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Partager le résultat de cette recherche Interroger des sources externesContribution au CND par l’utilisation des signaux électromagnétiques véhiculés. / Hamza Boudjefdjouf
Titre : Contribution au CND par l’utilisation des signaux électromagnétiques véhiculés. Type de document : texte imprimé Auteurs : Hamza Boudjefdjouf, Auteur ; Rabia Mehasni, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 125 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Electro-techniqueTags : Réflectométrie équations des télégraphistes propagation TEM problème direct problème inverse HR-FDTD paramètres linéique R, L, G et C, jonction en T Reflectometry telegrapher’s equations TEM propagation direct problem inverse problem p.u.l RLGC T junction Index. décimale : 622 Electro-Technique Résumé :
This thesis focuses on fault diagnosis of wired electrical networks using reflectometry. To develop diagnosis algorithms; we have studied both, direct problem (based on numerical simulations of electrical networks) and the inverse problem (which allows obtaining the network parameters from its measurements). For the direct problem, a very High Resolution Finite Difference Time Domain (HR-FDTD) method can be used to simulate how a given electrical transmission network is affected by hard/soft faults with enough fidelity. However, such process requires heavy and costly computational resources. A valid alternative to the FDTD based model relies on the use of a quicker and more efficient analytical based approach. For instance, the wired electric networks supporting a TEM propagation mode can be easily modeled by solving the transmission line telegrapher equations. Since the precision of the optimization algorithm in identifying the fault location and topology requires a model sensitively similar to the considered network, the key step remains the precise evaluation of the p.u.l RLGC parameters of the cable. A further improvement of the model accuracy consists in the modeling of the parasitic inductance associated to the T-junction. Finally, the ultimate goal of the highly realistic forward modeling being the inversion, it is important to know that reflectographs obtained by forward modeling are generally difficult to interpret, and they are not self-explanatory. For this purpose, multiple iterations are required, and thus, an efficient optimization algorithm is introduced in this dissertation, which is able to treat the inverse problem, and to identify any abnormality affecting the network in a short computational time. The methodologies and algorithms proposed in this thesis are validated either by numerical simulations or by real measurements.Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/electrotec/BOU7409.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11061 Contribution au CND par l’utilisation des signaux électromagnétiques véhiculés. [texte imprimé] / Hamza Boudjefdjouf, Auteur ; Rabia Mehasni, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 125 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Electro-techniqueTags : Réflectométrie équations des télégraphistes propagation TEM problème direct problème inverse HR-FDTD paramètres linéique R, L, G et C, jonction en T Reflectometry telegrapher’s equations TEM propagation direct problem inverse problem p.u.l RLGC T junction Index. décimale : 622 Electro-Technique Résumé :
This thesis focuses on fault diagnosis of wired electrical networks using reflectometry. To develop diagnosis algorithms; we have studied both, direct problem (based on numerical simulations of electrical networks) and the inverse problem (which allows obtaining the network parameters from its measurements). For the direct problem, a very High Resolution Finite Difference Time Domain (HR-FDTD) method can be used to simulate how a given electrical transmission network is affected by hard/soft faults with enough fidelity. However, such process requires heavy and costly computational resources. A valid alternative to the FDTD based model relies on the use of a quicker and more efficient analytical based approach. For instance, the wired electric networks supporting a TEM propagation mode can be easily modeled by solving the transmission line telegrapher equations. Since the precision of the optimization algorithm in identifying the fault location and topology requires a model sensitively similar to the considered network, the key step remains the precise evaluation of the p.u.l RLGC parameters of the cable. A further improvement of the model accuracy consists in the modeling of the parasitic inductance associated to the T-junction. Finally, the ultimate goal of the highly realistic forward modeling being the inversion, it is important to know that reflectographs obtained by forward modeling are generally difficult to interpret, and they are not self-explanatory. For this purpose, multiple iterations are required, and thus, an efficient optimization algorithm is introduced in this dissertation, which is able to treat the inverse problem, and to identify any abnormality affecting the network in a short computational time. The methodologies and algorithms proposed in this thesis are validated either by numerical simulations or by real measurements.Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/electrotec/BOU7409.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11061 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/7409 BOU/7409 Thèse Bibliothèque principale Thèses Disponible
Titre : Contribution à l’élaboration d’un modèle electromagnétique de supports de transmission non-uniformes Type de document : texte imprimé Auteurs : Larbi Benkhaoua, Auteur ; Mohamed-Taoufik Benhabiles, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2016 Importance : 96 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : équations des télégraphistes lignes de transmissions non-uniformes méthodes d’interpolation de point méthodes sans maillage modélisation Telegrapher’s Equations Nonuniform Transmission Lines Point
Interpolation Methods Meshless Methods modeling معادلات خطوط النقل خطوط النقل الكهربائية الغير موحدة طرق الحساب بدون شبكة النمذجةIndex. décimale : 621 Electronique Résumé : With the development of telecommunications and the need for miniaturizing microwave circuits and components, the uniform transmission lines were replaced by non uniform transmission lines (LTNUs) in many applications. With the presence of discontinuities uneasy to model by traditional methods, these lines require powerful technique of design and modeling, especially for arbitrary shapes. In addition, due to the increase in the operation frequencies, it became necessary to predict the transient responses to directly estimate the performances of the microwave circuits over ultra wide frequency bands.
On the other hand, the Meshless methods form a generic group of scientific computing
schemes which was developed since the years 1970s to eliminate the drawbacks of a fixed discretization grid for the approximation of the problem equations.
These methods have the advantages of arbitrary nodal distribution and conformal modeling of R.L.C.G parameters of NUTLs which require less computing costs than the traditional numerical methods.
In this context we implemented the MATLAB codes for the analysis and the simulation
of arbitrary non-uniform transmission lines in the time domain by three Meshless methods :
the polynomial point interpolation method (PIM), the meshless method based on radial
basis functions (RBF-MLM), and the radial point interpolation method (RPIM).
To illustrate the superiority of these methods, such as the irregular discretiszation and the fast convergence rate, results comparisons for two distinct samples were held between the PIM, the RBF-MLM, the RPIM, the FDTD method, and the wavelet expansion method.
These tests allow us to conclude that the RPIM converges quickly and provides the best
compromise between the accuracy and the computing time.Diplôme : Doctorat En ligne : ../theses/electronique/BEN6874.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10190 Contribution à l’élaboration d’un modèle electromagnétique de supports de transmission non-uniformes [texte imprimé] / Larbi Benkhaoua, Auteur ; Mohamed-Taoufik Benhabiles, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2016 . - 96 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : équations des télégraphistes lignes de transmissions non-uniformes méthodes d’interpolation de point méthodes sans maillage modélisation Telegrapher’s Equations Nonuniform Transmission Lines Point
Interpolation Methods Meshless Methods modeling معادلات خطوط النقل خطوط النقل الكهربائية الغير موحدة طرق الحساب بدون شبكة النمذجةIndex. décimale : 621 Electronique Résumé : With the development of telecommunications and the need for miniaturizing microwave circuits and components, the uniform transmission lines were replaced by non uniform transmission lines (LTNUs) in many applications. With the presence of discontinuities uneasy to model by traditional methods, these lines require powerful technique of design and modeling, especially for arbitrary shapes. In addition, due to the increase in the operation frequencies, it became necessary to predict the transient responses to directly estimate the performances of the microwave circuits over ultra wide frequency bands.
On the other hand, the Meshless methods form a generic group of scientific computing
schemes which was developed since the years 1970s to eliminate the drawbacks of a fixed discretization grid for the approximation of the problem equations.
These methods have the advantages of arbitrary nodal distribution and conformal modeling of R.L.C.G parameters of NUTLs which require less computing costs than the traditional numerical methods.
In this context we implemented the MATLAB codes for the analysis and the simulation
of arbitrary non-uniform transmission lines in the time domain by three Meshless methods :
the polynomial point interpolation method (PIM), the meshless method based on radial
basis functions (RBF-MLM), and the radial point interpolation method (RPIM).
To illustrate the superiority of these methods, such as the irregular discretiszation and the fast convergence rate, results comparisons for two distinct samples were held between the PIM, the RBF-MLM, the RPIM, the FDTD method, and the wavelet expansion method.
These tests allow us to conclude that the RPIM converges quickly and provides the best
compromise between the accuracy and the computing time.Diplôme : Doctorat En ligne : ../theses/electronique/BEN6874.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10190 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/6874 BEN/6874 Thèse Bibliothèque principale Thèses Disponible
