3,924 research outputs found
Portraits of Leonardo da Vinci
No full textUsing an iterative method, applied to image processing, a portrait of a young man, probably a self-portrait of Leonardo da Vinci, is restored. Merging this portrait with the self-portrait in red chalk, we can have the features of a middle-aged Leonardo. This digital portrait can be compared with the image of Plato, depicted by Raphael in the Scuola di Atene, generally considered as a portrait of Leonardo. The iterative method used for the image processing had been developed by the author on previous iterative calculations used to solve the Boltzmann equatio
Monitoring of Cultural Heritage Buildings in Seismic Area
No full textArchitectural heritage groups a wide number of historical constructions such as churches, towers,
buildings, bridges, and fortresses, and all of them represent a focal point of the community’s cultural
identity. Along the centuries, indeed, a series of actions have been done to preserve their integrity and
consequently to enhance the value of the cultural heritage for humanity.
Unfortunately, as stated in [Doglioni et al. 1994] [3], [Canuti et al. 2016] [1], [Despotaki et al. 2018]
[2], and [Pavia et al. 2021] [4], such architectural cultural heritage is characterized by both structural
and typological vulnerabilities often responsible of their poor performance to actions related to
extreme events, like earthquakes, being it usually designed for gravity actions. Therefore, the analysis
of the seismic vulnerabilities represents a relevant step for choosing and designing proper retrofitting
and preservation strategies.
An integrated approach is required to know these sources of vulnerability, and different disciplines
provide essential contributions: historic investigations of the construction evolution; geometric and
material surveys of the constructions; in situ experimental testing and characterization of the
materials; structural modelling and seismic analysis. Given the intrinsic difficulties that structural
engineers must face when modelling heritage buildings, non-invasive experimental testing methods
are valuable tools to provide support in the identification of the structural characteristics of a building.
Among the various possibilities for non-invasive experimental tests, this PhD thesis refers to these
ones that can characterize the response of the structure under service conditions, commonly referred
as Operational Analysis (OA). As common practice these tests are separated in dynamic and static
tests. Regarding dynamic tests, the technique and methodology of Operational Modal Analysis
(OMA), e.g. [Brinker and Ventura – 2015] [5], [Ranieri and Fabbrocino – 2014] [6], is a very effective
tool for structural identification and for model updating to support model-based simulations for the
prediction of the seismic response of heritage constructions as well as for the calibrations of advanced
seismic upgrading interventions. As regards instead the static tests, e.g. [Kita et all. 2018] [37],
[Cavalagli et all. 2017] [43], [Ramos et all. 2012] [38] and [Lorenzoni et all. 2015] [44], together
with the dynamic tests, they give a better interpretation of how the structure has been behaves under
earthquakes or extreme events making in light the deficiency of the structural system in order to make
a more realistic finite element model (FEM) of the structure.
In a wider comprehensive view, these analysis techniques provide a better knowledge of the structural
response of cultural heritage in their operational conditions, helping in characterizing their seismic response by the evaluation of the modal properties’ changes (i.e., dynamic response), and in
characterizing the evolution of kinematic mechanisms such as the over-turning mechanisms (i.e.,
static response). These results, inside the optical of structural health monitoring, can make in light
outcomes both in modal properties and in displacement measures that can suggest potentials
phenomenon of damage that may arise.
For this reason, the design of embedded monitoring systems that provide either a real-time and
periodic information about the structural integrity and performance is a necessary activity to provide
an insight on the structural health state of cultural heritage and to characterise the seismic response. This PhD Thesis seeks to design an embedded monitoring system that acquire both dynamic physical
and static quantities to identify the structural response over-time, either in operational conditions, and
during seismic events including potentially destructive ones, to develop an automatic data analysis
process that assesses the properties that describe the response of the structure such as modal properties
which natural frequencies, modal shapes and modal damping integrated with static monitoring
measures such as displacement measured across the cracks.
The innovative procedures developed within this work aims at automatically selecting the seismic
evets input that can give a modification on the structural response within the data acquired through
continuous monitoring, exploiting information available from the Italian National Institute of
Geophysics and Volcanology (INGV) relevant to seismic events.
Specifically, the objectives of this PhD thesis are:
• to select the most effective monitoring system by considering specific problems concerning
historical buildings and the available post processing data techniques to automize the analysis
process.
• to set up a real-time process that continuously acquire data from different types of sensors and
save them in a cloud server for the successive analyses.
• to select the seismic events occurred that may have changed the structural response, evaluating
the in site expected shaking intensity through a calibration of a specific attenuation law based
on data available from Italian National Institute of Geophysics and Volcanology (INGV)
relevant to seismic events.to develop a tool that processes the acquired data using an efficient
identification algorithm coupled with a clustering analysis. • to validate the developed tools in two case-studies the Portico da Varano of Ducal Palace, and
the Santa Maria in Via Church, both located in the city of Camerino, severely stroked by the
2016 central Italy seismic sequence
Introduzione. «Arti di pinna»: Leonardo Sciascia Saggista
No full textThe article presents the main theme of the XIV Sciascia Colloquium - the essay form explored by Leonardo Sciascia in his works - discussing each contribution and the focus each author chose to develop for this volume publication
Dutch space; interview with Arnaud de Jong, CEO
No full textDutch Space, the largest space company in the Netherlands and part of Airbus Defence and Space, appointed a new CEO last year. The Leonardo Times sat down with the CEO Arnaud de Jong for an interview. We discuss his career, developments in Dutch Space, his take on competition in the commercial space domain and his future outlook on European and International space markets.Aerospace Engineerin
Airborne aerospace; interview with business development manager space
No full textAirborne Composites designs and manufactures composite parts for the Aerospace, Oil & Gas, Marine and other industries since 1995. They are involved in notable hightech projects, from the Galileo Satellites, to the Gulfstream aircraft for Fokker and the ALMA astronomical telescope. The Leonardo Times sat down to talk to Sandor Woldendorp, Business Development Manager, Space division at Airborne to get an insight in the question: ‘’How do they do it?’’.Aerospace Engineerin
Crisis of Parties and Change of Party System in Italy
No full textLeonardo Morlino. Is there a crisis of democracy in Southern Europe? 30 cm. This paper is based partly on a seminar entitled Is there a crisis of democracy in Southern Europe?" presented at the Center on November 16, 1995" - T.p. Includes bibliographical references (p. 30-32
Digital Extensions with Bi-axial Fingertip Sensors for Supplementary Tactile Feedback Studies
No full textModeling as a critical process of knowledge. Survey of buildings in a state of ruin
No full textHBIM modeling presupposes a series of methodological and content questions depending on the type of historic building being investigated. A particular case refers to a multitude of buildings,
isolated or aggregated, that sprinkle our territory that do not stand out for their valuable architectural characteristics abandoned for different reasons and turned to ruins. This building category retains a
valuable judgment when the typological constructive characteristics are recognized as explanations of “making architecture”, strongly linked to a place and to a time and that are worth preserving.
The study of a ruin as a building typology involves various issues starting from the survey, bothin terms of structure stability and room accessibility, and in terms of survey techniques to be used
to acquire geometries that have lost their original conformation. The loss and deformation of the shape are therefore the main obstacles in the reconstruction of the historical evolutionary phases,
fundamental for the definition of a recovery project that respects the nature of the building, now in a state of instability. Informed digital models, soon mandatory by law in most building processes,
applied to the ruins thus become not only a means of documenting, cataloging, and communicating the built heritage but, above all, a tool that serves the project
Citizen of space: Living in orbit
No full textAn interpretation of the inspiring symposium organised by de VSV 'Leonardo da Vinci'Aerospace Engineerin
Why (and how) to regulate Power Exchanges in the EU market integration context?
No full textPower Exchanges (PXs) are key market institutions in open and market-based electricity industries. This paper aims at contributing to the ongoing debate on why and how to regulate Power Exchanges in the EU market integration context. . The paper starts by stating that two different types of PXs have to be distinguished, i.e. "Merchant" PXs and the "Cost of Service Regulated" PXs. The paper continues by comparing the typical incentives of these two types of PXs to perform the basic PX tasks in an isolated national market and in a market integration context. The paper concludes by deriving from this analytical frame the most relevant regulatory actions..Regulation, Exchanges, Grid access, Power Markets.
- …
