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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

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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

Semantic typing of linked geoprocessing workflows

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International Journal of Digital Earth 2018年第1期11卷 113-138页

作者： Simon Scheider andrea Ballatore Human Geography and Spatial Planning Universiteit UtrechtUtrechtNetherlands Department of Geography BirkbeckUniversity of LondonLondonUK

In Geographic Information Systems(GIS),geoprocessing workflows allow analysts to organize their methods on spatial data in complex *** propose a method for expressing workflows as linked data,and for semi-automatically enriching them with semantics on the level of their operations and *** workflows can be easily published on the Web and queried for types of inputs,results,or ***,GIS analysts can reuse their workflows in a modular way,selecting,adapting,and recommending resources based on compatible semantic *** typing approach starts from minimal annotations of workflow operations with classes of GIS tools,and then propagates data types and implicit semantic structures through the workflow using an OWL typing scheme and SPARQL rules by backtracking over GIS *** method is implemented in Python and is evaluated on two real-world geoprocessing workflows,generated with Esri's *** illustrate the potential applications of our typing method,we formulate and execute competency questions over these workflows.

关键词： Geoprocessing spatial analysis workflows semantic typing linked data

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

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Movement Primitives as a Robotic Tool to Interpret Trajectories Through Learning-by-doing

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International Journal of Automation and computing 2013年第5期10卷 375-386页

作者： andrea Soltoggio Andre Lemme Research Institute for Cognition and Robotics Bielefeld University

Articulated movements are fundamental in many human and robotic *** humans can learn and generalise arbitrarily long sequences of movements,and particularly can optimise them to ft the constraints and features of their body,robots are often programmed to execute point-to-point precise but fxed *** study proposes a new approach to interpreting and reproducing articulated and complex trajectories as a set of known robot-based *** of achieving accurate reproductions,the proposed approach aims at interpreting data in an agent-centred fashion,according to an agent s primitive *** method improves the accuracy of a reproduction with an incremental process that seeks frst a rough approximation by capturing the most essential features of a demonstrated *** the discrepancy between the demonstrated and reproduced trajectories,the process then proceeds with incremental decompositions and new searches in sub-optimal parts of the *** aim is to achieve an agent-centred interpretation and progressive learning that fts in the frst place the robots capability,as opposed to a data-centred decomposition *** on both geometric and human generated trajectories reveal that the use of own primitives results in remarkable robustness and generalisation properties of the *** particular,because trajectories are understood and abstracted by means of agent-optimised primitives,the method has two main features： 1） Reproduced trajectories are general and represent an abstraction of the data.2） The algorithm is capable of reconstructing highly noisy or corrupted data without pre-processing thanks to an implicit and emergent noise suppression and feature *** study suggests a novel bio-inspired approach to interpreting,learning and reproducing articulated movements and *** applications include drawing,writing,movement generation,object manipulation,and other tasks where the performance

关键词： Movement primitives learning pattern matching trajectory decomposition perception

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