64,650 research outputs found
“Lingua e integrazione”
No full textI recenti fenomeni migratori hanno riportato all’attualità lo studio dei modelli di integrazione fra i popoli. In quest’ambito la ricerca nel campo della didattica della lingua straniera riveste un ruolo centrale poiché studia gli approcci, i metodi e le tecniche didattiche più efficaci per promuovere l’apprendimento di una lingua che sia strumento d’integrazione nella nuova realtà socio-culturale nella quale il migrante77 inizia la propria esperienza. Questo contributo propone alcune riflessioni sul legame tra lingua e identità culturale, partendo dalla normativa italiana che disciplina la rimozione degli ostacoli relativi alla lingua e approfondendo le problematiche legate allo shock interculturale. Il presupposto è che la lingua rivesta un ruolo fondamentale come strumento d’integrazione perché consente all’individuo di conoscere la realtà che lo circonda e di farsi conoscere tramite la narrazione del sé. La nuova lingua del paese ospitante può dunque rappresentare un ostacolo ma anche, se appresa, abbattere molte di quelle barriere ideologiche che ostacolano la piena integrazione
Improved technique for the measurement of the kinetics of Ca2+ uptake by cells: The coupling of an amplifier with voltage regulator to a Ca2+-selective electrode.
No full textThe kinetics of extremely small variations of Ca2+ concentration in a solution containing 1 mM CaCl2 can be accurately measured by placing an amplifier with voltageregulator in series with a Ca2+-selective electrode and a potentiometric recorder
Posebnosti urbanih flora u Hrvatskoj
No full textUrbanizacija je jedan od najekstremnijih procesa preinake staništa koji je nastao pod utjecajem čovjeka. Antropogenim utjecajem došlo je do značajnih promjena u florama urbanih središta. Promjene u ekosustavu održavaju se na cjelokupno područje uključujući klimatske uvjete sredine, biljnu i životinjsku populaciju, a sukladno tome, javljaju se invazivne vrste kao neposredna posljedica urbanizacije. Stoga se urbanim florama u posljednje vrijeme posvećuje puno pažnje. Cilj rada je analizirati različita istraživanja urbanih flora u pojedinim gradovima kontinentalne i jadranske Hrvatske. U radu se opisuju njihove značajke s obzirom na područje u kojem su prisutne
Korovna flora vinograda
No full textKorovna flora vinograda dijeli se s gledišta sezonske dinamike nicanja na zimsko-proljetne (ozime), proljetno-ljetne i kasnoljetne korove. Ozimi korovi imaju prostratni tip rasta, niskog su habitusa i najčešće ne nanose štete jer je vinova loza u vrijeme njihova razvoja u fazi mirovanja. Najveće štete nanose proljetno-ljetni i kasnoljetni korovi. Štete od korova mogu biti izravne i neizravne. Izravne štete (oduzimanje hraniva, vode, svjetlosti i prostora) više su izražene u mladom nasadu, a neizravne štete više su izražene u etabliranu nasadu (ometaju aplikaciju sredstava za zaštitu, usporavaju provjetravanje i cirkulaciju zraka u nasadu, domaćini su štetnim makro i mikroorganizmima, i dr.)
Korovna flora vinograda
No full textKorovna flora vinograda dijeli se s gledišta sezonske dinamike nicanja na zimsko-proljetne (ozime), proljetno-ljetne i kasnoljetne korove. Ozimi korovi imaju prostratni tip rasta, niskog su habitusa i najčešće ne nanose štete jer je vinova loza u vrijeme njihova razvoja u fazi mirovanja. Najveće štete nanose proljetno-ljetni i kasnoljetni korovi. Štete od korova mogu biti izravne i neizravne. Izravne štete (oduzimanje hraniva, vode, svjetlosti i prostora) više su izražene u mladom nasadu, a neizravne štete više su izražene u etabliranu nasadu (ometaju aplikaciju sredstava za zaštitu, usporavaju provjetravanje i cirkulaciju zraka u nasadu, domaćini su štetnim makro i mikroorganizmima, i dr.)
A Dynamic Subfilter-scale Stress Model for Large Eddy Simulations Based on Physical Flow Scales
No full textWe propose a new definition of the length scale in an eddy-viscosity model for large-eddy simulations (LES). This formulation extends and generalizes a previous proposal [Piomelli, Rouhi and Geurts, Proc. ETMM10, 2014], in which the LES length scale was expressed in terms of the integral length-scale of turbulence determined by the flow characteristics and explicitly decoupled from the simulation grid; this approach was named Integral Length-Scale Approximation (ILSA). As in the original ILSA, the model coefficient was determined by the user, and required to maintain a desired contribution of the unresolved, subfilter scales (SFS) to the global transport. We propose a local formulation (local ILSA) in which the model coefficient is local in space, allowing a precise control over SFS activity as a function of location. This new formulation preserves the properties of the global model; application to channel flow and backward-facing step verifies its features and accuracy
Large-eddy simulation of a separated flow with a sub-filter scale model based on the integral length-scale
No full textA new sub-filter scale model for large-eddy simulations, which uses a length-scale proportional to the integral scale of the turbulence instead of the grid resolution to parametrize the modelled stresses, will be assessed in the prediction of the flow of a boundary-layer over a rough surface, which includes separation and reattachment
Near Wall PIV-Measurements on the Windward Slope of a Hill
No full textThe turbulent flow over periodic hills was measured near to the wall, using planar Particle-Image-Velocimetry (PIV) at high spatial resolution. Our focus is on the near wall turbulence structure on the windward slope of the hill. For large-eddy simulation (LES) we suspect that, if this was not predicted accurately, it affects the prediction of the velocity profiles over the hill crest which in turn will affect the recirculation length downstream of the hill. Regarding the time averaged velocities, we were able to resolve the linear viscous region of the boundary layer. The velocity distribution and also the Reynolds stress does not comply with the law of the wall as it is valid for a turbulent boundary layer at equilibrium
Thermal and geochemical investigation of ice wedges in Northern Victoria Land (Antartica)
No full textEnergy dissipation and flux laws for unsteady turbulence
No full textDirect Numerical Simulations of spatially periodic unsteady turbulence show that the high Reynolds number scalings of the instantaneous energy dissipation rate and interscale energy flux at intermediate wavenumbers are qualitatively different from the well-known cornerstone scalings of equilibrium turbulence where and are time-dependent rms velocity and integral length-scales. Instead, they both scale as where and are length and velocity scales characterizing initial/overall unsteady turbulence conditions
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