this theory to prove that, e.g., a block (Fiedler) companion matrix can always be written as the product of several scalar (Fiedler) companion matrices. We demonstrate that this factorization in terms of elementary Fiedler factors can be used to construct new linearizations. Some linearizations have notable properties, such as low band-width, or allow for factoring the coefficient matrices into unitary-plus-low-rank matrices. Moreover, we will provide bounds on the low-rank parts of the resulting unitary-plus-low-rank decomposition. To present these results in an easy-to-understand manner we rely on the flow-graph representation for Fiedler matrices recently proposed by Del Corso and Poloni in Linear Algebra and its Applications, 2017.Source: edited by Bini, Dario; Di Benedetto, Fabio; Tyrtyshnikov, Eugene; Van Barel, Marc, pp. 129–155. Berlin: Springer International Publishing AG, 2019
DOI: 10.1007/978-3-030-04088-8_7