Change search
Refine search result
1234567 101 - 150 of 1064
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • harvard-cite-them-right
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 101.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Fast, Lars
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Persson, Nils-Krister
    University of Borås, Swedish School of Textiles.
    Electrical Resistance Measurement Methods and Electrical Characterization of Poly(3,4-ethylenedioxythiophene)- Coated Conductive Fibers2012In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 124, no 4, p. 2954-2961Article in journal (Refereed)
    Abstract [en]

    Textile fibers and yarns of high conductivity, and their integration into wearable textiles for different electronic applications, have become an important research field for many research groups throughout the world. We have produced novel electrically conductive textile yarns by vapor-phase polymerization (VPP) of a conjugated polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), on the surface of commercially available textile yarns (viscose). In this article, we have presented a novel setup for electrical resistance measurements, which can be used not only for fibrous structures but also for woven structures of specific dimensions. We have reported a two-point resistance- measuring method using an already manufactured setup and also a comparison with the conventionally used method (so-called crocodile clip method). We found that the electrical properties of PEDOT-coated viscose fibers strongly depend on the concentration of oxidant (FeCl3)and the doping (oxidation) process of PEDOT. To evaluate the results, we used mass specific resistance values of PEDOT-coated viscose yarns instead of normal surface resistance values. The voltage–current (V–I) characteristics support the ohmic behavior of coated fibers to some extent. Monitoring of the charging effect of the flow of current through conductive fibers for prolonged periods of time showed that conductivity remains constant. The change in electrical resistance values with increase in the length of coated fibers was also reported. The resistance measuring setup employed could also be used for continuous measurement of resistance in the production of conductive fibers, as well as for four-point resistance measurement.

  • 102.
    Bashir, Tariq
    et al.
    University of Borås, Faculty of Textiles, Engineering and Business.
    Karlsson, Fredrik
    Söderlöv, Erik
    Persson, Nils-Krister
    University of Borås, Faculty of Textiles, Engineering and Business.
    Cellulosic Smart Textile Fibers based on Organic Electronics2016Conference paper (Refereed)
    Abstract [en]

    The paradigm shift of merging structural properties of materials with other functionalities prevails and cellulose based fibres are no exception. For the realisation of so called smart materials, including smart textiles, electrical conductivity is of special importance, enabling sensorics, signal transmission, energy supply, energy generation, and actuation. We here discuss taking use of the advancement within the organic electronics community of conjugated polymeric systems producing smart textile fibres for inclusion into garment as well as interior and technical textiles. Specifically, poly(3,4-ethylenedioxythiophene) known as PEDOT is studied as a model system. PEDOT has relevance being a working horse within the organic electronics community. Our emerging pilot line is based on creating conductivity by vapour polymerization of EDOT monomers on an oxidant coated textile fibre where these could be taken from arrange of materials. Here we focus on cellulose based fibres. It is shown that Tencell-Lyocell is a suitable substrate offering many  anchoring sites and that multiple depositions with layers deposited directly on each other decreased the resistance from 5.1 (± 1.6) kΩ/10 cm to 1.0 (± 0.1) kΩ/10 cm, for one layer and multiple layers respectively. Furthermore, adding 15 wt. % of the copolymer PEG-PPG-PEG to the oxidant solution decreased the resistance from 6.8 (± 1.2) kΩ/10 cm to 3.9 (± 0.8) kΩ/10 cm.

  • 103.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Naeem, Jawad
    Persson, Nils-Krister
    University of Borås, School of Engineering.
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    FUNCTIONAL TEXTILES: Micro-porous Conductive Membranes for Bio-fuel Cell and Anti-static Air Filter Applications2013Conference paper (Refereed)
    Abstract [en]

    Conductive membranes are the highly demanding materials in the field of bio-fuel generation, bio-electrodes, sensors and anti-static air filter systems. The conductive membranes can effectively be utilized for above mentioned applications if they have better conductivity, lower weight, flexibility and cost effectiveness. Textile materials are extremely versatile in nature because their synergic combinations with other functional materials could be used for a wide range of applications, such as medical, sports, defence, energy generation and chemical industry. The non-woven micro-porous textile substrates can effectively be functionalized by coating them with conjugated polymers, such as PEDOT and polypyrrole. Coating with conjugated polymers not only gives better conductivity values but also maintain the lower molecular weight of the substrate material. In our research, we have prepared micro-porous conductive membranes by coating cellulosic non-woven fabrics with conductive polymer PEDOT. For coating purpose, we utilized most effective deposition technique, which is called chemical vapour deposition (CVD) process. The deposition of PEDOT by CVD process showed advantages over other conventionally used methods, such as the micro-pores were not blocked even after PEDOT deposition. The electrical characterization on produced conductive membranes was performed by using Kiethely 6000 picoammeter. The surface morphology was examined by scanning electron microscopy and structural properties were determined by ATR-FTIR analysis. In order to see the behaviour of these conductive membranes, electrochemical impedance scanning (EIS) was performed in different electrolyte solutions. The produced conductive membranes might have potential to be utilized as active electrode in bio-fuel cells and also can be used in anti-static air filter systems.

  • 104.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Naeem, Jawad
    Persson, Nils-Krister
    University of Borås, School of Engineering.
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Functionalization of Textile Materials by Coating with Conjugated Polymers2013Conference paper (Refereed)
    Abstract [en]

    During the last decade, smart textiles have attracted an enormous attention of researchers and found extraordinary applications in biomedical, sports, defense, energy, and fashion industry. These textiles are able to accept the physical signals from external stimuli and then generate a reaction in the form of thermal, electrical, chemical and magnetic signals. They should be in the form of functionalized fabric or electro-active fibers. A numerous techniques for the production of electrically conductive fibers have already been developed. In this study, we have prepared relatively highly conductive fibers with better mechanical properties. For this purpose, we have functionalized the commercially available textile fibers by coating with intrinsically conductive polymer (ICP), poly(3,4-ethylenedioxythiophene) (PEDOT). An efficient coating technique, so called oxidative chemical vapor deposition (CVD) was utilized for making uniform, thin and highly conductive polymer layers on the surface of textile fibers. For our initial experiments, we used viscose and polyester fibers as substrate materials. After performing a series of experiments, we have optimized a number of reaction parameters at which good electro-mechanical properties of conductive fibers can be achieved. At specific reaction conditions, the conductivity level which we have attained is approximately 15 S/cm. The PEDOT coated viscose and polyester fibers were compared in order to find out the best suitable substrate material. For increasing the service life of obtained conductive fibers, a thin layer of silicon resin was applied on the surface of PEDOT coated fibers.

  • 105.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Naeem, Jawad
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Persson, Nils-Krister
    Synthesis of electro-active membranes by chemical vapor deposition (CVD) process2014In: Polymers for Advanced Technologies, ISSN 1042-7147, E-ISSN 1099-1581, Vol. 25, no 12, p. 1501-1508Article in journal (Refereed)
    Abstract [en]

    In the past two decades, many research is being carried out on coating of textile membranes with conductive polymers. In order to functionalize the textile membranes, coating of different intrinsically conductive polymers can be applied on these membranes through appropriate coating techniques like electrochemical polymerization, wet chemical oxidation and chemical vapor deposition(CVD. Noticeably, CVD process is one of the most suitable and environment friendly technique. In this research, microporous polyester and polytetrafluoroethylene (PTFE) membranes were coated with conductive poly(3,4-ethylenedioxythiophene) (PEDOT) by CVD process in the presence of ferric(III)chloride (FeCl3) used as an oxidant. Polymerization of PEDOT on the surface of membranes and pore size was examined by optical microscope and scanning electron microscopy (SEM). Structural analysis investigated with ATR-FTIR, which revealed the successful deposition of PEDOT on membranes without damaging their parent structures. The amount of PEDOT in PEDOT-coated polyester and PTFE membranes was explored with the help of thermogravimeteric analysis. Electrical resistance values of PEDOT-coated membranes were measured by two probe method. The effect of different electrolyte solutions such as, distilled H2O, Na2SO4, HCl, and H2SO4 on electrical properties of produced conductive membranes was investigated after dipping for certain period of time. It was found that membranes dipped in H2SO4 show very low electrical resistance values, i.e. 0.85 kΩ for polyester membrane and 1.17 kΩ for PTFE membrane. The obtained PEDOT-coated electro-active membranes may find their possible utility in fuel cells, enzymatic fuel cells, and antistatic air filter applications.

  • 106.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Persson, Nils-Krister
    University of Borås, School of Engineering.
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Smart Textiles: A novel concept of functionalizing textile materials2013Conference paper (Refereed)
    Abstract [en]

    Electrically conductive textile materials are the key components in smart and interactive textile applications. In our research, we introduced functionalities in commercially available textile substrates (fibers and fabrics) by coating them with conjugated polymer, such as poly (3,4-ethylenedioxythiophene) (PEDOT) [1-2]. In order to get conductivities that are of use, an efficient technique, chemical vapor deposition (CVD), was used. The obtained coated fibers and fabrics exhibited good electro-mechanical properties and can be utilized for a number of electronic applications, such as stretch sensors, anti-static air filters and electrodes for bio-fuel cells.

  • 107.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Persson, Nils-Krister
    Electroactive textile fibers produced by coating commercially available textile fibers with conductive polymer2010In: Nordic Textile Journal, ISSN 1404-2487Article in journal (Refereed)
    Abstract [en]

    The development of electrically conductive fibers, exhibiting higher mechanical properties and their integration in smart and interactive textiles, has become a prominent research area throughout the world. Smart textiles have increasingly been used in medical, sports and military applications. In other words, we can say, smart textiles are going to shape our future. This paper describes our ongoing research in which, we have produced relatively highly conductive fibers by coating commercially available textile fibers (viscose, polyester) with conductive polymer, poly(3,4-ethylenedioxythiophene) (PEDOT). A novel coating technique, called oxidative chemical vapor deposition (OCVD), was used for this purpose. Different testing and characterization techniques were then employed to investigate electrical, mechanical, thermal, and surface properties of PEDOT coated fibers. The surface modification of electrically conductive textile fibers with silicone resins is also discussed and an analysis is given to show how silicone coating enhances the mechanical as well as hydrophobic properties of coated textile fibers. The obtained PEDOT coated textile fibers showed good electrical as well as mechanical properties. From this research, we can easily select the most appropriate type of fiber according to the specific electronic application, exhibiting the required end-used properties. These conductive fibers could also be used as substrates for heat generation devices, such as solar cells, and organic fuel cells.

  • 108.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Persson, Nils-Krister
    University of Borås, School of Engineering.
    Oxidative Chemical Vapour Deposition Polymerization of Poly (3,4-ethylenedioxythiophene) on Viscose Yarns: A Route to Conductive Textile Structures2010Conference paper (Refereed)
  • 109.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Persson, Nils-Krister
    University of Borås, School of Engineering.
    Production of conductive yarns by chemical vapour deposition technique of PEDOT viscose fibres2010Conference paper (Refereed)
  • 110.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Persson, Nils-Krister
    Production of Highly Conductive Textile Viscose Yarns by Chemical Vapor Deposition Technique: A Route to Continuous Process2010In: Polymers for Advanced Technologies, ISSN 1042-7147, E-ISSN 1099-1581, Vol. 22, no 12, p. 2214-2221Article in journal (Refereed)
    Abstract [en]

    An oxidative chemical vapor deposition (OCVD) process was used to coat flexible textile fiber (viscose) with highly conductive polymer, poly (3,4-ethylenedioxythiophene) (PEDOT) in resence of ferric (III) chloride (FeCl3) oxidant. OCVD is a solvent free process used to get uniform, thin, and highly conductive polymer layer on different substrates. In this paper, PEDOT coated viscose fibers, prepared under specific conditions, exhibited high conductivity 14.2 S/cm. The effects of polymerization conditions, such as polymerization time, oxidant concentration, dipping time of viscose fiber in oxidant solution, and drying time of oxidant treated viscose fiber, were carefully investigated. Scanning electron microscopy (SEM) and FT-IR analysis revealed that polymerization of PEDOT on surface of viscose fiber has been taken place and structural analysis showed strong interactions between PEDOT and viscose fiber. Thermogravimetric analysis (TGA) was employed to investigate the amount of PEDOT in PEDOT coated viscose fiber and interaction of PEDOT with viscose fiber. The effect of PEDOT coating on the mechanical properties of the viscose fiber was evaluated by tensile strength testing of the coated fibers. The obtained PEDOT coated viscose fiber having high conductivity, could be used in smart clothing for medical and military applications, heat generation, and solar cell demonstrators.

  • 111.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Persson, Nils-Krister
    [external].
    Production of PEDOT Coated Conductive Fibers for Smart & Interactive Textile Applications2012Conference paper (Refereed)
  • 112.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Persson, Nils-Krister
    Surface Modification of Conductive PEDOT Coated Textile Yarns with Silicone Resin2011In: Materials technology (New York, N.Y.), ISSN 1066-7857, E-ISSN 1753-5557, Vol. 26, no 3, p. 135-139Article in journal (Refereed)
    Abstract [en]

    Electroactive textile fibres and fabrics have been used in smart and interactive clothing for medical,military and sports applications. The improved surface properties of conductive textiles are required for their successful integration in all of the above mentioned applications. This paper presents the production of conductive poly(3,4-ethylenedioxythiophene) (PEDOT) coated viscose yarns in longer length, i.e. 5 m, and the surface modification of the coated yarns by treating with silicone solution. The structural properties of silicone coated conductive yarns were then investigated by Fourier transform infrared spectroscopy and thermogravimetric analysis. The effect of silicone coating on the mechanical, electrical and hydrophobic properties was also evaluated and then compared with the PEDOT coated viscose yarns without surface treatment. Results show that the mechanical and hydrophobic properties of conductive yarns were improved by surface modification with silicone without affecting their structural properties. The surface modified PEDOT coated yarns could be used as pressure and stretch sensors in health care applications.

  • 113.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Persson, Nils-Krister
    Synthesis of High Performance, Conductive PEDOT-coated Polyester Yarns by OCVD Technique2012In: Polymers for Advanced Technologies, ISSN 1042-7147, E-ISSN 1099-1581, Vol. 23, no 3, p. 611-617Article in journal (Refereed)
    Abstract [en]

    Production of high performance conductive textile yarn fibers for different electronic applications has become a prominent area of many research groups throughout the world. We have used oxidative chemical vapor deposition (OCVD) technique to coat flexible and high strength polyester yarns with conjugated polymer, poly(3,4- ethylenedioxythiophene) (PEDOT) in presence of ferric (III) chloride (FeCl3) oxidant. OCVD is an efficient solvent free technique used to get uniform, thin, and highly conductive polymer layers on different substrates. In this paper, PEDOT-coated polyester (PET) yarns were prepared under specific reaction conditions, and the electrical, mechanical and thermal properties were compared to previously studied PEDOT-coated viscose yarns. Scanning electron microscopy (SEM) and FT-IR analysis revealed that polymerization of PEDOT on the surface of the polyester yarns has been taken place successfully and structural analysis showed that PEDOT has strong interactions with viscose yarns as compared to PET yarns. The voltage–current (V–I) characteristics showed that PET yarns are more conductive than PEDOT-coated viscose yarns. The variation in the conductivity of PEDOT-coated yarns and the heat generation properties during the flow of current through coated yarns for longer period of time, was studied by time–current (t–I) characteristics. Thermogravimeteric analysis (TGA) was employed to investigate the thermal properties and the amount of PEDOT in PEDOT-coated PET yarns compared to PEDOT-coated viscose. The effect of PEDOT coating and ferric (III) chloride concentration on the mechanical properties of coated yarns was evaluated by tensile testing. The obtained PEDOT-coated conductive polyester yarns could be used in smart clothing for medical and military applications.

  • 114.
    Bashir, Tariq
    et al.
    University of Borås, School of Engineering.
    Skrifvars, Mikael
    University of Borås, School of Engineering.
    Ramamoorthy, Sunil Kumar
    Persson, Nils-Krister
    University of Borås, School of Engineering.
    All-organic conductive fibers for smart and interactive textile applications2013Conference paper (Other academic)
  • 115. Baudlot, Fanny
    et al.
    Engholm, Emil
    Adoption of mobile payment methods, a challenge for the senior citizens of Sweden?2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    For the first time ever, mobile payments in Sweden have overtaken cash as the preferred method of payment when it comes to monthly payments. With cashless payments growing in Sweden and all over the world it is clear that mobile payment methods are going to increase in our everyday lives. As elders tend to have more difficulties learning and understanding software, it is not unlikely that this will affect the adoption of mobile payment methods. As cash is rapidly disappearing as a payment method in Sweden it is important to gain insight into which factors affect the acceptance of mobile payment methods among senior citizens, as they are the most frequent users of cash today. This is a qualitative case study where five seniors have been interviewed about their opinions on mobile payments based on a theoretical model of mobile adoption consisting of eleven variables. The interviews came to center around the Swedish mobile payment application Swish as it was the only mobile payment service that the participants were aware of and had experience using. The study’s goal is to gain knowledge of what variables are of importance to the senior consumers when deciding whether or not to adopt a mobile payment system. The main findings of the study are that the variables: social influence, attractiveness of alternatives and trust are the variables that have been seen to affect the senior citizens' adoption of mobile payment the most.

  • 116.
    Bazooyar, Faranak
    et al.
    University of Borås, Faculty of Textiles, Engineering and Business.
    Bohlén, Martin
    University of Borås, Faculty of Textiles, Engineering and Business.
    Bolton, Kim
    University of Borås, Faculty of Textiles, Engineering and Business.
    Computational Studies of Water and Carbon Dioxide Interactions with Cellobiose2015In: Journal of Molecular Modeling, ISSN 1610-2940, E-ISSN 0948-5023, Vol. 21, p. 2553-Article in journal (Refereed)
    Abstract [en]

    B3LYP/6-311++G** with dispersion correction (DFT-D) was used to study local and global minimum energy structures of water (H2O) or carbon dioxide (CO2) bonding with a pair of cellobiose molecules. The calculations showed that neither the H2O nor the CO2 prefer to be between the cellobiose molecules, and that the minimum energy structures occur when these molecules bond to the outer surface of the cellobiose pair. The calculations also showed that the low energy structures have a larger number of inter-cellobiose hydrogen bonds than the high energy structures. These results indicate that penetration of H2O or CO2 between adjacent cellobiose pairs, which would assist steam or supercritical CO2 (SC-CO2) explosion of cellulose, is not energetically favored. Comparison of the energies obtained with DFT-D and DFT (the same method but without dispersion correction) show that both hydrogen bonds and van der Waals interactions play an important role in cellobiose-cellobiose interactions.

  • 117.
    Bazooyar, Faranak
    et al.
    University of Borås, School of Engineering.
    Bolton, Kim
    University of Borås, School of Engineering.
    Molecular-level Simulations of Cellulose Dissolution by Steam and SC-CO2 Explosion2014Conference paper (Refereed)
    Abstract [en]

    Dissolution of cellulose is an important but tough step in biofuel production from lignocellulosic materials. Steam and supercritical carbon dioxide (SC-CO2) explosion are two effective methods for dissolution of some lignocellulosic materials. Loading and explosion are the major processes of these methods. Studies of these processes were performed using grand canonical Monte Carlo and molecular dynamics simulations at different pressure/ temperature conditions on the crystalline structure of cellulose. The COMPASS force field was used for both methods. The validity of the COMPASS force field for the calculations was confirmed by comparing the energy and structures obtained from molecular mechanics simulations of cellobiose (the repeat unit of cellulose), water–cellobiose, water-cellobiose pair and CO2-cellobiose pair systems with those obtained from first principle calculations with and without dispersion correction. A larger disruption of the cellulose crystal structure was seen during loading than that during the explosion process. This is seen by an increased separation of the cellulose chains from the centre of mass of the crystal during the initial stages of the loading, especially for chains in the outer shell of the crystalline structure. Reducing and non-reducing ends of the cellulose crystal show larger disruption than the central core; this leads to increasing susceptibility to enzymatic attack in these end regions. There was also change from the syn to the anti torsion angle conformations, especially for chains in the outer cellulose shell. Increasing the temperature increases the disruption of the crystalline structure during loading and explosion.

  • 118.
    Bazooyar, Faranak
    et al.
    University of Borås, Faculty of Textiles, Engineering and Business.
    Bolton, Kim
    University of Borås, Faculty of Textiles, Engineering and Business.
    Molecular-level Simulations of Cellulose Steam Explosion2015In: Quantum Matter, ISSN 2164-7615, Vol. 4, no 2, p. 115-122Article in journal (Refereed)
    Abstract [en]

    Grand canonical Monte Carlo and molecular dynamics simulations are used to study steam explosion of crystalline cellulose using 100, 160, 210 and 250 °C saturated steam. The simulations are based on the COMPASS force field, which provides a valid description of the cellulose crystal structure and water-cellobiose interactions. Disruption of the crystal structure during steaming is typically larger than that during the explosion stage and the restructuring is larger at increased temperature and pressure. This is seen by an increased separation of the cellulose chains from the center of mass of the crystal during the initial stages of the steaming, especially for chains in the outer shell of the elementary fibril. There is a large change in the radius of gyration and fraction of anti torsion angle conformers for chains in the outer shell of the elementary fibril. In addition, the disruption at the reducing and non-reducing ends of the cellulose crystal is larger than in the central core, increasing susceptibility to enzymatic attack in these end regions.

  • 119.
    Bazooyar, Faranak
    et al.
    University of Borås, School of Engineering.
    Momany, Frank A.
    Bolton, Kim
    University of Borås, School of Engineering.
    Validating Empirical Force Fields for Molecular-level Simulation of Cellulose Dissolution2012In: Computational and Theoretical Chemistry, ISSN 2210-271X, E-ISSN 2210-2728, Vol. 984, p. 119-127Article in journal (Refereed)
    Abstract [en]

    The calculations presented here, which include dynamics simulations using molecular mechanics forcefields and first principles studies, indicate that the COMPASS forcefield is preferred over the Dreiding and Universal forcefields for studying dissolution of large cellulose structures. The validity of these forcefields was assessed by comparing structures and energies of cellobiose, which is the shortest cellulose chain, obtained from the forcefields with those obtained from MP2 and DFT methods. In agreement with the first principles methods, COMPASS is the only forcefield of the three studied here that favors the anti form of cellobiose in the vacuum. This forcefield was also used to compare changes in energies when hydrating cellobiose with 1–4 water molecules. Although the COMPASS forcefield does not yield the change from anti to syn minimum energy structure when hydrating with more than two water molecules – as predicted by DFT – it does predict that the syn conformer is preferred when simulating cellobiose in bulk liquid water and at temperatures relevant to cellulosedissolution. This indicates that the COMPASS forcefield yields valid structures of cellulose under these conditions. Simulations based on the COMPASS forcefield show that, due to entropic effects, the syn form of cellobiose is energetically preferred at elevated temperature, both in vacuum and in bulk water. This is also in agreement with DFT calculations.

  • 120.
    Beach, Dennis
    et al.
    University of Borås, School of Education and Behavioural Science.
    Player-Koro, Catarina
    University of Borås, School of Education and Behavioural Science.
    Authoritative Knowledge in Initial Teacher Education: Studying the Role of Subject Textbooks through Two Ethnographic Studies of Mathematics Teacher Education.2012In: Journal of Education for Teaching, ISSN 0260-7476, E-ISSN 1360-0540, Vol. 38, no 2, p. 115-125Article in journal (Refereed)
    Abstract [en]

    Two related ethnographic research projects on mathematics teacher education in Sweden are presented in this paper. They represent a response to recent policy developments that reaffirm the value of authoritative subject studies content as the central and most important component in the professional knowledge base of would-be teachers and concomitant increases in the amount of subject studies in teacher education. These policy changes, in Sweden at least, lack scientific research support and the article argues that these policies need to be seriously rethought, as the increased emphasis on subject content may undermine the development of key professional skills.

  • 121.
    Beculic, Mirza
    et al.
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    Blazevic, Vedran
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    Draganovic, Majda
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    Lyckade IT-projekt: Hur framhävs den mänskliga faktorn inom IT-projekt2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    IT - projekt har ökat kraftigt under det senaste decenniet, många framgångsfaktorer har då identifierats. Mycket forskning har gjorts under åren men fokus har då varit på arbetsprocesser inom IT-projekt. Under årens lopp har forskning inom de mänskliga framgångsfaktorerna inte varit lika attraktiv. Trots att forskare har identifierat att de mänskliga framgångsfaktorerna är en av de största framgångsfaktorerna för lyckade IT-projekt, vi har under en teoretisk undersökning märkt att företag inte prioriterar den mänskliga framgångsfaktorn.Vår utgångspunkt för studien har varit den teoretiska undersökningen för uppgiften, vi har samlat in material via databaser, Internet och biblioteksböcker. Undersökningen av teorin visade snabbt att vi inte kunde besvara vår forskningsfråga. Vi var därför tvungna att ge oss ut på fältet för att kunna besvara vår forskningsfråga.Denna forskning går igenom vad mänskliga framgångsfaktorer är och hur det kan hanteras så att det slutliga resultatet av IT-projektet ger en ökad chans till att IT-projektet lyckas. Resultatet av denna uppsats är att belysa hur mycket den mänskliga framgångsfaktorn faktiskt kan påverka resultatet av ett IT - projekt.

  • 122.
    Bengtsson, Anders
    University of Borås, School of Engineering.
    A Riccati type PDE for light-front higher helicity vertices2014In: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, Vol. 9, no 105Article in journal (Refereed)
    Abstract [en]

    This paper is based on a curious observation about an equation related to the tracelessness constraints of higher spin gauge fields. A similar equation also occurs in the theory of continuous spin representations of the Poincaré group. Expressed in an oscillator basis for the higher spin fields, the equation becomes a non-linear partial differential operator of the Riccati type acting on the vertex functions. The consequences of the equation for the cubic vertex is investigated in the light-front formulation of higher spin theory. The vertex is fixed by the PDE up to a set of terms that can be considered as boundary data for the PDE. These terms can serve as off-shell quantum corrections. In order to set the present work in perspective, some comments and comparisons to recent research on higher spin interactions are made. A few particular cubic vertices are calculated explicitly and compared to similar results in the literature, in particular the interesting cases 2 ÿ 3 ÿ 3 and 3 ÿ 2 ÿ 2 involving spin 2 fields.

  • 123.
    Bengtsson, Anders
    University of Borås, School of Engineering.
    An Abstract Interface to Higher Spin Field Theory2005In: Journal of Mathematical Physics, ISSN 0022-2488, E-ISSN 1089-7658, Vol. 46, no 4Article in journal (Refereed)
  • 124.
    Bengtsson, Anders
    University of Borås, School of Engineering.
    BRST theory for continuous spin2013In: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, Vol. 108, no 10Article in journal (Refereed)
    Abstract [en]

    Some puzzling aspects of higher spin field theory in Minkowski space-time, such as the tracelessness constraints and the search for an underlying physical principle, are discussed. A connecting idea might be provided by the recently much researched continuous spin representations of the Poincaré group. The Wigner equations, treated as first class constraints, yields to a four-constraint BRST formulation. The resulting field theory, generalizing free higher spin field theory, is one among a set of higher spin theories that can be related to previous work on unconstrained formulations. In particular, it is conjectured that the unconstrained higher spin theory of Francia and Sagnotti is a limit of a continuous spin theory. Furthermore, a simple analysis of the constraint structure reveals a hint of a physical rationale behind the trace constraints.

  • 125.
    Bengtsson, Anders
    University of Borås, Faculty of Textiles, Engineering and Business.
    Investigations into light-front interactions for massless fields (I): Non-constructibility of higher spin quartic amlplitudes2016In: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, Vol. 12, p. 134-, article id 134Article in journal (Refereed)
    Abstract [en]

    The dynamical commutators of the light-front Poincar{\'e} algebra yield first order differential equations in the $p^+$ momenta for the interaction vertex operators. The homogeneous solution to the equation for the quartic vertex is studied. Consequences as regards the constructibility assumption of quartic higher spin amplitudes from cubic amplitudes are discussed. The existence of quartic contact interactions unrelated to cubic interactions by Poincar{\'e} symmetry indicates that the higher spin S-matrix is not constructible. Thus quartic amplitude based no-go results derived by BCFW recursion for Minkowski higher spin massless fields may be circumvented.

  • 126.
    Bengtsson, Anders
    University of Borås, School of Engineering.
    Light-front higher-helicity interactions2012In: Fortschritte der Physik. Special Issue: Proceedings of the XVIIthe European Workshop on String Theory 2011, Padua, Italy, 4-9 September 2011 (part 2), Wiley , 2012, p. 1038-1043Conference paper (Refereed)
    Abstract [en]

    The reformulation, using Fock space vertex operators, of the original light-front cubic interaction terms for higher spin gauge fields is reviewed with comments on quantum higher spin gravity. The formalism is generalized to all orders in the interaction. The ensuing recursive equations for the higher order vertices, if they can be explicitly solved, will encode all interaction data into a denumerable set of rational functions of p+, the overall transverse momentum structure being fixed already at the kinematical level. A more thorough exposition can be found in the archive.

  • 127.
    Bengtsson, Anders
    University of Borås, School of Engineering.
    Mechanical Models for Higher Gauge Fields2009In: Fortschritte der Physik, ISSN 0015-8208, E-ISSN 1521-3978, Vol. 57, no 5-7, p. 499-504Article in journal (Refereed)
  • 128.
    Bengtsson, Anders
    University of Borås, Faculty of Textiles, Engineering and Business.
    Notes on Cubic and Quartic Light-Front KinematicsManuscript (preprint) (Other academic)
    Abstract [en]

    The purpose of this short note is to collect a set of formulas pertaining to momentum kinematics for higher spin light-front vertices. At least one of the formulas seems to be previously unknown.

  • 129.
    Bengtsson, Anders
    University of Borås, Faculty of Textiles, Engineering and Business.
    Quartic amplitudes for Minkowski higher spin2016In: Higher Spin Gauge Theories / [ed] Lars Brink, Marc Henneaux, Mikhael A Vasiliev, Singapore: World Scientific, 2016, p. 353-370Chapter in book (Other academic)
    Abstract [en]

    The old problem of finding general quartic interaction terms between fields of higher helicities on the light-front is discussed from the point of view of calculating the corresponding amplitudes directly from the cubic vertices using BCFW recursion. Amplitude based no-go results that has appeared in the literature are reviewed and discussed and it is pointed out how they may perhaps be circumvented.

  • 130.
    Bengtsson, Anders
    University of Borås, School of Engineering.
    Structure of Higher Spin Gauge Interactions2007In: Journal of Mathematical Physics, ISSN 0022-2488, E-ISSN 1089-7658, Vol. 48, no 7Article in journal (Refereed)
  • 131.
    Bengtsson, Anders
    University of Borås, School of Engineering.
    Systematics of Higher-spin Light-front Interactions2012In: arXivArticle in journal (Other academic)
    Abstract [en]

    The original cubic interaction terms for higher spin gauge fields in four dimensions and their reformulation using Fock space vertex operators is reviewed. As a new result, the complete list of all cubic vertex functions in D=4 is derived. It is observed, contrary to what would have been expected, that the non-linear dynamical Poincar\'e transformations do not restrict the cubic interactions beyond what is required by kinematics. The role of the SU(1,1) algebra of tracelessness constraints is clarified. It is shown that higher spin fields couple non-minimally to gravity at the cubic level in D=4 light-front dynamics. Based on a detailed analysis of the structure of the light-front Poincar\'e algebra, the formalism is then generalized to all orders in the interaction. The interacting theory, being a deformation of the free theory, takes the form of a strongly homotopy Lie algebra. It is conjectured that the ensuing recursive equations, if they can be explicitly solved, will encode all interaction data into a denumerable set of functions of p+, the overall transverse momentum structure being fixed already at the kinematical level.

  • 132.
    Bengtsson, Anders
    et al.
    University of Borås, School of Engineering.
    Brink, Lars
    Kim, Sung-Soo
    Counterterms in gravity in the light-front formulation and a D = 2 conformal-like symmetry in gravity2013In: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, Vol. 118, no 3Article in journal (Refereed)
    Abstract [en]

    In this paper we discuss gravity in the light-front formulation (light-cone gauge) and show how possible counterterms arise. We find that Poincaré invariance is not enough to find the three-point counterterms uniquely. Higher-spin fields can intrude and mimic three-point higher derivative gravity terms. To select the correct term we have to use the remaining reparametrization invariance that exists after the gauge choice. We finally sketch how the corresponding programme for N = 8 Supergravity should work.

  • 133.
    Bengtsson, Anders
    et al.
    University of Borås, School of Engineering.
    Brink, Lars
    Kim, Sung-Soo
    Counterterms in Gravity in the Light-Front Formulation and a D=2 Conformal-like Summetry in Gravity2013In: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, Vol. 2013, no 3Article in journal (Other academic)
    Abstract [en]

    In this paper we discuss gravity in the light-front formulation (light-cone gauge) and show how possible counterterms arise. We find that Poincare invariance is not enough to find the three-point counterterms uniquely. Higher-spin fields can intrude and mimic three-point higher derivative gravity terms. To select the correct term we have to use the remaining reparametrization invariance that exists after the gauge choice. We finally sketch how the corresponding programme for N=8 Supergravity should work.

  • 134. Bengtsson, Linnéa
    Gränssnitt och identitet inom Tinder och Grindr: Skillnader med avseende på identitetsframställning, funktioner, hierarkier samt presenterat innehåll mellan dejtingapplikationer beroende på syfte och målgrupp2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to gain a more in-depth knowledge and understanding of the dating applications Tinder and Grindr and their structure regarding accented information and identity codes. I intended to gain an understanding of human perception and how this is applied to our modern dating applications. The main focus of the thesis was information hierarchies and visual hierarchies and how people perceive various visual elements. Another relevant aspect was the applications profile settings and self- presentation on the web. The method of the study was a qualitative content analysis with a deductive approach. The empirical material was categorized and summarized in a comparison between the two applications. In the study, discussions arose about the target group and the actual motives of the applications, which was a significant part of the result. Questions about gender, self and other specific identity aspects were also discussed during the study. This essay is written in Swedish.

  • 135. Berg, Anton
    Det som är Roligt, är Roligt2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis explores the perceived enjoyability of Deep Reinforcement learning AI agents (DeepRL agent) that strives towards optimality within the First Person Shooter game Unreal Tournament 2004 (UT2004). The DeepRL agent used in the experiments was created and then trained within this game against the AI agent which comes with the UT2004 game (known here as a trivial UT2004 agent). Through testing the opinions of participants who have played UT2004 deathmatches against both the DeepRL agent and the trivial UT2004 agent, the data collected in two participant surveys shows that the DeepRL agent is more enjoyable to face than a trivial UT2004 agent. By striving towards optimality the DeepRL agent developed a behaviour which despite making the DeepRL agent a great deal worse at UT2004 than the trivial UT2004 agent was more enjoyable to face than the trivial UT2004 agent. Considering this outcome the data suggests that DeepRL agents in UT2004 which are encouraged to strive towards optimality during training are “enjoyable enough” in order to be considered by game developers to be “good enough” when developing non-trivial opponents for games similar to UT2004. If the development time of a DeepRL agent is reduced or equal in comparison with the development time of a trivial agent then the DeepRL agent could hypothetically be preferable. 

  • 136.
    Bergengren, Jakob
    et al.
    Länsstyrelsen i Jönköping.
    Svensson, Jan-Erik
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    von Proschwitz, Ted
    Naturhistoriska museet, Göteborg.
    Lundberg, Stefan
    Naturhistoriska Riksmuseet.
    A recent Dreissena invasion in an old canal system in northern Europe2015Conference paper (Other academic)
    Abstract [en]

    The Göta Canal was opened in 1832 and connects the Baltic and the Atlantic Sea via the large lakes Vänern and Vättern in south Sweden. Originally used for commercial transport, the canal is today one of the most popular tourist attractions in Sweden with canal cruises, pleasure boating and canoeing. Inventories in 2013 showed that Dreissena mussels recently have invaded lakes, streams and canals in the Motala River drainage basin, i.e. the eastern part of the Göta Canal. According to interviews with local people the mussels may have been there since 2012. During the late summer in 2013 and in 2014 we monitored mussels by scuba diving and we sampled planktonic larval populations in locks and the canal. Dreissena has not dispersed to the western part of the canal system, i.e. west of lake Vättern, where most lakes are oligotrophic with low Ca- andMg-levels. In the eastern part, where several lakes are eutrophic and Ca- and Mg-levels higher, populations have increased very fast. The inventories showed local densities of 10 000 adults m-2 in some eutrophic lakes and larval densities of up to 70 individuals L-1 in the canal water. In Europe, the large range expansion of Dreissena occurred during the late 19th and early 20th century. Why have they dispersed so late into the Göta Canal, i.e. some 170 years after the canal was constructed and some 80 years after they had dispersed to other lakes in Swedennorth of Göta Canal? We can not dismiss dispersal as a a limiting factor but given the historically sustained boat traffic in the region it seems likely that ecological factors may have been important. Freshwaters in Scandinavia are usually low in Ca and Mg and many lakes are characterized by oligotrophic conditions poor in food for filter-feeding Dreissena. In the Göta Canal, changes in biological factors affecting relationships between Dreissena and the regional biota needs to be studied, however. Although we can not explain the delayed invasion we conclude that Dreissena is now established in one of the largest canal system in northern Europe.

  • 137.
    Berglin, Lena
    University of Borås, Swedish School of Textiles.
    Interactive Textile Structures: Creating Multifunctional Textiles based on Smart Materials2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Textiles of today are materials with applications in almost all our activities. We wear clothes all the time and we are surrounded with textiles in almost all our environments. The integration of multifunctional values in such a common material has become a special area of interest in recent years. Smart Textile represents the next generation of textiles anticipated for use in several fashion, furnishing and technical textile applications. The term smart is used to refer to materials that sense and respond in a pre-defined manner to environmental stimuli. The degree of smartness varies and it is possible to enhance the intelligence further by combining these materials with a controlling unit, for example a microprocessor. As an interdisciplinary area Smart Textile includes design spaces from several areas; the textile design space, the information technology design space and the design space of material science. This thesis addresses how Smart Textiles affect the textile design space; how the introduction of smart materials and information technology affects the creation of future textile products. The aim is to explore the convergence between textiles, smart materials and information technology and to contribute to providing a basis for future research in this area. The research method is based on a series of interlinked experiments designed through the research questions and the research objects. The experiments are separated into two different sections: interactive textile structures and health monitoring. The result is a series of basic methods for how interactive textile structures are created and a general system for health monitoring. Furthermore the result consists of a new design space, advanced textile design. In advanced textile design the focus is set on the relation between the different natures of a textile object: its physical structure and its structure in the context of design and use.

  • 138.
    Bergnell, Anneli
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    Med kroppen som illustration2019Conference paper (Other academic)
  • 139.
    Bergnell, Anneli
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    Med kroppen som illustration2019Conference paper (Other academic)
  • 140. Bergqvist, Alexander
    et al.
    Carlsson, Andreas
    Mäta och visualisera produktivitet inom ITSM2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    IT Service Management (ITSM) is becoming a more relevant topic and the view of services is growing, therefore it is natural that new difficulties arise. When it comes to the manufacturing industry, it has not been seen as a difficult process to measure productivity. That is because it only refers to the ratio between output and input. However, when it comes to measuring the productivity of a service, many different factors have to be included. This is something several scientists agree to be a more difficult process. This difficulty is causing a lot of problems for businesses whose clients want to know if the service they are paying for is productive or not.

     

    This study aimed at developing a simple prototype that makes it possible to measure the productivity of IT services. Based on previous research and the experience of another company from when they were measuring service productivity, a number of overall goals were set for the prototype. The objectives intended to counteract the problems identified in the previous research and thus the previous research served as a good starting point for the development of the prototype.

     

    This study used design research to develop an innovative artifact, which got evalutated by experienced practitioners during two occasions. The purpose was to identify additional design principles that may be necessary in the development of this type of tool. The development and evaluation were conducted in two iterations. In the first iteration, there was a more informal discussion with an experienced ITSM practitioner about the artifact’s design, allowing for further development of the artifact. The evaluation conducted in the second iteration was more formal and was carried out using a focus group consisting of a number of practitioners with varied knowledge and experience relevant to the area. The obtained results were then compared to theory and previous research to contribute to the conclusions of the study.

     

    The study resulted in two new design principles deemed necessary for this type of measurement tools. The informants and previous researchers’ thoughts about what they considered as important factors were the basis of the design principles. After the implementation of the prototype, there were problems that remained unsolved which were possible to present as future research opportunities. This study does not claim that its results make these kinds of tools complete. There needs to be more research on the subject to optimize the tool further and more design principles may be necessary. This study, on the other hand, may be the basis for future research or for practitioners who choose to implement or develop a similar tool.

  • 141.
    Bergqvist, Martin
    et al.
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    Glansk, Jim
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    Fördelar med att applicera Collaborative Filtering på Steam: En utforskande studie2018Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The use of recommender systems is everywhere. On popular platforms such as Netflix and Amazon, you are always given new recommendations on what to consume next, based on your specific profiling. This is done by cross-referencing users and products to find probable patterns. The aims of this study were to compare the two main ways of generating recommendations, in an unorthodox dataset where “best practice” might not apply. Subsequently, recommendation efficiency was compared between Content Based Filtering and Collaborative Filtering, on the gaming-platform of Steam, in order to establish if there was potential for a better solution. We approached this by gathering data from Steam, building a representational baseline Content-based Filtering recommendation-engine based on what is currently used by Steam, and a competing Collaborative Filtering engine based on a standard implementation.

    In the course of this study, we found that while Content-based Filtering performance initially grew linearly as the player base of a game increased, Collaborative Filtering’s performance grew exponentially from a small player base, to plateau at a performance-level exceeding the comparison. The practical consequence of these findings would be the justification to apply Collaborative Filtering even on smaller, more complex sets of data than is normally done; The justification being that Content-based Filtering is easier to implement and yields decent results. With our findings showing such a big discrepancy even at basic models, this attitude might well change.

    The usage of Collaborative Filtering has been used scarcely on the more multifaceted datasets, but our results show that the potential to exceed Content-based Filtering is rather easily obtainable on such sets as well. This potentially benefits all purchase/community-combined platforms, as the usage of the purchase is monitorable on-line, and allows for the adjustments of misrepresentational factors as they appear.

  • 142. Bergström, Jenny
    et al.
    Clark, Brendon
    Frigo, Alberto
    Mazé, Ramia
    Redström, Johan
    Vallgårda, Anna
    University of Borås, Swedish School of Textiles.
    Becoming materials: material forms and forms of practice2010In: Digital Creativity, ISSN 1462-6268, E-ISSN 1744-3806, Vol. 21, no 3, p. 155-172Article in journal (Refereed)
    Abstract [en]

    As a result of development toward ‘smart’ materials, materials now enable an expanding range of aesthetic expressions and user experiences. These materials are fundamentally temporal in their capacity to assume multiple, discrete states of expression that can be repeatedly and minutely controlled. These materials come to be, or become, only over time and in context—they are becoming materials. Thus, in the development and application of such materials, we must engage more extensively with the experience of materials in practices of design and of use. This paper introduces and discusses the concept of becoming materials—as well as the implications for practice—through a series of examples from our own practice-led research within art, design and architecture. Coming to terms with the implications for material practices of design and of use, we suggest, requires the development of new concepts and methods for doing and studying the design of becoming materials.

  • 143.
    Beronius, Gabriella
    et al.
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    Andrén, Sarah
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    E-Commerce Web design: The importance of a first impression2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The technical society we live in is in a constant state of advancement and we are continuallyintroduced to new innovative ways of mediating information through. Today, plenty of mediachannels exist, for organizations to use when they strive to reach larger groups of people, butto achieve web site success; researchers have stated that considerations of user preferencesimplemented in web design are crucial. This makes understanding and addressing whichcharacteristics will be valued from the moment a user enters a site something that isconsidered helpful to the web designer in order to maintain user traffic and create an interest.In other words, something to catch the user’s attention to create a good first impression is necessary.

    The constant state of advancement of technology prevailing today has resulted in even morecomplex websites and a countless number of design principles to apply when designing forthe web. In spite of this, usability and visual appeal have remained central in prior research.To test these theories, a study was conducted by using a qualitative method in form of anexperiment consisting of eye tracking and an open-ended questionnaire. To perform the eyetracking the researchers created two mock-ups representing the main page of two differentwebsites. Each mock-up was developed with considerations towards two different designapproaches, one striving to achieve visual appeal and the other towards usability, todetermine which one the participants preferred.

    The study contained 50 participants who performed the experiment and answered thequestionnaire. Results from the eye tracking were presented in gaze plots and heat maps andthe result from the questionnaire was presented and analyzed through coding by the researchers.

    Final findings showed that the website preferred by most participants were the one developedwith the usable design approach. Additionally, the discussion presented the findings andreaches a conclusion of the study which finds connections between the chosen designapproach of the webpage and the participant’s choice of preferred webpage.

  • 144. Biamonte, Jacob
    et al.
    Wittek, Peter
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    Pancotti, Nicola
    Rebentrost, Patrick
    Wiebe, Nathan
    Lloyd, Seth
    Quantum Machine Learning2016In: arXiv, article id 1611.09347Article in journal (Other academic)
    Abstract [en]

    Recent progress implies that a crossover between machine learning and quantum information processing benefits both fields. Traditional machine learning has dramatically improved the benchmarking and control of experimental quantum computing systems, including adaptive quantum phase estimation and designing quantum computing gates. On the other hand, quantum mechanics offers tantalizing prospects to enhance machine learning, ranging from reduced computational complexity to improved generalization performance. The most notable examples include quantum enhanced algorithms for principal component analysis, quantum support vector machines, and quantum Boltzmann machines. Progress has been rapid, fostered by demonstrations of midsized quantum optimizers which are predicted to soon outperform their classical counterparts. Further, we are witnessing the emergence of a physical theory pinpointing the fundamental and natural limitations of learning. Here we survey the cutting edge of this merger and list several open problems.

  • 145. Birrell, Duncan
    et al.
    Menzies, Kathleen
    Maceviciute, Elena
    University of Borås, Swedish School of Library and Information Science.
    Wilson, Tom
    University of Borås, Swedish School of Library and Information Science.
    Wollschläger, Thomas
    Konstantelos, Leo
    Innocenti, Perla
    Riestra, Ruben
    Lindh, Maria
    University of Borås, Swedish School of Library and Information Science.
    Harrison, John
    Hasan, Adil
    Zabos, Attila
    Shaman: D14.2 - report on demonstration and evaluation activity in the domain of "memory institututions"2011Report (Other academic)
    Abstract [en]

    1. The report describes the demonstration and evaluation of ISP1, which was designed to demonstrate the potential of the SHAMAN framework for digital preservation in the context of memory institutions and for the research and development community. 2. The demonstration process was carried out by means of presentations based on screen-casts in three locations, Frankfurt, Vilnius and Glasgow. The audiences for the demonstrations consisted persons occupying of a wide range of roles in memory institutions, including senior management, operational level staff and IT support staff. 3. The evaluation is based on the reports of focus groups held in the three locations, together with structured data from self-completed questionnaires, administered on the same occasions. 4. Participants in the focus groups responded favourably to the ideas demonstrated in the presentations. There was particular interest in the choice of mainly open source software and in automation of processes, both of which have cost reduction implications, and in the idea of a digital preservation policy: the majority of participating organizations had no such policy. Participants also drew attention to aspects of preservation which they found lacking in the presentation and which were desirable, specifically: the preservation of font information; working with already obsolete formats; the automatic extraction of necessary metadata; the fact of mixed media archives involving, e.g., film and audio files; support for controlled vocabularies for search and discovery; and demonstration of workflows at a more practical level. 5. The questionnaire results revealed most approval of the retrieval and verification capabilities and less for the ingest processes. Otherwise the results supported the findings from the focus groups in general. There was a division of opinion over the value of the Multivalent browser and the application of grid technology, possibly because of differences in knowledge of these matters. Highest priority was assigned to data migration, access and authentication and bit stream preservation and least to independence standards and search capacity – issues that may be worth further exploration. 6. Evaluation has also been performed to determine the project‟s impact on the R&D community by means of submission and rejection rates of papers to journals and conferences, and bibliometric and Webometric analyses. The results demonstrate that the research outputs from the project are of interest to the R&D community and that the impact of the project as a whole compares favourably with other European projects in the digital preservation area. 7. The evaluation has revealed strengths and shortcomings in the demonstration process, which will influence the development of demonstrators for ISP2 and ISP3. The SHAMAN framework for digital preservation is seen as offering new possibilities and rigorous methods for the field by the practitioners in memory institutions.

  • 146. Björklund, Camilla
    et al.
    Grevholm, Barbro
    Häggström, Johan
    Kjellström, Katarina
    Löfwall, Stefan
    Norén, Eva
    Olofsson, Gunilla
    Persson, Elisabeth
    University of Borås, School of Education and Behavioural Science.
    Persson, Lars-Erik
    Persson, Per-Eskil
    Riesbeck, Eva
    Taflin, Eva
    Lära och undervisa matematik: från förskoleklass till årskurs 62012Book (Other academic)
  • 147. Blom, Alina
    et al.
    Brodin, Frida
    Navigering och användarupplevelse: En studie av navigering på e-handelsplatser med inriktning skönhetsprodukter2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this study, we examined the user experience of horizontal, vertical and faceted navigation on two beauty e-commerce websites. As a data collection method, we conducted user testing with the think aloud method and interviews. The results showed differences in how the users experienced the navigation at the beginning and after use. More specifically, the results showed that users initially expressed negative feelings related to the vertical navigation system, which became more positive after use. Moreover, the study showed that the user experience of the horizontal navigation system changed over time, where the initial experience was more positive than the end experience. The study also revealed various experiences and feelings related to faceted navigation which suggests that the user experience of faceted navigation depends on several different factors which needs to be further explored.

  • 148.
    Bohlén, Martin
    et al.
    University of Borås, School of Engineering.
    Bolton, Kim
    University of Borås, School of Engineering.
    Conformational studies of poly(vinylidene fluoride), poly(trifluoroethylene) and poly(vinylidene fluoride-co-trifluoroethylene) using density functional theory2014In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 16, no 25, p. 12929-12939Article in journal (Refereed)
    Abstract [en]

    Different conformations of systems consisting of poly(vinylidene fluoride) (PVDF), poly(trifluoroethylene) (PTrFE) and poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) were investigated using density functional theory with dispersion correction. It was found that the trans-gauche-trans-gauche´ (TGTG´) conformation of a single PVDF chain is the lowest energy conformer. Crystals of PVDF were modelled using between two to five chains with up to 12 repeat units in each chain and, in agreement with experiment, structures comprised partly or completely of chains with the TGTG´ conformation are more stable than structures built up from chains with all-trans (TTTT) conformation. This indicates that an all-trans segment or chain will not induce the growth of a larger crystal with the same chain conformations. In contrast, the energetically preferred structure of PTrFE chains is an all-trans (TTTT) conformation, and the results indicate that copolymerization of vinylidene fluoride with trifluoroethylene can facilitate the formation of the all-trans PVDF conformations. This is probably due to increased intramolecular repulsion between the fluorine atoms and an increased intermolecular attraction in the crystal structure.

  • 149.
    Bohlén, Martin
    et al.
    University of Borås, School of Engineering.
    Bolton, Kim
    University of Borås, School of Engineering.
    Inducing the piezoelectric β-phase of PVDF: a DFT study2014Conference paper (Refereed)
  • 150.
    Bohlén, Martin
    et al.
    University of Borås, School of Engineering.
    Bolton, Kim
    University of Borås, School of Engineering.
    Inducing the β-phase of poly(vinylidene fluoride): a review2014In: Annual Review of Nanoscience and Nanotechnology, ISSN 2159-9688, Vol. 1, no 1Article in journal (Refereed)
    Abstract [en]

    Poly(vinylidene fluoride) (PVDF) is a versatile material with numerous applications in many fields of industry and science. The extent of applications, ranging from approved contact materials in the food industry to monitors for respiration and heart-rate in medicine, drives the research and development by the materials science community. The largest limiting factor when using PVDF in applications where its piezo- and pyroelectricity is important, is the amount of the highly polar crystalline β-phase in the material. PVDF is polymorphic and usually crystallizes from melt or solution into the non-polar α-phase, which is of little use in piezoelectric applications. Many studies have therefore aimed at increasing the amount of the β-phase crystal structure in the material. Cold drawing of α-phase PVDF, poling in high electric fields, copolymerization with trifluoroethylene, and inclusion of different types of additives to PVDF have been studied using both experimental and computational techniques. This review presents the current status and understanding of these processes, and summarizes results from previous studies. © Global Scientific Publishers 2015.

1234567 101 - 150 of 1064
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • harvard-cite-them-right
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf