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Modelling Strategy and Parametric Study of Metal Gaskets for Automotive Applications

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Computer Modeling in Engineering & Sciences 2020年第10期125卷 51-64页

作者： Fabio Bruzzone Cristiana Delprete carlo Rosso Politecnico di Torino Corso Duca degli Abruzzi 24Torino10129Italy

This paper is focused on finite element simulation of cylinder head *** element codes support several methodologies,each of which has its own strengths and *** of the key points lies in the influence of the gasket geometry on its final *** a contribution can come from the detailed modelling of the gasket or by defining a global non-linear behaviour in which material and geometry non-linearities are *** approaches were used to simulate the gasket *** first one consists in using a 2D approach,which allows to model through-thickness non-linear behaviour of *** second one consists in using conventional 3D finite element *** numerical methods have been discussed and compared in relation to the accordance with experimental data,amount of information supplied and computational time ***,a parametric study shows how some geometric parameters influence the compressive load and the elastic recovery of a single-layer steel gasket.

关键词： Gaskets finite elements parametric study

Why did life develop on the surface of the Earth in the Cambrian？

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Geoscience Frontiers 2016年第6期7卷 865-873页

作者： carlo Doglioni Johannes Pignatti Max Coleman Department of Earth Sciences Sapienza University 00185 Rome Italy NASA Jet Propulsion Laboratory California Institute of Technology Pasadena CA 91109 USA NASA Astrobiology Institute USA

Life was limited for most of Earth＇s history, remaining at a primitive stage and mostly marine until about 0.55 Ga. In the Paleozoic, life eventually exploded and colonized the continental realm. Why had there been such a long period of delayed evolution of life？ Early life was dominated by Archaea and Bacteria, which can survive ionizing radiation better than other organisms. The magnetic field preserves the atmosphere, which is the main shield of UV radiation. We explore the hypothesis that the Cambrian explosion of life could have been enabled by the increase of the magnetic field dipole intensity due to the solidification of the inner core, caused by the cooling of the Earth, and the concomitant decrease with time of the high-energy solar flux since the birth of the solar system. Therefore, the two phenomena could be responsible for the growth and thickening of the atmosphere and the development of land surface life.

关键词： Origin of lifeInner core solidificationSolar ionizing radiations

The promise of neuroprotection by dietary restriction in glaucoma

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Neural Regeneration Research 2022年第1期17卷 45-47页

作者： Rossella Russo carlo Nucci Annagrazia Adornetto Preclinical and Translational Pharmacology Department of PharmacyHealth and Nutritional SciencesUniversity of CalabriaRendeItaly Ophthalmology Unit Department of Experimental MedicineUniversity of Rome Tor VergataRomeItaly

Glaucoma,a progressive age-related optic neuropathy characterized by the death of retinal ganglion cells,is the most common neurodegenerative cause of irreversible blindness *** therapeutic management of glaucoma,which is limited to lowering intraocular pressure,is still a challenge since visual loss progresses in a significant percentage of treated *** dietary regimens have received considerable attention as adjuvant strategy for attenuating or delaying the progression of neurodegenerative *** we discuss the literature exploring the effects of modified eating patterns on retinal aging and resistance to stressor stimuli.

关键词： aging caloric restriction fasting glaucoma neurodegeneration retina retinal ganglion cells

Control of systems with sector-bounded nonlinearities： robust stability and command effort minimization by disturbance rejection

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Control Theory and Technology 2016年第3期14卷 209-223页

作者： carlo NOVARA Enrico CANUTO Donato CARLUCCI Politecnico di Torino Italy

The paper shows that a control strategy with disturbance rejection is able to reduce the control effort to a minimum, ensuring at the same time a desired performance level. The disturbance to be rejected is completely unknown, except for a sectorial bound. The control unit is endowed with an extended state observer which includes a disturbance dynamics, whose state tracks the unknown disturbance to be rejected. In summary, the novel contributions of the paper are the following. First, we derive a robust stability condition for the proposed control scheme, holding for all the nonlinearities that are bounded by a known （or estimated） maximum slope. Second, we propose a novel approach for designing the observer and state feedback gains, which guarantee robust closed-loop stability. Third, we show that the designed control system yields, with a minimum control effort, the same control performance as a robust state feedback control, which on the contrary may require a larger command activity. Two simulated case studies are presented to show the effectiveness of the proposed approach.

关键词： Disturbance rejection extended observer robust stability sector-bounded nonlinear systems

Embedded model control:Reconciling modern control theory and error-based control design

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Control Theory and Technology 2018年第4期16卷 261-283页

作者： Enrico CANUTO carlo NOVARA Luigi COLANGELO Politecnico di Torino Italy

The paper addresses the problem of reconciling the modern control paradigm developed by R. Kalman in the sixties of the past century, and the centenary error-based design of the proportional, integrative and derivative （PID） controllers. This is done with the help of the error loop whose stability is proved to be necessary and sufficient for the close-loop plant stability. The error loop is built by cascading the uncertain plant-to-model discrepancies （causal, parametric, initial state, neglected dynamics）, which are driven by the design model output and by arbitrary bounded signals, with the control unit transfer functions. The embedded model control takes advantage of the error loop and its equations to design appropriate algorithms of the modern control theory （state predictor, control law, reference generator）, which guarantee the error loop stability and performance. A simulated multivariate case study shows modeling and control design steps and the coherence of the predicted and simulated performance.

关键词： Modern control theory error-based design embedded model control error loop disturbance rejection

Asthma and gastroesophageal reflux disease: Effect of long-term pantoprazole therapy

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World Journal of Gastroenterology 2005年第48期11卷 7657-7660页

作者： Calabrese carlo Fabbri Anna Areni Alessandra Scialpi carlo Zahlane Desiree Di Febo Giulio Department of Internal Medicine and Gastroenterology

AIM： To define the prevalence of gastroesophageal reflux disease （GERD） in mild persistent asthma and to value the effect of pantoprazole therapy on asthmatic ***： Seven of thirty-four asthmatic patients without GERD served as the non-GERD control group. Twenty-seven of thirty-four asthmatic patients had GERD （7/27 also had erosive esophagitis, sixteen of them presented GERD symptoms. An upper gastrointestinal endoscopy was performed in all the subjects to obtain five biopsy specimens from the lower 5 cm of the esophagus. Patients were considered to have GERD when they had a dilation of intercellular space （DIS）〉0.74 μm at transmission electron microscopy. Patients with GERD were treated with pantoprazole, 80 mg/day. Forced expiratory volume in one second （FEV1） was performed at entry and after 6 mo of treatment. Asthmatic symptoms were recorded. The required frequency of inhaling rapid acting β2-agonists was self-recorded in the patients＇ ***： Seven symptomatic patients presented erosive esophagitis. Among the 18 asymptomatic patients, 11 presented DIS, while all symptomatic patients showed ultrastructural esophageal damage. Seven asymptomatic patients did not present DIS. At entry the mean of FEV1 was 1.91 L in symptomatic GERD patients and 1.88 L in asymptomatic GERD patients. After the treatment, 25 patients had a complete recovery of DIS and reflux symptoms. Twenty-three patients presented a regression of asthmatic symptoms with normalization of FEV1. Four patients reported a significant improvement of symptoms and their FEV1 was over 80%.CONCLUSION： GERD is a highly prevalent condition in asthma patients. Treatment with pantoprazole （80 mg/day） determines their improvement and complete regression.

关键词： Asthma Gastroesophageal reflux disease Pantoprazole NERD ERD Dilated intercellular spaces TEN

Photometric study and preliminary elements of the low-mass ratio W UMa system ASAS 021209+2708.3

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Research in Astronomy and Astrophysics 2011年第7期11卷 843-850页

作者： Francesco Acerbi carlo Barani Massimiliano Martignoni Via Zoncada 51 26845 Codogno(LO)Italy Via Molinetto 35 26845 Triulza di Codogno(LO)Italy Via Don G.Minzoni 26/D 20020 Magnago(MI)Italy

We present CCD B and V light curves,obtained in the year 2006,and a photometric solution of the low-mass ratio contact binary ASAS 021209＋2708.3. With our data we were able to determine six new times of minimum light and refine the orbital period of the system to 0.3181963 *** light curves are analyzed using the 2003 version of the Wilson-Devinney program and the analysis was performed with and without adding a spot on the surface of one star because the light curves appear to exhibit a typical O’Connell effect,with Maximum I brighter than Maximum *** results show that ASAS 021209＋2708.3 may be classified as an A-subtype W Ursae Majoris system with a small mass ratio q=0.1889,a large over-contact degree of f= 0.587,a very small difference between the component temperatures of Δ T=53 K and an orbital inclination of i=81°.It is known that deep（f50%） ,low-mass ratio（q0.25） overcontact binary stars are a very important resource for understanding the phenomena of Blue Straggler/FK Com-type *** formations of Blue Straggler stars and FK Com-type stars are unsolved problems in stellar *** of the possible explanations for their formation is from the coalescence of W UMa-type overcontact binary *** absolute dimensions of ASAS 021209＋2708.3 are estimated and its dynamical evolution is inferred.

关键词： binaries:eclipsing–stars:fundamental parameters–stars:individual:ASAS 021209+2708.3

The role of MicroRNAs in human cancer

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Signal Transduction and Targeted Therapy 2016年第1期1卷 149-157页

作者： Yong Peng carlo M Croce Department of Thoracic Surgery State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengduChina Collaborative Innovation Center of Biotherapy ChengduChina Department of Molecular Virology Immunology and Medical GeneticsComprehensive Cancer CenterThe Ohio State UniversityColumbusOHUSA

MicroRNAs(miRNAs)are endogenous,small non-coding RNAs that function in regulation of gene *** evidences have demonstrated that miRNA expression is dysregulated in human cancer through various mechanisms,including amplification or deletion of miRNA genes,abnormal transcriptional control of miRNAs,dysregulated epigenetic changes and defects in the miRNA biogenesis *** may function as either oncogenes or tumor suppressors under certain *** dysregulated miRNAs have been shown to affect the hallmarks of cancer,including sustaining proliferative signaling,evading growth suppressors,resisting cell death,activating invasion and metastasis,and inducing *** increasing number of studies have identified miRNAs as potential biomarkers for human cancer diagnosis,prognosis and therapeutic targets or tools,which needs further investigation and *** this review,we focus on how miRNAs regulate the development of human tumors by acting as tumor suppressors or oncogenes.

关键词： expression. cancer invasion

A Complex Systems Science Perspective on Wireless Networks

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Journal of Systems Science & Complexity 2016年第4期29卷 1034-1056页

作者： MACALUSO Irene GALIOTTO carlo MARCHETTI Nicola DOYLE Linda CTVR Telecommunications Research Center Trinity College Dublin

The paper targets a future world where all wireless networks are self-organising entities and in which the predominant mode of spectrum access is dynamic. The paper explores whether the behaviour of a collection of autonomous self-organising wireless systems can be treated as a complex system and whether complex systems science can shed light on the design and deployment of these networks. The authors focus on networks that self-organise from a frequency perspective to understand the behaviour of a collection of wireless self-organising nodes. Each autonomous network is modelled as a cell in a lattice and follows a simple set of self-organisation rules. Two scenarios are considered, one in which each cell is based on cellular automata and which provides an abstracted view of interference and a second in which each cell uses a self-organising technique which more accurately accounts for interference. The authors use excess entropy to measure complexity and in combination with entropy gain an understanding of the structure emerging in the lattice for the self-organising networks. The authors show that the self-organising systems presented here do exhibit complex behaviour. Finally,the authors look at the robustness of these complex systems and show that they are robust against changes in the environment.

关键词： Dynamic spectrum access excess entropy robustness self organising wireless networks.