109 research outputs found
Automatically evaluating the quality of textual descriptions in cultural heritage records
AbstractMetadata are fundamental for the indexing, browsing and retrieval of cultural heritage resources in repositories, digital libraries and catalogues. In order to be effectively exploited, metadata information has to meet some quality standards, typically defined in the collection usage guidelines. As manually checking the quality of metadata in a repository may not be affordable, especially in large collections, in this paper we specifically address the problem of automatically assessing the quality of metadata, focusing in particular on textual descriptions of cultural heritage items. We describe a novel approach based on machine learning that tackles this problem by framing it as a binary text classification task aimed at evaluating the accuracy of textual descriptions. We report our assessment of different classifiers using a new dataset that we developed, containing more than 100K descriptions. The dataset was extracted from different collections and domains from the Italian digital library "Cultura Italia" and was annotated with accuracy information in terms of compliance with the cataloguing guidelines. The results empirically confirm that our proposed approach can effectively support curators (F1
∼
0.85) in assessing the quality of the textual descriptions of the records in their collections and provide some insights into how training data, specifically their size and domain, can affect classification performance
Automatically evaluating the quality of textual descriptions in cultural heritage records
Metadata are fundamental for the indexing, browsing and retrieval of cultural heritage resources in repositories, digital libraries and catalogues. In order to be effectively exploited, metadata information has to meet some quality standards, typically defined in the collection usage guidelines. As manually checking the quality of metadata in a repository may not be affordable, especially in large collections, in this paper we specifically address the problem of automatically assessing the quality of metadata, focusing in particular on textual descriptions of cultural heritage items. We describe a novel approach based on machine learning that tackles this problem by framing it as a binary text classification task aimed at evaluating the accuracy of textual descriptions. We report our assessment of different classifiers using a new dataset that we developed, containing more than 100K descriptions. The dataset was extracted from different collections and domains from the Italian digital library \u201cCultura Italia\u201d and was annotated with accuracy information in terms of compliance with the cataloguing guidelines. The results empirically confirm that our proposed approach can effectively support curators (F1 3c 0.85) in assessing the quality of the textual descriptions of the records in their collections and provide some insights into how training data, specifically their size and domain, can affect classification performance
Assessing variability among culturable phylloplane basidiomycetous yeasts from Italian agroecosystems
This study analysed basidiomycetous yeasts isolated from the phylloplane of crops and spontaneous plants in Italian agroecosystems.
A total of 25 species belonging to 17 genera were recognized by analysing 83 isolates from vineyards and
orchards, that are not treated with synthetic fungicides, and adjacent natural areas. Rhodotorula graminis and Filobasidium
magnum were the most frequent species but 13 others were represented by a single isolate (e.g., Buckleyzyma salicina,
Pseudozyma prolifica, and Moniliella megachiliensis). Preliminary analysis of (GTG)5-PCR fingerprinting revealed high
genetic intraspecific heterogeneity. All isolates were characterized by their production of extracellular hydrolytic enzymes
and their sensitivity to six commercial fungicides used in Italy. The isolates displayed great variability in these phenotypic
traits, which play an important role in the survival of yeast populations in agroecosystems. Most of them exhibited
lipolytic, proteolytic, β-glucosidase and pectinolytic activities, but only three (F. magnum, Kwoniella mangroviensis and
Ps. prolifica) also had cellulolytic and amylolytic activity. Most isolates were sensitive to four fungicides, and one R.
graminis isolate was resistant to all six. This heterogeneity was not related to the geographical origin of the isolates. The
lack of selective factors (i.e. pesticide treatments) in the sampling fields and the presence of adjacent natural areas may
have favored the maintenance of an elevated level of strain diversity. This study provides new information on phylloplane
basidiomycetous yeasts in agroecosystems and opens the way to further investigations into the impact of agricultural
practices on the microbial diversity of these natural habitats
metadata and tools for integration and preservation of cultural heritage 3d information
In this paper we investigate many of the various storage, portability and interoperability issues arising among archaeologists and cultural heritage people when dealing with 3D technologies. On the one side, the available digital repositories look often unable to guarantee affordable features in the management of 3D models and their metadata; on the other side the nature of most of the available data format for 3D encoding seem to be not satisfactory for the necessary portability required nowadays by 3D information across different systems. We propose a set of possible solutions to show how integration can be achieved through the use of well known and wide accepted standards for data encoding and data storage. Using a set of 3D models acquired during various archaeological campaigns and a number of open source tools, we have implemented a straightforward encoding process to generate meaningful semantic data and metadata. We will also present the interoperability process carried out to integrate the encoded 3D models and the geographic features produced by the archaeologists. Finally we will report the preliminary (rather encouraging) development of a semantic enabled and persistent digital repository, where 3D models (but also any kind of digital data and metadata) can easily be stored, retrieved and shared with the content of other digital archives
Development of an Experimental/Numerical Validation Methodology for the Design of Exhaust Manifolds of High Performance Internal Combustion Engines
Several typical failure modes in the exhaust manifold of an internal combustion engine are commented on. In particular, thermal loading and the related thermal fatigue damage mechanism are addressed. The component under investigation is a cast exhaust manifold including the turbine involute. Finite Element simulations are performed, and a numerical methodology is presented to interpret and understand the observed failures, with the aim of developing a useful tool to virtually validate the component, before the manufacturing phase. The Finite Element analysis closely mimics the experimental validation procedure that considers several heating and rapid cooling cycles to simulate typical engine operating conditions. A static mechanical characterization at high temperatures of the materials involved is carried out, aimed at identifying a suitable alloy and its mechanical characteristics useful for feeding the numerical models. The developed design methodology proposes a damage criterion for thermal fatigue investigation, considering the elastoplastic behaviour of the material when subjected to high temperature cycles. In particular, the accumulated equivalent plastic strain range for a single thermal cycle (ΔPEEQ) is used, following the Ferrari expertise. The methodology appears to be well correlated with the experimental evidence, thus limiting the number of tests necessary for the approval of the component
The spontaneous immortalization probability of mammalian cell culture strains, as their proliferative capacity, correlates with species body mass, not longevity
Background: The Peto's paradox consists in the observation that individuals from long-lived and large animal species do not experience a higher cancer incidence, despite being exposed for longer time to the possibility of accumulating mutations and having more target cells exposed to the phenomenon. The existence of this paradox has been recently confirmed (Vincze et al., 2022). Concurrently, robust evidence has been published that longevity involves a convergent evolution of cellular mechanisms that prevent the accu-mulation of mutations (Cagan et al., 2022). It remains unclear which cellular mechanisms are critical to allow the evolution of a large body mass while keeping cancer at bay.Methods: Adding to existing data linking cellular replicative potential and species body mass (Lorenzini et al., 2005), we have grown a total of 84 skin fibroblast cell strains from 40 donors of 17 mammalian species and analyzed their Hayflick's limit, i.e., their senescent plateau, and eventual spontaneous immortalization escape. The correlation of immortal-ization and replicative capacity of the species with their longevity, body mass and meta-bolism has been assessed through phylogenetic multiple linear regression (MLR).Results: The immortalization probability is negatively related to species body mass. The new evaluation and additional data about replicative potential strengthen our previous observation, confirming that stable and extended proliferation is strongly correlated with the evolution of a large body mass rather than lifespan.Conclusion: The relation between immortalization and body mass suggests a need to evolve stringent mechanisms that control genetic stability during the evolution of a large body mass
A Cloud-based Vehicle Collision Avoidance Strategy for Unmanned Aircraft System Traffic Management (UTM) in Urban Areas
Unmanned Aircraft Systems are increasingly used to monitor and sense our cities and the diffusion of UAS will require a Traffic Management System to coordinate UAS in the low-altitude airspace. In this paper we propose a collision avoidance strategy to be implemented in an Unmanned Aircraft System Traffic Management (UTM). The proposed strategy relies on a Cloud-based architecture that monitors and manages the low-altitude airspace, as well as coordinating the fleet of UAS. The strategy uses a Priority-based Model Predictive Control approach to define the optimal trajectory of the UAS, avoiding obstacles and other UAS with higher priority. The optimal trajectory is shared with other UAS to communicate the own motion track to be avoided by other UAS.
The suggested method is implemented and tested in simulations with three UAS with conflicting trajectories. Preliminary results positively support the proposed approach
A Systematic Error in the Internal Friction Measurement of Coatings for Gravitational Waves Detectors
Low internal friction coatings are key components of advanced technologies
such as optical atomic clocks and high-finesse optical cavity and often lie at
the forefront of the most advanced experiments in Physics. Notably, increasing
the sensitivity of gravitational-wave detectors depends in a very large part on
developing new coatings, which entails developing more suitable methods and
models to investigate their loss angle. In fact, the most sensitive region of
the detection band in such detectors is limited by the coating thermal noise,
which is related to the loss angle of the coating. Until now, models which
describe only ideal physical properties have been adopted, wondering about the
use of one or more loss angles to describe the mechanical properties of
coatings. Here we show the presence of a systematic error ascribed to
inhomogeneity of the sample at its edges in measuring the coating loss angle.
We present a model for disk-shaped resonators, largely used in loss angle
measurements, and we compare the theory with measurements showing how this
systematic error impacts on the accuracy with which the loss model parameters
are known
Differences in cardiac phenotype and natural history of laminopathies with and without neuromuscular onset
Objective: To investigate differences in cardiac manifestations of patients affected by laminopathy, according to the presence or absence of neuromuscular involvement at presentation.Methods: We prospectively analyzed 40 consecutive patients with a diagnosis of laminopathy followed at a single centre between 1998 and 2017. Additionally, reports of clinical evaluations and tests prior to referral at our centre were retrospectively evaluated.Results: Clinical onset was cardiac in 26 cases and neuromuscular in 14. Patients with neuromuscular presentation experienced first symptoms earlier in life (11 vs 39 years; p < 0.0001) and developed atrial fibrillation/flutter (AF) and required pacemaker implantation at a younger age (28 vs 41 years [p = 0.013] and 30 vs 44 years [p = 0.086] respectively), despite a similar overall prevalence of AF (57% vs 65%; p = 0.735) and atrio-ventricular (A-V) block (50% vs 65%; p = 0.500). Those with a neuromuscular presentation developed a cardiomyopathy less frequently (43% vs 73%; p = 0.089) and had a lower rate of sustained ventricular tachyarrhythmias (7% vs 23%; p = 0.387). In patients with neuromuscular onset rhythm disturbances occurred usually before evidence of cardiomyopathy. Despite these differences, the need for heart transplantation and median age at intervention were similar in the two groups (29% vs 23% [p = 0.717] and 43 vs 46 years [p = 0.593] respectively).Conclusions: In patients with laminopathy, the type of disease onset was a marker for a different natural history. Specifically, patients with neuromuscular presentation had an earlier cardiac involvement, characterized by a linear and progressive evolution from rhythm disorders (AF and/or A-V block) to cardiomyopathy
Detecting the gravito-magnetic field of the dark halo of the Milky Way - the LaDaHaD mission concept
We propose to locate transponders and atomic clocks in at least three of the Lagrange points of the Sun-Earth pair, with the aim of exploiting the time of flight asymme- try between electromagnetic signals travelling in opposite directions along polygonal loops having the Lagrange points at their vertices. The asymmetry is due to the pres- ence of a gravito-magnetic field partly caused by the angular momentum of the Sun, partly originating from the angular momentum of the galactic dark halo in which the Milky Way is embedded. We list also various opportunities which could be associated with the main objective of this Lagrange Dark Halo Detector (LaDaHaD)
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