Search results for "surface"

Topological surface wave metamaterials for robust vibration attenuation and energy harvesting

2021

International audience; We propose topological metamaterials working in Hertz frequency range, constituted of concrete pillars on the soil ground in a honeycomb lattice. Based on the analog of the quantum valley Hall effect, a non-trivial bandgap is formed by breaking the inversion symmetry of the unit cell. A topological interface is created between two different crystal phases whose robustness against various defects and disorders is quantitatively analyzed. Finally, we take advantage of the robust and compact topological edge state for designing a harvesting energy device. The results demonstrate the functionality of the proposed structure for both robust surface vibration reduction and …

The use of barley straw residues to avoid high erosion and runoff rates on persimmon plantations in Eastern Spain under low frequency-high magnitude …

2016

[EN] Soil and water losses due to agricultural mismanagement are high and non-sustainable in many orchards. An experiment was set up with rainfall simulation at 78 mm h(-1) over 1 hour on 20 paired plots of 2 m(2) (bare and straw covered) in new persimmon plantations in Eastern Spain. Effects of straw cover on the control of soil and water losses were assessed. An addition of 60% straw cover (75 gm(-2)) resulted in delayed ponding and runoff generation and consequently reduced water losses from 60% to 13% of total rainfall. The straw cover reduced raindrop impact and thus sediment detachment from 1014 to 47 g plot(-1) h(-1). The erosion rate was reduced from 5.1 to 0.2 Mg ha-(1) h(-1). The …

Surface canal, squelette et espace des sphères

2016

A canal surface is the envelope of a one-parameter familly of oriented spheres. With the knowledge of center an radius functions associated to it, it is easy to compute a parametrisation of the surface. In this article, we study the inverse operation, which is the search for the spheres in the canal surface. By selecting a point on the boundary and using the sphere space, we estimate the maximal sphere tangent with this point and a second point on the boundary. Furthermore, we estimate a second sphere, which allows to build the characteiristic circle of the canal surface. So this article consists in a new approach of the skeletonization of an object. Indeed, a skeleton is a shape representa…

Análisis y valoración de los sistemas de evaluación de suelos en España. Evolución, tendencias actuales y perspectivas futuras

1997

23 páginas, 5 cuadros.

Euler Characteristics of Moduli Spaces of Curves

2005

Let ${mathcal M}_g^n$ be the moduli space of n-pointed Riemann surfaces of genus g. Denote by ${\bar {\mathcal M}}_g^n$ the Deligne-Mumford compactification of ${mathcal M}_g^n$. In the present paper, we calculate the orbifold and the ordinary Euler characteristic of ${\bar {\mathcal M}}_g^n$ for any g and n such that n>2-2g.

Comparative analysis of surface energy balance models for actual evapotranspiration estimation through remotely sensed images

2012

Stima da remoto delle caratteristiche evapotraspirative e di umidità del sistema suolo-vegetazione di un impianto viticolo su morfologia complessa

2009

Obiettivo della ricerca è la messa a punto di tecniche di elaborazione d’immagini telerilevate al fine di analizzare le caratteristiche evapotraspirative e di umidità del sistema suolo-vegetazione. La valutazione di tali grandezze è, infatti, di notevole interesse poiché consente alle aziende viticole di ottimizzare i processi di produzione nonché la qualità del prodotto. L’evapotraspirazione effettiva del sistema suolo-vegetazione (ETa) è stata stimata mediante l’applicazione del SEBAL (Surface Energy Balance Algorithm for Land), un modello di bilancio energetico facente uso d’immagini telerilevate nel campo riflessivo ed emissivo dello spettro. Il modello, implementato nella versione Moun…

Electron Irradiation Effects on Single‐Layer MoS 2 Obtained by Gold‐Assisted Exfoliation

2022

International audience; Mechanical exfoliation assisted by gold is applied to obtain good quality large lateral size single-layer MoS2. The effects of 2.5 MeV electron irradiation are investigated at room temperature on structural and electronic features by Raman and microluminescence spectroscopy. The exciton recombination emission in the direct bandgap of single-layer MoS2 is affected during irradiation starting from the minimum explored dose of 1 kGy. At higher doses, Raman bands show no relevant modifications whereas the exciton emission is quenched, suggesting that irradiation-induced point defects affect exciton dynamics.

Reversible Strong Coupling in Silver Nanoparticle Arrays Using Photochromic Molecules

2012

International audience; In this Letter, we demonstrate a reversible strong coupling regime between a dipolar surface plasmon resonance and a molecular excited state. This reversible state is experimentally observed on silver nanoparticle arrays embedded in a polymer film containing photochromic molecules. Extinction measurements reveal a clear Rabi splitting of 294 meV, corresponding to ∼13% of the molecular transition energy. We derived an analytical model to confirm our observations, and we emphasize the importance of spectrally matching the polymer absorption with the plasmonic resonance to observe coupled states. Finally, the reversibility of this coupling is illustrated by cycling the …

The Association between Masticatory Muscles Activation and Foot Pressure Distribution in Older Female Adults: A Cross-Sectional Study

2023

The association between craniofacial muscles and postural control is well-known because of numerous anatomical connections. However, there are a few conflicting studies that correlated the activity of the masticatory muscles with the distribution of body weight pressure on the feet, which can strongly influence balance. Therefore, the purpose of our study was to evaluate the association between the masseter and temporalis muscle activity and foot pressure distribution. Fifty-two women were recruited, and baropodometric and EMG analyses of the masseter and temporalis baseline activities were analyzed. An ipsilateral association was found between the right temporal muscle activity and the rig…