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Optimisation d'une centrale solaire intégrée à cycle combiné turbine à vapeur-turbine à gaz. / Mohammed Boumedjirek
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Titre : Optimisation d'une centrale solaire intégrée à cycle combiné turbine à vapeur-turbine à gaz. Type de document : texte imprimé Auteurs : Mohammed Boumedjirek, Auteur ; Abderrezak Merabet, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 118 f. Format : 30 cm. Note générale : Doctorat 3éme CYCLE LMD.
2 copies imprimées disponiblesLangues : Français (fre) Catégories : Français - Anglais
Génie MécaniqueTags : G. Mécanique: Génie Thermique et Énergétique combiné énergie génération hybride solaire performance combined energy generation hybrid solar مجتمعة الطاقة توليد هجين الطاقة الشمسية الأداء Index. décimale : 620 Génie Mécanique Résumé : Solar energy in combined cycle power plants are becoming important as an efficient option among conventional thermal power plants. Nowadays, a great amount of combined cycle gas turbine power plants have been installed and some of them have been working for an appreciable period of time. Work with solar energy it is enough to present some notion about solar radiation as well as the methods and mechanism of system integration were studied. Parabolic trough power plants have been developed in the integrated solar combined cycle system (ISCCS) and the direct steam generation (DSG), each concept has their configuration due to solar energy combination .The technology for the Solar Aided Power Generation (SAPG) is appeared for optimizing this combination in solar contribution to cycle efficiency The target of this work is to evaluate the thermodynamic performance on solar hybrid power plants system for ISCCS and DSG concepts in comparison for a solar to electricity efficiency. However the previous studies have only been based on solar contribution for the ISCCS concept. A 150 [MW] ISCCS power plant operational actually in Hassi R’male in south Algeria is selected as the case study compared to DSG concepts technology. Furthermore the Solar Aided Power Generation is proposed in new DSG concept to assuming the solar contribution with evaluation method, for to calculate the generation share of the solar power system in each concept. The study shows that the DSG concept is the best hybrid system to solar-electric efficiency .Further results obtained indicate that solar contribution increase to the DSG concept proposed on TRNSYS software , in the best extraction of solar thermal for to preheat the feed water heater. The economic study shows the performance in these concepts and shows the lower Levelized energy cost (LEC). The performance of the SAPG in new DSG concept, estimate the effect of the solar collector area in each concept for annual solar thermal energy.
Note de contenu : Annexes. Diplôme : Doctorat En ligne : ../theses/gmecanique/BOU7498.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11330 Optimisation d'une centrale solaire intégrée à cycle combiné turbine à vapeur-turbine à gaz. [texte imprimé] / Mohammed Boumedjirek, Auteur ; Abderrezak Merabet, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2019 . - 118 f. ; 30 cm.
Doctorat 3éme CYCLE LMD.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Génie MécaniqueTags : G. Mécanique: Génie Thermique et Énergétique combiné énergie génération hybride solaire performance combined energy generation hybrid solar مجتمعة الطاقة توليد هجين الطاقة الشمسية الأداء Index. décimale : 620 Génie Mécanique Résumé : Solar energy in combined cycle power plants are becoming important as an efficient option among conventional thermal power plants. Nowadays, a great amount of combined cycle gas turbine power plants have been installed and some of them have been working for an appreciable period of time. Work with solar energy it is enough to present some notion about solar radiation as well as the methods and mechanism of system integration were studied. Parabolic trough power plants have been developed in the integrated solar combined cycle system (ISCCS) and the direct steam generation (DSG), each concept has their configuration due to solar energy combination .The technology for the Solar Aided Power Generation (SAPG) is appeared for optimizing this combination in solar contribution to cycle efficiency The target of this work is to evaluate the thermodynamic performance on solar hybrid power plants system for ISCCS and DSG concepts in comparison for a solar to electricity efficiency. However the previous studies have only been based on solar contribution for the ISCCS concept. A 150 [MW] ISCCS power plant operational actually in Hassi R’male in south Algeria is selected as the case study compared to DSG concepts technology. Furthermore the Solar Aided Power Generation is proposed in new DSG concept to assuming the solar contribution with evaluation method, for to calculate the generation share of the solar power system in each concept. The study shows that the DSG concept is the best hybrid system to solar-electric efficiency .Further results obtained indicate that solar contribution increase to the DSG concept proposed on TRNSYS software , in the best extraction of solar thermal for to preheat the feed water heater. The economic study shows the performance in these concepts and shows the lower Levelized energy cost (LEC). The performance of the SAPG in new DSG concept, estimate the effect of the solar collector area in each concept for annual solar thermal energy.
Note de contenu : Annexes. Diplôme : Doctorat En ligne : ../theses/gmecanique/BOU7498.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11330 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/7498 BOU/7498 Thèse Bibliothèque principale Thèses Disponible Techniques de détection de l’activité vocale dans un canal de communication / Charaf Eddine Chelloug
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Titre : Techniques de détection de l’activité vocale dans un canal de communication : Comparaison aux standards de compression audio. Type de document : texte imprimé Auteurs : Charaf Eddine Chelloug, Auteur ; Atef Farrouki, Directeur de thèse Mention d'édition : 16/06/2020 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2020 Importance : 89 f. Format : 30 cm. Note générale : Doctorat 3éme CYCLE LMD.
1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : Electronique: Signaux et Systèmes de Télécommunications détection d'activité vocale DAV énergie seuil adaptatif Voice Activity Detection Energy Adaptatif threshold تحديد النشاط الصوتي الطاقة عتبة ديناميكية Index. décimale : 621 Electronique Résumé : The main goal of the Voice Activity Detection (VAD) techniques is to distinguish between voiced regions and silent intervals in an audio communication. This step is crucial in most speech processing systems such as mobile communications, Voice over IP, speech recognition and hearing aid systems. This task seems to be relatively easy in a weakly disturbed environment. However, in the case of strongly noise, it becomes difficult to provide accurate information about the presence of active voice. In general, a VAD achieves the compression
of silence intervals in modern communications systems by reducing the average bit rate via the discontinuous transmission mode (DTX). In this thesis, we describe the main standardized VAD methods mentioned in the literature; namely the VAD G.729-B approved by ITU-T in 1996, the AMR VAD (Adaptive Multi Rate), the AFE VAD (Advanced front-end) and SILK (developed by Skype). The VAD of the G.729-B standard generates a binary VAD decision for each frame as a function of four relevant parameters extracted from the audio signal. In a simplified way, these parameters are directly related to energy and spectral components of a voiced frame.
The G.729-B is used in the majority of audio transmission applications, becoming the most popular VAD technique. Therefore, the G-729-B is today the best standard for comparative studies in most scientific articles dealing with VAD. In the 1st contribution, we propose a VAD scheme based on adaptive threshold while
maintaining the False Acceptance Rate at a nominal value. As well known in the binary decision theory, the error rate, denoted ""False Acceptance Rate"", is related to the probability of misclassified a frame of silence as Active Voice. The basic idea is to perform sequential tests, based on full band energy, in order to reject or to accept the frame under investigation as active voice region. The most interesting feature of the proposed algorithm concerns its ability to dynamically update the noise level estimator, according to the current environment. Taking into account the long-term stationary property of the speech, we also developed a
smoothing procedure to discard discontinuities that may appear in the processed signal. The performance of the proposed approach has been evaluated and compared to the VAD of
the G.729-B in several situations including various environmental acoustic noises with
different SNRs. Analysis of the results has been performed using the NOIZEUS experimental
database as well as real recorded signals.The 2nd contribution consists of implementing the proposed approach on a microcontrollerbased system, in order to:
• Ensure the robustness of the algorithm,
• Evaluate its implementation complexity
• Validate the real time operation mode
In this context, various tests were conducted in real time mode via the development tools
available on the microcontroller system (STM32F7). These tools allowed performing realtime monitoring of several signal parameters in realistic situations. By this way, we were able to accurately determine the processing time (Latency) required to generate a final decision for each frame. The real-time analysis allowed us to obtain a global latency of 4 μs, which seems sufficient to guarantee real-time operation regarding to the common sampling frequencies of speech processing systems (8 kHz to 16 kHz).
Diplôme : Doctorat En ligne : ../theses/electronique/CHE7760.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11593 Techniques de détection de l’activité vocale dans un canal de communication : Comparaison aux standards de compression audio. [texte imprimé] / Charaf Eddine Chelloug, Auteur ; Atef Farrouki, Directeur de thèse . - 16/06/2020 . - جامعة الإخوة منتوري قسنطينة, 2020 . - 89 f. ; 30 cm.
Doctorat 3éme CYCLE LMD.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : Electronique: Signaux et Systèmes de Télécommunications détection d'activité vocale DAV énergie seuil adaptatif Voice Activity Detection Energy Adaptatif threshold تحديد النشاط الصوتي الطاقة عتبة ديناميكية Index. décimale : 621 Electronique Résumé : The main goal of the Voice Activity Detection (VAD) techniques is to distinguish between voiced regions and silent intervals in an audio communication. This step is crucial in most speech processing systems such as mobile communications, Voice over IP, speech recognition and hearing aid systems. This task seems to be relatively easy in a weakly disturbed environment. However, in the case of strongly noise, it becomes difficult to provide accurate information about the presence of active voice. In general, a VAD achieves the compression
of silence intervals in modern communications systems by reducing the average bit rate via the discontinuous transmission mode (DTX). In this thesis, we describe the main standardized VAD methods mentioned in the literature; namely the VAD G.729-B approved by ITU-T in 1996, the AMR VAD (Adaptive Multi Rate), the AFE VAD (Advanced front-end) and SILK (developed by Skype). The VAD of the G.729-B standard generates a binary VAD decision for each frame as a function of four relevant parameters extracted from the audio signal. In a simplified way, these parameters are directly related to energy and spectral components of a voiced frame.
The G.729-B is used in the majority of audio transmission applications, becoming the most popular VAD technique. Therefore, the G-729-B is today the best standard for comparative studies in most scientific articles dealing with VAD. In the 1st contribution, we propose a VAD scheme based on adaptive threshold while
maintaining the False Acceptance Rate at a nominal value. As well known in the binary decision theory, the error rate, denoted ""False Acceptance Rate"", is related to the probability of misclassified a frame of silence as Active Voice. The basic idea is to perform sequential tests, based on full band energy, in order to reject or to accept the frame under investigation as active voice region. The most interesting feature of the proposed algorithm concerns its ability to dynamically update the noise level estimator, according to the current environment. Taking into account the long-term stationary property of the speech, we also developed a
smoothing procedure to discard discontinuities that may appear in the processed signal. The performance of the proposed approach has been evaluated and compared to the VAD of
the G.729-B in several situations including various environmental acoustic noises with
different SNRs. Analysis of the results has been performed using the NOIZEUS experimental
database as well as real recorded signals.The 2nd contribution consists of implementing the proposed approach on a microcontrollerbased system, in order to:
• Ensure the robustness of the algorithm,
• Evaluate its implementation complexity
• Validate the real time operation mode
In this context, various tests were conducted in real time mode via the development tools
available on the microcontroller system (STM32F7). These tools allowed performing realtime monitoring of several signal parameters in realistic situations. By this way, we were able to accurately determine the processing time (Latency) required to generate a final decision for each frame. The real-time analysis allowed us to obtain a global latency of 4 μs, which seems sufficient to guarantee real-time operation regarding to the common sampling frequencies of speech processing systems (8 kHz to 16 kHz).
Diplôme : Doctorat En ligne : ../theses/electronique/CHE7760.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11593 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité CHE/7760 CHE/7760 Thèse Bibliothèque principale Thèses Disponible
Titre : الضمانات القانونية لإستخدام الطاقة النونية لأغراض سلمية Type de document : texte imprimé Auteurs : توفيق قوميدي, Auteur ; محمد زغداوي, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2013 Importance : 182 ورقة. Format : 30 سم Note générale : 2نسخ موجودة مكتبة المركزية
Langues : Arabe (ara) Catégories : Arabe
القانونTags : طاقة نووية سلمية ضمانات Energie Nucléaire Pacifique Garanties Energy Nuclear Pacific Guarantees Index. décimale : 340 القانون Résumé :
Nuclear Energy is one of the most important discoveries during the twentieth century. This energy is causing debates about its multiple uses. It has benefits leading to development and progress and besides has its black side menacing humanity.
These two sides are opposite but they determine the aim of the nuclear energy use. In order to avoid the bad usage of this energy and deviate from its pacific way, and for that reason, international community has employed considerable efforts.
This lead to request the following problematic:
How have international efforts succeed to regularize legal guarantees to minimize harmful nuclear propagation?
Considering which has been exposed by this study concerning the most important benefits of nuclear energy in different fields then present the wrongdoings resulting from its use.
This study speaks also about international efforts among bilateral, territorial and national levels for limiting nuclear use invasion however it encourages its pacific use.
Finally, the study leant on the most important systems of guarantee related to the pacific use of nuclear energy referring to international documents. In addition, it approached the most important systems of security and insurance relating to nuclear energy.Diplôme : Magistère En ligne : ../theses/droit/AGUO4005.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=9591 الضمانات القانونية لإستخدام الطاقة النونية لأغراض سلمية [texte imprimé] / توفيق قوميدي, Auteur ; محمد زغداوي, Directeur de thèse . - constantine [Algérie] : Université Constantine 1, 2013 . - 182 ورقة. ; 30 سم.
2نسخ موجودة مكتبة المركزية
Langues : Arabe (ara)
Catégories : Arabe
القانونTags : طاقة نووية سلمية ضمانات Energie Nucléaire Pacifique Garanties Energy Nuclear Pacific Guarantees Index. décimale : 340 القانون Résumé :
Nuclear Energy is one of the most important discoveries during the twentieth century. This energy is causing debates about its multiple uses. It has benefits leading to development and progress and besides has its black side menacing humanity.
These two sides are opposite but they determine the aim of the nuclear energy use. In order to avoid the bad usage of this energy and deviate from its pacific way, and for that reason, international community has employed considerable efforts.
This lead to request the following problematic:
How have international efforts succeed to regularize legal guarantees to minimize harmful nuclear propagation?
Considering which has been exposed by this study concerning the most important benefits of nuclear energy in different fields then present the wrongdoings resulting from its use.
This study speaks also about international efforts among bilateral, territorial and national levels for limiting nuclear use invasion however it encourages its pacific use.
Finally, the study leant on the most important systems of guarantee related to the pacific use of nuclear energy referring to international documents. In addition, it approached the most important systems of security and insurance relating to nuclear energy.Diplôme : Magistère En ligne : ../theses/droit/AGUO4005.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=9591 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité قوم/4005 قوم/4005 Thèse Bibliothèque principale Thèses Disponible Documents numériques
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