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  • 151.
    Carling, Kenneth
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Human Geography.
    A compelling argument for the gravity p-median model2013In: European Journal of Operational Research, ISSN 0377-2217, E-ISSN 1872-6860, Vol. 226, no 3, p. 658-660Article in journal (Refereed)
    Abstract [en]

    The p-median model is used to locate P facilities to serve a geographically distributed population. Conventionally, it is assumed that the population always travels to the nearest facility. Drezner and Drezner (2006, 2007) provide three arguments on why this assumption might be incorrect, and they introduce the extended gravity p-median model to relax the assumption. We favour the gravity p-median model, but we note that in an applied setting, the three arguments are incomplete. In this communication, we point at the existence of a fourth compelling argument for the gravity p-median model.

  • 152.
    Carling, Kenneth
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Human Geography.
    Jia, Tao
    School of Remote Sensing and Information Engineering, Wuhan University.
    Out-of-town shopping and its induced CO2-emissions2013Report (Other academic)
    Abstract [en]

    Planning policies in several European countries have aimed at hindering the expansion of out-of-town shopping centers. One argument for this is concern for the increase in transport and a resulting increase in environmental externalities such as CO2-emissions. This concern is weakly founded in science as few studies have attempted to measure CO2-emissions of shopping trips as a function of the location of the shopping centers. In this paper we conduct a counter-factual analysis comparing downtown, edge-of-town and out-of-town shopping. In this comparison we use GPS to track 250 consumers over a time-span of two months in a Swedish region. The GPS-data enters the Oguchi’s formula to obtain shopping trip-specific CO2-emissions. We find that consumers’ out-of-town shopping would generate an excess of 60 per cent CO2-emissions whereas downtown and edge-of-town shopping centers are comparable.

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  • 153.
    Carling, Kenneth
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Human Geography.
    Jia, Tao
    School of Remote Sensing and Information Engineering, Wuhan University.
    Out-of-town shopping and its induced CO2-emissions2013In: Journal of Retailing and Consumer Services, ISSN 0969-6989, E-ISSN 1873-1384, Vol. 20, no 4, p. 16p. 382-388Article in journal (Refereed)
    Abstract [en]

    Planning policies in several European countries have aimed at hindering the expansion of out-of-town shopping centers. One argument for this is concern for the increase in transport and a resulting increase in environmental externalities such as CO2-emissions. This concern is weakly founded in science as few studies have attempted to measure CO2-emissions of shopping trips as a function of the location of the shopping centers. In this paper we conduct a counter-factual analysis comparing downtown, edge-of-town and out-of-town shopping. In this comparison we use GPS to track 250 consumers over a time-span of two months in a Swedish region. The GPS-data enters the Oguchi’s formula to obtain shopping trip-specific CO2-emissions. We find that consumers’ out-of-town shopping would generate an excess of 60 per cent CO2-emissions whereas downtown and edge-of-town shopping centers are comparable.

  • 154.
    Carling, Kenneth
    et al.
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Meng, Xiangli
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Rudholm, Niklas
    Dalarna University, School of Technology and Business Studies, Economics. HUI Research, Stockholm.
    The effect on CO2 emissions of taxing truck distance in retail transports2017In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 97, p. 47-54Article in journal (Refereed)
    Abstract [en]

    To finance transportation infrastructure and to address social and environmental negative externalities of road transports, several countries have recently introduced or consider a distance based tax on trucks. In competitive retail and transportation markets, such tax can be expected to lower the demand and thereby reduce CO2 emissions of road transports. However, as we show in this paper, such tax might also slow down the transition towards e-tailing. Considering that previous research indicates that a consumer switching from brick-and-mortar shopping to e-tailing reduces her CO2 emissions substantially, the direction and magnitude of the environmental net effect of the tax is unclear. In this paper, we assess the net effect in a Swedish regional retail market where the tax not yet is in place. We predict the net effect on CO2 emissions to be positive, but off-set by about 50% because of a slower transition to e-tailing.

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  • 155.
    Carling, Kenneth
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Information Systems.
    Meng, Xiangli
    Dalarna University, School of Technology and Business Studies, Statistics.
    Rudholm, Niklas
    Dalarna University, School of Technology and Business Studies, Economics.
    The effects of taxing truck distance on CO2 emissions from transports in retailing2015Report (Other academic)
    Abstract [en]

    To finance transportation infrastructure and to address social and environmental negative externalities of road transports, several countries have recently introduced or consider a distance based tax on trucks. In the competitive retail market such tax can be expected to lower the demand and thereby reduce CO2 emissions of road transports. However, as we show in this paper, such tax might also slow down the transition towards e-tailing. Considering that previous research indicates that a consumer switching from brick-and-mortar shopping to e-tailing reduces her CO2 emissions substantially, the direction and magnitude of the environmental net effect of the tax is unclear. In this paper, we assess the net effect in a Swedish regional retail market where the tax not yet is in place. We predict the net effect on CO2 emissions to be positive, but off-set by about 50% because of a slower transition to e-tailing.

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  • 156.
    Carlsson, Per
    et al.
    Dalarna University, School of Technology and Business Studies, Material Science.
    Bexell, Ulf
    Dalarna University, School of Technology and Business Studies, Material Science.
    Olsson, Mikael
    Dalarna University, School of Technology and Business Studies, Material Science.
    Klang, Hans
    A study of the initial stages of atmospheric corrosion of formed hot dip zinc coated steel1997In: EUROCORR-97, Trondheim, Norway, 1997Conference paper (Other academic)
    Abstract [en]

    Hot-dip zinc coated steel sheet is extensively used to improve the corrosion protection of steel constructions. When the sheet is formed cracks in the zinc coating develop in strained areas. The zinc coating gives a galvanic protection of the steel in damaged areas of the coating and at cut edges of the sheet. The degree of protection is, however, dependent on factors such as the geometry and the area of the defects, the coating thickness, the presence of corrosive ions in the electrolyte and the wet time. In this work we have studied the initial atmospheric corrosion of zinc coated steel in defects on bended and scribed material. The samples were exposed to a cyclic indoor corrosion test developed by Volvo (Volvo standard 1027). Scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS) and Auger electron spectroscopy (AES) were used to monitor the initial stages of corrosion and the growth of corrosion products. The corrosion products were identified as predominantly zinc hydroxycarbonate, zinc hydroxychloride and zinc hydroxide. The amount of corrosion products increases with the size of the damaged area, which suggests that the cathodic reduction of oxygen at the steel substrate controls the corrosion rate.

  • 157. Carlsson, Per
    et al.
    Olsson, Mikael
    Dalarna University, School of Technology and Business Studies, Material Science.
    PVD coatings for sheet metal forming: a tribological evaluation2006In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 200, no 14-15, p. 4654-4663Article in journal (Refereed)
    Abstract [en]

    The use of liquid-based lubricants in sheet metal forming mutually has a negative impact on the environment and on the whole economy, and, consequently, there is an urgent need to find a solution to make the forming processes dry or nearly dry. The deposition of a low-friction PVD coating on the forming tool has during the last years proved to be an interesting choice when it comes to create an “unlubricated” forming process. In the present study, five different PVD coatings (one CrN and four metal-carbide-doped DLC coatings) have been evaluated in sliding contact against hot dip Zn and 55% Al–Zn-coated steel sheet using a ball-on-disc test. From the investigation, it was found that all DLC coatings have potential to prevent material pickup during dry forming of hot dip Zn-coated steel. However, the as-deposited surface morphology, showing surface irregularities such as droplets and dimples, of the coatings will strongly influence the tribological performance, and, consequently, a polishing treatment or a running-in process, resulting in a smooth surface, will significantly reduce the tendency to material pickup. In sliding contact against 55% Al–Zn-coated steel, all PVD coatings display material pickup and high friction values, the only exception being a CrC-doped DLC coating in the as-polished condition. The CrN coating showed poor performance in sliding contact against both steel sheet materials due to a high tendency to material pickup. The study focuses on the tribo-induced changes of the surface condition of the PVD coating and the steel sheet surface during the sliding event. The changes in surface chemistry and topography of the tribo surfaces were characterised using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), Auger electron spectroscopy (AES) and light interference profilometry.

  • 158. Carlucci, S.
    et al.
    De Simone, M.
    Firth, S. K.
    Kjærgaard, M. B.
    Markovic, R.
    Rahaman, M. S.
    Annaqeeb, M. K.
    Biandrate, S.
    Han, Mengjie
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    van Treeck, C.
    Modeling occupant behavior in buildings2020In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 174, article id 106768Article in journal (Refereed)
  • 159.
    Cederberg, Emil
    Dalarna University, School of Technology and Business Studies, Materials Technology.
    Utredning om alternativ kontrollmetod av härdresultat hos martensitiskt rostfritt stål2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Morakniv AB is a company that produces knives and ice drill bits. The quality of the material and heat treatment process is an important factor when the products are used in environments where the demand for performance is important. To further verify the quality, in addition to the ordinary hardness testing, they wanted to investigate an alternative test method.

    The tests included one type of material that would be heat treated in four different ways in order to evaluate the mechanical tests. The hardening process was carried out by two different austenitizing temperatures and by two different cooling rates. The hardening process took place in a belt furnace where the samples were continuously fed, heated and cooled in air. After cooling there was a sub-zero treatment followed by tempering. The results were then evaluated by bending test, hardness test and optical microscopy.

    The result showed that a hardening temperature of

    T+10 °C gave a larger standard deviation and higher ductility than at T-normal with respect to the maximum deflection. A lower cooling rate tended to decrease the maximum deflection and reduce the standard deviation. The hardness values did not vary significantly and the standard deviation were considered as negligible. The microscopy images did not show any specific structure changes when comparing the samples from the different heat treatment settings.

  • 160.
    Cedervall, Ylva
    et al.
    Institutionen för folkhälso- och vårdvetenskap, Geriatrik, Uppsala universitet.
    Halvorsen, Kjartan
    Department of Information Technology, Division of Systems and Control, Uppsala University.
    Åberg, Anna Cristina
    Department of Public Health and Caring Sciences/Geriatrics, Uppsala University.
    A longitudinal study of gait function and characteristics of gait disturbances in individuals with Alzheimer's disease2014In: Gait & Posture, ISSN 0966-6362, E-ISSN 1879-2219, Vol. 39, no 4, p. 1022-1027Article in journal (Refereed)
    Abstract [en]

    Walking in daily life places high demands on the interplay between cognitive and motor functions. A well-functioning dual-tasking ability is thus essential for walking safely. The aims were to study longitudinal changes in gait function during single- and dual-tasking over a period of two years among people with initially mild AD (n = 21). Data were collected on three occasions, twelve months apart. An optical motion capture system was used for three-dimensional gait analysis. Gait parameters were examined at comfortable gait speed during single-tasking, dual-tasking naming names, and naming animals. The dual-task cost for gait speed was pronounced at baseline (names 26%, animals 35%), and remained so during the study period. A significant (p < 0.05) longitudinal decline in gait speed and step length during single- and dual-tasking was observed, whereas double support time, step width and step height showed inconsistent results. Systematic visual examination of the motion capture files revealed that dual-tasking frequently resulted in gait disturbances. Three main characteristics of such disturbances were identified: Temporal disturbance, Spatial disturbance and Instability in single stance. These aberrant gait performances may affect gait stability and increase the risk of falling. Furthermore, the observed gait disturbances can contribute to understanding and explaining previous reported gait variability among individuals with AD. However, the role that dual-task testing and aberrant dual-task gait performance play in the identification of individuals with early signs of cognitive impairment and in predicting fall risk in AD remains to be studied.

  • 161.
    Cedervärn, Emilie
    et al.
    Dalarna University, School of Technology and Business Studies, Civil planning and Construction.
    Andersson, Axel
    Dalarna University, School of Technology and Business Studies, Civil planning and Construction.
    Dialogprocesser –  ett verktyg för hållbar stadsutveckling?: En studie av användandet av SymbioCity Approach i två svenska kommuner2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study is a bachelor thesis in Civil Planning and Construction at Högskolan Dalarna. Studies has shown that there’s a need for a multisectoral working process to achieve a sustainable urban development. One way to do so is through collaborative planning processes. This study examines the use of collaborative processes, based on SymbioCity Approach, in civil planning projects in two Swedish municipalities. It tries to examine what effects the process has on the municipalities planning.  The study has been conveyed through literature studies on the subject, participating observations of a collaborative planning process and 11 semi-structured interviews with participants from two planning processes.  The study has shown that collaborative planning processes based on SymbioCity Approach is a useful tool for sustainable urban development. A process like this may result in increased institutional capacity, increased multisectoral knowledge and understanding, and increased social capital.   The study also shows that important factors that may influence the results of the process are: whether a purpose has been properly articulated, if the right resources are participating and whether the level of the content of the process coincides with the purpose of the process. Furthermore, the study shows that the process needs to be properly planned to reach its full potential. It also found that different stakeholders might have different expectations and idea of what the results of the process might look like.

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  • 162.
    Ceron, Ermanno
    et al.
    Technical University of Denmark.
    Olsson, Mikael
    Dalarna University, School of Technology and Business Studies, Materials Technology.
    Bay, Niels
    Technical University of Denmark.
    Lubricant film breakdown and material pick-up in sheet forming of advanced high strength steels and stainless steels when using environmental friendly lubricants2014In: Advanced Materials Research, ISSN 1022-6680, E-ISSN 1662-8985, Vol. 966-967, p. 219-227Article in journal (Refereed)
    Abstract [en]

    Increasing focus on environmental issues in industrial production has urged sheet metal stamping companies to look for new tribo-systems in order to substitute hazardous lubricants such as chlorinated paraffin oils. The efficiency of chlorinated paraffin is due to the fact that the lubricant reacts chemically with the tool and workpiece material forming thin films, which adhere strongly to the surfaces and reduce the tendency to metal-metal contact and material pick-up. Production tests of new, environmentally benign tribo-systems are, however, costly and laboratory tests are preferred as a preliminary simulative method to investigate alternative tribo-systems. The present paper presents a case study where an industrial process, consisting of deep drawing with two subsequent re-drawings, was selected and four potential new tribo-systems were tested including different workpiece materials, i.e. AHSSs and stainless steels. The performance of the tribo-systems was analyzed in the laboratory by means of a newly developed simulative test as well as in an industrial production process. The results obtained show a good agreement between the laboratory test and the industrial production process regarding the tribological performance, i.e. tendency to material pick-up and galling, of the evaluated tribo-systems. Moreover the SEM analysis shows that different workpiece materials result in different types of material pick-up.

  • 163. Chai, J.
    et al.
    Huang, Pei
    Dalarna University, School of Technology and Business Studies, Energy Technology. City University of Hong Kong, Kowloon.
    Sun, Y.
    Differential evolution - based system design optimization for net zero energy buildings under climate change2020In: Sustainable cities and society, ISSN 2210-6707, Vol. 55, article id 102037Article in journal (Refereed)
  • 164. Chai, Jiale
    et al.
    Huang, Pei
    City University of Hong Kong.
    Sun, Yongjun
    Climate change impact on energy balance of net-zero energy buildings in typical climate regions of China2019In: E3S Web of Conferences, E-ISSN 2267-1242, Vol. 111, article id 04004Article in journal (Refereed)
  • 165. Chai, Jiale
    et al.
    Huang, Pei
    City University of Hong Kong.
    Sun, Yongjun
    Investigations of climate change impacts on net-zero energy building lifecycle performance in typical Chinese climate regions2019In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 185, p. 176-189Article in journal (Refereed)
    Abstract [en]

    Net-zero energy building (NZEB) is widely considered as a promising solution to the current energy problem. The existing NZEBs are designed using the historical weather data (e.g. typical meteorological year-TMY). Nevertheless, due to climate change, the actual weather data during a NZEB’s lifecycle may differ considerably from the historical weather data. Consequently, the designed NZEBs using the historical weather data may not achieve the desired performances in their lifecycles. Therefore, this study investigates the climate change impacts on NZEB lifecycle performance (i.e., energy balance, thermal comfort and grid interaction) in different climate regions, and also evaluates different measures' effectiveness in mitigating the associated impacts of climate change. In the study, the multi-year future weather data in different Chinese climate regions are firstly generated using the morphing method. Then, using the generated future weather data, the lifecycle performances of the NZEBs, designed using the TMY data, are assessed. Next, to mitigate the climate change impacts, different measures are adopted and their effectiveness is evaluated. The study results can improve understanding of the climate change impacts on NZEB lifecycle performance in different climate regions. They can also help select proper measures to mitigate the climate change impacts in the associated climate regions.

  • 166. Chai, Jiale
    et al.
    Huang, Pei
    City University of Hong Kong.
    Sun, Yongjun
    Life-cycle analysis of nearly zero energy buildings under uncertainty and degradation impacts for performance improvements2019In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 158, p. 2762-2767Article in journal (Refereed)
    Abstract [en]

    Sizing the nZEB systems properly is crucial for nZEBs to achieve the desired performances. The energy demand prediction uncertainties and the components’ degradation are two major factors affecting the nZEB systems sizing. The energy demand prediction has been studied by many researchers, but the impacts of degradation are still neglected in most studies. Neglecting degradation may lead to a system design that can perform as expected only in the beginning several years. This paper, therefore, proposes an uncertainty-based life-cycle performance analysis (LCPA) method to study the impacts of degradation on the nZEBs longitudinal performance. Based on the LCPA method, this study also proposes a two-stage method to enhance the nZEB system sizing. The study can enhance the designers’ understanding of the components’ degradation impacts. Case studies show that an nZEB might not achieve zero energy targets after years due to degradation. The proposed two-stage design method can effectively mitigate this problem.

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  • 167. Cheeze, David
    et al.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Haller, Y. Michel
    Hamp, Quirin
    Matuska, Tomas
    Sourek, Borivoj
    Mojic, Igor
    Persson, Tomas
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Poppi, Stefano
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Report on prototype system’s energetic  performance and financial competitiveness - Deliverable 8.3 : MacSheep - New Materials and Control for a next generation of compact combined Solar and heat pump systems with boosted energetic and exergetic performance2016Report (Other (popular science, discussion, etc.))
  • 168. Chen, X
    et al.
    Su, Y
    Aydin, D
    Bai, H
    Jarimi, H
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Raffat, S
    Experimental investigation of a polymer hollow fibre integrated liquid desiccant dehumidification system with aqueous potassium formate solution2018In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 142Article in journal (Refereed)
    Abstract [en]

    Hollow fibres have been studied as the substitute for metallic materials due to the advantages such as light weight, corrosion resistant and low cost in heat and mass transfer applications. A novel polymer hollow fibre liquid desiccant dehumidification system, in which a cross-flow hollow fibre module (fibre inside diameter=1.4mm) serves as the dehumidifier, is presented in this paper. This novel hollow fibre integrated liquid desiccant dehumidification system can be used in an air conditioning system to provide a comfortable indoor environment for hot and humid area. Compared with other conventional liquid desiccant dehumidifier, the polymer hollow fibre has a very small diameter which leads to significantly increased surface area. Moreover, the porous feature of the hollow fibre module can help to eliminate any liquid desiccant droplets carryover into the process air. As a less corrosive and more environmental friendly working fluid, aqueous potassium formate (KCOOH) solution has been selected. The dehumidification performance of the proposed system were analysed experimentally under the conditions of incoming air temperature in the range of 30°C to 45°C. The variations of dehumidification sensible and latent effectiveness, moisture removal rates were studied by varying the incoming air velocity from 0.65 m/s to 4.5m/s. With the various values of incoming air relative humidity in the range of 55% to 75% and the solution concentrations between 36% and 62%, the experimental obtained latent effectiveness are in the range of 0.25 to 0.43 and the sensible effectiveness are in the range of 0.31 to 0.52, which is in a satisfactory agreement with the empirical correlation of effectiveness-NTU in the literature.

  • 169. Chen, X.
    et al.
    Su, Y.
    Aydin, D.
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Ding, Y.
    Reay, D.
    Law, R.
    Riffat, S.
    Experimental investigations of polymer hollow fibre integrated evaporative cooling system with the fibre bundles in a spindle shape2017In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 154, p. 166-174Article in journal (Refereed)
    Abstract [en]

    Due to the advantages of light weight, corrosion resistant and low cost, hollow fibres have been studied as the substitute for metallic materials. A novel hollow fibre integrated evaporative cooling system, in which the hollow fibre module constitutes as the humidifier and the evaporative cooler, is proposed. This novel hollow fibre integrated evaporative cooling system will provide a comfortable indoor environment for hot and dry area. Moreover, the water vapour can permeate through the hollow fibre effectively, and the liquid water droplets will be prevented from mixing with the processed air. In order to avoid the flow channelling or shielding of adjacent fibres, the fibres inside each bundle were made into a spindle shape to allow maximum contact between the air stream and the fibre. The cooling performances of the proposed novel polymer hollow fibre integrated evaporative cooling system were experimentally investigated under the incoming air temperature in the range of 26 °C to 32 °C and relative humidity of 25%–35%. The effects of air velocities on the cooling effectiveness, heat and mass transfer coefficients, specific water consumption and pressure drop across the polymer hollow fibre module were analysed. Two sets of experimentally derived non-dimensional heat and mass transfer correlations were summarized, which could be favourable for the future design of polymer hollow fibre integrated evaporative cooling system.

  • 170.
    Christensen, My
    et al.
    Dalarna University, School of Technology and Business Studies, Graphic Arts Technology.
    Pihlgren, Johanna
    Dalarna University, School of Technology and Business Studies, Graphic/Arts Technology.
    Typografiska riktlinjer och textframställning för smartphones2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This research focuses on the issue of how to best structure text on a Smartphone screen. The factors involved in this research are text size, white space, text and line lengths, serif and sans serif fonts, pictures in text and contrast.  The methodology of our research is based on a normative Swedish able-bodied person, as well as on relevant literature, personal analyses, interviews with people in the trade, an online survey, and a test performed with a focus group. The results are that a text written for Smartphones is best structured with: several paragraph divisions made with blank lines, with pictures where the picture has an informational purpose, and text length based on category of subject. The picture should be placed above the body text. Longer texts should be set with a scroll-function. Contrast is of great importance on mobile phones as texts can be read properly even when set in negative. In addition, using serif or sans serif is of no importance. According to the results both serif and sans serif can be read without difficulties on a Smartphone. Text size should be slightly enlarged in relation to the default settings on the mobile device. Since word division is not supported on screen, short words are recommended when possible to prevent a highly uneven right end.

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  • 171.
    Christiansen, Marcus
    et al.
    Dalarna University, School of Technology and Business Studies, Graphic Arts Technology.
    Eriksson, Fanny
    Dalarna University, School of Technology and Business Studies, Graphic Arts Technology.
    Grafisk profil för en lunch-och cateringrestaurang2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to develop a visual identity for the lunch and

    catering restaurant Kök Nyström. The identity would then be compiled into a

    visual manual. The work was conducted using the process model “Design &

    Creation”.

    Through an interview with the client it was understood that the identity was to

    mediate the key values, “genuine crafts,” ”simplicity,” and ”quality,” and the

    catchwords “uncluttered,” “soft shapes,” and “not too much details” for the

    design work. An external analysis of local competitors’ websites was conducted

    to map out themes in their visual identities and what parts the authors found to

    be appealing and unappealing.

    Based upon the gathered information the different artefacts of the visual identity

    (logotype, typeface, color palette) was designed. These were tested on the client

    for feedback and adjusted based upon this. Afterwards the visual identity was

    tested on a focus group of professionals in the field of graphic design to clarify

    whether the visual identity was perceived to signal the company’s key values in

    a clear manner, which was found to be the case.

    The results were a coherent visual identity consisting of a new logotype,

    typefaces, and a color palette for Kök Nyström.

  • 172.
    Christoffersson, Einar
    Dalarna University, School of Humanities and Media Studies, Moving Image Production.
    Jamming with the Plot Twister: Designing virtual worlds for improvised performances2018Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Using a research through design approach, this thesis presents a first prototype of Plot Twister, a novel interactive, audiovisual interface specifically designed for solo musicians improvising alongside computers. This highly simplified and intuitive interface allows the performer to simultaneously manipulate visual and musical content using one single controller, thus enabling the other hand to play an instrument. The design is based on the concept of adaptive music used in video games, where progression of musical form and expression over time is produced through movement in virtual 3D-space. This thesis describes the design process of two interface iterations and audiovisual compositions which are first evaluated using interviews, and then through auto-ethnographic multimodal interaction analysis by stimulated recall to identify its functions and potentials in the context of improvised live performances. The results implicate different ways how the physical interface can both influence as well as enable the user to effortlessly adapt musical form and content to fit her improvised musical exploration. Both audience and performer share access to the visual interface that provides real-time visual feedback of the musical content in a “gamified” style. The technical framework strongly favours looped, continuous, gradual and non-linear progressions of computer-based media where the concept of Plot Twister potentially can be implemented in other interactive contexts in the future.

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  • 173. Chèze, David
    et al.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Betak, Jan
    Broum, Michal
    Heier, Johan
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Heinz, Andreas
    Franz, Hengel
    Hamp, Quirin
    Poppi, Stefano
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Final report on Control strategies, fault detection and on-line diagnosis in WP6 - Deliverable 6.4: MacSheep -New Materials and Control for a next generation of compact combined Solar and heat pump systems with boosted energetic and exergetic performance2015Report (Other (popular science, discussion, etc.))
    Abstract [en]

    The main objective of this work package was to investigate generic control strategies, generic fault-detection and on-line diagnosis algorithms that may apply to the developed prototypes of solar and heatpump systems within MacSheep. The results should lead toimproved reliability and/orincreased energy savings for the end-userthrough new controller features. The use of DHW consumption forecast was identified as a promising control strategy and a simple yet reasonably effective algorithm to get the water tapping behaviourof the userwas developed. Viessmannimplemented the ideas of this approach in an ICT solution for their controller to provide statistical tapping informationto the user who can then set the period when hot waterthatis expected to be used. The operationalstrategy based on DHW consumptionforecast for one hour was not implemented since the potential gains are small (~2%) and there is ahigh user discomfort risk in the case of an inaccurate forecastPrevious studies have shown that solar overheating of the building led to gas savings with solar gas combisystems. Using a similar strategy on the MacSheep reference system did not lead to significant savings, due to strong interactions between space and DHW heating and a higher share of HP operation time for DHW charging of the store, which has a lower efficiency.Another smart control strategy was investigated forvariable electricity pricesusing overheating of the building and/or the DHW volume of the store.The main conclusion of the study is that the combination of the two algorithms led to cost savings for the Austria (Graz) and France (Chambery) with both theSFH45 and SFH100 buildings.Since only the share related to user consumption varies during the day while the grid and transmission costs are usually constant, thecost savings were small, far below 1%.Among the proposed fault detection algorithms for solar and heat pump systems, detection of wrongly connected tubes in the solar collector loop was found interesting by Viesmmann and Regulus. It was implemented and tested in their respective prototype controller. Regulus also implemented the detection of wrong order phase connections in its heat pump prototype as well as threshold tests on abnormal temperature and pressure evolution.

  • 174. Chèze, David
    et al.
    Papillon, Philippe
    Leconte, Antoine
    Persson, Tomas
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Haller, Michel Y.
    Haberl, Robert
    Towards an harmonized whole system test method for combined renewable heating systems for houses2014Conference paper (Other academic)
    Abstract [en]

    The objective of this work is the development of harmonized efficiency test methods for combined renewable heating systems for houses, using a hardware-in-the-loop approach. An overview of the principles of the existing whole system test methods used by 3 research institutes involved in the project (MacSheep 2012) is given. Main objectives are realistic dynamic test sequence elaboration for solar and heat pump systems and comparison of results from tests achieved in different institutes. In order to reach these objectives, the first phase of the work aimed to harmonize the boundary conditions that comprise both the physical boundaries of the tested system as well as the climate and heat load definition, and this is presented in the first part of the article. The second part presents two methodologies to elaborate 12-days and 6-days whole system test sequences, validation results for solar and air source heat pump systems (SHP) and a methodology for achieving equal amount of space heat supplied by the tested system while at the same time providing a realistic response of the heat distribution system.

  • 175.
    Cialani, Catia
    et al.
    Dalarna University, School of Technology and Business Studies, Economics.
    Giannantoni, Corrado
    ENEA (National agency for new technologies, Energy and sustainable economic development)).
    A new approach to future energy strategies based on GDP2000In: 2nd International Workshop "Advances in Energy Studies, Exploring Supplies, Constriants, and Strategies" / [ed] Prof Sergio Ulgiati, SGE Editoriali, Padova, 2000, p. 397-408Conference paper (Refereed)
  • 176. Ciccarese, Lorenzo
    et al.
    Mattsson, Anders
    Dalarna University, School of Technology and Business Studies, Forest and Wood Technology.
    Pettenella, Davide
    Ecosystem services from forest restoration: thinking ahead2012In: New forests, ISSN 0169-4286, E-ISSN 1573-5095, Vol. 43, no 5-6, p. 543-560Article in journal (Refereed)
    Abstract [en]

    Global deforestation and forest degradation have led to massive loss of biodiversity and decline of ecosystem services. Against this prospect, it is important not only to protect, but also to restore forest ecosystems. The paper analyzes the current and future role of the restoration of forests and degraded lands starting with the definition of various techniques, scales and objectives of forest restoration. Three key motivations for and targets of forest restoration are then discussed: forest biodiversity protection, biomass production, climate change mitigation and adaptation. The paper also briefly discusses three tools of increasing relevance for supporting forest restoration policies: the development of forest nursery techniques and the improvement of quality of forest reproductive material, the use of standard and certification tools, and financing of restoration investments, including projects aimed at reducing emissions from deforestation and forest degradation. We conclude by making some final remarks on the future challenges of forest restoration policies.

  • 177.
    Cubillas Camou, Elsa
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Performance Analysis on Photovoltaic Plant in Norway2018Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study is to analyze the performance of the biggest PV system located in Oslo, Norway. The PV system has a capacity of 130 kW, it started operations in 2014 and it is located on the rooftop of a nursing house managed by the municipality. The analysis was done by making four different comparisons that lead to have a more detailed overview. The comparisons were from the energy production from different years, months and days; the performance ratio from different subsystems; the modeled energy output vs the actual energy output and lastly a relative degradation from different subsystems.

    The thesis was conducted in Kjeller, Norway at the Institute for Energy Technology facilities. Data was collected from two different monitoring systems, the first was from an onsite weather station and the second was from the energy production monitoring system. After collecting all the data, the production comparison from different years, days and months was performed. A performance ratio analysis was done in order to know how well the PV system was performing. The software HelioScope was used to simulate a model of the PV system and the results of the simulation were compared to the real energy output. A degradation analysis without irradiance data proposed by the National Renewable Energy Laboratory was implemented to compare the degradation rate between different subsystems.

    The production analysis comparison within subsystems demonstrates that some identical subsystems produce more energy than others. For the performance ratio analysis, the results showed that the PV system has a good performance ratio despite of the shading some PV modules receive. The simulation of the model in HelioScope showed some discrepancies for the winter months while for summer months it was more accurate. Finally, the degradation analysis was not possible to demonstrate actual results, but the methodology was implemented.

  • 178.
    Córdoba Candela, Jose
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Prefeasibility Study of a Central Solar Heating Plant with Seasonal Storage in Astana2015Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The feasibility of a Central solar heating plant with seasonal storage (CSHPSS) in a new district in Astana was evaluated. A total usable footprint of 481271 m2 of low energy (passivhaus standards) multi storey apartment blocks and single family houses (15000 expected inhabitants) was studied.

    Astana is a very cold climate, with heating degree days (below 18 °C) of 5724 °C.day/year. However the solar radiation is higher than in northern Europe (where most CSHPSS are located). Space heating demand, using passivhaus standards, would be 7.2 GWh/y, DHW demand calculated was 11 GWh/y and transmission losses 2.41 GWh/y.

    Astana’s DH network was studied in order to analyze the integration of this solar thermal system within the city network. Nevertheless due to its typology (open system) and its temperature regime a newly built DH within the existing network is chosen, a secondary 60/30 °C network is considered to be appropriate. Previous plants and technologies used in central plants were reviewed in order to select the most appropriate ones.

    In the simulation, collector areas between 1.4 and 2.5 m2 per MWh heat demand and water storage volumes between 1.2 and 4.0 m3 per m2 collector area satisfy between 41 and 81 per cent of the total heat demand by solar thermal heat. Levelized cost of energy (LCOE) increases from 0.099 €/kWh to 0.107 €/KWh when increasing the solar fraction. Two systems were selected as optimum (from LCOE point of view) that gave solar fractions of at least 50 % and 80 %.

    In order to calculate feed-in tariff, Net Present Value (NPV) and Payback Time (PBT), local economic figures were chosen considering different financial considerations resulting in a discount rate of 12% and inflation of 7%. Since the heat tariff for solar thermal is not defined by law, this tariff was calculated for an expected internal rate of return of 28%. For SF=50% the investment would have a feed-in tariff of 0.184 €/kWh, a PBT=8.2 years and NPV=9.92 M€. For SF=80% the investment would have a feed-in tariff of 0.191 €/kWh, a PBT=7.75 years and NPV=16.7 M€.

  • 179.
    d’ Souza, David
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Experimental Characterisation and Modelling of a Membrane Distillation Module Coupled to aFlat Plate Solar Collector Field2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    An experimental characterisation of a pre-commercial spiral wound permeate gap membrane distillation module was carried out to test its performance at different operating conditions for the purpose of seawater desalination. The experimental setup consisted of a flat plate solar collector field indirectly coupled to the permeate gap membrane distillation module via an inertia tank. The operating parameters varied were the condenser inlet temperature (from 20 °C to 30 °C), evaporator inlet temperature (from 60 °C to 80 °C) and seawater feed flow rate (from 200 l/h to 400 l/h). Within this operational boundary, it was found that the maximum permeate/distillate flux was 4.135 l/(h∙m2) which equates to a distillate production/flow rate of close to 21.3 l/h. The maximum potential distillate production rate is expected to be significantly higher than this value though as the maximum manufacturer specified feed flow rate is 700 l/h and the maximum evaporator inlet temperature is rated at 90 °C. Both these parameters are positively related to the distillate production rate. The minimum specific thermal energy consumption was found to be 180 kWh/m3.

    A mathematical model of the overall system was developed, and experimentally validated, to mathematically describe the coupling of the membrane distillation module with a solar collector field. The effectiveness of internal heat recovery of the membrane distillation module was found to be an accurate and simple tool to evaluate the thermal energy demand of the distillation process at a given set of operation parameters. The mathematical model was used to further investigate the experimental findings and provide insights into the operational dynamics of the membrane distillation module. It was also used to determine some external conditions required for steady state operation, at a given distillation operating point, such as the minimum solar irradiation required for operation and the auxiliary cooling required in the solar collector loop for maintaining steady state conditions.

    Finally, general guidelines are provided toward better operational practices to improve the coupling of a solar thermal collector unit/field with a membrane distillation system using a storage tank or inertia tank.

     

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  • 180.
    Dahlblom, Linus
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Utveckling av infästningsplattor för montering av solpaneler på tätskiktstak2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Solar panels are becoming more and more common. Unfortunately, there are currently no solutions adapted to secure the panels on membrane roofs. Instead, they are attached with methods that are meant for personal safety, which are oversized for the purpose. In this work a mounting plate that is adequately sized for mounting solar panels is developed. This is done using a product development process that is designed to define the loads on the panels and from there develop a solution which is shaped and sized for the purpose. The result is a product that withstands the loads with a good margin to a considerably lower price than the original solutions.

  • 181.
    Dalenbäck, Jan-Olov
    et al.
    Svensk Solenergi.
    Ollas, Patrik
    SP Energiteknik.
    Persson, Tomas
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Biobränsle och solvärme för 100% förnybar värmeförsörjning: Projekt nr 30688-2 - Biobränsle och solvärme2015Report (Other academic)
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  • 182.
    Dalin Nilsson, Anette
    Dalarna University, School of Technology and Business Studies, Materials Technology.
    Jämförelse av restaustenit i ett härdat verktygsstål för varmarbetsapplikationer: martensitisk och baintisk mikrostruktur2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been conducted at Uddeholms AB in Hagfors. Samples and measurements have been made on a tool steel; Uddeholm Dievar. Dievar is a hot work tool steel which is best suited for large tools.

    Retained austenite is always found in hardened high alloyed steel. It is said to decompose into cementite and ferrite during tempering. The decomposition product affects the impact toughness in a negative way. An impaired impact toughness increases the risk for cracking. Using the correct temperature during austenitizing improves the steel properties.

    The sample that have been used varies in austenitizing and in cooling rate. There is a fast cooling and one slow cooling rate which corresponds to cooling of the core in a large tool. A comparison have been made on the microstructure of the different samples, this has been conducted in a SEM. The mapping of phases has also been made with the use of a SEM (Scanning Electron Microscope) and with an ESBD-detector (Electron Backscatter Diffraction). The values on impact toughness have been relative to the content of retained austenite. This report shows how the austenitizing and cooling rate affect the contents of retained austenite and how the content influences the impact toughness.

    The microstructure of the samples varies depending on austenitizing temperature. Some conclusions that can be made from this thesis are that the content of retained austenite increase with the lowering of the temperature during austenitizing when it comes to bainitic micro structure. In the martensitic sample the retained austenite decreases with the austenitizing temperature. During the assembly of the impact toughness values it showed that the samples with the highest content of retained austenite prior tempering were the ones with the lowest value when the test was conducted.

  • 183.
    Daniels, Jonas
    Dalarna University, School of Technology and Business Studies, Graphic/Arts Technology.
    Grafisk profilering till Kitty Grafisk Form samt teoretisk tillämpning av kulörer2005Independent thesis Basic level (degree of Bachelor)Student thesis
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  • 184.
    Daniels, Maria
    Dalarna University, School of Technology and Business Studies, Occupational science. Dalarna University, School of Health and Social Studies.
    Inspirationsbenchmarking för förbättrad verksamhet för ABB Components i Ludvika2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 185.
    Danielsson, Christoffer
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Hansson, Christopher
    Dalarna University, School of Technology and Business Studies, Construction.
    Planindikatorer som utvärderingsverktyg för hållbar fysisk planering: En konsekvensbedömning på detaljplanenivå2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The urbanization that has occurred in the last century results in an increasing awareness of urban planning and assessment tools are increasingly used to demonstrate that development in the direction of sustainable occurs.

    The purpose of this study is to produce indicators and analyze how the municipality development plans for the station area in Borlänge meet the national-, regional- and local objectives in terms of sustainable urban planning. The method applied in the development of indicators is based on Boverkets and Naturvårdsverkets model that was developed in conjunction with the SAMS-project. Applying this method has resulted in eleven indicators that have been applied to the present situation and the development plans in which the result shows that any major change to the assessment ladder has not occurred.

    As a result of some municipal goals beeing vaguely designed, the difficulty in meeting them increases. This creates a difficulty in applying the assessment tools in the form of indicators that can guide planning in the right direction. The development plans extent is not enough for the municipal goals to be met. The produced planning indicators can be the basis for a dialogue with the municipality in order to sharpen the objectives and generate a better goal achievement.

  • 186.
    Danielsson, Helena
    et al.
    Dalarna University, School of Humanities and Media Studies, Art Education.
    Taflin, Eva
    Dalarna University, School of Education, Health and Social Studies, Mathematics Education.
    Rapport från projektet Multimodala uppgifter och bedömning i matematik: Video och kollaborativa samtal som metod vid lärares bedömning av elevers matematiska kunskaper2015Report (Other academic)
    Abstract [en]

    This research will discuss some experiences from a four year school research study. It was conducted in cooperation with teachers from four municipalities in Dalarna. The aim of the research was to examine teachers´ professional development when they participated in collaborative discussions based on video recordings and video edited material from specific lessons in their own practice. The study had two foci one was to investigate methods and tools that teachers can use to develop their ability to assess their students while working on multimodal tasks. The other was to examine how video can be used by teachers wanting to obtain knowledge about assessing students. The study is based on several theories about when teachers collaborate to create new knowledge. The first is the design theoretical approach – where visual ethnography and a semiotic approach contribute to problematize the use and mixture of different modes. A basic assumption of the framework here is that meanings are made and communicated in mathematics through a wide range of semiotic modes. By using video as an essential tool in the research the framework theories concerning visual ethnography, video documentation and individuals as reflective practitioners were also needed. The findings can be divided into the following themes: the use of tasks for assessment, collaborative discussion, equipment, ethical dilemmas. Collaborative discussions were evaluated as a meaningful way of sharing knowledge. The use of video recordings in association with these discussions raised important ethical issues. Working with the assessment framework was of great interest to the teachers but it took a lot of time from their ordinary work. In this way the project highlighted more general aspects of school development. The research also concerns teachers´ use of collaborative discussions in assessment work, multimodal tasks in mathematics and video as a research tool in general.

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  • 187.
    Daroudi, Parham
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Simulation of an energy efficient single-family house in the area of Smedjebacken to meet Miljöbyggnad’s Gold House energy category requirements2018Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since the building construction area is accounted for high share of energy usage (36 %) in

    Europe, there is high demand to pay attention to this area accurately. Sweden which is one

    of the pioneer countries in terms of building energy efficiency plans to reduce this value to

    50 % by 2050. To reduce this value there is a need to define a mandatory guideline for

    builders by the government. So national board of housing, building and planning (Boverket)

    were given responsibility to define these regulations for builders and house owners. Parallel

    with that Swedish green building council developed a certification considering the buildin

    g’s

    energy demand, indoor air climate and environmental impact of building called

    Miljöbyggnad. While all the existing and new buildings following Boverket’s regulations

    meet this certification’s lowest limitations, some ambitious

    builders tend to fulfil its highest

    level of limitations called Gold level.

    This study aimed to design a house in the area of Smedjebacken to meet Miljö

    byggnad’s

    gold house’s energy category requirements. To meet the mentioned requirements several

    parametric studies regarding insulation thickness, windows assembly, heating and ventilation

    system are done via simulation software called TRNSYS. The result of testing several

    models show that although windows assembly does not affect this building

    ’s energy demand

    very much, other parameters such as insulation

    ’s thickness and type of heating system have

    a key role.

    In addition, a parametric study regarding the impact of thermal mass on the building energy

    demand is performed. The result shows that the effect of removed massive wood is

    compensated by replaced additional mineral wool insulation.

    In conclusion it is concluded that a single family house located in a cold climate like

    Smedjebacken using

    district heating cannot meet Miljöbyggnad’s gold level criteria without

    help of heat recovery ventilation. Furthermore, building with ground source heat pump as

    its

    heating system can meet Miljöbyggnad’s principals easier than those having district

    heating. In this case building with 200 mm insulation thickness even with exhaust air

    ventilation meets certification principals easily.

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  • 188.
    Darth, David
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Värmehantering - Datorstödd dimensionering av kapsling för batteriladdare2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis-work, the possibility of integrating a heat sink in the encapsulation of a batterycharger has been investigated. To manage the thermal load, a plate-finned heat sink has been dimensioned. Two design concepts have been developed, with two different heat sinks integrated in the design. The concepts thermal performance has been simulated in Solidworks Flow Simulation to identify surface-temperatures, component-cooling, flow conditions and radiation. The results from the calculations and the simulations shows that both of the concepts, at an ambient temperature of 30ᵒC, performs a sufficient heat flux to keep the internal components under 93ᵒC. The battery-charger’s encapsulation temperature would not exceed 54ᵒC under these conditions. For further development, a concept with the heat sink covered by a “lid” has been recommended.

  • 189. Davami, Erfan
    et al.
    Fleyeh, Hasan
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Classification with NormalBoost2011In: Journal of Intelligent Systems, ISSN 0334-1860, Vol. 20, no 2, p. 187-208Article in journal (Refereed)
    Abstract [en]

    This paper presents a new boosting algorithm called NormalBoost which is capable of classifying a multi-dimensional binary class dataset. It adaptively combines several weak classifiers to form a strong classifier. Unlike many boosting algorithms which have high computation and memory complexities, NormalBoost is capable of classification with low complexity. Since NormalBoost assumes the dataset to be continuous, it is also noise resistant because it only deals with the means and standard deviations of each dimension. Experiments conducted to evaluate its performance shows that NormalBoost performs almost the same as AdaBoost in the classification rate. However, NormalBoost performs 189 times faster than AdaBoost and employs a very little amount of memory when a dataset of 2 million samples with 50 dimensions is invoked.

  • 190.
    de Fatima Dias, Jane
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Reuse of Construction Materials2018Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The building and construction sectors are one of the main contributors to the socio-economic development of a country. Globally, these sectors generate around 5% to 10% of national employment and around 5% to 15% of a country's gross domestic product during construction, use and demolition. On the other hand, the sectors consume around 40% of world primary energy, use 30% of raw materials, generate 25% of solid waste, consume 25% of water, and use 12% of land. Furthermore, the sectors account for up to 40% of greenhouse gas (GHG) emissions, mainly from energy use during the life cycle of buildings.

    This study aims to assess the potential environmental benefits of reusing concrete and ceramic roof tile within the Swedish context in terms of their CO2 emission. Methodology used was a comparative LCA was to quantify the emissions. In order to calculate LCA, OpenLCA 1.7.0 software was used and to evaluate the emissions, LCIA method selected was ReCiPe, midpoint, Hierarchist model, climate change category expressed in GWP 100 years (in kg CO2eq). The FU of the study was a square meter of roof covering for a period of 40 years with potential to extent up to 80 years. A square meter of concrete roof tile weight 40 kg while ceramic 30 kg.

    The environment impact evaluation considered three product system, single use (cradle to grave), single use covering (cradle to user) and single reuse (user to cradle) within 40 years lifespan. In order to compare LCA of the roof tiles, two scenarios were created, Scenario 1 concrete RT in single use and single reuse whilst Scenario 2 evaluates ceramic RT. The outcomes of both scenarios were communicated through a model single family house. Dalarna’s Villa is located in Dalarna region in Sweden and a storage facility Ta Till Våra was to validate the benefits of reused materials.

    Comparative LCA revealed that concrete RT in single use released almost 80% more CO2 emissions than ceramic RT and generated 25% more disposable material by weight. The CO2 released by the single use vs. single reuse concrete RT showed higher emissions in the production of the concrete RT than the single reuse, the same occur with ceramic RT. The reuse of the tiles on the same site had an insignificant impact on the environment in both materials. The comparison shows that reuse reduces associated emissions by about 80% in both cases, reusing concrete is more beneficial, as emissions are reduced by 9.95 kg/m2 as opposed to 2.32 kg/m2 at the ceramics. This study reveals the benefit of reusing concrete and ceramic roof tile. In addition, the advantage of building a storage facility to reuse the disposable building materials, reducing the roofing materials ending at the landfill after 40 years. Furthermore, it demonstrated the reduction of CO2 emissions associated with the embodied energy.

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  • 191.
    Deeks, Christopher
    Dalarna University, School of Humanities and Media Studies, Moving Image Production.
    Pang! Från auteurens symboler till betraktarens känslor: En analys av Jesse James sista dag i livet i filmen The assassination of Jesse James by the coward Robert Ford2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den här uppsatsen syftar till att skapa en större förståelse för vad en spelfilm förmedlar till

    betraktaren, utan att betraktaren aktivt söker en betydelse när denne ser på den. För att

    undersöka detta kommer en scen ur filmen The Assassination of Jesse James by the coward

    Robert Ford att analyseras. Uppsatsen kommer att studera semiotiska- och sociosemiotiska

    tecken samt ljud och musik för att undersöka hur dessa komponenter tillsammans bygger upp

    till en stark känslomässig upplevelse för betraktaren. Resultatet av undersökningen visar att

    tecken, som har starka betydelser för människan, används för att skapa makt och distans och

    förtydliga vem som känner vad, vad de känner samt även att ljud och musik hjälper till att

    lyfta dessa känslor till en starkare nivå.

  • 192.
    Dellfjord, Veronica
    Dalarna University, School of Technology and Business Studies, Construction.
    Kunskap hos privatpersoner om fukt på kallvind2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    It is common that homeowners are recommended to add an insulation layer on the attic to lower building heating energy, however many do not realize the problem with complementary insulation compared to what the building and the building shell is adapted for. The lack of knowledge of the homeowners, can result in that they accidentally fill the longitudinal ventilation slits on the cold roof that is there to maintain the natural ventilation and prevent air from drying out any moisture.

    The aim is to find thus out:

    • How much knowledge do the homeowners have about the risk of moisture problems in the cold roof, and how to prevent future moisture damage in the best way, depending on the design of the roof?

    • Is there a risk of moisture problems for the objects studied, based on moisture measurements and high moisture content?

    The method chosen for the study was semi-structured interviews, containing sixteen questions, with homeowners and measurements of relative humidity of air and wood and the moisture content in the wood. The study was limited to the spring of 2016 and to four homeowners.

    It turned out to differ little among the interviewers on how much knowledge they had about moisture in cold roofs and how much knowledge they possess today. Some had enough knowledge to prevent moisture damage while others needed more information. Several felt that the insurance company is where they have to acquire information from, preferably in the form of a leaflet with short questions, sent out annually.

    The measurements proved to give good results with little risk of moisture damage to the cold roofs. There were no high moisture content in neither truss nor inside roof.

  • 193. Dermentzis, G.
    et al.
    Ochs, F.
    Gustafsson, M.
    Calabrese, T.
    Siegele, D.
    Feist, W.
    Dipasquale, C.
    Fedrizzi, R.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    A comprehensive evaluation of a monthly-based energy auditing tool through dynamic simulations, and monitoring in a renovation case study2019In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 183, p. 713-726Article in journal (Refereed)
    Abstract [en]

    An energy auditing tool (PHPP) was evaluated against a dynamic simulation tool (TRNSYS) and used for the assessment of energy conservation measures in a demo case study. The comprehensive comparison of useful heating and cooling demands and loads included three building types (single-, multi-family house, and office), three building energy levels (before renovation and after renovation with a heating demand of 45 and 25 kWh/(m²·a)) and seven European climates. Dynamic simulation results proved PHPP (monthly energy balance) to be able to calculate heating demand and energy savings with good precision and cooling demand with acceptable precision compared to detailed numerical models (TRNSYS). The average deviation between the tools was 8% for heating and 15% for cooling (considering climates with a relevant cooling load only). The higher the thermal envelope quality was, i.e. in case of good energy standards and in cold climates, the better was the agreement. Furthermore, it was confirmed that PHPP slightly overestimates the heating and cooling loads by intention for system design. The renovation design of a real multi-family house was executed using PHPP as energy auditing tool. Several calculation stages were performed for (a) baseline, (b) design phase, and (c) verification with monitoring in order to calculate the corresponding heating demand. The PHPP model was calibrated twice, before and after the renovation. The necessity for tool calibration, especially for the baseline, was highlighted increasing the confidence with respect to a number of boundary conditions. In this study, PHPP was tested as an energy auditing tool aiming to be a versatile and less error-prone alternative to more complex simulation tools, which require much more expert knowledge and training. 

  • 194.
    Dermentzis, Georgios
    et al.
    Univeristy of Innsbruck.
    Gustafsson, Marcus
    Dalarna University, School of Technology and Business Studies, Energy Technology. KTH.
    Ochs, Fabian
    Univeristy of Innsbruck.
    Holmberg, Sture
    KTH.
    Feist, Wolfgang
    Passivhaus Institut.
    Calabrese, Toni
    University of Innsbruck.
    Oberrauch, Philipp
    University of Innsbruck.
    Evaluation of a versatile energy auditing tool2016Conference paper (Refereed)
    Abstract [en]

    Energy auditing can be an important contribution for identification and assessment of energy conservation measures (ECMs) in buildings. Numerous tools and software have been developed, with varying degree of precision and complexity and different areas of use.

     

    This paper evaluates PHPP as a versatile, easy-to-use energy auditing tool and gives examples of how it has been compared to a dynamic simulation tool, within the EU-project iNSPiRe. PHPP is a monthly balance energy calculation tool based on EN13790. It is intended for assisting the design of Passive Houses and energy renovation projects and as guidance in the choice of appropriate ECMs.

     

    PHPP was compared against the transient simulation software TRNSYS for a single family house and a multi-family house. It should be mentioned that dynamic building simulations might strongly depend on the model assumptions and simplifications compared to reality, such as ideal heating or real heat emission system. Setting common boundary conditions for both PHPP and TRNSYS, the ideal heating and cooling loads and demands were compared on monthly and annual basis for seven European locations and buildings with different floor area, S/V ratio, U-values and glazed area of the external walls.

     

    The results show that PHPP can be used to assess the heating demand of single-zone buildings and the reduction of heating demand with ECMs with good precision. The estimation of cooling demand is also acceptable if an appropriate shading factor is applied in PHPP. In general, PHPP intentionally overestimates heating and cooling loads, to be on the safe side for system sizing. Overall, the agreement with TRNSYS is better in cases with higher quality of the envelope as in cold climates and for good energy standards. As an energy auditing tool intended for pre-design it is a good, versatile and easy-to-use alternative to more complex simulation tools.

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  • 195.
    Dimtsu Tamene, Hailu
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Solar Mini-grid Model Validation for Rural Electrification2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis was aimed at validating an Excel tool developed by Energicity Company. In addition, to study a commercial software that can be used to design a solar mini-grid system for the company.

    A 9.9 kW solar mini-grid in Bekwai, Ghana was used as a case study. Weather data from Meteonorm and component specification was used as input parameter for the simulation works.

    HOMER pro and PVsyst commercial software were selected to validate the Excel tool. Each software was also explained in detail.

    The validation was done by comparing input parameters and simulation results of the Excel tool with the selected commercial software. The process was divided into two main parts. The first part was, comparing the mathematical model, and the PV array electricity production of the software used as an input to the Excel tool, which was SAM, with HOMER pro and PVsyst. The second part was comparing the final simulation result of both tools, including the Excel tool.

    The comparison result shows that the difference in the mathematical model for the diffuse irradiation in each software leads to a difference in the electricity production at the PV array output. Even though the difference is not significant for a small scale mini-grid system, the difference can cause a wrong estimation for critical loads, where a higher percentage of availability is required.

    The DC losses at the PV array has a notable impact on estimating the electricity production. PVsyst considers more loss parameters than SAM and HOMER pro. As a result, the simulation result of the PVsyst shows lower electricity production at the output of the PV array compared to the others. This indicates as PVsyst is a more conservative software model.

    The loss in the battery has another significant impact on estimating the energy delivered to the load. The battery model for each tool was different. The Excel tool uses higher battery loss percentage. Due to this, the energy served to the load by the Excel tool was lower than HOMER pro and SAM. HOMER pro’s estimation of the battery loss was almost equal to the Excel tool. The battery loss estimated by PVsyst was lower than all models. However, there were uncertainties in the input parameters of the battery, because of most of the parameters provided by the battery manufacturer was not compatible with the input parameters required by PVsyst.

  • 196. Dipasquale, Chiara
    et al.
    Fedrizzi, Roberto
    Bellini, Alessandro
    Gustafsson, Marcus
    Ochs, Fabian
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Database of energy, environmental and economic indicators of renovation packages for European residential buildings2019In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 203, article id 109427Article in journal (Refereed)
    Abstract [en]

    Increasing the energy efficiency with a vast impact in the residential building stock requires retrofit solutions that can be exploited with respect to a wide range of different building typologies and climates. Several tools and methodologies are nowadays available both for the assessment of building demands and for the individuation of optimum retrofit solutions. However, they are usually either too complex to be adopted by professionals or, on the contrary, oversimplified to account for the full complexity of a deep envelope and HVAC system retrofit. In this context, this paper describes a methodology developed to generate reliable information on retrofit solutions for typical buildings in different climatic conditions. Detailed numerical models are used to simulate a number of combinations of envelope and HVAC systems retrofit measures and renewable energy integration. Energy performance results are gathered in a database that allows comparing solutions, spanning over a range of more than 250,000 combinations of building types, age of construction, climates, envelope performance levels and HVAC systems configurations. Economic feasibility is also derived for each of the combinations. In this way, the accurateness of a detailed and validated calculation is made available to assist during the decision making process, with minimum computational effort being required by professionals: the variety and density of evaluated combinations allows to easily assess the performance of a specific case by interpolating among instances previously assessed. The applicability of the results to different climates and similar building typologies is verified by a comparison of the database results with a specific case dynamic simulation.

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  • 197.
    Diyad Elmi, Mohamed
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Manoharan, Lavaraj
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Optimal Grid Connected Inverter Sizing for Different Climatic Zones2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Grid connected inverter requires accurate and appropriate sizing which depends on the temperature, inverter operating efficiency, performance ratio, annual system yield and solar radiation characteristics. The aim of this study was to design and size for optimum sizing factor for grid connected inverter. The main component to be considered in any photovoltaic grid connected system is the inverter since the output depends on the inverter sizing ratio, therefore optimal sizing factor was designed by considering factors that affects inverter sizing such as temperature, irradiance and the location. Large and small systems of 50 kW and 5 kW respectively were considered to determine grid connected inverter sizing factors for different climates in Kenya, Sweden, and India using PVsyst simulation. Two different inverter brands of SMA and ABB with 20 kW and 25 kW rating for large system and 4.6 kW, 4 kW inverters for small system.

    PVsyst simulation result showed that different locations with different orientation angles, the optimum sizing varies hence affects the annual performance of the system. Photovoltaic system inverters are sized based on the rated power of the installed system and this can be achieved when the inverter size is either almost matching or not.

    In this case the study presents the optimal sizing factor for grid connected inverter for Mandera in Kenya, Norrköping in Sweden and Kerala in India. The determination was done through the use of designing, assessing and analyzing of the relationship between the sizing factor with performance ratio, operational efficiency and annual hourly energy yield. The unique weather profile in Kerala and in Mandera favors the adoption of solar energy technology in the location. Solar radiation for one year was used as a baseline input and the result reveals that Mandera receives yearly radiation of 2.1 MWh/m² while Kerala and Norrköping receives 2 MWh/m² and 1.1 MWh/m² respectively.

    Design simulation using PVsyst tool made it possible for the determination of the optimal sizing factor for the grid connected system. Considerations such as the losses and the variations within the specific location was done and a graph showing the relationship between the sizing factor in relation to the operational inverter efficiency as well as energy yield and performance ratio was later on compared to see the behavior of the sizing factor.

    The study concludes that operational efficiency, performance ratio and energy yield affects the array optimum sizing ratio. For the three locations, inverters (SMA and ABB) shows different variations because optimal sizing ratio depends on the location and irradiation. The results reveal that Mandera has an optimal grid connected inverter sizing of the range from 1.1 to 1.4 while in Kerala it has from 1.2 to 1.4 and Norrköping has the range from 1.1 to 1.3. Optimal sizing of grid connected inverters depends on the energy yield and the location therefore the inverter mismatch voltage and its rating values have to be considered while determining the optimal sizing factor. The 25 kW inverters in all the locations had better efficiency and sizing factor and this proves that sizing the photovoltaic inverter will give better performance and efficiency.

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  • 198.
    Djärv, Jesper
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Israelsson, Daniel
    Dalarna University, School of Technology and Business Studies, Construction.
    Uttorkning i betong: En jämförelse av uttorkningstider mellan bascement och byggcement.2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In construction projects, moisture problems have been discovered in concrete slabs where plastic mats have been released from the substrate. One of the problems reported in the media is the change from Portland cement to fly ash cement. Fly ash cement is a cement with 14% fly ash mixed with portland clinker. The reason that cement manufacturers use fly ash, which is a residual product from powder-fired coal power plants, is that it reduces the amount of portland clinkers that release large amounts of carbon dioxide during production.

    Cement is the concrete binder and when fly ashes are used, less amount of water is bound in the concrete's hydration process. To investigate the difference in dehydration found in concrete with fly ash cement and Portland cement, two concrete samples were obtained with the same concrete recipe and VCT numbers, but with different cement types. These concrete samples were stored in a heated local with low relative humidity. Moisture measurements were carried out according to the current regulations. These results were compared with the moisture predictions from TorkaS and BI Dry, which are the most commonly used moisture calculation programs. At the same time, various actors from the construction industry were interviewed to investigate how they perceived the problem of dehydration in concrete.

    The moisture measurements showed no significant difference between concrete with base cement and building cement. When compared with the forecasted values from the moisture calculation programs, it was found that the Dry values were very close to the measured moisture values, while BI Dry's values were well below the measured values. The interviews revealed that the construction industry has many questions about dehydration in concrete. On the other hand, there are difficulties in determining what is the basis for the problems. If there is a change from the portland cement to the fly ash cement, or the handling of the concrete at an early stage after the casting affects. However, if the moisture issue is taken up early in the construction process, it is possible to save both time and money. The construction industry needs to be educated how the process of desiccation works to increase understanding of the problem.

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  • 199.
    Dominic, Chris
    et al.
    Högskolan i Gävle.
    Olsmats, Carl
    Dalarna University, School of Technology and Business Studies, Industrial Engineering and Management.
    Four-dimensional concurrent engineering - an extended theoretical framework integrating packaging2019Conference paper (Other academic)
    Abstract [en]

    This paper takes on the challenge to integrate packaging in a concept of four-dimensional concurrent engineering (4DCE). The purpose is to explore a conceptual model and empirically evaluate the specific performance of packaging in interrelation with product and processes in the Supply Chain (SC). The objectives are to better understand the concepts of packaging logistics and logistics management in the SC. The conceptual model 4DCE is developed based on the three-dimensional concurrent engineering theories.The tool Packaging Scorecard is applied to evaluate the concurrent performance of packaging throughout the SC. The packaging system involves many actors that are integrated into the 4DCE framework with focus on interaction of SC and logistics in relation to packaging and product, with the overall aim to operate as effectively and efficiently as possible. In order to explore the potential of the 4DCE framework, empirical verification and testing of the concept has been carried out. The process has been done through multiple in-depth, action-oriented case studies in three different industries on the Swedish market. The case studies covered holistic aspects on the packaging system.The concept 4DCE contributes to packaging logistics theory by providing a framework for assessment incorporating complex and dynamic interactions between product, packaging, logistics and SC. Furthermore, the holistic packaging development concept is ensured by increasing knowledge of the packaging system and how it interacts with actors and performs to fulfil requirements along the SC. The 4DCE provides valuable data for packaging development processes in the cases, however there is a need for broader studies in different industries.

  • 200.
    Donnadieu, Patricia
    et al.
    Laboratoire SIMaP, CNRS—Université de Grenoble, F-38402 Saint Martin d’Hères, France.
    Pohlmann, Carsten
    IFW Dresden, Institut für Komplexe Materialien, Postfach 27 01 16, D-01171 Dresden, Germany; .
    Scudino, Sergio
    IFW Dresden, Institut für Komplexe Materialien, Postfach 27 01 16, D-01171 Dresden, Germany.
    Blandin, Jean-Jacques
    Laboratoire SIMaP, CNRS—Université de Grenoble, F-38402 Saint Martin d’Hères, France.
    Surreddi, Kumar Babu
    IFW Dresden, Institut für Komplexe Materialien; Chalmers University of Technology, Gothenburg.
    Eckert, Jürgen
    IFW Dresden, Institut für Komplexe Materialien, Postfach 27 01 16, D-01171 Dresden, Germany.
    Deformation at ambient and high temperature of in situ Laves phases-ferrite composites2014In: Science and Technology of Advanced Materials, ISSN 1468-6996, E-ISSN 1878-5514, Vol. 15, no 3Article in journal (Refereed)
    Abstract [en]

    The mechanical behavior of a Fe80Zr10Cr10 alloy has been studied at ambient and high temperature. This Fe80Zr10Cr10 alloy, whoose microstructure is formed by alternate lamellae of Laves phase and ferrite, constitutes a very simple example of an in situ CMA phase composite. The role of the Laves phase type was investigated in a previous study while the present work focuses on the influence of the microstructure length scale owing to a series of alloys cast at different cooling rates that display microstructures with Laves phase lamellae width ranging from ∼50 nm to ∼150 nm. Room temperature compression tests have revealed a very high strength (up to 2 GPa) combined with a very high ductility (up to 35%). Both strength and ductility increase with reduction of the lamella width. High temperature compression tests have shown that a high strength (900 MPa) is maintained up to 873 K. Microstructural study of the deformed samples suggests that the confinement of dislocations in the ferrite lamellae is responsible for strengthening at both ambient and high temperature. The microstructure scale in addition to CMA phase structural features stands then as a key parameter for optimization of mechanical properties of CMA in situ composites.

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