Οι μνήμες αποτελούν την κύρια ανησυχία σε αρχιτεκτονικές χαμηλής κατανάλωσης και υψηλών ταχυτήτων. Σε έναν επεξεργαστή SOC (System on chip)περιορίζουν τις περισσότερες φορές την ταχύτητα και αποτελούν το κύριο μέρος της κατανάλωσης ενέργειας.Διάφορες τεχνικές έχουν προταθεί για τη μείωση της ισχύος σε κρυφές μνήμες. Στην παρούσα εργασία παρουσιάζονται τεχνικές μείωσης της δυναμικής ισχύος με μείωση της παράλληλης διακοπτικής δραστηριότητας. Οι τεχνικές αυτές αναπτύχθηκαν στη κρυφή μνήμη του Cellsim εξομοιωτή, βασισμένο στη λογική του Unisim εξομοιωτή, ενώ όλα τα ενεργειακά αποτελέσματα εξήχθησαν με το εργαλείο Cacti. Η εφαρμογή των συγκεκριμένων τεχνικών επέφερε σημαντικές μειώσεις στην κατανάλωση της δυναμικής ισχύος της κρυφής μνήμης για όλα τα μετροπρογράμματα που χρησιμοποιήθηκαν. / Memories are the main concern in low power and high speed architecture. In a Soc (System on chip) processor memories most of the time limit the speed and become the main part of power consumption. Various techniques have been proposed for power reduction in cache memories. In this thesis are presented different power reduction techniques by reducing parallel switching activity. These techniques were developped in the cache memory of Cellsim emulator, based on the logic of Unisim emulator, while all power results were extracted with the Cacti tool. The application of the specified techniques brought serious reductions in power consumption of cache memory for all the benchmarks that were used.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-02T22:55:04Z No. of bitstreams: 1 HerbertSenzanoLopes_DISSERT.pdf: 1964831 bytes, checksum: a1f3b710808bf3ed42490612f2700bca (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-04T00:31:31Z (GMT) No. of bitstreams: 1 HerbertSenzanoLopes_DISSERT.pdf: 1964831 bytes, checksum: a1f3b710808bf3ed42490612f2700bca (MD5) / Made available in DSpace on 2016-03-04T00:31:31Z (GMT). No. of bitstreams: 1 HerbertSenzanoLopes_DISSERT.pdf: 1964831 bytes, checksum: a1f3b710808bf3ed42490612f2700bca (MD5) Previous issue date: 2014-12-23 / A parte pesada do petr?leo pode ser utilizada para in?meras finalidades, uma delas ? a obten??o de ?leos lubrificantes. Com base nesse contexto, muitos pesquisadores v?m estudando alternativas de separa??o desses constituintes de petr?leo bruto, entre elas pode ser citada a destila??o molecular, uma t?cnica de evapora??o for?ada diferente dos outros processos convencionais presentes na literatura. Este processo pode ser classificado como um caso especial de destila??o a alto v?cuo com press?es que chegam a atingir faixas extremamente baixas da ordem de 0,1 Pascal. As superf?cies de evapora??o e de condensa??o devem apresentar uma dist?ncia entre si da ordem de grandeza do percurso livre m?dio das mol?culas evaporadas, isto ?, as mol?culas evaporadas facilmente atingir?o o condensador, pois as mesmas encontrar?o um percurso sem obst?culos, o que ? desej?vel. Logo, a principal contribui??o deste trabalho consiste na simula??o do processo de destila??o molecular de filme descendente do petr?leo. O petr?leo bruto foi caracterizado utilizando o UniSim? Design R430 e o Aspen HYSYS? V8.5. Com os resultados desta caracteriza??o foram efetuados, em planilhas de c?lculo no Microsoft? Excel?, os c?lculos das propriedades f?sico-qu?micas dos res?duos de uma amostra de petr?leo, i.e., termodin?micas e de transporte. De posse dessas propriedades estimadas e das condi??es de contorno sugeridas pela literatura, foram resolvidas as equa??es dos perfis de temperatura e concentra??o atrav?s do m?todo de diferen?as finitas impl?cito utilizando a linguagem de programa??o Visual Basic? (VBA) for Excel?. O resultado do perfil de temperatura apresentou-se coerente com os reproduzidos pela literatura, havendo em seus valores iniciais uma leve distor??o em consequ?ncia da natureza do ?leo estudado ser mais leve que o da literatura. Os resultados dos perfis de concentra??o mostraram-se eficientes permitindo perceber que as concentra??es dos mais vol?teis diminuem e as dos menos vol?teis aumentam em fun??o do comprimento do evaporador. De acordo com os fen?menos de transporte presentes no processo, o perfil de velocidade tende a aumentar at? um ponto m?ximo e em seguida diminui e a espessura do filme diminui, ambos em fun??o do comprimento do evaporador. Conclui-se que o c?digo de simula??o em linguagem Visual Basic? (VBA) ? um produto final do trabalho que permite aplica??o para a destila??o molecular do petr?leo e de outras misturas similares. / The heavy part of the oil can be used for numerous purposes, e.g. to obtain lubricating oils. In this context, many researchers have been studying alternatives such separation of crude oil components, among which may be mentioned molecular distillation. Molecular distillation is a forced evaporation technique different from other conventional processes in the literature. This process can be classified as a special distillation case under high vacuum with pressures that reach extremely low ranges of the order of 0.1 Pascal. The evaporation and condensation surfaces must have a distance from each other of the magnitude order of mean free path of the evaporated molecules, that is, molecules evaporated easily reach the condenser, because they find a route without obstacles, what is desirable. Thus, the main contribution of this work is the simulation of the falling-film molecular distillation for crude oil mixtures. The crude oil was characterized using UniSim? Design and R430 Aspen HYSYS? V8.5. The results of this characterization were performed in spreadsheets of Microsoft? Excel?, calculations of the physicochemical properties of the waste of an oil sample, i.e., thermodynamic and transport. Based on this estimated properties and boundary conditions suggested by the literature, equations of temperature and concentration profiles were resolved through the implicit finite difference method using the programming language Visual Basic? (VBA) for Excel?. The result of the temperature profile showed consistent with the reproduced by literature, having in their initial values a slight distortion as a result of the nature of the studied oil is lighter than the literature, since the results of the concentration profiles were effective allowing realize that the concentration of the more volatile decreases and of the less volatile increases due to the length of the evaporator. According to the transport phenomena present in the process, the velocity profile tends to increase to a peak and then decreases, and the film thickness decreases, both as a function of the evaporator length. It is concluded that the simulation code in Visual Basic? language (VBA) is a final product of the work that allows application to molecular distillation of petroleum and other similar mixtures.