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  • Bui, Thanh
    et al.
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Jakobsson, Daniel
    Trafikverket, Sweden.
    Löfgren, Birger
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Rudmark, Daniel
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Sundström, Christofer
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Voronov, Alexey
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Vyth, Jakob
    IBM, Sweden.
    Data Driven Traffic Management Policy2020Rapport (Annet vitenskapelig)
    Abstract [en]

    Large amounts of data and information is generated for different purposes every day in the traffic system. There is an increased interest within the Swedish Transport Administration (STA) in using this data for planning of maintenance, traffic management and strategy work. In this report the first steps towards such a system is developed by the process of defining a business objective, collecting data, understand the data, prepare the data, create a model and evaluate the results. All these different steps were important in the performed study. To find a good case creating business value required lots of discussions and interviews with key figures at STA. The case investigated is to predict the traffic situation on four road segments in Gothenburg based on two years of data for the traffic situation, weather, and road situation including accidents and road works.

    The data for primarily weather and traffic are not collected for the purpose of being used for this application. This is one reason for that data is missing from some of the data sets for different time periods. One conclusion from the project is that data analysts must be included not only in the data analyze phase, but also in the data collection phase to achieve good results.

    Different methods for creating data driven models are evaluated and compared based on the two year period of data available. It is found that linear regression performs better than tree-based classification and prediction method regarding performance, while the tree-based method more clearly can create understanding for what variables that correlate to the traffic situation.

    The methods for developing models based on the data used in this project are generic and are possible to be used when larger data sets are available. Additional data sources, such as events in the city and building works may also be included in such analysis. Furthermore, it is found valuable to have the possibility to develop models on a local computer based on a smaller data set, and make the final computations based on the larger data sets in a cloud based solution.

    Fulltekst (pdf)
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  • Magnusson, Bertil
    et al.
    RISE Research Institutes of Sweden, Material och produktion, Kemi, biomaterial och textil.
    Örnemark, Ulf
    Emendo dokumentgranskning, Sweden.
    Metodvalidering : Handbok för laboratoriet: utgåva 42020Rapport (Annet vitenskapelig)
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  • Andersson Ersman, Peter
    et al.
    RISE Research Institutes of Sweden, Digitala system.
    Zabihipour, Marzieh
    Linköping University, Sweden.
    Tu, Deyu
    Linköping University, Sweden.
    Lassnig, Roman
    RISE Research Institutes of Sweden, Digitala system.
    Strandberg, Jan
    RISE Research Institutes of Sweden, Digitala system, Smart hårdvara.
    Åhlin, Jessica
    RISE Research Institutes of Sweden, Digitala system, Smart hårdvara.
    Nilsson, Marie
    RISE Research Institutes of Sweden, Digitala system, Smart hårdvara.
    Westerberg, David
    RISE Research Institutes of Sweden, Digitala system.
    Gustafsson, Göran
    RISE Research Institutes of Sweden, Digitala system.
    Berggren, Magnus
    Linköping University, Sweden.
    Forchheimer, Robert
    Linköping University, Sweden.
    Fabiano, Simone
    Linköping University, Sweden.
    Monolithic integration of display driver circuits and displays manufactured by screen printing2020Inngår i: Flexible and Printed Electronics, ISSN 2058-8585, Vol. 5, nr 2, artikkel-id 024001Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Here, we report all-screen printed display driver circuits, based on organic electrochemical transistors (OECTs), and their monolithic integration with organic electrochromic displays (OECDs). Both OECTs and OECDs operate at low voltages and have similar device architectures, and, notably, they rely on the very same electroactive material as well as on the same electrochemical switching mechanism. This then allows us to manufacture OECT-OECD circuits in a concurrent manufacturing process entirely based on screen printing methods. By taking advantage of the high current throughput capability of OECTs, we further demonstrate their ability to control the light emission in traditional light-emitting diodes (LEDs), where the actual LED addressing is achieved by an OECT-based decoder circuit. The possibility to monolithically integrate all-screen printed OECTs and OECDs on flexible plastic foils paves the way for distributed smart sensor labels and similar Internet of Things applications.

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  • Palladino, Nicoletta
    et al.
    Swedish National Heritage Board, Sweden.
    Hacke, Marei
    Swedish National Heritage Board, Sweden.
    Poggi, Giovanna
    University of Florence, Italy.
    Nechyporchuk, Oleksandr
    RISE Research Institutes of Sweden, Material och produktion, Kemi, biomaterial och textil. Chalmers University of Technology, Sweden.
    Kolman, Krzysztof
    Chalmers University of Technology, Sweden; Nouryon, Sweden.
    Xu, Qingmeng
    University of Florence, Italy.
    Persson, Michael E.
    Chalmers University of Technology, Sweden; Nouryon, Sweden.
    Giorgi, Rodorico
    University of Florence, Italy.
    Holmberg, Krister
    Chalmers University of Technology, Sweden.
    Baglioni, Piero
    University of Florence, Italy.
    Bordes, Romain
    Chalmers University of Technology, Sweden.
    Nanomaterials for combined stabilisation and deacidification of cellulosic materials: the case of iron-tannate dyed cotton2020Inngår i: Nanomaterials, ISSN 2079-4991, Vol. 10, nr 5, artikkel-id 900Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The conservation of textiles is a challenge due to the often fast degradation that results from the acidity combined with a complex structure that requires remediation actions to be conducted at several length scales. Nanomaterials have lately been used for various purposes in the conservation of cultural heritage. The advantage with these materials is their high efficiency combined with a great control. Here, we provide an overview of the latest developments in terms of nanomaterials-based alternatives, namely inorganic nanoparticles and nanocellulose, to conventional methods for the strengthening and deacidification of cellulose-based materials. Then, using the case of iron-tannate dyed cotton, we show that conservation can only be addressed if the mechanical strengthening is preceded by a deacidification step. We used CaCO3 nanoparticles to neutralize the acidity, while the stabilisation was addressed by a combination of nanocellulose, and silica nanoparticles, to truly tackle the complexity of the hierarchical nature of cotton textiles. Silica nanoparticles enabled strengthening at the fibre scale by covering the fibre surface, while the nanocellulose acted at bigger length scales. The evaluation of the applied treatments, before and after an accelerated ageing, was assessed by tensile testing, the fibre structure by SEM and the apparent colour changes by colourimetric measurements.

    Fulltekst (pdf)
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  • Kortenkamp, Andreas
    et al.
    Brunel University London, UK.
    Axelstad, Marta
    DTU Technical University of Denmark, Denmark.
    Baig, Asma H
    Brunel University London, UK.
    Bergman, Åke
    Örebro University, Sweden.
    Bornehag, Carl-Gustaf
    Karlstad University, Sweden.
    Cenijn, Peter
    Vrije Universiteit Amsterdam, The Netherlands.
    Christiansen, Sofie
    DTU Technical University of Denmark, Denmark.
    Demeneix, Barbara
    Muséum national d'Histoire naturelle, France.
    Derakhshan, Arash
    Erasmus Medical Centre, The Netherlands.
    Fini, Jean-Baptiste
    Muséum national d'Histoire naturelle, France.
    Frädrich, Caroline
    Charitė Universitätsmedizin Berlin, Germany.
    Hamers, Timo
    Vrije Universiteit Amsterdam, Netherlands.
    Hellwig, Lina
    Charitė Universitätsmedizin Berlin, Germany.
    Köhrle, Josef
    Charitė Universitätsmedizin Berlin, Germany.
    Korevaar, Tim I M
    Erasmus Medical Centre, The Netherlands.
    Lindberg, Johan
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Kemiska processer och läkemedel.
    Martin, Olwenn
    Brunel University London, UK.
    Meima, Marcel E
    Erasmus Medical Centre, Netherlands.
    Mergenthaler, Philipp
    Charité Universitätsmedizin Berlin, Germany; Berlin Institute of Health, Germany.
    Nikolov, Nikolai
    DTU Technical University of Denmark, Denmark.
    Du Pasquier, David
    Laboratoire Watchfrog, France.
    Peeters, Robin P
    Erasmus Medical Centre, The Netherlands.
    Platzack, Bjorn
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Kemiska processer och läkemedel.
    Ramhøj, Louise
    DTU Technical University of Denmark, Denmark.
    Remaud, Sylvie
    Muséum national d'Histoire naturelle, France.
    Renko, Kostja
    Charitė Universitätsmedizin Berlin, Germany.
    Scholze, Martin
    Brunel University London, UK.
    Stachelscheid, Harald
    Charité Universitätsmedizin Berlin, Germany; Berlin Institute of Health, Germany.
    Svingen, Terje
    DTU Technical University of Denmark, Denmark.
    Wagenaars, Fabian
    Vrije Universiteit Amsterdam, Netherlands.
    Wedebye, Eva Bay
    DTU Technical University of Denmark, Denmark.
    Zoeller, R Thomas
    Orebro University, Sweden.
    Removing Critical Gaps in Chemical Test Methods by Developing New Assays for the Identification of Thyroid Hormone System-Disrupting Chemicals-The ATHENA Project2020Inngår i: International Journal of Molecular Sciences, ISSN 1422-0067, E-ISSN 1422-0067, Vol. 21, nr 9, artikkel-id E3123Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The test methods that currently exist for the identification of thyroid hormone system-disrupting chemicals are woefully inadequate. There are currently no internationally validated in vitro assays, and test methods that can capture the consequences of diminished or enhanced thyroid hormone action on the developing brain are missing entirely. These gaps put the public at risk and risk assessors in a difficult position. Decisions about the status of chemicals as thyroid hormone system disruptors currently are based on inadequate toxicity data. The ATHENA project (Assays for the identification of Thyroid Hormone axis-disrupting chemicals: Elaborating Novel Assessment strategies) has been conceived to address these gaps. The project will develop new test methods for the disruption of thyroid hormone transport across biological barriers such as the blood-brain and blood-placenta barriers. It will also devise methods for the disruption of the downstream effects on the brain. ATHENA will deliver a testing strategy based on those elements of the thyroid hormone system that, when disrupted, could have the greatest impact on diminished or enhanced thyroid hormone action and therefore should be targeted through effective testing. To further enhance the impact of the ATHENA test method developments, the project will develop concepts for better international collaboration and development in the area of thyroid hormone system disruptor identification and regulation.

    Fulltekst (pdf)
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  • Zhou, Linghua
    et al.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Chen, Zhiqiang
    SLU Swedish University of Agricultural Sciences, Sweden.
    Olsson, Lars
    RISE Research Institutes of Sweden, Bioekonomi och hälsa.
    Grahn, Thomas
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Massa, papper och förpackningar.
    Karlsson, Bo
    Skogforsk, Sweden.
    Wu, Harry Xiaming
    SLU Swedish University of Agricultural Sciences, Sweden; Beijing Forestry University, China; CSIRO, Australia.
    Lundqvist, Sven Olof
    RISE Research Institutes of Sweden, Bioekonomi och hälsa. IIC, Sweden.
    García-Gil, María Rosario
    SLU Swedish University of Agricultural Sciences, Sweden.
    Effect of number of annual rings and tree ages on genomic predictive ability for solid wood properties of Norway spruce2020Inngår i: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 21, nr 1, artikkel-id 323Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Genomic selection (GS) or genomic prediction is considered as a promising approach to accelerate tree breeding and increase genetic gain by shortening breeding cycle, but the efforts to develop routines for operational breeding are so far limited. We investigated the predictive ability (PA) of GS based on 484 progeny trees from 62 half-sib families in Norway spruce (Picea abies (L.) Karst.) for wood density, modulus of elasticity (MOE) and microfibril angle (MFA) measured with SilviScan, as well as for measurements on standing trees by Pilodyn and Hitman instruments. Results: GS predictive abilities were comparable with those based on pedigree-based prediction. Marker-based PAs were generally 25-30% higher for traits density, MFA and MOE measured with SilviScan than for their respective standing tree-based method which measured with Pilodyn and Hitman. Prediction accuracy (PC) of the standing tree-based methods were similar or even higher than increment core-based method. 78-95% of the maximal PAs of density, MFA and MOE obtained from coring to the pith at high age were reached by using data possible to obtain by drilling 3-5 rings towards the pith at tree age 10-12. Conclusions: This study indicates standing tree-based measurements is a cost-effective alternative method for GS. PA of GS methods were comparable with those pedigree-based prediction. The highest PAs were reached with at least 80-90% of the dataset used as training set. Selection for trait density could be conducted at an earlier age than for MFA and MOE. Operational breeding can also be optimized by training the model at an earlier age or using 3 to 5 outermost rings at tree age 10 to 12 years, thereby shortening the cycle and reducing the impact on the tree.

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  • Larsson, Ida
    et al.
    RISE Research Institutes of Sweden, Säkerhet och transport, Brandteknik.
    Lönnermark, Anders
    RISE Research Institutes of Sweden, Säkerhet och transport, Brandteknik.
    Blomqvist, Per
    RISE Research Institutes of Sweden, Säkerhet och transport, Brandteknik.
    Zimmermann, Florian
    RISE Research Institutes of Sweden, Säkerhet och transport, Brandteknik.
    Dahlbom, Sixten
    RISE Research Institutes of Sweden, Säkerhet och transport, Brandteknik.
    Medium-scale self-heating tests with biomass pellets2020Rapport (Annet vitenskapelig)
    Abstract [en]

    A commonly known problem with storage of biomass pellets is the risk for self-heating. The propensity for self-heating depends on several parameters e.g. type of pellets, humidity, ventilation, temperature, type of storage and handling prior to storage.

    Within the framework of the research project SafePellets (Safety and quality assurance measures along the pellets supply chain) a medium-scale methodology to assess the propensity for self-heating has been developed. In addition, methods to study carbon monoxide (CO), carbon dioxide (CO2) and oxygen (O2) concentrations as well as different aldehydes have been tested and evaluated in this study.

    Biomass pellets from three different sources, i.e. 100 % pine; a mixture of spruce and pine and a mixture of straw, seed residue and spruce, were tested in a 1 m3 test container. The test container and the pellets were pre-heated and kept at the nominal test temperature until self-heating occurred, or the test was terminated. Temperatures were measured at more than 40 different positions and gas samples were extracted from the test container and analysed.

    Differences were observed as a function of pellet type, but also as a function of nominal test temperature and ventilation. Significant levels of CO and CO2 and a reduced level of O2 were observed direct after the pre-heating, indicating oxidation of the pellets. Ten different tests were made; ignition occurred in four of them. The higher the nominal test temperature, the higher propensity for self-heating. When ignition occurred, the concentrations of CO and CO2 increased rapidly. It was found that the ventilation conditions were important. In some of the tests, natural convection caused the pellet bulk to cool. In other tests, when the test container was closed, the oxygen concentration dropped, and self-heating was reduced.

    Measurements of CO, CO2 and O2 contributed with information about the tests. However, the results from aldehyde measurements were unconcise and the values have only been used as indicative. Identified aldehydes were hexanal, butyraldehyde, valeraldehyde, formaldehyde, propionaldehyde, acetaldehyde and acrolein.

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  • McConville, Jennifer R.
    et al.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Kvarnström, Elisabeth
    RISE Research Institutes of Sweden, Samhällsbyggnad, Systemomställning och tjänsteinnovation.
    Nordin, Annika C.
    SLU Swedish University of Agricultural Sciences, Sweden.
    Jönsson, Håkan
    SLU Swedish University of Agricultural Sciences, Sweden.
    Niwagaba, Charles B.
    Makerere University, Uganda.
    Structured Approach for Comparison of Treatment Options for Nutrient-Recovery From Fecal Sludge2020Inngår i: Frontiers in Environmental Science, ISSN 2296-665X, Vol. 8, artikkel-id 36Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of this study is to present a structured approach for comparing possible nutrient-recovery fecal sludge (FS) treatment systems in order to support transparent decision-making. The approach uses a multi-dimensional sustainability assessment of treatment technologies for nutrient recovery from FS, using a typical case of Kampala City, Uganda. A synthesized list of 22 treatment technologies was prepared from literature. This list included wastewater treatment technologies, which could be adapted to treat fecal sludge, and established fecal sludge treatment technologies that are available or potentially applicable in Kampala. Based on the local situation, the list was reduced to eight possible options, which were carried forward into a multi-dimensional sustainability assessment that incorporated input of stakeholders. The technologies included in the final assessment were optimization of the existing system, lactic acid fermentation (LAF), composting, vermicomposting, Black-Soldier Fly (BSF) composting, ammonia treatment, alkaline stabilization and solar drying. Optimization of the existing system performed well against the set criteria and is a recommended short-term solution. This will require e.g., adding narrower screens to remove more trash from the incoming sludge and respecting storage times prior to selling the sludge. To maximize the agricultural value of the recovered product, while respecting the need for safe reuse, a combination of technologies becomes relevant; the use of a combination of BSF, and subsequent ammonia or alkaline treatment of the remaining organic fraction would allow for maximized safe nutrient recovery and can be the aim for long-term sanitation planning in Kampala. The results of this process provide supporting information for a discussion of trade-offs between stakeholder groups as part of a decision-making process within a larger planning context.

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  • Liu, Shaoteng
    et al.
    RISE Research Institutes of Sweden, Digitala system, Datavetenskap.
    Steinert, Rebecca
    RISE Research Institutes of Sweden, Digitala system, Datavetenskap.
    Vesselinova, Natalia
    RISE Research Institutes of Sweden, Digitala system, Datavetenskap.
    Kostic, Dejan
    RISE Research Institutes of Sweden, Digitala system, Datavetenskap. KTH Royal Institute of Technology, Sweden.
    Fast Deployment of Reliable Distributed Control Planes with Performance Guarantees2020Inngår i: IEEE Access, E-ISSN 2169-3536, Vol. 8, s. 70125-70149, artikkel-id 9051708Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Current trends strongly indicate a transition towards large-scale programmable networks with virtual network functions. In such a setting, deployment of distributed control planes will be vital for guaranteed service availability and performance. Moreover, deployment strategies need to be completed quickly in order to respond flexibly to varying network conditions. We propose an effective optimization approach that automatically decides on the needed number of controllers, their locations, control regions, and traffic routes into a plan which fulfills control flow reliability and routability requirements, including bandwidth and delay bounds. The approach is also fast: The algorithms for bandwidth and delay bounds can reduce the running time at the level of 50x and 500x, respectively, compared to state-of-the-art and direct solvers such as CPLEX. Altogether, our results indicate that computing a deployment plan adhering to predetermined performance requirements over network topologies of various sizes can be produced in seconds and minutes, rather than hours and days. Such fast allocation of resources that guarantees reliable connectivity and service quality is fundamental for elastic and efficient use of network resources.

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  • Norefjäll, Fredric
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Talalasova, Elena
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Tekie, Haben
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Barriers for industrial waste recycling in the context of circular transition: lessons from Mistra Closing the Loop2019Rapport (Annet vitenskapelig)
    Abstract [en]

    This is the final deliverable from a task within the national research program Mistra Closing the Loop (CTL). It aimed at analysing the barriers and drivers for industrial waste recycling as a part of transition towards a circular society. In doing so, we drew on the experiences from five projects participating in CTL. Found below is a graphical abstract capturing both of the logic behind the research and the main results.

    Industrial recycling as part of a broader transition towards a more circular society faces an overwhelming number of obstacles on all system levels. Apart from being a source of despair, long, unprioritised lists of barriers can lead to diffusion of efforts and resources while attempting to tackle them all at once. In addition, these barriers have traditionally been regarded as separate entities, and little is known about the relationships between them. In this report, we argue for a shift in how we study and act on the barriers for circular transition. More specifically, we call for:

    • a need to better understand the links, relationships and dynamics between different barriers and barrier groups• a need for methodological experimentation and more action-oriented research• a more targeted approach, where resources are pulled towards tackling a few barriers with a scientifically demonstrated potential to accelerate the change

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  • Jendzurski, John R.
    et al.
    National Institute of Standards and Technology, USA.
    Paulter, Nicholas G.
    National Institute of Standards and Technology, USA.
    Jacobs, Eddie L.
    University of Memphis, USA.
    Amon, Francine
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Bovik, Alan Conrad
    University of Texas at Austin, USA.
    Goodall, Todd Richard
    University of Texas at Austin, USA.
    Image quality testing: Selection of images for assessing test subject input2014Inngår i: International Journal on Smart Sensing and Intelligent Systems, ISSN 1178-5608, Vol. 7, nr 5Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Determining image quality is dependent to some degree on human interpretation. Although entirely subjective methods of evaluating image quality may be adequate for consumer applications, they are not acceptable for security and safety applications where operator interpretation may lead to missing a threat or finding threats where they do not exist. Therefore, methods must be developed to ensure that the imagery used in security and safety applications are of sufficient quality to allow the operator to perform his job accurately and efficiently. NIST has developed a method to quantify the capability of imagers to provide images of sufficient quality to allow humans to perform specific perception-based tasks. A one-time humanperception based step is required that results in perception coefficients that are combined with lab-measured objective image quality indicators (IQIs) to calculate image quality. This work uses a d′ evaluation method to examine the performance of test subjects in the human-perception based step, which was identification of a fire hazard in a set of grey-scale infrared images.

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  • Brandon, Daniel
    RISE Research Institutes of Sweden, Säkerhet och transport, Brandteknik.
    Collection of Façade Fire Tests Including Timber Structures2020Rapport (Annet vitenskapelig)
    Abstract [en]

    This report describes three case studies that each involved an analysis of a fire test of an external wall that included a timber structure or part of a timber structure. These external walls all had wooden façade panels, were ventilated behind the façade panels and had glass wool or stone wool insulation. The three case studies aim to assess the contribution of structural timber to the fire development and the fire spread. In addition, the potential of façade systems with combustible materials to limit the fire spread through and along the external wall was assessed. The fire tests were performed for commercial purposes and their results were made available for this study. Not all details of the façade systems details are included in this report.

    The analysis discussed in this report indicates that the timber structures did not contribute to the fire development and the fire spread in two of the three tests. The structural members in the external wall remained unaffected during the test. Visual inspection of the third test showed locally some superficial coloring and charring. However, the temperature measurements of the remaining test did not indicate any contribution of the structural timber to the fire development and fire spread. The energy contribution corresponding to the local and superficial coloring and charring is considered negligible.

    Two of the three tests analyzed in this study were performed in accordance with the Swedish façade fire testing standard SP Fire 105. Both tests were assessed by the accredited testing institute to meet the requirements set by the Swedish Building regulations that: (1) the fire spread inside the external wall shall be limited; (2) the risk for fire spread along the façade surface shall be limited and; (3) the risk for injuries as a consequence of falling parts from the external wall shall be limited.

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  • Ernits, Heiti
    RISE Research Institutes of Sweden, Samhällsbyggnad, Systemomställning och tjänsteinnovation. University of Borås, Sweden.
    Ledarskap i mellanrummen – fallstudie av gränsgångare och gränspraktiker i en komplex samverkansmiljö2020Licentiatavhandling, monografi (Annet vitenskapelig)
    Abstract [sv]

    Gränsöverskridande samarbete, samverkan och tidsbegränsade arbetssätt är på modet. Stadsplanering, samhällsstyrning, välfärdsproduktion och tackling av samhälleliga utmaningar sker allt mer i projektform och inkluderar en blandning av offentliga verksamheter, privata aktörer och intressenter. Så kallad gränsöverskridande organisering sker över olika typer av professionella, organisatoriska, geografiska och institutionella gränser. Denna trend har även inneburit ett ökat intresse för gränsgångare och olika typer av gränspraktiker som enligt studier spelar en allt viktigare roll i gränsöverskridande samverkansmiljöer. Denna studie söker svar på hur en gränsgångarpraktik kommer till uttryck i en samverkansmiljö, vilka problem som uppstår och på vilket sätt praktiken eventuellt bidrar till samverkan. Studien har fokuserat på projektet

    Kraftsamling Sjöbo som har pågått sedan december 2017. I Kraftsamlingen deltar offentliga verksamheter, civilsamhället, myndigheter, föreningar, akademin, forskningsinstitut och invånare. Syftet är en hållbar omställning av en stadsdel. För det första visar studien att det krävdes en omfattande arbetsinsats för att åstadkomma ett fungerande samarbete över gränser. Det gränsöverskridande samarbetet försvårades delvis på grund av skillnader i kultur, intressen, värderingar och organisatoriska förutsättningar. För det andra visar studien att projektledarrollen förändrades och arbetet med Kraftsamlingen visade sig kräva omfattande gränsöverskridande interaktion, facilitering och ständigt pågående problemlösning. Gränsgångaren trädde in i en ledarskapsroll när situationer krävde det och arbetade aktivt för att skapa strukturella förutsättningar för att åstadkomma fungerande samarbete, baserat på Kraftsamlingens mission och värden. Gränsgångarpraktiken visade sig vara komplex och mångfacetterad. Gränsgångaren kopplade exempelvis samman aktörer, byggde sociala nätverk, mobiliserade resurser, försökte påverka rådande tanke- och arbetssätt, förflyttade information över gränser, agerade som översättare mellan professionella gemenskaper, löste uppblossande konflikter, skapade nya organisatoriska strukturer, försökte skapa engagemang och drev på för kollektiv handling. Gränsgångaren försökte etablera en gemensam samverkanskultur och arbetade aktivt med de sociala sammanhangen i organisationen.

    För det tredje indikerar studien att den här typen av gränsöverskridande ledarskapspraktik spelar en viktig roll i gränsöverskridande samverkansmiljöer där en mångfald av aktörer som har olika förutsättningar och intressen deltar. Studien illustrerar även de utmaningar som ett projektbaserat arbetssätt kan innebära när gränser korsas och när frågorna som hanteras är komplexa och sammansatta. Studiens resultat kan också omsättas till ett antal praktiska rekommendationer. För det första bör synen på projektledarskapet i komplexa samverkansprojekt nyanseras och utvidgas. För det andra bör gränsgångarroller och det informella ledarskapet synliggöras och uppvärderas i samverkansmiljöer. För det tredje bör de specifika kompetenserna och det nödvändiga sociala hantverket synliggöras och inkluderas i rekryteringsarbetet hos organisationer.

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  • von Platten, Jenny
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Systemomställning och tjänsteinnovation. Lund University, Sweden.
    Sandels, Claes
    RISE Research Institutes of Sweden, Säkerhet och transport, Mätteknik.
    Jörgensson, Kajsa
    Lund University, Sweden.
    Karlsson, Viktor
    Lund University, Sweden.
    Mangold, Mikael
    RISE Research Institutes of Sweden, Samhällsbyggnad, Systemomställning och tjänsteinnovation.
    Mjörnell, Kristina
    RISE Research Institutes of Sweden, Säkerhet och transport. Lund University, Sweden.
    Using Machine Learning to Enrich Building Databases—Methods for Tailored Energy Retrofits2020Inngår i: energies, E-ISSN 1996-1073, Vol. 13, nr 10Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Building databases are important assets when estimating and planning for national energy savings from energy retrofitting. However, databases often lack information on building characteristics needed to determine the feasibility of specific energy conservation measures. In this paper, machine learning methods are used to enrich the Swedish database of Energy Performance Certificates with building characteristics relevant for a chosen set of energy retrofitting packages. The study is limited to the Swedish multifamily building stock constructed between 1945 and 1975, as these buildings are facing refurbishment needs that advantageously can be combined with energy retrofitting. In total, 514 ocular observations were conducted in Google Street View of two building characteristics that were needed to determine the feasibility of the chosen energy retrofitting packages: (i) building type and (ii) suitability for additional façade insulation. Results showed that these building characteristics could be predicted with an accuracy of 88.9% and 72.5% respectively. It could be concluded that machine learning methods show promising potential to enrich building databases with building characteristics relevant for energy retrofitting, which in turn can improve estimations of national energy savings potential.

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  • Francart, Nicolas
    et al.
    KTH Royal Institute of Technology, Sweden.
    Höjer, Mattias
    KTH Royal Institute of Technology, Sweden.
    Mjörnell, Kristina
    RISE Research Institutes of Sweden, Säkerhet och transport. Lund University, Sweden.
    Sargon Orahim, Allanmikel
    RISE Research Institutes of Sweden, Samhällsbyggnad, Systemomställning och tjänsteinnovation.
    von Platten, Jenny
    RISE Research Institutes of Sweden, Samhällsbyggnad, Systemomställning och tjänsteinnovation. Lund University, Sweden.
    Malmqvist, Tove
    KTH Royal Institute of Technology, Sweden.
    Sharing indoor space: stakeholders’ perspectives and energy metrics2020Inngår i: Buildings and Cities, Vol. 1, nr 1, s. 70-85Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The sharing of indoor space can improve space and energy efficiency. The drivers and barriers to space-sharing initiatives are investigated from the perspectives of building users and building sector practitioners, based on interviews and a workshop. The role of energy performance metrics in promoting space efficiency is further analysed through a literature review. From the users’ perspective, space sharing can be understood through the interplay between tangible aspects (e.g. concrete benefits derived from sharing), organisational aspects (e.g. common decision processes and conflict resolution) and social aspects (e.g. group identity and consensus on appropriate behaviours). From the perspective of architects and property owners, shareable spaces require features such as flexibility and multifunctionality. The design of such spaces is limited by regulatory issues (e.g. building regulations poorly accommodate shared facilities) and business-related issues. One such issue is that building performance metrics normalised based on floor area do not incentivise the efficient use of space. A review of complementary metrics is provided, covering parameters such as number of users, layout, time of use, etc. Each metric serves a particular purpose; therefore, a set of complementary metrics can be used to support decisions at different phases of the building’s life cycle.

    Practice relevanceImproving space efficiency (e.g. by sharing indoor space) is a key strategy to meet simultaneously the future demand for facilities in cities and fulfil environmental objectives such as a reduction of climate change impact in the building sector. A clearer understanding of the specificities of space sharing is provided from the perspectives of building users and practitioners. This will assist practitioners to understand the needs of other stakeholders. Regulatory and business-related barriers to space-sharing initiatives are highlighted as a first step towards overcoming these barriers. Guidance is provided on complementary energy performance metrics appropriate for space efficiency. These metrics can be used to support various decisions during the different stages of a building’s life cycle.

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  • Chen, Siqian
    et al.
    University of Queensland, Australia; Dongguan University of Technology, China.
    Lopez-Sanches, Patricia
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Jordbruk och livsmedel.
    Wang, Dongjie
    University of Queensland, Australia; Tianjin University of Science and Technology, China.
    Mikkelsen, Deirdre
    University of Queensland, Australia.
    Gidley, Michael John
    University of Queensland, Australia.
    Mechanical properties of bacterial cellulose synthesised by diverse strains of the genus Komagataeibacter2018Inngår i: Food Hydrocolloids, ISSN 0268-005X, E-ISSN 1873-7137, Vol. 81, s. 87-95Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Bacterial cellulose (BC) has several current and potential future uses in the food industry because of its ability to form hydrogels with distinctive properties. The texture of BC hydrogels is determined by both the cellulose fibre network and the internal dispersed water. In this study, mechanical properties of hydrated BC synthesised by six different strains of Komagataeibacter genus were investigated with regards to their extensibility, compressive strength, relaxation ability, viscoelasticity and poroelasticity. The stress/strain at failure and Young's modulus were assessed by uniaxial tensile testing. The compressive strength, relaxation ability and viscoelasticity were measured via a series of compression and small amplitude oscillatory shear steps. A poroelastic constitutive modelling simulation was used to investigate the mechanical effects of water movement. The morphology of the BC fibril network under compression was observed via scanning electron microscopy. Results showed that the mechanics of BC were highly dependent on the cellulose concentration, as well as the morphology of the fibril network. BC synthesised by ATCC 53524 was the most concentrated (0.71 wt%), and exhibited high tensile properties, stiffness and storage moduli; whereas comparatively low mechanical properties were noted for BC produced by ATCC 700178 and ATCC 10245, which contained the lowest cellulose concentration (0.18 wt%). Small deformation responses (normal stress, G′) scaled with cellulose concentration for all samples, whereas larger deformation responses (Young's modulus, poroelasticity) depended on both cellulose concentration and additional factors, presumably related to network morphology. Increasing concentration and compressive coalescence of fibres in the integrated BC network reduced both the relaxation of the normal stress and the movement of water. This research aids the selection of bacterial strains to modulate the texture and mechanical properties of hydrated BC-based food systems.

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  • Ström, Tomas
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, SP Sveriges tekniska forskningsinstitut / Akustik (Eta).
    Vägtrafikbuller - bestämning av mätosäkerhet: Nordtest projekt 1273-961997Rapport (Annet vitenskapelig)
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  • Sandin, Ylva
    et al.
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Sandin, Gustav
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Cristescu, Carmen
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Olsson, Jörgen
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Kunskapsläge kring byggnader med stomme av trä: teknik, hållbarhet och cirkulär materialanvändning2020Rapport (Annet vitenskapelig)
    Abstract [sv]

    Byggandet står för en betydande resursanvändning och miljöbelastning. Att uppföra en större andel av byggnadsstommarna av trä har lyfts som ett möjligt sätt att bidra till ett mer hållbart byggande. Städer har engagerat sig i byggande med trä genom att anta särskilda träbyggnadsstrategier. För att fatta välinformerade beslut om val av byggnadsstommar behöver beslutsfattare vetenskapligt grundade kunskaper. Det saknas i litteraturen ett sammanställt vetenskapligt kunskapsunderlag vad gäller trästommars tekniska prestanda och hållbarhet. Den här rapportens syfte är att utgöra ett sådant underlag.

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  • Johansson, Pernilla
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Ekstrand-Tobin, Annika
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Sikander, Eva
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Hantering och urval av trämaterial avsett för återanvändning: Vad man bör tänka på för att undvika mödelskadat material1999Rapport (Annet vitenskapelig)
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  • Larsson, Stig
    et al.
    RISE Research Institutes of Sweden, Digitala system, Industriella system.
    Harlin, Ulrika
    RISE Research Institutes of Sweden, Material och produktion, Metodik för produktframtagning.
    Winzenburg, Susanna
    RISE Research Institutes of Sweden, Digitala system, Smart hårdvara.
    Edström, Adam
    RISE Research Institutes of Sweden, Digitala system, Smart hårdvara. RISE Research Institutes of Sweden, Digitala system, Prototypande samhälle.
    Färdplan: Teknik, material och förmågor för hållbar industriell konkurrenskraft2020Rapport (Annet vitenskapelig)
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  • Casimir, Justin
    et al.
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Jordbruk och livsmedel.
    Lund, Johanna
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Jordbruk och livsmedel.
    A roadmap to develop Integrated Biomass Logistic Centres in Skåne Sweden - Case study grain milling industry2020Rapport (Annet vitenskapelig)
    Abstract [en]

    This report presents the results from the EU project AGROinLOG (Grant Agreement 727921) and focuses on the development of a roadmap for the grain processing industry to develop Integrated Biomass Logistic Centres in Skåne. More information concerning the Swedish contribution can be found in the public report AGROinLOG (2020a).The Swedish partners of the AGROinLOG project have been interacting with different stakeholders from the grain processing industry in Skåne (South of Sweden) to investigate the existing hinders and drivers for the development of Integrated Biomass Logistic Centres (IBLC) in the region. This report focuses in particular into the milling industry in Skåne in regard to its potential, the utilization of the by-product bran and limitation for the implementation of IBLC. The objective of this reports is to propose a roadmap for the transformation of the current milling sector into an IBLC.The reader will first get a brief introduction to the IBLC concept and a detailed status of the cereal production and milling industry in Skåne. The process for data collection included many interactions with the industry and other relevant stakeholders. The results are then presented.The roadmap uses a backcasting approach starting with the development of a desired sustainable vision of the future. The vision foreseen that mills have developed into IBLCs and collaborate with many actors to produce a wider range of products and add values to other by-products than the mills’ own by-products. This new activity is profitable for the mills but also for other processing industries. The products developed are highly demanded by the consumers.The authors then mapped the current situation looking in particular at hinders, potential conflict of interest, and policy support. The hinders could be clustered into six categories: supply, communication, regulation, economy, market, and logistic. The conflict of interest for the valorisation of bran is low as it is used for human consumption to a low extent. It could however conflict with the animal feeding industry. Different kind of supports are needed at the different stage of the innovation development. Skåne, and Sweden in general have good access to supporting schemes. More technical data concerning the current status of the milling sector is included in the background chapter.Finally, concrete measures for moving from the current situation to the vision are discussed. The most important measure to implement would be to develop a market for the new bio-based products. To support this, a number of measures should be implemented in a joint effort. These measures include technical development, collaboration, and communication. Moreover, sustainability must be a red thread in this transformation, and new legislation should provide a supportive framework.

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  • Casimir, Justin
    et al.
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Jordbruk och livsmedel.
    Gunnarsson, Carina
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Jordbruk och livsmedel.
    Farmers current practices, and their opinion on supplying straw for production of second-generation biofuels in Sweden2020Rapport (Annet vitenskapelig)
    Abstract [en]

    This report presents results from the EU project AGROinLOG (Grant Agreement 727921) and especially focuses on the results from a survey looking at the current practices with straw use in Sweden as well as the farmer’s opinion on supplying straw for the production of second-generation biofuel. The survey was developed as a collaboration between LRF (Federation of Swedish farmers) RISE and Lantmännen.The reader can first read about the context within which the survey was developed and analysed. The questions and the methodology are then presented. The main part of the report presents the questionnaire results before drawing conclusions in line with the project’s objectives.The survey shows that about 60% of the straw from farmers participating in the survey, remains in the field while 40% is harvested mostly for animal production. The county of Skåne, the “ÖSÖ” region (Östergötland, Södermanland, and Örebro counties), the region including Uppsala, Stockholm and Västmanland counties, and the county of Västra Götaland have the largest potential for collection of straw for industrial processes in Sweden. However, farmers from these regions are the most concerned about the decrease of soil quality due to straw removal. The current common practices for straw handling in Sweden, including baling, collection, transport, storage and sale, are highlighted.Some interesting conclusions are drawn concerning the logistics needed for the handling of straw for the biobased industry. Moreover, the answers from the survey give some insights concerning a potential “straw contract” between Lantmännen and the farmers. The report also highlights the aspects to be further researched.More information concerning the Swedish contribution to the AGROinLOG project can be found in the public report AGROinLOG (2020a).

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  • Magnusson, Bertil
    et al.
    Trollboken AB, Sweden.
    Näykki,, Teemu
    SYKE, Finland.
    Hovind, Håvard
    NIVA, Norway.
    Krysell, Mikael
    Swedish Agency for Marin and Water Management, Sweden.
    Sahlin, Eskil
    RISE - Research Institutes of Sweden (2017-2019).
    Handbok för beräkning av mätosäkerhet vid miljölaboratorier: Utgåva 4.  Översättning av Nordtest TR537,2017Rapport (Annet vitenskapelig)
    Abstract [sv]

    Det är nu vanligt att använda data från kvalitetskontroll och validering för att beräkna mätosäkerhet för rutinanalyser. Nordtest handbok, TR537 som beskriver detta, finns nu tillgänglig på flera språk på www.nordtest.info. Första utgåvan kom 2003 och denna reviderade utgåva 4, baseras på erfarenhet från många laboratorier som använt detta sätt att beräkna mätosäkerhet. Viktiga uppdateringar är: • Osäkerhet över hela mätområdet – ett separat kapitel har lagts till som behandlar mätosäkerhet över mätområdet, antingen absolut eller relativ mätosäkerhet. • Beräkning av standardavvikelse från duplikat – en sammanvägd standardavvikelse används istället för en faktor gånger medelvärdet av variationsvidden. • Harmonisering med ISO11352

    Water quality – Estimation of measurement uncertainty based on validation and quality control data. Terminologin har harmoniserats med denna ISO standard som beskriver detta sätt att beräkna mätosäkerhet.

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  • Larsson, Stig
    et al.
    RISE Research Institutes of Sweden, Digitala system, Industriella system.
    Harlin, Ulrika
    RISE Research Institutes of Sweden, Material och produktion, Metodik för produktframtagning.
    Winzenburg, Susanna
    RISE Research Institutes of Sweden, Digitala system, Smart hårdvara.
    Edström, Adam
    RISE Research Institutes of Sweden, Digitala system, Prototypande samhälle.
    Färdplan: Teknik, material och förmågor för hållbar industriell konkurrenskraft (Broschyr)2020Annet (Annet vitenskapelig)
    Abstract [sv]

    De närmaste 15 åren kommer svenskindustri att med förnyad kraft fortsätta sin digitala omställning, ta tillsig en rad nya material, utveckla nyaaffärsmodeller och öka sin transformationsförmåga. Allt för att stärkasin konkurrenskraft, i symbios medhållbarhet – ekonomisk, ekologisk ochsocial. Coronapandemin medför förvisso enorma utmaningar för industrin,men efter den akuta kris hanteringenkommer med all sannolikhetindustriomställningen att ta ny fart.

    Denna broschyr är en förkortad sammanställning av RISE rapport 2020:46 som finns på länken:http://urn.kb.se/resolve?urn=urn:nbn:se:ri:diva-44978

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  • Mukkavaara, Jani
    et al.
    Luleå University of Technology, Sweden.
    Sandberg, Marcus
    Luleå University of Technology, Sweden.
    Sandberg, Karin
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Pousette, Anna
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Noren, Joakim
    RISE Research Institutes of Sweden, Samhällsbyggnad, Bygg och fastighet.
    Sustainability evaluation of timber dwellings in the north of Swedenbased on environmental impact and optimization of energy and cost2020Inngår i: Procedia Manufacturing, E-ISSN 2351-9789, Vol. 44, s. 76-83Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    optimization. From the resulting Pareto-solutions, selecting a single optimal solution remains a challenge. Thus, research is stillneeded to increase the practical use of optimization for architectural, engineering and construction (AEC) practitioners. Thispaper presents the use of an optimization approach where the results and an environmental assessment are discussed with AECpractitioners. The method was tested in two case studies: a prestige tourist cottage and a multifamily residential building.Different superstructures, insulation materials and windows were varied for the cottage’s envelope whilst evaluating life-cycleenergy and cost. In addition, the environmental impact in terms of CO2 emissions was evaluated for the initial and optimal designsuggestions for the two different superstructures. For the residential building, the insulation material thickness and the windowswere varied for its evaluation of life-cycle energy and cost. For the cottage, a report was written and then read by the practitionersand used as a base for future decisions. For the residential building, the results were presented orally for the practitioners. In bothcases, it was possible to communicate the overarching results of the optimizations through visual plots, although future researchshould find ways to also explain the detailed results.

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  • Enerbäck, Oscar
    et al.
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Malmsten Lundgren, Victor
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Alfredsson, Hampus
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    Dolins, Sigma
    RISE Research Institutes of Sweden, Digitala system, Mobilitet och system.
    S3 – Shared Shuttle Services: Fas 1 (2017-05-03 – 2019-12-31)2020Rapport (Annet vitenskapelig)
    Abstract [sv]

    S3-projektet handlar om att testa delade, elektrifierade och automatiserade skyttelbussar för att demonstrera hur dessa nya transportlösningar kan stimulera och stödja en förtätning av staden.Inom projektet har stadsutvecklare, näringsliv, akademi och offentlig sektor samlats för att gemensamt utforma och prova nya mobilitetskoncept för den första- och sista kilometern av resan. Rapporten beskriver den första fasen av projektet, från maj 2017 till och med december 2019, där skyttelbussarna testats vid Lindholmen Science Park, Chalmers campus Johanneberg samt i Härryda centrum. För att stärka projektet har arbete även utförts kring kompletterande mobilitetstjänster, öppen innovation, utvärdering, affärsmodell, färdplan, molninfrastruktur samt event och kommunikation kopplat till initiativet. Efter utmanande processer av projektering och tillståndsansökan lyckades testerna genomföras på vad som av teknik- och fordonsleverantörerna ansågs vara den mest utmanande rutten i världen som dessa fordon hittills kört på. Samtidigt är mognadsgraden för teknik och helhetstjänst fortfarande relativt låg, och kombinerat med givna säkerhetsprioriteringar lämnas en del att önska vad gäller grundläggande parametrar som hastighet och komfort. Dessutom innebär nuvarande tillståndskrav på säkerhetsoperatör ombord på fordonen begränsningar vad gäller till exempel hållbara affärsmodeller och möjligheten att studera vissa användarförhållanden. Tack till medverkande parter och finansiärer med ett särskilt tack till Vinnova, Drive Sweden och Lindholmen Science Park som gjort detta projekt möjligt. Tack till Transportstyrelsen, Trafikkontoret, Polisen och Chalmersfastigheter för snabba beslutsvägar och till Atrium Ljungberg för lånet av garageplats. Slutligen önskar projektet rikta ett stort tack till samtliga som varit med och testat skyttlarna.

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  • Ollas, Patrik
    RISE Research Institutes of Sweden, Samhällsbyggnad, Energi och resurser. Chalmers University of Technology, Sweden.
    Energy Savings Using a Direct Current Distribution Network in a PV and Battery Equipped Residential Building2020Licentiatavhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    Energy from solar photovoltaic (PV) are generated as direct current (DC) and almost all of today’s electrical loads in residential buildings, household appliances and HVAC system (Heating Ventilation and Air-conditioning) are operated on DC. For a conventional alternating current (AC) distribution system this requires the need for multiple conversion steps before the final user-stage. By switching the distribution system to DC, conversion steps between AC to DC can be avoided and, in that way, losses are reduced. Including a battery storage–the system’s losses can be reduced further and the generated PV energy is even better utilised.

    This thesis investigates and quantifies the energy savings when using a direct current distribution topology in a residential building together with distributed energy generation from solar photovoltaic and a battery storage. Measured load and PV generation data for a single-family house situated in Borås, Sweden is used as a case study for the analysis. Detailed and dynamic models–based on laboratory measurements of the power electronic converters and the battery–are also used to more accurately reflect the system’s dynamic performance.

    In this study a dynamic representation of the battery’s losses is presented which is based on laboratory measurements of the resistance and current dependency for a single lithium-ion cell based on Lithium iron phosphate (LFP). A comparative study is made with two others, commonly used, loss representations and evaluated with regards to the complete system’s performance, using the PV and load data from the single-family house. Results show that a detailed battery representation is important for a correct loss prediction when modelling the interaction between loads, PV and the battery.

    Four DC system topologies are also modelled and compared to an equivalent AC topology using the experimental findings from the power electronic converters and the battery measurements. Results from the quasi-dynamic modelling show that the annual energy savings potential from the suggested DC topologies ranges between 1.9–5.6%. The DC topologies also increase the PV utilisation by up to 10 percentage points, by reducing the associated losses from the inverter and the battery conversion. Results also show that the grid-tied converter is the main loss contributor and when a constant grid-tied efficiency is used, the energy savings are overestimated.

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