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  • 101.
    Andersson, Simon
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstruktion av reaktionsmätare: För mätning av mental belastning hos traktorförare2015Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
  • 102.
    Andersson, Staffan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utvärdering av energieffektiva armaturer2015Report (Other academic)
    Abstract [sv]

    Rapporten redovisar en genomförd uppföljning av den erhållna minskningen av varm- respektive kallvattenanvändningen genom installation av energieffektiva armaturer. Utvärderingen baseras på 23 månaders mätningar av den individuella vattenanvändningen i sjuttiosju lägenheter (21 test-samt 56 referenslägenheter). Testlägenheterna utrustades först med en tidigare generations vattenarmaturer, FM Mattsson serie 9000, vilka senare ersattes med den senaste generationens armaturer FM Mattson serie 9000E. I fem av dessa lägenheter har dessutom komplementerande mätningar gjorts vid de olika tappställena, WC undantagen. Användningen av varm- och kallvattenanvändningen i varje lägenhet har loggats med en tidsupplösning om 10 minuter. För att undvika påverkan av boendes frånvaro från lägenheterna har uppföljningen baserats på den genomsnittliga dygnsanvändningen av vatten för de tider de boende har nyttjat lägenheten. Lägenheter där byte av hyresgäster har skett under utvärderingsperioden har lämnats utanför utvärderingen. De erhållna resultaten visar på en besparing om cirka 30% avseende varmvattenanvändningen samt 15% avseende kallvatten jämfört med referensgruppen. Den erhållna uppskattningen är också konsistent med en teoretisk uppskattning av besparingen baserad på den mätta förändringen av kvoten mellan varmvatten- och kallvattenanvändningen i testlägenheterna.

  • 103.
    Andersson, Staffan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Östin, Ronny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Predictions of energy demand in buildings using neural network techniques on performance data1996In: Proceedings of the 4th fourth symposium on building physics in the nordic countries, 1996, p. 51-58Conference paper (Refereed)
  • 104.
    Andersson, Staffan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Sjögren, Jan-Ulric
    Östin, Ronny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Building performance based on measured data2011In: World Renewable Energy Congress – Sweden, 8–13 May, 2011, Linköping, Sweden: Energy End-Use Efficiency Issues / [ed] Moshfegh, Bahram, Linköping: Linköping University Electronic Press , 2011, p. 899-906Conference paper (Refereed)
    Abstract [en]

    With increasing liability for builders, the need for evaluation methods that focuses on the building’s performance and thus excludes the impact from residents’ behavior increases. This is not only of interest for new buildings but also when retrofitting existing buildings in order to reduce energy end-use.

    The investigation in this paper is based on extensive measurements on two fairly representative type of buildings, a single family building in Ekerö, Stockholm built 2000 and two apartment buildings in Umeå (1964) in order to extract key energy performance parameters such as the building’s heat loss coefficient, heat transfer via the ground and heat gained from the sun and used electricity.

    With access to pre-processed daily data from a 2-month periods, located close to the winter solstice, a robust estimate of the heat loss coefficient was obtained based on a regression analysis. For the single family building the variation was within 1% and for the two heavier apartment buildings an average variation of 2%, with a maximum of 4%, between different analyzed periods close to the winter solstice.

    The gained heating from the used electricity in terms of a gain factor could not be unambiguously extracted and therefore could only a range for the heat transfer via ground be estimated. The estimated range for the transfer via ground for the two apartment buildings were in very good agreement with those calculated according to EN ISO 13 370 and corresponded to almost 10% of the heating demand at the design temperature. For the single family building with an insulated slab and parts of the walls below ground level, the calculations gave slightly higher transfer than what was obtained from the regression analysis. For the estimated gained solar radiation no comparison has been possible to make, but the estimated gain exhibited an expected correlation with the global solar radiation data that was available for the two apartment buildings.

  • 105.
    Andersson, Staffan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Sjögren, Jan-Ulric
    Östin, Ronny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Prestanda- och betendeuppföljning av byggnaders energianvändning: etapp12010Report (Other academic)
  • 106.
    Andersson, Stefan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Inventering av småskalig vattenkraft: En undersökning av gamla vattenkraftsdammars potential i Västerbotten och Västernorrland2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 107.
    Andersson, Thobias
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Metodutveckling för Testning av Skivstänger2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Baltic Fitness sells and produces functional training equipment. The company wants to develop and create its own barbell brand. In order for this to be possible, it is necessary to provide the basis for the production of barbells and the barbells need to pass different tests to ensure that the quality is at the level desired.

    During the work, a survey of different barbell tests has been compiled that ensures the barbell meets the standard. Around the selected tests, a thorough study has been made to find out how and when the tests are to be performed, what safety is required, what components are required to perform the test and the result that must be achieved in order for the barbells to be approved in the test. A manual has been compiled to describe the approaches to the tests. The manual describes the importance of the tests and a price estimate for the necessary components has been compiled.

  • 108.
    Andersson, Tomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Optimering av balkonglösning2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This dissertation describes the theory behind a specific solution for balcony attachment for concrete constructions designed by Prefabmästarna. The purpose is to get a deeper understanding of design according to Eurocode and EKS (Swedish application of eurocode) and to optimize the current solution for balcony attachment in view of reduced material usage. The design is based on a prefabricated balcony slab is fasten to a T-section whose flanges are molded in a prefabricated DFS-slab. Two tie-rods is threaded into the balcony slab and fasten to the T-section with a washer. After mounting of the balcony slab the DFS slab is molded on which stabilizes the T-section from instabilites. The results show that the structure is largely optimized but that there are room for improvements in specific places. For balconies with a length of 2.0 meters the T-section can be reduced with 10 kg of steel, which corresponds to more than 50 % of the T-section weight compared with the reference solution. Also at the 2.5 meter balconies the T-section can be reduced with 7 kg of steel, which corresponds to a 38 % reduction in material use compared with the reference solution. A common standard for the T-section is possible for balconies with a length of 2.0 and 2.5 meters.

  • 109.
    Andreas, Domeij
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energieffektivisering av en gammal kulturmärkt prästgård2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Reducing and improving the use of energy is something that is relevant in the current situation for both economic and environmental aspects. Energy goals have been set up to achieve a better and more efficient use of energy. This leads to buildings constructed as efficient as possible but it also involves existing buildings. This report investigates an old heritage rectory from the 1700’s that, with its high use of energy, will be analyzed and then simulated with a few measurements in the energy calculation program VIP Energy.

    The information about the rectory is limited. Many assumptions regarding the building’s construction and the occupants’ behavior were applied since documentation has been missing and since the building is currently empty. Svenska kyrkan is currently rebuilding the rectory since they intend to conduct business there in the future. A model was created in VIP with the goal to simulate the rectory when there still was activity in the building. The model were then simulated various measures that were additional insulation, renovation of windows and an installation of a FTX-system. The culture label has made measures that affect the façade, such as external insulation or replacing windows, disregarded.

    The results from the model showed that with all the measures together it is possible to reduce the specific use of energy of the rectory from 252 kWh/m

    2 to 111 kWh/m2 and thereby live up to the guidelines posted by The National Board of housing, Building and planning. Certain factors have deliberately been ignored such as moisture, due to time restrictions. The same thing applies to the economic part except for the ventilation where a lifecycle cost between a rotating heat exchanger and a plate heat exchanger has been compared to replace the existing exhaust system. The reason is that the ventilation is the most feasible solution for adaption to future use. LCC analysis showed a benefit to the rotary heat exchanger favor with a price difference for about 70 000 SEK towards the existing system, without installation costs or future reparations.

  • 110.
    Andreasson, Albin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstant eller behovsstyrd ventilation i grundskolan: En jämförelse med hjälp av LCC-analyser2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Demand controlled ventilation is recognized as an option to constant air volume (CAV) ventilation. Capable of reducing the cost of energy usage, but having higher initial costs. This thesis investigates both these factors in order to see what gives the lowest LCC (life cycle cost).Using the case of a 1000 m2 primary school in Stockholm, Sweden, four different ventilation systems were analyzed: constant air volume (CAV) ventilation, CO2 controlled ventilation, CO2 and temperature controlled ventilation as well as occupancy controlled ventilation.All of the systems were constructed in the AutoCAD software, using the add-on MagiCAD. This made it possible to acquire detailed bills of materials that were exported to the accounting software Sektionsdata, which was used to calculate the initial costs of the systems down on a component level.The energy calculation software IDA ICE was used to perform simulations on both energy usage and indoor climate. Each system was simulated with three different sizes of occupancy.LCC was calculated for each system and occupancy using the net present value method, where CAV got the lowest with a wide margin. CO2 controlled ventilation got the second lowest LCC followed by CO2 and temperature controlled ventilation. Occupancy controlled ventilation got the highest LCC with a wide margin. This order did not depend on the size of the occupancy, but the LCC of the carbon dioxide controlled systems got smaller in comparison with the other systems when the occupancy was reduced.

  • 111.
    Andreasson, Simon
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Datainsamling röntgen2011Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 112.
    Anette, Nyström
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Undersökning av smarta energilösningar för en planerad livsmedelsbutik2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    På uppdrag av Hifab AB har detta examensarbete utförts under vårterminen 2015. En ny livsmedelsbutik ska etableras i Umeå, där Hifab AB har anlitats som generalkonsult av Coop Nord. I dagsläget finns endast ett utkast på hur byggnaden ska se ut eftersom byggnationen av butiken beräknas starta våren 2016. Detta innebär att det finns stora möjligheter att undersöka smarta energilösningar som kan appliceras på den framtida butiken. För att erhålla energistatistik att utgå från användes en Coop-butik i Kramfors som invigdes våren 2012 som referensbutik i detta projekt.

    Syftet med detta arbete var att undersöka olika energialternativ och energieffektiviserande byggtekniska lösningar för den planerade butiken. Detta för att den planerade Coop-butiken, tillsammans med andra framtida butiker, ska kunna byggas energieffektiv redan från början och för att driftkostnaden för butiken ska bli så låga som möjligt samtidigt som påverkan på miljön blir minimal. Detta projekt ska vara en vägledning i val av energisystem och byggtekniska lösningar för den aktuella Coop-butiken och även vid projektering av framtida livsmedelsbutiker i Sverige, framförallt i norra delen av landet.

    Projektet har innehållit två olika delar och ett flertal mål. Det första delmålet var att undersöka vilket av alternativen fjärrvärme eller bergvärme som är det mest ekonomiskt lönsamma för den nya butiken. Nästa delmål var att undersöka möjligheten och kostnaden för att installera solceller på den nya butiken. Målet var även att undersöka om det fanns alternativa sätt att tillgodose kylbehovet på jämfört med de kompressorkylmaskiner som finns i referensbutiken. I den andra delen av projektet var målet att bygga upp en modell av referensbutiken i ett energiberäkningsprogram och att simulera energieffektiviserande lösningar på denna. Detta för att undersöka hur mycket energibesparingar som kunde erhållas, framförallt i minskat uppvärmningsbehov per år.

    De metoder som användes för utförandet av detta arbete var studiebesök, intervjuer, kontakt med företag, litteratursökning och datorsimuleringar. Inledningsvis utfördes ett studiebesök på referensbutiken för att få en överblick över dess utformning och uppbyggnad. För undersökningen av fjärrvärme, bergvärme och solceller upprättades kontakt med olika leverantörer medan undersökningen av alternativa kylmetoder utfördes som en litteraturstudie. För den andra delen av projektet valdes IDA Indoor Climate and Energy (IDA ICE) att användas som energiberäkningsprogram. Referensbutiken modellerades i programmet och fick sedan fungera som grundfall på vilken ett antal, utvalda energieffektiviserande lösningar testades.

    De viktigaste slutsatserna i detta projekt är att när värmesystem ska väljas för den nya butiken så är fjärrvärme ett mer lönsamt alternativ när valet står mellan fjärrvärme och bergvärme. Slutsatsen för den del i projektet där solceller undersöktes är att det är en lönsam investering att installera solceller på den nya butiken utifrån de beräkningar som har erhållits från två leverantörer. Det bästa alternativet var en tunnfilmssolcell som gav en återbetalningstid på cirka sju år och en investeringskostnad på cirka 1,5 miljon kronor om statsbidraget erhålls. Av det totala elbehovet skulle då cirka 20 % täckas av produktionen från solcellspanelerna. Slutsatserna som kan göras när de energieffektiviserande lösningarna testades var att de två som gav störst energibesparing var behovsstyrning av ventilationsflödet och minskad belysningseffekt. Dessa två energieffektiviserande lösningar rekommenderas att undersökas närmare för att utreda möjligheten att implementera i den nya butiken.

  • 113.
    Angelica, Nordin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    En studie om typografins betydelse i analogt format2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract (EN)

    This paper is the final part of the Media Producer Program at Umeå University, including a supplementary year. This essay is a Bachelor thesis in media technology.

    The purpose of this was to deepen my knowledge and extend my skills in graphic design, especially for printing. The goal was to find an answer to the question "what is the significance of typography in the analog format?". Another purpose was to test the hypothesis "it is harder to read text written in a different color than black on a white/light background".

    This thesis are for those who are interested in typography and its importance. The thesis also refer to the history about typography, the structure and basic rules. It also presents a survey of its significance in the analog format. Not a statistical survey, but an empirical study that captures a bunch of opinions and values ​​about the use of typography.

    The results of the survey are presented with texts and tables, and it shows a disagreement to what the literature says. The result shows that people read text written with sans-serifs rather than text written with serifs. It also shows that people doesn’t thinks it’s harder to read text written with other colors than black on light backgrounds.

     

    The result of the side project appears with texts and pictures, so you  can get an overview about the layout and how the results of the study, and the theory, are implicated.

    In the essay I have also looked at scientific articles. You can read about that in the discussion section, where you also find suggestions to further studies and research in typography, as well as thoughts on the work in its entirety.

  • 114.
    Apelqvist, Bo-Isak
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energikartläggning av LKAB:s underjordsgruva i Malmberget2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The LKAB mine in Malmberget used 258 GWh of energy in 2011, broken down by different types of energy where the share is shown as a percentage in the brackets below. • Electricity 183 GWh (71%) • Diesel 4897m

    3 or 49 GWh (19%) • Fuel oil 2378 m3 or 26 GWh (10%) • Energy consumption per tonnes of production was 15.91 kWh/ton The total quantity of crude ore mined in 2011 amounted to 16 193 tonnes and energy consumption was 257 609 MWh. Corresponding figures for 2005 were 14 035 tonnes of crude ore and energy use was 219 392 MWh, which gives a figure for energy consumption per tonne of 15.63 kWh/ton. Production has increased by 15.4% and energy consumption by 17.4% from 2005 to 2011. The increase is mostly because the mining occurs at greater depths and more energy is required to transport the ore to ground level. The energy audit has been carried out with respect to the mine in Malmberget and a comparison of energy use is made with information from a previous compilation from year 2007 (base year 2005). Year 2011 is chosen as the base year for this energy audit and it is then compared to the 2005 values to get a picture of how energy use has changed since then. The survey is updated with the new main level M1250 which began to be operational during the first half of 2011. The proposed efficiency measures in chapter 5 are discussed and anchored within the company. A sectioning of responsibility for the different areas of action is made with PS, PE / PI, TP and EP included as head responsible. The proposed measures with the greatest potential savings have been identified for each area of responsibility and should be prioritized. Priority actions are ventilation heat recovery, measurement and monitoring, and interventions for behavior change.

  • 115.
    Appelgren, Ester
    et al.
    Södertörns högskola.
    Leckner, Sara
    Malmö högskola.
    Mejtoft, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    The media consumers' conscious and unconscious choices: a key to understanding the news media consumption of tomorrow2014In: Communication électronique, cultures et identités: actes du colloque international organisé au Havre les 11, 12 et 13 juin 2014, Editions Klog , 2014, p. 521-528Conference paper (Refereed)
    Abstract [en]

    The digital society of today is dramatically different than that of a decade ago. During the past decades computers have gone from being clearly visible and at the center of attention to becoming an integrated and omnipresent part of our everyday lives. Today, individuals are catching up on a reality where homes, workplaces and society to a large extent consist of microprocessors that collect, analyze and present information. With regards to news and information sharing, it may seem that the users, thanks to greater ability to choose content, hold the upper hand in this process. However, since these data are constantly collected and analyzed for various purposes by companies, for example in the media industry, the users’ choices may not be as unconditional as they may think they are.Using the Swedish media market as an example, this exploratory paper discusses the interdependency between people’s choices and the market-driven choices made by the media industry in relation to news, and the impact these choices may have on media consumption and the media market.

  • 116.
    Appelgren, Ester
    et al.
    Södertörns högskola.
    Sara, Leckner
    Malmö högskola.
    Mejtoft, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Mediekonsumentens medvetna och omedvetna val: en nyckel till morgondagens mediekonsumtion2014In: Medie-Sverige: statistik och analys. 2014 / [ed] Ulla Carlsson & Ulrika Facht, Göteborg: Nordicom, 2014, p. 29-37Chapter in book (Other (popular science, discussion, etc.))
  • 117.
    Aranovskiy, Stanislav
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Adaptive Attenuation of Disturbance Formed as a Sum of Sinusoidal Signals Applied to a Benchmark Problem2013In: 2013 EUROPEAN CONTROL CONFERENCE (ECC), NEW YORK: IEEE , 2013, p. 2879-2884Conference paper (Other academic)
    Abstract [en]

    The problem of adaptive attenuation of a disturbance formed as a finite sum of unknown sinusoidal signals is solved for a discrete-time plant with unstable zeros. It is assumed that a reliable model of the plant is known and the system is internally stable. We propose to construct a control signal as a linear combination of outputs of carefully chosen filters. The coefficients of the combination are tuned via an on-line identification based on the plant model. However, our approach avoids constructing an inverse of the plant model. The technique is applied to a case study on a challenging benchmark example in the field of active vibration control. Attenuation of a disturbance formed as a sum of up to three unknown/time-varying sinusoidal signals is demonstrated via simulation and experimental studies.

  • 118.
    Aranovskiy, Stanislav
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Modeling and identification of spool dynamics in an industrial electro-hydraulic valve2013In: Mediterr. Conf. Control Autom., MED - Conf. Proc., 2013, p. 82-87Conference paper (Refereed)
    Abstract [en]

    Approximate models of spool dynamics are proposed to deal with dynamic delays observed for an industrial electro-hydraulic valve. The suggested model consists of a linear block and two static nonlinearities. A method for identification of parameters is suggested that allows to deal with a case when only pressure in a hydraulic cylinder is measured but not the displacement of the spool. The approach is verified experimentally.

  • 119.
    Aranovskiy, Stanislav
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. The Department of Control Systems and Informatics, National Research University of Information Technologies, Mechanics and Optics, Saint-Petersburg, Russia.
    Freidovich, Leonid
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Adaptive compensation of disturbances formed as sums of sinusoidal signals with application to an active vibration control benchmark2013In: European Journal of Control, ISSN 0947-3580, E-ISSN 1435-5671, Vol. 19, no 4, p. 253-265Article in journal (Refereed)
    Abstract [en]

    An intuitive solution for the problem of adaptive attenuation of a disturbance formed as a finite sum of unknown sinusoidal signals is proposed for an internally stable discrete-time plant. The compensator is formed as a weighted sum of stable filters. An identification-based procedure for adaptive tuning of the coefficients is proposed for the case of unknown disturbance. We also propose a time-invariant compensator that provides perfect attenuation of a disturbance for the case when a model identification error is sufficiently small and disturbance frequencies are known. The technique is applied to a case study on a challenging benchmark example in the field of active vibration control. Attenuation of a disturbance formed as a sum of up to three sinusoidal signals with unknown/time-varying frequencies is demonstrated via simulation and experimental studies. (C) 2013 European Control Association. Published by Elsevier Ltd. All rights reserved.

  • 120.
    Aranovskiy, Stanislav
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Department of Control Systems and Informatics, ITMO University.
    Freidovich, Leonid
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Nikiforova, LV
    Department of Control Systems and Informatics, ITMO University.
    Losenkov, AA
    Department of Control Systems and Informatics, ITMO University.
    МОДЕЛИРОВАНИЕ И ИДЕНТИФИКАЦИЯДИНАМИКИ ЗОЛОТНИКОВОГО ГИДРОРАСПРЕДЕЛИТЕЛЯ: ЧАСТЬ I. МОДЕЛИРОВАНИЕ / ЧАСТЬ II. ИДЕНТИФИКАЦИЯ2013In: Scientific and Technical Journal «Priborostroenie», ISSN 0021-3454, Vol. 56, no 4, p. 253-265Article in journal (Refereed)
    Abstract [en]

    MODELING AND IDENTIFICATION OF DYNAMICS OF A HYDRAULIC ACTUATOR WITH A SPOOL VALVE. PART I. MODELING

    Approaches to the problem of modeling of hydraulic actuator are considered. A model for the spool dynamics consisting of a linear block and two static nonlinear subsystems is presented.

    MODELING AND IDENTIFICATION OF DYNAMICS OF A HYDRAULIC ACTUATOR WITH A SPOOL VALVE. PART II: IDENTIFICATION

    A method for identification of dynamic model parameters is suggested for the case when only pressures in the hydraulic cylinders but not the valve displacements are measured. The approach is verified by presented results of experiments.

  • 121.
    Aranovskiy, Stanislav
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Department of Control Systems and Informatics, ITMO University, Saint-Petersburg, Russia.
    Losenkov, Andrei
    Department of Control Systems and Informatics, ITMO University, Saint-Petersburg, Russia.
    Vazquez, Carlos
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Position control of an industrial hydraulic system with a pressure compensator2014In: Proceedings of the 2014 22nd Mediterranean Conference of Control and Automation (MED 2014), Institute of Electrical and Electronics Engineers (IEEE), 2014, p. 1329-1334Conference paper (Refereed)
    Abstract [en]

    A problem of position control of a forestry crane is studied. Several features of industrial hydraulic systems are pointed out, namely a nonlinearity of a valve and a pressure compensator. A novel model of a hydraulic system with the pressure compensator is presented and analyzed, a static nonlinearity inversion and a velocity feedforward control term are introduced. Real-time experiments with controllers which use only position measurements illustrate utility of these terms.

  • 122. Aranovskiy, Stanislav
    et al.
    Vazquez, Carlos
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Control of a single-link mobile hydraulic actuator with a pressure compensator2014In: 2014 IEEE Conference on Control Applications (CCA), 2014, p. 216-221Conference paper (Refereed)
    Abstract [en]

    A problem of position control of a single-link hydraulic drive, including model uncertainties and disturbances, is studied. Main properties of mobile hydraulic systems are taking into account, namely a nonlinearity of a valve and a pressure compensator. A discontinuous control law coupled with a static nonlinearity inversion and a feed-forward term of velocity is proposed. Besides, a novel model with pressure compensator is presented and the closed-loop stability analysis is provided. Results of experiments carried out on a forestry crane confirm the efficacy of the proposed approach.

  • 123.
    Arencibia, Ariel
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Undersökning av fasadskivor2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this report is to present some of the market's façade panels and to do a survey of Masonite façade panels and compare. Therefore I have looked closer on potential competitors and studied their assembly method and properties. I will also propose suggestions on installing Masonite panels and improvements to the current carrying system. The carrying system for façade panels in general.

     

    Various key people in various areas of the construction industry have been interviewed. People with a wide knowledge of theory and with real work experience have been my main focuses too implement this survey. I have also collected data from the façade panel system’s properties.

     

    There are benefits with Masonites façade panel but I also found that there is a possibility to make changes to improve their properties. The improvements are only theory and not tested in practice, but it could be a good start for improvement on the façade constructions. The results of my research and my proposals are explained in more details later on in this essay.

  • 124.
    Arljung, Jerry
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Byggfysik vid prefabricerade träväggar2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The work is about prefabricated houses with wooden frames. The company that I am doing thesis examination work in units Attacus Jämtlandshus Ltd whose business is to manufacture timber frames to the building industry. This work demonstrates Jämtlandshus work process and the methods used to reach to the final product. These methods are documented in detail for possible identification activities likely to affect final product quality negatively. Also reported a large number of calculations and other values that indicate what the quality of the final product is given to heat, moisture and air tightness. The report also shows how the industries that are working with production systems use them to be as effective as they can and as competitive as possible. In reaching the above, the author used a lot from their previous experience as an employee of this company, this is above all the documentation of work processes. To perform the calculations presented, the author has made use of prior knowledge from the course, building physics, and some contact with outside professionals. The work aims to, if it is possible, to identify any weak points in production and to assess how good quality the final product is given to tightness. Both the author and Jämtlandshus think it is strange that this building technique is not bigger and more "recognized" in the market than is currently the case. By reading this report, the reader can get up their interest in prefabrication to a greater extent and start weighing the advantages and disadvantages compared with site construction. This work demonstrates the quality of these houses, and some advantages of making wooden houses by prefabrication. The author's hope through this work is that more people will open their eyes to this building techniques and that, generally, people begin to talk about these types of houses.

  • 125.
    Arnlund, Caroline
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utveckling av sensor för mätning av hjärtaktivitet2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Motion analysis is a necessary tool when it comes to evaluation, monitoring and diagnosis of all the diseases that affect the human musculoskeletal system. There are only a few clinical walking laboratories in Sweden, where the patients can receive a more detailed and objective evaluation of their walking patterns. The problem with these laboratories is that they are relatively expensive and resource-demanding.

    The department of research and development at NUS has initiated a research project where AnyMo, a mobile system for measuring of moving patterns, was produced. The aim of this thesis was to further develop the existing system to simultaneously measure the electrical activity of the heart (ECG).

    The parts that were constructed during this project was an ECG sensor and a Master Unit, coupled to an existing motion sensor (part of the AnyMo system). The information that was collected from these sensors was stored locally in a memory on the system’s Master Unit.

    The finished product was tested and evaluated on a stationary bike at different pace and heart rate.

  • 126.
    Arnqvist Eriksson, Petter
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Greppmekanism för avgasutsug på moderna bilar2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report has been carried out in cooperation with Fumex AB, which operates in Skellefteå, Sweden and develops environmental products. Auto repair shops and vehicle inspection companies today use exhaust extraction when working with vehicles to maintain a good working environment. The exhaust gas pipe design and location on the cars have changed over time, and today, most extraction nozzles have problems being attached to the exhaust pipes on modern cars.

    The aim of the project was to develop and produce a gripping mechanism that can attach a nozzle to almost all modern cars, and also develop a design proposal of the nozzle. A requirement specification was created and formed the basis for the development process.

    Systematic methods were used for concept generation and screening of ideas because design problems are often difficult to solve solely on intuition. A brainstorming session was held for the generation of ideas and the decisions was taken by means of elimination- and decision matrixes together with gut feeling. In the decision matrix the generated concepts were benchmark tested against the market-leading product.

    The gripping mechanism and the nozzle was designed in PTC Creo which is a CAD software, and the prototype of the gripping mechanism was manufactured by Nordramp AB in Skellefteå. The result is a product with relatively low complexity and which has a total production cost of 453SEK which is about 54 % of the competing company's market leading product. The product grasps exhaust tailpipes with lateral dimensions 30-95mm with about the same force regardless of the cross-sectional dimensions and shape. The weight of the product including the nozzle is calculated to be 2.2kg which is the same as the aforementioned market leading product.

    It is further proposed that the prototype of the nozzle is produced and the entire product is evaluated so that knowledge is obtained if it meets the given requirements of the requirement 

  • 127.
    Arnqvist, Kristoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Analys av jordning för kraftproducerande anläggningar2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The safety regulations for grounding have been made stricter during later years; there are new rules and laws as well as recommendations and methods for how modern power producing facilities are to be grounded in a correct and safe manner. The purpose of this thesis has partly been to gather knowledge on these regulations as well as conducting an analysis of the grounding carried out at Vattenfalls hydro power plant G5 in Stornorrfors.

    A study of literature has been conducted and a site study was conducted with testing of earthing sites, measurement of currents and inspection of the hydro power plant G5 from a grounding perspective.

    Measurements show that the G5 power plant is a thorough and exemplary facility with very good qualities for handling earth faults., transients and preventing stray currents. The facility has a rigorous equipotential bonding where cableladders, stairs, pipes and exposed metal surfaces are all equipotentially bonded. The facility holds a good connection to earth at earthing sites when measurements revealed all earth sites having an earth resistance value less than 1 Ω. The earth sites and earth system showed only slight increases in impedance when measurements with high-frequency currents were carried out and the facility is deemed to be able to handle high-frequency currents in a satisfying manner.

    Through measurements of earth currents it was revealed that currents run in the earth wires, most likely due to the strong magnetic field generated by the generator, and it is unclear how these currents affect the earthing system and equipment over longer periods of time when some currents exceeded 10 A.

    No surge arresters were found by the facility or the transformer next to it, some were found however where the cable is replaced by hanging wires after the emergency power building. An inventory of surge arresters is recommended. The lighting protection system found on the roof of the facility should be repaired and possibly adressed in order to withstand damage caused by heavy snowfall. The facility is very exposed to the public and access to the facility should be restricted through fences and gates.

    Grounding a power producing facility today incorporates many different areas within electrical technology and therefore also holds a broad variation in how a safe installation is classified and examined. Making a facility "completely safe" is not obvious there will always be a need for compromises and considerations as no situation is similar to the next one in real life.

  • 128.
    Aronsson, Anton
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstruktion av forcerat komponentprov: Metod för utförande av utmattningsprov på delkomponent i skördaraggregat.2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report comprises a construction of an fatigue testing equipment for a certain component at Komatsu Forest in Umeå. Testing components fatigue limit can act as compliment to the theoretical calculations. Fatigue testing equipment facilitates redesign by components because it gives fast response on whether changes was good or bad.The component this report deals with is a shaft mounted in a c144 harvester head. The axle is analysed regarding cracks, failure and through calculations with finite element method. The analysis indicates that the axle is exposed to bending forces that ultimately leads to its failure. The analysis and practical restrictions becomes the base for the design of the equipment. The equipment is designed to re-create the axles fatigue breaking through bending. Different designs regarding the equipment is discussed and also their advantages and disadvantages.The report result in complete manufacturing documents with drawings for all components and exploded views of the equipment. How the fatigue tests are done, measured, monitored and evaluated is also included in the report.

  • 129.
    Aronsson, Johan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    NEXT-analys av kablage för Ethernetkommunikation i påfrestande miljöer2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 130.
    Artursson, Robin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Mätsystem för gripkraft2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Normaltryckshydrocefalus (NPH) är en sjukdom som påverkar dynamiken i cerebrospinalvätskesystemet och leder till förstorade ventriklar samt problem med gångrubbningar, urininkontinens och i vissa fall demens. I dagsläget kan det vara svårt att diagnosticera NPH-patienter då de första symptomen på sjukdomen är tendens till gångrubbningar och detta är svårt att använda som underlag då det är svårt att mäta i daglig klinik.

    I ett försök att komplettera undersökningen av NPH-patienter utvecklade jag därför på avdelningen för Medicinsk Teknik- FoU vid Norrlands Universitetssjukhus en mätutrustning med syftet att undersöka om hand- och greppkraft kan användas som underlag vid diagnos då det är enklare att mäta än att uppskatta gångrubbningar.

    Det konstruerades ett mätsystem med en styrenhet, datalogger, kraftgivare och accelerometer för att mäta kraft och acceleration i 3 axlar och spara ner denna data på ett SD-kort.

    Det färdiga mätsystemet är testat på fyra olika testpersoner och en analys är gjord på mätresultaten. I jämförelse med resultaten från en tidigare studie som bygger på mätningar med en liknande utrustning (1), uppnås goda resultat som indikerar att det färdiga mätsystemet kommer att lämpa sig väl för mätningar i den kliniska vardagen.

  • 131.
    Arén, Axel
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    The effect of resident related input data on the specific energy use2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 132.
    Asp, Simon
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Reducing Food Waste with a Sustainable Lunch Concept: A Service Design Project2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Environmental problems such as pollution and overconsumption is something that is mentioned often in the news as this thesis is written. Food waste is a problem that causes valuable resources to be lost, as on average one third of all food globally is being wasted. The food chain is complicated, from the farm to the table, and innovations in all parts of the chain could help reduce the waste. We have aimed our scope to the end of the chain, when food is made at a restaurants to be served to customers. Figures say that about 23% of food in the restaurant business in Sweden is being wasted. To try to solve this problem, we have turned to service design and the methodologies presented there, to find a potential solution that could help reduce food waste.

    An extensive service design process was made with many interviews with restaurants to find where a solution could be made. The whole design process is presented in the report, and the final concept resolves around a sustainable lunch dish that can be made out of ingredients that would otherwise be thrown out. The dish would be sold at lunch restaurants for a reduced price since it is cheap to make, and would make more people act sustainable. A concept test was made to evaluate the the sustainable dish concept with the help from the public. The main question was:

    Is this concept something that could be adopted by people who buy lunch on a regular basis in Sweden?

    The concept test resulted in 165 respondents that were asked what they would choose to eat from a given menu. 32% chose the sustainable dish, and although biases were believed to have played a role in the decision, the concept was deemed successful. A website was then designed, aimed towards restaurants that wanted to adopt the concept and to get started in an easy way.

  • 133. Aspholm, Marina
    et al.
    Kalia, Awdhesh
    Ruhl, Stefan
    Schedin, Staffan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Arnqvist, Anna
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Lindén, Sara
    Sjöström, Rolf
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Gerhard, Markus
    Semino-Mora, Cristina
    Dubois, Andre
    Unemo, Magnus
    Danielsson, Dan
    Teneberg, Susann
    Lee, Woo-Kon
    Berg, Douglas E
    Borén, Thomas
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Helicobacter pylori adhesion to carbohydrates.2006In: Methods in enzymology, ISSN 0076-6879, Vol. 417, p. 293-339Article in journal (Refereed)
  • 134.
    Aspholm, Mattias
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utredning av frekvensomriktaresinverkan på sin närmiljö2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Fokus läggs mer och mer på hur olinjära laster påverkar spänningsgodheten pånätet. Ledorden är att ”du skall icke sabotera din grannes spänningskvalitet!”.Detta gillar nätbolagen och allmänheten men i vissa delar av nätet är det inte lika nödvändigt att hålla så hårt på elkvaliteten. Industrier har ofta anläggningar som är avskilda öar från det elektriska fastlandet. Därför gjordes mätningar på befintlig anläggning med stor del frekvensomriktardrift för att kunna jämföra med simuleringar från dimensioneringsprogram och slutligen utifrån resultatet dra slutsatser om hur man ska utveckla tankesättet vid dimensionering av frekvensomriktare för att göra den mer kostnadseffektiv.

  • 135.
    Asplund, Jesper
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Processkartläggning och metodstudier på Ålö AB2014Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
  • 136.
    Asplund, Jesper
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Processkartläggning och metodstudier på Ålö AB2014Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport är resultatet av examensarbete för högskoleingenjörsexamen i maskinteknik förlagt vid Ålö AB.

    Ålö är en världsledande tillverkare av frontlastare, redskap och fundament för jordbrukstraktorer. Vid produktionsanläggningen i Brännland utanför Umeå tillverkas en mängd olika varianter av lastare.

    Projektet omfattar processkartläggning av förbehandlingsprocessen som en lastare genomgår innan den målas. Vid en internrevision uppdagades brister inom processorientering vid förbehandlingen. Processorientering är en av Ålös bärande principer och viktigt för att säkerställa att arbetet sker enligt korrekta rutiner, instruktioner och system. Detta säkerställs delvis genom att Ålö beskriver sin verksamhet med processkartor, nedbrytbara i flera nivåer.

    Projektets mål var att skapa en processkarta över arbetsmoment och rutiner vid förbehandlingen. Syftet var att på sikt hjälpa Ålö standardisera sina arbetssätt och förbättra sitt processorienterade arbete.

    Information om processen inhämtades genom workshops, praktik och litteraturstudier. Arbetet resulterade i en processkarta över förbehandlingsprocessen samt en tillhörande handbok för att ge en sammanfattande beskrivning av processen. Rapporten avhandlar även grundläggande begrepp och metoder relaterade till processkartläggning.

    Resultatet visar att processen överlag har en hög mognadsgrad, där det huvudsakliga problemet är bristande dokumentation. En brist som detta projekt delvis avhjälper, men som kräver fortsatt arbete med processkartläggning och arbetsinstruktioner.

  • 137.
    Asplund, Jonas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Maskin för simulering av tuggprocessen: - för utveckling av implantat inom protetik2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    En vanlig behandling av tandlöshet i underkäken är att operera in fyra titanimplantat och på implantaten göra en tandbrygga. Om munhygienen är bristfällig kan komplikationer uppstå med risk för att implantaten lossnar. Med färre implantat skulle den risken kunna minska.

     Syftet var att konstruera och tillverka en maskin för simulering av tuggprocessen. Användningen av maskinen ska kunna avgöra om hållfastheten är tillräcklig med endast två implantat. Maskinen tillverkades enligt en kravspecifikation i verkstaden i Teknikhuset, Umeå universitet, på uppdrag av Tomas Lindh vid Institutionen för odontologi vid Umeå universitet. Maskinen skulle b la kunna belasta implantaten och tandbryggan med en kraft som maximalt kan uppkomma i underkäken på en människa, ca 1 kN.

    Maskinen konstruerades med elmotor som driver en växel med kuggremsdrift som sköter den mekaniska tuggningen. Kamhjulet bestod av fyra kammar för jämna tryckpulser. Resultatet blev en maskin med en acceptabel konstruktion som uppfyllde de ställda kraven och gav en tryckkraft från ca 350 till 1 kN beroende på hur fjäderns förspänning ställdes. Tillverkningen begränsades framför allt av ekonomi och tid, vilket gjorde att en alternativ konstruktion med vevaxel och en färdig inköpt växel inte gick att välja.

  • 138.
    Asplund, Ragnar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Analys av gränssnittet påWebDB3.02013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Webhotellsföretaget Vildmarksdata har haft för avsikt att uppdatera den kontrollpanel somderas kunder använder för att göra inställningar relaterade till saker som zoner, domäner ochepost. Kontrollpanelen har utvärderas efter webdesignprinciper, samtidigt som dess användarehar undersökts med hjälp av telefonintervjuer och webenkäter. Studien har resulterati en rad designförslag för en ny version av kontrollpanelen, en kartläggning av användarnaoch insikten att en stor del av kunderna inte känt till att kontrollpanelen funnits.

  • 139.
    Asplund, Raquel
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Evaluation of a cloud-based image analysis and image display system for medical images2015Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
  • 140.
    Ataniyazov, Ataniyaz
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Transformatorers tekniska och ekonomiska livslängd2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is performed at WSP in Skellefteå, specializing in Rönnskär Education in Skelleftehamn.

    Rönnskär’s construction began by Boliden AB in 1928 and it was ready for production in 1930. It produces copper, lead, zinc clinker, gold and silver. In 2010 Rönnskär produced 190000 tons of copper and in 2013 it produced 206 000 tons. Current number of employees is 866.

    The electricity supply of the industrial area of Rönnskär is in very high priority and transformer failures leading to lengthy downtime and expensive repairs. Power transformers must have high operational availability transformers which purchases for production must be robust.

    This is a comparative study between dry type and oil insulated transformers which summarized in form of recommendation for the future purchases.

    The work will highlight the parameters of operational availability and operational safety make calculations for rated short time currents and losses in transformers based on manufacturers data.

    The aim of this thesis is to compare various parameters of dry and oil immersed transformers from different manufacturers summarized in a comparison table according to the apparent power and voltage which shows the difference between various types of transformers.

    This work is primarily based on the theory of transformers and at the same time on continuous dialogue with the client and the transformer manufacturer.

    The recommendations should be viewed as a preliminary study, a deeper analysis and further investigation is required when purchasing transformers, depending on the circumstances and the conditions.

    An economic analysis has not been performed because of the limited information.

    Keyword for this study is AOS: Availability and Operational Safety.

  • 141.
    Ataniyazov, Ataniyaz
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Transformatorers tekniska och ekonomiska livslängd: En jämförande studie mellan torrisolerade och oljeisolerade transformatorer som resulterar i en rekommendation för framtida inköp2014Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [en]

    This thesis is performed at WSP in Skellefteå, specializing in Rönnskär Education in Skelleftehamn.

    Rönnskär’s construction began by Boliden AB in 1928 and it was ready for production in 1930. It produces copper, lead, zinc clinker, gold and silver. In 2010 Rönnskär produced 190000 tons of copper and in 2013 it produced 206 000 tons. Current number of employees is 866.

    The electricity supply of the industrial area of Rönnskär is in very high priority and transformer failures leading to lengthy downtime and expensive repairs. Power transformers must have high operational availability transformers which purchases for production must be robust.

    This is a comparative study between dry type and oil insulated transformers which summarized in form of recommendation for the future purchases.

    The work will highlight the parameters of operational availability and operational safety make calculations for rated short time currents and losses in transformers based on manufacturers data.

    The aim of this thesis is to compare various parameters of dry and oil immersed transformers from different manufacturers summarized in a comparison table according to the apparent power and voltage which shows the difference between various types of transformers.

    This work is primarily based on the theory of transformers and at the same time on continuous dialogue with the client and the transformer manufacturer.

    The recommendations should be viewed as a preliminary study, a deeper analysis and further investigation is required when purchasing transformers, depending on the circumstances and the conditions.

    An economic analysis has not been performed because of the limited information.

    Keyword for this study is AOS: Availability and Operational Safety

  • 142.
    Ataniyazov, Ataniyaz
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Underhållsarbete på krafttransformator: En studie på genomförande av underhållsarbete i transformatoranläggningen med optimeringsförslag.2014Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
  • 143.
    Augustian, Midhumol
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    ur Réhman, Shafiq
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Sandvig, Axel
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience. Norwegian University of Science and Technology (NTNU), Norway.
    Kotikawatte, Thivra
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience.
    Yongcui, Mi
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Evensmoen, Hallvard Røe
    Norwegian University of Science and Technology (NTNU), Norway.
    EEG Analysis from Motor Imagery to Control a Forestry Crane2018In: Intelligent Human Systems Integration (IHSI 2018) / [ed] Karwowski, Waldemar, Ahram, Tareq, 2018, Vol. 722, p. 281-286Conference paper (Refereed)
    Abstract [en]

    Brain-computer interface (BCI) systems can provide people with ability to communicate and control real world systems using neural activities. Therefore, it makes sense to develop an assistive framework for command and control of a future robotic system which can assist the human robot collaboration. In this paper, we have employed electroencephalographic (EEG) signals recorded by electrodes placed over the scalp. The human-hand movement based motor imagery mentalization is used to collect brain signals over the motor cortex area. The collected µ-wave (8–13 Hz) EEG signals were analyzed with event-related desynchronization/synchronization (ERD/ERS) quantification to extract a threshold between hand grip and release movement and this information can be used to control forestry crane grasping and release functionality. The experiment was performed with four healthy persons to demonstrate the proof-of concept BCI system. From this study, it is demonstrated that the proposed method has potential to assist the manual operation of crane operators performing advanced task with heavy cognitive work load.

  • 144. Avagyan, Rozanna
    et al.
    Nyström, Robin
    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.
    Westerholm, Roger
    Determination of hydroxylated polycyclic aromatic hydrocarbons by HPLC-photoionization tandem mass spectrometry in wood smoke particles and soil samples2015In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 407, no 16, p. 4523-4534Article in journal (Refereed)
    Abstract [en]

    A simple and fast method for analysis of hydroxylated polycyclic aromatic hydrocarbons using pressurized liquid extraction and high performance liquid chromatography utilizing photoionization tandem mass spectrometry was developed. Simultaneous separation and determination of nine hydroxylated polycyclic aromatic hydrocarbons and two hydroxy biphenyls could be performed in negative mode with a run time of 12 min, including equilibration in 5 min. The calibration curves were in two concentration ranges; 1-50 ng/mL and 0.01-50 mu g/mL, with coefficients of correlation R (2) > 0.997. The limits of detection and method quantification limits were in the range of 9-56 pg and 5-38 ng/g, respectively. A two-level full factorial experimental design was used for screening of conditions with the highest impact on the extraction. The extraction procedure was automated and suitable for a large number of samples. The extraction recoveries ranged from 70 to 102 % and the matrix effects were between 92 and 104 %. The overall method was demonstrated on wood smoke particles and soil samples with good analytical performance, and five OH-PAHs were determined in the concentration range of 0.19-210 mu g/g. As far as we know, hydroxylated polycyclic aromatic hydrocarbons were determined in wood smoke and soil samples using photoionization mass spectrometry for the first time in this present study. Accordingly, this study shows that high performance liquid chromatography photoionization tandem mass spectrometry can be a good option for the determination of hydroxylated polycyclic aromatic hydrocarbons in complex environmental samples.

  • 145. Avagyan, Rozanna
    et al.
    Nyström, Robin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Lindgren, Robert
    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.
    Westerholm, Roger
    Particulate hydroxy-PAH emissions from a residential wood log stove using different fuels and burning conditions2016In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 140, p. 1-9Article in journal (Refereed)
    Abstract [en]

    Hydroxylated polycyclic aromatic hydrocarbons are oxidation products of polycyclic aromatic hydrocarbons, but have not been studied as extensively as polycyclic aromatic hydrocarbons. Several studies have however shown that hydroxylated polycyclic aromatic hydrocarbons have toxic and carcinogenic properties. They have been detected in air samples in semi urban areas and combustion is assumed to be the primary source of those compounds. To better understand the formation and occurrence of particulate hydroxylated polycyclic aromatic hydrocarbons from residential wood log stove combustion, 9 hydroxylated polycyclic aromatic hydrocarbons and 2 hydroxy biphenyls were quantified in particles generated from four different types of wood logs (birch, spruce, pine, aspen) and two different combustion conditions (nominal and high burn rate). A previously developed method utilizing liquid chromatography photo ionization tandem mass spectrometry and pressurized liquid extraction was used. Polycyclic aromatic hydrocarbons were analyzed along with hydroxylated polycyclic aromatic hydrocarbons. The hydroxylated polycyclic aromatic hydrocarbon emissions varied significantly across different wood types and burning conditions; the highest emissions for nominal burn rate were from spruce and for high burn rate from pine burning. Emissions from nominal burn rate corresponded on average to 15% of the emissions from high burn rate, with average emissions of 218 mu g/MJ(fuel) and 32.5 mu g/MJ(fuel) for high burn rate and nominal burn rate, respectively. Emissions of the measured hydroxylated polycyclic aromatic hydrocarbons corresponded on average to 28% of polycyclic aromatic hydrocarbons emissions. This study shows that wood combustion is a large emission source of hydroxylated polycyclic aromatic hydrocarbons and that not only combustion conditions, but also wood type influences the emissions of hydroxylated polycyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons. There are few studies that have determined hydroxylated polycyclic aromatic hydrocarbons in emissions from wood combustion, and it is therefore necessary to further investigate the formation, occurrence and distribution of these compounds as they are present in significant amounts in wood smoke particles.

  • 146.
    Axelsson, Sebastian
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utredning av en potentiell installation av FTX-ventilation med värmeåtervinning2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The main purpose of this degree project is to study and investigate a specific existing building to contribute to promoting a sustainable future on a larger scale. At the same time, shows that in many cases it can also be profitable to invest in a new energy-efficient system. After studying the structure and existing system of the building, it was found that a new ventilation system would be relevant.

    The building holds 83 apartments on a total area of 5 474 m2 and is located in northern part of Sweden, where temperatures of -30 °C are commen during winter time. The property is currently run by an exhaust air system for transporting consumed air, fresh air flows through outside valves directly into the recidence. Because the property is located in a place where cold outdoor temperatures occur many times a year, it's unlikely to transport cold air directly into the dwelling without preheating. This means that the current district heating consumption of the radiators will achieve unacceptable high values to maintain a good indoor envirement.

    The project that has been implemented shows that there are primarily an opportunity to install an FTX system in the homes. In many cases, there are a lack of space that contradicts an installation. Apart from the space, the result shows that district heating can be reduced by up to 600 MWh per year. This would mean a saving of 411 KSEK per year for the entire property. The cost of the required material is estimated at approximately 3.1 MSEK. This means that the investment is repaid after about 7-8 years. The figures mentioned above correspond to the material package that is reported in the report's results and assumes that existing air ducts present in the accommodation today remain but expanded. The design of the proposal presented is based on a balanced ventilation with heat recovery (80 %) with separate units for each apartement.

  • 147.
    Axner, Ove
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics. Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    Andersson, Magnus
    Umeå University, Faculty of Science and Technology, Department of Physics. Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    Björnham, Oscar
    Umeå University, Faculty of Science and Technology, Department of Physics. Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    Castelain, Mickaël
    Umeå University, Faculty of Science and Technology, Department of Physics. Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    Klinth, Jeanna
    Umeå University, Faculty of Science and Technology, Department of Physics. Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    Koutris, Efstratios
    Umeå University, Faculty of Science and Technology, Department of Physics. Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    Schedin, Staffan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    Assessing bacterial adhesion on an individual adhesin and single pili level using optical tweezers 2011In: Bacterial adhesion: chemistry, biology and physics / [ed] D. Line and A. Goldman, Berlin: Springer Berlin/Heidelberg, 2011, p. 301-313Chapter in book (Refereed)
    Abstract [en]

    Optical tweezers (OT) are a technique that, by focused laser light, can both manipulate micrometer sized objects and measure minute forces (in the pN range) in biological systems. The technique is therefore suitable for assessment of bacterial adhesion on an individual adhesin-receptor and single attachment organelle (pili) level. This chapter summarizes the use of OT for assessment of adhesion mechanisms of both non-piliated and piliated bacteria. The latter include the important helix-like pili expressed by uropathogenic Escherichia coli (UPEC), which have shown to have unique and intricate biomechanical properties. It is conjectured that the large flexibility of this type of pili allows for a redistribution of an external shear force among several pili, thereby extending the adhesion lifetime of bacteria. Systems with helix-like adhesion organelles may therefore act as dynamic biomechanical machineries, enhancing the ability of bacteria to withstand high shear forces originating from rinsing flows such as in the urinary tract. This implies that pili constitute an important virulence factor and a possible target for future anti-microbial drugs.

  • 148.
    Axner, Ove
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Björnham, Oscar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Castelain, Mickael
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Koutris, Efstratios
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Schedin, Staffan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Fällman, Erik
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Andersson, Magnus
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Unraveling the secrets of bacterial adhesion organelles using single-molecule force spectroscopy2010In: Single molecule spectroscopy in chemistry, physics and biology: Nobel symposium / [ed] Gräslund, Astrid, Rigler, Rudolf & Widengren, Jerker, Springer, 2010, p. 337-362Conference paper (Refereed)
    Abstract [en]

    Many types of bacterium express micrometer-long attachment organelles (so-called pili) whose role is to mediate adhesion to host tissue. Until recently, little was known about their function in the adhesion process. Force-measuring optical tweezers (FMOT) have since then been used to unravel the biomechanical properties of various types of pili, primarily those from uropathogenic E. coli, in particular their force-vs.-elongation response, but lately also some properties of the adhesin situated at the distal end of the pilus. This knowledge provides an understanding of how piliated bacteria can sustain external shear forces caused by rinsing processes, e.g., urine flow. It has been found that many types of pilus exhibit unique and complex force-vs.-elongation responses. It has been conjectured that their dissimilar properties impose significant differences in their ability to sustain external forces and that different types of pilus therefore have dissimilar predisposition to withstand different types of rinsing conditions. An understanding of these properties is of high importance since it can serve as a basis for finding new means to combat bacterial adhesion, including that caused by antibiotic-resistance bacteria. This work presents a review of the current status of the assessment of biophysical properties of individual pili on single bacteria exposed to strain/stress, primarily by the FMOT technique. It also addresses, for the first time, how the elongation and retraction properties of the rod couple to the adhesive properties of the tip adhesin.

  • 149.
    Axner, Ove
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Björnham, Oscar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Castelain, Mickaël
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Koutris, Efstratios
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Schedin, Staffan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Fällman, Erik
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Andersson, Magnus
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Unraveling the secrets of bacterial adhesion organelles using single molecule force spectroscopy2010In: Springer series in chemical physics: single molecule spectroscopy in chemistry, physics and biology, Springer Verlag , 2010, 96, p. 337-362Chapter in book (Other academic)
    Abstract [en]

    Many types of bacterium express micrometer-long attachment organelles (so called pili) whose role is to mediate adhesion to host tissue. Until recently, little was known about their function in the adhesion process. Forcemeasuring  ptical tweezers (FMOT) have since then been used to unravel the  iomechanical properties of various types of pili, primarily those from uropathogenic E. coli, in particular their force-vs.-elongation response, but lately also some properties of the adhesin situated and the distal end of the pilus. This knowledge provides an understanding of how piliated bacteria can sustain external shear forces caused by rinsing processes, e.g. urine flow. It has been found that anytypes of pilus exhibit unique and complex force-vs.-elongation responses. It has been conjectured that their dissimilar properties impose significant differences in their ability to sustain external forces and that different types of pilus therefore have dissimilar predisposition to withstand different types of rinsing conditions. An understanding of these properties is of high importance since it can serve as a basis for finding new means to combat bacterial adhesion, including that caused by antibiotic-resistance bacteria. This work presents a review of the current status of the assessment of biophysical properties of individual pili on single bacteria exposed to strain/stress, primarily by the FMOT technique. It also addresses, for the first time, how the elongation and retraction properties of the rod couple to the adhesive properties of the tip adhesin.

  • 150.
    Ayubi, Shir Mohammad
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Modifiering av klaffskopa på uppdrag av Swekip Sweden AB2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This is a Bachelor thesis in Mechanical Engineering as a result of work situated at Swekip AB Sweden in spring 2015. The work was about reconstructing of an existing snow clearing bucket which is assembly designed in software Inventor and the product manufactures in China.Snow clearing bucket and the other parts in term of wear steels would be reconstructed and they had to follow Swedish and European standard in terms of bushing, wear resistance steel etc.The manufacturing company in China does not have the same technical possibilities as a Swedish manufacturing company. For example sheet metal bending, laser cuttings machine etc.Therefore wishes the company that the new design of snow clearing bucket leads to a simple documentation/construction design which in turn make it easier for the manufacturer production.

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