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4212 Uppsatser om Energy Systems - Sida 66 av 281
Kontinuerlig RFID-detektering för batteridrivna system
This report deals with RFID systems and how to detect nearby tags with the Mifare standard using only a microcontroller and an antenna circuit.The aim was to investigate whether there was any possibility to continuously search for a nearby tag for a system operated with batteries without compromising the lifespan of the battery. At this time the system would take too long time to wake up and look for a tag to give a satisfactory battery lifespan, which should be done a couple of times every second.The report has two issues, namely:Is it possible to direct the microprocessor to detect and identify a nearby tag after the Mifare standard?What hardware is required for this to be possible?As the research method to provide answers to the above questions an action research was used. This approach has meant that the group worked on information retrieval, examined existing solutions, tested their own solutions and documented the results.The group examined an existing solution that can search for nearby tags with minimal energy consumption. An antenna circuit was built that was connected to the processor.
Byggnadens andra skepnad : En anpassning för att möta samhällets behov och krav
Population growth leads to an increased need for new buildings, both residential and commercial. The regulations of structural design also changes with time. From a sustainable community perspective it may be profitable if existing buildings, that no longer performs their original function, are reconditioned. Knowledge and understanding of the surroundings of the residence must be available. Regulations regarding accessibility to all has increased.
Arbetsmätningssystem på Scania Vehicle Service Information : En analys av nuläget samt framtagande av rekommendation för framtida utveckling
Scania CV is one of the world's largest truck manufacturer. It is not only the directproduction of vehicles and methods that are important for Scania but also the servicemarket handling spare parts, repairs and workshops. The department Vehicle ServiceInformation construct standard times through work measurement for particularworks in the workshops. The software application STAM is used in the servicemarket to create and store standard times which then are exported to theworkshops' own systems.The purpose of this master thesis is to analyse and evaluate the internal workmeasurement system that includes standard times and the software STAM. Also,based on external analysis and benchmarking of other systems suggest appropriatefuture development within the area for Scania Vehicle Service Information.In order to perform the investigation, interviews and studies have been doneinternally at the departments that are involved in work measurement as well asexternally at Scania workshops.
Stommaterial för villor - trä eller betong?
We have the tradition in Sweden to build villas and houses with a wooden framework. It has become natural for us because we have so much forest in our country. Building with wood has advantages, it is easy to process, but also disadvantages, as it is sensitive to moisture.Finland has long made use of the thermal blocks to build villas. It is a type of bricks that are a bit like a sandwich element, with a core of EPS and concrete on both sides of the core material. The concrete is hollow, so that after the walls has been bricked up you pour concrete into the hollow bricks.The issue of this report is to find out if concrete can be an alternative to wood as framework material in villas.
Elektronisk motorstyrning för ottomotorer
The combustion engines in today?s vehicles are getting more and more advanced and there are increasing demands on that the engines should operate during optimal conditions. Examples of internal combustion engine parameters which may be carefully controlled are the rate between fuel and air, that this gas mixture is homogenous enough and that it is ignited at the correct moment. Moreover, the requirements of these parameters vary depending on, among other, engine speed and load. To meet these requirements in all occurring operation conditions, it is required that many subsystems work together.
Industriella kundrelationer i teori och praktisk tillämpning
The purpose of this master?s thesis is to contribute to the development of business relationships between a supplier and its customers. The research area and research problem was further developed into three research questions. The research questions concerns the following subjects: the substance of business relationships and dimensions within relationships management that can be used in order to contribute to the development of a company?s business relationships.
Soil carbon, pH and yield development in a long-term humus balance trial
Agriculture has to be performed in a sustainable way in order to sustain high yields and to support a globally growing population. Functional soil properties are fundamental for high yields and in order to achieve good soil conditions sustainable management is a key. Loss
of soil organic material and increased soil acidity are problems associated with degradation of soils and hence less sustainable agriculture. In this thesis, the effect of different agricultural systems on soil organic matter, pH and yield was examined. The systems examined are a cereal system with straw removal or returning and a ley system, all with different nitrogen levels.
Prestandabaserad design genomkonceptuell energianalys : Performance-based design through conceptual energy analysis
This degree project aims to investigate the potential and possibilities for conceptual energyanalyses in the early stages of the design process. Many key decisions are made in theearly stages of a project regarding the shape and orientation of the building. Conceptualenergy analyses can provide the architects with insight regarding different design option?srelative energy performance.As the demands for more sustainable buildings increases, so does the need for earlyenergy analyses. Performing analyses in the early stage requires many assumptions andguesswork which could lead to a large margin of error.The offering from Autodesk is a module in Revit Architecture/MEP and the stand aloneprogram Project Vasari (under development).
Remburser och andra säkerhetsarrangmang vid internationell handel
AbstractWe live in a world today that is characterized by the Internet. We can get hold of people on the other side of the globe whenever we want and we can purchase what ever we want, from who ever we want, anytime we want. This development has made it important to find systems of dealing with the payment in a safe and secure way, both for a private person as well as for a company, when you do transactions with people far away, and those systems is the core of this essay. As a private person you sometimes need to transfer money to family members who live abroad and you can then use clean payments. This means that banks all over the world has systems which makes it easier when their customs wishes to transfer money abroad.
Självförsörjande elgenerering : Kan Orust bli självförsörjande på förnybar el?
Orust Kretsloppsakademi is a nonprofit organisation, with a goal of annually generate the same amount of electrical energy that is consumed. Orust is an island on the west coast of Sweden, north of Gothenburg. The population of 15 000 reaches 40 000 during summer, due to the large amount of vacationer. The total electricity demand is 174 GWh a year with a maximum power need of 32 MW. This report presents an analysis for the plausibility of their plan and from a power system stability perspective, the effects on the electrical grid.The conclusion is that the restraints for development of power generation from wind, solar and wave generation, are the power systems capability to transfer power, primarily in the transformers of the grid.
Kan grönt bli till guld? : En studie av miljöcertifieringars värde och utveckling i den svenska bygg- och fastighetssektorn
Certification systems, that assess companies? work with social and environmental issues, have emerged in an increasing number of industries. Today, there are environmental certifications for the food industry, the forestry, the fisheries sector and several more. In apparel industry, certification for sustainable working conditions has been of major impact. The property sector is no exception from other industries.
Till en älskad vän : materia och objekt som medier för överföring
With self-hypnosis as a method, I work with levels of consciousness in relation to practice. Focus lies in the relation between a language of materials and an inner experience. How do material expressions function as mediums of a spiritual matter between a beholder and me? The trance functions as a space for a spiritual contact/communication. Abstract images of crystalline glaze on ceramic tiles are direct results of these acts.
Expansionsmaskiner istället för strypventiler - en effektivisering
In Uppsala CHP Plant, there are six pressure reducing valves to reduce the pressure from 15 to 3 bars, before six absorption heat pumps. During the process the energy is conserved but losses occur in form of exergy. The aim of this thesis is to reduce the losses of exergy. This can be done by letting turbines replace the pressure reducing valves.In this thesis an investigation has been done of the conditions today, the conditions after the change from pressure reducing valves to turbines and a comparison of three different types of turbine solutions. The three examined solutions are one turbine, several helical screw expanders and several small turbines in parallel with asynchronous generators.The six absorption heat pumps have been divided into two groups; one group of four and one group of two absorption heat pumps.
Svalövs flyktingenhets arbete för nyanlända invandrare - en utvärdering med brukar- och intressentfokus
The following report is a constructive responsive evaluation of Svalövs communes unit for newly arrived refugees based on a qualitative user- and stakeholder model. The main purpose is to evaluate the units? quality from a user and stakeholder perspective. The main findings are that the users and stakeholders are satisfied with the quality of the units? services but request further social and structural participation.
Latent värmelagring i vattenburet uppvärmningssystem med elpanna för byggnadsapplikationer
Latent heat storage is a way to store thermal energy when a phase change material undergoes a phase change. The advantage of latent heat storage is the capability to store more energy per mass unit than other heat storage methods. The most commonly used phase change in latent heat storage is the transition between solid and liquid. Phase change materials can be divided into organics, inorganics and eutectics.In the Nordic electricity market the price of electricity is set every hour by Nordpool spot, which leads to price fluctuations because of changes in demand. The main goal of this report is to create a latent heat storage system in a single-family home and investigate the possibility to save money by charging the latent heat storage system when the price of electricity is low, and discharge when the price is high.The thermodynamic model consisted of a ?tube-in-tube? heat exchanger with phase change material in the outer tube and water as the heat transfer fluid in the inner tube.