2,876 research outputs found
Refined shell elements for the analysis of functionally graded structures
The present paper considers the static analysis of plates and shells made of Functionally Graded Material (FGM), subjected to mechanical loads. Refined models based on the Carrera's Unified Formulation (CUF) are employed to account for grading material variation in the thickness direction. The governing equations are derived from the Principle of Virtual Displacement (PVD) in order to apply the Finite Element Method (FEM). A nine-nodes shell element with exact cylindrical geometry is considered. The shell can degenerate in the plate element by imposing an infinite radius of curvature. The Mixed Interpolation of Tensorial Components (MITC) technique is extended to the CUF in order to contrast the membrane and shear locking phenomenon. Different thickness ratios and orders of expansion for the displacement field are analyzed. The FEM results are compared with both benchmark solutions from literature and the results obtained using the Navier method that provides the analytical solution for simply-supported structures subjected to sinusoidal pressure loads. The shell element based on refined theories of the CUF turns out to be very efficient and its use is mandatory with respect to the classical models in the study of FGM structures
Robust Gravitational Wave Burst Detection and Source Localization in a Network of Interferometers Using Cross Wigner Spectra
We discuss a fast cross-Wigner transform based technique for detecting
gravitational wave bursts, and estimating the direction of arrival, using a
network of (three) non co-located interferometric detectors. The performances
of the detector as a function of signal strength and source location, and the
accuracy of the direction of arrival estimation are investigated by numerical
simulations.Comment: accepted in Class. Quantum Gravit
Santi, eroi e lâunitaÌ delle virtuÌ. Una proposta esemplarista di educazione morale
This article sheds light on moral education from an exemplarist perspective. Following Linda Zagzebski's Exemplarist Virtue Theory, we relate several fundamental exemplarist intuitions to the classical virtue ethical debate over the unity-disunity of the virtues, to endorse a pluralistic exemplar-based approach to moral education ("Empe"). After a few preliminary remarks, we argue that Empe amounts to defending "a prima facie" disunitarist perspective in moral theory, which admits both exemplarity in all respects (moral sainthood) and single-domain exemplarity (moral heroism). Then, we evaluate the effectiveness of heroes and saints for moral education, according to four criteria derived from Empe. This analysis allows us to conclude that moral education should value both kinds of exemplars and, therefore, adopt weaker standards of exemplarity than the unitarist's ones
First record of Spermatozopsis similis (Chlorophyta) in a marine environment
El objetivo del presente trabajo es registrar por primera vez la presencia de Spermatozopsis similis H.R.Preisig et M.Melkonian en un ambiente marino y describir su morfologĂa y abundancia en la RĂa del JabalĂ (BahĂa Anegada, Buenos Aires, Argentina). Se realizaron muestreos mensuales entre los meses de junio y noviembre de 2006 y las muestras se observaron bajo microscopio Ăłptico y electrĂłnico de barrido. Los ejemplares de S. similis presentaron cĂ©lulas biflageladas fusiformes y levemente espiraladas, con flagelos de largo desigual. S. similis fue un componente importante del fitoplancton en la RĂa del JabalĂ entre junio y agosto de 2006, alcanzando su mĂĄxima abundancia durante agosto (6770 cĂ©l.ml-1), durante este perĂodo se observaron valores muy altos y fluctuantes en la salinidad. Este trabajo constituye el primer registro de Spermatozopsis similis en un ambiente marino.The objective of the present study is to report for the first time the occurrence of Spermatozopsis similis H. R. Preisig et M. Melkonian in a marine environment, describing the morphology and its abundance in RĂa del JabalĂ; BahĂa Anegada, Buenos Aires, Argentina. Samples were taken monthly between June and November 2006 and were observed under light and scanning electron microscope. Specimens of S. similis showed biflagellate, fusiform and slightly spiraled cells, with flagella of unequal length. S. similis was an important component of phytoplankton in RĂa del JabalĂ between June and August 2006, reaching its maximum abundance in August (6 770 cĂ©l.ml-1), during this period there were observed very high and fluctuating values of salinity. This paper is the first record of S. similis in a marine environment.Fil: Fernandez, Carolina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico BahĂa Blanca. Instituto Argentino de OceanografĂa (i); ArgentinaFil: Gauna, Maria Cecilia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico BahĂa Blanca. Instituto Argentino de OceanografĂa (i); ArgentinaFil: Croce, Maria Emilia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico BahĂa Blanca. Planta Piloto de IngenierĂa QuĂmica (i); Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico BahĂa Blanca. Instituto Argentino de OceanografĂa (i); ArgentinaFil: Parodi, Elisa Rosalia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico BahĂa Blanca. Instituto Argentino de OceanografĂa (i); Argentina. Universidad Nacional del Sur. Departamento de BiologĂa, BioquĂmica y Farmacia. Laboratorio de EcologĂa AcuĂĄtica; Argentin
EVALITA 2020: Overview of the 7th Evaluation Campaign of Natural Language Processing and Sspeech Tools for Italian
Lessons Learned from EVALITA 2020 and Thirteen Years of Evaluation of Italian Language Technology
This paper provides a summary of the 7th Evaluation Campaign of Natural Language Processing and Speech Tools for Italian (EVALITA2020) which was held online on December 17th, due to the 2020 COVID-19 pandemic. The 2020 edition of Evalita included 14 different tasks belonging to five research areas, namely: (i) Affect, Hate, and Stance, (ii) Creativity and Style, (iii) New Challenges in Long-standing Tasks, (iv) Semantics and Multimodality, (v) Time and Diachrony. This paper provides a description of the tasks and the key findings from the analysis of participant outcomes. Moreover, it provides a detailed analysis of the participants and task organizers which demonstrates the growing interest with respect to this campaign. Finally, a detailed analysis of the evaluation of tasks across the past seven editions is provided; this allows to assess how the research carried out by the Italian community dealing with Computational Linguistics has evolved in terms of popular tasks and paradigms during the last 13 years
Intensifying Air Separation Units
This research activity shows the possibility to further intensify air separation units (ASUs). Several modifications to the traditional process layout are proposed and simulated by means of well-established simulation suites. The proposed modifications deal with the upgrading of oxygen purity, the recycle of rich argon stream, and the possibility to generate energy. The novel process solutions are compared with the traditional process and techno-economic assessment is provided. The payback time on the revamping investment is estimated in the order of 5 years for Terniâs ASU, owned by Linde Gas Italia S.r.l., which has been selected as test-case
Effect of oxide nanoparticles on thermal and mechanical properties of electrospun separators for lithium-ion batteries
This study reports the fabrication and characterization of poly(ethylene oxide) (PEO) and poly(vinylidenefluoride-co-chlorotrifluoroethylene) (PVDF-CTFE) nanofibrous separators for lithium-ion batteries loaded with different amounts of fumed-silica and tin oxide nanoparticles. Membrane morphological characterization (SEM, TEM) showed the presence of good-quality nanofibres containing nanoparticles. Thermal degradation and membrane mechanical properties were also investigated, and a remarkable effect of nanoparticle addition on membrane mechanical properties was found. In particular, PEO membranes were strengthened by the addition of metal oxide, whereas PVDF-CTFE membranes acquired ductility
A Canine Gait Analysis Protocol for Back Movement Assessment in German Shepherd Dogs
Objective-To design and test a motion analysis protocol for the gait analysis of adult German Shepherd (GS) dogs with a focus in the analyses of their back movements. Animals-Eight clinically healthy adult large-sized GS dogs (age, 4 +/- 1.3 years; weight, 38.8 +/- 4.2 kg). Procedures-A six-camera stereo-photogrammetric system and two force platforms were used for data acquisition. Experimental acquisition sessions consisted of static and gait trials. During gait trials, each dog walked along a 6 m long walkway at self-selected speed and a total of six gait cycles were recorded. Results-Grand mean and standard deviation of ground reaction forces of fore and hind limbs are reported. Spatial-temporal parameters averaged over gait cycles and subjects, their mean, standard deviation and coefficient of variance are analyzed. Joint kinematics for the hip, stifle and tarsal joints and their average range of motion (ROM) values, and their 95% Confidence Interval (CI) values of kinematics curves are reported. Conclusions and Clinical Relevance-This study provides normative data of healthy GS dogs to form a preliminary basis in the analysis of the spatial-temporal parameters, kinematics and kinetics during quadrupedal stance posture and gait. Also, a new back movement protocol enabling a multi-segment back model is provided. Results show that the proposed gait analysis protocol may become a useful and objective tool for the evaluation of canine treatment with special focus on the back movement
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