Détail de l'auteur
Auteur Samia Bouhedja |
Documents disponibles écrits par cet auteur (4)
Affiner la recherche Interroger des sources externes"Etude des Propriétés Mécaniques et de L’atténuation des Ondes de Surface dans le Si Poreux en Utilisant un Capteur à Lentilles Annulaires"
Titre : "Etude des Propriétés Mécaniques et de L’atténuation des Ondes de Surface dans le Si Poreux en Utilisant un Capteur à Lentilles Annulaires" Type de document : texte imprimé Auteurs : Samia Bouhedja, Directeur de thèse ; Touraya Bouchemat -Boumaza, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2014 Importance : 134 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : "Atténuation, Microscopie acoustique (SAM), Silicium poreux, FFT, signature
acoustique V(z), constantes élastiques, vitesses de propagation des ondes, Crack, Alumine poreuse,
champ noir."
"Attenuation, acoustic microscopy (SAM), porous silicon, FFT, acoustic signature V (z), elastic constants, Velocity
of wave propagation, Crack, porous alumina, Dark field."
التخفيف، المجهري الصوتي(SAM)السيلكون المسامي F.F.T لبصمة الصوتية V (z) ثوابت المرونة ،سرعةانتشار الموجات، الصدع، الألومينا المسامية، أسود الميدان.Index. décimale : 621 Electronique Résumé : "The investigation of the characteristics of acoustic wave surface propagation in homogeneous materials, by
application of the acoustic microscopy, is subjected to a big request in scientific research. This request orientated
research to the characterization of the porous materials.
Our objective consists in studying structure and calculating the acoustical parameters of porous silicon (PSi) by
using the quantitative acoustic microscopy. For it we simulate the curves of the output signal of the sign of exit
cited acoustical material signature, V (z), to study the evolution of different acoustical parameters as well as
microstructure of PSi according to the porosity.
At first, we represented all tools necessary for the application of the quantitative acoustic microscopy and cited the
different application domains. Subsequently we represented the porous materials in general and porous silicon
particularly. In this section the quantitative investigation, in dark field, allowed us to found that the decrease of the
energy distribution at the transducer strongly affects both the amplitude of the acoustic signatures that their periods
tend to infinite values when the occultation reaches a threshold. This angle threshold is generally right before the
critical angle of excitation of the mode of Rayleigh, θR. A slip of this last towards the great values, excited by the
presence of air in the pores, appears when porosity increases.
After this study, we have been interested to the attenuation of the surface wave propagation in PSi by using three
different methods. The first method is the analytical method, which is obtained by solving the Viktorov equation.
The second method is that of the spectral analysis, where the fast Fourier transform (FFT) is applied to the curves V
(Z). The last method uses the dark field. The results obtained by simulation in good agreement with those
experimental found in the literature.
Another area of interest is to study the influence of crack on the propagation acoustic waves. The presence of the
crack to the material surface disturbs the wave propagation as it modifies the amplitude of the reflection coefficient.
To investigate the latter we used the model Schoch. Our study shows that there is a reduction of 27%. Thus by
taking in consideration the approximation of Rayleigh and modeling the acoustic signature V (Z), we find that the
output signal decreases by 29.3% in presence of the crack.
In the last part of this thesis we applied our calculations to porous alumina (PAl2O3). We showed that the acoustic
technique is a very powerful nondestructive method to characterize this type of biomaterials. We noted that as a
given porosity, when the frequency increases the attenuation increases, and at a given frequency, when porosity
increases, attenuation becomes stronger. The curves of V (z) are a key for the microstructural investigations of
PAl2O3 with an aim of establishing empirical relationships between the acoustic parameters and compare them to
those reported in the literature."
Diplôme : Doctorat en sciences En ligne : ../theses/electronique/HAM6521.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=9613 "Etude des Propriétés Mécaniques et de L’atténuation des Ondes de Surface dans le Si Poreux en Utilisant un Capteur à Lentilles Annulaires" [texte imprimé] / Samia Bouhedja, Directeur de thèse ; Touraya Bouchemat -Boumaza, Directeur de thèse . - constantine [Algérie] : Université Constantine 1, 2014 . - 134 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : "Atténuation, Microscopie acoustique (SAM), Silicium poreux, FFT, signature
acoustique V(z), constantes élastiques, vitesses de propagation des ondes, Crack, Alumine poreuse,
champ noir."
"Attenuation, acoustic microscopy (SAM), porous silicon, FFT, acoustic signature V (z), elastic constants, Velocity
of wave propagation, Crack, porous alumina, Dark field."
التخفيف، المجهري الصوتي(SAM)السيلكون المسامي F.F.T لبصمة الصوتية V (z) ثوابت المرونة ،سرعةانتشار الموجات، الصدع، الألومينا المسامية، أسود الميدان.Index. décimale : 621 Electronique Résumé : "The investigation of the characteristics of acoustic wave surface propagation in homogeneous materials, by
application of the acoustic microscopy, is subjected to a big request in scientific research. This request orientated
research to the characterization of the porous materials.
Our objective consists in studying structure and calculating the acoustical parameters of porous silicon (PSi) by
using the quantitative acoustic microscopy. For it we simulate the curves of the output signal of the sign of exit
cited acoustical material signature, V (z), to study the evolution of different acoustical parameters as well as
microstructure of PSi according to the porosity.
At first, we represented all tools necessary for the application of the quantitative acoustic microscopy and cited the
different application domains. Subsequently we represented the porous materials in general and porous silicon
particularly. In this section the quantitative investigation, in dark field, allowed us to found that the decrease of the
energy distribution at the transducer strongly affects both the amplitude of the acoustic signatures that their periods
tend to infinite values when the occultation reaches a threshold. This angle threshold is generally right before the
critical angle of excitation of the mode of Rayleigh, θR. A slip of this last towards the great values, excited by the
presence of air in the pores, appears when porosity increases.
After this study, we have been interested to the attenuation of the surface wave propagation in PSi by using three
different methods. The first method is the analytical method, which is obtained by solving the Viktorov equation.
The second method is that of the spectral analysis, where the fast Fourier transform (FFT) is applied to the curves V
(Z). The last method uses the dark field. The results obtained by simulation in good agreement with those
experimental found in the literature.
Another area of interest is to study the influence of crack on the propagation acoustic waves. The presence of the
crack to the material surface disturbs the wave propagation as it modifies the amplitude of the reflection coefficient.
To investigate the latter we used the model Schoch. Our study shows that there is a reduction of 27%. Thus by
taking in consideration the approximation of Rayleigh and modeling the acoustic signature V (Z), we find that the
output signal decreases by 29.3% in presence of the crack.
In the last part of this thesis we applied our calculations to porous alumina (PAl2O3). We showed that the acoustic
technique is a very powerful nondestructive method to characterize this type of biomaterials. We noted that as a
given porosity, when the frequency increases the attenuation increases, and at a given frequency, when porosity
increases, attenuation becomes stronger. The curves of V (z) are a key for the microstructural investigations of
PAl2O3 with an aim of establishing empirical relationships between the acoustic parameters and compare them to
those reported in the literature."
Diplôme : Doctorat en sciences En ligne : ../theses/electronique/HAM6521.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=9613 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité HAM/6521 HAM/6521 Thèse Bibliothèque principale Thèses Disponible
Titre : Etude des vitesses des ondes de surface et de l'atténuation du mode de Rayleigh via un capteur fonctionnant en champ noir Type de document : texte imprimé Auteurs : Samia Bouhedja ; Univ. de Constantine, Éditeur scientifique ; Z. Hadjoub, Directeur de thèse Année de publication : 2006 Importance : 107 f. Note générale : 01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Capteur Microscopie acoustique Ondes de surface Champ noir Lentille annulaire Constantes élastiques Atténuation Index. décimale : 530 Physique En ligne : ../theses/physique/BOU4453.pdf Permalink : index.php?lvl=notice_display&id=3578 Etude des vitesses des ondes de surface et de l'atténuation du mode de Rayleigh via un capteur fonctionnant en champ noir [texte imprimé] / Samia Bouhedja ; Univ. de Constantine, Éditeur scientifique ; Z. Hadjoub, Directeur de thèse . - 2006 . - 107 f.
01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Capteur Microscopie acoustique Ondes de surface Champ noir Lentille annulaire Constantes élastiques Atténuation Index. décimale : 530 Physique En ligne : ../theses/physique/BOU4453.pdf Permalink : index.php?lvl=notice_display&id=3578 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/4453 BOU/4453 Thèse Bibliothèque principale Thèses Disponible
Titre : Interaction acousto-optique dans les micro et nano structures périodiques. Type de document : texte imprimé Auteurs : Mohamed Lamine Bouchemal, Auteur ; Samia Bouhedja, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 94 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : Electronique: Optique Bande interdite Modes de cavité Cristaux photoniques Cristaux phononiques Couplage acousto-optique Comsol Multiphysics Band gap Cavity modes Photonic crystals Phononic crystals Acousto-optical
coupling فجوة النطاق أنماط التجويف البلورات الفوتونية البلورات الصوتية التوصيل البصري الصوتي ComIndex. décimale : 621 Electronique Résumé :
Phoxonic structures (also called phononic-photonic) consist of a periodicity in the refractive index and acoustic impedance in a systematic way and confine acoustic and electromagnetic waves.They lead to new acousto-optical or optomechanical applications. The main objective of this work is to model a crystal that allows the coupling of photonic and phononic band gap phenomena in order to study the acousto-optical interactions that can occur in anoptomechanical cavity by inserting a silicon disc of radius ri. insideinclusions. This analogy between optics and acoustics allows us, on one hand, to increase the efficiency of the insulators and on the other hand, to improve the acoustic characteristics and optimize the electromechanical performances of certain types of transducers used in medical imaging. The simulation of the gap according to the geometric parameters using the COMSOL MULTIPHYSICS software based on the finite element method has shown that the internal radius value ri = r/2 is optimal to obtain a maximum phononic and photonic (TM) width of 75% and 15% simultaneously. This opening obtained from Silicon remains the best compared to gaps of aluminum, SiO2 and epoxy. Finally a thorough study on transmission (results in accordance with the literature) was carried out and has shown another form of investigating of the band gap that confirmed the choice of the inner radius value. The width of the absolute band gap obtained by inserting an internal disc withoptimized radius ri = r/2insures the presence of a large number of well localized modes with a high quality factor which can reach 105. In conclusion, the phoxonic cavity designed with a high quality factor can be used to improve the acousto-optical interaction.Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BOU7410.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11062 Interaction acousto-optique dans les micro et nano structures périodiques. [texte imprimé] / Mohamed Lamine Bouchemal, Auteur ; Samia Bouhedja, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 94 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : Electronique: Optique Bande interdite Modes de cavité Cristaux photoniques Cristaux phononiques Couplage acousto-optique Comsol Multiphysics Band gap Cavity modes Photonic crystals Phononic crystals Acousto-optical
coupling فجوة النطاق أنماط التجويف البلورات الفوتونية البلورات الصوتية التوصيل البصري الصوتي ComIndex. décimale : 621 Electronique Résumé :
Phoxonic structures (also called phononic-photonic) consist of a periodicity in the refractive index and acoustic impedance in a systematic way and confine acoustic and electromagnetic waves.They lead to new acousto-optical or optomechanical applications. The main objective of this work is to model a crystal that allows the coupling of photonic and phononic band gap phenomena in order to study the acousto-optical interactions that can occur in anoptomechanical cavity by inserting a silicon disc of radius ri. insideinclusions. This analogy between optics and acoustics allows us, on one hand, to increase the efficiency of the insulators and on the other hand, to improve the acoustic characteristics and optimize the electromechanical performances of certain types of transducers used in medical imaging. The simulation of the gap according to the geometric parameters using the COMSOL MULTIPHYSICS software based on the finite element method has shown that the internal radius value ri = r/2 is optimal to obtain a maximum phononic and photonic (TM) width of 75% and 15% simultaneously. This opening obtained from Silicon remains the best compared to gaps of aluminum, SiO2 and epoxy. Finally a thorough study on transmission (results in accordance with the literature) was carried out and has shown another form of investigating of the band gap that confirmed the choice of the inner radius value. The width of the absolute band gap obtained by inserting an internal disc withoptimized radius ri = r/2insures the presence of a large number of well localized modes with a high quality factor which can reach 105. In conclusion, the phoxonic cavity designed with a high quality factor can be used to improve the acousto-optical interaction.Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BOU7410.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11062 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/7410 BOU/7410 Thèse Bibliothèque principale Thèses Disponible
Titre : Modélisation de la propagation ultrasonore dans les milieux complexes Type de document : texte imprimé Auteurs : Lyes Dib, Auteur ; Samia Bouhedja, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2016 Importance : 107 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : Matériaux poreux modèle de Biot-Allard matrice de transfert Comsol Multiphysics Coefficient d’absorption mousse polymère porous materials Biot-Allard model transfer matrix absorption coefficient polymer foam المواد المسامیة نموذج) (Biot-Allardالمصفوفة المحولة Comsol multiphysicsمعامل
الامتصاص رغوة البولیمرIndex. décimale : 621 Electronique Résumé : This thesis work aims at modeling the propagation of sound waves in complex medium, or
porous materials, and the study of sound absorption of these materials to reduce the noise generated by manufactures. Poroelastic materials are porous materials in the case where the structure is set in motion, that are to say the structure is deformable or movable. The theory of Biot-Johnson-Chompoux-Allard (or model of generalized Biot-Allard) is used to describe the behavior of these poro-viscoelastic materials modeled as two-phase systems consisting of a solid phase and a fluid phase, air, coupled with time and space.
An analytical approach is proposed in the context of the generalized Biot-Allard theory. This approach is a method of the transfer matrix. Acoustic indicators were calculated from this method.
A numerical approach based on the finite elements is used to calculate the real and imaginary part of the surface impedance and the absorption coefficient, using a calculated code called COMSOL Multiphysics.
A comparison between the simulations used by the two approaches was made to calculate the acoustic indicators. But also the effects of mechanical parameters of sound absorption were studied. A notable effect was observed in the case the Young’s modulus parameter, but nothing has been observed for other parameters.
Diplôme : Doctorat en sciences En ligne : ../theses/electronique/DIB6918.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10270 Modélisation de la propagation ultrasonore dans les milieux complexes [texte imprimé] / Lyes Dib, Auteur ; Samia Bouhedja, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2016 . - 107 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : Matériaux poreux modèle de Biot-Allard matrice de transfert Comsol Multiphysics Coefficient d’absorption mousse polymère porous materials Biot-Allard model transfer matrix absorption coefficient polymer foam المواد المسامیة نموذج) (Biot-Allardالمصفوفة المحولة Comsol multiphysicsمعامل
الامتصاص رغوة البولیمرIndex. décimale : 621 Electronique Résumé : This thesis work aims at modeling the propagation of sound waves in complex medium, or
porous materials, and the study of sound absorption of these materials to reduce the noise generated by manufactures. Poroelastic materials are porous materials in the case where the structure is set in motion, that are to say the structure is deformable or movable. The theory of Biot-Johnson-Chompoux-Allard (or model of generalized Biot-Allard) is used to describe the behavior of these poro-viscoelastic materials modeled as two-phase systems consisting of a solid phase and a fluid phase, air, coupled with time and space.
An analytical approach is proposed in the context of the generalized Biot-Allard theory. This approach is a method of the transfer matrix. Acoustic indicators were calculated from this method.
A numerical approach based on the finite elements is used to calculate the real and imaginary part of the surface impedance and the absorption coefficient, using a calculated code called COMSOL Multiphysics.
A comparison between the simulations used by the two approaches was made to calculate the acoustic indicators. But also the effects of mechanical parameters of sound absorption were studied. A notable effect was observed in the case the Young’s modulus parameter, but nothing has been observed for other parameters.
Diplôme : Doctorat en sciences En ligne : ../theses/electronique/DIB6918.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10270 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité DIB/6918 DIB/6918 Thèse Bibliothèque principale Thèses Disponible
