This research initiative attempts to empirically determine, with reality-based evidence from un-biased sources, the cost disadvantage, energy advantage, and expected pay-back period associated with building an above-code residence in Victoria, BC. In addition, this initiative created a much-needed benchmark for contractors to gain a firm understanding of the construction details required to achieve the various levels of the “Step-Code” in the newest edition of the BCBC. It was important to gain this information specific to Victoria B.C. to make an appropriate estimation of the actual “cost challenge” for building above code in the local housing market. This was accomplished through: a simulated tendering process with local contractors, an energy analysis of a case-study residence with the same floor plan, and an in-depth study into the variables governing time-to-amortization. The contractors provided quotes for an “above code” residence (ACR), and a minimum-code residence (MCR) with the same floor plan. The results were then compared to the as-built construction costs of the residence. When compared to the MCR, it was found that the ACR has a cost-disadvantage of approximately 22.5% ($74,400), an energy advantage of 22.5 kWh/m2/yr , and a payback period of over 79 years when a fuel inflation rate of 2% is considered. However, many of the components in the ACR assemblies were either for aesthetic appeal (metal-roofing), or comfort (floor-cavity insulation), and therefore it was possible to reduce the cost-disadvantage to just 2.1% ($7,759), while maintaining an energy advantage of 15kWh/m2/yr and step-level 3 designation. This was dubbed the hybrid-residence (HR) as it employed a combination of above-code and minimum-code construction assemblies. The HR has a pay-back period of approximately 16 years when the same inflation rate is expected in the price of fuel. / Graduate

La plupart des infrastructures de cloud efficace en énergie proposées dans la littérature ne tiennent pas compte de la disponibilité électrique et des énergies renouvelables dans leurs modèles. L’intégration des énergies renouvelables dans les centres de données réduit considérablement leur consommation d’énergie et leur empreinte carbone. Étant donné que l’énergie renouvelable est intermittente et fluctue en fonction du temps, elle est habituellement sous-utilisée. Nous abordons le problème de l’amélioration de l’utilisation des énergies renouvelables dans un centre de données unique et étudions deux approches : la planification opportuniste et le stockage de l’énergie. Nos résultats démontrent que les deux approches permettent de réduire la consommation d’énergie non-renouvelable sous différentes configurations. Nous étendons ce travail au contexte des Edge Clouds et de l’Internet des Objets dans le cas de l’analyse de flux de données. Nous montrons comment rendre les Edge Clouds plus verts avec une production d’énergie renouvelable sur site combinée à un stockage d’énergie et à une dégradation de performance des applications des utilisateurs. / Most of the energy-efficient Cloud frameworks proposed in literature do not consider electricity availability and renewable energy in their models. Integrating renewable energy into data centers significantly reduces the traditional energy consumption and carbon footprint of these energy-hungry infrastructures. As renewable energy is intermittent and fluctuates with time-varying, it is usually under-utilized. We address the problem of improving the utilization of renewable energy for a single data center and investigate two approaches: opportunistic scheduling and energy storage. Our results demonstrate that both approaches are able to reduce the brown energy consumption under different configurations. We extend this work to the context of Edge Clouds and Internet of Things on the use case of data stream analysis. We show how to make Edge Clouds greener with on-site renewable energy production combined with energy storage and performance degradation of the users’ applications.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work proposes improve the study about the efficiency indicators development, to be use in irrigation equipment for pivot. At first, it sought to make some clarifications about the current state of the irrigations technical, and how the society perceives it. In relation to the discussion of the technical evaluation, it sought to deliberate about the design project, since it theoric reason, even the best way of implementation thereof, with the goal to add knowledge to the area. The pivot equipment also was reason for presentation, answering the goal to clarify the terms and innovations. The main question discussed in the thesis concerns the theoretical foundation and the discussion on the question around the pursuit of technical efficiency. To discuss the implementation of energy efficiency measures in irrigation systems for pivot, it began with the methodology used for the evaluation of these systems. Right after, were calculated the performance indicators, and suitable the equipments in a standard efficiency, so to encompass the conditions of the energy and agricultural performance of the irrigation. The evaluation nowadays used to irrigation systems, is mainly carried over the Application Efficiency, with the help of uniformity indicators and with the installed potency evaluation. With this idea of indicator, it has a same parameter to compare installed systems in different conditions; this data has bigger applicability to assessments that are performed on equipment. The indicators were applied in 39 irrigation systems for pivot, in two regions of Rio Grande do Sul: Cruz Alta and Santo Augusto Region. With most medium-sized equipment (40 to 100 ha), with gap geometric mean total of 47,4 meters. The incomes of motorpump set ranged from 58% to 81%, with maximum potential reduction of power equipment in the Region of Cruz Alta of 29,41cv, and in the Region of Santo Augusto of 31,32cv. It was possible to complete that, according to the standard Energy Efficiency, The Specific Consumption Standard for irrigation, proposed by Lima (2008), 72% of the facilities from Region of Cruz Alta are above the standard (8,68 kWh.mm-1.ha-1.100m-1), and in the Region of Santo Augusto 64,28% are with the Consumption above standard. / Este trabalho teve por objetivo aprimorar o estudo acerca do desenvolvimento de indicadores de eficiência para serem utilizados em equipamentos de irrigação por pivô central. Inicialmente procurou-se realizar alguns esclarecimentos sobre o estado atual da técnica de irrigação, e como a sociedade a percebe. Em relação a discussão sobre avaliação técnica, buscou-se discutir a concepção de projetos, desde sua fundamentação teórica, até a melhor maneira de implementação dos mesmos, com o objetivo de agregar conhecimento nesta área. O equipamento pivô central também foi motivo de apresentação, atendendo ao objetivo do esclarecimento de termos e inovações. A principal questão abordada neste trabalho diz respeito à fundamentação teórica e a discussão em torno da busca da eficiência técnica. Para discutir a implementação de medidas de eficiência energética em sistemas de irrigação por pivô central, iniciou-se com a metodologia utilizada para a avaliação destes sistemas. Após, foram calculados indicadores de eficiência e adequados os equipamentos em um padrão de eficiência, de forma a englobar as condições de desempenho energético e agrícola da irrigação. As avaliações atualmente utilizadas para sistemas de irrigação são realizadas principalmente por meio da Eficiência de Aplicação, com auxílio de coeficientes de uniformidade e com a avaliação da potência instalada. Com esta nova concepção de indicador, tem-se um mesmo parâmetro para comparação de sistemas instalados em condições diferenciadas; os dados tem maior aplicabilidade para as avaliações que são realizadas nos equipamentos. Os indicadores foram aplicados em 39 sistemas de irrigação por pivô central, em duas regiões do Rio Grande do Sul: Região de Cruz Alta e Região de Santo Augusto, onde a maioria dos equipamentos de porte médio (40 a 100 ha), tinham desnível geométrico total médio de 47,4 metros. Os rendimentos dos conjuntos motobomba variaram de 58 a 81%, com potencial máximo de redução de potência em equipamento na Região de Cruz Alta de 29,41 cv, e na Região de Santo Augusto de 31,32 cv. Pôde-se concluir que, segundo o Padrão de Eficiência Energética, o Consumo Específico Normalizado na Irrigação, proposto por Lima (2008), 72% dos equipamentos da Região de Cruz Alta estavam acima do padrão (8,68 kWh.mm-1.ha-1.100m-1), e na Região de Santo Augusto 64,28% dos equipamentos estavam com o consumo acima do padrão.

This paper analyzes the influence of the penetration of solar radiation through the transparent closure in consumption of energy for conditioning of the office buildings in the region of Santa Maria-RS, located in the bioclimatic Brazilian zone 2. To do this, simulations were performed in the computational program Design Builder, in a typical office environment in order to evaluate the comparative results obtained with the use of different types of glass (Solar Factor) by different percentages of area of windows and surface guidelines. The glasses used had solar factor ranging from 0.85, 0.70, 0.56 and 0.29, an opening percentage area of 20%, 50% and 80%, while the solar orientation ranged from 0° to 315° at an interval of 45°. It was observed that for the climate of the city of Santa Maria-RS, considering the daytime use of the building, the consumption of energy for cooling process has higher values compared to the heating and that this difference is directly proportional to the solar factor of the glass and the percentage of openings in the facade. Changes that contribute to a reduction of one of these lead to an increased consumption of the other, these should be analyzed jointly in the process of defining the openings, in order to obtain the lowest annual energy consumption. The simulations indicated higher expenditure of energy with heating on the facades oriented to the south, southeast, and southwest, while the higher cost for cooling occurred on facades oriented to the north, northeast, northwest, regardless of the solar factor or percentages of openings in façade. It was observed that, when established constructive guidelines regarding apertures in construction performance standards for buildings, should be considered together the percentage of area openings, Factor Solar glass and solar orientation of the facade, as the exchanges of heat and entry lighting are naturally associated with these factors in an integrated manner. / Este trabalho analisa a influência da radiação solar que penetra pelos fechamentos transparentes no consumo de energia para climatização de edifícios de escritório na região de Santa Maria RS, situado na zona bioclimática 2 brasileira. Para isso, foram realizadas simulações no programa computacional Design Builder, em um ambiente típico de escritório, visando avaliar comparativamente os resultados obtidos com o uso de diferentes tipos de vidro (Fator Solar), mediante diferentes percentuais de área de janelas e orientações de fachada. Os vidros utilizados têm valores de Fator Solar variando de 0.85, 0.70, 0.56 e 0.29, o percentual de área de abertura de 20%, 50% e 80%, enquanto a orientação solar variou de 0° a 315°, com intervalo de 45°. Foi observado, para o clima da cidade de Santa Maria-RS, considerando-se o uso diurno do edifício, que o consumo de energia para resfriamento apresenta valores mais elevados em relação ao aquecimento, e que esta diferença é diretamente proporcional ao Fator Solar do vidro e ao percentual de aberturas na fachada. Mudanças que colaboram para a redução de um destes consumos levam ao aumento do outro, devendo-se analisá-los de forma conjunta, no processo de definição das aberturas, para que se obtenha o menor consumo anual de energia. As simulações indicaram maiores gastos de energia com aquecimento nas fachadas orientadas para sul, sudeste e sudoeste, enquanto os maiores gastos com resfriamento ocorrem com fachadas orientadas a norte, nordeste e noroeste, independente do Fator Solar do vidro ou do percentual de aberturas na fachada. Foi observado que, ao serem estabelecidas diretrizes construtivas referentes a aberturas em normas de desempenho de edificações, devem ser considerados conjuntamente o percentual de área de aberturas, o Fator Solar do vidro e a orientação solar da fachada, pois as trocas de calor e entrada de iluminação natural estão associadas a estes fatores de forma integrada.

Abstract Future multimodal mobile platforms are expected to require high interactivity in their applications and user interfaces. Until now, mobile devices have been designed to remain in a stand-by state until the user actively turns it on in the interaction sense. The motivation for this approach has been battery conservation. Imaging is a versatile sensing modality that can enable context recognition, unobtrusively predicting the user's interaction needs and directing the computational resources accordingly. However, vision-based always-on functionalities have been impractical in battery-powered devices, since their requirements of computational power and energy make their use unattainable for extended periods of time. Vision-based applications can benefit from the addition of interactive stages that, properly designed, can reduce the complexity of the methods utilizing user feedback and collaboration, resulting in a system that balances computational throughput and energy efficiency. The usability of user interfaces critically rests on their latency. However, an always-on sensing platform needs a careful balance with the power consumption demands. Improving reactiveness when designing for highly interactive vision-based interfaces can be achieved by reducing the number of operations that the application processor needs to execute, deriving the most expensive tasks to accelerators or specific processors. In this context, this thesis focuses on investigating and surveying enablers and solutions for vision-based interactivity on mobile devices. The thesis explores the development of new user interaction methods by analyzing and comparing means to reach interactivity, high performance, low latency and energy efficiency. The researched techniques, ranging from mobile GPGPU and dedicated sensor processing to reconfigurable image processors, provide understanding on designing for future mobile platforms. / Tiivistelmä Tulevaisuuden multimodaalisten mobiilialustojen sovellusten ja käyttöliittymien odotetaan vaativan käyttäjältä läheistä vuorovaikutusta. Tähän saakka mobiililaitteet on suunniteltu pysymään valveustilassa siihen asti kunnes käyttäjä aktivoi laitteen. Tällä lähestymistavalla on pyritty pidentämään akun kestoa. Kuvantaminen on monipuolinen aistimodaliteetti, joka mahdollistaa kontekstin tunnistuksen ennakoimalla huomaamattomasti käyttäjän vuorovaikutustarpeet ja suuntaamalla laskennalliset resurssit asianmukaisesti. Näköpohjaiset, jatkuvasti päällä olevat toiminnot ovat kuitenkin epäkäytännöllisiä akkukäyttöisissä laitteissa sillä niiden laskennallisen suoritustehokkuuden ja akun keston vaatimukset tekevät pidemmästä yhtäjaksoisesta käytöstä mahdotonta. Kamerapohjaiset sovellukset voivat hyötyä interaktiivisten vaiheiden lisäämisestä. Oikein suunniteltuina ne vähentävät käyttäjäpalautetta ja -yhteistyötä hyödyntävien menetelmien monimutkaisuutta, joka saattaa laskennallisen suoritustehokkuuden ja energiatehokkuuden tasapainoon. Käyttöliittymien käytettävyys on kriittisesti riippuvainen niiden viiveestä. Jatkuvasti päällä oleva aistiva alusta edellyttää kuitenkin tasapainottelua virrankulutuksen vaatimusten kanssa. Hyvin interaktiivisia kamerapohjaisia käyttöliittymiä suunniteltaessa reaktiivisuuden parantaminen saadaan aikaan vähentämällä prosessorin käsittelemien operaatioiden määrää, johtamalla kuormittavimmat tehtävät kiihdyttimille tai erillisille prosessoreille. Tässä kontekstissa, väitöskirjatutkimus keskittyy tutkimaan ja tarkastelemaan mahdollistajia ja ratkaisuja kamerapohjaiseen vuorovaikutukseen mobiililaitteissa. Väitöskirja tutkii uusien käyttäjäinteraktiomenetelmien kehittämistä vuorovaikutusta, suoritustehoa, alhaista viivettä ja energiatehokkuutta tuottavia keinoja analysoimalla ja vertaamalla. Tutkitut tekniikat mobiilista grafiikkaprosessoreista ja erillis sensoriprosessoinnista uudelleen konfiguroitaviin kuvaprosessoreihin tuovat ymmärrystä tulevaisuuden mobiilien alustojen suunnitteluun.

Abstract Efficient management of rather limited resources, including radio spectrum and mobile-terminal battery power, has been the fundamental design challenge of wireless networks and one of the most widespread research problems over the years. MAC (Medium Access Control) for packet access and CAC (Call Admission Control) for connection-oriented service domains are commonly used as effective tools to manage radio resources, capacity and performance of wireless networks while providing adequate QoS (Quality of Service) to mobile users. Hence, analysis and synthesis of efficient MAC and CAC schemes for advanced wireless networks have significant academic and practical values. This dissertation addresses that topic and presents seven separate contributions of the author: four on adaptive MAC schemes for centralized PRN (Packet Radio Networks), referred to as SPA (Smart Packet Access) and three on CAC schemes for cellular networks, referred to as SCA (Smart Call Admission). These contributions are published in eighteen original papers by the author, which are listed and referred to as Papers I–XVIII in this thesis. In SPA, the first contribution, reported in Papers II and IV, studies implementation losses of adaptive feedback-control MAC schemes for the uplink of DS-CDMA (Direct-Sequence Code Division Multiple Access) PRN in the presence of various system imperfections. The second contribution, reported in Papers XI, XII, XV and XVI, proposes a bit-rate adaptive MAC scheme for DS-CDMA PRN, referred to as SPR (Smart Packet Rate). The third contribution, reported in Papers III, XIII and XIV, develops two alternative MAC schemes with adaptive packet-length over correlated fading channels in DS-CDMA PRN, referred to as SPL (Smart Packet Length). The fourth contribution, reported in Papers XVII and XVIII, develops alternative adaptive MAC schemes for optimal trade-offs between throughput and energy consumption of TCP (Transmission Control Protocol) applications in advanced cellular networks. These include a so-called SPD (Smart Packet Dispatching) for HSPA (High Speed Packet Access) and, again, SPL for LSPA (Low Speed Packet Access). Moving on to SCA, the first contribution, reported in Papers V and VII, provides a simple and accurate analytical method for performance evaluation of a class of fixed-assignment CAC schemes with generic guard-channel policy and queuing priority handoffs in cellular networks. The second contribution, reported in Papers VI, IX and X, proposes a simple and effective SCAC (Soft-decision CAC) scheme for CDMA cellular networks. This is evaluated against fixed-assignment and measurement-based CAC schemes with a simple and reliable method provided as a part of the contribution. The third contribution, reported in Papers I and VIII, incorporates alternative QoS differentiation paradigms and resource partitioning into CAC, defines GoS (Grade of Service) for multimedia cellular networks, and provides an in-hand tool for efficient capacity and GoS management.

Les data centers sont des infrastructures qui hébergent un grand nombre d’équipements informatiques. Plus de 99% de la puissance électrique consommée par les composants électroniques est transformée en chaleur. Pour assurer leur bon fonctionnement il est donc nécessaire de les refroidir. Cette opération est majoritairement réalisée par l’emploi de systèmes de climatisation à air très énergivores. De plus, la densité de puissance dissipée au sein des baies informatiques est en augmentation permanente. Nous arrivons alors aux limites de l’utilisation de l’air comme fluide caloporteur pour le refroidissement. Les études réalisées durant cette thèse concernent l’amélioration de l’efficacité énergétique des systèmes de refroidissement des baies électroniques par l’exploitation de liquides comme fluides caloporteurs. Cette approche permet de bénéficier de coefficients d’échanges thermiques et de capacités de refroidissement plus importants, avec des perspectives plus viables pour la revalorisation de la chaleur issue des data centers.Durant la thèse, quatre solutions de refroidissement ont été évaluées. Des expérimentations ont été menées à l’échelle de serveurs et d’une baie informatique. Une instrumentation conséquente permet de mettre en évidence le bon refroidissement des composants et de déterminer des indicateurs d’efficacité énergétique des systèmes étudiés. A partir des résultats expérimentaux, deux modèles numériques sont développés par une approche nodale et une identification des paramètres par méthode inverse. Ces modèles pourront être dupliqués à l’échelle d’une salle informatique afin de quantifier les gains potentiels de deux solutions de refroidissement liquide. / Data centers are facilities that house a large numbers of computer equipment. More than 99% of the electrical power consumed by the electronic components is converted into heat. To ensure their good working, it is necessary to keep them under their recommended temperatures. This is mainly achieved by the use of air conditioning systems which consume a lot of electrical power. In addition, the power density of computer racks is constantly increasing. So the limits of air as a coolant for electronic equipment cooling are reached.Studies conducted during this thesis concern the improvement of energy efficiency of cooling systems for electronic rack by using liquids as heat transfer fluids. This approach gives higher heat exchange coefficients and larger cooling capacity with more viable aspects for the recovering of heat from data centers.Four cooling solutions are evaluated. Experiments are conducted on several servers and on a computer rack. A consistent instrumentation helps to highlight the efficiency of components cooling and allows us to identify energy efficiency indicators of the studied systems. From the experimental results, two numerical models are developed by a nodal approach and a parameter identification by inverse method is carried out. These models can be duplicated at the scale of a data center room in order to quantify the potential gains of two liquid cooling solutions.

When speaking about energy it means speaking about life, activity, economy, growth and environmental issues. The issue of energy has been the main article all over the world in recent years, this is due to the importance of energy to life and its impact on the environment. For example, Paris climate change meeting in 2015 is one of the recent global meeting which directly related to the energy use by nations. The meeting was mainly focused up on the restriction of greenhouse gas emission which implies that industries should think about other alternative energy resources rather than fossil fuel for positive impact on climatic change. This is one of the cases that led industries into greater competition in the global market. Industries must consider energy alternatives which is safe for the environment and by using such energy a competitive product with better quality and quantity should be produced. This challenge has motivated industries to look and study the energy that they are using currently. Studies and researches show that one of the main and most abundant energy resources that most of these industries can get is by improving the energy efficiency or managing the energy that they currently use. The main aim of this thesis is to provide Arizona chemical plant (Kraton) at Sandarne on the potential energy saving by managing their energy use. The first wisdom in energy utilization is managing and using the energy they possess efficiently. In Arizona plant at Sandarne, the product named “Pitch” (a natural viscoelastic polymer or rosin) is a fuel used as the primary energy supply for the production of steam by boilers. The steam may be utilized well but the energy in the condensate (after steam loses its latent heat) is not addressed well enough. Hence this paper has studied on how significant is the energy lost by the steam condensate is and how its recovery can be used to save energy and cost. The plant produces about an average of 11.42 ton of steam each hour in a year. This steam can be returned or fully recovered (100%) as condensate from the law of conservation of mass since only energy is lost from the steam. But the plant returns a maximum of about 3ton of condensate each hour. This amount is relatively low compared to the amount of condensate recovery possibility. Recovery possibility of condensate return showed that the plant at Sandarne can return at least 8.5 ton of condensate  each hour. In comparison with the current return estimated 5.5 ton of condensate is being lost simply as waste each hour leading to about 400 SEK minimum cost loss. The calculation of cost is in minimum because the charge from water supply and condensate effluent disposal charge are not considered. In this paper only recovery from the easily recoverable steam condensate is being considered (25% of the system) which resulted in payback time of the proposed investment 1.88 years without considering the above explained charges. It is much motivating study considering the generalized approach and over simplified method. If a deeper investigation is made on the potential, it can be clearly shown that how significant the potential is in securing and sustaining energy and environmental issues. Ensuring the security and sustainability of energy which addresses the environmental issue precisely will help the plant to stay on the race of global market competition.   Keywords: Energy efficiency, Boiler efficiency, Energy management, Condensate recovery,

Please read the abstract in the section 00front of this document / Thesis (PhD (Mechanical Engineering))--University of Pretoria, 2007. / Mechanical and Aeronautical Engineering / unrestricted

This dissertation presents several novel accomplishments in the research area of Wireless Body Area Networks (WBANs), including in vivo channel characterization, optimization and game theoretical approaches for energy efficiency in WBANs. First, we performed the in vivo path loss simulations with HFSS human body model, built a phenomenological model for the distance and frequency dependent path loss, and also investigated angle dependent path loss of the in vivo wireless channel. Simulation data is produced in the range of 0.4−6 GHz for frequency, a wide range of distance and different angles. Based on the measurements, we produce mathematical models for in body, on body and out of body regions. The results show that our proposed models fit well with the simulated data. Based on our research, a comparison of in vivo and ex vivo channels is summarized. Next, we proposed two algorithms for energy efficiency optimization in WBANs and evaluated their performance. In the next generation wireless networks, where devices and sensors are heterogeneous and coexist in the same geographical area creating possible collisions and interference to each other, the battery power needs to be efficiently used. The first algorithm, Cross-Layer Optimization for Energy Efficiency (CLOEE), enables us to carry out a cross-layer resource allocation that addresses the rate and reliability trade-off in the PHY, as well as the frame size optimization and transmission efficiency for the MAC layer. The second algorithm, Energy Efficiency Optimization of Channel Access Probabilities (EECAP), studies the case where the nodes access the medium in a probabilistic manner and jointly determines the optimal access probability and payload frame size for each node. These two algorithms address the problem from an optimization perspective and they are both computationally efficient and extensible to 5G/IoT networks. Finally, in order to switch from a centralized method to a distributed optimization method, we study the energy efficiency optimization problem from a game theoretical point of view. We created a game theoretical model for energy efficiency in WBANs and investigated its best response and Nash Equilibrium of the single stage, non-cooperative game. Our results show that cooperation is necessary for efficiency of the entire system. Then we used two approaches, Correlated Equilibrium and Repeated Game, to improve the overall efficiency and enable some level of cooperation in the game.