Thèses : « Evaluation of energy consumption »

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Arokiasamy, David Balachandar. « Energy Consumption Evaluation of LoRa Technology ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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Lora is a wireless technology that has been developed to enable low data rate communications to be made over long distances especially for IoT applications. With growing Internet of things, Lora technology addresses the increasing demands on end devices for long range connectivity with low power battery consumption and also with low infrastructure cost to deploy. Lora utilizes a spread spectrum modulation and protocol in Sub-Ghz RF band to enable long range greater than 10 km with low power and high network capacity. In this thesis, I would like to give some comprehensive introduction about Lora specifications. As we know that Lora consumes low power to transmit the data packets given to the physical layer and the query is to know in which range of low power lies. This will be the outcome of my thesis with energy measurements for transmitting a data packet. This also includes different configurations of the devices.

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Osqui, Mitra M. 1980. « Evaluation of software energy consumption on microprocessors ». Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8344.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2002.
Includes bibliographical references (leaves 72-75).
In the area of wireless communications, energy consumption is the key design consideration. Significant effort has been placed in optimizing hardware for energy efficiency, while relatively less emphasis has been placed on software energy reduction. For overall energy efficiency reduction of system energy consumption in both hardware and software must be addressed. One goal of this research is to evaluate the factors that affect software energy efficiency and identify techniques that can be employed to produce energy optimal software. In order to present a strong argument, two state-of-the-art low power processors were used for evaluation: the Intel StrongARM SA-1100 and the next generation Intel Xscale processor. A key step in analyzing the performance of software is to perform a comprehensive tabulation of the energy consumption per instruction, while taking into account the different modes of operation. This leads into a comprehensive energy profiling for the instruction set of the processors of interest. With information on the energy consumption per instruction, we can evaluate the feasibility of energy efficient programming and use the results to gain greater insight into the power consumption of the two processors under consideration. Benchmark programs will be tested on both processors to illustrate the effectiveness of the energy profiling results. The next goal is to look at the leakage current and current consumed during idle modes of the processors and how that impacts the overall picture of energy consumption. Thus energy consumption will be explored for the two processors from both a dynamic and static energy consumption perspective.
by Mitra M. Osqui.
S.M.

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Damron, Lauren Leigh Brannom. « An energy consumption evaluation for existing, commercial buildings ». Kansas State University, 2017. http://hdl.handle.net/2097/38228.

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Master of Science
Department of Architectural Engineering and Construction Science
Julia A. Keen
The intent of this report is to recommend a process for legislation that can be used to identify commercial buildings that have the greatest potential to reduce energy consumption. A point-based evaluation is completed of current energy processes for existing commercial buildings. The recommended energy evaluation system is applied to an existing building, which allows for a detailed review of how the evaluation is completed for a building. The results are presented to display the value of assessing building energy performance. Additionally, the results reinforce the potential to transform the industry and energy use by buildings.

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Armstrong, Stephen George. « Thermal evaluation of building detail ». Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387382.

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Vuppuluri, Prem Kiran. « Impact of Sustainable Cool Roof Technology on Building Energy Consumption ». PDXScholar, 2014. http://pdxscholar.library.pdx.edu/open_access_etds/1530.

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Highly reflective roofing systems have been analyzed over several decades to evaluate their ability to meet sustainability goals, including reducing building energy consumption and mitigating the urban heat island. Studies have isolated and evaluated the effects of climate, surface reflectivity, and roof insulation on energy savings, thermal load mitigation and also ameliorating the urban heat island. Other sustainable roofing systems, like green-roofs and solar panels have been similarly evaluated. The motivation for the present study is twofold: the first goal is to present a method for simultaneous evaluation and inter-comparison of multiple roofing systems, and the second goal is to quantitatively evaluate the realized heating and cooling energy savings associated with a white roof system compared to the reduction in roof-top heat flux. To address the first research goal a field experiment was conducted at the International Harvester Building located in Portland, OR. Thermal data was collected for a white roof, vegetated roof, and a solar panel shaded vegetated roof, and the heat flux through these roofing systems was compared against a control patch of conventional dark roof membrane. The second research goal was accomplished using a building energy simulation program to determine the impact of roof area and roof insulation on the savings from a white roof, in both Portland and Phoenix. The ratio of cooling energy savings to roof heat flux reduction from replacing a dark roof with a white roof was 1:4 for the month of July, and 1:5 annually in Portland. The COP of the associated chillers ranges from 2.8-4.2, indicating that the ratio of cooling energy savings to heat flux reduction is not accounted for solely by the COP of the chillers. The results of the building simulation indicate that based on energy savings alone, white roofs are not an optimal choice for Portland. The benefits associated with cooling energy savings relative to a black roof are offset by the winter-time penalty, and the net benefit from adopting white roof technology in Portland is small. That said, there are other potential benefits of white roofing such as impact on urban heat islands and roof life that must also be considered.

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Sanaboyina, Tulasi Priyanka. « Performance Evaluation of Time series Databases based on Energy Consumption ». Thesis, Blekinge Tekniska Högskola, Institutionen för kommunikationssystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13593.

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The vision of the future Internet of Things is posing new challenges due to gigabytes of data being generated everyday by millions of sensors, actuators, RFID tags, and other devices. As the volume of data is growing dramatically, so is the demand for performance enhancement. When it comes to this big data problem, much attention has been given to cloud computing and virtualization for their almost unlimited resource capacity, ﬂexible resource allocation and management, and distributed processing ability that promise high scalability and availability. On the other hand, the variety of types and nature of data is continuously increasing. Almost without exception, data centers supporting cloud based services are monitored for performance and security and the resulting monitoring data needs to be stored somewhere. Similarly, billions of sensors that are scattered throughout the world are pumping out huge amount of data, which is handled by a database. Typically, the monitoring data consists time series, that is numbers indexed by time. To handle this type of time series data a distributed time series database is needed. Nowadays, many database systems are available but it is difficult to use them for storing and managing large volumes of time series data. Monitoring large amounts of periodic data would be better done using a database optimized for storing time series data. The traditional and dominant relational database systems have been questioned whether they can still be the best choice for current systems with all the new requirements. Choosing an appropriate database for storing huge amounts of time series data is not trivial as one must take into account diﬀerent aspects such as manageability, scalability and extensibility. During the last years NoSQL databases have been developed to address the needs of tremendous performance, reliability and horizontal scalability. NoSQL time series databases (TSDBs) have risen to combine valuable NoSQL properties with characteristics of time series data from a variety of use-cases. In the same way that performance has been central to systems evaluation, energy-efﬁciency is quickly growing in importance for minimizing IT costs. In this thesis, we compared the performance of two NoSQL distributed time series databases, OpenTSDB and InﬂuxDB, based on the energy consumed by them in different scenarios, using the same set of machines and the same data. We evaluated the amount of energy consumed by each database on single host and multiple hosts, as the databases compared are distributed time series databases. Individual analysis and comparative analysis is done between the databases. In this report we present the results of this study and the performance of these databases based on energy consumption.

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Sakva, Denys. « Evaluation of errors in national energy forecasts / ». Link to online version, 2005. https://ritdml.rit.edu/dspace/handle/1850/1166.

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Vahdati, Maria Malahat. « Evaluation of a two fluid ejector-compressor applicable to a domestic heat pump ». Thesis, University of Bristol, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295657.

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Hashim, Nizar Hessain. « Evaluation of alternative thermal strategies for the precast concrete system houses in Jeddah, Saudi Arabia ». Thesis, Cardiff University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358781.

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Westin, Jonathan. « Evaluation of energy consumption in virtualization environments : Proof of concept using containers ». Thesis, Umeå universitet, Institutionen för datavetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-142550.

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The demand for cloud services offering virtualization increases with a continual interest for different types of applications. Regardless of the resource demand of the application, some supplier is billing by the time of usage, making it an unfair pricing for the clients. In this thesis, the virtualization characterization and properties make room for another form of payment qualities. Since power consumption is comprehensible and an understandable measurement for both parties it is investigated if there are any useful ways of measuring energy consumption of an application. The thesis creates a proof of concept of predicting energy consumption from CPU usage from a containerized application. With an empirical simulation and the use of linear regression, the results are feasible of estimating the energy consumption from the simulation data with a 0.813 Watt deviation. Even though the proof of concept is a harsh simplification of the dilemma for predicting energy consumption from an application, the thesis embraces the issue of energy consumption within data centers.

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Crespo, Raul Jose. « Evaluation of energy usage in the chemical industry and effective measures to reduce energy losses ». Master's thesis, Mississippi State : Mississippi State University, 2009. http://library.msstate.edu/etd/show.asp?etd=etd-04022009-173317.

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Mangasarian, Seth. « Energy consumption evaluation of United States Navy LEED certified buildings for fiscal year 2009 ». Thesis, University of Wisconsin-Madison, 2010. http://hdl.handle.net/10945/4940.

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CIVINS
Approved for public release; distribution is unlimited
As of October 1, 2008, the Department of the Navy inserted the requirement that all new buildings constructed for the United States Navy and United States Marine Corps would have an additional requirement to become Leadership in Energy and Environmental Design (LEED) Silver certified by the United States Green Building Council (USGBC). The goal of this effort is in compliance with Executive Order (EO) 13423, which provides that all Government departments must reduce energy consumption by 30% by 2015. The objective of this research is to find if the eleven buildings for the United States Navy that have already received a LEED certification or higher, have achieved the expected energy consumption savings in comparison to other similar non-LEED certified facilities. To accomplish this effort, these buildings have been compared to other United States Navy and Marine Corps commercial buildings of comparable size, usage, and within the same region as chosen by the respective Public Works Departments. The data being compared for this study will be electricity and water consumption, based upon what could be received from the current building's meters. Additionally, these LEED certified buildings will be compared to the national averages for electricity consumption as expressed by the Commercial Building Energy Consumption Survey (CBECS) to find if any energy savings is achieved to buildings of similar size.

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Toussaint, Wiebke. « Evaluation of clustering techniques for generating household energy consumption patterns in a developing country ». Master's thesis, Faculty of Science, 2019. http://hdl.handle.net/11427/30905.

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This work compares and evaluates clustering techniques for generating representative daily load profiles that are characteristic of residential energy consumers in South Africa. The input data captures two decades of metered household consumption, covering 14 945 household years and 3 295 848 daily load patterns of a population with high variability across temporal, geographic, social and economic dimensions. Different algorithms, normalisation and pre-binning techniques are evaluated to determine the best clustering structure. The study shows that normalisation is essential for producing good clusters. Specifically, unit norm produces more usable and more expressive clusters than the zero-one scaler, which is the most common method of normalisation used in the domain. While pre-binning improves clustering results for the dataset, the choice of pre-binning method does not significantly impact the quality of clusters produced. Data representation and especially the inclusion or removal of zero-valued profiles is an important consideration in relation to the pre-binning approach selected. Like several previous studies, the k-means algorithm produces the best results. Introducing a qualitative evaluation framework facilitated the evaluation process and helped identify a top clustering structure that is significantly more useable than those that would have been selected based on quantitative metrics alone. The approach demonstrates how explicitly defined qualitative evaluation measures can aid in selecting a clustering structure that is more likely to have real world application. To our knowledge this is the first work that uses cluster analysis to generate customer archetypes from representative daily load profiles in a highly variable, developing country context

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Cosar-Jorda, Paula. « A socio-technical evaluation of the impact of energy demand reduction measures in family homes ». Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/25181.

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Energy consumption in the home depends on appliance ownership and use, space heating systems, control set-points and hot water use. It represents a significant proportion of national demand in the UK. The factors that drive the level of consumption are a complex and interrelated mix of the numbers of people in the home, the building and system characteristics as well as the preferences for the internal environment and service choices of occupants. Reducing the energy demand in the domestic sector is critical to achieving the national 2050 carbon targets, as upward of 60% reduction in demand is assumed by many energy system scenarios and technology pathways. The uptake of reduction measures has been demonstrated to be quite ad hoc and intervention studies have demonstrated considerable variation in the results. Additionally, a limitation of many studies is that they only consider one intervention, whereas a more holistic approach to the assessment of the potential of reduction measures in specific homes may yield a better understanding of the likely impact of measures on the whole house consumption and indeed would shed light on the appropriateness of the assumptions that underpin the decisions that need to be made regarding the future energy supply system and demand strategies. This work presents a systematic approach to modelling potential reductions for a set of seven family homes, feeding back this information to householders and then evaluating the likely reduction potential based on their responses. Carried out through a combination of monitoring and semi-structured interviews, the approach develops a methodology to model energy reduction in specific homes using monitoring data and steady-state heat balance principles to determine ventilation heat loss, improving the assumptions within the energy model regarding those variables affected by human behaviour. The findings suggest that the anticipated reductions in end use energy demand in the domestic sector are possible, but that there is no `one size fits all' solution. A combination of retrofitting and lifestyle change is needed in most homes and smart home technology may potentially be useful in assisting the home owner to achieve reductions where they are attempting to strike a balance between energy efficiency, service and comfort.

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Bhattacharjee, Suchismita. « Analytical Framework to Study Energy Efficiency Policy Portfolios across Countries/States ». Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/28386.

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Energy conservation and implementation of effective energy efficiency policies have become imperative to curbing the escalating consumption of energy. The imbalance in the supply and demand of a country's energy has increased the importance of implementing energy efficiency policies. Proper replication of strategic energy efficiency policies that are known to be successful in one country, along with development of new approaches, can be helpful in developing the energy policy portfolio of another country. Some OECD (Organization of Economic Cooperation and Development) countries like Denmark, Finland, France, Germany, Italy, the United Kingdom and the United States have benefited from their energy policies during the most recent energy crisis. The motivation of this research is to provide a tool for developing countries, which are still in the stage of formulating their energy efficiency policies, to compare energy efficiency policy portfolios across countries. These countries can improve their energy efficiency policy portfolios based on lessons learned from the developed countries. The research develops a framework to compare energy efficiency policy portfolios across countries / states. Although this framework can be adopted for any type of energy policy, targeting any sector with few modifications, the current focus is on policies that target the residential building sector to reduce energy consumption. The research begins with identification of the functional domains that influence human behavior–people, economy, environment and technology–followed by identification of the factors affecting household energy consumption. It uses the four functional domains as the evaluation framework's four axes. The various factors affecting household energy consumption are positioned in the framework based on association with the functional domains. The energy efficiency policies implemented in a country are positioned in the same framework based on the pattern of diffusion of each type of policy. In addition, a prototype method is developed to identify the factors targeted by each energy efficiency policy implemented in a country. This evaluation method allows for a uniform assessment process of how energy efficiency policies target specific socio-economic factors that are known to affect energy consumption. The proposed framework will facilitate the work of policy makers and other decision makers with a powerful tool for evaluating and comparing their individual policies, or their complete portfolio of energy efficiency policies, to those from other states or countries, and to benefit from the lessons learned.
Ph. D.

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Vemula, Bhanoday Reddy. « Evaluation of robot structures : For applications that require high performance, safety and low energy consumption ». Licentiate thesis, Mälardalens högskola, Innovation och produktrealisering, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-29307.

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Emerging application areas, such as safe robotics and green robotics, greatly enable the extension of robot automation to new application processes in different industry segments. Successful realization of industrial robots for such application areas is highly influenced by the type of robot structure that is adopted for the design. Therefore, researchers have recently pursued new robot structures with improved characteristics resulting in the current availability of a wide variety of potential robot structures from which to choose. Along with this, a difficult yet relevant challenge arises for robot designers to evaluate all the potential robot structures to select the best structure for new applications. This necessitates a need for tools or methods, which can aid robot designers or end-users to perform evaluation on robot structures in the early design stages. The research objective pursued in this thesis aims to address this need. To realize this objective, design knowledge must be advanced on ways or methods to quantitatively evaluate robot structures. This project adopts research through design as a research methodology, which is based on the action-reflection approach. In this thesis, experiential knowledge is gained on how to evaluate a set of two robot structures based on various requirements. This is done by carrying out simulation-based evaluation tasks on serial and parallelogram linkage articulated robot structures. Based on the acquired experiential knowledge, a simulation-based evaluation framework is proposed in this thesis, which can be used by robot designers or end-users to enhance the likelihood of selecting the most suitable robot structure for a new application process.

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Granberg, Niklas, et Anna Pestrea. « Evaluating mobile communication energy consumption with video and voice communication ». Thesis, Linköpings universitet, Institutionen för datavetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-150391.

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Today smart phones can be used in different ways for different scenarios. One is video and voice calls over internet, which consumes a lot of energy and could be improved. This thesis studies how different wireless communication technologies affect the battery consumption of a mobile device. This is measured with the help of a software program named EnergyBox. By capturing different traces on a smartphone and giving it as input to Energybox, we can see how different communication methods affect the energy consumption. These results showed that voice calls consumed less energy than video calls and that WiFi was the most energy efﬁcient transmission technology, followed by 3G and LTE. It could also be seen that if the call interval was shortened for the video calls the energy consumption decreased. 3G also showed some interesting results that should be investigated further. The conclusion of this is that voice calls are preferred over video calls considering the energy aspect and that WiFi consumes less energy than 3G, which consumes less than LTE.

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Weigel, Brent Anthony. « Development of a commercial building/site evaluation framework for minimizing energy consumption and greenhouse gas emissions of transportation and building systems ». Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44735.

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In urbanized areas, building and transportation systems generally comprise the majority of greenhouse gas (GHG) emissions and energy consumption. Realization of global environmental sustainability depends upon efficiency improvements of building and transportation systems in the built environment. The selection of efficient buildings and locations can help to improve the efficient utilization of transportation and building systems. Green building design and rating frameworks provide some guidance and incentive for the development of more efficient building and transportation systems. However, current frameworks are based primarily on prescriptive, component standards, rather than performance-based, whole-building evaluations. This research develops a commercial building/site evaluation framework for the minimization of GHG emissions and energy consumption of transportation and building systems through building/site selection. The framework examines, under uncertainty, multiple dimensions of building/site operation efficiencies: transportation access to/from a building site; heating, ventilation, air conditioning, and domestic hot water; interior and exterior lighting; occupant conveyances; and energy supply. With respect to transportation systems, the framework leverages regional travel demand model data to estimate the activity associated with home-based work and non-home-based work trips. A Monte Carlo simulation approach is used to quantify the dispersion in the estimated trip distances, travel times, and mode choice. The travel activity estimates are linked with a variety of existing calculation resources for quantifying energy consumption and GHG emissions. With respect to building systems, the framework utilizes a building energy simulation approach to estimate energy consumption and GHG emissions. The building system calculation procedures include a sensitivity analysis and Monte Carlo analysis to account for the impacts of input parameter uncertainty on estimated building performance. The framework incorporates a life cycle approach to performance evaluation, thereby incorporating functional units of building/site performance (e.g energy use intensity). The evaluation framework is applied to four case studies of commercial office development in the Atlanta, GA metropolitan region that represent a potential range of building/site alternatives for a 100-employee firm in an urbanized area. The research results indicate that whole-building energy and GHG emissions are sensitive to building/site location, and that site-related transportation is the major determinant of performance. The framework and findings may be used to support the development of quantitative performance evaluations for building/site selection in green building rating systems and other efficiency incentive programs designed to encourage more efficient utilization and development of the built environment.

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Brejon, Paul. « Les logiciels d'energetique des batiments : developpement, evaluation technique, illustrations ». Paris, ENMP, 1988. http://www.theses.fr/1988ENMP0110.

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ALVES, RICARDO BOMFIM. « ENERGY AND POPULAR CONDOMINIUM : AN EVALUATION, FROM THE PERSPECTIVE OF ENERGY CONSUMPTION, OF THE GROWTH ACCELERATION PROGRAM - PAC DO MORRO DO PREVENTÓRIO ». PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33916@1.

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A pesquisa analisou as condições do acesso à energia elétrica dos apartamentos construídos pelo Programa de Aceleração do Crescimento - PAC, cinco anos após sua inauguração no Morro do Preventório, em Niterói. A remoção de pessoas em condições de risco de deslizamentos, foi a tônica do projeto, que realocou 248 famílias em três conjuntos construídos na mesma localidade, um caso particular pela alta valorização imobiliária do entorno. Tal cenário, ao menos temporariamente, regularizou o fornecimento de energia no conjunto habitacional. Os detalhamentos quantitativos e qualitativos das questões gerais que envolvem as irregularidades na medição (gatos), tornam claras as influências práticas e simbólicas sobre a regularização do fornecimento que levaram a novas (e antigas) estratégias de consumo. Além disso, permitem também a compreensão do impacto das perdas sobre a distribuição. Para abordar a questão da eletrificação das favelas, foi realizado um paralelo entre a pobreza energética e as consequências da concentração da energia em diferentes períodos históricos e, no próprio caso brasileiro. Ao final, o estudo tece apontamentos para melhores desenhos de políticas públicas habitacionais e de eficiência energética para a população de baixa renda nos condomínios populares.
The proximity with the first decade after the beginning of the work of Programa de Aceleração do Crescimento - PAC (Growth Acceleration Program) in Preventório and around six years of the occupation of the apartments, represent an opportunity for academic investigation to value if there was an integral success of one of the main Brazilian housing policy, focusing on the perspective of regularization of electric energy consumption. With the high housing deficit and the state solving part of the demand, the public services concessionaires observe a great opportunity to reduce their non-technical losses, specifically in the case of the energy distributors, improving the design of the supplying and their measuring form, for example. However, this factor generates an increase of the resident s fixed expenses, ergo, new possibilities to return to informality. Accordingly to this, the perspective of alteration of the territory generated by the state in this locality, by the construction of 248 popular apartments to resettle families who used to live up on the hill, in the mudslide risk area, turns out as an important parameter to the configuration of different social actors with the urban space. Still for terms of comparison of the thematic range, according to the Instituto Brasileiro de Geografia e Estatística - IBGE (Brazilian Institute of Geography and Statistics), about 16 percent of the population of Niterói, where is located the Preventório s hill, inhabit in subnormal agglomerates. Thus, the main objective of the present research is to analyze the consequences of the PAC, applied in Preventório, especially regarding to the relations between the residents, their consumption and payment of electrical energy in the new residences. In face of that, were elaborated relations between the growth or not in energy losses and the decreasing of the cobrabilidade. Remaining in this aspect, the behavior of the consumers were also segmented, by the ones that received the energy efficiency actions and the ones that did not.

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Heidari, Ramin. « Android Elastic Service Execution and Evaluation ». Thesis, Blekinge Tekniska Högskola, Institutionen för programvaruteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5237.

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Context. Mobile devices recently have attained huge popularity in people’s life. During recent years, there have been many attempts for proposing several approaches to delegate and execute the computing intensive part of the mobile applications on more powerful remote servers due to shortage of resources on mobile devices. However, there are still research challenges in this area regarding the models as well as principles that govern circumstances of executing a part of mobile application remotely on a server along with effects of execution on the smartphone resources. Objectives. The aim behind conducting this research is to propose a model for executing the service component of an Android application on the remote server. This study exploits the enhancement of Android operating system functionality to execute services components on a remote powerful machine. It reports the model as well as the enhancements to achieve this purpose. Additionally, an experiment is conducted to realize what factors rule to execute a computation locally on mobile device or offload it to be executed on a remote machine. Methods. Two research methodologies have been used in preforming this research; Case study and controlled experiment. In the case study we investigates feasibility of functionality enhancement in Android operating system to run service components of Android applications on a remote server. We propose a new model for this purpose and motivate it by several different resources such as journal and conference papers and the Android developer site. A prototype of the model is implemented in order to put into use in the next part of our study. Second, a controlled experiment is conducted on the outcome prototype of the case study to explore the principles that governs executing the service component of Android application on a remote powerful machines and the affection of this execution on the mobile resources. Results. A Model for executing the service component of Android application on a powerful remote server is proposed. Also, a prototype implemented according to the Model. The effects of executing Android service components in a remote machine on energy consumption as well as performance of a smartphone are investigated. Moreover, we examined when would be beneficial to offload an intensive computation in order to be executed on the remote server. Conclusions. We conclude that it’s applicable to enhance the Android OS to execute service component of an Android application on a remote server. Also, We conclude that there is a strong coloration between amount of payload and computation of data that require to be executed on a remote server. Basically, offloading the computation is beneficial when there is a large amount of computation with small amount of communication and payload. Furthermore we conclude that the execution time for the intensive computations drastically increase when it’s executed on the server but for less computation data the performance is better when the execution is on the smartphone. Besides that, we express that the energy consumption on the smartphone growth gradually when the payload passes over a particular size.

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Lambrechts, Rhynhardt. « A performance and energy evaluation of a fertiliser-drawn forward osmosis (FDFO) system ». Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2747.

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Thesis (Master of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2018.
Globally, water is considered an essential resource as it sustains human, animal and plant life. Water is not only essential for all forms of life but imperative for economic growth. The world’s population is increasing at a disquieting rate, which will result in an increased demand for fresh water and food security. The agricultural industry is the main consumer of global freshwater and utilises fertilisers in order to meet food demands. The demand for water in South Africa (SA) has increased considerably due to the rapid expansion of the agricultural industry, and of the municipal and industrial sectors. Agricultural developments in SA are affected greatly as the country is facing a current drought crisis as a result of low rainfall and large water demands. With an abundance of saline water globally, desalinisation will be a major contributor to solving the global freshwater crisis. With limited fresh water resources accompanied by the agricultural industry as a major consumer, alternative measures are required to desalinate water specifically for agricultural use. Forward osmosis (FO) is a membrane technology that gained interest over the past decade because it has several advantages over pressure-driven membrane processes such as reverse osmosis (RO). FO technology is based on the natural osmotic process which is driven by a concentration gradient between two solutions separated by a semi-permeable membrane. Naturally, water will permeate through the membrane from a solution of low solute concentration or low osmotic pressure (OP) known as a feed solution (FS) to a solution of a higher concentration or higher OP also known as a draw solution (DS). Whilst various research studies have contributed to several advances in FO, several process limitations such as reverse solute flux (RSF), concentration polarisation (CP) and membrane fouling remain problematic, hindering FO for large-scale applications. Further investigation is therefore warranted and crucial in order to understand how to mitigate these limitations to develop/improve future processes. The aim of this study was to evaluate a fertiliser-drawn forward osmosis (FDFO) system by investigating the effects of membrane orientation, system flow rate, DS concentration, and membrane fouling on an FDFO systems performance and energy consumption. The FS used was synthetic brackish water with a sodium chloride (NaCl) content of 5 g/L whereas a potassium chloride (KCl) synthetic fertiliser was used as a DS. The membrane utilised was a cellulose triacetate (CTA) membrane and was tested in forward osmosis mode (FO mode) and pressure retarded osmosis mode (PRO mode) whilst the system flow rate was adjusted between 100, 200 and 400 mL/min. Additionally, the DS concentration was altered from 0.5, 1 and 2 M KCl, respectively. Experiments were performed using a bench scale FO setup which comprised of an i) FO membrane cell, ii) a double head variable peristaltic pump for transporting FS and DS’s respectively, iii) a digital scale to measure the mass of the DS, iv) a magnetic stirrer to agitate the FS, v) two reservoirs for the FS and DS, respectively, vi) a digital multiparameter meter to determine FS electrical conductivity (EC) and vii) a digital electrical multimeter to measure system energy consumption. Each experiment comprised of seven steps i) pre-FDFO membrane control, ii) membrane cleaning, iii) FDFO experiment, iv) post-FDFO membrane control, v) membrane cleaning, vi) membrane damage dye identification and vii) membrane cleaning. Pre- and post-FDFO membrane control experiments operated for 5 h whilst each membrane cleaning procedure operated for 30 min. The FDFO experiment operated for 24 h whilst the membrane damage dye identification operated until a minimum of 10 mL water was recovered. The process parameter which largely contributed to a beneficial system performance and specific energy consumption (SEC) was the increase in DS concentration. Water fluxes increased approximately threefold from a DS concentration increase from 0.5 to 1 M, followed by an additional 30 to 50 % rise in water flux at a DS concentration increase 1 to 2 M. SEC decreased by 58 and 53 % for FO and PRO modes, respectively, with a DS concentration increase from 0.5 to 1 M. An additional 35 and 37 % SEC reduction for FO and PRO modes was obtained for a DS concentration increase from 1 to 2 M. Altering the membrane from FO to PRO did not contribute to a beneficial system performance nor did it improve SEC. However, at a DS concentration of 0,5 M, the PRO mode obtained a 5.3 % greater water recovery compared to the FO mode. Conversely, at a DS concentration of 1 and 2 M, the FO mode achieved 5.4 and 7.0 % greater water recoveries compared to the PRO mode. The increase in flow rate also did not increase system performance significantly, however, a fluctuation in system SEC was observed. Throughout the study, no membrane fouling was observed, however, possible minute traces of membrane fouling could be observed from the membrane surface electron microscope (SEM) images. Additionally, minor changes in post- FDFO membrane control water recovery results were noticed which support the possible occurrence of membrane fouling during the FDFO experiment.

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Шийко, В. І. « Оцінювання енерговитрат газотранспортних підприємств ». Thesis, Івано-Франківський національний технічний університет нафти і газу, 2013. http://elar.nung.edu.ua/handle/123456789/1755.

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Дисертацію присвячено дослідженню теоретичних, методичних та прикладних аспектів проблеми оцінювання енерговитрат на підприємствах магістрального транспортування природного газу. У роботі досліджено проблему енергозбереження України і газотранспортної галузі, класифіковано програми енергозбереження, визначено та систематизовано основні джерела фінансування енергоощадних заходів, здійснено аналіз генезису ідей і принципів щодо понять «енерговитрати» та «енергозбереження», визначено їх економічну суть, розроблено методичний підхід до оцінювання енерговитратності при транспортуванні природного газу, проаналізовано нормативно-правове забезпечення діяльності газотранспортної галузі та процесу енергозбереження в ній та надані рекомендації щодо її покращення. Вдосконалено класифікацію факторів впливу на енерговитратиість газотранспортної системи України, проведено аналіз енергоспоживання на її підприємствах, удосконалено систему оцінювання та управління енерговитратами виробництва. Запропоновано нові підходи до створення програм енергозбереження, здійснено оцінку енерговитратності технології трубопровідного транспортування природного газу, побудовано модель коефіцієнта енергомісткості і на її основі зроблено оптимізацію енерговитрат.
Theoretical, methodical and practical aspects of expenditure energy problem are considered in the thesis. The energy saving programs are classified. The main sources of funding energy-saving measures are identified and systematized. Analyzed the genesis of ideas and principles concerning the concepts of «costs energy» and «saving energy», defined their economic substance. The method of evaluating energy consumption in the pipeline companies is developed. Recommendations for improving the regulatory and legal framework was provided for saving energy in pipeline companies. Classification of factors of influence on energy consumption was improved in the gas transportation system of Ukraine. Investigated and evaluated energy consumption in the pipeline companies. The system of assessment and management of energy consumption was improved. New approaches to the creation of energy efficiency programs was offered. The energy consumption was estimated technologies of pipelines transportation of natural gas. The coefficient of energy consumption was modeled and use it to optimized energy consumption.

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Rahman, Mohammed. « A performance and energy evaluation of a dye drawn forward osmosis (FO) system for the textile industry ». Thesis, Cape Peninsula University of Technology, 2020. http://hdl.handle.net/20.500.11838/3068.

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Thesis (MEng (Chemical Engineering))--Cape Peninsula University of Technology, 2020
Continuous growth in the world population has raised significant fears with regards to the sustainability of energy and water resources. Globally, water is an indispensable resource as it is essential for the sustenance of human, animal and plant life. Water is essential for all forms of life and plays a pivotal role in economic growth. The textile industry is one of the greatest consumers of water, it is, therefore, necessary to effectively treat the large amounts of wastewater before discharge to the environment. It is estimated that annually, more than 700,000-tonnes of textile wastewater is produced by the dyeing industry. Textile wastewater is generally characterised by electrolytes, suspended solids, mineral oils and multiple textile dyes, and has therefore been classified as one of the most polluting wastewaters. These dyes are toxic and, in most cases, are not biodegradable. The presence of very small amounts (i.e. < 1 ppm) of dyes in water has aesthetic impacts and is thus undesirable. It is, therefore, necessary to treat textile wastewater before discharging. Currently, membrane technology is widely used for wastewater treatment, as well as water purification. Forward osmosis (FO) is a promising technology for both these applications. FO is characterised by the flow of water through a semipermeable membrane from a feed solution (FS) characterised by the low solute concentration or low osmotic pressure (OP) to a draw solution (DS) characterised by the high solute concentration or high OP, due to the OP gradient across the membrane. The FO process eliminates the need for high hydraulic pressure, as required in traditional membrane technologies, and also has low fouling tendencies. Furthermore, FO has the advantage of lower energy requirements and membrane replacement costs. However, there are still many disadvantages such as reverse solute flux (RSF), membrane fouling, and concentration polarisation (CP) amongst others that still need to be addressed. Therefore, more research needs to be done in light of these limitations to better understand and mitigate these limitations to increase the effectiveness and efficiency of the FO process. This study aimed to evaluate a dye-driven FO system for the reclamation of water from textile wastewater and synthetic brackish water (BW5) by investigating the effects of membrane orientation, system flowrate, change in DS, and membrane fouling on the FO systems performance and energy consumption. The FS used was BW5 with sodium chloride (NaCl) content of 5 g/L whereas Reactive Black 5 (i.e. a reactive dye) and Maxilon Blue GRL (i.e. a basic dye) dyes were used as a DS, respectively. The membrane utilised was a cellulose triacetate (CTA) membrane and was tested in FO mode and pressure retarded osmosis (PRO) mode whilst the system flowrate was adjusted to 400, 500 and 600 mL/min, respectively. Experiments were performed using a bench-scale FO setup which comprised of an FO membrane cell, a double-head variable speed peristaltic pump, a digital scale, two reservoirs for the FS and DS, respectively, a digital multiparameter meter and a digital electrical multimeter to measure system energy consumption. Each experiment comprised of six steps: baseline 1 (membrane control), main experiment (dye-driven FO experiment), baseline 2 (membrane control repeat), membrane cleaning, membrane integrity (membrane damage dye identification) and membrane cleaning (preparation for next experiment). The baseline 1 and baseline 2 experiments operated for 3 h whilst each membrane cleaning procedure operated for 30 min. The main experiments operated for 5 h in the FO mode and 4 h in PRO mode whilst the membrane integrity experiments operated until a minimum of 10 mL water was recovered. Results showed that the PRO mode achieved both higher forward flux (𝐽𝑤) (i.e. 8.87, 8.71 and 9.13 L/m2.h for flowrates of 400, 500 and 600 ml/min) and water recovery (𝑅𝑒) rates compared to FO mode (i.e. 6.60, 6.88 and 7.58 L/m2.h for flowrates of 400, 500 and 600 ml/min). The variation of flowrates had little to no influence on the 𝐽𝑤, 𝐽𝑠 and 𝑅𝑒 of the system. The system consumed less energy in PRO mode (i.e. 381 kWh/m3 average consumption for all three flowrates) than FO mode (i.e. 417 kWh/m3 average consumption for all three flowrates). It was also observed that at a higher DS 𝑂𝑃, the system consumed less energy. Therefore, selecting an optimum initial 𝑂𝑃 is essential for a FO process to minimise the pumping energy. Furthermore, a change in DS from Reactive Black 5 dye to Maxilon Blue GRL dye had no significant impact on the system performance and energy consumption. In this study, no significant membrane fouling was observed, however, minute traces of fouling in the form of foreign functional groups could be observed in the attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) spectrums of the used membranes. Additionally, the observation of negligible changes in baseline 2 (membrane control) Re and Jw results suggested the possible occurrence of membrane fouling during the main experiment (dye-driven FO system).

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Falzarano, Aaron M. « An evaluation of energy consumption and emissions from intermodal freight operations on the Eastern Seaboard : a GIS network analysis approach / ». Online version of thesis, 2008. http://hdl.handle.net/1850/7530.

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Hoenderboom, Stan. « Evaluation of car engine heating systems in the Jämtland-Härjedalen region, northern Sweden ». Thesis, Mittuniversitetet, Avdelningen för ekoteknik och hållbart byggande, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-29089.

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Objective of this thesis is to identify potential energy savings regarding engine heating of cars within the Jämtland-Härjedalen county, northern Sweden. This could contribute to energy consumption reduction goals of Sweden. Potential energy savings are defined by comparing the current energy consumption with the energy consumption of different energy saving scenarios in terms of behavioural change and technological choices. Energy consumption, both current and potential is modeled in excel based on data derived from quantitative investigation and literature review. Engine heating is identified as an energy consumer, the energy saved by fuel consumption reduction (7,77 TJ/year) does not overcome the invested energy to heat engines (26,36 TJ/year). Engine heating reduces engine wear, fossil fuel consumption (0,34 TJ/year) and emissions currently. Regarding the choice of technology using more automatic time adjustment reduces energy consumption, engine wear, emissions and fossil fuel consumption. Other scenarios show a compromise between energy consumption reduction on one side and fossil fuel consumption reduction in combination with reduced engine wear and emissions on the other side.

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Gunaratne, Priyanga Chamara. « Design and evaluation of new power management methods to reduce direct and induced energy use of the internet ». [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001879.

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Lisso, Mussa. « Evaluating the effect of operating variables on energy consumption in stirred mills Mussa Lisso ». Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/5299.

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Includes abstract.
Includes bibliographical references.
High grade ores have largely been depleted and those currently being treated are low grade, complex and sometimes finely disseminated, requiring fine grinding to liberate valuable minerals. For fine grinding applications, conventional tumbling mills are energy intensive. More energy efficient technologies such as stirred mills have been developed and widely used for fine and ultra-fine grinding. In this study, the effects of residence time, solids concentration, impeller speed, impeller type, media size and media density on energy consumption in a batch vertical stirred mill were investigated. The effect of energy on mill performance was assessed using the perfect mixing mill model. In addition, the effect of media stress intensity on grind and energy efficiency at constant residence time was also investigated. It was found that irrespective of the method of altering the energy input, the fineness of grind improved with increase in the specific energy input. This suggests that energy is the key driver for size reduction. The perfect mixing model can be used to assess mill performance and the breakage rates generally increased with increase in the specific energy input, impeller speed and solids concentration. The media stress intensity approach is useful in assessing mill performance in stirred mills at constant residence time. The fineness of grind improved when the media stress intensity was varied from 4.41×10-3 to 27.41×10-3Nm. In addition, the specific energy required to produce material below 25μm and 38μm decreased with an increase in the media stress intensity. When slurry density effects were considered, an optimum stress intensity was observed with respect to specific energy required to produce material below 25μm and 38μm. It was recommended that additional test work be carried out to investigate the effect of media size in the range -6.7mm + 2mm on energy efficiency. It was also recommended that tests be carried out at impeller speed between 600rpm and 1500rpm to assess how mill performance increases even at relatively high impeller speeds. In addition, a model predicting the specific energy using the impeller speed and solids concentration can also be developed.

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Šicová, Pavlína. « Energetické hodnocení krasobruslařské haly ». Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227857.

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The diploma thesis contains an energy audit of the figure skating hall. In the first part I focused on the analysis of the topic, fire regulations and laws relating to given theme, recent technical, theoretical and experimental solutions in practice. In the next part, I compiled the of building energy audit of building, including its mandatory annexes. In the last part, I presented the results of measurements in the evaluated object.

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Mota, Rafael Perazzo Barbosa. « Mecanismos para a melhoria do desempenho de sistemas RFID passivos ». Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/45/45134/tde-08122015-093352/.

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A Identificação por radiofrequência (Radio Frequency Identification - RFID) tem revolucionado a forma de identificar objetos, sendo usada desde aplicações de controle de estoques até o processo automatizado de pagamentos. Sua ampla aceitação e aplicabilidade tem estimulado pesquisadores a criar cada vez mais aplicações. Um problema chave da RFID são as colisões que ocorrem na identificação por meio dos protocolos de acesso múltiplo. Como, na prática, um leitor precisa identificar várias etiquetas em sua área de cobertura, algumas etiquetas podem responder ao mesmo tempo o que gera colisões e desperdício de recursos. Por este motivo, torna-se de grande valor um estudo abrangente sobre como melhorar a identificação das etiquetas de modo a reduzir o número de colisões. Além disso, aspectos como consumo de energia e tempo necessário para identificação também devem ser levados em consideração, uma vez que a utilização cada vez maior de dispositivos alimentados à bateria tem sido observada na prática. Esta tese investiga a categoria de protocolos anticolisão denominada Frame Slotted Aloha - FSA, pois é a categoria que possui maior potencial de utilização prática em sistemas RFID. Além disso, as diferentes métricas de análise de desempenho são também analisadas e categorizadas, uma vez que identificou-se que um conjunto de métricas devem ser observadas com o intuito de realizarem-se comparações justas com as propostas da literatura. Descobriu-se que a maioria das propostas não levam em consideração os aspectos chave de tempo e energia, assim como a característica de ser fácil de implementar e baixa complexidade. Esta tese propõe quatro algoritmos que visam diminuir o consumo de energia e o tempo do processo de identificação das etiquetas mantendo-se as características de baixa complexidade e similaridade com o padrão atual EpcGlobal Classe 1 Geração 2 (C1G2). O primeiro mecanismo visa diminuir a quantidade de respostas desnecessárias em cenários de localização e rastreamento. Os demais consistem em três propostas de algoritmos anticolisão para sistemas RFID. Os dois primeiros diferem na forma como o tamanho inicial de quadro é definido e como as colisões são tratadas, representando evoluções progressivas em direção a um melhor desempenho. O terceiro considera a ocorrência do efeito captura, o que traz a necessidade de mudanças no funcionamento do algoritmo anterior. Resultados de simulação mostram que os quatro mecanismos podem melhorar propostas existentes sem aumento de complexidade, resultando consequentemente em diminuição de recursos desperdiçados. Além disso também foram desenvolvidos dois softwares de apoio aos mecanismos propostos: nsRFIDsim e jRFIDsim. O primeiro trata-se de um módulo para o simulador ns-2 que simula um sistema RFID passivo. O segundo implementa uma proposta de benchmark para avaliação de desempenho de algoritmos anticolisão para RFID, visando fornecer para a comunidade científica uma forma padronizada de avaliar este tipo de algoritmo.
The Radio Frequency Identification - RFID has revolutionized the way objects are identified, being used in several areas, from inventory control applications to automated payment process. Its wide acceptance and applicability has stimulated researchers to create more and more new applications. One RFID key problem is the collisions on identification by means of multiple access protocols. Since generally, a reader needs to identify multiple tags in its coverage area, some tags tend to reply at the same time which can cause collision and waste of resources. For this reason a comprehensive study on how to improve the identification of tags in order to reduce the number of collisions becomes important. Additionally, issues such as energy consumption and time required for identification must also be taken into consideration, since an increasing use of battery-powered devices has been observed in practice. This thesis investigates the category of anti-collision protocols called Frame Slotted Aloha - FSA, as it is the category that has the greatest potential for practical use in RFID systems. Further analysis of the different performance metrics are also analyzed and categorized, since it was identified that a set of metrics must be observed in order to carry out up fair comparisons with the proposals found on the literature. It was found that most of the proposals do not consider the key aspects of time and energy as well as the characteristic of being easy to implement and having low complexity. This thesis proposes four algorithms aimed at reducing the consumption of energy and the time to identify the tags while maintaining the characteristics of low complexity and similarity to the current standard EPCglobal Class 1 Generation 2 (C1G2). The first mechanism aims to decrease the unnecessary answers in locating and tracking scenarios. The other ones consist of three proposals for anti-collision algorithms for RFID systems. They differ in how the initial size is defined and how collisions are resolved, representing progressive evolutions toward a better performance. The third one considers the occurrence of the capture effect, which brings the need for changes in the previous algorithm operation. Simulation results show that the four mechanisms can improve existing proposals without increasing complexity, resulting in consequent energy savings. In addition we have also developed two softwares to evaluate the proposed mechanisms: nsRFIDsim and jRFIDsim. The former is a module for the ns-2 simulator that simulates a passive RFID system. The second one implements a proposal for benchmark performance evaluation of anti-collision algorithms for RFID in order to provide to the scientific community a standardized way to assess this type of algorithm.

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Van, Schoor Jan Cornelius Rudolph. « Evaluation of the batch press as a laboratory tool to simulate high and medium-pressure roller crushers ». Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/37315.

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High and medium-pressure roller crushers operate on the principle of inter-particle crushing by crushing material in a packed bed. Although reference in the study is made to high-pressure roller crushers, the work was done with medium–pressure roller crushers i.e. the Loesche mill and the Horomill. The difference in pressures between these equipment and high-pressure grinding rolls (HPGR) from measurements done by FCB, the supplier of the Horomill, was that the medium-pressure equipment operates at pressures of 30 MPa whilst the HPGR operates at pressures as high as 100 MPa. In this study, the differences between single particle and inter-particle crushing and the applicability of the batch press to predict the energy consumption and particle size distributions for medium-pressure roller crushers were investigated. Two phases of crushing were identified and investigated. The first phase occurs when the material is still being drawn into the gap between the rollers. The second phase, called packed bed crushing, occurs when the material is in the gap between the rollers. Crushing and milling energy requirements are discussed with specific reference to the energy models proposed by Bond and Rittinger along with the shortcomings of both these models. These models postulate that the comminution energy is an inverse function of product size. This is proven to be true in this study, but where certain constants are suggested in the aforementioned correlations, this study revealed that these constants are not fixed for all applications but varies for different types of ore. The results were determined for 80% as well as 50% mass passing size. Kick proposed that the energy requirements are a function of the reduction ratio. A model used for roller crushers that is similar to what Kick proposed was also investigated. This was also found to be valid but again, the coefficients in the model vary for the different materials. A new method for predicting the work index of an ore for inter-particle crushing was investigated, which involves using a piston press in which a bed of material is pressed to a predetermined pressure. The proposed method was evaluated using pilot test data obtained with a Horomill, as well as with a pilot Loesche mill. The results indicate that the correlation between the batch press and the pilot mills are poor. The Rosin-Rammler description for particle size distribution was applied and compared with other descriptions. The particle size descriptions of products from the batch press and pilot mills were compared and although there are differences, the batch press can be used to prepare material for initial research in a project. From this study it is clear that, especially when tests are done on an unknown ore body, a work index such as Bond’s, cannot be used for plant design and economic studies unless some pilot plant tests are done to confirm the relationship between energy consumed and product size.
Dissertation (MEng)--University of Pretoria, 2012.
gm2014
Materials Science and Metallurgical Engineering
unrestricted

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Bohlmann, Jessika Andreina. « Evaluating the impacts of energy and environmental policy on South African households ». Thesis, University of Pretoria, 2020. http://hdl.handle.net/2263/76004.

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This thesis investigates how different policies and measures designed to reduce CO2 emissions – i.e. carbon tax and energy efficiency policies – in South Africa will affect South African households. The contribution of this study lies with evaluating South African households at a disaggregated income level from low to high-income appreciating the fact that households at different levels are impacted differently by the implementation of policies at national level. In order to evaluate such impacts, the study started with profiling the households’ electricity consumption patterns in South Africa through the years and comparing them with the rest of the world. The next objective was to comprehend – implementing an Auto Regressive Distributed Lag (ARDL) econometric model – the determinants of electricity consumption of the residential sector in the country. Finally, by using a Computable General Equilibrium (CGE), the study examined various policy scenarios designed to reduce emissions and its effects on different households, particularly the low-income ones that do not have the capital to absorb the impacts. The results showed that low-income households are affected differently than the rest of South African households by the national policies implemented to reduce CO2 emissions and combat climate change. However, given the way the carbon tax and energy efficiency policies are designed, low-income households should be affected minimally.
Thesis (PhD)--University of Pretoria, 2020.
National Research Foundation (NRF)
Economics
PhD (Economics)
Unrestricted

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Octaviani, Julio Cesar. « Avaliação de secadores horizontais rotativos com utilização de lenha e gas liquefeito de petroleo em secagem de cafe cereja descascado desmucilado ». [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257230.

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Orientador: João Domingos Biagi
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
Made available in DSpace on 2018-08-04T08:37:02Z (GMT). No. of bitstreams: 1 Octaviani_JulioCesar_D.pdf: 4895521 bytes, checksum: 7f263de570a6e904ee68d3965a3297cc (MD5) Previous issue date: 2005
Doutorado
Tecnologia Pós-Colheita
Doutor em Engenharia Agrícola

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Ismail, Lokman Hakim. « An evaluation of bioclimatic high rise office buildings in a tropical climate : energy consumption and users' satisfaction in selected office buildings in Malaysia ». Thesis, University of Liverpool, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491107.

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This research has been carried out with the aim to investigate how high rise office building design in tropical climate can contribute in reducing energy consumption while maintaining comfort. The main objective of this study is to compare the performance of a sample of bioclimatic high rise office blocks with that of conventional ones when situated in a tropical climate such as that in Malaysia. The research firstly reviewed all the characteristics of bioclimatic buildings in the Malaysian Peninsula particularly the traditional Malay house and the transformation through time. Secondly, the research studied some design planning and architecture of several high-rise office buildings principally the bioclimatic approaches. Thirdly, the claimed benefits of bioclimatic design approach for high rise office buildings were examined in the results of previously conducted research projects, dealing with energy consumption and design approaches which compares the bioclimatic and conventional high rise. The performance was measured according to a combination of technical and social criteria: direct observation on various architectural aspects, environmental measurement and users' perception of comfort and satisfaction with their working environment via questionnaires. The energy consumptions were compared based on the electricity bills recorded for at least a year period. The local building energy index is used as the benchmark to check whether there were real energy savings in the bioclimatic high rise office blocks or otherwise. The major finding of this work is that the occupants in bioclimatic high rise office buildings have a higher level of satisfaction with their working environment than those in conventional office blocks. There is evidence that bioclimatic high rise office buildings are energy efficient as the most recent bioclimatic high rise office building (Menara UMNO), has a lower energy index than the ASEAN standard and within the latest Malaysian Standard related to energy efficiency. In the past, high rise buildings have been perceived as inefficient users of energy, with the new bioclimatic design concept and technologies, there is no doubt that high rise office buildings in the future would be much better in design that provide better environment to the users and consume less energy.

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Sultan, Sahira. « Cost Evaluation of Building Space Heating ; District Heating and Heat Pumps ». Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-37137.

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Climate change and energy efficiency has become a matter of concern in recent times; therefore, energy efficiency of buildings has drawn major attention. According to the European Commission, EU countries must improve energy efficiency of existing buildings by retrofitting and renovating the buildings. A case study of a renovated commercial building is considered in this degree project. A model of the building is developed in the IDA Indoor Climate and Energy (IDA ICE) software. The model is then augmented to include renovations in the building. Further, the model is simulated in IDA ICE before and after renovations to investigate the impact of renovations on energy consumption of the building for one year. The simulation results indicate peak demands of district heating that occur in the coldest days of the year. The peak demands of energy are expected to increase the district heating cost because they serve as a basis for new pricing model introduced by the energy providers. Hence, it is important from the customer point of view to reduce the peak loads for cost shavings. The project work also provides an insight into the alternative source of energy such as heat pumps to reduce the peak load demands of district heating.

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Mostowfi, Mehrgan. « Improving the Energy Efficiency of IEEE 802.3az EEE and Periodically Paused Switched Ethernet ». Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3623.

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It is estimated that networked devices consumed about 150 TWh of electricity in 2006 in the U.S. which has cost around $15 billion and contributed about 225 billion lbs of CO 2 to greenhouse gas emissions. About 13.5% of this energy is consumed by network equipment such as switches and routers. This thesis addresses the energy consumption of Ethernet, and designs and evaluates improvements on existing methods to reduce the energy consumption of Ethernet links and switches. Energy Efficient Ethernet (EEE) is an emerging IEEE 802.3 standard which allows Ethernet links to sleep when idle. In this thesis, a performance evaluation of EEE is completed. This evaluation replicates previous work by Reviriego et al. in an independent manner. The performance evaluation shows that EEE overhead results in less energy savings than expected. A new method based on Packet Coalescing is developed and evaluated to improve the energy efficiency of EEE. Packet Coalescing bursts packets such that EEE overhead is minimized. The results show that EEE with Packet Coalescing for 10 Gb/s Ethernet can achieve very close to ideal (or energy proportional) performance at the expense of an insignificant added per packet delay. Periodically Paused Switched Ethernet (PPSE) was previously proposed and prototyped by Blanquicet and Christensen in 2008. PPSE uses periodically sent notification packets to halt packet transmission into a LAN Switch and thus allowing the switch to sleep periodically. In this thesis, a first performance evaluation of PPSE is completed. The evaluation in this thesis shows that a PPSE for 10 Gb/s Ethernet LAN Switches achieves either significant energy savings at the expense of an excessive packet delay, or less than expected savings with a less than human response time added per-packet delay. An improvement to PPSE (Adaptive PPSE) is proposed and developed based on an adaptive policy. The adaptive policy considers past traffic load to determine whether to put the switch to sleep or not. The evaluation shows that Adaptive PPSE can achieve very close to ideal performance at the expense of an added average per packet delay which is less than half of the human response time.

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Fahrenholz, Adam Charles. « Evaluating factors affecting pellet durability and energy consumption in a pilot feed mill and comparing methods for evaluating pellet durability ». Diss., Kansas State University, 2012. http://hdl.handle.net/2097/13633.

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Doctor of Philosophy
Department of Grain Science and Industry
Keith C. Behnke
A series of experiments was conducted to compare methods used to evaluate the durability of animal feed pellets, as well as to investigate the potential for modeling the effects of formulation and processing factors on both pellet durability index (PDI) and pelleting energy consumption, measured in kilowatt hours per ton (kWh/ton). Seven different factors, including ground corn particle size, added fat level, inclusion of distillers dried grains with solubles (DDGS), feed rate, steam conditioning temperature, conditioner retention time, and pellet die thickness (L:D ratio) were examined. Each factor was evaluated at two levels, and treatments were developed in order that all factor to factor comparisons could be made. Pellet samples were analyzed according to the standard method as described in ASAE S269.4, a modification of this method, and by using the NHP100 pellet tester set to each of its four testing intervals (30, 60, 90, and 120 seconds). The standard method was found to provide the most consistent and repeatable determinations of pellet durability, and was found to correlate well with the modified method, as well as with the NHP100 results at 30 and 60 seconds. Physical attributes of feed pellets, such as pellet hardness, bulk density, and moisture content were found to have significant, but weak correlations with pellet quality. Pellet quality was found to be significantly influenced by all factors other than ground corn particle size and feed rate. Higher fat level, lower conditioning temperature, and the thinner pellet die most significantly lowered pellet quality, with increasing effect respectively. A regression model was developed that was able to predict pellet durability within an average of 1.1 PDI. Pelleting energy consumption was found to be significantly influenced by all seven factors, with the higher fat level, thinner pellet die, and higher conditioning temperature most improving efficiency, with increasing effect respectively. A regression model was developed that was able to predict energy consumption within an average of 0.3 kWh/ton. The successful creation of regression equations demonstrates that there is potential for modeling and optimizing pellet quality and energy consumption within a pelleting operation.

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Hansson, Jörgen. « Analysis and control of a hybrid vehicle powered by free-piston energy converter ». Licentiate thesis, KTH, School of Electrical Engineering (EES), 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4189.

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The introduction of hybrid powertrains has made it possible to utilise unconventional engines as primary power units in vehicles. The free-piston energy converter (FPEC) is such an engine. It is a combination of a free-piston combustion engine and a linear electrical machine. The main features of this configuration are high efficiency and a rapid transient response.

In this thesis the free-piston energy converter as part of a hybrid powertrain is studied. One issue of the FPEC is the generation of pulsating power due to the reciprocating motion of the translator. These pulsations affect the components in the powertrain. However, it is shown that these pulsations can be handled by a normal sized DC-link capacitor bank. In addition, two approaches to reduce these pulsations are suggested: the first approach is using generator force control and the second approach is based on phase-shifted operation of two FPEC units. The latter approach results in higher frequency and lower amplitude of the pulsations, which reduce the capacitor losses.

The FPEC start-up requirements are analysed and by choosing the correct amplitude of the generator force during start-up the energy consumption can be minimised.

The performance gain of utilising the FPEC in a medium sized series hybrid electric vehicle (SHEV) is also studied. An FPEC model suitable for vehicle simulation is developed and a series hybrid powertrain, with the same performance as the Toyota Prius, is dimensioned and modelled.

Optimisation is utilised to find a lower limit on the SHEV's fuel consumption for a given drivecycle. In addition, three power management control strategies for the FPEC system are investigated: two load-following strategies using one and two FPEC units respectively and one strategy based on the ideas of an equivalent consumption minimisation (ECM) proposed earlier in the literature.

The results show a significant decrease in fuel consumption, compared to a diesel-generator powered SHEV, just by replacing the diesel-generator with an FPEC. This result is improved even more by using two FPEC units to generate the propulsion power, as this increases the efficiency at low loads. The ECM control strategy does not reduce the fuel consumption compared to the load-following strategies but gives a better utilisation of the available power sources.

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Fonseca, Ramon Naiff da. « Optimization of the sizing and the energy management for a hybrid fuel cell vehicle including fuel cell dynamics and durability constraints ». Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0110/document.

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L'hydrogène à travers de l'utilisation des piles à combustible (PAC), est de plus en plus considéré comme une option énergétique possible au secteur des transports grâce à ces caractéristiques fonctionnelles. Cependant, la technologie liée à la mise en œuvre de véhicules alimentés par une pile à combustible n'a pas encore atteint le niveau de maturité requis. Ainsi, ce travail propose de traiter certaines de ces limitations qui existent encore. Plus précisément, trois thèmes représentent les objectifs de ce travail : Le dimensionnement optimal des éléments présents dans un véhicule hybride à pile à combustible. La gestion d'énergie optimale pour les applications en temps réel et intégrant les contraintes dynamiques du système PAC. Inclusion de la durabilité de la pile à combustible dans la gestion d'énergie du véhicule. Le premier thème est abordé à travers l'élaboration d'une méthodologie de dimensionnement adapté à un véhicule hybride à la pile à combustible. Dans une approche systématique, le dimensionnement proposé combine les exigences de performance présente dans les spécifications techniques du véhicule, les algorithmes d'optimisation, l'analyse de la mobilité de la population et la viabilité économique de la conception. Le deuxième objectif établi a été développé à l'aide d'une approche d'optimisation de la répartition de puissance entre la batterie et le système PAC. Par l'adoption d'une méthode d'optimisation globale combinée à une stratégie de commande prédictive et l'inclusion de la dynamique du système PAC, un algorithme de gestion d'énergie pour des applications de temps réel a été conçu. Enfin, la durabilité de la pile à combustible a été incluse dans ce travail par l'intégration de sa dynamique de dégradation dans le problème d'optimisation lié à la gestion d'énergie. Cette dynamique représente une contrainte à prendre en considération lors de la répartition de puissance entre le système PAC et la batterie
The hydrogen, through the use of fuel cell stacks (FC), has been increasily considered as an energy possible option for the transport sector. Nevertheless, the technology related to its implementation in fuel cell vehicles has not reached the required maturity level. Therefore, this work intends to deal some of these existing limitations. More precisely, three topics represent the objectives of this work: The optimal sizing of the element present in the fuel cell hybrid vehicle. The development of an optimal energy management strategy oriented for real time applications and including the dynamic constraints of the FC system. The inclusion of the fuel cell durability in the vehicle energy management strategy. The first topic is tackled by the development of a sizing methodology adapted to the fuel cell hybrid vehicle application. Using a systematic approach, the proposed sizing method combine the performance requirements present in the vehicle's technical specifications, optimization algorithms, population mobility behavior and the economic viability of the design. The second assigned objective was developed using an optimization approach for the power split between the battery and the FC system. Through the adoption of a global optimization method allied with a predictive control strategy and the inclusion of the FC system dynamics, it was created an energy management algorithm oriented for real time applications. Finally, the fuel cell durability was included in this work by the integration of its degradation dynamics in the optimization problem, which is related to the vehicle's energy management. Such dynamic represents a constraint that should be taken into account in the power sharing between the FC system and battery

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Mancuso, Martin. « Grid-connected micro-grid operational strategy evaluation : Investigation of how microgrid load configurations, battery energy storage system type and control can support system specification ». Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-40019.

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Operational performance of grid-connected microgrid with integrated solar photovoltaic (PV) electricity production and battery energy storage (BES) is investigated. These distributed energy resources (DERs) have the potential to reduce conventionally produced electrical power and contribute to reduction of greenhouse gas emissions. This investigation is based upon the DER’s techno-economic specifications and theoretical performance, consumer load data and electrical utility retail and distribution data. Available literature provides the basis for DER specification and performance. Actual consumer load profile data is available for residential and commercial consumer sector customers. The electrical utility data is obtained from Mälarenergi, AB. The aim is to investigate how to use simulations to specify a grid connected microgrid with DERs (PV production and a BES system) for two consumer sectors considering a range of objectives. An open-source, MATLAB-based simulation tool called Opti-CE has successfully been utilized. This package employs a genetic algorithm for multi-objective optimization. To support attainment of one of the objectives, peak shaving of the consumer load, a battery operational strategy algorithm has been developed for the simulation. With respect to balancing peak shaving and self-consumption one of the simulations supports specification of a commercial sector application with 117 kWp PV power rating paired with a lithium ion battery with 41.1 kWh capacity. The simulation of this system predicts the possibility to shave the customer load profile peaks for the month of April by 20%. The corresponding self-consumption ratio is 88%. Differences in the relationship between the load profiles and the system performance have been qualitatively noted. Furthermore, simulation results for lead-acid, lithium-ion and vanadium-redox flow battery systems are compared to reveal that lithium ion delivers the best balance between total annualized cost and peak shaving performance for both residential and commercial applications.

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Fojtů, Pavel. « Energetické hodnocení obytných budov ». Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226012.

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This master thesis offers two cost-saving measures to reduce the energy consumption of a residential building. These measure include insulation of the building envelope, domestic hot water by solar colectors and heat recovery.

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Andrade, Diogo Elias da Vinha. « Modelo para predição de resultados de ensaios de sistemas de refrigeração em tempo real ». Universidade Tecnológica Federal do Paraná, 2012. http://repositorio.utfpr.edu.br/jspui/handle/1/207.

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Atualmente, a análise de desempenho de sistemas de refrigeração domésticos é realizada através de ensaios experimentais normalizados. Durante esses experimentos, diversas variáveis como pressões de trabalho, temperaturas em diversos pontos do sistema, corrente elétrica e potência consumida, são monitoradas. Porém, em muitos casos são necessárias mais de 24 horas para execução de um teste experimental (e.g., teste abaixamento de temperatura). Tendo em vista o tempo despendido nestes testes, propõe-se no presente trabalho um modelo matemático semi-empírico capaz de predizer o comportamento das variáveis do sistema testado e, com isso, antecipar o final do ensaio. O modelo, desenvolvido através das leis de conservação da massa e da energia, apresenta parâmetros que são ajustados a partir de informações experimentais obtidas durante a execução do próprio teste. Após a inicialização do ensaio, a cada período de tempo prédeterminado, os dados medidos são utilizados para determinar os parâmetros empíricos do modelo. Obtidas as constantes, simula-se o comportamento das principais variáveis do sistema de refrigeração até a condição de regime permanente. Com isso, o teste experimental pode ser finalizado com antecedência. O modelo desenvolvido é capaz de prever com boa precisão, a partir de duas horas de teste, a variação da vazão mássica e da pressão de sucção (com diferenças da ordem de 10% em regime permanente quando comparadas às variáveis experimentais), da pressão de condensação (com diferença da ordem de 5%) e da temperatura da parede do condensador (diferença da ordem de 2°C).
The performance of household refrigeration systems are usually evaluated through experimental tests carried at in temperature and humidity controlled chambers. During the tests, the discharge and suction pressures, the temperature in several system positions, and the compressor power are measured. These tests are expensive and time-demanding, e.g., a single pull-down test can take more than 24 hours to be performed. Although the mathematical models have been proposed for decades as an alternative to the experiments, they are not sufficiently reliable to substitute completely the tests. Therefore, the current work proposes a semiempirical mathematical model to predict the system performance with the purpose of reducing the test time instead of replacing it. The model is based on the mass and energy conservation equations in which the constant parameters, such as conductance and capacitances, are calibrated from previous measured values of temperature and pressure. As soon as the parameters are obtained, a simulation is performed to forecast future values of temperature, pressure and compressor power and therefore, to anticipate the end of the test. Calibrations and simulations can be continuously performed as the test evolves. Preliminary results show that steadystate values of discharge and suction pressures can be predicted within error bands of 5 and 10%, respectively, after only two hours of a pull-down test being performed.

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Barzda, Albertas. « Study and evaluation of actual nutrition and nutrition habits of Lithuanian adult population ». Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20111102_111244-87383.

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There is no doubts that proper and healthy nutrition helps to prevent a number of chronic non-communicable diseases and is one of the key determinants of good health and life quality. The aim of the study is to evaluate the actual nutrition and nutrition habits of Lithuanian adult population. A random sample of 3,000 Lithuanian residents aged from 19 to 65, representing Lithuanian adult population, was set for this study. Nutrition habits were investigated using nutrition questionnaire, food consumption was investigated using 24 hours recall methodology and special Atlas of Foodstuffs and Dishes portion sizes. Presented study is the first case, where the complexed data about the actual nutrition, nutrition habits and BMI of Lithuanian adult population was analyzed and comprehensively evaluated. According to socio-demographic determinants it was examined and evaluated consumption of separate foodstuffs as well as daily intake of nutrients (proteins, fats (including saturated and unsaturated fatty acids), carbohydrates (including sugars), dietary fibers, vitamins, minerals, etc.), and their consistency within the recommendations. There were established trends of changes in Lithuanian adult population nutrition and BMI, as well as links between respondents’ attitude towards some aspects of the nutrition (nutrition impact on health, consumption of fruits and vegetables, consumption of products containing more saturated fatty acids, heavy salt consumption, iodine salt consumption... [to full text]
Tinkama ir sveika mityba padeda išvengti daugelio lėtinių neinfekcinių ligų ir yra vienas iš svarbiausių veiksnių, lemiančių žmonių sveikatą ir gyvenimo kokybę. Todėl šio darbo tikslas buvo įvertinti suaugusių Lietuvos gyventojų faktišką mitybą bei mitybos įpročius. Buvo sudaryta atsitiktinė 3000 Lietuvos suaugusių (19–65 m. amžiaus) gyventojų imtis; mitybos įpročiai tirti, naudojant apklausos anketą; faktiškos mitybos tyrimai atlikti pagal standartinę 24 valandų apklausos metodiką, panaudojant specialiai šiam tikslui parengtą Maisto produktų ir patiekalų porcijų nuotraukų atlasą. Disertaciniame darbe pirmą kartą išanalizuoti ir kompleksiškai įvertinti duomenys apie suaugusių Lietuvos gyventojų faktišką mitybą, mitybos įpročius, gyventojų KMI; išnagrinėtas ir įvertintas pagal sociodemografines determinantes atskirų maisto produktų suvartojimas bei su jais gaunami maistinių medžiagų (baltymų, riebalų, tarp jų sočiųjų ir nesočiųjų RR; angliavandenių, tarp jų cukrų, skaidulinių medžiagų, taip pat vitaminų, mineralinių medžiagų ir kt.) kiekiai per parą bei jų atitikimas Rekomenduojamoms paros normoms. Taip pat buvo įvertintos Lietuvos suaugusių gyventojų mitybos ir kūno masės indekso pokyčių tendencijos bei nustatytos mitybos ir mitybos įpročių sąsajos su respondentų požiūriu į tam tikrus mitybos aspektus (mitybos įtaką sveikatai, daržovių ir vaisių vartojimą, produktų, turinčių daugiau sočiųjų riebalų rūgščių, vartojimą, gausų valgomosios druskos vartojimą, joduotos druskos... [toliau žr. visą tekstą]

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Simon, Lily. « Running on Empty : Investigating the Production and Consumption Paradox of Biofuel Policy in the United States ». Scholarship @ Claremont, 2015. http://scholarship.claremont.edu/pitzer_theses/63.

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In an attempt to achieve energy independence, rural economic development, and greenhouse gas emissions reduction, the United States has turned to fuels derived from agriculture. The U.S. Congress and Environmental Protection Agency mandated the blending of biofuels into conventional gasoline until 2022 under the Renewable Fuel Standard. However, largely missing from the discussion of biofuels is their feasibility regarding environmental protection and end-use marketing to consumers. This thesis investigates the motive for biofuel mandates in the U.S., the irony in the EPA’s decision to back a resource-exhaustive fuel source, and the questionable ability of the U.S. to supply and consume greater volumes of biofuels in the transportation sector. Barriers to consumption are outlined as increased production costs and high market fuel prices, strong political backing of traditional energy sources, and environmental implications of production on ecosystems in certain regions of the United States. By analyzing Iowa and Texas as two biofuel-producing states held in high regards for biofuel production capacity—yet varying degrees of consumption—the feasibility of reaching federal biofuel mandates and promoting this alternative fuel is determined.

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Michaelsson, Ludvig, et Sebastian Quiroga. « Design and evaluation of an adaptive dairy cow indoor positioning system : A study of the trade-off between position accuracy and energy consumption in mobile units with extreme battery life ». Thesis, KTH, Maskinkonstruktion (Inst.), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-190203.

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With growing farm sizes, increasing work load, and increasing social and legislative demands for loose housing, health monitoring of farm animals is playing a bigger role for farmers worldwide. A type of information that can be used to determine the health status of dairy cows is positional data. However, since dairy cows spend a lot of time indoors in protection from various weather conditions or to perform other activities, GPS solutions are not sufficient. Moreover, the devices that the dairy cows carry must have a long battery life in order to avoid frequent system maintenance. This thesis researches possible system solutions to enable indoor positioning of dairycows within loose housed freestall barns. The proposed system configuration is then optimized in terms of energy consumption, and the trade-off between dynamic energy consumption and position accuracy is investigated. Previous research has focused on one or the other, and the development of systems with extreme battery life has not been a priority. The proposed system uses a proprietary 433MHz radio frequency band to estimate the dairy cows’ positions, and accelerometer data to adaptively alter estimation frequency to minimize energy consumption. After the optimization process, the proposed system is shown to have a battery life of at least two years with an accuracy of approximately 7–8m and a precision of 11–12 mutilizing four anchor nodes in an experimental barn. The theorized correlation of the position accuracy and energy consumption could not be found. Keywords: indoor positioning, dairy cows, weighted non-linear least squares, energyconsumption, agriculture, system design, optimization, positioning accuracy, Sub GHzradio, battery life
Med växande gårdsstorlekar, ökande arbetsbelastning, påtryckningar från samhället och lagstiftning för lösdrift, gör att hälsoövervakning av gårdsdjur spelar en större roll för jordbrukare världen över. En typ av information som kan användas för att bestämma mjölkkors hälsa är positioneringsdata. Eftersom mjölkkor spenderar mycket tid inomhus för att skyddas mot väder, eller för att utföra andra aktiviteter, så lämpar sig inte lösningar baserade på GPS. Utöver det så krävs det att enheterna som korna bär med sig har en lång batteritid för att undvika frekventa systemunderhåll. Den här masteruppsatsen undersöker potentiella systemlösningar för att möjliggöra inomhuspositionering av mjölkkor i lösdriftsladugårdar. Den valda konfigurationen är sedan optimerad med avseende på energikonsumtion. Därefter undersöks förhållandet mellan dynamisk energikonsumtion och lokaliseringsnoggrannhet, tidigare forskning har fokuserat på antingen eller. Utvecklingen av system med lång livslängd har inte heller varit en prioritet. Det föreslagna systemet använder sig utav proprietära radiotekniker på 433MHz-bandet för att skatta mjölkkornas position. Dessutom används accelerometerdata till att adaptivt justera skattningsfrekvensen för att minimera energikonsumtion. Efter optimeringsprocessen har det föreslagna systemet en batteritid på minst två år, med en noggrannhet på ungefär 7–8m och en precision på 11–12m, när endast fyra ankarnoder användes i en experimentladugård. Den teoretiserade korrelationen mellan lokaliseringsnoggrannhet och energikonsumtion kunde ej påvisas. Nyckelord: inomhuspositionering, mjölkkor, viktad icke-linjär minstakvadratmetod,energikonsumtion, jordbruk, systemdesign, optimering, lokaliseringsnoggrannhet, SubGHz radio, batteritid

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Čajčíková, Jolana. « Energetický audit polyfunkčního objektu ». Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-239943.

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The theme of this diploma thesis are the issue of energy evaluation of buildings and the reduction of energy consumption in the Czech legal system in the theoretical part, an analysis of energy consumption of the judged building in an old and new state in the calculation part and an energy audit of the main building of SRC Lihovar in Třemošnice according to Decree no. 480/2012 Coll. The three-storey main building of sports and rehabilitation center is located on the southern edge of city Třemošnice and it used to be a distillery until it has been renovated in 2013. There is a restaurant with a bowling room, hotel with two conference lounges, wellness, fitness and a swimming pool. The heat source for this building are two gas boilers, three heat pumps and solar collector array. There is partly forced and partly natural ventilation installed in the building.

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Alborz, Nakisa. « A Post Occupancy Evaluation (POE) Framework for Certified Sustainable Higher Education (HE) Residence Halls ». Digital WPI, 2014. https://digitalcommons.wpi.edu/etd-dissertations/332.

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"Numerous higher education (HE) institutions in the United States (US) have created sustainability agendas, including construction of sustainable buildings. More than 200 US HE institutions, have at least one Leadership in Energy and Environmental Design (LEED) certified building on their campus (Princeton Review 2012). With the growing student population and need to house them, residence hall construction is rising nationwide. A profile of newly constructed building types shows residence halls hold the largest median area (Princeton Review 2012). In an effort to assess if sustainable residence halls are performing sustainably, a series of post occupancy evaluation (POE) indicators were selected. POE indicators were chosen through a review of widely adopted sustainability rating systems, scientific literature and student occupant feedback. The selected indicators address a range of parameters including: water and energy consumption, occupant thermal comfort, occupant consumption behavior and education, noise insulation (indoor and outdoor), and Facilities Management (FM) operational feedback. Furthermore, specific indicators such as building energy management systems (BEMS), building automation control systems (BACS) and artificial intelligence (AI) agents were examined. The proposed POE indicator framework data was collected from various key stakeholders including: designers, HE FM departments, residential life personnel, and student occupants. The dataset includes: actual temperature (T) and relative humidity (RH) measurements of a LEED-Gold residence hall, actual water (9 residence halls) and energy consumption (4 residence halls) data, and feedback from designers, HE FM departments and 593 student occupants (LEED and non-LEED residence halls). The proposed POE indicator framework triangulates quantitative and qualitative data, via investigative and diagnostic techniques; creating a comprehensive building performance picture, vis-à-vis technical and non-technical parameters."

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Bedin, Janaina. « Avaliação do consumo energético em aviários Dark House, com e sem isolamento térmico : um estudo de caso na região de Palotina, Paraná ». Universidade Estadual do Oeste do Parana, 2015. http://tede.unioeste.br:8080/tede/handle/tede/769.

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Made available in DSpace on 2017-07-10T15:14:26Z (GMT). No. of bitstreams: 1 DissertacaoJanainaBedin.pdf: 4782834 bytes, checksum: 4c0a870502d04664c635db95ceb09e72 (MD5) Previous issue date: 2015-03-06
The production of poultry cuts suffered major investments in technology and genetic development in recent decades, trying to adapt to the conditions and requirements of the national and world market. Studies on the production through the analysis of systems and means of accommodation, show the economic importance of the sector, which has established itself as one of the most competitive in the agribusiness sector. The present work was the study of two aviaries dark house, with and without thermal insulation in their construction, are located in the city of Palotina, Paraná, trying to evaluate the variations in temperature, gas consumption and animal performance of the two systems . In terms of methodology, both facilities were checked temperature variation, with reading by J-type thermocouple sensors and recording in datalogger; consumption of LPG, with installation of individual volumetric meters; and the animal performance and the elimination of mortality and birds, feed intake and water and weight gain. At the end of the study it can be concluded that the aviary Dark House with Thermal Insulation (DHIT) showed better animal performance indexes, lower mortality and elimination, and greater weight gain. But when evaluated performance in the face of temperature conditions, the aviary Dark House Conventional (DHC) showed better suited to the production values, as bibliographic references.
A produção de aves de cortes sofreu grandes investimentos em tecnologia e desenvolvimento genético nas últimas décadas, buscando se adequar às condições e exigências do mercado nacional e mundial. Estudos acerca da produção, através da análise dos sistemas e meios de alojamento, demonstram a importância econômica do segmento, que se consolida como um dos mais competitivos no setor agroindustrial. Assim, o presente trabalho consistiu no estudo de dois aviários dark house, com e sem isolamento térmico em suas características construtivas, localizados na cidade de Palotina, Paraná, procurando avaliar as variações de temperatura, o consumo de gás e o desempenho animal dos dois sistemas. Em termos de metodologia, em ambas instalações, foram verificados a variação de temperatura ,com a leitura por sensores Termopar tipo J e registro em datalogger; o consumo de gás GLP, com a instalação de medidores volumétricos individuais; e o desempenho animal quanto, a mortalidade e eliminação das aves, o consumo de ração e água, e o ganho de peso. Ao final da pesquisa pode-se concluir que o aviário Dark House com Isolamento Térmico (DHIT) apresentou melhores índices de desempenho animal com, menor mortalidade e eliminação, e maior ganho de peso. Porém quando avaliado o desempenho frente às condições de temperatura, o aviário Dark House Convencional (DHC) apresentou valores mais adequados à produção, conforme referencial bibliográfico.

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Ait, el mahjoub Youssef. « Performance evaluation of green IT networks ». Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASG011.

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L'économie d'énergie dans les réseaux de télécommunication est un objectif majeur pour réduire la consommation globale. La part du domaine IT est déjà très élevée et tend à augmenter. En effet, de nombreuses techniques pour réduire la consommation dans d'autres industries ou services se traduit par plus de traitements informatiques et de télécommunications (l'approche ”Green by IT”) et donc par une augmentation de la consommation dans les domaines IT. Il est donc important d'un point de vue économique d'arriver à réduire la consommation énergétique par bit transmis ou calculé (l'approche ”Green IT” qui est au centre de notre approche). Dans le domaine des réseaux, l'optimisation énergétique repose principalement sur une adaptation de l'architecture et des ressources employées en fonction des flux à transporter et de la qualité de service promise. On cherche donc à adapter les ressources à la demande, ce qui se traduit par un dimensionnement dynamique et adapté à la charge. Ceci est par nature différent d'un dimensionnement au pire cas que l'on utilise généralement. Sur le plan technologique, cela nécessite que les équipements de réseaux disposent de modes ”sleep”,”deep sleep” ou ”hibernate” (terminologie variant selon les fournisseurs)mais qui sont tous associés au même concept: mettre en sommeil l'équipement pour réduire sa consommation d'énergie. Pour que le compromis performance/énergie soit pertinent, il parait important d'utiliser des formules de consommation énergétiques obtenues à partir de l'utilisation des ressources du réseau. Les méthodes que nous proposons relèvent de la théorie des réseaux de files d'attente, l'analyse des chaines de Markov (analytiquement en proposant de nouvelles formes produitet numériquement en suggérant de nouveaux algorithmes de résolution) et la théorie de la comparaison stochastique. Au niveau applicatif nous avons traité différentes problématiques: les mécanismes de DVFS avec un changement de vitesse des processeurs, la migration de tâche entre serveurs physique dans un centre de données (équilibre de charge, consolidation), les réseaux optique avec un remplissage efficace des conteneurs optiques, la distribution d'énergie intermittente dans un réseau de capteurs (et réseau LORA) notamment en proposant un nouveau modèle des réseaux à paquet d'énergie (EPNs)
Energy saving in telecommunication networks is a major objective to reduce overall consumption. The IT sector already has a very high contribution to this increase. Indeed, many techniques to reduce consumption in other industries or services results in more IT and telecommunications (the "Green by IT" approach) and therefore in an increase of consumption in IT domains. It is therefore important from an economical point of view to reduce the energy consumption per transmitted or calculated bit (the "Green IT" concept). In the networks domain, energy optimization is mainly based on an adaptation of the architecture and the resources employed according to the traffic flows to be transported and the promised quality of service. We therefore seek to adapt resources to demand, which results in a dynamic dimensioning adapted to the load. This is by nature different from the worst-case dimensioning commonly used. In terms of technology, this requires network equipment to have "sleep", "deep sleep" or "hibernate" modes (terminology varies among suppliers), but all of these modes are associated with the same concept: putting the equipment to sleep to reduce its energy consumption. For the performance/energy trade-off to be relevant, it seems important to use energy consumption formulas obtained from the network resource utilization. The approaches we propose are based on the theory of queuing networks, Markov chain analysis (analytically by proposing new product forms and numerically by suggesting new resolution algorithms) and the theory of stochastic comparison.At the application level we have addressed various issues: DVFS mechanisms with a change of processors speed, task migration between physical servers in a data center (load balancing, consolidation), optical networks with efficient filling of optical containers, intermittent power distribution in a sensor network (and LoRa network) including a new model of Energy Packet Networks (EPNs)

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Ibn-Mohammed, Taofeeq. « Optimal ranking and sequencing of non-domestic building energy retrofit options for greenhouse gas emissions reduction ». Thesis, De Montfort University, 2014. http://hdl.handle.net/2086/10501.

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Whether it is based on current emissions data or future projections of further growth, the building sector currently represent the largest and singular most important contributor to greenhouse gas (GHG) emissions globally. This notion is also supported by the Intergovernmental Panel on Climate Change based on projection scenarios for 2030 that emissions from buildings will be responsible for about one-third of total global emissions. As such, improving the energy efficiency of buildings has become a top priority worldwide. A significant majority of buildings that exist now will still exist in 2030 and beyond; therefore the greatest energy savings and carbon footprint reductions can be made through retrofit of existing buildings. A wide range of retrofit options are readily available, but methods to identify optimal solutions for a particular abatement project still constitute a major technical challenge. Investments in building energy retrofit technologies usually involve decision-making processes targeted at reducing operational energy consumption and maintenance bills. For this reason, retrofit decisions by building stakeholders are typically driven by financial considerations. However, recent trends towards environmentally conscious and resource-efficient design and retrofit have focused on the environmental merits of these options, emphasising a lifecycle approach to emissions reduction. Retrofit options available for energy savings have different performance characteristics and building stakeholders are required to establish an optimal solution, where competing objectives such as financial costs, energy consumption and environmental performance are taken into account. These key performance parameters cannot be easily quantified and compared by building stakeholders since they lack the resources to perform an effective decision analysis. In part, this is due to the inadequacy of existing methods to assess and compare performance indicators. Current methods to quantify these parameters are considered in isolation when making decisions about energy conservation in buildings. To effectively manage the reduction of lifecycle environmental impacts, it is necessary to link financial cost with both operational and embodied emissions. This thesis presents a novel deterministic decision support system (DSS) for the evaluation of economically and environmentally optimal retrofit of non-domestic buildings. The DSS integrates the key variables of economic and net environmental benefits to produce optimal decisions. These variables are used within an optimisation scheme that consists of integrated modules for data input, sensitivity analysis and takes into account the use of a set of retrofit options that satisfies a range of criteria (environmental, demand, cost and resource constraints); hierarchical course of action; and the evaluations of ‘best’ case scenario based on marginal abatement cost methods and Pareto optimisation. The steps involved in the system development are presented and its usefulness is evaluated using case study applications. The results of the applications are analysed and presented, verifying the feasibility of the DSS, whilst encouraging further improvements and extensions. The usefulness of the DSS as a tool for policy formulation and developments that can trigger innovations in retrofit product development processes and sustainable business models are also discussed. The methodology developed provides stakeholders with an efficient and reliable decision process that is informed by both environmental and financial considerations. Overall, the development of the DSS which takes a whole-life CO2 emission accounting framework and an economic assessment view-point, successfully demonstrates how value is delivered across different parts of the techno-economic system, especially as it pertains to financial gains, embodied and operational emissions reduction potential.

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Thèses sur le sujet « Evaluation of energy consumption »

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