DEM simulation of percolating particles in binary mixtures

openThe aim of the thesis is to study the phenomenon of discharging of binary mixtures of granular material in order to better understand the percolation mechanism, which consists of the relative movement of small particles moving through the void space between the larger ones. The studied system consists of a silo which is filled with the binary mixture and subsequently discharged in funnel flow. The investigation was conducted using the LIGGGHTS simulator through which it was possible to represent the filling and discharging behavior of the granular material mixtures using DEM approach. In the first part of the thesis, the percolation phenomenon and the DEM approach are presented; then, will be described the parametric analysis conducted to find the parameters to introduce in DEM simulations. Finally, several simulations were conducted using binary mixtures with different diameter ratios and different compositions. The data obtained from the simulations were processed and compared with the experimental data in order to validate the results achieved.The aim of the thesis is to study the phenomenon of discharging of binary mixtures of granular material in order to better understand the percolation mechanism, which consists of the relative movement of small particles moving through the void space between the larger ones. The studied system consists of a silo which is filled with the binary mixture and subsequently discharged in funnel flow. The investigation was conducted using the LIGGGHTS simulator through which it was possible to represent the filling and discharging behavior of the granular material mixtures using DEM approach. In the first part of the thesis, the percolation phenomenon and the DEM approach are presented; then, will be described the parametric analysis conducted to find the parameters to introduce in DEM simulations. Finally, several simulations were conducted using binary mixtures with different diameter ratios and different compositions. The data obtained from the simulations were processed and compared with the experimental data in order to validate the results achieved

Phenomenology and Semiotics. Crossing Perspectives.

In recent years the study of relationships between semiotics and phenomenology seems to be entering a period of renewed vitality and creativity (CADIOT & VISETTI 2001; ROSENTHAL & VISETTI 2008; 2010; PIOTROWSKI 2009; FONTANILLE 2008; BONDÌ 2012). For a variety of theoretical and historical reasons, there has been a constant osmosis between phenomenological and semiotic methods. In short, on one side, the works and investigations of phenomenologists have provided essential tools to semiotics. To give just an example: the greimasian semiotics theory refers to the process of meaning formation in terms of perceptual apprehension thanks to his original recovery of Merleau-Ponty’s perception theory. On the other, and at the same time, phenomenology is engaged in describing the activity of language and, in particular, the speaking activity (prise de la parole) of a subject which is a “beingin- the-world” (être-au-monde) and a “being-in-the-language” (être-au-langage): this is the paradigmatic case of Merleau-ponty and of his own model of linguistic gesture as emblem of expression. Furthermore, and more deeply, phenomenology and semiotics are methods rather than disciplines (BORDRON 2011). By means of the epoché, phenomenology has tried to return the articulation of the sensible and of the intelligible, and, on the other, the connections between subjectivity and intersubjectivity. Similarly, semiotics has proposed methods of analysis that are applicable to a wide range of domains:from narrative values to social identities, from textual traces to cultural practices with particular reference to their conditions of emergence. In this simultaneously archaeological and constructive orientation, phenomenology and semiotics have brought new challenges concerning the description of the phases of the meaning constitution

Filosofia e storiografia nel dibattito anglo-americano sulla svolta linguistica

This book proposes a critical examination of the main approaches of contemporary historiography, with the aim of bringing out their latent conceptual structures. Reinhart Koselleck wrote that «Historical knowledge always focuses on something more than what is found in the sources»: it is all about making its theories and values explicit, as they are also particular and historical facts themselves, which have clumsily been raised to universal principles. The author brings to light the pre-eminent forms of our relationship with the past through an analysis going from historiography to philosophy - from Pierre Nora, Carlo Ginzburg, Lynn Hunt to Hayden White, Jacques Derrida, Frank Ankersmit; from the New Cultural History and the histoire de la mémoire to the narrativism and to the philosophies of the historical sublime. Going beyond speculation, it is perhaps possible to aspire to a new alliance between historical and philosophical thought, to delimit a “middle space” between the unstructured praxism of a historiography without philosophy to the excessive idealism of a philosophy without history

Effects of cysteinyl-leukotriene receptors' antagonism by montelukast on lung mechanics and olfactory system histology in healthy mice.

Context: At variance with steroid administration, the possible effects of leukotrienes inhibition on basal respiratory mechanics and olfactory system function are still unclear.Objective: To investigate if interference with the leukotrienes activity may influence basal lung mechanics in healthy mammals, as well as the olfactory system.Materials and methods: We measured lung mechanics by the end-inflation occlusion method in control and in montelukast i.p. treated anaesthetised healthy mice (10 mg/kg/die for a week). A study of olfactory system histology was also conducted.Results: Elastance and resistive properties of the lung were not affected by montelukast, while a significant increment of lung hysteresis was observed. The analysis of olfactory system histology revealed no significant effects of montelukast compared to controls.Discussion and conclusions: Leukotrienes' antagonism does not affect respiratory mechanics in basal conditions, except for a hysteresis increment, which might counteract the inc..

I rapporti di filosofia storia e psicologia in H. Steinthal. Appendice: H. Steinthal, I tipi e le forme dell’interpretazione, trad. a cura di D.Bondì

Until now, critics have dealt with Steinthal’s work in terms of his contributions to the Kulturwissenschaft (Bumann, Meschiari, Trautmann-Waller), linguistics (Trabant, Ringmacher) and semantics theory (Formigari, Knobloch). This study focuses on the philosophy supporting his linguistic-psychological theories. Connections established between philosophy, philology and psychology demonstrate Steinthal’s originality in the Nineteenth-century debate on history, his contiguity with/difference to Böckh. Keywords: philology, psychology, gnosis, anagnosi

Assessing short- and long-term modifications of steady-state water infiltration rate in an extensive Mediterranean green roof

Green roof detention capacity is related to the steady-state infiltration rate, is, of the growing medium. With the aim to investigate short- and long-term modifications of the detention capacity of an extensive Mediterranean green roof, three mini-disk infiltrometer (MDI) measurement campaigns were conducted at construction, after one season and after five years of operation. A laboratory experiment was designed to separately measure is in the upper and the lower part of the substrate profile. During the first operating season, field is increased by a factor of 2.4 and 1.9 for near-saturated (applied pressure head, h0 = -30 mm) and quasi-saturated conditions (h0 = -5 mm), respectively. Similar rainfall height did not induce significant modifications in the upper layer of the laboratory columns, even if contribution of small pores to water infiltration tended to increase. Differently, is significantly decreased by a factor of 3.4-5.3 in the lower layer. After the simulated rainfall, the upper layer was less packed (mean bulk density, & rho;b = 1.083 kg m-3) and the lower layer was more packed (& rho;b = 1.218 kg m-3) as compared with the initial density (& rho;b = 1.131 kg m-3) and the lower part enriched in small particles. Short-term modifications in the experimental plot were thus attributed to fine particles washing-off and bulk density decrease in the upper layer, yielding an overall more conductive porous medium. After five years of green roof operation, field is did not further increase thus showing that the washing/clogging mechanism was complete after one season or it was masked by counteracting processes, like root development and hydrophobicity

Die Lebensmission der Familie

Bračna ljubav u sakramentu ženidbe znak je ljubavi koja ujedinjuje Krista zaručnika s njegovom zaručnicom, Crkvom. U žrtvi samoga sebe, koju Isus na križu vrši za svoju zaručnicu, otkriva se izvorna istina braka i obitelji po Božjem naumu. Suočena sa širenjem kulture smrti, koja teži promicanju individualizma i utilitarizma, ne poštujući nerazrješivost ujedinjujućeg i prokreativnog značenja bračne ljubavi, obitelj je pozvana sijati klice nade te prihvaćati i prenositi evanđelje života, oslobađajući svoj misionarski dinamizam za hrabro svjedočenje.Eheliebe im Sakrament der Eheschließung sei ein Zeichen der Liebe, die Christ den Verlobten mit seiner Verlobten Kirche vereinigt. Im Opfer seiner selbst, das Christ am Kreuz für seine Verlobte verrichtet, wird die ursprüngliche Wahrheit der Ehe und Familie nach dem Vorsatz Gottes enthüllt. Konfrontiert mit der Erweiterung der Kultur des Todes, welches nach der Beförderung des Individualismus und Utilitarismus strebt, die Unlösbarkeit der vereinigenden und prokreativen Bedeutung der Eheliebe nicht respektierend, sei die Familie berufen die Keime der Hoffnung zu säen, wie auch das Evangelium des Lebens zu akzeptieren und weiterzugeben, befreiend ihren missionarischen Dynamismus zum tapferen Zeuge

First application of the n − Be 9 optical potential to the study of the Be 10 continuum via the ( O 18 , O 17 ) neutron-transfer reaction

The $^{9}\mathrm{Be}(^{18}\mathrm{O},^{17}\mathrm{O})^{10}\mathrm{Be}$ reaction has been studied at an incident energy of 84 MeV, and the ejectiles have been detected at forward angles. The $^{10}\mathrm{Be}$ excitation energy spectrum has been obtained up to about 18 MeV, and several known bound and resonant states of $^{10}\mathrm{Be}$ have been identified. Calculations that describe the interaction of the neutron removed from the $^{18}\mathrm{O}$ projectile with the $^{9}\mathrm{Be}$ target by means of an optical potential with a semiclassical approximation for the relative motion account for a significant part of the $^{10}\mathrm{Be}$ continuum. Two parametrizations of the optical-model potential for the system n\text{\ensuremath{-}}^{9}\mathrm{Be} have been used and compared