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Assessment of seismic ground motion amplification and liquefaction at a volcanic area characterized by residual soils

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Journal of Mountain Science 2020年第3期17卷 740-752页

作者： Luca MATASSONI andrea FIASCHI Fondazione Parsec Via Galcianese20/H59100 PratoItaly(former)now at CittaMetropolitana di FirenzeDirezione Progetti StrategiciVia Cavour150129 FirenzeItaly Fondazione Parsec Via Galcianese20/H59100 PratoItaly

A seismic hazard was assessed related to site effects at Abbadia San Salvatore, central Italy, on the Mt. Amiata slopes, an ancient volcanic area characterized by residual soils(thick layers of loose to dense sands originated from weathering of the trachydacitic lavas). The seismic ground amplification and soil liquefaction related to these layers were recognized as the major seismic hazards for the ***, geophysical, and geotechnical surveys were carried out on the volcanic rocks. The Horizontal-to-Vertical Spectral Ratio(HVSR) analysis of 252 noise measurements and 29 shear-wave velocity models of the subsoil allowed a seismic microzonation of the studied area, distinguished by thick weathered volcanic sands and shear-wave impedance contrast with respect to the seismic bedrock(volcanic bedrock). The differentiation of classified zones allowed recognition of areas characterized by residual(almost undisturbed) soils from those with soils probably affected by flowing water. The analysis of hazards revealed that peak acceleration by seismic amplification of ground motion exceeded the value set by the national rules(0.175 g) in a restricted area of the zone characterized by the most perturbed soils(Zone D);the potential occurrence of soil liquefaction was also greater in this zone. Finally, the study showed potential high hazards due to site effects of the volcanic mountainous area characterized by residual soils as opposed to an alluvial plain formed by volcanic debris where these effects have generally been more recognized.

关键词： Site effects Residual soils Volcanic mountain area Seismic ground amplification Soil liquefaction Shear wave velocity

A NEW APPROXIMATION ALGORITHM FOR THE MATCHING DISTANCE IN MULTIDIMENSIONAL PERSISTENCE

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Journal of Computational Mathematics 2020年第2期38卷 291-309页

作者： andrea Cerri Patrizio Frosini FST-Fom Software Technology Italy Dipartimento di Matematica Universita di BolognaItaly

Topological Persistence has proven to be a promising framework for dealing with problems concerning shape analysis and *** this contexts,it was originally introduced by taking into account 1-dimensional properties of shapes,modeled by real-valued *** recently,Topological Persistence has been generalized to consider multidimensional proper ties of shapes,coded by vect or-valued *** extension has led to int roduce suitable shape descrip tors,named the multidimensional persis tence Betti numbers functions,and a distance to compare them,the so-called multidimensional matching *** this paper we propose a new computational framework to deal with the multidimensional matching *** start by proving some new theoretical results,and then we use them to formulate an algorithm for computing such a distance up to an arbitrary threshold error.

关键词： Multidimensional persistent topology Matching distance Shape comparison.

Options for continuous radar Earth observations

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Science China(Information Sciences) 2017年第6期60卷 7-21页

作者： andrea MONTI GUARNIERI Fabio ROCCA Dipartimento di Elettronica Informazione e Bioingegneria-Politecnico di Milano

Near Real Time(minutes or hours) radar imaging of ground targets located anywhere on an hemisphere, with or without interferometric coherence with previous passes, can be obtained with different solutions that are considered here. Geosynchronous systems, from the one proposed in 1978 by Tomiyasu to telecom satellite compatible solutions, and Low, Medium or Geosynchronous Earth Orbit constellations are *** benefits, problems, and sizes are briefly summarized, and a comparative table is presented. If interferometric coherence is requested, continuous imaging is obtained only if a very wide geostationary aperture is progressively scanned, eventually using a MIMO(Multiple Input Multiple Output) combination of several slow librating small satellites. Instead, fast librating, strip mapping, large geosynchronous satellites do provide high resolution imaging, but interferometry(and thus coherent change detection) is achievable only after a minimum delay of 12 h, i.e., when the target comes in sight without need to squint the antenna. Hence, both complex and simple systems reach full resolution interferometric imaging and thus coherent change detection capability only after 12 h.

关键词： synthetic aperture radar continuous Earth observing system geosynchronous systems

AuxSens,a FRET-based auxin biosensor

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Molecular Plant 2021年第7期14卷 1051-1052页

作者： andrea Tagliani Department of Biosciences Universita degli Studi di Milano-La Statale20133 MilanItaly

The effects of the plant hormone auxin have been widely studied over many *** regulates diverse processes in plants,and auxin signaling is known to play key roles in both plant development and plant response to environmental cues(Paque and Weijers,2016).To date,most of the reports dealing with perturbations of auxin signaling relied on auxin sensors based on transcriptional readouts(i.e.,changes in the output level of the reporter due to transcriptional effects of auxins).These sensors,mostly based on the DR5 or the Dll reporter systems,have enabled broad characterization of auxin distributions under various developmental or stress conditions.

关键词： FRET auxin dealing

Computed tomography colonography in 2014:An update on technique and indications

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World Journal of Gastroenterology 2014年第45期20卷 16858-16867页

作者： andrea Laghi Department of Radiological Sciences Oncology and Pathology Sapienza - Università di Roma I.C.O.T.Hospital

Twenty years after its introduction, computed tomographic colonography (CTC) has reached its maturity, and it can reasonably be considered the best radiological diagnostic test for imaging colorectal cancer (CRC) and polyps. This examination technique is less invasive than colonoscopy (CS), easy to perform, and standardized. Reduced bowel preparation and colonic distention using carbon dioxide favor patient compliance. Widespread implementation of a new image reconstruction algorithm has minimized radiation exposure, and the use of dedicated software with enhanced views has enabled easier image interpretation. Integration in the routine workflow of a computer-aided detection algorithm reduces perceptual errors, particularly for small polyps. Consolidated evidence from the literature shows that the diagnostic performances for the detection of CRC and large polyps in symptomatic and asymptomatic individuals are similar to CS and are largely superior to barium enema, the latter of which should be strongly discouraged. Favorable data regarding CTC performance open the possibility for many different indications, some of which are already supported by evidence-based data: incomplete, failed, or unfeasible CS; symptomatic, elderly, and frail patients; and investigation of diverticular disease. Other indications are still being debated and, thus, are recommended only if CS is unfeasible: the use of CTC in CRC screening and in surveillance after surgery for CRC or polypectomy. In order for CTC to be used appropriately, contraindications such as acute abdominal conditions (diverticulitis or the acute phase of inflammatory bowel diseases) and surveillance in patients with a long-standing history of ulcerative colitis or Crohn’s disease and in those with hereditary colonic syndromes should not be overlooked. This will maximize the benefits of the technique and minimize potential sources of frustration or disappointment for both referring clinicians and patients.

关键词： Computed tomographic colonography Virtual colonoscopy Computed tomographic colonography technique Computed tomographic colonography neoplasm Computed tomographic colonography polyp Computed tomographic colonography indications Computed tomographic colonography colorectal cancer screening Computed tomographic colonography diverticular disease Computed tomographic colonography surveillance

Detection and Localization of Load Redistribution Attacks on Large-scale Systems

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Journal of Modern Power Systems and Clean Energy 2022年第2期10卷 361-370页

作者： andrea Pinceti Lalitha Sankar Oliver Kosut the School of Electrical Computer and Energy EngineeringArizona State UniversityTempeUSA

A nearest-neighbor-based detector against load redistribution attacks is *** detector is designed to scale from small-scale to very large-scale systems while guaranteeing consistent detection *** testing is performed on a realistic large-scale system to evaluate the perfor-mance of the proposed detector against a wide range of attacks,from simple random noise attacks to sophisticated load redistribution *** detection capability is analyzed against different attack parameters to evaluate its sensitivity.A statistical test that leverages the proposed detector is introduced to identify which loads are likely to have been maliciously modified,thus,localizing the attack *** test is based on ascribing to each load a risk measure(probability of being attacked)and then computing the best posterior likelihood that minimizes log-loss.

关键词： Attack detection cyber-security false data injection(FDI)attack load redistribution attack machine learning nearest neighbor

Comparison Between Deep Learning Models and Traditional Machine Learning Approaches for Facial Expression Recognition in Ageing Adults

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Journal of Computer Science & Technology 2020年第5期35卷 1127-1146页

作者： andrea Caroppo Alessandro Leone Pietro Siciliano Institute for Microelectronics and Microsystems National Research Council of ItalyLecce 73100Italy

Facial expression recognition is one'of the most active areas of research in computer vision since one of the non-verbal communication methods by which one understands the lnood/mental state of a person is the expression of ***,it has been used in various fields such as human-robot interaction,security,computer graphics animation,and ambient ***,it remains a challenging task since existing approaches lack generalizability and almost all studies ignore the effects of facial attributes,such as *** expression recognition even though the research indicates that facial expression inanifestation varies with ***,a lot of progress has been made in this topic and great improvements in classification task were achieved with the emergence of deep learning *** approaches have sliown how hierarchies of features can be directly learned from original data,thus avoiding classical hand designed feature extraction methods that generally rely on manual operations witli labelled ***,research papers systematically exploring tlu4 performance of existing deep architectures for the task of classifying expression of ageing adults are absent in the *** the present work a tentative to try this gap is done considering the performance of three recent deep convolutiorial neural networks models(VGG-16,AlexNet and GoogLeNet/Inception V1)and evaluating it on four different benchmark datcisets(FACES,Lifespan,CIFE,and FER2013)which also contain facial expressions performed by elderly *** the baseline,and with the aim of making a comparison,two traditional inacliine learning approaches based on handcrafted features extraction process are evaluated on the same *** out an exhaustive and rigorous experimentation focused on the concept of "transfer learning",which consists of replacing the output level of the deep architectures considered with new output levels appropriate to the number of classes(facial expressions),

关键词： computer vision deep learning facial expression machine learning ageing adult

Tree colonization by the Asian longhorn beetle, Anoplophora glabripennis （Coleoptera： Cerambycidae）： effect of habitat and tree suitability

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Insect Science 2016年第2期23卷 288-296页

作者： Massimo Faccoli Riccardo Favaro Giuseppe Concheri andrea Squartini andrea Battisti Department of Agronomy Food Natural resources Animals and Environment (DAFNAE) University of Padova Legnaro (PD) Italy

Tree colonization and feeding activity of the invasive wood-borer Asian longhorn beetle （Anoplophora glabripennis）, an Asian pest introduced into North America and Europe, was studied in a newly invaded area in Italy. The hypothesis be- ing tested was that the reproductive success of the insect depend on habitat type and tree suitability. Adult beetles were caged on branches of host and nonhost species, in both urban and forest habitats. Two months later, number and size of feeding patches on plant tissues, eggs laid, and surviving larvae were assessed. Bark concentration of C and N was also measured from the same trees. Results indicated that the mean area of plant tissues consumed by adult feeding was significantly larger on trees growing in forest than in urban habitat, although within the same habitat there were no differences between susceptible and nonsusceptible trees. ALB tree colonization, in terms of number of eggs laid and young larvae survival, was not affected by habitat while it was higher on susceptible trees. Although trees growing in forests had a lower nitrogen concentration, they allowed colo- nization rates similar to those of trees growing in the urban habitat. Hence, the amount of carbon and nitrogen did not fully explain tree suitability or habitat selection. We suggest compensatory feeding as a potential mechanism that might explain this peculiar situation, as supported by a more intensive feeding activity recorded on trees in the forest. Suitability of different trees may be due to other factors, such as secondary chemical compounds.

关键词： Asian longhorn beetle performance breeding feeding forest nonhost urban

Limiting majoron self-interactions from gravitational wave experiments

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Chinese Physics C 2018年第2期42卷 64-70页

作者： andrea Addazi Antonino Marcianò Department of Physics & Center for Field Theory and Particle Physics Fudan University

We show how majoron models may be tested/limited in gravitational wave experiments. In particular,the majoron self-interaction potential may induce a first order phase transition, producing gravitational waves from bubble collisions. We dub such a new scenario the violent majoron model, because it would be associated with a violent phase transition in the early Universe. Sphaleron constraints can be avoided if the global U（1）_（B-L） is broken at scales lower than the electroweak scale, provided that the B-L spontaneously breaking scale is lower than10 TeV in order to satisfy the cosmological mass density bound. The possibility of a sub-electroweak phase transition is practically unconstrained by cosmological bounds and it may be detected within the sensitivity of the next generation of gravitational wave experiments： eLISA, DECIGO and BBO. We also comment on its possible detection in the next generation of electron-positron colliders, where majoron production can be observed from the Higgs portals in missing transverse energy channels.

关键词： lepton/baryon number violation majorons gravitational waves colliders