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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Diffraction studies of structure and growth of films absorbed on the AG(111) surface

Wu, Zhongming, January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 197-202). Also available on the Internet.
232

Optimized SIMD scheduling and architecture implementation for ultra-low energy bioimaging processor / Βελτιστοποιημένος χρονοπρογραμματισμός εντολών για παράλληλη επεξεργασία (SIMD) και υλοποίηση αρχιτεκτονικής για επεξεργαστή χαμηλής κατανάλωσης για αλγόριθμους βιοαπεικόνισης

Ψύχου, Γεωργία 03 August 2010 (has links)
On-line poultry monitoring can significantly improve living conditions of hens in industrial farms. A very low-cost low-energy solution needs to be provided though. ASIPs can be an ideal solution when they cover many submarkets and low-energy concepts are used for their realization. Aiming to high energy-efficiency, this work implements data parallelization, using a recently introduced software-controled SIMD realization in an innovative way. A manual mapping and scheduling effort of the most crucial part of the application leads to a highly optimized result, in terms of cycles, area and energy. This manual scheduling implementation must also be supported by a commercial compiler tool so that the design-time is minimized. Moreover, energy-efficient mapping must be explored for the remaining parts of the code. In that case, because the frequency of occurence of a part of the code is very low, more attention should be given to minimizing the area overhead. Increasing the energy efficiency of the data-path in such ways can be very important, since data- path can be dominant in the total energy-pie, once the instruction/data memory overhead is minimized by other complementary approaches. / Η αυτόματη μέθοδος παρακολούθησης ζωντανών οργανισμών μπορεί να βελτιώσει σημαντικά τις συνθήκες διαβίωσης των ζώων στις βιομηχανικές φάρμες. Για να είναι οικονομικά εφικτή όμως μια τέτοια λύση πρέπει να είναι μια λύση χαμηλής ενέργειας. Τα ASIPs μπορούν να είναι μια ιδανική λύση όταν τεχνικές χαμηλής κατανάλωσης ενέργειας εφαρμόζονται σε αυτά, καθώς λόγω της ευελιξίας τους μπορούν να καλύπτουν πολλούς τομείς της συγκεκριμένης αγοράς. Στοχεύοντας σε υψηλή εξοικονόμηση ενέργειας, η παρούσα δουλειά υλοποιεί παραλληλισμό δεδομένων, χρησιμοποιώντας μια προσφάτως προταθείσα πραγματοποίηση Single Instruction Multiple Data (SIMD) εντολών, που υλοποιούνται μέσω software με ένα καινοτόμο τρόπο. Μια χειρωνακτική προσπάθεια αντιστοίχισης σε υλικό του πιο κρίσιμου κομματιού της εφαρμογής και χρονοπρογραμματισμού των εντολών του οδηγεί σε ένα πολύ βελτιστοποιημένο αποτέλεσμα αναφορικά με τους κύκλους εκτέλεσης, την καταλαμβανόμενη επιφάνεια και την απαιτούμενη ενέργεια. Η χειρωνακτική υλοποίηση χρονοπρογραμματισμού των εντολών πρέπει να μπορεί να επιτευχθεί από ένα εμπορικό εργαλείο μετάφρασης (compiler tool) ώστε στο μέλλον ο χρόνος σχεδιασμού να ελαχιστοποιηθεί. Επιπλέον, πρέπει να διερευνηθεί μια αποδοτική ως προς το θέμα της ενέργειας προσπάθεια απεικόνισης σε υλικό για τα υπόλοιπα τμήματα της εφαρμογής πέραν του πιο κρίσιμου. Σε αυτή την περίπτωση, επειδή η συχνότητα εμφάνισης αυτών των τμημάτων του κώδικα είναι πολύ μικρή, έμφαση δίνεται στην ελαχιστοποίηση της επιφάνειας του υλικού. Η βελτίωση της κατανάλωσης ενέργειας του data-path με τέτοιους τρόπους είναι πολύ σημαντική, αφού το data-path είναι κυρίαρχο στην κατανομή της ενέργειας, όταν η επιβάρυνση της μνήμης δεδομένων και εντολών ελαχιστοποιείται από συμπληρωματικές μεθόδους, όπως συμβαίνει στο προτεινόμενο ASIP.
233

Optimized SIMD architecture exploration and implementation for ultra-low energy processors / Εξερεύνηση και υλοποίηση βελτιστοποιημένης SIMD αρχιτεκτονικής για επεξεργαστές πολύ χαμηλής κατανάλωσης

Δακουρού, Στεφανία 19 July 2012 (has links)
On-line monitoring is an important challenge in future biotechnology applications, for instance in the domain of precision livestock farming where a strong need is present for low-cost intelligent sensors to monitor animal welfare. On-line poultry monitoring can significantly improve living conditions of hens in industrial farms. A very low-cost low-energy solution needs to be provided though due to the stringent battery limitations. Domain-specific ASIPs can be an ideal solution when they cover enough submarkets to increase the production volume (reducing the price) and ultra-low energy concepts are used for their realization. This work is a part of a larger project and aiming to high energy-efficiency. The current study implements data parallelization, using a recently introduced software-controlled SIMD realization in an innovative way. The approaches that have been employed for the determination of the final instruction set of the architecture that has been created for the mapping of the critical Gauss loop of the detection application, are thoroughly explored. The re-design of the data-parallel data path, also referred to as Soft-SIMD architecture, has been necessary in order to achieve instruction encoding optimization. Furthermore, we have explored the capabilities that a commercial compiler retargetable Tool, like Target, can offer for our target design and we have suggested some potential modifications that would help the tool to become more efficient and useful for a designer’s needs in such architecture. Thereby, this study also demonstrates the promising results obtained by experimenting with detours around the current Target tool design limitations. Finding the right balance between efficiency and flexibility requires the ability to quickly evaluate alternative architectures through simulations and testing techniques. The methods developed for exactly this purpose, with the help of Target’s IP Designer retargetable tool-suite, are discussed in detail. By exploiting the profiling information produced by the ISS, and by reading the assembly code produced by the C compiler, it is possible to identify the instructions in the critical loop, and optimize them by using a number of techniques discussed. The main purpose of this optimization is to reduce the cycle count of the application, in order to reduce the overall power consumption. VHDL files of the optimized and un-optimized processor are automatically generated using the HDL generation tool. However, examining a bio-imaging application, instantiated from the ULP-ASIP architectural template [FEENECS book], many other issues are present too. In particular, the way that these kinds of implementations have to be tested should be taken into consideration. Preferably, the testability has not only to be sufficient and efficient but also reusable, in the sense that test patterns should be able to be generated not only for a specific application or for a group of applications but for the entire architectural template. Therefore, this study also illustrates a Systematic Test Vector generation process for the ULP-ASIP template. Our goal is to make generalized principles, because such principles are reusable and can be applied to any instances, such as our present processor for the Gauss Filter. Finally, this study is completed by presenting some realistic power numbers based on layout back-annotation, which concern the data path components of the processor. Based on all the advanced optimizations and broad search space explorations that are presented in this thesis, a heavily optimized ASIP architecture has been fully implemented which results in a low-cost ultra low-energy consumption while still meeting all the performance requirements. / Η αυτόματη μέθοδος παρακολούθησης ζωντανών οργανισμών, όπως έχει ερευνηθεί και δημοσιευθεί από το Τμήμα Biosystems (BIOSYST) του K.U. Leuven [1], συνίσταται από μια εϕαρμογή με «υπολογιστική όραση», η οποία, βασιζόμενη στις αποκρίσεις τους, κατηγοριοποιεί τη συμπεριϕορά τους. Η βιοτεχνολογική αυτή εϕαρμογή αναπτύσσει ένα πλήρως αυτοματοποιημένο σύστημα «υπολογιστικής όρασης» σε μεμονωμένες και υπό περιορισμό όρνι- θες.Η εϕαρμογή χωρίζεται σε δύο αλγόριθμους, εκ των οποίων ο πρώτος ανιχνεύει το αντι- κείμενο παρακολούθησης (detection algorithm) και ο δεύτερος το εντοπίζει (tracking algorithm). Η παρούσα μελέτη αποτελεί κομμάτι ενός μεγαλυτέρου project και συνέχεια της προηγούμενης δουλείας που αναπτύχθηκε στον τομέα αυτό.Ο σκοπός αυτής της μελέτης είναι η εξερεύνηση της αρχιτεκτονικής που έχει δημιουργηθεί για την αντιστοίχιση του κρίσιμου βρόχου Gauss του αλγόριθμου ανίχνευσης προκειμένου να καθοριστεί το τελικό σύνολο εντολών του ULP-ASIP SIMD επεξεργαστή. Οι τεχνικές και οι προσεγγίσεις που χρησιμοποιούνται για την υποστήριξη της διαδικασίας βελτιστοποίησης της κωδικοποίησης του συνόλου εντολών παρουσιάζονται εκτεταμένα στο κεϕάλαιο 2. Επιπλέον, κατά τη διάρκεια της εξερεύνησης της αρχιτεκτονικής, το σύνολο εντολών που ορίστηκε και οι τεχνικές αντιστοίχισης επανεξετάζονται, προκειμένου να μειωθεί το συνολικό κόστος εκτέλεσης. Η εύρεση της σωστής ισορροπίας μεταξύ της αποτελεσματικότητας και της ευελιξίας απαιτεί την ικανότητα να αξιολογούνται γρήγορα εναλλακτικές αρχιτεκτονικές μέσω εξομοιώσεων και τεχνικών δοκιμών. Το Κεϕάλαιο 3 επεξηγεί τις μεθόδους που αναπτύχθηκαν ακριβώς για το σκοπό αυτό, με τη βοήθεια του περιβάλλοντος σχεδίασης IP των TARGET Compiler Τεχνολογιών η οποία προσϕέρει ένα πλήρες reTARGETable εργαλείο. Ωστόσο, μια πιο συστηματική διαδικασία παραγωγής διανυσμάτων δοκιμής για ολόκληρη την πλατϕόρμα ULP-ASIP κατέληξε να είναι ένα πολύ σημαντικό πλεονέκτημα για την επικύρωση της λειτουργίας του επεξεργαστή ULP-ASIP. Ως εκ τούτου, μια τέτοια μέθοδος, αναλύεται και παρουσιάζεται εκτεταμένα στο κεϕάλαιο 4. Τέλος, το Κεϕάλαιο 5 παρουσιάζει την εκτίμηση της ενέργειας του data path του επεξεργαστή. Με βάση όλες τις προηγμένες βελτιστοποιήσεις και τις ευρείες εξερευνήσεις του χώρου αναζήτησης που παρουσιάζονται στα προηγούμενα κεϕάλαια, μια ισχυρά βελτιστοποιημένη συνθέσιμη αρχιτεκτονική ASIP υλοποιείται πλήρως η οποία οδηγεί σε μια χαμηλού κόστους, πολύ χαμηλής κατανάλωσης ενέργειας πλατϕόρμα, καλύπτοντας συγχρόνως όλες τις απαιτήσεις επιδόσεων.
234

Energy efficient instruction decoding in application: Specific instruction - set processors / Αποκωδικοποίηση εντολών για χαμηλή κατανάλωση ενέργειας σε επεξεργαστές συνόλου εντολών ειδικού σκοπού

Κάργας, Χρήστος 04 September 2013 (has links)
With commercial processor design tools, a designer can quickly design a C- programmable ASIP for a specific application domain. There are several such ASIPs available for both wireless (UWB baseband processing), encryption, and biomedical processing (particularly for ECG beat detection). In traditional CPUs and DSPs the impact of the instruction-set definition and the complexity of the instruction decoder can be substantial, especially in terms of power consumption. Fully orthogonal VLIW processors, do not incur the cost of an instruction decoder that severely. Instead the instruction word becomes very large, thereby shifting the (power-)cost to the program memory or instruction cache. For the purposes of this thesis a SIMD processor is developed and is compared to a soft-SIMD to observe its area, performance and energy efficiency for a bioimaging benchmark and how the processor description in the ASIP language nML, defines the generated HDL. This SIMD processor is turned into orthogonal and using iterative experiments it is investigated, what is the impact on power while manipulating the instruction-set architecture in combination with the program memory size. It is also investigated how instruction-set re-configuration can be exploited to improve power efficiency. Using this investigation guidelines for low-power ASIP design can be produced. / Με τη σύγχρονη τεχνολογία σχεδιασμού επεξεργαστών, ο σχεδιαστής μπορεί με ευκολία να σχεδιάσει ένα προγραμματιζόμενο Επεξεργαστή Συνόλου Εντολών Ειδικού Σκοπού (ASIP - Application-Specific Instruction-set Processor) για ένα συγκεκριμένο εύρος εφαρμογών. Υπάρχουν διάφοροι τέτοιοι επεξεργαστές διαθέσιμοι για ασύρματες εφαρμογές, κρυπτογράφηση και βιοϊατρικές εφαρμογές (π.χ. στον αλγόριθμο εντοπισμού χτύπου ηλεκτροκαρδιογραφήματος). Στους παραδοσιακούς επεξεργαστές και επεξεργαστές σήματος (DSP - Digital Signal Processor) ο ορισμός του συνόλου εντολών και η πολυπλοκότητα έχουν μεγάλη επίδραση, ειδικά στην κατανάλωση ισχύος. Μία πιθανή λύση σε αυτό το πρόβλημα είναι οι ορθογώνιοι επεξεργαστές μεγάλου μεγέθους λέξης εντολής (VLIW - Very Large Instruction Word). Με τον όρο ορθογώνιο επεξεργαστή, ορίζεται ένας επεξεργαστής οριζόντιου σύνολου εντολών, άρα ένας επεξεργαστής στον οποίο μπορεί να υπάρξει κάθε διαθέσιμος συνδυασμός μεταξύ των διαθέσιμων εντολών και των μεθόδων διευθυνσιοδότησης για πρόσβαση στη μνήμη και το αρχείο καταχωρητών. Οι ορθογώνιοι επεξεργαστές δεν επιβαρύνουν τόσο τον αποκωδικοποιητή εντολών. Αντί αυτού το μέγεθος της λέξης της εντολής γίνεται πολύ μεγάλο, και έτσι μετατίθεται το ενεργειακό κόστος στην μνήμη εντολών προγράμματος (program memory )ή την κρυφή μνήμη εντολών προγράμματος (instruction cache). Για τους σκοπούς αυτής της διπλωματικής εργασίας, αναπτύχθηκε ένας επεξεργαστής SIMD, ο οποίος συγκρίνεται με έναν soft-SIMD για να μελετηθούν η απαιτούμενη περιοχή στο ενσωματωμένο, επιδόσεις και κατανάλωση ενέργειας για μία βιοϊατρική εφαρμογή, καθώς και το πως η περιγραφή ενός επεξεργαστή στη γλώσσα περιγραφής επεξεργαστών ASIP nML ορίζει την παραγούμενη γλώσσα περιγραφής υλικού (HDL - Hardware Description Language). Ο επεξεργαστής αυτός μετατρέπεται σε ορθογώνιο, και με τη χρήση επαναληπτικών πειραμάτων μελετάται η επίδραση στην κατανάλωση ενέργειας κατά τη διάρκεια αλλαγών στην αρχιτεκτονική του συνόλου εντολών και του μεγέθους της μνήμης εντολών προγράμματος. Ακόμη μελετάται πως μπορεί να εκμεταλλευτεί ο σχεδιαστής την αναδιάρθρωση του συνόλου εντολών για να βελτιώσει την κατανάλωση ενέργειας.
235

Desempenho lumínico em edificação escolar com estratégias sustentáveis e bioclimáticas : um estudo de caso

Krum, Christiane Cunha January 2011 (has links)
Frente ao desenfreado desenvolvimento da sociedade nas suas diversas esferas, busca-se novas maneiras de habitar o planeta, de forma a preservá-lo para as futuras gerações. Uma das vertentes nas quais o homem pode intervir e, assim, ajudar a preservar os recursos naturais do planeta, diz respeito à busca por economia energética. Em edificações de uso prolongado e onde são desenvolvidas atividades visuais intensas, o uso da luz natural é de extrema valia, não apenas resultando em economia de energia elétrica, mas também contribuindo para o conforto ambiental e bem estar de seus usuários através dos benefícios proporcionados por esta luz. Portanto, o uso da luz natural sendo complementada pela luz artificial é de profunda importância para o bom desempenho lumínico da edificação. Fruto dos trabalhos desenvolvidos pelo grupo de pesquisa em Edificações e Comunidades Sustentáveis do NORIE/UFRGS, a edificação escolar analisada nesta pesquisa foi projetada a partir de estratégias sustentáveis e bioclimáticas. Esta pesquisa tem como objetivo avaliar o desempenho lumínico de uma sala de aula da edificação supracitada, para, assim, proporcionar considerações acerca das decisões projetuais tomadas. A metodologia utilizada para a obtenção destas informações consistiu na análise das intenções projetuais dos autores da edificação, no levantamento das características físicas e construtivas da escola e em medições lumínicas realizadas ao longo de um dia, em datas próximas aos solstícios e equinócios, no interior e no exterior da edificação. E, para verificar a eficiência de alguns elementos da edificação e propor melhorias de forma a incrementar o seu desempenho lumínico, foram realizadas simulações da sala de aula. A partir dos resultados gerados nesta pesquisa pretende-se não apenas fornecer informações sobre o desempenho lumínico desta edificação, como levantar questões que poderão embasar futuros projetos preocupados em fazer um melhor uso desta fonte natural, gratuita e de qualidade: a luz natural. / New manners on how to inhabit the planet are sought due to the increasing society development, in order to preserve it for the future generation. The seeking for low-energy consumption alternatives is one of the key issues the man can intervene in order to preserve earth´s natural resources. The usage of natural light is extremely valuable in edifications where intensive visual activities are developed; not only resulting in electric energy savings but also contributing for the environmental comfort and users´ well-being through the benefits provided by this light. Hence, the natural light usage complemented by the artificial light has a great importance in the edification´s luminous performance. The scholar edification analyzed by this research was projected with sustainable and bioclimatic strategies, based on information developed by NORIE/UFRGS research group on Sustainable Edifications and Communities. This research’s objective is to evaluate the luminous performance of one of the scholar edification´s classroom in order to provide considerations in relation to the project´s decisions. The selected methodology for these information gathering was based on the edification authors´ project intensions, the physical and constructive school´s characteristics, and the luminous measurements taken along a hole day. These measurements were taken on dates close to solstices and equinoxes, in the edification´s interior and exterior. Classroom model simulations were developed in order to verify some building´s elements efficiency and to propose improvements for its luminous performance. The research´s results intends to provide relevant information about this particular edification´s luminous performance; and also to rise useful knowledge for future projects regarding daylight usage, a free and natural source of energy.
236

Analyse de la fiabilité des outils de simulation et des incertitudes de métrologie appliquée à l'efficacité énergétique des bâtiments / Analysis of simulation tools reliability and measurement uncertainties for Energy Efiiciency in Buildings

Spitz, Clara 09 March 2012 (has links)
Le recours à la simulation est décisif dans le processus de conception d'un bâtiment neuf. Elle permet d'évaluer différentes alternatives au regard de la performance énergétique et du confort des occupants et constitue ainsi un outil d'aide à la décision incontournable. Aujourd'hui la question de la fiabilité des codes de simulation n'est pas à négliger. L'augmentation des performances énergétiques des bâtiments, pourrait mettre en défaut un certain nombre d'hypothèses de modélisation généralement admises pour les bâtiments standards du fait de la prépondérance nouvelle de phénomènes physiques jusqu'alors négligés ou mal pris en compte. Dans le même temps on s'intéresse de plus en plus à la garantie de performance qui consiste à vérifier que les performances énergétiques réelles sont bien en adéquation avec les objectifs fixés lors de la conception or il est souvent constaté des erreurs entre consommation mesurée et estimée compte tenu des incertitudes liées notamment à la mise œuvre, aux occupants et aux conditions météorologiques. L'augmentation des exigences de précision des calculs qui en résulte rend essentiel d'apprécier les incertitudes associées à ces prévisions afin d'améliorer le processus de construction et d'évaluation. Les travaux de cette thèse portent en particulier sur l'évaluation et la hiérarchisation des incertitudes sur les résultats des simulations en phase de conception. Une méthodologie a été développée basée en trois temps qui permet d'identifier les paramètres de conception les plus influents sur la performance énergétique d'un bâtiment et de rendre compte des effets de l'incertitude associée à ces paramètres sur cette même performance. La première étape consiste à identifier parmi l'ensemble des paramètres du modèle ceux qui ont une influence sur le résultat qui nous intéresse. Celle-ci est assurée au moyen d'une analyse de sensibilité locale du modèle. La deuxième étape consiste à évaluer les incertitudes associées à ces paramètres les plus influents afin de propager cette incertitude dans le code de calcul et évaluer l'incertitude sur le résultat. Cette étape est effectuée au moyen d'approches probabilistes de type Monte Carlo. Nous ajoutons une troisième étape de manière à évaluer la responsabilité de chacun des paramètres sur les incertitudes associées au résultat. Cette information est cruciale pour l'utilisateur. Cette dernière étape est traitée au moyen d'une analyse de sensibilité globale sur un jeu de paramètres réduit. Nous nous sommes appuyés sur la plateforme expérimentale INCAS située à l'INES au Bourget du Lac (73) pour identifier les incertitudes de mesure mais aussi les incertitudes dont les hypothèses de modélisation font l'objet. Cette méthodologie pourra être utilisée durant tout le processus de conception d'un bâtiment, des premières esquisses à son exploitation. En phase de conception, cette méthodologie permettra d'orienter les choix architecturaux en évitant des options dont la fiabilité des résultats est incertaine. En phase d'exploitation, elle permettra d'identifier les points de mesure les plus pertinents, afin de réduire l'incertitude des paramètres les plus influents pour effectuer un diagnostic énergétique plus fiable du bâtiment. Elle pourra aussi s'étendre aux incertitudes liées aux occupants et aux conditions météorologiques. / Nowadays, simulation tools are widely used to design buildings since their energy performance is increasing. Simulation is used to predict building energy performance and to improve thermal comfort of occupants, but also to reduce the environmental impact of the building over its whole life cycle and the cost of construction and operation. Simulation becomes an essential decision support tool, but its reliability should not be ignored. Hypothesis, made 10 years ago for buildings conception, are often not adapted to the new constructions because of physical phenomena which until now were overlooked. At the same time, guarantees of energy efficiency, which aims to check if actual energy performances are matching the conception goals, are becoming important. But there are usually differences between measured and simulation data. They may be the result of mistakes and unknowns on input parameters, on schedule occupation or on weather data. Today it's important to evaluate simulation and measurement reliability and uncertainties to improve design building. This PhD work aimed to evaluate and order simulation results uncertainties during the design building process. A methodology in three steps was developed to determine influential parameters on building energy performance and to identify the influence of these parameters uncertainty on the building performance. The first step uses the local sensitivity analysis and identifies the most influential parameters on the outputs among all parameters. This step enables to reduce the number of parameters which is necessary to proceed the following steps The second step is an uncertainty analysis focuses on quantifying uncertainty in model outputs. This step is conducted with the Monte Carlo probabilistic approach. The last step uses global sensitivity analysis which is the study of how uncertainty in the output of a model can be apportioned to different sources of uncertainty in the model input. This methodology was applied to the INCAS experimental platform of the French National Institute of Solar Energy (INES) in Le-Bourget-du-Lac to identify measure uncertainties and uncertainties on simulation hypothesis. This methodology may be used during the whole building design process, from the first sketches to the operating phase. It will enable to guide the architectural and technical choices and to avoid unstable options with important uncertainty. During the exploitation stage, this methodology will allow to identify the most suitable measurement in order to reduce parameters uncertainties and consequently to get the energy diagnostic more reliable. Moreover this methodology could also be used to determine uncertainties on related to inoccupants and to weather conditions.
237

Desempenho lumínico em edificação escolar com estratégias sustentáveis e bioclimáticas : um estudo de caso

Krum, Christiane Cunha January 2011 (has links)
Frente ao desenfreado desenvolvimento da sociedade nas suas diversas esferas, busca-se novas maneiras de habitar o planeta, de forma a preservá-lo para as futuras gerações. Uma das vertentes nas quais o homem pode intervir e, assim, ajudar a preservar os recursos naturais do planeta, diz respeito à busca por economia energética. Em edificações de uso prolongado e onde são desenvolvidas atividades visuais intensas, o uso da luz natural é de extrema valia, não apenas resultando em economia de energia elétrica, mas também contribuindo para o conforto ambiental e bem estar de seus usuários através dos benefícios proporcionados por esta luz. Portanto, o uso da luz natural sendo complementada pela luz artificial é de profunda importância para o bom desempenho lumínico da edificação. Fruto dos trabalhos desenvolvidos pelo grupo de pesquisa em Edificações e Comunidades Sustentáveis do NORIE/UFRGS, a edificação escolar analisada nesta pesquisa foi projetada a partir de estratégias sustentáveis e bioclimáticas. Esta pesquisa tem como objetivo avaliar o desempenho lumínico de uma sala de aula da edificação supracitada, para, assim, proporcionar considerações acerca das decisões projetuais tomadas. A metodologia utilizada para a obtenção destas informações consistiu na análise das intenções projetuais dos autores da edificação, no levantamento das características físicas e construtivas da escola e em medições lumínicas realizadas ao longo de um dia, em datas próximas aos solstícios e equinócios, no interior e no exterior da edificação. E, para verificar a eficiência de alguns elementos da edificação e propor melhorias de forma a incrementar o seu desempenho lumínico, foram realizadas simulações da sala de aula. A partir dos resultados gerados nesta pesquisa pretende-se não apenas fornecer informações sobre o desempenho lumínico desta edificação, como levantar questões que poderão embasar futuros projetos preocupados em fazer um melhor uso desta fonte natural, gratuita e de qualidade: a luz natural. / New manners on how to inhabit the planet are sought due to the increasing society development, in order to preserve it for the future generation. The seeking for low-energy consumption alternatives is one of the key issues the man can intervene in order to preserve earth´s natural resources. The usage of natural light is extremely valuable in edifications where intensive visual activities are developed; not only resulting in electric energy savings but also contributing for the environmental comfort and users´ well-being through the benefits provided by this light. Hence, the natural light usage complemented by the artificial light has a great importance in the edification´s luminous performance. The scholar edification analyzed by this research was projected with sustainable and bioclimatic strategies, based on information developed by NORIE/UFRGS research group on Sustainable Edifications and Communities. This research’s objective is to evaluate the luminous performance of one of the scholar edification´s classroom in order to provide considerations in relation to the project´s decisions. The selected methodology for these information gathering was based on the edification authors´ project intensions, the physical and constructive school´s characteristics, and the luminous measurements taken along a hole day. These measurements were taken on dates close to solstices and equinoxes, in the edification´s interior and exterior. Classroom model simulations were developed in order to verify some building´s elements efficiency and to propose improvements for its luminous performance. The research´s results intends to provide relevant information about this particular edification´s luminous performance; and also to rise useful knowledge for future projects regarding daylight usage, a free and natural source of energy.
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Nanoemulsões encapsulando quercetina produzidas pelo método do ponto de inversão da emulsão (EIP): estabilidade físico-química e avaliação da atividade antioxidante in vitro e em produto cárneo / Nanoemulsions encapsulating quercetina produced by the emulsion inversion point method (EIP): physicochemical stability and evaluation of in vitro antioxidant activity and after incorporation in meat product

Cynthia de Carli 24 March 2017 (has links)
A quercetina é um flavonoide com alta atividade antioxidante reconhecida. Devido a este fato, a indústria alimentícia tem buscado alternativas para a aplicação deste bioativo como antioxidante em matrizes alimentícias. No entanto, incorporar a quercetina em formulações alimentícias pode ser desafiador, pois sua molécula tem relativo grau de hidrofobicidade. Os métodos de encapsulação em nanoemulsões podem tornar viável a proteção do flavonoide, bem como permitir sua dispersibilidade em meios aquosos . O objetivo do presente trabalho foi produzir nanoemulsões (fase oleosa: óleo de girassol) encapsulando quercetina pelo método do ponto de inversão da emulsão (EIP, emulsion inversion point), determinando parâmetros de operação que viabilizem um futuro escalonamento do processo, e a realização de um estudo de caso sobre a incorporação das nanodispersões em patê de frango. Os parâmetros de produção que foram avaliados foram : tipo e concentração de tensoativo (razão SOR, razão tensoativo:óleo), concentração de óleo, concentração de cosolvente e velocidade de agitação. Foram produzidas nanoemulsões utilizando dois tensoativos diferentes, Tween 80 e Brij 30. As porcentagens de quercetina encapsulada foram 0,15 e 0,30% (m/m). Dentre estas, a concentração de 0,30% foi a mais viável para a aplicação no patê de frango, por apresentar melhor distribuição de tamanho de gotícula (diâmetro hidrodinâmico), não apresentar variação significativa de oxidação lipídica e maior conservação da quercetina encapsulada por um período de 90 dias. Os valores de tensão interfacial obtidos mostram que a quercetina provoca abaixamento da tensão interfacial do sistema, o que pode indicar que a quercetina forma um complexo com os tensoativos utilizados, fato que influencia decisivamente na sua localização nas nanogotas. Das formulações testadas para patê de frango contendo quercetina, apenas a formulação usando quercetina livre não apresentou boa avaliação nos itens cor e sabor. Tal resultado justifica a necessidade da incorporação da quercetina em nanoemulsões para não causar alterações sensoriais no produto. / Quercetin is a flavonoid with recognized high antioxidant activity Due to this fact, the food industry has been trying to use it as an alternative as a preservative in food matrices. However, incorporating quercetin into food formulations may be challenging due to its relative degree of hydrophobicity. Encapsulation methods in nanoemulsions may render the protection of the flavonoid viable, as well as enable its dispersibility in aqueous media. The objective of the present study was to produce nanoemulsions (oil phase: sunflower oil) encapsulating quercetin by the emulsion inversion point method (EIP), determining operating parameters that enable a future process scale-up. A case study on the incorporation of nanodispersions into chicken patê was also carried out. The production parameters evaluated were: type and concentration of surfactant (SOR ratio, surfactant:oil ratio), soybean oil concentration, cosolvent concentration and stirring speed. Nanoemulsions were produced using two different surfactants, Tween 80 and Brij 30. The percentages of encapsulated quercetin were 0.15 and 0.30% (m / m). Among these, the concentration of 0.30% was the most feasible for application in chicken pâté, since it presented better droplet size distribution (hydrodynamic diameter), did not present significant variation of lipid oxidation and higher capacity of preserving encapsulated quercetina for a period of 90 days. The interfacial tension values obtained show that quercetin lowered the interfacial tension of the system, which may indicate that quercetin forms a complex with the surfactants used, a fact that decisively influences its location in the nanodroplets. Among the formulations tested in chicken pâté containing quercetin, only the formulation using free quercetin did not show good acceptance evaluation on the color and taste itens. Such an evaluation was important as it justifies the need for the incorporation of quercetin into nanoemulsions in order to not cause significant sensorial changes in the product.
239

Desempenho lumínico em edificação escolar com estratégias sustentáveis e bioclimáticas : um estudo de caso

Krum, Christiane Cunha January 2011 (has links)
Frente ao desenfreado desenvolvimento da sociedade nas suas diversas esferas, busca-se novas maneiras de habitar o planeta, de forma a preservá-lo para as futuras gerações. Uma das vertentes nas quais o homem pode intervir e, assim, ajudar a preservar os recursos naturais do planeta, diz respeito à busca por economia energética. Em edificações de uso prolongado e onde são desenvolvidas atividades visuais intensas, o uso da luz natural é de extrema valia, não apenas resultando em economia de energia elétrica, mas também contribuindo para o conforto ambiental e bem estar de seus usuários através dos benefícios proporcionados por esta luz. Portanto, o uso da luz natural sendo complementada pela luz artificial é de profunda importância para o bom desempenho lumínico da edificação. Fruto dos trabalhos desenvolvidos pelo grupo de pesquisa em Edificações e Comunidades Sustentáveis do NORIE/UFRGS, a edificação escolar analisada nesta pesquisa foi projetada a partir de estratégias sustentáveis e bioclimáticas. Esta pesquisa tem como objetivo avaliar o desempenho lumínico de uma sala de aula da edificação supracitada, para, assim, proporcionar considerações acerca das decisões projetuais tomadas. A metodologia utilizada para a obtenção destas informações consistiu na análise das intenções projetuais dos autores da edificação, no levantamento das características físicas e construtivas da escola e em medições lumínicas realizadas ao longo de um dia, em datas próximas aos solstícios e equinócios, no interior e no exterior da edificação. E, para verificar a eficiência de alguns elementos da edificação e propor melhorias de forma a incrementar o seu desempenho lumínico, foram realizadas simulações da sala de aula. A partir dos resultados gerados nesta pesquisa pretende-se não apenas fornecer informações sobre o desempenho lumínico desta edificação, como levantar questões que poderão embasar futuros projetos preocupados em fazer um melhor uso desta fonte natural, gratuita e de qualidade: a luz natural. / New manners on how to inhabit the planet are sought due to the increasing society development, in order to preserve it for the future generation. The seeking for low-energy consumption alternatives is one of the key issues the man can intervene in order to preserve earth´s natural resources. The usage of natural light is extremely valuable in edifications where intensive visual activities are developed; not only resulting in electric energy savings but also contributing for the environmental comfort and users´ well-being through the benefits provided by this light. Hence, the natural light usage complemented by the artificial light has a great importance in the edification´s luminous performance. The scholar edification analyzed by this research was projected with sustainable and bioclimatic strategies, based on information developed by NORIE/UFRGS research group on Sustainable Edifications and Communities. This research’s objective is to evaluate the luminous performance of one of the scholar edification´s classroom in order to provide considerations in relation to the project´s decisions. The selected methodology for these information gathering was based on the edification authors´ project intensions, the physical and constructive school´s characteristics, and the luminous measurements taken along a hole day. These measurements were taken on dates close to solstices and equinoxes, in the edification´s interior and exterior. Classroom model simulations were developed in order to verify some building´s elements efficiency and to propose improvements for its luminous performance. The research´s results intends to provide relevant information about this particular edification´s luminous performance; and also to rise useful knowledge for future projects regarding daylight usage, a free and natural source of energy.
240

Nouvelles solutions et classification du superpotentiel et du potentiel de Kähler compatibles avec une brisure de la supersymétrie à basse énergie induite par la gravitation / New solutions and classification of the Kähler potential and the superpotential compatibles with gravity-mediated supersymmetry breaking at low energy

Tant, Damien 01 December 2016 (has links)
L’introduction d’une symétrie entre les bosons et les fermions, appelée supersymétrie, étend de manière naturelle le modèle standard de la physique des particules. Néanmoins, une telle symétrie n’a jamais été observée dans la nature : elle doit être nécessairement brisée. L’étude de la brisure de la supersymétrie induite par la gravitation est le coeur du travail effectué dans cette thèse. En 1983, Soni et Weldon ont classifié les formes analytiques des deux fonctions fondamentales - le potentiel de Kahler et le superpotentiel - de manière à conduire à une supersymétrie brisée à basse énergie. Depuis, les analyses phénoménologiques sont basées sur cette classification. Le principal résultat du présent manuscrit est de démontrer l'incomplétude de leur classification. Pour un potentiel de Kahler dit canonique, une classification complète est réalisée tandis qu'un début de classification est proposé pour le cas non-canonique. Dans les deux cas, de nouvelles solutions sont établies menant à de possibles nouvelles conséquences phénoménologiques à basse énergie. L'apport de candidats pour le problème de la matière noire fait partie des contributions majeures des modèles supersymétriques. En parallèle du travail de classification, le développement d'un nouveau calculateur, permettant d'estimer la densité relique de matière noire dans l'Univers, est également proposé. / Supersymmetry extends naturally the Standard Model through the introduction of a new symmetry between bosons and fermions. However, such symmetry has never been observed in nature : Supersymmetry must be broken. Gravity-mediated supersymmetry breaking is the main subject of this doctoral thesis. In 1983, Soni and Weldon classified the analytical forms of the two fundamental functions - the Kahler potential and the superpotential - leading to a consistent low energy broken Supersymmetry. Up to nowadays, this classification has been used for phenomenological model building. The main result of the current thesis demonstrates the incompleteness of their classification. A complete classification is presented for a given canonical Kahler potential while a first sight of the classification is proposed for the non-canonical case. From these assumptions, new solutions are obtained leading to new possibilities for model building at low energy.The proposition of new dark matter candidates is one of the several contributions coming from supersymmetric models. In addition of the new classification, the development of a new generator, allowing to estimate the relic density of dark matter particles, is also proposed.

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