Publicaciones

Affichage de 201 à 210 sur 1005

ART

Existence and percolation results for stopped germ-grain models with unbounded velocities

David Coupier, David Dereudre, Simon Le Stum

We investigate the existence and first percolation properties of general stopped germ-grain models. They are defined via a random set of germs generated by a homogeneous planar Poisson point process in R2. From each germ, a grain, composed of a random number of branches, grows. This grain stops...

Stochastic Processes and their Applications, 2021, 142, pp.549-579. ⟨10.1016/j.spa.2021.08.008⟩. ⟨hal-04396369⟩

THESE

Contribution au développement des capteurs de pression basés sur des dispositifs à onde acoustique de surface (SAW) pour des environnements sévères (hautes températures), Contribution to the development of pressure sensors based on surface acoustic wave (SAW) devices for severe environments (high temperatures)

Hassan Alhousseini

Depuis de nombreuses années, les ondes acoustiques de surface (SAW) sont utilisées dans les composants électroniques pour des applications industrielles (filtrage, traitement du signal) et pour la réalisation des capteurs. En raison de systèmes électroniques embarqués et de la possibilité de..., For many years surface acoustic waves (SAW) have been used in manufacturing electronic components for industrial and sensing applications. Due to the absence of an embedded electronic system and the possibility of wireless communication this technology can offer a great solution for sensing in...

Acoustique [physics.class-ph]. Université Polytechnique Hauts-de-France; Institut national des sciences appliquées Hauts-de-France, 2021. Français. ⟨NNT : 2021UPHF0044⟩. ⟨tel-03601410⟩

ART

Investigation of aluminum nitrate as a set retarder of magnesium potassium phosphate cement: Mechanisms involved in diluted suspension

Céline Cau Dit Coumes, Angélique Rousselet, Biwan Xu, Cyrille Albert-Mercier, sandrine Gauffinet

In this study, the influence of aluminum nitrate on the hydration process of magnesium potassium phosphate (MKP) cement was investigated experimentally and through thermodynamic modelling using diluted systems with Mg/PO$_4$ molar ratio and water-to-cement ratio of 1 and 100 respectively. Three...

Cement and Concrete Research, 2021, 150, pp.106608. ⟨10.1016/j.cemconres.2021.106608⟩. ⟨hal-04280341⟩

UNDEFINED

STABILIZATION OF COUPLED WAVE EQUATIONS WITH VISCOUS DAMPING ON CYLINDRICAL AND NON-REGULAR DOMAINS: CASES WITHOUT THE GEOMETRIC CONTROL CONDITION

Mohammad Akil, Haidar Badawi, Serge Nicaise, Virginie Régnier

In this paper, we investigate the direct and indirect stability of locally coupled wave equations with local viscous damping on cylindrical and non-regular domains without any geometric control condition. If only one equation is damped, we prove that the energy of our system decays polynomially...

2021. ⟨hal-03458856⟩

THESE

Optimisation du procédé d'impression par stéréolithographie de phosphate tricalcique béta, Optimisation of the stereolithography printing process of tricalcium phosphate

Chloé Goutagny

Les technologies de fabrication additive permettent la production rapide d’objets de forme complexe et trouvent un intérêt dans le domaine des soins à la santé, en particulier pour la fabrication d’implants osseux synthétiques. Les biocéramiques sont des matériaux de choix pour ce type d’implant...., The additive manufacturing technologies enable the fast production of objects with a complex shape and are particularly interesting in the medical field and the manufacture of synthetic bone implants. Bioceramics are materials of choice for this type of implant. Amongst them the hydroxyapatite and...

Matériaux. Université Polytechnique Hauts-de-France, 2021. Français. ⟨NNT : 2021UPHF0035⟩. ⟨tel-03592842⟩

COMM

Topological Optimization of Piezoelectric Structures for Low-frequency Energy Harvesting Applications

Madiha Yessari, Mohamed Rguiti, Abdelowahed Hajjaji, Najoua Fangachi, Abdezzahid Arbaoui

Recovering energy from ambient vibrating resources has been the subject of considerable research studies in the last decade. However, the vibrations found in the environment correspond to low frequencies, often below 200 Hz, and for small-scale applications and if the excitation is sinusoidal, the...

9th International Renewable and Sustainable Energy Conference (IRSEC), Nov 2021, Morocco, France. pp.1-6, ⟨10.1109/IRSEC53969.2021.9741205⟩. ⟨hal-04475226⟩

ART

Subdivisions of Ring Dupin Cyclides Using Bézier Curves with Mass Points

Lionel Garnier, Lucie Druoton, Jean-Paul Becar, Laurent Fuchs, Géraldine Morin

The paper deals in the Computer-Aided Design or Computer-Aided Manufacturing domain with the Dupin cyclides as well as the Bézier curves. It shows that the same algorithms can be used either for subdivisions of ring Dupin cyclides or Bézier curves. The Bézier curves are described with mass points...

WSEAS Transactions on Mathematics, 2021, 20, pp.581-597. ⟨10.37394/23206.2021.20.62⟩. ⟨hal-03521704⟩

ART

Influence of cetyltrimethylammonium bromide and hydroxide ions on the interfacial tension and stability of emulsions of dodecane in aqueous silicate solutions

Matthieu Bertin, Donatien Gomes Rodrigues, Christel Pierlot, Cyrille Albert-Mercier, Catherine Davy, David Lambertin, Véronique Rataj

This manuscript provides an understanding of the emulsification mechanisms of a model alkane (dodecane) in concentrated aqueous sodium silicate solutions, for e.g. formulating alkane/geopolymer composites for varied applications. To this purpose, we assume that silicate oligomers stabilize the...

Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2021, Colloids and Surfaces A: Physicochemical and Engineering Aspects, 628, 11 p. ⟨10.1016/j.colsurfa.2021.127306⟩. ⟨hal-04094024⟩

POSTER

Efficiency of the emulsification of organic liquids in alkali-activated materials for radioactive waste encapsulation purposes

Charles Reeb, David Lambertin, Catherine Davy, Cyrille Albert Mercier, Christel Pierlot

The encapsulation of a pure mineral oil (20%vol.) was successfully performed in alkali-activated materials (AAM), either based on metakaolin or blast furnace slag precursors. Surfactants are required to efficiently stabilize the emulsion of oil. Rheological characterizations of fresh pastes...

IAEA Radioactive Waste Management Conference 2021, Nov 2021, Vienne, Austria. ⟨cea-04726194⟩

THESE

Comparaison de techniques de frittage non-conventionnelles appliquées à la zircone et l'hydroxyapatite nanométriques, Comparison of non-conventional sintering techniques applied to nanometric zirconia and hydroxyapatite

Pierre Lefeuvre

L’amélioration de la compréhension des phénomènes de densification de poudres céramiques a conduit au développement de nouvelles technologies de frittage impliquant l’application d’une pression, d’un champ électrique ou de micro-ondes. Ces différentes techniques conduisent à des chemins de..., Better understanding of densification of ceramic powders led to the development of new sintering technologies using pressure, an electric field or microwaves. These new techniques have their own densification path and allow to obtain denser ceramics with a finer microstructure. A question that is...

Matériaux. Université Polytechnique Hauts-de-France, 2021. Français. ⟨NNT : 2021UPHF0033⟩. ⟨tel-03613040⟩