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  • 401.
    Daunfeldt, Björn
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utveckling av Moodle2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Institutionen Tillämpad fysik och elektronik på Umeå Universitet använder sig av lärandeplattformen Moodle för hantering av kurser med tillhörande uppgifter och material kring dem. På Moodle laddar studenterna upp dokument och lärare betygssätter dem, vartefter en avklarad kurs registreras hos LADOK. Detta projekt kommer omfatta teori om hur Moodle är uppbyggt (version 2.4), hur utveckling av moduler sker, samt för- och nackdelar beroende på om operativsystemet Windows eller Linux används.Utvecklingen av moduler omfattar kodning av två stycken. Den ena modulen skall gå att implementeras till Moodle för att användas till kurser av institutionen för att underlätta kontrollen av inlämnade dokument som ännu ej är behandlade av lärare. Den andra är en generell modul som skapas i handledningssyfte för att senare kunna utvecklas vidare på, och implementeras till systemet om behov finns. Själva utvecklingen har skett i operativsystemet Ubuntu med programvaran Eclipse, Nano samt MySQL. Tillvägagångssätt för att beskriva Moodles systemet, samt för- och nackdelar kring operativsystemet skedde genom utbildning under projektets gång i form av läsning av manualer, forum och intervjuer med tekniker som jobbar med Moodle på Umeå Universitet.Projektet resulterade i att två fungerande moduler kodades med möjlighet att installeras på Moodle med version 2.4, även undersökningen av för- och nackdelar kring Windows och Linux är gjord vilket gav nog med information för att kunna göra en avvägning vad som är lämpligast att använda. En del grundläggande tester (dock ej mot Universitetets Moodle) visar att modulen för listning av dokument kan presentera inlämnade för vald kurs, och att enbart användare med behörighet kan komma åt modulen. En handledning för att skapa moduler är även inkluderad i denna rapport.

  • 402. De Alcantara Dias, Bruno Martin
    et al.
    Maria Lagana, Armando Antonio
    Justo, Joao Francisco
    Yoshioka, Leopoldo Rideki
    Dias Santos, Max Mauro
    Gu, Zonghua
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Model-based development of an engine control module for a spark ignition engine2018In: IEEE Access, E-ISSN 2169-3536, Vol. 6, p. 53638-53649Article in journal (Refereed)
    Abstract [en]

    A Spark ignition (SI) engine is a complex, multi-domain component of the vehicle powertrain system. The engine control module (ECM) for an SI engine must achieve both high performance and good fuel efficiency. In this paper, we present a model-based development methodology for an open architecture ECM, addressing the entire development lifecycle including a control algorithm design, parameter calibration, hardware/software implementation, and verification/validation of the final system, both with bench tests on a dynamometer and in a real vehicle on the road. The ECM is able to achieve similar performance as the original proprietary ECM provided by the original equipment manufacturer. Its flexible and modular design enables easy extensibility with new control algorithms, and development of new engine types.

  • 403.
    de Geyter, Sigrid
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Öhman, Marcus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Eriksson, Morgan
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Effects of non-quartz minerals in natural bed sand on agglomeration characteristics during fluidized bed combustion of biomass fuels2007In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 21, no 5, p. 2663-2668Article in journal (Refereed)
    Abstract [en]

    Most of the previous literature on fluidized bed agglomeration during biomass combustion is based on quartz as a bed material. Full-scale installations however often use natural sand, which apart from quartz may contain a high fraction of non-quartz minerals such as potassium feldspar and plagioclase. The objective of the present study was therefore to elucidate the effects of non-quartz minerals occurring in natural sand on the agglomeration behavior during fluidized bed combustion of biomass fuels. Three fuels typical for previously determined agglomeration mechanisms were chosen as model fuels: calcium-rich bark, potassium-rich olive residues, and silica- and potassium-rich wheat straw. Two different feldspar minerals were used: a potassium feldspar and a plagioclase, labradorite, which both occur in many commercial bed materials. Furthermore, olivine was used as a bed material as this mineral represents another type of bed material used in some fullscale installations. Quartz was used as a reference bed material. The effects of non-quartz minerals in natural sand on initial defluidization temperature were assessed during carefully controlled, bench-scale fluidized bed agglomeration experiments. Bed material samples and agglomerates were analyzed using scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS) in order to explore the occurrence and chemical composition of coating and attack layers on the bed particles and necks between agglomerated particles. Significant differences in agglomeration characteristics were found for the different minerals when bark and olive residue were combusted. Potassium-feldspar was shown to lower the initial defluidization temperature for combustion of bark and olive residues. Plagioclase and olivine on the other hand were found to increase the initial defluidization temperature as compared to quartz for the combustion of olive residue, but for bark combustion, they did not differ significantly from quartz. During combustion of wheat straw, all bed materials agglomerated shortly after the startup of the experiment. For bark and olive residue samples, attack layers were found on all bed materials and the composition of the inner attack layer and agglomerate necks differed significantly with the fuel/bed material combination. For wheat straw however, no continuous attack layers were found, and the bed material composition was concluded not to influence the agglomeration characteristics for this biomass. The results were used to suggest possible mechanisms involved in layer formation for the different minerals.

  • 404.
    de la Motte, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Kvalitetsjämförelse mellan videokodecs x264 och x2652014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The main goal of this study is to encode a video with the best quality that is also encoded in real-time. The streaming and live show industry is constantly developing to be able to fulfill the need for better codecs to produce videos of higher quality, more heavily compressed video files and faster encoding speed. This study uses two different methods to decide the quality of a video, the first method is a program that calculates every frame of an encoded video and then compares it to the frames of the raw, original video. The second method is a visual test that lets a person decide which of the codecs produces the better frames. This was made without the person knowing which frame was encoded with what codec. The study shows that x264 is superior to x265 when it comes to better quality with real time encoding. However x265 produces smaller sized files with the same or better video quality than x264. In earlier studies it shows that x265 is in fact superior in form of quality.

  • 405.
    Degerman, Patrik
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Lastfall vid vindkraftverk2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Wind power is being expanded rapidly in Sweden so also in northern parts, where Skellefteå Kraft is one of the companies building a lot. One of the areas being built by Skellefteå Kraft is in Blaiken, an area just outside of Arjeplog. In cold climates as it is in Blaiken big parts of the year there is a risk that the forming of ice on the wind turbines and the rotor blades. When the wind turbines are running there is a risk that ice will break loose and throw the ice with great force. This report, treats problem with ice and snow that tumbles and risks to injure personnel who are next to the wind turbines for work. The theory section of the report deals with how the icing occurs on the wind turbines and what type of ice that is formed and how the ice and snow that tumbles from the wind turbine is converted into a static load on a building. I have done surveys of what kinds of ice that fall down and how often it is done to be able to get an idea of what kind of loads that determines the dimension of the final roof to protect personnel. The investigation led to a vertical static point load at 25 kN which is placed in the most unfavourable point of the construction. With 25 kN as the main load the construction was dimensioned with a steel frame with HEA 140 and HEA 180 beams and columns.

  • 406.
    del Val Mäkinen, Isabell
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Entertainment with Head-Mounted Displays: Enhancing the Viewer Experience2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this thesis the main point was to see if you could enhance the spectator experience of a live event with a head-mounted display and eventually change the way we look at TV. This study was made with both a literature study, and interviews with users. During the interviews that were made, of sport and music events, it was shown that people were willing to use the technology in their homes but will not substitute the TV as long as the quality of the display in the device does not increase. Sports was the most common named event that people would watch with a head-mounted display, to get a more immersive experience than what you get at home today. It was clear what users wanted to control the cameras themselves while watching live events, so they could get the sense of feeling of being there.

  • 407. Deng, Na
    et al.
    He, Guansong
    Gao, Yuan
    Yang, Bin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Zhao, Jun
    He, Shunming
    Tian, Xue
    Comparative analysis of optimal operation strategies for district heating and cooling system based on design and actual load2017In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 205, p. 577-588Article in journal (Refereed)
    Abstract [en]

    Computational load significantly influences energy and cost savings when developing an operation strategy for a district heating and cooling system. In this study, a model was identified to study the effects of the difference between design load and actual load on an optimal operation strategy. The established model is strongly dependent on the economy principle, and the proposed optimal strategy could achieve a dynamic balance between the users' load and the system energy supply. This model was validated at 30% load rate, which demonstrated an obvious cost saving of 63.6% under the actual load and 42.2% under the design load. Based on the current strategy, the optimal strategy at different load rates was analyzed with respect to two characteristics of each subsystem: energy outputs and operation costs. Furthermore, in the optimal strategy, changes in total operation costs and cost savings rates under different load rates are also discussed. The results showed that, when the load rate was changed from 30 to 75%, the savings rates based on the design load were 42.2, 17.9, 2.5, and 12.6%, and the savings rates based on the actual load were 63.6, 49.8, 34.3, and 25.7%, respectively. Based on the actual load, the energy savings advantage of the optimal operation strategy could be maximized, in particular, during the initial stage of project construction. Furthermore, the commercial software MATLAB was used for programming and calculations. The simulation results indicated that the application of the combined cooling, heating, and power system could significantly improve the cost-effectiveness.

  • 408.
    Diaz-Ramirez, Maryori
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Sebastian, Fernando
    Royo, Javier
    Xiong, Shaojun
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Ash Characterization and Transformation Behavior of the Fixed-Bed Combustion of Novel Crops: Poplar, Brassica, and Cassava Fuels2012In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 26, no 6, p. 3218-3229Article in journal (Refereed)
    Abstract [en]

    New biofuel raw materials for energy pellet production are now being studied as potential energy sources for the heating market. Because of the complexity of the chemical and physical properties of novel fuels, such as some agricultural residues and energy crops, the study of their ash-related aspects is crucial for the sustainable development of this potential energy sector. Ash fractions formed during fixed-bed combustion of different pelletized novel crops; i.e., two Mediterranean crops (one herbaceous, brassica, and one woody species, poplar) and three Chinese cassava stems (cassava species from three different Chinese regions), and three Chinese cassava stems (cassava species from three different Chinese regions), were characterized, and their formation paths assessed in this study. Special emphasis was placed on elucidating the role of major ash-forming elements in the fractionation and transformation behavior, leading to the formation of bottom ash, deposits, and particulate emissions (fine and coarse ash particle fractions) on the basis of experimental data. In the Mediterranean fuels, the predominant ash fraction obtained was bottom ash, mainly characterized by silicates. Phosphates were found to be the main crystalline phases in the Chinese fuels. The slagging tendency was low for all of the fuels, although more significant for the cassava species under the studied conditions. Further, combustion of the studied Chinese energy crops resulted in a considerably finer particle fraction compared to the Mediterranean fuels. Deposits and particulate matter were dominated by K-sulfates as well as K-chloride in all fuels (except poplar), with the occurrence of K-phosphates for cassava pellets. Overall, this study showed fundamental differences in ash transformation behavior during combustion of P-rich fuels (i.e., cassava mixtures) compared to Si-rich fuels (i.e., poplar and brassica mixtures). Of major importance is the experimental verification of the higher thermodynamic stability of phosphates in relation to silicates. Furthermore, in P-rich fuels at high (K + Na)/(Ca + Mg) ratios, a significant degree of alkali metal volatilization occurs, which forms larger amounts of particulate matter, whereas this ratio has no/low effect in Si-rich fuels at high alkali metal ratios.

  • 409.
    Dion, Claude
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Demirgok, Berk
    Dept. Mechanical and Aerospace Engineering, West Virginia University, 26506 Morgantown, USA.
    Akkerman, Vyacheslav
    Dept. Mechanical and Aerospace Engineering, West Virginia University, 26506 Morgantown, USA.
    Valiev, Damir
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Bychkov, Vitaly
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Acceleration and Extinction of Flames In Channels With Cold Walls2015In: Proceedings of the 25th International Colloquium on the Dynamics of Explosions and Reactive Systems / [ed] M.I. Radulescu, 2015Conference paper (Refereed)
  • 410.
    Dion, Claude
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Demirgök, Berk
    Dept. Mechanical and aerospace Engineering, West Virginia University.
    Akkerman, Vyacheslav
    Dept. Mechanical and aerospace Engineering, West Virginia University.
    Valiev, Damir
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Bychkov, Vitaly
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Flames in channels with cold walls: acceleration versus extinction2015In: MCS 9, 2015Conference paper (Refereed)
    Abstract [en]

    The present work considers the problem of premixed flame front acceleration in microchannelswith smooth cold non-slip walls in the context of the deflagration-to-detonationtransition; the flame accelerates from the closed channel end to the open one. Recently, anumber of theoretical and computational papers have demonstrated the possibility of powerfulflame acceleration for micro-channels with adiabatic walls. In contrast to the previous studies,here we investigate the case of flame propagation in channels with isothermal cold walls. Theproblem is solved by using direct numerical simulations of the complete set of the Navier-Stokes combustion equations. We obtain flame extinction for narrow channels due to heat lossto the walls. However, for sufficiently wide channels, flame acceleration is found even for theconditions of cold walls in spite of the heat loss. Specifically, the flame accelerates in thelinear regime in that case. While this acceleration regime is quite different from theexponential acceleration predicted theoretically and obtained computationally for theadiabatic channels, it is consistent with the previous experimental observations, whichinevitably involve thermal losses to the walls. In this particular work, we focus on the effectof the Reynolds number of the flow on the manner of the flame acceleration.

  • 411.
    Dolvander, Linus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Styrsystem till bromsvagn: Avsedd för klimatiska tester av militärfordon2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project is part of a prestudy of a hydraulic brake wagon designed to be towed for endurance testing of military vehicles. This report presents the design of the control system for the brake wagon. It describes the programming of a control system for a hydraulic system developed in parallel, the search of potential component suppliers, and the compilation of a failure analysis. The result was a control system programmed in CODESYS, with an operator interface, a block diagram of the system and a Failure Mode Effect Analysis. The conclusion is that a prototype could be built based on this work but a modification of the system and certain risks should be considered.

  • 412. Dong, Jiankai
    et al.
    Zhang, Long
    Deng, Shiming
    Yang, Bin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Huang, Shun
    An experimental study on a novel radiant-convective heating system based on air source heat pump2018In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 158, p. 812-821Article in journal (Refereed)
    Abstract [en]

    Air source heat pump (ASHP) has been widely applied to many parts of the world due to its simple structure and low initial cost. To save energy consumed for spacing heating and enhance the indoor thermal environment, improving the performances of ASHP has become one of the research focus in the relevant field. Currently, the most conventional heating terminal of ASHP system for spacing heating is finned tube heat exchanger coupled with air fan, which may cause strong draught sensation and dry eye problem and make users feel uncomfortable during convective heating. On the other hand, radiant heating is attracting more and more attention due to its comfortable indoor thermal environment. In this paper, a novel radiant-convective heating terminal was presented and coupled into an ASHP system. Both the operating characteristics and heating performances of the novel system were experimentally investigated. The experimental results showed that the novel system took about 28 min to enter a steady operating stage, during which the radiant panel surface temperature and outlet air temperature for the novel heating terminal, and COP of the novel system were 40.9 degrees C, 32.1 degrees C, and 3.11, respectively, under a standard heating condition. In addition, all parameters mentioned above saw a linear increase when the outdoor air temperature increased from -4.0 to 10.0 degrees C, and their respective rising rates were 0.41 degrees C, 0.28 degrees C and 0.04 per increased outdoor air temperature. Furthermore, the experimental results also demonstrated that adjusting the indoor air flow rate could effectively allocate the amount of heat generated by different heat transfer modes, which may have significant effects on the indoor thermal environment.

  • 413.
    Dong, Xiaowei
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Initial concepts to develop a semi-autonomous operator support technology for operating a novel forestry machine2018Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Forestry machines have the power to lift heavy logs, but they are not so smart at providing information, or help operators perform better work. The main reason to this problem is the low level of technology applied to forestry machines, which has not changed so much since the forestry machines were first introduced in the 1960’s. But starting 2013, machines manufacturers got inspired by developments in the automation and robotics industry, several of new technologies have been developed in the market - computerized hydraulics, feedback controllers for vibration damping, sensor-based motion control systems, improvements in mechanical design, smart suspension controller, etc. Largely, this development is attributed to better hardware and software developed during the last decade by researchers of Scandinavian institutes.

    In this thesis, we introduce a new type of forestry machine, the harwarder, which can perform the work of two machines (harvester and forwarder) by a single one. The forwarder is a forestry vehicle that carries big felled logs. The harvester is a type of heavy forestry manipulator employed in cut-to-length logging operations for felling, and bucking trees. Both the manipulator and vehicle should work synchronized to get the best out of this design. To benefit out of its design, in the first part of thesis we will analyze the kinematics and dynamics of machine, and design a time optimal coordinated motion via virtual holonomic constraints, to solve a particular task of forestry crane. The second part consists on applying optimization to reduce energy consumption during the motion.

    Result of thesis work: 1) By using coordinated motion, consequently the energy consumptions are drastically reduced comparing to traditional motion of the crane. 2) By applying optimization, the energy efficiency is improved.

  • 414.
    Dopson, Mark
    et al.
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Halinen, Anna-Kaisa
    Rahrmen, Nelli
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Sundkvist, Jan-Eric
    Riekkola-Vanhanen, Marja
    Kaksonen, Anna H.
    Puhakka, Jaakko A.
    Silicate mineral dissolution during heap bioleaching2008In: Biotechnology and Bioengineering, ISSN 0006-3592, E-ISSN 1097-0290, Vol. 99, no 4, p. 811-820Article in journal (Refereed)
    Abstract [en]

    Silicate minerals are present in association with metal sulfides in ores and their dissolution occurs when the sulfide minerals are bioleached in heaps for metal recovery. It has previously been suggested that silicate mineral dissolution can affect mineral bioleaching by acid consumption, release of trace elements, and increasing the viscosity of the teach solution. In this study, the effect of silicates present in three separate samples in conjunction with chalcopyrite and a complex multi-metal sulfide ore on heap bioleaching was evaluated in column bioreactors. Fe2+ oxidation was inhibited in columns containing chalcopyrite samples A and C that leached 1.79 and 1.11 mM fluoride, respectively but not in sample B that contained 0.14 mM fluoride. Microbial Fe2+ oxidation inhibition experiments containing elevated fluoride concentrations and measurements of fluoride release from the chalcopyrite ores supported that inhibition of Fe2+ oxidation during column leaching of two of the chalcopyrite ores was due to fluoride toxicity. Column bioleaching of the complex sulfide ore was carried out at various temperatures (7-50 degrees C) and pH values (1.5-3.0). Column leaching at pH 1.5 and 2.0 resulted in increased acid consumption rates and silicate dissolution such that it became difficult to filter the leach solutions and for the leach liquor to percolate through the column. However, column temperature (at pH 2.5) only had a minor effect on the acid consumption and silicate dissolution rates. This study demonstrates the potential negative impact of silicate mineral dissolution on heap bioleaching by microbial inhibition and liquid flow.

  • 415.
    Dopson, Mark
    et al.
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Lövgren, Lars
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Silicate mineral dissolution in the presence of acidophilic microorganisms: implications for heap bioleaching2009In: Hydrometallurgy, ISSN 0304-386X, E-ISSN 1879-1158, Vol. 96, no 4, p. 288-293Article in journal (Refereed)
    Abstract [en]

    Silicate minerals are found with sulfide minerals and therefore, can be present during heap bioleaching for metal extraction. The weathering of silicate minerals by chemical and biological means is variable depending on the conditions and microorganisms tested. In low pH metal rich environments their dissolution can influence the solution chemistry by increasing pH, releasing toxic trace elements, and thickening of the leach liquor. The amenity of five silicate minerals to chemical and biological dissolution was tested in the presence of either ‘Ferroplasma acidarmanus’ Fer1 or Acidithiobacillus ferrooxidans with olivine and hornblende being the most and least amenable, respectively. A number of the silicates caused the pH of the leach liquor to increase including augite, biotite, hornblende, and olivine. For the silicate mineral olivine, the factors affecting magnesium dissolution included addition of microorganisms and Fe2+. XRD analysis identified secondary minerals in several of the experiments including jarosite from augite and hornblende when the medium contained Fe2+. Despite acidophiles preferentially attaching to sulfide minerals, the increase in iron coupled with very low Fe2+ concentrations present at the end of leaching during dissolution of biotite, olivine, hornblende, and microcline suggested that these minerals supported growth. Weathering of the tested silicates would affect heap bioleaching by increasing the pH with olivine, fluoride release from biotite, and production of jarosite during augite and hornblende dissolution that may have caused passivation. These data have increased knowledge of silicate weathering under bioleaching conditions and provided insights into the effects on solution chemistry during heap bioleaching.

  • 416.
    Drugge, Niclas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Evaluating the use of mobile Augmented Reality as a digital communication tool2018Independent thesis Advanced level (degree of Master (Two Years)), 300 HE creditsStudent thesis
    Abstract [en]

    For over a century, mankind has been dreaming about technologies that combined reality with the wonders of the virtual world. Nowadays, Augmented Reality (AR) is doing just that, and with an emergence of AR in many new fields, there is reason to believe that it will be a widely used communication tool in the future. However, it is important to know what the benefits and disadvantages of AR is, not just from a user perspective, but also from a developer perspective. Therefore, a literature study on human communication and AR was performed in this thesis, along with the development of a mobile AR application, and also two surveys inquiring about the attitudes regarding AR present in people in the communications industry. The literature study showed that AR can help people process information by increasing the visualization aspect, and that it is a durable technology to the changes that languages go through. There is, however, a risk that AR can be an excluding technology, especially for older people, and the application development process also showed that there are compatibility issues to consider before developing.

  • 417.
    Dudenhöfer, Dennis
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    En kostnadsjämförelse mellan hyrd och köpt utrustning2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the swedish construction business, most contractors rent their equipment from renting companies. There are different reasons for that, the most significant reason being that companies do not want to tie up capital. Rekab Entreprenad AB is one of those companies. Andreas Nilsson, project manager at Rekab, now wants to investigate which is more profitable, buying own equipment or renting. The purpose of this study perform a case study for Rekab Entreprenad AB in Umeå. Using websites of companies that are partners with Rekab, prices for buying different equipment were compared to rent prices. Different factors like rent for storage, transportation and insurance were also taken into consideration. Also suggestions were given for more environment-friendly equipment handling. The economic result is divided into two parts: the individual cost for every piece of equipment and general costs. Examples for general cost are: rent for storage, insurance, transportation and other factors that are not dependent on quantity of equipment. Results for individual cost of every equipment varies, but generally the cost for buying machines is one fourth of the cost for renting. The . Also the general cost is to be added to that number. A factor to take into account is storage rent, which is already being paid by Rekab, and therefore is not an extra cost when buying own equipment. In conclusion, the profitability in buying eqipment depends on the equipments quantity. In Rekabs case, according to this study, buying equipment is much more economically profitable than renting equipment. A profitability as high as the study suggests must be questioned by the fact that Rekab is still renting equipment. That question can be explained with hidden costs, which often are hard to put a pricetag on. A discussion about these hidden costs is presented in the discussion section.

  • 418.
    Dyrlind, Johan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Sänkning av fjärrvärmetemperaturen för ökad elverkningsgrad2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Umeå Energi AB provides the majority of Umeå municipality with district heating. In the central district heating system there are two power plants that produce both heat and electricity from waste, Dåva 1, and biofuels in the form of wood chips and peat, Dåva 2.

    Combined Heat and Power (CHP) plants will normally have a better electrical efficiency if district heating supply temperature is lowered; therefore the possibility and profit potential of lowering the supply temperature from the CHP plants and alsothe other heat-producing plants in the network have been investigated.

    The purpose of this thesis has been to investigate the possibility of lowering the supply temperature in Umeå Energi´s district heating network and to calculate the possible income increases if it is done.

    To be able to lower the supply temperature without reducing the heat production, the flow in the district heating network must be increased so that the same amount of heat can be delivered. This thesis examined both the current situation including the current flow constraints and the new constraints that will apply when an additional booster station is plugged into the district heating network.

    A linear fit of the measured values of the flow temperature and the alpha value, the ratio of produced electricity and heat produced, shows that lowering the supply temperature increases the alpha value for both CHP plants according to the equations below:

    α1=0,5834−0,0029∗TF   α2=0,7136−0,0026∗TF

    In addition to the alpha value heat losses from the distribution network also changes with a change in supply temperature.

    A control curve is currently controlling the supply temperature as a function of outdoor temperature, but according to measured values, the control curve is not followed during the majority of the time. This is taken as a further indication that the control curve for the supply temperature should be revised.

    Linked to district heating network is an absorption refrigeration unit that requires a supply temperature of at least 95°C during the summer. When the absorption refrigeration unit is not in operation, the requirement of the flow temperature is 75°C. It should also be investigated how much profit could be made if the absorption chiller did not require a higher supply temperature.

    All calculations have been performed based on measured data from the years 2010 and 2011, data that is considered to be representative also for future years. New control curves have been recommended based on the calculations for optimizing profit with the measured data from the years mentioned above years, calcaulations for the increased income using these control curves have also been done.

    With the current operating condition the potential profit is calculated to be around three million Skr per year with an additional two million in profit if the chiller does not require a higher temperature during the summer.

    With a new booster station the estimated profit differs quite a lot between the years with around 17 million Skr of potential profit in 2010 and 11 million Skr in 2011. The profit if the chiller doesn’t require a higher temperature is basically unchanged, about two million Skr.

    The conclusion of the thesis is that it is both possible and profitable to change control curve and use a lower supply temperature. Since 2010 was a unusually cold year and 2011 was a unusually warm year the calculated profits are considered representative also for coming years. The maximum flow with a new booster station is based entirely on theoretical values and should be considered as more insecure then the other results. It is recommended to try the control curves from this thesis in the production and evaluated the profit in a real situation.

  • 419.
    Dyvik, Karl-Johan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Jämförelse av trä-, betong- och stålstomsystem för flerbostadshus i Leksand2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There are many different variants of structures for a framework system. Skoglunds Bygg has used many different frame systems over the years and they now want these evaluated and compared to get a result on what has been the most profitable and time-efficient designs. By using a reference house, the goal is to study and compare different frame systems that Skoglunds Bygg has used in previous projects, but also to compare some new solutions that they are interested in. As a conclusion to this comparison, Skoglunds Bygg wants to get a "Skoglund model", which consists of the most profitable and time-efficient design solutions.

     

    To be able to carry out this comparison, a literature study was first carried out in order to gain a deeper understanding of the various designs and the computer program to be used. Then Skoglunds Bygg reported which designs they wanted to compare. When this was done, the computer program BidCon was used to compare these constructions with regard to time and costs. This eventually resulted in a "Skoglund model".

     

    The result shows that the wooden timber frame with a wooden facade are the cheapest construction, while the fastest construction is curtain walls with wood façade.

    For load-bearing partition walls, the result shows that the concrete shell wall is the cheapest and fastest alternative in this particular study.

    For the framing of joists floor, the result shows that the concrete flooring DalaDekk is the cheapest alternative, while the hollow core flooring in concrete is the fastest construction to produce. 

     

    “The Skoglundsmodel” consists of the following:

    • Load-bearing external walls - Curtain walls with a wood facade
    • Load-bearing partition walls - Concrete shell walls
    • Floor layers – Flat concrete base 
  • 420.
    Eckerdal, Cecilia
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Solcellsanläggningar i LEVA i Lysekils distributionsnät2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Marknaden för solceller har ökat kraftigt i Sverige de senaste åren. Tillväxten utgörs både av en ökning av mikroanläggningar hos privathushåll och en ökning av stora anläggningar. De tre senaste åren har även stora kommersiella anläggningar som har försäljning av elproduktion som främsta syfte tagits i drift.

    LEVA i Lysekil AB är ett kommunalt elbolag som vill undersöka möjligheterna till investering i en eller flera solcellsanläggningar inom Lysekils kommun. Som en del i detta undersöker detta examensarbete tekniska och ekonomiska förutsättningar för investering i solceller, samt vilken påverkan en större solcellsanläggning kan ha på distributionsnätet. Två driftscenarion med anslutning av en 1 MW solcellsanläggning till mellanspänning 10 kV har simulerats i programvaran dpPower. Spänningsförändringar och effektflöden utmed linjen har studerats.

    Systempriset på solcellsanläggningar har minskat kraftigt de senaste åren och bedöms fortsätta minska, dock i en långsammare takt. Stora anläggningar som producerar el till egen förbrukning är idag undantagna från energiskatt, men kan komma att få sämre ekonomiska förutsättningar om nuvarande förslag om energiskatt går igenom. Det finns även en osäkerhet kring hur fastighetstaxeringen av en större solcellsanläggning kommer att bli från 2016. Det statliga stödet till solceller påverkar i hög grad investeringskalkylen, men möjligheten att få stöd vid en ansökan nu bedöms som liten eftersom redan inkomna ansökningar överstiger anslagna medel.

    Vid anslutning av en större solcellsanläggning till mellanspänningsnätet bedöms den största risken vara höga spänningsnivåer när anläggningen producerar full effekt samtidigt som lasten är låg. Risken beror av hur lastuttaget ser ut på linjen, om det finns andra produktionskällor som matar in effekt samt hur starkt nätet är. Inför en projektering bör även driftfallet med reservmatning undersökas eftersom spänningsförändringarna kan se helt annorlunda ut då jämfört med normaldrift.

    Växelriktarna från solcellsanläggningen ger ut övertoner av främst tredje och femte ordningen. Det interna kabelnätet som finns i en solcellsanläggning kan påverka resonansfrekvenser i nätet när anläggningen ansluts till överliggande nät. För att minimera risken för resonans som förstärker övertonerna och sprider dem vidare på nätet kan resonansberäkningar behöva göras.

    Solcellsanläggningar i nätet kan minska nätförlusterna eftersom elproduktionen sker närmare förbrukningen. För att göra en analys av hur nätförlusterna ändras behöver produktionsmönster och förbrukningsmönster på linjen inkluderas. Beräkningar där lastuttag varieras tillsammans med olika stor produktionsinmatning på linjen kan ge en första bild av hur effektflödet och därmed förlusterna kommer att se ut. 

  • 421.
    Edberg, Erik
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Chassi För Bromsvagn: Bromsvagn avsedd för klimatiska tester för fordon2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report presents my thesis for a Bachelor of Science in Mechanical Engineering at Umeå University. The thesis is part of a pilot study for a brake trailer, that BAE Systems Hägglunds AB have considered using for vehicle testing at their testing department. The pilot study has been done together with three other students, that have worked with integrated parts. Strength of materials, Computer-Aided Design(CAD) and Finite Element Method(FEM) have been the main theory of this report. The implementation describes how the chassis was designed in CAD and how strength analyses were performed by hand and with FEM. A failure modes and effects analysis was made with the purpose of analysing what could go wrong with the design.Quotation of different modelled components have been investigated together with possible suppliers. The calculated effective stress that emerged in a section of the chassis loading platform was compared with the FE-analyses. The difference in stress was not significant and therefore it was deemed within reasonable values. The report concludes with suggestions for continued work.

  • 422.
    Edler, Jenny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Drying biosludge with a high-velocity cyclone dryer2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sludge disposal is a worldwide problem due to increasing volumes and respective environmental regulations. Currently the most common ways to dispose sludge are agricultural use, disposal in landfills, incineration and sea dumping. By drying sludge volumes can be decreased and the respective heating value increased. Sludge mainly originates from wastewater treatment. The Swedish pulp and paper mills produce approximately 400 000 - 500 000 metric tons of dry sludge each year. This includes roughly 60 000 metric tons of dry biosludge which mainly consists of bacteria and is difficult to dry due to high amounts of intercellular water. New drying methods for biosludge are hence needed. The purpose of this project is to investigate the possibility to dry biosludge in a high-velocity cyclone dryer since the technology has been shown to be able to handle sticky materials. The sludge used in this project originates from the biological wastewater treatment at the pulp and paper mill Metsä Board Husum, located in Husum, Sweden.

    The achieved dry matter contents and the specific energy consumption have been examined and compared with established drying methods.  Design of experiments has been used during the trials for optimizing the information attained from a limited number of trials including effects of inlet air temperature, sludge feeding rate and recycling of drying air. The respective factors were varied in three steps and relevant temperature, pressure, humidity, flow and material mass values were measured for analysing the process. 

    Models for attained dry matter content, specific energy consumption (total and of the fan), removed water and fan power were developed and had high statistical significance. The models showed that sludge dry matter content up to 80% could be achieved. The total specific energy consumption was over 1.6 kWh/kg H2O, which is higher than for established drying methods, but the specific energy consumption of the fan was as low as 0.7 kWh/kg H2O. The specific energy consumption of the fan was used to approximate dryer operation with excess heat during which it could compete with all established drying methods.

    A case where the excess heat available at Metsä Board Husum would be used to dry generated biosludge was investigated and supported a need for a priority order between maximizing sludge dry matter content and minimizing specific energy consumption of sludge drying. If sludge dry matter content is prioritised alternative drying methods may prove more suitable.

    To attain a better understanding of the high-velocity cyclone dryer and drying of biosludge the evaporation energy of sludge at different dry matter contents, the effects of various sludge inflow temperatures and the effect of fan rotation speed should be included future investigations.

  • 423.
    Edling, Pontus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Enkel UV-absorptionsfotometer för absorbansmätning i medicinska prover2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In laboratory medicine there is equipment such as the spectralphotometer that can measure absorption in a solution to determine the concentration of proteins, amino acids and the like. This is an often expensive equipment and often not readily available. The Department of Biomedical Engineering - Research and Development (BE-RD) at University hospital of Umeå has been asked to investigate the possibilities of constructing a simple and cheap UV-absorption photometer. The aim of this study was to produce a functioning prototype of a UV-absorption photometer that would be able to measure the concentration of SAICA-r and S-Ado which occurs in the urine of the rare disease Adenolosuccinate lyase deficiency (ASL). For this bachelor thesis, adenosine triphosphate (ATP) was chosen as measuring substance, since ATP is a stable protein which is soluble in water and which can be frozen and defrosted. It also has an absorbance spectra which is very close to SAICA-r and S-Ado. A functioning prototype of the UV-absorption photometer has been developed. The prototype demonstrates a good linearity(R2 = 0.9956) for concentrations between 0-50 mg/L and a high accuracy for absorbance σ=0.0006. With these results, the prototype is judged to be capable of measuring the content of SAICAr and S-Ado in a urine sample.

  • 424.
    Edlund, Olov
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Svikt i bjälklag2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    For wooden joists with long spans to meet the requirements with respect to springiness or deflection caused by a static midpoint load, composite action, load sharing and possibly frame action need to be used. The elements developed and produced by Lättelement AB are designed to include these type of actions.

    In this thesis work, the vertical deflection of Lättelement AB’s floor elements of different designs, are evaluated. The deflection criteria according to Eurocode 5 and the Swedish standards is then used to determine the acceptability of the different floor designs. A generalized program has been developed to calculate the deflection, where different parameters such as material quality, geometrical dimensions, cross-section properties and span lengths easily can be varied. Using this program, the behavior and and design of the floor elements can more easily be improved.

    A parameter study has been conducted to evaluate the influence of varying the directions of the components and the effect of the frame action.

    Most of Lättelement AB’s floor designs pass the criterion for springiness due to the fact that composite action, load sharing and frame action can be utilized.

  • 425.
    Edman, Agnes
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Optiska Time-of-Flight sensorer kan användas för att mäta steghöjd och stegbredd under gång: En utvärdering av sensorer i en laborativ och reell miljö2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In some medical cases it is of interest to study a persons gait. This can be done in several different ways, both simple and advanced. A project has been done at the department Medicinsk Teknik - Forskning och Utveckling at the University Hospital of Umeå. In that project a system with optical triangulation sensors was created to easily measure a persons step width and step height. It was found that the sensors had limitations, in particular with sample frequency, and it was therfore of interest to test new sensors for this application. The goal with this project was to evaluate two sensors, VL53L0X and VL6180, and investigate if they can be used to measure step width and step hight. A system was built to communicate with and read data from the sensors. The sensors were then tested both in a laborative and real environment. With good reflection both VL6180 and VL53L0X show good precision in the range of interest. The sensors has the resolution of millimeters. VL6180 works better at really close distances but has a much shorter maximum range, about 18 cm, and lower maximum sample frequency, under 43 Hz. VL53L0X was tested up to 70 cm and 50 Hz. To be able to measure step width from the ankle, a very high sample frequency is needed to get the right amount of data when the legs pass eachother. If the sensors can be used in that way has not been confirmed. When placed higher on the persons leg, VL6180 can be used to measure step width and VL53L0X can be used to measure both step width and step height. 

  • 426.
    Edo Gimenez, Mar
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Energy Engineering, Department of Engineering Sciences & Mathematics, Luleå University of Technology, Luleå, Sweden.
    Gao, Qiuju
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Persson, Per-Erik
    Jansson, Stina
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Fate of metals and emissions of organic pollutants from torrefaction of waste wood, MSW, and RDF2017In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 68, p. 646-652Article in journal (Refereed)
    Abstract [en]

    Torrefaction of municipal solid waste (MSW), refuse-derived fuel (RDF), and demolition and construction wood (DC) was performed at 220°C and a residence time of 90 min in a bench-scale reactor. The levels of toxic polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) contained in emission from the torrefaction process were evaluated. In addition, main ash-forming elements and trace metals in the raw feedstock and char were determined. The use of MSW in fuel blends with DC resulted in lower PCDD and PCDF emissions after torrefaction, compared with the RDF blends. The migration of chlorine from the feedstock to the gas phase reduces the chlorine content of the char which may reduce the risk of alkali chloride-corrosion in char combustion. However, trace metals catalytically active in the formation of PCDD and PCDF remain in the char, thereby may promote PCDD and PCDF formation during subsequent char combustion for energy recovery; this formation is less extensive than when the feedstock is used.

  • 427.
    Edström, Linnéa
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Armbandsbaserad pulsoximetri: Ett egenkonstruerat system med reflekterande teknik och jämförelse mot traditionell mätteknik vid normal och nedsatt hudtemperatur2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this report a low-cost, portable and wearable design of a new system with reflective technologyfor pulse oximetry is presented. The work has been executed as a project, including electronics construction, software development, a design of the embedding for the prototype and continuous tests of both the hardware and software during the work in progress.

    The result of this work is a prototype system for pulse oximetry. The system can communicate through Bluetooth wireless interface with a PC, laptop or smartphone which supports Bluetooth 4.0. The measurements are shown in real time on a PC/laptop/smartphone. The software is written in mbed with the language C++ for the microprocessor. The project demands different technical skills like signal processing, programming, electronic design and microprocessors. Over all the project is a good introduction for medical technology and a basis for electronic engineers.

    The purpose and goal with the thesis is considered to be reached for the most part and further testing and development of the product is possible.

  • 428.
    Edström, Mikael
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Erfarenhetsåterföring mellan olika aktörer inom byggbranschen2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Experience feedback is an important tool to save time, money and to develop the construction industry. Many companies knows this, but despites these important advantages, experience feedback is rarely used. Former studies has shown that it, among others, can be explained by narrow time constraints and bad commitment. This study is made in cooperation with a company who is specialized in industrial building construction, this company as well other entrepreneurs is the case study in this bachelor thesis. 

     

    The purpose with this study is to illustrate the importance of the subject and the various earnings a company can make when they practice good experience feedback. As well as analyze how experience feedback works in collaboration between different actors, and with the help of the manufacturing industry apply different techniques to reduce waste and mistakes. 

     

    The study use four methods to collect data. These are questionnaires, interviews, observations and a literature study. All these methods has co-operated with a result that shows that different entrepreneurs agrees that experience feedback should be used. All the participants in the study believes that there are gains in time and money when it´s used. An explanation to why it´s not applied is because of narrow time constraint, which in turn is somewhat paradoxal because you can save time by using it. It also turned out in collaboration with other entrepreneurs that they don’t always share experiences because there may be financial profits in keeping the information for themselves, where the effects of modification and supplementary work also can counteract so that it´s not applied. 

     

    Experience is expensive, nor is it cheaper in a conservative industry. But there is hope, the people in it want change. There are already existing tools available and these are Lean Production, quality systems and working towards a processoriented organization. 

  • 429.
    Edström, Oskar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstruktion av automatisk monteringscell2013Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport presenterar ett examensarbete som handlar om en konceptstudie för en monteringscell. Examensarbetet har genomförts av Oskar Edström, student inom maskinteknik på Umeå Universitet, under våren 2013.

    Syftet med arbetet har varit att utveckla en lösning för hur en bussning, som används i Volvos lastvagnar, skall monteras ihop automatiskt i en produktionscell. Arbetet har genomförts i samarbete med uppdragsgivaren HT-Svarv i Kalix

    För att definiera befintliga problem med dagens konstruktion har förstudier, med kartläggning av företagets behov, genomförts. HT-Svarv vill ändra hur bussningen monteras ihop. Detta för att få kortare operationstid under processen och minska behovet av personal vid montering. Före automatisering monterades bussningen ihop manuellt.

    Koncept har genererats i en dialog tillsammans med uppdragsgivaren där man diskuterat olika lösningar för konstruktionen. Koncepten har sedan utvärderats och sållats fram. Vid modellering för koncepten har CAD-programmet Solid Works använts.

    Arbetet resulterade i en lösning där monteringscellen är uppbyggd i tre stycken operationer samt med en efterföljande kontrollstation. För vidareutveckling av valt koncept bör fokus ligga på produktionsoptimering och tester av funktionsprototyper.

  • 430.
    Edström, Urban
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Centrum för medicinsk teknik och strålningsfysik.
    Nackvinkelmätningar vid thoraxoperation: Kan prismaglasögon underlätta arbetet för operationssjuksköterskor?2017Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
  • 431.
    Edström, Urban
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Nackvinkelmätningar vid thoraxoperation: Kan prismaglasögon underlätta arbetet för operationssjuksköterskor?2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
  • 432.
    Edvardsson, Jonas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Nötningsrigg för länksystem i skogsmaskinsband2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been executed at the forestry machine track manufacturer Olofsfors AB and has been aimed at development of a rig for simulation of the wear that occurs in the linkage of Olofsfors AB forestry machine tracks. The problem is that link hooks in the tracks wears out first, often several times faster than other components. Olofsfors AB want to be able to test this wear in a controlled environment. The purpose of the wear rig is to distinguish what type of wear that is in effect as well as be able to optimize materials for Olofsfors AB: s products.

     

    The project began with an pilot study of different types of relevant wear and different types of complete methods of wear measurement and simulation to better understand the problem. After this a market screening of existing machines and rigs that could be of interest was done. The project continued with creation of concepts of wear rigs and methods of wear. After a selection process the project proceeded with one concept to a 3D prototype.

     

    From the market screening it could be found that the market is very thin with few suppliers. Their products are relatively expensive and need specially made test samples. The recommendation to Olofsfors AB will therefore be to construct a rig themselves. The market screening could be used by Olofsfors AB as a basis if they decide to expand their test activity in the future. 

     

    The project reached the overall goals and delivered a prototype that passes the set demands. This means that the project is basically ready to move on to construction of a physical wear rig. There are still some problems to overcome but these will be easiest to solve during the construction phase. 

  • 433.
    Edvinsson, Emil
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Masonites flexibla byggsystem - Utformning av skarvbeslag för hopfogning av prefabricerade väggelement2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Masonites flexibla byggsystem, är ett byggsystem utvecklat av Masonites Beams AB för flervåningshus, bostäder och kontor i trä.  System är anpassat så att det i största möjliga utsträckning går att använda sig av prefabricerade element direkt från fabrik, för att sedan hopfogas med mekaniska förband på byggarbetsplatsen.

    Masonites förslag på en infästning mellan bärande väggar är utformad som en montagedubb vilken förs ned i ett hål i underliggande väggelement. Montaget av dubben fungerade inte önskvärt, och det finns tveksamheter i montagedubbens förmåga att ta upp vindinducerande krafter.

    Examensarbetet syftar till att utforma och dimensionera ett nytt väggbeslag till Masonites flexibla byggsystem där snabbt montage av beslaget är viktigt. Iden är att såga en kontinuerlig slits i väggelementen som man sedan fäster plåtar som skruvas fast i det övre- respektive det undre väggelementet. Skruven som används är en självborrande skruv för att slippa förborrning av plåten och väggelementet.

    Reglerna i Eurokod 3 och 5 ligger till grund för beräkningarna av beslaget och lastnedräkningen av ett 8-våningshus är enligt BKR. Lämplig indata till lastnedräkningen gjordes i samråd med erfaren konstruktör och inblandade i MFB från Masonite. Slutresultatet blev ett förslag med en plåt med minsta dimensionen 250x200x3 S275 och Adjufix karmskruv från Kartro.

  • 434.
    Edvinsson, Joakim
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Webifiering av BidCon2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Consultec är ett ledande företag inom utveckling av IT-verktyg och tjänster anpassade för bygg- och installationsbranschen. De har identifierat ett behov från deras kunder att se över möjligheterna att göra ett av deras verktyg mer lättåtkomligt via en webb-applikation.Målet med detta projekt är att utvärdera om det är möjligt att publicera ett redan existerande program på en hemsida samt att ta fram en prototyp. Hemsidan som tagits fram visar ett grovt exempel över hur den färdiga produkten skulle kunna se ut.

  • 435.
    Egelstig, Martin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstruktiv utformning av vikplog2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project is about investigation and improvement of a V-plow for the company Swekip. A V- plow is used for snow removal but this product has been found to have deficiencies in its construction, breaking down and not living up to the desired objectives. This is because the product is ordered from a company in China where they have some problems with understanding the purpose of the plow.

    Initially the existing plow is investigated, all the shortcomings set out and examined, what is wrong and what needs improvement?

    When the solutions were done they were evaluated and examined that they actually live up to the desired requirements.

    This assignment is a pure construction project where the majority is implemented in CAD, where models are developed and FE analyses are carried out. But the project also includes a feasibility study, idea study and hydraulic design.

    The results are presented in the form of a CAD model and associated drawings that will serve as the manufacturing basis for the new V-plow. The finished model is based on the original plow but with many new enhancements to remedy the deficiencies the plow had. 

  • 436.
    Ehatisham-ul-Haq, Muhammad
    et al.
    Faculty of Telecom and Information Engineering, University of Engineering and Technology, Taxila, Punjab, Pakistan.
    Awais Azam, Muhammad
    Faculty of Telecom and Information Engineering, University of Engineering and Technology, Taxila, Punjab, Pakistan.
    Naeem, Usman
    School of Architecture, Computing and Engineering, University of East London, United Kingdom.
    Ur Rèhman, Shafiq
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Khaild, Asra
    Department of Computer Science, COMSATS Institute of Information Technology, Wah Campus, Pakistan.
    Identifying smartphone users based on their activity patterns via mobile sensing2017In: Procedia Computer Science, ISSN 1877-0509, E-ISSN 1877-0509, Vol. 113, p. 202-209Article in journal (Refereed)
    Abstract [en]

    Smartphones are ubiquitous devices that enable users to perform many of their routine tasks anytime and anywhere. With the advancement in information technology, smartphones are now equipped with sensing and networking capabilities that provide context-awareness for a wide range of applications. Due to ease of use and access, many users are using smartphones to store their private data, such as personal identifiers and bank account details. This type of sensitive data can be vulnerable if the device gets lost or stolen. The existing methods for securing mobile devices, including passwords, PINs and pattern locks are susceptible to many bouts such as smudge attacks. This paper proposes a novel framework to protect sensitive data on smartphones by identifying smartphone users based on their behavioral traits using smartphone embedded sensors. A series of experiments have been conducted for validating the proposed framework, which demonstrate its effectiveness.

  • 437.
    Eilertsen, Svein Morten
    et al.
    Bioforsk Nord Tjøtta.
    Karlsson, Johannes
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Electronically sensors system to warn drivers if a reindeer is close to the road or the railway2014In: Nordic Association of Agricultural Scientists: NJF Report, 2014, Vol. 10, p. 30-30Conference paper (Refereed)
    Abstract [en]

    In Norway, Sweden and Finland approximately 9.000 reindeer are killed every year in traffic accidents (road and railway). In field experiments two different electronically sensor system were used. The purpose is to warn car drivers and railway engineers that reindeer are close to, or on the traffic system, and reduce the numbers of accident. The information system developed by Telespor is based on GPS/GSM radio collars. These collars use SMS to inform that the reindeer are close to the traffic system. In addition to the warning, the reindeer owners get information about the reindeer land use throughout the whole year. The collars are expensive (approx. 250 euros/unit) and need battery change every year. At Umeå University a system based on wireless sensor nodes attached to the reindeer collars is developed. This node will send out a periodic warning radio beacon. On road sticks a warning device will be attached containing a radio receiver and LED flashlights that will warn if a radio beacon is received. To further increase the warning distance it is possible to use communication between the roadside warning devices and let several devices flash their LED lights when a reindeer is detected. The radio collar (approx. 15 euros/unit) will have a theoretical battery life of more than 10 years. The radio range is around 500 meters between the radio collar and the roadside warning device, which is more than sufficient.

  • 438.
    Ek, Karl
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Kalkylmodell för dimensionering av bandtransportörer2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is the result of a final work for a Bachelor Degree in Mechanical Engineering at Umeå University. The project is made for the Swedish mining company Luossavaara-Kiirunavaara Aktiebolag (LKAB). The purpose of the project has been to develop a calculation model that can be used for designing new conveyor belt systems or optimize already installed objects. The program chosen for the calculation model is Microsoft Office Excel. The goal is that the calculation model will minimize the need to hire external workforce in questions concerning conveyor belts.The prioritized variables the calculation model is supposed to be able to handle are mass flow, volume flow, motor power, belt tensions and transition curves. Other variables that can be implemented if time permits are the selection of belt, pulleys, shafts and bearings for the calculated conveyor belt system.During the project the calculation model will be tested against already installed conveyor belt systems. The field studies are supposed to show how accurate the calculated values are compared to the actual ones.The result of the project is a calculation model based on three different calculation books and two manuals from LKAB. The model contains over fifty equations that are calculated immediately after the right variable is inserted into the program. In the fields next to the calculated value, the user can find information about the variable and a reference to the book that the equation is picked up from. The program has preinstalled values for idlers masses and belt weight, however the user can chose to activate the manual function and thus enter other values. The purpose is to leave the program open so the calculation can be based on any manufacturer of belt and idlers. The model is able to handle mass flow, volume flow, motor power, belt tensions, transition curves, belt type based on belt strength, and size on counterweight.Four conveyor belt systems were analyzed during the field study. The technical drawing was used to compare the installed motor power and the required motor power based on the calculations. In all cases, the calculated value was more than 70 % of the installed motor power, which is the minimum relation between the two values according to LKAB standards.During the field study the instantaneous mass flow and corresponding power consumption were analyzed. Thereafter, the mass flow was inserted into the calculation model and the calculated motor power was compared to the measured motor power. The best result gave a margin error of 2 % and the worst result deviated by 22.8 %. No further analyzis regarding the result has been employed. The field study has showed that the measured mass flow was relatively low compared to the value on the technical drawing, meaning that a large amount of capacity is unused. A suggestion for a future study is to investigate if this is a common phenomenon in LKAB and if there is any sustainable solution to optimize the process.

  • 439.
    Ekberg, Mathias
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Hur man gör en instruktionsfilm: - En instruktionsfilm på beställning av VATTENFALL2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Vattenfall Finance and Accounting services contacted media producer Mathias Ekberg because they needed a person that could create a video tutorial for a new method of working when invoicing in SAP.The purpose of the video is to in a simple and instructive manner, through video and audio, demonstrate how to use the new system.The project launched by creating a pre-study. Where among another things, a target audience was presented as men and women in the ages 30 to 65 with mixed experience.The production was partly performed in Berlin where among other things, a narrator for the video was recorded. The editing software used in the production is called Camtasia, which is a program that is adapted for tutorial videos.The result was a six minute long video. Images have been edited using Camtasia and a female narrator is explaining how to use the system.The conclusion of the project is the importance of an elaborate pre-study where the questions, what to do? When to do it? How to do it? And for whom is it done, are answered.If there will be a next time working with tutorial videos, I have concluded things thatcould have been improved. To use more of the functions and tools that Camtasia has to offer is an example of this, and also that the project could have been run morestrictly from my side, in order to avoid delays.The report also contains a theoretical part where important things when recording audio are covered. It is also possible to read about functions and tools in Camtasia that can be used when creating a tutorial video. Information on Vattenfall as a company and SAP can also be found.

  • 440.
    Ekberg, Mathias
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Reality-TV: En fallstudie om SVT Göteborgs produktion av programmet Hjärta för djur2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Media producer Mathias Ekberg has during the spring term worked at SVT Gothenburg. SVT Gothenburg will during this time, for the first time produce an in-house reality production, instead of buying shows from an external production company. The show is called Hjärta för djur (Heart for animals) and tells the story of people who devote their lives to helping animals who have been mistreated.The production is a pilot project and SVT Gothenburg has therefore asked Mathias Ekberg to analyze the workflow and systems that have been used during the production. Mathias Ekberg has taken part in the project as coordinator and logger, which has made it possible to have good insight on the production as a whole.In other words, the following report is a case study on how to produce a reality show from the first idea to the show being delivered. This report will for the most part cover the production phase since Mathias Ekberg will not be able to gather empirical data from the other parts of the production, though these parts have been complemented through interviews.The purpose of this report in to learn more about reality productions and also to review the workflow that SVT Gothenburg has used to produce Hjärta för djur and which benefits and drawbacks it generates.The result of this study is that the workflow is relatively price- and time effective. The recording was compressed to four weeks, which meant that the team on the spot had to direct the reality in order fit the timeframe. Whether or not this had a positive or negative effect on the content is left to the viewer, but from a production point of view; it was a necessity.Most parts of the production were active at the same time which resulted in good communication between the set, editors and the rest of the production.According to most coworkers this workflow should work in theory. In this case the workflow wasn’t followed to 100 percent since it was a pilot project. This resulted in bottlenecks at the contributing editor and loggers. The recommendation is to refine every part of the production and that the editors should possib

  • 441.
    Ekevärn, David
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energikartläggning av Martinsons Trä AB2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This is a report of a master thesis in energy technology and has been done by mapping energy usage of the company Martinsons Trä AB. Furthermore, this thesis is a part of NV Eko. The purpose of the report is to give a wider image of how energy is used at Martinsons sawmill in Bygdsiljum by mapping specifically and especially the use of electricity in this case. Certain priorities were made, from a production view, and parts of the factory were mapped.

    Measurements were made in order to map the usage of electricity, data has been collected and interviews were conducted.

    The results of this work are statistics over the mapped factories due to the usage of electricity in the these, together with a number of suggestions of improvements. Such suggestions were that some machines need an oversight or replacing.

    The use of electricity in the factories handling the raw material saw processing was calculated to be approximately 30 % of the electricity bought yearly. The factories concerned with the refining process use a corresponding 18 % and the drying facility uses 40 % of the totalt electricity yearly. It was also calculated that in total, Martinsons sawmill in Bygdsiljum uses 23 Gwh.

    The investment of a new moisturising system in the second refining factory (4 in total) needs to be looked into. An oversight of the one of the saw processing factories transformer is needed and the feeding of electricity to the second refining factory needs to be separated from said transformer. Above mentioned measurement needs to be done with transformer 11 as well, separating the second from the third refining factory:s feeding.

    Furthermore an oversight and replacing of certain machines within the refining factories is needed and also a more continuous logging of electricity usage should be implemented.

  • 442.
    Eklund, Anders
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biosciences.
    Hallberg, Per
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Lindén, Christina
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Ophthalmology.
    Lindahl, Olof A.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    An applanation resonator sensor for measuring intraocular pressure using combined continuous force and area measurement2003In: Investigative Ophthalmology and Visual Science, ISSN 0146-0404, E-ISSN 1552-5783, Vol. 44, no 7, p. 3017-3024Article in journal (Refereed)
  • 443.
    Eklund, Anders
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Lindén, Christina
    Umeå University, Faculty of Medicine, Department of Clinical Sciences.
    Bäcklund, Tomas
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Andersson, Britt M
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Centre for Biomedical Engineering and Physics (CMTF).
    Lindahl, Olof A
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Centre for Biomedical Engineering and Physics (CMTF).
    Evaluation of applanation resonator sensors for intra-ocular pressure measurement: results from clinical and in vitro studies.2003In: Medical and Biological Engineering and Computing, ISSN 0140-0118, E-ISSN 1741-0444, Vol. 41, no 2, p. 190-197Article in journal (Refereed)
    Abstract [en]

    Glaucoma is an eye disease that, in its most common form, is characterised by high intra-ocular pressure (IOP), reduced visual field and optic nerve damage. For diagnostic purposes and for follow-up after treatment, it is important to have simple and reliable methods for measuring IOP. Recently, an applanation resonator sensor (ARS) for measuring IOP was introduced and evaluated using an in vitro pig-eye model. In the present study, the first clinical evaluation of the same probe has been carried out, with experiments in vivo on human eyes. There was a low but significant correlation between IOP(ARS) and the IOP measured with a Goldmann applanation tonometer (r = 0.40, p = 0.001, n = 72). However, off-centre positioning of the sensor against the cornea caused a non-negligible source of error. The sensor probe was redesigned to have a spherical, instead of flat, contact surface against the eye and was evaluated in the in vitro model. The new probe showed reduced sensitivity to off-centre positioning, with a decrease in relative deviation from 89% to 11% (1 mm radius). For normalised data, linear regression between IOP(ARS) and direct IOP measurement in the vitreous chamber showed a correlation of r = 0.97 (p < 0.001, n = 108) and a standard deviation for the residuals of SD < or = 2.18 mm Hg (n = 108). It was concluded that a spherical contact surface should be preferred and that further development towards a clinical instrument should focus on probe design and signal analysis.

  • 444.
    Eklund, Pauline
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Implementering av ISOBUS på ECU vid Ålö AB2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A serial bus called ISOBUS based on CAN is becoming more and more common in the agriculture and forestry industry. The bus specifies communication between tractors and their implements. Earlier each implement had its own monitor to show its functionalities, which could lead to a lot of monitors in the tractor cabin. ISOBUS requires only one monitor, called VT (Virtual Terminal), regardless of the manufacturer of the implement.

    The aim of this thesis is to implement ISOBUS at Ålö’s ECU (Electronic Control Unit) so that it can present its functionalities to VT. The aim is to integrate a purchased third party commercial ISOBUS library on ECU. The amount of work to achieve ISOBUS compatibility without third party library shall be estimated, and if there is time the task shall also be carried out. An object pool based on Ålö’s existing interface shall be created, where the object pool is the graphical interface shown at VT. A demonstrator of ISOBUS VT shall be done.

    To implement the third party library hardware functions towards the CAN-bus was required. The hardware functions include receiving messages from a buffer and send messages directly on the bus. For the library to be alive and running it had to be initialized and a periodic call to the library had to be done. The result is that the library was implemented on ECU and data flows between ECU and VT.

    To achieve ISOBUS compatibility without third party library the existing protocol on Ålö’s ECU has to be removed by a base support for ISOBUS. Then a last part must be written to achieve full compatibility. Commands that the ISOBUS standard defines between ECU and VT has to be written, and callback functions that is called when VT sends commands to ECU. Management of answers and errors also have to be implemented. ISOBUS compatibility without third party library wasn’t carried out, but the amount of work was estimated and a general description of what has to be done is written. The conclusion is that it requires a lot of work and scrutiny of the standard. The advantage is that you get an insight into how the system works and the ability to influence functionalities yourself.

    The object pool design was based on Ålö’s existing interface. Menu systems was implemented, and a linear bar graph and a meter have the possibilities to show height and angle of the tractor loader bucket. Different ways to show a menu system has been discussed. The result is an object pool with the basic functions for Ålö’s interface, the demonstrator presents these functionalities. The interface for VT can be made quite similar to Ålö’s existing interface, with some differences such as fonts, image quality and menu functions.

  • 445.
    Eklund, Simon
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energiberäkningar på unikt lågenergihus: Beräkningar av elenergibehov, tankar kring självförsörjning och frågor om klimatpåverkan2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    About two years ago Laura and Erik Vidje began building their very own home just outside the city of Umeå. This building project would later turn out to become a unique and well noticed project with many involved and interested parties. The building project involved an entire estate with a residence, guest house, cold storage cellar and a PV (photovoltaic) system, and Laura and Erik were planning on doing as work as possible by themselves. What made this estate so unique was the choice of designing it according to the passive house requirements and at the same time be using unconventional and recyclable building materials, among other things was that the isolating material was going to be entirely made up of straw and the base plate would be made of recycled foam glass. The construction was going to be very well thought through, with large window facing south and a long roof overhang that will protect against insolation during summer but optimizes the insolation during winter. The walls would be built almost one meter thick to make great isolation and the entire building envelope were going to be extremely dense to minimize heat loss, but the most obvious unique attribute about the residence were going to be its round shape. By today the estate is nearly finished, but before a few technical instalments is executed the Vidje couple wanted to know what energy related needs the estate will have and how it will perform relative to official requirements. This specifically turned out to be only positive for them because the estate is now estimated to have a total need of electricity at about 23,1 kWh/m2 Atemp and year, which is almost one third lower than the standard value only for household energy. Also, the BBR-requirement for EPpet (primärenergital) turned out to be more than twice as high as the actual EPpet for the estate, which proves how well thought out the building project is and its high quality. In addition to this there were an interest in learning about knew technologies within sustainable housing and whether it was possible to implement these to their home. An important question to the Vidje couple was the possibilities regarding the PV system combined with a battery storage system. They would want to use as much of their own solar electricity as possible. What this project found out was that the 5 kWp (kilowattpeak) PV system would be able to cover around 70% of the estates yearly electricity needs, but that they would only be able to personally use no more than half of all that produced electricity. The rest would have to be sold and transferred out on the grid or possibly be saved in a battery storage unit. What became obvious while calculating the profitability of a battery storage system was that, with today’s electricity pricing, to sell the surplus PV production out on the grid will always be the most economically profitable option. Economic profitability was a reoccurring theme, especially for the PV- and battery storage system. Most of the focus regarding the PV system was between the options of renting it or buying it. In the end it turned out not to be a very significant difference 5 between the two options, the most decisive aspect when choosing will most likely be the difference of overall comfortability between the two. Analysing the PV system became a larger part of this project than expected when another request was to figure out how big of a climate impact the system would have compared to if the same amount of electricity was used from Umeå Energis grid. This analysis came up with probably one of the most interesting results of this entire project. Because PV panels require a lot of energy to produce and a large proportion of all panels in the world are produced in countries with a high carbon footprint, it means that PV systems has one of the worst climate impacts of all renewable energy sources. According to Umeå Energi 100% of their electricity are produced from renewable sources where solar power is not one of them. Because of this it turned out that during the 25-year lifespan of the PV system it would have more than twice the climate impact rather than if the electricity came from the power grid. The Vidje couple also wanted to know more about newly developed technologies related to energy, among things like V2G, self-sustaining homes, hydrogen energy storage, direct current grids and electric vehicle charging, to be able to establish whether any of these would be possible to integrate with their home in the near future. V2G, Vehicle-to- Grid, is still very much under development and therefore are not available for any person to use. Self-sustainability is definitely possible with today’s standards, but the only method that seems to work well enough is hydrogen energy storage which is still not very well established on the market and therefore also very expensive. Readjusting your home to work with a direct current grid is an interesting trend that some knowledgeable people have been doing lately, but it seems to be just that, something only a person who is interested and knowledgeable in the area are capable to perform at this stage. There are now established technique for easily changing your home to be able to run on direct current. Because the Vidje couple are planning on getting an electric car it made them curious about what options there were to be able to charge it at home. The most critical question was if a charging box is a requirement or not. The answer is pretty simple, a charging box is technically not a requirement, but using a 230 V power outlet as standard is a very bad and sometimes even considered as dangerous. It is also a very inefficient method because regular outlets can only put out a relatively low power charge and therefore would mean unreasonably long charging times. An 11 kW charger box seems to be the best option right now be able to charge your electric car at home. Quick chargers above 22 kW to exist but are usually expensive and only lowers the charging time a little bit which for most households are quite unnecessary.

  • 446.
    Eklund, Victor
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utökad nytta av befintligt energilager2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The electrical grid is facing a modernization due to installations of intermittent energy production from wind and solar energy. Energy storage fulfills an important role in this modernization, with potential to store overproduced electricity and use it at a later time. By balancing electricity production and consumption with energy storage, it can provide the grid with stability, increased flexibility and reduce the grid load. An energy storage also makes it possible to keep down the dimensioning at exposed points in the grid, as in connections with high power fast charging stations.

    In the electrical grid of Umea Energy, there is a battery storage of 118 kWh, connected to a fast charging station for electric buses. The high power required by the charging station risked affecting nearby customers, therefore a solution with a battery storage was installed to reduce the impact. With this type of solution, a proportion of power can be retrieved from the grid and the battery storage simultaneously to the fast charging station, which contributes to the power output being smoothed out. However, solutions with battery storage are currently very expensive. To be able to justify an investment of this type of solutions, it is of interest to investigate whether it is possible to increase the utility of a battery storage in order to make the solution more profitable. The purpose of this paper is thus to examine how Umea Energy can increase the utility of a battery storage connected to a charging station and when such a solution may become an economic alternative.

    In this paper, simulation models have been developed in the software MATLAB to investigate whether the battery storage can be used to: 1) reduce power peaks in the neighboring residential area, where the results show that it is possible to reduce a small amount of power in the residential area but that the reduction is limited by how frequent the electric buses charges. 2) Move the load in the grid by letting the battery storage discharge during peak load hours and then recharge it at a later time. The result shows that it may be achievable for a certain time but it could affect the lifetime of the battery storage due to higher depth of discharge (DoD) and 3) Reduce the power during charging of the battery storage. The result indicates that the power can be reduced down to a quarter until affecting the charging schedule of the battery.

    The economic calculations that were carried out compared the profitability of installing a battery storage of 118 kWh to grid investments of 1) two transformers of size 800 kVA each or 2) new grid station incl. two 800 kVA transformers. The result show that there is no economic benefit for Umea Energy to install a battery storage of the investigated type of lithium titanate (LTO) or lithium iron phosphate (LFP) with prices based on 2016 but that it may become profitable with estimated prices from 2030.

    The conclusion that has been drawn from the simulations is that with regard of expanding the utility of a battery storage, there is only a small gain in using the battery storage to reduce power peaks. However, a lower maximum power required from the grid, can advantageously be achieved with a battery storage. In addition, the grid power can be reduced by moving the load during charging of the battery storage between the high peak hours or by reducing the power during the charging of the battery storage. With current battery prices, a battery storage is not considered a profitable investment, and therefore should only be installed to meet specific needs that would otherwise require expensive grid investments. However, the price trend for battery storage looks promising and with prices from forecasts of year 2030 it may become a competitive alternative.

  • 447.
    Ekman, Joakim
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energianalys av Romar fastigheter med metodutveckling för ökade incitament för   energieffektivisering hos hyresgäster2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Thesis is to work out an examplel of incentivesto motivate tenants to participate and invest in energy efficiency. The workincludes an energy audit of a building to be able to show what kind of savingsthat can be made and the investment costs involved. The property has all theenergy costs embedde in the price which means that tenants do not haveincentives to invest. The energy audit include night patrols to see what wasteenergy att night when there are no working, collection of data from Umeå Energy,an inventory of lighting and the acquisition of information on ventilation andthe compressor. Contact with different companies to get the approximate cost ofthe rationalizations. After the initial work was done the results were compiledand the result was a reduction in electricity consumtion by 354 MWh/year to 211MWh/year. The incentive in this case involves an adjustment of the rental formso that tenants self-pay energy costs and thus become more interested in beinginvolved in investments. An individual measurement of energy consumtion shouldbe as it is possible to assess how much each tenant is using. Investment costscan be split between tenants and landlords and bebefits of the investments canbe divided in the same way. Both parts benefits econonomically andenviromentally on cooperation.

  • 448. Ekstrand-Hammarström, Barbro
    et al.
    Magnusson, Roger
    Österlund, Camilla
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Pulmonary Medicine.
    Andersson, Britt M.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Bucht, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Pulmonary Medicine.
    Wingfors, Håkan
    Oxidative stress and cytokine expression in respiratory epithelial cells exposed to well-characterized aerosols from Kabul, Afghanistan2013In: Toxicology in Vitro, ISSN 0887-2333, E-ISSN 1879-3177, Vol. 27, no 2, p. 825-833Article in journal (Refereed)
    Abstract [en]

    In this study aerosol samples collected in an Asian mega-city (Kabul, Afghanistan) were compared to PM samples collected in a European location with traffic (Umea, Sweden) and a reference urban dust material (SRM 1649b). The toxicity of each sample towards normal human bronchial epithelial (NHBE) cells and a human bronchial epithelial cell line (BEAS-2B) was tested along with their ability to induce reactive oxygen species (ROS) formation and inflammatory responses. The extracts' morphology and elemental composition was studied by SEM-EDXRF, and filter samples were analyzed for metals and organic compounds. The PM from Kabul contained a larger fraction of fine particles, 19 times more polyaromatic hydrocarbons (PAH) and 37 times more oxygenated PAH (oxy-PAH) compared to samples from timed. The PM-samples from Kabul and the reference material (SRM 1649b) induced significantly stronger oxidative stress responses than the samples from Umea. Furthermore, samples collected in Kabul induced significantly higher secretion of the cytokines IL-6, IL-8 and GM-CSF while SRM1649b induced a cytokine pattern more similar to samples collected in Umea. Several properties of the particles could potentially explain these differences, including differences in their size distribution and contents of PAH and oxy-PAH, possibly in combination with their relative transition metal contents. 

  • 449.
    El Masry, Bosaina
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Ombyggnad av lägenheter i ett 1950-tals flerbostadshus till kontorsbyggnad2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The report aim to increase awareness of factors that have a major role when

    remodelling an apartment building from the 1950s to offices.

    The thesis can be used for future projects when remodelling apartments to offices.

    The report can provide ideas and inspirations on how this can be done in an

    effective way, ie . A way that does not require rebuilding the supporting structure,

    but only non bearing walls. The thesis also gives insight on the parts that will need

    to be supplemented from Boverket’s requirements in terms of accessibility,

    acoustic and fire requirements.

    The methods used in this thesis are literature studies, case study and sketch work.

    In the literature studies, the primary sources were Boverkets byggregler BBR, and

    Arbetsmiljöverkets föreskrift AFS 2009:2 but other literature were also used. The

    primary items were chosen from the literature studies and they were further

    analysed in the sketch work. It shows how the most common office solutions can

    be remodelled without tearing down load bearing walls and change the existing

    apartment building in an excessive degree. A case study of an apartment building

    is described.

  • 450.
    Elfving, Marcus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energieffektivisering genom behovsstyrning av inomhusklimat2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report deals with an energy efficiency project of a cinema in Umeå by controlling the indoor climate depending on the situation and by that way reduce energy consumption for heating and ventilation systems, yet managing to maintain a good indoor environment for occupants and that existing rules and laws are not broken. This energy efficiency was done by Schneider Electronic on one of Norrporten’s properties.

    Studies of various laws and sets of rules, including the “Boverkets Byggregler” (BBR) and “Socialstyrelsens allmänna råd”, was done to find out how to control the heating and ventilation systems so that the indoor climate can still keep the quality required.

    To know how to control the indoor climate in the theater information was needed about how the heating and ventilation systems were designed. This was investigated by means of field visits, interviews and literature studies. It appeared to be a system where the supply air was heated or cooled by a heating or cooling coil before it was sent out to the premises where the energy to the heat came from the district heating while the coolness was driven by electricity. Some radiators were in the hallways and beneath the windows in the foyer and in the theaters there were air heaters that could be used if necessary.

    The energy efficiency project was that the heating and ventilation systems would not work as hard, but most important they would be running fewer hours during the day and night. This would be solved by installation of DUCs (Data under centrals) and various different sensors, which together would determine which heating and ventilation requirements needed at a particular time and control the systems based on them.

    During the project a number of shortcomings and side effects were revealed and needed to be addressed. These shortcomings were both those that were due to the project and those that had not been discovered by Norrporten earlier, such as whishing noise, poor efficiency of heat recovery, bad odors and high air velocities.

    The results of this project was beyond the expectations when the estimated savings were a little less than 60 kWh/m2 while the actual savings was just over 100 kWh/m2. The money that was saved the first year were nearly 75% larger than expected from the estimated figure of about 160 000 SEK to the real saving of about 280 000 SEK.

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