Η σύγχρονη αρχιτεκτονική στρέφεται σε λύσεις που έχουν ως στόχο την εξοικονόμηση ενέργειας, χωρίς όμως να επιβαρύνεται σε μεγάλο βαθμό η απόδοση του επεξεργαστή. Ιδιαίτερα οι υπερβαθμωτοί (superscalar) επεξεργαστές που επιτρέπουν εκτέλεση εκτός σειράς (out-of-order execution) διακρίνονται από υψηλή κατανάλωση ενέργειας, εξαιτίας των πολύπλοκων δομών που χρησιμοποιούν για την αύξηση της απόδοσης. Η δυναμική ρύθμιση τάσης – συχνότητας (DVFS) αποτελεί μία ευρέως χρησιμοποιούμενη τεχνική για την επίτευξη εξοικονόμησης ενέργειας. Μειώνοντας τη συχνότητα λειτουργίας ενός κυκλώματος, είναι δυνατόν να μειωθεί και η τάση τροφοδοσίας του κυκλώματος. Με τον τρόπο αυτό ελαττώνεται και η ενέργεια που καταναλώνει το κύκλωμα. Σκοπός της εργασίας είναι η ανάπτυξη ενός μηχανισμού πραγματικού χρόνου που θα ρυθμίζει τη συχνότητα και την τάση λειτουργίας ενός superscalar, out-of-order επεξεργαστή ώστε να επιτυγχάνεται εξοικονόμηση ενέργειας χωρίς μεγάλη μείωση της απόδοσης του επεξεργαστή. Αυτό μπορεί να επιτευχθεί ελαττώνοντας τη συχνότητα και την τάση κατά τις περιόδους που ο επεξεργαστής εκτελεί πολλές λειτουργίες μνήμης. Η εξομοίωση του μηχανισμού μας για μία σειρά από μετροπρογράμματα δείχνει ότι μπορούμε να επιτύχουμε μεγάλη εξοικονόμηση ενέργειας χωρίς σημαντική αύξηση του χρόνου εκτέλεσης των προγραμμάτων. / Modern research in computer architecture focuses on techniques whose purpose is to save energy, without much loss in processor's performance. Especially superscalar processors that allow out of order execution are characterized by high energy consumption, because of the complex structures the use in order to increase performance. Dynamic Voltage - Frequency Scaling (DVFS) is a widely used technique for energy saving. Reducing the frequency of the processor's clock, it is possible to reduce the supply voltage. In this way the consumed energy is also reduced. The purpose of this diploma thesis is to create a real time mechanism that will scale the frequency and the voltage of a superscalar, out of order processor so that the processor saves energy without much loss in processor's performance. This can be made by reducing the frequency and the voltage during the periods that the processor executes many memory functions. The simulation of our mechanism for a variety of benchmarks proved that we can save much energy without much increase in the benchmark's execution time.

Κύριος στόχος της διπλωματικής αυτής εργασίας είναι η διερεύνηση τεχνικών βελτίωσης της προσφερόμενης ποιότητας υπηρεσιών (QoS) σε ένα περιβάλλον συνλειτουργίας πολλαπλών HAPs. Στο περιβάλλον αυτό έχουμε διαφορετικούς τύπους χρηστών που μοιράζονται την περιοχή κάλυψης και το εύρος ζώνης. Παρουσιάζεται το θεωρητικό υπόβαθρο της μελέτης αυτής που περιλαμβάνει τη θεωρία τηλεπικοινωνιακής κίνησης. Αναπτύσσουμε ένα αναλυτικό μοντέλο ώστε να περιγράψουμε το περιβάλλον συνλειτουργίας στο οποίο έχουμε δύο κατηγορίες χρηστών. Η μία κατηγορία αποτελείται από χρήστες που έχουν πλήρη πρόσβαση στα HAPs, ενώ η άλλη κατηγορία αποτελείται από χρήστες με περιορισμένη πρόσβαση στα HAPs. Για να επιτύχουμε αυτή τη βελτίωση του QoS εφαρμόζουμε διάφορους μηχανισμούς περιορισμού. Σκοπός μας είναι να περιοριστεί η πρόσβαση στους πόρους του καναλιού για τους χρήστες με πλήρη πρόσβαση στα HAPs, ώστε να υπάρχει μεγαλύτερη πιθανότητα πρόσβασης για τους χρήστες με περιορισμένη πρόσβαση στα HAPs. Παρουσιάζονται και αναλύονται διάφοροι περιορισμοί με στόχο την εύρεση του καταλληλότερου για την επίτευξη μιας ισορροπημένης και χαμηλής πιθανότητας απόρριψης κλήσης. Αναλύεται, επίσης, και επεξηγείται η παρουσία φαινομένων παρεμβολής και πολυόδευσης στο σύστημά μας καθώς και η εξοικονόμηση συχνοτήτων. / The main objective of this thesis is to investigate techniques for improvement the Quality of Service (QoS) in an environment of multiple HAPs. In this environment there are different user types which share coverage area and radio spectrum. It is presented the theoretical background of this study that includes theory telecommunication traffic. We develop an analytical model to describe system behavior of a coexistence scenario containing two user groups, which have full and limited HAP availability. In order to achieve this improvement of QoS, operate different restrictions. Our aim is to limit access to channel resources to users with full access to HAPs, so that there is a greater probability of access for users with limited access to HAPs. Different types of restriction function are analyzed trying to find the most suitable for achieving a balanced low probability performance to both user groups simultaneously. It is also explained the presence of interference, small-scale fading and saving frequencies.

Este trabalho propõe uma arquitetura reutilizável que permite a gerência de uma infraestrutura de suporte para aplicações Web, utilizando máquinas virtuais. O objetivo da arquitetura é garantir qualidade de serviço, atuando nos servidores físicos (hospedeiros) ou manipulando as máquinas virtuais, e avaliando o cumprimento das restrições de operação (tempo de resposta máximo). Além disso, através do uso racional dos recursos utilizados, a proposta visa à economia de energia. O trabalho também inclui uma avaliação de desempenho realizada sobre um sistema implementado com base na arquitetura. Esta avaliação mostra que a proposta é funcional e o quanto ela pode ser vantajosa do ponto de vista do uso de recursos, evitando desperdício, mantendo-se ainda a qualidade de serviço em níveis aceitáveis pela aplicação.

The current boilers at the Brunna plant were installed in 1979 using oil and solvents to produce steam for the production and heating of the plant. To reduce the carbon dioxide emissions in compliance with Fresenius Kabi strategy a new biofuel boiler is about to be installed. Since the steam demand has been reduced during the years and it’s expensive to install a new boiler this study has been performed to calculate the actual steam demand for the plant at different scenarios. A smaller boiler requires a lower investment, achieves higher efficency and contributes to reduced carbon dioxide emissions. This report is intended to supply the management with information so that a decision regarding investments and employees can be made. The result is presented as different possible scenarios that are of great importance when deciding which boiler effect that is needed. Destillation, heating and the production have a major impact and must be considered when installing a new boiler. The results show that a boiler should be between 2-4 MW net effect depending on which scenario that is most likely to occur.

This research is guided from the perspective of Pragmatics, and it is situated in the theoretical and methodological field of Interactional Sociolinguistics and Conversation Analysis. The objective is to analyze the conversation between participants in a specific type of interaction, that is TV news interviews, conducted in the news of state of Alagoas local TV channels, in order to investigate the saving face process on the run. The theoretical framework is based on studies developed by Goffman (1967) and research work on politeness as an element of saving face developed further by Brown & Levinson (1987). For the research methodology I adopted the proposal of ethnographic microanalysis to analyze in detail each of the interactions recorded in audio and video, through observation and transcription of the conversation, to investigate through the accuracy required, the saving face discursive practice of the interlocutors. The corpus consisted of six interviews that were collected during the initial period of the survey. The results reveal a broad and diverse discursive practice of saving face in the discourse of the interaction in focus. The topic being discussed in every interaction is an element that influences the practice of face saving, especially when taking into account certain contextual components, such as personal/professional identity of the person who is speaking on the topic and its relation with it. The distance from the speech is a resource used repeatedly by both interviewer and interviewee, and there is evidence that a party perceives the occurrence of this practice in the speech of the other. The reaction to cooperate or try to disprove this intention will also vary depending on the contextual elements, not only on who is talking, but mainly from what is being said. In this regard, it was noticed that when the disclosure happens it is not always a threat to face. Finally, it was noticed that politeness is a discursive practice widely used by both parties in the saving face process, and by making use of this practice the interviewer, as one who directs the interaction at first, can achieve the goal of their work as well as mantaining a harmonious interaction with their interviwees. / Esta pesquisa é orientada sob a perspectiva dos estudos da Pragmática, e situa-se no campo teórico-metodológico da Sociolinguística Interacional (SI) e da Análise da Conversação (AC). O objetivo é analisar a conversa que ocorre entre os participantes de um tipo específico de interação, as entrevistas jornalísticas de TV, realizadas e veiculadas em noticiários de emissoras locais - do estado de Alagoas -, com o propósito de investigar como se dá o processo de negociação das faces em jogo. A fundamentação teórica tem como base os estudos sobre a negociação da face desenvolvidos por Goffman (1967) e o trabalho de pesquisa sobre a polidez como um elemento de negociação da face, realizado posteriormente por Brown & Levinson (1987). Como procedimento metodológico, adotei a proposta da microanálise etnográfica, e analisei detalhadamente cada uma das interações orais gravadas em áudio e vídeo, através da observação e transcrição da conversa, para investigar com a acuidade necessária, a prática discursiva de negociação da imagem dos interlocutores na interação. O corpus constituiu-se da transcrição de seis entrevistas, e foi coletado durante o período inicial de realização da pesquisa. Os resultados revelam uma ampla e diversificada prática discursiva de negociar a imagem no discurso da interação em foco. O tema que se discute em cada interação é um dos elementos que influencia na prática da negociação da imagem, principalmente ao considerar certos componentes contextuais, como a identidade pessoal/profissional da pessoa que está falando sobre o tema e em que sentido, a ele, a pessoa está relacionada. O afastamento dos interlocutores do discurso é um recurso recorrentemente usado na fala de ambos, entrevistador e entrevistado, e há evidências de que um interlocutor percebe a ocorrência dessa prática no discurso do outro. A reação de colaborar com o afastamento ou de tentar desmascarar essa intenção também vai variar a depender dos elementos contextuais, não só de quem está falando, mas, principalmente, do quê se está falando. A esse respeito, percebeu-se também que quando há o desvelamento, esse nem sempre se constitui em um ato ameaçador das faces. Por fim, percebeu-se que a polidez é uma prática discursiva muito usada pelos dois interlocutores no processo da negociação da imagem, e que o entrevistador, como aquele que a princípio dirige a interação, ao fazer uso dessa prática, consegue atingir o objetivo do seu trabalho sem abrir mão de manter um contato harmonioso na interação com o entrevistado.

La montée du poids de la finance est, pour une part au moins, une réponse à la mise en place et en œuvre de stocks de capital productif toujours plus importants et à l’accumulation, qui en est la contrepartie, d’une masse toujours plus grande d’actifs financiers. A ce premier facteur qui fait de la montée du poids de la finance une conséquence en partie « mécanique » du développement économique, s’en est toutefois ajouté un autre : une montée incontestable du rôle des marchés financiers qui est venue modifier en profondeur la façon dont les risques liés au financement de cette accumulation de capital productif sont désormais portés. Le mécanisme d’allocation de l’épargne et de prise de risques mis à disposition de nos économies par les marchés financiers n’a toutefois ni la puissance ni la robustesse que lui prêtent les tenants de la libéralisation financière. La masse de risques qu’un système financier peut porter est fonction des contraintes de prudence imposées par les régulateurs, mais aussi de l’attitude face au risque des acteurs financiers. Le caractère cyclique de cette dernière a une incidence majeure sur la stabilité financière : le système peut brutalement ne plus parvenir à trouver seul son équilibre. / The rise of finance in developed economies is, for a part at least, a response to the provision and use of an ever growing volume of productive capital stocks and to the accumulation of an ever growing amount of financial assets, which is its counterpart. It is, however, far from being only a mechanical consequence of the development of the real sphere of the economy: the development of financial markets has also radically altered the way financial risks associated with the financing of the accumulation of capital stocks are now borne. The mechanisms allocating savings and redistributing financial risks at the disposal of our economies have, however, neither the efficiency nor the robustness advocated by the proponents of financial liberalization. The mass of risks a financial system can absorb depends not only on prudential regulatory constraints, but also on financial agents’ attitude towards risk. The pro-cyclical nature of the latter has a major impact on financial stability: the system can suddenly be unable to strike a balance on its own.

Este trabalho propõe uma arquitetura reutilizável que permite a gerência de uma infraestrutura de suporte para aplicações Web, utilizando máquinas virtuais. O objetivo da arquitetura é garantir qualidade de serviço, atuando nos servidores físicos (hospedeiros) ou manipulando as máquinas virtuais, e avaliando o cumprimento das restrições de operação (tempo de resposta máximo). Além disso, através do uso racional dos recursos utilizados, a proposta visa à economia de energia. O trabalho também inclui uma avaliação de desempenho realizada sobre um sistema implementado com base na arquitetura. Esta avaliação mostra que a proposta é funcional e o quanto ela pode ser vantajosa do ponto de vista do uso de recursos, evitando desperdício, mantendo-se ainda a qualidade de serviço em níveis aceitáveis pela aplicação.

A lot of time is spent on manual software testing. When software can interact with exponentially more and more components the number of tests required will increase at the same rate. Automation of these manual tests has been previously shown that a time-saving can occur with test automation. When tests need to be done on software that interacts with physical components the results of testing automation are harder to predict. This thesis aims to explain the impact of physical components on the development and the result of test tools developed for use on automated tests on objects with physical components. In this work, a test tool for automatic regression testing for height adjustable table legs were developed. The method used to design the tool was Design Science Research where, for example, TESLA was adapted for use in automated tests with physical components. TESLA is a language for specifying test cases and allowing test automation with embedded systems that was implemented in the test tool's design which could be used to automatically generate scripts and automatically executes test cases. With the development and design of the testing tool, the thesis attempted to answer how a test tool should be designed when physical components are included in the test object and how the measurement accuracy of the tool may affect the test result. Experiments have been carried out during the development process where regression tests have been performed according to a test protocol. During these experiments a test protocol is executed. One manually by hand and one is done automatically with the testing tool. The results of the experiments show that the execution of the test protocol execution with the test tool gave a time saving of 35% compared to the manual tests. The physical components of the test object were shown to affect the automatic execution time negative and further analysis of previous research has shown that this result is insufficient to justify the large initial time that is required to automate tests. / Mycket tid spenderas ofta på manuell testning av mjukvara. Då en mjukvara kan interagera med exponentiellt mer komponenter så kommer antalet tester att öka i samma takt. Automatisering av dessa manuella tester har med tidigare forskning bevisat att en tidsbesparing kan ske med testautomatiseringen. Då tester måste utföras på mjukvara som interagerar med fysiska komponenter så är resultaten av testautomatisering inte lika klara och arbetet syftar på att förklara de fysiska komponenternas påverkan på utveckling och resultatet för testverktyg som används till automatisk testning av testobjekt med fysiska komponenter. I detta arbete så framtogs ett testverktyg för automatiska regressionstest för höj och sänkbara bordsben. Metoden som användes för att utveckla verktyget var Design Science Research där till exempel TESLA anpassades för användning i automatiska tester med fysiska komponenter. TESLA är ett språk för att specificera testfall och möjliggöra testautomatisering i inbyggda system implementerades i testverktygets design och kunde då automatisk generera skript och automatiskt exekvera testfall. Med utvecklingen och design av testverktyget så försökte arbetet svara på hur ett testverktyg bör vara designat när fysiska komponenter ingår i testobjektet och hur testverktygets mätnoggrannhet kan påverka testresultatet. Experiment har utförts under arbetets gång där regressionstester har utförts enligt ett testprotokoll. Under experimenten utfördes ett testprotokoll manuellt för hand och ett automatiskt med testverktyget. I båda situationerna så mättes testprotokollets utförande i tid. Testverktyget gav en tidsbesparing på 35% visavi de manuella testerna. Testobjektets fysiska komponenter hade en negativ påverkan på den automatiska exekveringstiden och vidare analys av tidigare forskning har visat att detta resultat inte räcker för att motivera den stora initiala tidsinvestering som krävs för att automatisera tester.

South Africa is trailing behind its BRICS counterparts in terms of Gross national Savings rates. South Africa stands at around 16% of gross domestic product, fellow BRICS members China and Russia are standing at approximately 52% and 22% respectively. South Africa saw a decline from approximately 30% GDP to savings ratio before 1994 to the current level of approximately 16%. The trend has been very similar in comparison with India. The other similarity between these BRICS countries is that they all have seen very rapid growth. All economic indicators have indicated that the economies of the BRICS nations are very strong and have been performing at a superior level to South Africa. South Africa compares even worse with regards to household savings versus its BRICS counterparts. Various arguments and explanations as to why this is so come up on a number of social, government and corporate platforms. The “aspirational” culture is widely blamed for the poor showing of South African households when it comes to savings. The South African financial sector is very sophisticated and is widely blamed for the encouraging consumption and even worse credit consumption. An analysis done by Ecnometrics found that amongst the significant determinants of household saving rates are: uncertainty (inflation), income level, public sector savings, development’s in the global economy and government economic policy. The study revealed that the above factors were very influential in the rapid economic growth and increased per capita net worth seen of the most BRICS countries. The correlation between saving/investment and consumption/irresponsible consumer behavior is indicated to be a very strong one and takes a very longtime to evolve. This requires outrooting certain societal norms, attitudes and culture and replacing it with a brand new behavior, beliefs and aspirations. Role players that emerge as strong drivers in this phenomena is the societal culture however the other role player who prove to be prominent are the policy makers. In most cases the economic and gross national saving rates coincided with major economic policy reforms in the countries that have performed well.

Low domestic saving rates make South Africa highly dependent on foreign capital inflows to fund higher investment levels. These inflows are highly volatile and may prove to be unsustainable in the long-run. This study analyses the determinants of private saving in South Africa, with specific reference to the decline in private saving rates that occurred at a time of higher economic growth prior to the 2008 global financial crisis. The Johansen cointegration method is used to estimate separate vector error correction models (VECM) in order to assess the effect of specific variables on both corporate and household saving. The results obtained that are common to both corporate and household savmg show that the govemment budget balance negatively impacts private saving rates though the offset is less than one. The real prime overdraft rate positively impacts private saving, although the result is small . The impact of real Gross Domestic Product (GDP) is positive. In recent years, however, private saving rates fell alongside higher economic growth, which may reflect a structural change in corporate saving behaviour. The results distinct to the corporate saving model show that commodity prices have a negative impact on corporate saving. This does not conform to a priori expectations, but is supported by the behaviour of these two variables in recent years. Foreign savings were found to impact negatively on corporate saving. This result is important, since the dependence of the South African economy on foreign capital inflows to fund higher investment levels is reflected by high current account deficits during recent periods of economic growth. Evidence of financial liberalization negatively impacting on private saving in South Africa due to the removal of borrowing constraints was found. A negative relationship was found between corporate saving and investment demonstrating that corporations have reduced levels of retained eamings for funding investment expenditures. The results distinct to the household saving model provide evidence of a negative wealth effect in South Africa, with rising housing wealth found to increase consumption. Evidence of households "piercing the corporate veil" in South Africa was found. Therefore, households view corporate saving behaviour as essentially being conducted on their behalf. This finding and the finding that the offset between the budget deficit and private saving is less than one suggest that counter-cyclical fiscal policy will be an important policy response for achieving higher domestic saving rates in South Africa.