448 result(s)
Page Size: 10, 20, 50
Export: bibtex, xml, json, csv
Order by:

CNR Author operator: and / or
more
Typology operator: and / or
more
Language operator: and / or
Date operator: and / or
more
Rights operator: and / or
2018 Report Restricted

Ship Kinematics Estimation (SKE) module - Vessel kinematics estimation through SAR/Optical Imagery Processing
Reggiannini M., Bedini L.
The main goal of the work described in this report concerns the estimation of the kinematics variables related to the motion of a navigating vessel. One way to perform such operations is to process maps captured by Synthetic Aperture Radar (SAR) and optical sensors installed on board of satellite constellations orbiting around earth-centred trajectories. The primary goal of this processing is to identify and analyze the wake traces left by navigating vessels on the water surface. Wakes can be typically observed in high resolution SAR and optical maps. A proper processing of these surface patterns allows to estimate the orientation of the vessel motion ({\it route}) and the corresponding velocity module. The resulting estimates can be exploited in the implementation of maritime surveillance and vessel traffic monitoring purposes. This document describes the design and the implementation of the software procedures dedicated to the aforementioned purposes, together combined in the software tool named Ship Kinematics Estimation module.Source: ISTI Technical Reports, 2018

See at: CNR ExploRA Restricted


2018 Report Open Access OPEN

SoBigData - D10.9 - Resource adaptation to register to the e-infrastructure 2
Assante M., Candela L., Manghi P., Pagano P.
Deliverable D10.9 "Resource adaptation to register to the e-infrastructure 2" is the revised version of the D10.8 deliverable "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 D10.8 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 D10.9, pp.1–23, 2018
Project(s): SoBigData via OpenAIRE

See at: data.d4science.net Open Access | ISTI Repository Open Access | CNR ExploRA Open Access


2018 Journal article Embargo

Business process flexibility - a systematic literature review with a software systems perspective
Cognini R., Corradini F., Gnesi S., Polini A., Re B.
Business Process flexibility supports organizations in changing their everyday work activities to remain competitive. Since much research has been done on this topic a better awareness on the current state of knowledge is needed. This paper reports the results of a systematic literature review to develop a map on Business Process flexibility with a special focus on software systems related aspects. It covers a spectrum of the state of the art from academic point of view. It includes 164 research works from the main computer science digital libraries. After an introduction into the topic the applied methodology is described. The output of the paper is in the form of schemes and reflections. Starting from the needs for Business Process flexibility, its impact on Business Process life-cycle is introduced. Successively instruments used to express and to support Business Process flexibility are presented together with related validation scenarios. In this paper we also highlight possible future research lines needing further investigations. In particular we identified room for future works in the area of languages for modeling flexibility, on-the-fly verification solutions, adaptation of Business Process running instances, and techniques for evolution recognition.Source: Information systems frontiers (Print) 20 (2018): 343–371. doi:10.1007/s10796-016-9678-2
DOI: 10.1007/s10796-016-9678-2

See at: Information Systems Frontiers Restricted | Information Systems Frontiers Restricted | Information Systems Frontiers Restricted | Information Systems Frontiers Restricted | Information Systems Frontiers Restricted | link.springer.com Restricted | Information Systems Frontiers Restricted | Information Systems Frontiers Restricted | Information Systems Frontiers Restricted | Information Systems Frontiers Restricted | Information Systems Frontiers Restricted | CNR ExploRA Restricted


2018 Journal article Open Access OPEN

Beyond trans-dimensional RJMCMC with a case study in impulsive data modeling
Karakus O., Kuruoglu E. E., Altinkaya M. A.
Reversible jump Markov chain Monte Carlo (RJMCMC) is a Bayesian model estimation method, which has been generally used for trans-dimensional sampling and model order selection studies in the literature. In this study, we draw attention to unexplored potentials of RJMCMC beyond trans-dimensional sampling. the proposed usage, which we call trans-space RJMCMC exploits the original formulation to explore spaces of different classes or structures. This provides flexibility in using different types of candidate classes in the combined model space such as spaces of linear and nonlinear models or of various distribution families. As an application, we looked into a special case of trans-space sampling, namely trans-distributional RJMCMC in impulsive data modeling. In many areas such as seismology, radar, image, using Gaussian models is a common practice due to analytical ease. However, many noise processes do not follow a Gaussian character and generally exhibit events too impulsive to be successfully described by the Gaussian model. We test the proposed usage of RJMCMC to choose between various impulsive distribution families to model both synthetically generated noise processes and real-life measurements on power line communications impulsive noises and 2-D discrete wavelet transform coefficients. (C) 2018 Elsevier B.V. All rights reserved.Source: Signal processing (Print) 153 (2018): 396–410. doi:10.1016/j.sigpro.2018.07.028
DOI: 10.1016/j.sigpro.2018.07.028
Project(s): PTDC/EEA-TEL/67979/2006 via OpenAIRE

See at: Aperta TÜBİTAK Open Archive Open Access | arXiv.org e-Print Archive Open Access | DSpace@IZTECH Open Access | DSpace@IZTECH Open Access | Signal Processing Open Access | ISTI Repository Open Access | Signal Processing Restricted | Signal Processing Restricted | Signal Processing Restricted | Signal Processing Restricted | Signal Processing Restricted | Signal Processing Restricted | Signal Processing Restricted | Signal Processing Restricted | Signal Processing Restricted | CNR ExploRA Restricted | research-information.bris.ac.uk Restricted | Signal Processing Restricted | Signal Processing Restricted | Signal Processing Restricted | Signal Processing Restricted | Signal Processing Restricted | Signal Processing Restricted


2018 Conference article Open Access OPEN

UAVs and UAV swarms for civilian applications: communications and image processing in the SCIADRO project
Bacco M., Chessa S., Di Benedetto M., Fabbri D., Girolami M., Gotta A., Moroni D., Pascali M. A., Pellegrini V.
The use of Unmanned Aerial Vehicles (UAVs), or drones, is increasingly common in both research and industrial fields. Nowadays, the use of single UAVs is quite established and several products are already available to consumers, while UAV swarms are still subject of research and development. This position paper describes the objectives of a research project, namely SCIADRO2, which deals with innovative applications and network architectures based on the use of UAVs and UAV swarms in several civilian fields.Source: WiSATS 2017 - International Conference on Wireless and Satellite Systems, pp. 115–124, Oxford, UK, 14-15 September 2017
DOI: 10.1007/978-3-319-76571-6_12

See at: ISTI Repository Open Access | academic.microsoft.com Restricted | link.springer.com Restricted | link.springer.com Restricted | CNR ExploRA Restricted | rd.springer.com Restricted


2018 Contribution to book Open Access OPEN

How data mining and machine learning evolved from relational data base to data science
Amato G., Candela L., Castelli D., Esuli A., Falchi F., Gennaro C., Giannotti F., Monreale A., Nanni M., Pagano P., Pappalardo L., Pedreschi D., Pratesi F., Rabitti F., Rinzivillo S., Rossetti G., Ruggieri S., Sebastiani F., Tesconi M.
During the last 35 years, data management principles such as physical and logical independence, declarative querying and cost-based optimization have led to profound pervasiveness of relational databases in any kind of organization. More importantly, these technical advances have enabled the first round of business intelligence applications and laid the foundation for managing and analyzing Big Data today.Source: A Comprehensive Guide Through the Italian Database Research Over the Last 25 Years, edited by Sergio Flesca, Sergio Greco, Elio Masciari, Domenico Saccà, pp. 287–306, 2018
DOI: 10.1007/978-3-319-61893-7_17

See at: Archivio della Ricerca - Università di Pisa Open Access | ISTI Repository Open Access | academic.microsoft.com Restricted | arpi.unipi.it Restricted | dblp.uni-trier.de Restricted | link.springer.com Restricted | link.springer.com Restricted | link.springer.com Restricted | CNR ExploRA Restricted | rd.springer.com Restricted


2018 Journal article Open Access OPEN

Efficient Ehrlich-Aberth iteration for finding intersections of interpolating polynomials and rational functions
Robol L., Vandebril R.
We analyze the problem of carrying out an efficient iteration to approximate the eigenvalues of some rank structured pencils obtained as linearization of sums of polynomials and rational functions expressed in (possibly different) interpolation bases. The class of linearizations that we consider has been introduced by Robol, Vandebril and Van Dooren in [17]. We show that a traditional QZ iteration on the pencil is both asymptotically slow (since it is a cubic algorithm in the size of the matrices) and sometimes not accurate (since in some cases the deflation of artificially introduced infinite eigenvalues is numerically difficult). To solve these issues we propose to use a specifically designed Ehrlich-Aberth iteration that can approximate the eigenvalues in O(kn²) flops, where k is the average number of iterations per eigenvalue, and n the degree of the linearized polynomial. We suggest possible strategies for the choice of the initial starting points that make k asymptotically smaller than O(n), thus making this method less expensive than the QZ iteration. Moreover, we show in the numerical experiments that this approach does not suffer of numerical issues, and accurate results are obtained.Source: Linear algebra and its applications 542 (2018): 282–309. doi:10.1016/j.laa.2017.05.010
DOI: 10.1016/j.laa.2017.05.010

See at: Linear Algebra and its Applications Open Access | Archivio della Ricerca - Università di Pisa Open Access | ISTI Repository Open Access | CNR ExploRA Open Access | Lirias Open Access | Linear Algebra and its Applications Restricted | Linear Algebra and its Applications Restricted | Linear Algebra and its Applications Restricted | Linear Algebra and its Applications Restricted | Linear Algebra and its Applications Restricted


2018 Journal article Open Access OPEN

Sleep behavior assessment via smartwatch and stigmergic receptive fields
Alfeo A., Barsocchi P., Cimino M., La Rosa D., Palumbo F., Vaglini G.
Sleep behavior is a key factor in maintaining good physiological and psychological health. A well-known approach to monitor sleep is polysomnography. However, it is costly and intrusive, which may disturb sleep. Consequently, polysomnography is not suitable for sleep behavior analysis. Other approaches are based on actigraphy and sleep diary. Although being a good source of information for sleep quality assessment, sleep diaries can be affected by cognitive bias related to subject's sleep perception, while actigraphy overestimates sleep periods and night-time disturbance compared to sleep diaries. Machine learning techniques can improve the objectivity and reliability of the observations. However, since signal morphology vary widely between people, conventional machine learning is complex to set up. In this regard, we present an adaptive, reliable, and innovative computational approach to provide per-night assessment of sleep behavior to the end-user. We exploit heartbeat rate and wrist acceleration data, gathered via smartwatch, in order to identify subject's sleep behavioral pattern. More specifically, heartbeat rate and wrist motion samples are processed via computational stigmergy, a bio-inspired scalar and temporal aggregation of samples. Stigmergy associates each sample to a digital pheromone deposit (mark) defined in a mono-dimensional space and characterized by evaporation over time. As a consequence, samples close in terms of time and intensity are aggregated into functional structures called trails. The stigmergic trails allow to compute the similarity between time series on different temporal scales, to support classification or clustering processes. The overall computing schema includes a parametric optimization for adapting the structural parameters to individual sleep dynamics. The outcome is a similarity between sleep nights of the same subject, to generate clusters of nights with different quality levels. Experimental results are shown for three real-world subjects. The resulting similarity is also compared with the dynamic time warping, a popular similarity measure for time series.Source: Personal and ubiquitous computing (Internet) 22 (2018): 227–243. doi:10.1007/s00779-017-1038-9
DOI: 10.1007/s00779-017-1038-9

See at: Archivio della Ricerca - Università di Pisa Open Access | ISTI Repository Open Access | Personal and Ubiquitous Computing Restricted | Personal and Ubiquitous Computing Restricted | Personal and Ubiquitous Computing Restricted | Personal and Ubiquitous Computing Restricted | Personal and Ubiquitous Computing Restricted | Personal and Ubiquitous Computing Restricted | Personal and Ubiquitous Computing Restricted | Personal and Ubiquitous Computing Restricted | CNR ExploRA Restricted


2018 Contribution to book Restricted

Quality evaluation for evolving conceptual database design
Locuratolo E. I.
The article is concerned with the proposal of a new approach of conceptual database design, called evolving conceptual database design, which exploits the structure for the preservation of database classes/concepts within the design. In order to discuss the opportunity to take into consideration this approach, the structure is constructed starting from a database conceptual graph. The leaves of the structure are mapped to a logical/object database graph. Horizontal steps of constructive logical database design extend the model. The computational costs required to design the structure for the preservation of database classes/concepts, as well as the qualitative/conceptual costs of the logical models resulting from the constructive design, are discussed.Source: Encyclopedia of Information Science and Technology, edited by Mehdi Khosrow-Pour, pp. 2020–2030. Hershey: IGI Global, 2018
DOI: 10.4018/978-1-5225-2255-3.ch175
DOI: 10.4018/978-1-5225-7598-6.ch046

See at: academic.microsoft.com Restricted | CNR ExploRA Restricted | www.igi-global.com Restricted | www.igi-global.com Restricted | www.igi-global.com Restricted | www.igi-global.com Restricted


2018 Contribution to book Restricted

Knowledge Acquisition on Dante Alighieri's works
Locuratolo E. I., Bartalesi Lenzi V.
The approach followed for the identification and the implementation of visualization diagrams able to support the knowledge acquisition on Dante's works is described. Educational aspects of mathematics and statistics underlying the histogram representations are proposed, and the approach to acquire knowledge on Dante's works, starting from visualization diagrams is described. The article is part of the Towards a Digital Dante Encyclopedia, a three-year Italian National Project.Source: Encyclopedia of Information Science and Technology, edited by Mehdi Khosrow-Pour, pp. 5067–5076. Hershey: IGI Global, 2018
DOI: 10.4018/978-1-5225-2255-3.ch439
DOI: 10.4018/978-1-5225-7659-4.ch030

See at: academic.microsoft.com Restricted | CNR ExploRA Restricted | www.igi-global.com Restricted | www.igi-global.com Restricted | www.igi-global.com Restricted | www.igi-global.com Restricted


2018 Journal article Open Access OPEN

Solvability and uniqueness criteria for generalized Sylvester-type equations
De Teran F., Iannazzo B., Poloni F., Robol L.
We provide necessary and sufficient conditions for the generalized (star operator)-Sylvester matrix equation, AXB+CX(star operator)D=E, to have exactly one solution for any right-hand side E. These conditions are given for arbitrary coefficient matrices A, B, C, D (either square or rectangular) and generalize existing results for the same equation with square coefficients. We also review the known results regarding the existence and uniqueness of solution for generalized Sylvester and (star operator)-Sylvester equations.Source: Linear algebra and its applications 542 (2018): 501–521. doi:10.1016/j.laa.2017.07.010
DOI: 10.1016/j.laa.2017.07.010

See at: arXiv.org e-Print Archive Open Access | Linear Algebra and its Applications Open Access | Archivio della Ricerca - Università di Pisa Open Access | ISTI Repository Open Access | Linear Algebra and its Applications Restricted | Linear Algebra and its Applications Restricted | Linear Algebra and its Applications Restricted | Linear Algebra and its Applications Restricted | CNR ExploRA Restricted | Linear Algebra and its Applications Restricted


2018 Journal article Open Access OPEN

A 3D-centered information system for the documentation of a complex restoration intervention
Apollonio F. I., Basilissi V., Callieri M., Dellepiane M., Gaiani M., Ponchio F., Rizzo F., Rubino A. R., Scopigno R., Sobrà G.
Restoration is becoming a quite complex process: a large number of internal and external variables co-exist and may impair it. Among these, the large number of professionals involved and the huge amount of documentation produced can heavily affect the quality of the intervention as well as the possibility to have systemic and informed interventions in the future. In particular, a standardized method for storing restoration data and accessing them is still lacking, and the use of new technologies is still limited and/or not scalable. The paper describes the process of designing and testing an information system (IS) based on three-dimensional (3D) data, aimed to support the restoration of Neptune's Fountain in Bologna. In preparation of the restoration, a major effort was carried out to design and implement a web-based IS able to host all of the data produced, to allow the conservation-restoration specialists to interact on-site with an accurate 3D representation of the elements of the fountain, and to directly reference all information and data produced on the geometry of the model. The paper focuses on the challenges and adopted solutions related to the use of 3D models and the data mapping on 3D surfaces in the context of restoration documentation. Highly detailed visualizations of the models, easy navigation, and usable functionalities to add information directly on the 3D model have been achieved by extending the available solutions and by implementing new mechanisms to overcome the limitations of WebGL and remote rendering. Neptune IS' development has been extensively experimented in a real context of use. Results and knowledge from the experimentation currently represents the basis for evolving Neptune IS into a possible generic and flexible platform for documentation management in the field of restoration and related methodologies.Source: Journal of cultural heritage 29 (2018): 89–99. doi:10.1016/j.culher.2017.07.010
DOI: 10.1016/j.culher.2017.07.010

See at: RE.PUBLIC@POLIMI Research Publications at Politecnico di Milano Open Access | ISTI Repository Open Access | Journal of Cultural Heritage Restricted | Journal of Cultural Heritage Restricted | Journal of Cultural Heritage Restricted | Journal of Cultural Heritage Restricted | Journal of Cultural Heritage Restricted | Archivio istituzionale della ricerca - Alma Mater Studiorum Università di Bologna Restricted | CNR ExploRA Restricted | Journal of Cultural Heritage Restricted | www.sciencedirect.com Restricted


2018 Journal article Open Access OPEN

On quadratic matrix equations with infinite size coefficients encountered in QBD stochastic processes
Bini D. A., Massei S., Meini B., Robol L.
Matrix equations of the kind $A_1 X^2 + A0 X + A_{-1} = X$, where both the matrix coefficients and the unknown are semi-infinite matrices belonging to a Banach algebra, are considered. These equations, where coefficients are quasi-Toeplitz matrices, are encountered in certain quasi-birth-death processes as the tandem Jackson queue or in any other processes that can be modeled as a reflecting random walk in the quarter plane. We provide a numerical framework for approximating the minimal nonnegative solution of these equations that relies on semi-infinite quasi-Toeplitz matrix arithmetic. In particular, we show that the algorithm of cyclic reduction can be effectively applied and can approxi- mate the infinite-dimensional solutions with quadratic convergence at a cost that is comparable to that of the finite case. This way, we may compute a finite approximation of the sought solution and of the invariant probability measure of the associated quasi-birth-death process, within a given accuracy. Numerical experiments, performed on a collection of benchmarks, confirm the theoretical analysis.Source: Numerical linear algebra with applications (Online) 25 (2018). doi:10.1002/nla.2128
DOI: 10.1002/nla.2128

See at: Numerical Linear Algebra with Applications Open Access | Archivio della Ricerca - Università di Pisa Open Access | Infoscience - EPFL scientific publications Open Access | ISTI Repository Open Access | Numerical Linear Algebra with Applications Restricted | Numerical Linear Algebra with Applications Restricted | Numerical Linear Algebra with Applications Restricted | Numerical Linear Algebra with Applications Restricted | Numerical Linear Algebra with Applications Restricted | Numerical Linear Algebra with Applications Restricted | onlinelibrary.wiley.com Restricted | Numerical Linear Algebra with Applications Restricted | CNR ExploRA Restricted


2018 Journal article Open Access OPEN

Aggregating binary local descriptors for image retrieval
Amato G., Falchi F., Vadicamo L.
Content-Based Image Retrieval based on local features is computationally expensive because of the complexity of both extraction and matching of local feature. On one hand, the cost for extracting, representing, and comparing local visual descriptors has been dramatically reduced by recently proposed binary local features. On the other hand, aggregation techniques provide a meaningful summarization of all the extracted feature of an image into a single descriptor, allowing us to speed up and scale up the image search. Only a few works have recently mixed together these two research directions, defining aggregation methods for binary local features, in order to leverage on the advantage of both approaches.In this paper, we report an extensive comparison among state-of-the-art aggregation methods applied to binary features. Then, we mathematically formalize the application of Fisher Kernels to Bernoulli Mixture Models. Finally, we investigate the combination of the aggregated binary features with the emerging Convolutional Neural Network (CNN) features. Our results show that aggregation methods on binary features are effective and represent a worthwhile alternative to the direct matching. Moreover, the combination of the CNN with the Fisher Vector (FV) built upon binary features allowed us to obtain a relative improvement over the CNN results that is in line with that recently obtained using the combination of the CNN with the FV built upon SIFTs. The advantage of using the FV built upon binary features is that the extraction process of binary features is about two order of magnitude faster than SIFTs.Source: Multimedia tools and applications 77 (2018): 5385–5415. doi:10.1007/s11042-017-4450-2
DOI: 10.1007/s11042-017-4450-2
Project(s): EAGLE

See at: arXiv.org e-Print Archive Open Access | Multimedia Tools and Applications Open Access | ISTI Repository Open Access | Multimedia Tools and Applications Restricted | Multimedia Tools and Applications Restricted | Multimedia Tools and Applications Restricted | Multimedia Tools and Applications Restricted | Multimedia Tools and Applications Restricted | Multimedia Tools and Applications Restricted | Multimedia Tools and Applications Restricted | CNR ExploRA Restricted


2018 Conference article Open Access OPEN

How blind people can manage a remote control system: a case study
Buzzi M., Gennai F., Leporini B.
Remote Control Systems (RCSs) are increasingly being installed in homes and offices. Technology evolves very rapidly and sensors and devices are becoming smaller, smarter and more powerful. Mobile and Web apps are commonly used to remotely configure and control devices. Home control is especially valuable for blind people, since they can benefit from technology to control and turn on/off devices autonomously. Remote control can offer meaningful support, especially when devices are not directly accessible (e.g,. thermostat to manage heating temperature). Therefore, if RCS interfaces are not accessible via screen reader, blind users may miss a great opportunity to achieve greater autonomy at home. This paper investigates the accessibility of the web user interfaces offered by RCSs for blind people. To do this, the Fibaro, a popular Remote Control System, was tested as a case study by analyzing the interaction via screen reader. Results indicate that accessibility and especially usability need to be improved to make interaction easier and more satisfying for blind people. To this aim, some suggestions are offered to aid developers in designing more accessible RCS user interfaces.Source: GOODTECHS 2017 - International Conference on Smart Objects and Technologies for Social Good, pp. 71–81, Pisa, Italy, 29-30 November 2017
DOI: 10.1007/978-3-319-76111-4_8

See at: ISTI Repository Open Access | academic.microsoft.com Restricted | dblp.uni-trier.de Restricted | link.springer.com Restricted | link.springer.com Restricted | CNR ExploRA Restricted | rd.springer.com Restricted


2018 Journal article Open Access OPEN

Modeling reliable M2M/IoT traffic over random access satellite links in non-saturated conditions
Bacco F. M., Cassarà P., Colucci M., Gotta A
Nowadays, Machine-to-Machine and Internet of Things traffic sources puts the terrestrial networks under great pressure. While 5G is still on its way, satellites are used to deliver a fraction of such an enormous traffic rate. In this work, we investigate the use of the Constrained Application Protocol to reliably deliver Machine-to-Machine and Internet of Things traffic in a push fashion, which also implements a Selective Repeat Automatic Repeat reQuest and a sender-based variant of the TCP Friendly Rate Control protocol. We aim at providing an analytical model to evaluate the working point of the system in non-saturated conditions as a function of the MAC parameters in use, when such a closed-loop congestion control mechanism is in use over a random access satellite channel. The proposed analytical model is then validated against simulation results, showing a good precision.Source: IEEE journal on selected areas in communications (Print) 36 (2018): 1042–1051. doi:10.1109/JSAC.2018.2832799
DOI: 10.1109/jsac.2018.2832799
Project(s): SATNEX

See at: ISTI Repository Open Access | IEEE Journal on Selected Areas in Communications Restricted | IEEE Journal on Selected Areas in Communications Restricted | ieeexplore.ieee.org Restricted | IEEE Journal on Selected Areas in Communications Restricted | CNR ExploRA Restricted | IEEE Journal on Selected Areas in Communications Restricted


2018 Conference article Open Access OPEN

A survey on network architectures and applications for nanosat and UAV swarms
Bacco F. M., Cassarà P., Colucci M., Gotta A., Marchese M., Patrone F.
Nanosatellites and unmanned aerial vehicles are attracting more and more the interest of both industrial and research fields. They are low-cost and easy deployable items, therefore their use is expected to quickly grow in the next few years. This work proposes a survey on the network architectures and the applications for nanosatellite swarms and constellations, as well as for flying ad hoc networks, by character- izing distinctive features and issues yet to be resolved in order to take advantage from both technologies in a joint fashion.Source: WiSATS 2017 - International Conference on Wireless and Satellite Systems, pp. 75–85, Oxford, UK, 14-15 September 2017
DOI: 10.1007/978-3-319-76571-6_8

See at: ISTI Repository Open Access | academic.microsoft.com Restricted | link.springer.com Restricted | link.springer.com Restricted | link.springer.com Restricted | CNR ExploRA Restricted | rd.springer.com Restricted


2018 Journal article Open Access OPEN

The influence of environmental parameters on the dynamic behaviour of the San Frediano bell tower in Lucca
Azzara R. M., De Roeck G., Girardi M., Padovani C., Pellegrini D., Reynders E.
This paper aims at assessing the influence of environmental parameters on the modal characteristics of age-old masonry constructions. The results of a long-term ambient vibration monitoring of the San Frediano bell tower in Lucca (Italy) are reported. The tower, dating back to the 11th century, has been fitted along its height with four triaxial seismometric stations, which were left active for about one year. Data from the monitoring system have been processed via the Stochastic Subspace Identification Method in order to identify the tower's modal characteristics and their variations over the year. The dependence of the tower's frequencies on the ambient temperature was first studied and simulated via simple auto-regressive models. Then, some output-only models based on the principal component analysis (PCA) were applied, under the hypotheses of both linear and nonlinear (Kernel PCA) dependence of the natural frequencies on the unknown environmental parameters. The results indicate PCA to be an effective tool for detecting changes in the dynamic characteristics of masonry constructions.Source: Engineering structures 156 (2018): 175–187. doi:10.1016/j.engstruct.2017.10.045
DOI: 10.1016/j.engstruct.2017.10.045

See at: Engineering Structures Open Access | Lirias Open Access | ISTI Repository Open Access | Engineering Structures Restricted | Engineering Structures Restricted | Engineering Structures Restricted | Engineering Structures Restricted | CNR ExploRA Restricted | Engineering Structures Restricted | www.sciencedirect.com Restricted


2018 Contribution to book Open Access OPEN

Analysing trajectories of mobile users: from data warehouses to recommender systems
Nardini F. M., Orlando S., Perego R., Raffaetà A., Renso C., Silvestri C.
This chapter discusses a general framework for the analysis of trajectories of moving objects, designed around a Trajectory Data Warehouse (TDW). We argue that data warehouse technologies, combined with geographic visual analytics tools, can play an important role in granting very fast, accurate and understandable analysis of mobility data. We describe how in the last decade the TDW models have changed in order to provide the user with a more suitable model of the reality of interest and we also cope with the challenge of semantic trajectories. As a use case we illustrate how the framework can be instantiated for realizing a recommender system for tourists.Source: A Comprehensive Guide Through the Italian Database Research Over the Last 25 Years, edited by Sergio Flesca, Sergio Greco, Elio Masciari, Domenico Saccà, pp. 407–421, 2018
DOI: 10.1007/978-3-319-61893-7_24

See at: ISTI Repository Open Access | academic.microsoft.com Restricted | dblp.uni-trier.de Restricted | iris.unive.it Restricted | link.springer.com Restricted | link.springer.com Restricted | CNR ExploRA Restricted | rd.springer.com Restricted


2018 Journal article Open Access OPEN

Synthetic aperture radar processing for vessel kinematics estimation
Reggiannini M., Bedini L.
Navigating vessels leave traces of their motion in the form of wake patterns on the water surface. Wakes are visible in high resolution Synthetic Aperture Radar maps and bear information related to the kinematic variables of the vessel motion. A proper processing of the wake pattern allows to estimate the vessel heading and velocity. This information can be exploited in decision procedures concerning maritime surveillance and ship traffic monitoring. This document describes the design and implementation of software procedures with the purpose of estimating the motion parameters of a navigating vessel, through processing the wake pattern generated by the vessel itself.Source: Proceedings (MDPI) 2 (2018). doi:10.3390/proceedings2020091
DOI: 10.3390/proceedings2020091
DOI: 10.5281/zenodo.1159154
DOI: 10.5281/zenodo.1159153

See at: Proceedings Open Access | Proceedings Open Access | Proceedings Open Access | ISTI Repository Open Access | CNR ExploRA Open Access | Proceedings Open Access | Proceedings Open Access | ZENODO Open Access