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INFLUENCE OF TIBETAN PLATEAU ON LOW LEVEL JET IN EAST ASIA

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Science China Chemistry 1985年第1期28卷 68-81页

作者：孙淑清,lorenzo DELL'OSSO Institute of Atmospheric Physics Academia Sinica Beijing European Centre for Medium Range Weather Forecasts Reading England

In this paper, the essential role played by tie Tibetan Plateau in the formation of large scale low level jet over China is shown. Using the ECMWF limited area model we have performed some numerical experiments with various modified orography for a real case. The comparison of no-mountain run with the control one shows that the Plateau acts as a west boundary to the flows from the south, thus helping concentrate the momentum in a narrow belt. The close connection between the jet and the monsoon current is also investigated. The confluence of the currents from the subtropical high and mid-latitude trough mainly results in the strong wind centre at mid-troposphere rather than at lower level.

关键词： EAST JET high than

Empowering digital twins with eXtended reality collaborations

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Virtual Reality & Intelligent Hardware 2022年第6期4卷 487-505页

作者： lorenzo STACCHIO Alessia ANGELI Gustavo MARFIA Department for Life Quality Studies University of BolognaItaly Department of Computer Science and Engineering University of BolognaItaly Department of the Arts University of BolognaItaly

Background The advancements of Artificial Intelligence,Big Data Analytics,and the Internet of Things paved the path to the emergence and use of Digital Twins(DTs)as technologies to“twin”the life of a physical entity in different fields,ranging from industry to *** the same time,the advent of eXtended Reality(XR)in industrial and consumer electronics has provided novel paradigms that may be put to good use to visualize and interact with *** technologies can support human-to-human interactions for training and remote assistance and could transform DTs into collaborative intelligence *** We here present the Human Collaborative Intelligence empowered Digital Twin framework(HCLINT-DT)integrating human annotations(e.g.,textual and vocal)to allow the creation of an all-in-one-place resource to preserve such *** framework could be adopted in many fields,supporting users to learn how to carry out an unknown process or explore others’past *** The assessment of such a framework has involved implementing a DT supporting human annotations,reflected in both the physical world(Augmented Reality)and the virtual one(Virtual Reality).Con-clusions The outcomes of the interface design assessment confirm the interest in developing HCLINT-DT-based ***,we evaluated how the proposed framework could be translated into a manufacturing context.

关键词： Digital twin eXtended reality Human collaborative intelligence

Implicit-Explicit Runge-Kutta Schemes for the Boltzmann-Poisson System for Semiconductors

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Communications in Computational Physics 2014年第5期15卷 1291-1319页

作者： Giacomo Dimarco lorenzo Pareschi Vittorio Rispoli Universite de Toulouse UPSINSAUT1UTMCNRSUMR 5219Institut de Mathematiques de ToulouseF-31062 ToulouseFrance Department of Mathematics and Computer Science University of Ferraravia Machiavelli 3544121 FerraraItaly.

In this paper we develop a class of Implicit-Explicit Runge-Kutta schemes for solving the multi-scale semiconductor Boltzmann *** relevant scale which characterizes this kind of problems is the diffusive *** means that,in the limit of zero mean free path,the system is governed by a drift-diffusion *** aim is to develop a method which accurately works for the different regimes encountered in general semiconductor simulations:the kinetic,the intermediate and the diffusive ***,we want to overcome the restrictive time step conditions of standard time integration techniques when applied to the solution of this kind of phenomena without any deterioration in the *** a result,we obtain high order time and space discretization schemes which do not suffer from the usual parabolic stiffness in the diffusive *** show different numerical results which permit to appreciate the performances of the proposed schemes.

关键词： IMEX-RK methods asymptotic preserving methods semiconductor Boltzmann equation drift-diffusion limit

Direct carotid puncture in acute ischaemic stroke intervention

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Stroke & Vascular Neurology 2020年第1期5卷 71-79页

作者： Elisa Colombo lorenzo Rinaldo Giuseppe Lanzino Neurologic Surgery Mayo ClinicRochesterMinnesotaUSA

Endovascular intervention for acute ischaemic stroke care is mostly performed in older patients,often with unfavourable aortic and supra-aortic anatomy,as well as cardiovascular comorbidities.A significant subset of them may benefit from transcervical access as the initial approach for mechanical *** fact,direct carotid artery puncture in these cases has the advantage to bypass the anatomical obstacles and achieve faster *** is advised when common carotid artery access is pursued in order to avoid adverse events,including haematoma formation,iatrogenic arterial dissection and sheath *** spite of potential complications,direct carotid puncture in acute ischaemic stroke intervention overcomes challenging angioarchitecture and may reduce the rate of poor clinical outcomes associated with delayed revascularisation in certain cases.

关键词： carotid puncture anatomy

On the scale-up criteria for bubble columns

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Petroleum 2019年第2期5卷 114-122页

作者： Giorgio Besagni lorenzo Gallazzini Fabio Inzoli Department of Energy Politecnico di MilanoVia Lambruschini 4a20156MilanoItaly

It is generally admitted that experimental data obtained in“laboratory-scale”bubble columns are representative of“industrial-scale”reactors if the well-known three“Wilkinson et ***-up criteria”are satisfied:(a)the diameter of the bubble column is larger than 0.15 m,(b)the sparger openings are larger than 1e2mm and(c)the aspect ratio is larger than *** aim of this communication is to contribute to the existing *** this end,this communication collects relevant experimental investigation and include new experimental data:in particular,we have experimentally studied the combined effect of the aspect ratio(within the range of 1e15)and the sparger design(considering both“coarse”and“fine”spargers)on the gas holdup in a large-diameter and large-scale gas-liquid bubble *** bubble column has been operated both in the batch mode and in the counter-current *** air has been used as the gaseous phase in all the experiments,while the liquid phase has included deionized water and different aqueous solutions of organic(i.e.,ethanol)and inorganic(i.e.,sodium chloride,NaCl)active *** is found that the“Wilkinson et ***-up criteria”are valid for the air-water case in the batch mode for“very-coarse”***,they are no more valid when considering different liquid velocity,and/or aqueous solutions of active agents,and other sparger openings.

关键词： Bubble column Scale-up Gas sparger Gas holdup Liquid phase properties

Near-bankfull floods in an Alpine stream:Effects on the sediment mobility and bedload magnitude

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International Journal of Sediment Research 2018年第1期33卷 27-34页

作者： Riccardo Rainato Luca Mao lorenzo Picco Department of Land Environment Agriculture and Forestry University of Padova Department of Ecosystems and Environment Pontificia Universidad Catòlica de Chile

In a mountain environment, the transport of coarse material is a key factor for many fields such as geomorphology, ecology, hazard assessment, and reservoir management. Despite this, there have been only a few field investigations of bedload, in particular using multiple monitoring methods. In this sense,attention has frequently focused on the effects of "high magnitude/low frequency floods" rather than on "ordinary events". This study aims to analyze the sediment dynamics triggered by three high-frequency floods(recurrence interval "RI" between 1.1 and 1.7 yr) that occurred in the Rio Cordon basin during 2014. The flood events were investigated in terms of both sediment mobility and bedload magnitude. The Rio Cordon is an Alpine basin located in northeastern Italy. The catchment has a surface area of 5 km~2,ranging between 1763 and 2763 m above sea level. The Rio Cordon flows on an armored streambed layer,with a stable step-pool configuration and large boulders. Since 1986, the basin has been equipped with a permanent station to continuously monitor water discharge and sediment flux. To investigate sediment mobility, 250 PIT-tags were installed in the streambed in 2012. The 2014 floods showed a clear difference in terms of tracer displacement. The near-bankfull events showed equal mobility conditions, with mean travel distance one order of magnitude higher than the below-bankfull event. Furthermore, only the near-bankfull events transported coarse material to the monitoring station. Both events had a peak discharge up to 2.06 m~3 s, but the bedload transport rates differed by more than one order of magnitude, proving that under the current supply-limited condition, the bedload appears more related to the sediment supply than to the magnitude of the hydrological features. In this sense, the results demonstrated that near-bankfull events can mobilize large amounts of material for long distances, and that floods of apparently similar magnitude may lead to different se

关键词： Bedload Alpine basin Sediment dynamics Bedload tracing PIT-tags

Steel Design by Advanced Analysis: Material Modeling and Strain Limits

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Engineering 2019年第2期5卷 243-249页

作者： Leroy Gardner Xiang Yun Andreas Fieber lorenzo Macorini Department of Civil and Environmental Engineering Imperial College London London SW7 2AZ UK

Structural analysis of steel frames is typically performed using beam elements. Since these elements are unable to explicitly capture the local buckling behavior of steel cross-sections, traditional steel design specifications use the concept of cross-section classification to determine the extent to which the strength and deformation capacity of a cross-section are affected by local buckling. The use of plastic design methods are restricted to Class 1 cross-sections, which possess sufficient rotation capacity for plastic hinges to develop and a collapse mechanism to form. Local buckling prevents the development of plastic hinges with such rotation capacity for cross-sections of higher classes and, unless computationally demanding shell elements are used, elastic analysis is required. However, this article demonstrates that local buckling can be mimicked effectively in beam elements by incorporating the continuous strength method (CSM) strain limits into the analysis. Furthermore, by performing an advanced analysis that accounts for both geometric and material nonlinearities, no additional design checks are required. The positive influence of the strain hardening observed in stocky cross-sections can also be harnessed, provided a suitably accurate stress–strain relationship is adopted;a quad-linear material model for hot-rolled steels is described for this purpose. The CSM strain limits allow cross-sections of all slenderness to be analyzed in a consistent advanced analysis framework and to benefit from the appropriate level of load redistribution. The proposed approach is applied herein to individual members, continuous beams, and frames, and is shown to bring significant benefits in terms of accuracy and consistency over current steel design specifications.

关键词： Advanced analysis Continuous strength method Local buckling Material modeling Strain limits

GIS tools for preliminary debris-flow assessment at regional scale

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Journal of Mountain Science 2017年第12期14卷 2498-2510页

作者： cavalli marco crema stefano trevisani sebastiano marchi lorenzo consiglio nazionale delle ricerche istituto di ricerca per la protezione idrogeologicaCorso Stati Uniti 435127 PadovaItaly universitàdi padova dipartimento territorio e sistemi agro-forestaliVia dell’Universita 1635020 Legnaro(PD)Italy universitàiuav di venezia dipartimento di architettura costruzione conservazioneDorsoduro 220630123 VeneziaItaly

The assessment of the areas endangered by debris flows is a major issue in the context of mountain watershed management. Depending on the scale of analysis, different methods are required for the assessment of the areas exposed to debris *** 2-D numerical models are advised for detailed mapping of inundation areas on individual alluvial fans, preliminary recognition of hazard areas at the regional scale can be adequately performed by less data-demanding methods, which enable priority ranking of channels and alluvial fans at risk by debris flows. This contribution focuses on a simple and fast procedure that has been implemented for regionalscale identification of debris-flow prone channels and prioritization of the related alluvial fans. The methodology is based on the analysis of morphometric parameters derived from Digital Elevation Models(DEMs). Potential initiation sites of debris flows are identified as the DEM cells that exceed a threshold of slope-dependent contributing area. Channel reaches corresponding to debris flows propagation, deceleration and stopping conditions are derived from thresholds of local slope. An analysis of longitudinal profiles is used for the computation of the runout distance of debris flows. Information on erosion-resistant bedrock channels and sediment availability surveyed in the field are taken into account in the applications. A set of software tools was developed and made available(https://***/Hydrogeomorphology Tools) to facilitate the application of the procedure. This approach, which has been extensively validated by means of field checks, has been extensively applied in the eastern Italian Alps. This contribution discusses potential and limitations of the method in the frame of the management of small mountain watersheds.

关键词： Debris flow Geographic information system Digital elevation models Runout Alluvial fan Watershed management Geomorphometry

New obesity classification criteria as a tool for bariatricsurgery indication

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World Journal of Gastroenterology 2016年第2期22卷 681-703页

作者： Antonino De lorenzo Laura Soldati Francesca Sarlo Menotti Calvani Nicola Di lorenzo Laura Di Renzo Division of Clinical Nutrition and Nutrigenomic Department of Biomedicine and PreventionUniversity of Tor Vergata00133 RomeItaly Department of Internal Medicine UOSD Service of Clinical Nutritionparenteral therapy and anorexia nervosaPoliclinico Tor Vergata00133 RomeItaly Department of Health Sciences University of Milan20122 MilanItaly Department of Agriculture University of Naples“Federico II” 80055 Portici(NA)Italy Department of Surgical Sciences University of Tor VergataPoliclinico Tor Vergata00133 RomeItaly

Obesity plays relevant pathophysiological role in the development of health problems, arising as result of complex interaction of genetic, nutritional, and metabolic factors. Due to the role of adipose tissue in lipid and glucose metabolism, and low grade inflammation, it is necessary to classify obesity on the basis of body fat composition and distribution, rather than the simply increase of body weight, and the Body Mass Index. The new term of adiposopathy(‘‘sick fat'') clearly defines the pathogenic role of adipose tissue. Four phenotypes of obese individuals have been described:(1) normal weight obese(NWO);(2) metabolically obese normal weight;(3) metabolically healthy obese; and(4) metabolically unhealthy obese or "at risk" obese. Moreover, sarcopenic obesity has been related to all the phenotypes. The category of normal weight lean, represented by metabolically healthy normal weight has been classified to distinguish from NWO. It is crucial to recommend a bariatric surgery taking into account adiposopathy and sick fat that occurs with the expansion of fat mass, changing the inflammatory and metabolic profile of the patient. Body fat percentage and genetic polymorphism have to be evaluated to personalize the best bariatric surgery intervention.

关键词： Obesity Adiposopathy Normal weightlean Normal weight obese Metabolically obese normalweight Metabolically healthy obese Metabolicallyhealthy normal weight Metabolically unhealthy obese Laparoscopic gastric banding Fat mass