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Deep Learning,Feature Learning,and Clustering Analysis for SEM Image Classification

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Data Intelligence 2020年第4期2卷 513-528页

作者： Rossella Aversa Piero Coronica Cristiano De Nobili stefano cozzini National Research Council-Istituto Officina dei Materiali(CNR-IOM) 34136 TriesteItaly KIT-Karlsruhe Institute of Technology Hermann-von-Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany Research Software Engineering University of CambridgeCambridge CB30FAUK Freelance at *** Area Science Park Padriciano 9934149 TriesteItaly

In this paper,we report upon our recent work aimed at improving and adapting machine learning algorithms to automatically classify nanoscience images acquired by the Scanning Electron Microscope(SEM).This is done by coupling supervised and unsupervised learning approaches.We first investigate supervised learning on a ten-category data set of images and compare the performance of the different models in terms of training accuracy.Then,we reduce the dimensionality of the features through autoencoders to perform unsupervised learning on a subset of images in a selected range of scales(from 1μm to 2μm).Finally,we compare different clustering methods to uncover intrinsic structures in the images.

关键词： Neural networks Feature learning Clustering analysis Scanning Electron Microscope(SEM) Image classification

Dependence of impact regime boundaries on the initial temperatures of projectiles and targets

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Defence Technology（防务技术） 2024年第1期31卷 49-57页

作者： stefano Signetti Andreas Heine Fraunhofer-Institut für Kurzzeitdynamik Ernst-Mach-InstitutEMIErnst-Zermelo-Str.479104 Freiburg im BreisgauGermany

Towards higher impact velocities,ballistic events are increasingly determined by the material temperatures.Related effects might range from moderate thermal softening to full phase transition.In particular,it is of great interest to quantify the conditions for incipient or full melting of metals during impact interactions,which result in a transition from still strength-affected to hydrodynamic material behavior.In this work,we investigate to which extent the respective melting thresholds are also dependent on the initial,and generally elevated,temperatures of projectiles and targets before impact.This is studied through the application of a model developed recently by the authors to characterize the transition regime between high-velocity and hypervelocity impact,for which the melting thresholds of materials were used as the defining quantities.The obtained results are expected to be of general interest for ballistic application cases where projectiles or targets are preheated.Such conditions might result,for example,from aerodynamic forces acting onto a projectile during atmospheric flight,explosive shapedcharge-jet formation or armor exposure to environmental conditions.The performed analyses also broaden the scientific understanding of the relevance of temperature in penetration events,generally known since the 1960s,but often not considered thoroughly in impact studies.

关键词： Ballistic impact Thermal effects Metallic targets Energy partitioning Homologous temperature

Physical exercise and traumatic brain injury: is it question of time?

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Neural Regeneration Research 2024年第3期19卷 475-476页

作者： Valentina Mastrorilli stefano Farioli Vecchioli Institute of Biochemistry and Cell Biology Institute of Biochemistry and Cell BiologyNational Research Council(IBBC/CNR)MonterotondoRomeItaly Plaisant S.R.L. RomeItaly

Is it better to be safe than sorry?This Hamletic dilemma has always stimulated medical-scientific debates in numerous fields of biomedicine.And among these,the preventive-therapeutic approach to the treatment of brain trauma is one of the most striking examples.Traumatic brain injury(TBI)is a leading cause of brain damage among young and elderly populations with a very high hospitalization and death rate.TBI is characterized by two pathologically distinct but strictly consequential phases:a first characterized by an immediate and highly variable mechanical dysfunction of the brain tissue,which involves widespread cell death and tissue degeneration,followed by a second phase which can last from days to even years depending on the severity of the TBI and the patient’s pre-existing health status.Secondary processes,including inflammatory phenomena,oxidative stress associated with metabolic,vascular,and neuro-modulatory deficits,are very often responsible for neuro-motor and psychological deficits leading to long-term disabilities(Kaur and Sharma,2018).

关键词： injury striking modulator

CBE Clima Tool:A free and open-source web application for climate analysis tailored to sustainable building design

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Building Simulation 2024年第3期17卷 493-508页

作者： Giovanni Betti Federico Tartarini Christine Nguyen stefano Schiavon Center for the Built Environment University of California BerkeleyBerkeleyUSA Berkeley Education Alliance for Research in Singapore SingaporeSingapore Heat and Health Research Incubator Faculty of Medicine and HealthThe University of SydneyCamperdownAustralia College of Letters and Sciences University of California BerkeleyBerkeleyUSA

Climate-responsive building design holds immense potential for enhancing comfort,energy efficiency,and environmental sustainability.However,many social,cultural,and economic obstacles might prevent the wide adoption of designing climate-adapted buildings.One of these obstacles can be removed by enabling practitioners to easily access,visualize and analyze local climate data.The CBE Clima Tool(Clima)is a free and open-source web application that offers easy access to publicly available weather files and has been created for building energy simulation and design.It provides a series of interactive visualizations of the variables contained in the EnergyPlus Weather Files and several derived ones like the UTCI or the adaptive comfort indices.It is aimed at students,educators,and practitioners in the architecture and engineering fields.Since its inception,Clima’s user base has exhibited robust growth,attracting over 25,000 unique users annually from across 70 countries.Our tool is poised to revolutionize climate-adaptive building design,transcending geographical boundaries and fostering innovation in the architecture and engineering fields.

关键词： architectural design climate analysis sustainable building design web application building energy simulation open-source software

Integrated CO_(2)capture and reduction catalysis:Role ofγ-Al_(2)O_(3)support,unique state of potassium and synergy with copper

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Journal of Environmental Sciences 2024年第6期140卷 113-122页

作者： Donato Pinto stefano Minorello Zhouping Zhou Atsushi Urakawa Catalysis Engineering Department of Chemical EngineeringDelft University of TechnologyDelft2629HZNetherlands

Carbon dioxide capture and reduction(CCR)process emerges as an efficient catalytic strategy for CO_(2)capture and conversion to valuable chemicals.K-promoted Cu/Al_(2)O_(3)catalysts exhibited promising CO_(2)capture efficiency and highly selective conversion to syngas(CO+H_(2)).The dynamic nature of the Cu-K system at reaction conditions complicates the identification of the catalytically active phase and surface sites.The present work aims at more precise understanding of the roles of the potassium and copper and the contribution of the metal oxide support.Whileγ-Al_(2)O_(3)guarantees high dispersion and destabilisation of the potassium phase,potassium and copper act synergistically to remove CO_(2)from diluted streams and promote fast regeneration of the active phase for CO_(2)capture releasing CO while passing H_(2).A temperature of 350℃is found necessary to activate H_(2)dissociation and generate the active sites for CO_(2)capture.The effects of synthesis parameters on the CCR activity are also described by combination of ex-situ characterisation of the materials and catalytic testing.

关键词： Carbon dioxide Carbon capture and utilisation CO_(2)capture and reduction Solid CO_(2)sorbents Heterogeneous catalysis Potassium Copper catalysts Aluminium oxide

Estimating wood quality attributes from dense airborne LiDAR point clouds

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Forest Ecosystems 2024年第2期11卷 226-235页

作者： Nicolas Cattaneo stefano Puliti Carolin Fischer Rasmus Astrup Norwegian Institute of Bioeconomy Research(NIBIO) Division of Forest and Forest ResourcesHøgskoleveien 81433ÅsNorway

Mapping individual tree quality parameters from high-density LiDAR point clouds is an important step towards improved forest inventories.We present a novel machine learning-based workflow that uses individual tree point clouds from drone laser scanning to predict wood quality indicators in standing trees.Unlike object reconstruction methods,our approach is based on simple metrics computed on vertical slices that summarize information on point distances,angles,and geometric attributes of the space between and around the points.Our models use these slice metrics as predictors and achieve high accuracy for predicting the diameter of the largest branch per log (DLBs) and stem diameter at different heights (DS) from survey-grade drone laser scans.We show that our models are also robust and accurate when tested on suboptimal versions of the data generated by reductions in the number of points or emulations of suboptimal single-tree segmentation scenarios.Our approach provides a simple,clear,and scalable solution that can be adapted to different situations both for research and more operational mapping.

关键词： UAV laser scanning Wood quality Machine learning Point cloud metrics

A quantitative analysis of the US materials flow methodology and comparison to the EU methodology for MSW statistics

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Waste Disposal and Sustainable Energy 2024年第1期6卷 85-94页

作者： Demetra Tsiamis Fabio Poretti stefano Consonni Marco J.Castaldi Earth Engineering Center Department of Chemical EngineeringThe City College of New YorkNew YorkNYUSA Dipartimento Di Energetica Politecnico Di MilanoPiazza Leonardo da Vinci 3220133MilanItaly

The European Union(EU)and the United States(US)determine municipal solid waste(MSW)statistics differently.The EU applies a site-specific methodology that directly measures waste whereas the US employs a materials flow methodology that estimates MSW statistics indirectly based on production and recovery data from industries.This study dissects the materials flow methodology and presents quantitative materials flow Sankey diagrams for the primary MSW materials to highlight data gaps that can be addressed to improve the methodology’s accuracy.Private industry plastics data were applied to the materials flow methodology,and the results were within 10%of the plastics statistics reported by the US Environmental Protection Agency(US EPA).Drawbacks to the methodologies include EU measurement inaccuracies due to double-counting and not accounting for residual waste in the US.The latter may partially explain why landfilling tonnages reported by the US EPA were approximately 60%less than the tonnages reported by the Waste to Energy Research and Technology Council(WTERT)in its national MSW survey that applied the EU methodology in the US.Unlike the EU,there is no US national policy that requires states to measure and report state-level waste data to the US EPA.Future improvements in US MSW statistics rely heavily on the implementation of national policies to homogenize the measurement and collection of waste data from states.

关键词： Materials flow methodology Site-specific methodology United States European Union Municipal solid waste Discrepancy

Endoscopic treatment of scarred polyps with a non-thermal device(Endorotor):A review of the literature

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World Journal of Gastroenterology 2024年第12期30卷 1706-1713页

作者： Mariam Zaghloul Hameed Rehman stefano Sansone Konstantinos Argyriou Adolfo Parra-Blanco Department of Hepatology Gastroenterology and Infectious DiseasesKafrelsheikh UniversitKafr-Elshikh 33516Egypt Department of Gastroenterology Service Nottingham City Hospital CampusNottingham University Hospitals NHS TrustNottingham NG51PBUnited Kingdom Department of Gastroenterology University Hospital of LarissaLarissa 41334Greece NIHR Nottingham Biomedical Research Centre Nottingham University Hospitals NHS Trust and University of NottinghamNottingham NG72UHUnited Kingdom

Endoscopic resection(ER)of colorectal polyps has become a daily practice in most endoscopic units providing a colorectal cancer screening program and requires the availability of local experts and high-end endoscopic devices.ER procedures have evolved over the past few years from endoscopic mucosal resection(EMR)to more advanced techniques,such as endoscopic submucosal dissection and endo-scopic full-thickness resection.Complete resection and disease eradication are the ultimate goals of ER-based techniques,and novel devices have been developed to achieve these goals.The EndoRotor®Endoscopic Powered Resection System(Interscope Medical,Inc.,Northbridge,Massachusetts,United States)is one such device.The EndoRotor is a powered resection tool for the removal of alimentary tract mucosa,including post-EMR persistent lesions with scarring,and has both CE Mark and FDA clearance.This review covers available published evidence documenting the usefulness of EndoRotor for the management of recurrent colorectal polyps.

关键词： EndoRotor Scarred polyps Recurrent polyps Colorectal cancer Colorectal polyps

A CFD Model to Evaluate Near-Surface Oil Spill from a Broken Loading Pipe in Shallow Coastal Waters

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Fluid Dynamics & Materials Processing 2024年第1期20卷 59-77页

作者： Portia Felix Lee Leon Derek Gay stefano Salon Hazi Azamathulla Department of Civil and Environmental Engineering The University of the West IndiesSt.AugustineTrinidad and Tobago National Institute of Oceanography and Experimental Geophysics-OGS TriesteItaly

Oil spills continue to generate various issues and concerns regarding their effect and behavior in the marine environment,owing to the related potential for detrimental environmental,economic and social implications.It is essential to have a solid understanding of the ways in which oil interacts with the water and the coastal ecosystems that are located nearby.This study proposes a simplified model for predicting the plume-like transport behavior of heavy Bunker C fuel oil discharging downward from an acutely-angled broken pipeline located on the water surface.The results show that the spill overall profile is articulated in three major flow areas.The first,is the source field,i.e.,a region near the origin of the initial jet,followed by the intermediate or transport field,namely,the region where the jet oil flow transitions into an underwater oil plume flow and starts to move horizontally,and finally,the far-field,where the oil re-surface and spreads onto the shore at a significant distance from the spill site.The behavior of the oil in the intermediate field is investigated using a simplified injection-type oil spill model capable of mimicking the undersea trapping and lateral migration of an oil plume originating from a negatively buoyant jet spill.A rectangular domain with proper boundary conditions is used to implement the model.The Projection approach is used to discretize a modified version of the Navier-Stokes equations in two dimensions.A benchmark fluid flow issue is used to verify the model and the results indicate a reasonable relationship between specific gravity and depth as well as agreement with the aerial data and a vertical temperature profile plot.

关键词： CFD model Navier-Stokes equations projection method water surface oil spill shallow coastal waters