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  • 301.
    Samuelsson, C. R.
    et al.
    Uppsala university.
    Elmgren, M.
    Uppsala university.
    Xie, C.
    The Concord Consortium, Concord, Massachusetts.
    Haglund, Jesper
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Going through a phase: Infrared cameras in a teaching sequence on evaporation and condensation2019Inngår i: American Journal of Physics, Vol. 87, nr 7, s. 557-582Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Phase transitions are everyday occurring phenomena, but students often find them difficult to comprehend, not least in terms of the principles of thermal physics. To be able to explain phase transitions in primary school, teachers need to understand various concepts and phenomena, such as condensation, evaporation, energy, and temperature. As energy is absorbed or released during phase transitions, changes in temperature can occur. Infrared (IR) cameras can thus be utilized to visually observe and explore surface phenomena such as condensation and evaporation. In line with the resources framework, we have designed a teaching sequence which involves both everyday experiences and observations through IR cameras, and which is designed to encourage students to leverage common resources associated with evaporation and condensation. In testing our teaching sequence, we presented three thermal phenomena to a group of pre-service teacher students. Two of these phenomena, namely, walking out of a shower and sitting in a sauna, were anchored in embodied experiences to hopefully activate the students’ resources and to make the students pay attention to the thermally relevant aspects. The third phenomenon was less familiar, involving the condensation of water on a piece of paper. The result shows that the students managed to carry out the sequence with the three phenomena and applied an explanatory model across all three to consistently explain evaporation. However, the lack of a more general model of chemical bonding and an overreliance on the second law of thermodynamics seem to have acted as barriers for the students’ forming of a coherent understanding of both evaporation and condensation. © 2019 American Association of Physics Teachers.

  • 302.
    Samuelsson, Christopher Robin
    et al.
    Uppsala universitet.
    Elmgren, Maja
    Uppsala universitet.
    Haglund, Jesper
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013). SMEER.
    Going through a phase: Teaching about energy transformations in phase changes with infrared cameras2018Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Students have difficulties understanding energy transformations involved in phase changes in physics and chemistry education. For example, with a predict-observe-explain set-up, we have found that students tend to intuit that when table salt is poured onto ice, the ice will melt and the temperature increase. They are surprised to see that although the ice melts (due to freezing-point depression), the temperature actually decreases. In this study, we explore how infrared cameras as a visualization technology can help students come to terms with such challenges.

    We have designed a teaching sequence for in-service science teachers on the topic of phase changes, with a focus on the central idea that it requires energy to break bonds between particles. In group discussions, students are encouraged to use this idea to explain how the temperature of water can be constant during phase change from solid to liquid, and from liquid to gas, and draw on their experiences that it feels cold when they walk out of the shower but hot when water is poured onto the stove in a sauna. With the help of an infrared camera, students can see how the temperature decreases as water evaporates from their body. With this technology, they can also see that the temperature of a piece of paper increases as moist air condenses on its surface, and that the temperature decreases when the water evaporates away in dry air. Through video analysis, we study students’ interactions with each other and the types of talk they engage in during the exercises. Early findings in a pilot study with secondary school students indicate that they tend to interpret condensation as release of energy due to particles colliding with a surface, rather than bond formation.

  • 303.
    Samuelsson, Christopher Robin
    et al.
    Uppsala universitet.
    Elmgren, Maja
    Uppsala universitet.
    Haglund, Jesper
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013). SMEER.
    Hot vision: Affordances of infrared cameras in investigating thermal phenomena2019Inngår i: Designs for Learning, ISSN 1654-7608, Vol. 11, nr 1, s. 1-15Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Lab activities typically involve phenomena that are invisible to the naked eye. For example, in thermodynamics transfer of heat and temperature changes are perceived by the sense of touch or indirectly observed by the use of thermometers. New tools can be introduced to increase the opportunities for talking science. In this paper, we explore affordances and semiotic resources related to infrared (IR) cameras, including color imaging, numerical values and the form of the tool itself, as used by undergraduate students and instructors in chemistry, representing a scientific community at two different levels of expertise, in investigation of a thermal phenomenon. The participants come to attend to thermal aspects of what happens when a salt (sodium hydroxide) is exposed to air, with and without the use of IR cameras. Video data were gathered and transcribed multimodally. Results show that the IR cameras afford a focus on the disciplinarily relevant thermal aspects of the phenomenon in both groups of participants, but that the students’ discussion, coordinated by their embodied engagement with the IR cameras, was limited to cumulative talk, where they do not challenge each other, and static use of the technology. This is contrasted with the instructors who shared their knowledge with each other and explored the phenomenon both spatially with the IR cameras, and verbally through exploratory talk. We suggest that this difference in the use of novel technology may be due to differences in experience of lab work and understanding of the studied phenomena, and that a shift between cumulative and exploratory talk may be an indicator of learning.

  • 304.
    Samuelsson, Christopher Robin
    et al.
    Uppsala universitet.
    Haglund, Jesper
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013). SMEER.
    Using infrared cameras in physics and chemistry education2018Konferansepaper (Annet vitenskapelig)
  • 305.
    Sandberg, Patrik
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Hållfasthetsberäkning av handikapanpassad lyftanordning2013Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
  • 306.
    Sandgren, Johan
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Förvarings- och doseringsbehållare för livsmedelspulver: Konstruktion av konsumentprodukt2014Independent thesis Basic level (university diploma), 15 poäng / 22,5 hpOppgave
    Abstract [sv]

    Denna rapport omfattar en produktutvecklingsprocess av en förvarings- och doseringsbehållare för livsmedelspulver. Rapporten är en del av examensarbete för högskoleingenjörer i maskinteknik.

    Konsultföretaget Technogarden Engineering Resources AB i Karlstad har fått i uppdrag av kunden JPRT Förvaltning AB att ta fram ett separat tillbehör till en vällingmaskin som underlättar för konsumenter av denna att underlätta dosering av vällingpulver i dess pulvermagasin.

    Detta innefattar ett konstruktionsarbete där en produktutvecklingsprocess utförts från projektplanering, konceptgenerering, konstruktion, materialval och prototyptillverkning och utvärdering av denna.

    Arbetet är indelat i val av material för den färdiga konstruktionen där materialegenskaper, miljöpåverkan och hälsopåverkan är beslutsgrundande kriterier. Val av koncept har utförts med hjälp av att granska liknande konstruktioner, generera möjliga koncept och på ett objektivt sätt gå vidare med det lämpligaste konceptet för konstruktion. Konstruktion av det valda konceptet görs med hjälp av 3D-CAD som senare ligger till underlag för prototyptillverkning med hjälp av 3D-utskrift i plast. Den färdiga prototypen utvärderas för att finna förbättringsarbete kring denna konstruktion och presentera detta för uppdragsgivaren för att gå vidare med konstruktionen för eventuell produktion.

    Prototypen resulterade i en fungerande konstruktion som kräver vidare detaljkonstruktion, tillverknings- och monteringsanpassning. Vidare underlag såsom materialprover och offertunderlag från leverantörer behövs innan konstruktionen kan tas i produktion.

    Konstruktionen ska användas tillsammans med livsmedel och behöver därför CE-märkas och val av material ska vara godkända av Europeiska kommissionens förordning (EG) nr 10/2011 som måste uppnås vid konstruktion av produkter som är avsedda att vara i kontakt med livsmedel.

    Konstruktionen uppfyller de krav och till stor del de önskemål som satts av uppdragsgivaren och kunden i detta projekt. Några av dessa krav som måste uppfyllas är att behållaren måste rymma en viss mängd vällingpulver, som konstruktionen dimensionerats efter. Konstruktionens doseringsmängd är även anpassad efter pulvermagasinets volym. Då konstruktionen är tänkt för en konsumentmarknad har stor vikt lagts vid att skapa en attraktiv produkt som går i samma formspråk som vällingmaskinen som den är tänkt att användas till. Även ergonomi har varit en faktor att ta hänsyn till i detta projekt och är något som kan behöva vidareutveckla innan konstruktionen tas i produktion. 

  • 307.
    Schelin, Daniel
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Human Body Model Response in Oblique Impacts2013Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
  • 308.
    Sebhatu, Samuel Petros
    et al.
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Centrum för tjänsteforskning.
    Solis, Jorge
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Gebauer, Heiko
    Swiss Federal Institute of Aquatic Science and Technology.
    Value co-creation in a complex service system: A case of Building Robots to innovate service2016Inngår i: The Service Imperatives in the New Economy: Approaches to Service Management and Change. Proceedings., 2016, s. 256-263Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The main objective of this study is to assess and analyze value co-creation in a complex service system from a human-centered point of view. In fulfilling the ambitious goal of integrating cooperative and human-friendly robots, value co-creation should innovate service through the reinvention of the creation of value between robots (i.e., the entire service system) and customers.

    Solving the upcoming challenges of co-creating value in the service sector is related to the method we create well-being in a transformative manner. This method could also use the perspective of service innovation in the complex environment by integrating multiple services that can be adjusted to the specific needs of customers, such as the relatively young and healthy seniors.

    This study is explorative and built around the following concepts based on transformative research: value co-creation, complexity, service innovation, and transformative service. This illustrates these concepts with the case of building robots to provide assistance during activities, such as walking and other physical activities, in an old age house. This study also focuses on describing the challenges of understanding service innovation in the complex service system of service offering toward co-creating value. Such challenges are exemplified from the technical point of view (e.g., multipurpose design concept, human-in-the-loop control, etc.) in the development of a human-friendly walking assistive robot vehicle designed to support the walking activity of relatively young and healthy seniors.

    This study applies the perspective of complexity in service innovation to the case of adding robots in co-creating value. Our findings replicate the theoretical contributions of elements for conceptualizing value co-creation and service innovation in the service systems by adding the roles of robots, namely, interaction between care receiver and robot, as well as care receiver and care givers, among others.

    The current study reveals the challenges of transformative service thinking in the human-centered complex service systems in the manner in which service is innovated and understood, as well as the role of integrating services and well-being. This study aims to describe the challenges of understanding complexity and the role of robot services from the service research perspective.

    Furthermore, this study makes an original contribution to the current discussions on service research toward transformative service and complexity based on services that co-create value. Future research in this area should focus on generalizing the present findings by studying the integration and understanding of service research and transformative service in other empirical settings and conceptualizations.

  • 309.
    Sköld, Jennie
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Ordering of Entangled States for Different Entanglement Measures2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Quantum entanglement is a phenomenon which has shown great potential use in modern technical implementations, but there is still much development needed in the field. One major problem is how to measure the amount of entanglement present in a given entangled state. There are numerous different entanglement measures suggested, all satisfying some conditions being of either operational, or more abstract, mathematical nature. However, in contradiction to what one might expect, the measures show discrepancies in the ordering of entangled states. Concretely this means that with respect to one measure, a state can be more entangled than another state, but the ordering may be opposite for the same states using another measure. In this thesis we take a closer look at some of the most commonly occurring entanglement measures, and find examples of states showing inequivalent entanglement ordering for the different measures.

  • 310.
    Sköld, Simon
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Utveckling av förebyggande underhåll för presspartiet på en pappersmaskin: med ett tillvägagångssätt baserat på TPM2016Independent thesis Basic level (university diploma), 15 poäng / 22,5 hpOppgave
    Abstract [sv]

    Detta projekt är en del av högskoleingenjörsexamen i maskinteknik på Karlstad universitet och utförs på uppdrag av BillerudKorsnäs AB på massa- och pappersbruket Gruvön i Grums. BillerudKorsnäs mäter TAK-värde som är ett mått på den totala utrustningseffektiviteten och för att upprätthålla en hög effektivitet över tid krävs förebyggande underhåll (FU). Under 2015 installerades en skopress som ny andra press i presspartiet på pappersmaskin 6 och den dåvarande andra pressen sattes som första press. Som följd av ombyggnationen behöver FU-åtgärder för presspartiet utvecklas och dokumenteras i företagets underhållssystem vilket är examensarbetets mål. Tillvägagångssättet ska relateras till arbetssättet Total Productive Maintenance (TPM).

    Ur en litteraturstudie inom TPM där fokus legat på operatörsunderhåll och specialistunderhåll har inspiration och information inhämtats för tillvägagångssättet. Inom specialistunderhållet används metoden Reliability Centered Maintenance (RCM) för att optimera underhållsinsatserna och det är metoden RCM som valts att användas under arbetets gång.

    Val av FU-åtgärder har gjorts genom att först samla in information för att kunna kartlägga möjliga avvikelser för respektive objekt i presspartiet och därefter genomföra feleffektsanalys och riskbedömning. Med avseende på riskbedömningen bestäms effektiva och genomförbara FU-åtgärder.

    Utifrån det valda arbetssättet med fokus på RCM som stödjs i TPM har FU-åtgärder för samtliga objekt i presspartiet tagits fram och dokumenterats i företagets underhållssystem. Implementering av dessa åtgärder bidrar till att säkerställa en hög nivå på TAK-värdet och ger även möjlighet till förbättring. Förebyggande underhåll är ett ständigt pågående arbete som hela tiden måste utvecklas och där allas delaktighet är ett måste.

  • 311.
    Solis, Jorge
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    3D gesture recognition system for a dynamically-stable human-friendly robot vehicle2017Konferansepaper (Fagfellevurdert)
  • 312.
    Solis, Jorge
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Development of a human-friendly walking assisting robot vehicle designed to provide physical support to the elderly2016Konferansepaper (Fagfellevurdert)
  • 313.
    Solis, Jorge
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Development of a Human-Friendly Walking Assistive Robot Vehicle2015Inngår i: IROS’2015 Full day Workshop Cognitive Mobility Assistance Robots, 2015, s. 57-60Konferansepaper (Fagfellevurdert)
  • 314.
    Solis, Jorge
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Development of the Human-Friendly Assist Robot Vehicle: Improvement of the velocity control and ramp detection algorithm2016Konferansepaper (Fagfellevurdert)
  • 315.
    Solis, Jorge
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Introducing Practical Issues of Robotics to Master Students2012Inngår i: 13th Mechatronics Forum International Conference, 2012Konferansepaper (Fagfellevurdert)
  • 316.
    Solis, Jorge
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Introduction of Robotics to Master Students at Karlstad University2012Inngår i: 2nd IFToMM Asian Conference in Mechanism and Machine Science, 2012Konferansepaper (Fagfellevurdert)
  • 317.
    Solis, Jorge
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Pilot experiments and velocity control system improvements for the assistive robot vehicle hWALK2016Inngår i: Proc. of the ICRA2016 Workshop on Human-Robot Interfaces for Enhanced Physical Interactions, 2016Konferansepaper (Fagfellevurdert)
  • 318.
    Solis, Jorge
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Pilot Experiments with a Human-friendly Walking Assisting Robot Vehicle2016Inngår i: ROMANSY 21: Robot Design, Dynamics and Control / [ed] W. Schiehlen, V. Parenti-Castelli, Vienna: Springer, 2016, s. 395-402Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Up to now, the embodiment of bodily-kinaesthetic, perceptual and cognitive capabilities for assistive robots has been scarcely studied. This research aims to incorporate and develop the concept of robotic human science and to enable its application in a human-friendly robot for assistive purposes. The author has introduced the development of a human-friendly walking assist robot vehicle designed to provide physical support to the elderly. The proposed system is composed by two-wheeled inverted pendulum mobile robot, a 3-DOFs desktop haptic interface, a mobile computer and a wireless module for communication purposes. Pilot experiments with healthy volunteers were carried out to verify the dynamic stability of the proposed system as well as the possibility to compensate the height error of the HI gripper under uneven terrain conditions.

  • 319.
    Solis, Jorge
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Robot Education with mobile robots2014Inngår i: Designs and Prototypes of mobile robots / [ed] Marco Ceccarelli and Emin Faruk Kekeci (Eds.), ASME Press, 2014, s. 165-185Kapittel i bok, del av antologi (Fagfellevurdert)
  • 320.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Amaral, Fernanda
    Karlstads universitet.
    Denoising of human motion data for a 3D gesture recognition system for a two-wheeled inverted pendulum robot2017Konferansepaper (Fagfellevurdert)
  • 321.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    De la Rosa, Jose Pablo
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Development of a Human-friendly Walking Assistive Robot Vehicle: System Integration and Preliminary Stability Tests2015Konferansepaper (Fagfellevurdert)
  • 322.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Karlsson, Christoffer
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Lindborg, Ann-Louise
    Camanio Care AB.
    Vision-based Detection and Target Positioning for Mobile Robotic Devices2018Konferansepaper (Fagfellevurdert)
  • 323.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Karlsson, Christoffer
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Ogenvall, Mikael
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Lindborg, Ann-Louise
    Camanio Care AB.
    Takeda, Yukio
    Tokyo Institute of Technology.
    Zhang, Cheng
    Waseda University.
    Development of a vision-based feature extraction for food intake estimation for a robotic assistive eating device2018Inngår i: 14th IEEE International Conference on Automation Science and Engineering Munich, Germany, August 20 to 24, 2018, IEEE, 2018, s. 1105-1109Konferansepaper (Fagfellevurdert)
  • 324.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Larsson, Lars-Ove
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Annelie, Boden
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Jeannie, Flognman
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Introducing the principles of robot technology to compulsory school teachers at Karlstad University2014Inngår i: XVI International Organization of Science and Technology Education Symposium, 2014, s. 40-40Konferansepaper (Fagfellevurdert)
  • 325.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Lindborg, Ann-Louise
    Camanio Care AB.
    Saijo, Miki
    Tokyo Institute of Technology.
    Takeda, Yukio
    Tokyo Institute of Technology.
    Japan-Sweden Academia-Industry International Collaboration: Challenges in developing a robotic assistive eating device for frail elderly’s independent life2017Inngår i: CEUR Workshop Proceedings, RWTH Aachen University , 2017, s. 61-65Konferansepaper (Fagfellevurdert)
  • 326.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik. Japan.
    Ng, Kia
    UK.
    Musical Robots and Interactive Multimodal Systems: Overviews the current research on interactive multimodal systems and musical robots2011 (oppl. 1)Bok (Fagfellevurdert)
    Abstract [en]

    Musical robotics is a multi- and trans-disciplinary research area involving a wide range of different domains that contribute to its development, including: computer science, multimodal interfaces and processing, artificial intelligence, electronics, robotics, mechatronics and more. A musical robot requires many different complex systems to work together; integrating musical representation, techniques, expressions, detailed analysis and controls, for both playing and listening. The development of interactive multimodal systems provides advancements which enable enhanced human-machine interaction and novel possibilities for embodied robotic platforms. This volume is focused on this highly exciting interdisciplinary field. This book consists of 14 chapters highlighting different aspects of musical activities and interactions, discussing cutting edge research related to interactive multimodal systems and their integration with robots to further enhance musical understanding, interpretation, performance, education and enjoyment. It is dichotomized into two sections: Section I focuses on understanding elements of musical performance and expression while Section II concentrates on musical robots and automated instruments. Musical Robots and Interactive Multimodal Systems provides an introduction and foundation for researchers, students and practitioners to key achievements and current research trends on interactive multimodal systems and musical robotics.

  • 327.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Ozawa, Kenichiro
    Waseda University.
    Petersen, Klaus
    Waseda University.
    Takanishi, Atsuo
    Waseda University.
    Design and development of a new biologically-inspired mouthmechanism and musical performance evaluation of the WF-4RVI2013Inngår i: Advanced Robotics and its Social Impacts (ARSO), 2013 IEEE Workshop on, IEEE Press, 2013, s. 200-205Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The research on the development of the anthropomorphic flutist robot at Waseda University has been focused in emulating the anatomy and physiology of the organs involved during the flute playing from an engineering point of view, facilitating the symbiosis between the human and the robot (i.e. active interaction between musician and musical robot) and proposing novel applications for humanoid robots (i.e. music education). As a result of this research, the Waseda Flutist Robot No.4 Refined IV has been developed and a musical-based interaction system implemented so the robot is capable of interacting with musicians by processing both aural and visual cues. However; there is a trade-off relationship between the duration of the flute sound produced by the robot and the sound pressure (volume). In fact, the robot is only capable of playing sounds low-pitched sounds for long periods. In addition, a husky sound is detected while playing high-pitch sounds. From our discussions with professional players, this effect is caused due to the inner shape of the oral cavity. From this, the conversion efficiency ratio between from the exhaled air from the artificial lungs to the produced sound is too low. For this purpose, we have obtained MR images of the head from professional players in order to re-design the oral cavity of the flutist robot. A total of 5 prototypes were tested and the best one has been selected and integrated into the Waseda Flutist Robot No. 4 Refined VI (WF-4RVI). A set of experiments were proposed in order to verify the improvements of the conversion efficiency ratio as well as the sound evaluation function score. From the experimental results, we could verify the improvements compared with the previous version of the flutist robot.

  • 328.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Ozawa, Kenichiro
    Waseda University.
    Petersen, Klaus
    Waseda University.
    Takanishi, Atsuo
    Waseda University.
    Development of automatic system to optimize thesound quality and sound pressure of the Waseda Flutist Robot2014Inngår i: Proceedings of The 14th Mechatronics Forum International Conference, Karlstad: Karlstads universitet, 2014, s. 377-383Konferansepaper (Fagfellevurdert)
  • 329.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik. Waseda University.
    Ozawa, Kenichiro
    Waseda University, Japan.
    Takeuchi, Maasaki
    Waseda University, Japan.
    Kusano, Takafumi
    Waseda University, Japan.
    Ishikawa, Shimpei
    Waseda University, Japan.
    Petersen, Klaus
    Waseda University, Japan.
    Takanishi, Atsuo
    Waseda University, Japan.
    Biologically-inspired control architecture for musical performance robots2014Inngår i: International Journal of Advanced Robotic Systems, ISSN 1729-8806, E-ISSN 1729-8814, Vol. 11, s. 172-, artikkel-id 11Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Abstract At Waseda University, since 1990, the authors have been developing anthropomorphic musical performance robots as a means for understanding human control, introducing novel ways of interaction between musical partners and robots, and proposing applications for humanoid robots. In this paper, the design of a biologically-inspired control architecture for both an anthropomorphic flutist robot and a saxophone playing robot are described. As for the flutist robot, the authors have focused on implementing an auditory feedback system to improve the calibration procedure for the robot in order to play all the notes correctly during a performance. In particular, the proposed auditory feedback system is composed of three main modules: an Expressive Music Generator, a Feed Forward Air Pressure Control System and a Pitch Evaluation System. As for the saxophone-playing robot, a pressure-pitch controller (based on the feedback error learning) to improve the sound produced by the robot during a musical performance was proposed and implemented. In both cases studied, a set of experiments are described to verify the improvements achieved while considering biologically-inspired control approaches.

  • 330.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Petersen, K.
    Waseda University.
    Kashiwakura, J.
    Waseda University.
    Saitoh, Y.
    Waseda University.
    Zecca, M.
    Waseda University.
    Takanishi, A.
    Waseda University.
    Development of the Waseda Saxophonist Robot No.2 Refined III: New Air Pump and Eye Mechanism2012Konferansepaper (Fagfellevurdert)
  • 331.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Petersen, Klaus
    Waseda University.
    Takanishi, Atsuo
    Waseda University.
    Biologically-inspired mechanism design for anthropomorphic musical performance robots2014Inngår i: 14th Mechatronics Forum International Conference Mechatronics / [ed] DeVin, L.J., Mechatronics 2014 , 2014, s. 549-554Konferansepaper (Fagfellevurdert)
  • 332.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Sansanayuth, Thitipong
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Shojaei, Efran
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Velocity control improvement for the Human-Friendly Assist Robot Vehicle2016Inngår i: System Integration (SII), 2016 IEEE/SICE International Symposium on / [ed] Book Group Author(s): IEEE, IEEE, 2016, s. 331-336Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Up to now, the embodiment of bodily-kinaesthetic, perceptual and cognitive capabilities for assistive robots has been scarcely studied. This research aims to incorporate and develop the concept of robotic human science and to enable its application in a human-friendly robot for assistive purposes. In this paper, the authors describe the improvements of the velocity control of the two-wheeled inverted pendulum of the hWalk by adding a LQR as compensator for the wheel angular velocity to the existent PID controller. On the other hand, an algorithm based on computing the integral of the motor measured current was proposed in order to detect a ramp in order to cope with inclined surfaces. Experiments were carried out to verify the effectiveness of the proposed velocity control as well as verify the feasibility of the proposed ramp detection algorithm.

  • 333.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013). Karlstad Univ, Dept Engn & Phys, Karlstad, Sweden..
    Sorensen, Anders Stengaard
    Univ Southern Denmark, Dept Hlth Informat & Technol, Odense, Denmark..
    Rasmussen, Gitte
    Univ Southern Denmark, Dept Language & Commun, Odense, Denmark..
    Bodily Human Robot Interaction2019Inngår i: HRI '19: 2019 14TH ACM/IEEE INTERNATIONAL CONFERENCE ON HUMAN-ROBOT INTERACTION, IEEE , 2019, s. 683-684Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This workshop is dedicated to discuss and explore the specific interdisciplinary aspects of Bodily human robot interaction, and establish a common ground for this area as a recognized and continued research topic. Bodily interaction with robots and robotic devices is partially established in niche applications such as exoskeletons, assistive devices and advanced machines for physical training where bodily interaction is the application. Bodily interaction is expected to develop a broader role in human robot interaction, for instance in manufacturing and in social and entertainment robotics. The direct exchange of force and motion in bodily interaction create a range of engineering challenges, but also entwine engineering directly with topics that traditionally reside in the realm of health and humanistic science, from biomechanics to human's social responses to the prompting and responses of physical interaction.

  • 334.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Sugita, Y.
    Waseda University, Japan.
    Petersen, P.
    Waseda University, Japan.
    Takanishi, Atsuo
    Waseda University, Japan.
    Development of an anthropomorphic musical performance robot capable of playing the flute and saxophone: Embedding pressure sensors into the artificial lips as well as the re-designing of the artificial lips and lung mechanisms2016Inngår i: Robotics and Autonomous Systems, ISSN 0921-8890, E-ISSN 1872-793X, Vol. 86, s. 174-183Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The authors are developing anthropomorphic musical performance robots as an approach to understand the human motor control and to enhance the human-robot interaction from an engineering point of view. For this purpose; since 1990, we have developed an anthropomorphic flutist robot. As one of our long-term approaches, we aim to develop an anthropomorphic musical performance robot capable of playing different kinds of woodwind instruments, e.g. flute and saxophone. In this paper, the improvements of the mechanical design and sensing system of the Waseda Flutist Robot No. 4 Refined V (WF-4RV) are detailed. As for the sensing system, an array of sensors has been designed to detect the lip's pressure distribution. On the other hand, the lips and lung have been re-designed to enable the flutist robot to play the saxophone.

  • 335.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Takanishi, A
    Human-Friendly Robots for Entertainment and Education2012Inngår i: Service Robots and Robotics: Design and Application / [ed] Marco Ceccarelli, Heidelberg, Germany: IGI Global , 2012, s. 130-153Kapittel i bok, del av antologi (Fagfellevurdert)
  • 336.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Takanishi, Atsuo
    Waseda University.
    Anthropomorphic Musical Robots Designed to Produce Physically Embodied Expressive Music Performances2013Inngår i: Guide to Computing for Expressive Music Performance / [ed] Kirke A., Miranda, R.E., London: Springer London, 2013, s. 235-255Kapittel i bok, del av antologi (Fagfellevurdert)
  • 337.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Takanishi, Atsuo
    Waseda University.
    Human-Friendly Robots for Entertainment Purposes and Their Possible Implications2015Inngår i: Evolutionary Robotics, Organic Computing and Adaptive Ambience: Epistemological and ethical implications of technomorphic descriptions of technologies / [ed] Michael Decker, Mathias Gutmann, Julia Knifka, Berlin: LIT Verlag, 2015Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 338.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Teshome Delellegn, Teshome
    De la Rosa, Jose Pablo
    Towards developing a multipurpose assistive vehicle robot capable of providing assistance to caregivers and support to elderly people2015Inngår i: Automation Science and Engineering (CASE), 2015 IEEE International Conference on, IEEE, 2015Konferansepaper (Fagfellevurdert)
  • 339.
    Solis, Jorge
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Teshome, Teshome Delellegn
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Development of a human friendly robot vehicle for carrying-medical tools: Embodying perceptual capabilities2014Inngår i: 14th Mechatronics Forum International Conference Mechatronics, Karlstad: Karlstads universitet, 2014, s. 370-376Konferansepaper (Fagfellevurdert)
  • 340.
    Solvang, Lorena
    et al.
    Karlstads universitet, Fakulteten för humaniora och samhällsvetenskap (from 2013), Institutionen för pedagogiska studier (from 2013).
    Haglund, Jesper
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    GeoGebra in physics education2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this presentation I would like to discuss some of the implications of using dynamic mathematics software in physics education in upper secondary schools in Sweden. The topic is in harmony with EU's Improving Teacher Quality Agenda (European Commission, 2010), with the Swedish National Strategy for School Digitization, and with enhanced formulations of digitization in the upper secondary school curriculum in Sweden and probably many other countries.Is not enough just to buy computers, tablets or other digital tools in order to increase a pupils’ digital skills. You need to create a good task for the pupils. Previous studies show that the use of digital tools can help improve student outcomes by facilitating more student-active methods and student-active methods lead to better learning outcomes than more traditional methods.Mats Brunström and Maria Fahlgren at Karlstad University have worked to develop computer-based student activities where students are given the opportunity to explore, experiment and resonate in mathematics. The dynamic mathematic program they have used is GeoGebra. Introduced in 2002 GeoGebra has a fast-growing user group with its own forums and own database of applications in mathematics and adjoining areas. We want to explore the benefits of using GeoGebra even in physics education so we have initiated a study where we analyze how pupils from an upper secondary school in Sweden interact with the software. We studied an application where the pupils examine dynamic and static friction by varying the influential variables in a systematic manner. Students worked in pairs and we video recorded the students working with the task we have created for this study. In the video analysis of student interaction, we focus on how the program supports their learning.At the Conference on Education and New learning Technologies we would like to contribute by giving examples of how to use GeoGebra for dynamic visualization in mathematics and physics and exchange ideas about how the program can be used in teaching and didactic research.

  • 341.
    Solvang, Lorena
    et al.
    Karlstads universitet, Fakulteten för humaniora och samhällsvetenskap (from 2013), Institutionen för pedagogiska studier (from 2013). FUNDIG.
    Haglund, Jesper
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013). SMEER.
    Vad händer när dynamiska matematikprogram används i gymnasiefysiken?2019Inngår i: Forum för forskningsbaserad NT-undervisning: Bidrag från konferensen FobasNT18 13–14 mars 2018 i Norrköping / [ed] Karin Stolpe, Gunnar Höst och Andreas Larsson, Linköping: Linköpings universitet , 2019, s. 133-150Konferansepaper (Annet vitenskapelig)
    Abstract [sv]

    Regeringsbeslutet från oktober 2017, Läroplanen och Ämnesplanen för fysik i gymnasieskolan poängterar vikten av att inkludera digitala verktyg i undervisningen. Erfarenheter från skolan och didaktisk forskning visar att en ökad digital kompetens inte innebär att endast köpa in datorer, surfplattor eller liknande utrustning. Det krävs också bland annat att vi hittar bra exempel som kan användas i undervisningen och det krävs mer forskning kring användandet av digitala verktyg i undervisningen. GeoGebra, ett dynamiskt matematikprogram, är en möjlig sådan teknik, som har fått stor uppmärksamhet i matematikundervisningen. I denna studie utforskar vi möjligheterna att dra nytta av GeoGebra även i fysikundervisningen och undersöker elevernas lärprocesser under deras interaktion med programvaran. Den här studien fokuserar på hur gymnasieelever använder en fritt tillgänglig GeoGebra-applikation. Med hjälp av applikationen undersöker eleverna parvis dynamisk och statisk friktion då en kraft verkar på en kloss, genom att ändra påverkande variabler på ett systematiskt sätt, i linje med variationsteorin. Vid videoanalys av elevernas interaktion fokuserar vi på hur programmet stödjer deras lärande, till exempel kring förklaringar av friktion på makroskopiska och mikroskopiska nivåer.

  • 342.
    Starfelt, Samuel
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Zhang, Hanmin
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013). Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Materialvetenskap.
    Johansson, Lars
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013). Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Materialvetenskap.
    Quantum-well states in thin Ag films grown on the Ga/Si(111)-root 3 x root 3 surface2018Inngår i: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 97, nr 19, artikkel-id 195430Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Silver thin films have been created by room temperature deposition on a Ga/Si(111)-root 3 x root 3 surface and their valence band structures and core levels have been measured by angle-resolved photoelectron spectroscopy (ARPES). Discrete quantum-well states (QWSs) quantized from the Ag sp valence band are observed already at 3 monolayers (ML). The characteristics of the QWSs have been examined in the phase accumulation model for thicknesses between 3 and 12 ML. The phase shift and QWSs binding energies dependence with Ag film thicknesses have all been consistently derived. In-plane energy dispersion follows a parabolic curve, and the effective mass of the QWSs shows an increasing trend with binding energies as well as with reduced film thicknesses. Furthermore, the ARPES measurements reveal umldapp mediated QWSs around the (M)over-bar points of the Si(111) 1 x 1 surface Brillouin zone. The study confirms that the Ga/Si(111)-root 3 x root 3 surface is a good substrate for growing uniform ultrathin Ag films in room temperature conditions.

  • 343.
    Sundell, Richard
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    NTA i teknikundervisning: En studie om tekniklärares tankar om teknikämnet och NTA.2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The purpose of this study is to investigate the technology teacher attitude toward the subject of technology and link this to the use of NTA (Science and technology for all) in the primary school (graders 4-6) technical education. As Teknikforetagen (2006) stress in their report, the subject seems to be an undisclosed topic that often is combined with the science subjects. There, the science-orientating subjects get a higher priority than the technology. According to several reports, NTA has had a positive result in the teaching it is aimed at. The method of study is a qualitative survey consisting of interviews with middle school technical teachers. The interviews consisted of both technical teachers who use NTA in education and technology teachers without NTA. The result shows that NTA contributes to more practical work in technology, that teachers save time collecting materials, but also that collegial learning in technology increases. Overall, none of the interviewed teachers uses a textbook as support in the teaching. It differs from many other subjects in elementary school. The interviewed teachers generally have a positive attitude towards the subject of technology.

  • 344.
    Svensson, Anders
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Path Integral for the Hydrogen Atom: Solutions in two and three dimensions2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The path integral formulation of quantum mechanics generalizes the action principle of classical mechanics. The Feynman path integral is, roughly speaking, a sum over all possible paths that a particle can take between fixed endpoints, where each path contributes to the sum by a phase factor involving the action for the path. The resulting sum gives the probability amplitude of propagation between the two endpoints, a quantity called the propagator. Solutions of the Feynman path integral formula exist, however, only for a small number of simple systems, and modifications need to be made when dealing with more complicated systems involving singular potentials, including the Coulomb potential. We derive a generalized path integral formula, that can be used in these cases, for a quantity called the pseudo-propagator from which we obtain the fixed-energy amplitude, related to the propagator by a Fourier transform. The new path integral formula is then successfully solved for the Hydrogen atom in two and three dimensions, and we obtain integral representations for the fixed-energy amplitude.

  • 345.
    Söderström, Torsten
    et al.
    Uppsala University.
    Irshad, Yasir
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Mossberg, Magnus
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Zheng, Wei Xing
    University of Western Sydney.
    On the accuracy of a covariance matching method for continuous-time errors-in-variables identification2013Inngår i: Automatica, ISSN 0005-1098, E-ISSN 1873-2836, Vol. 49, nr 10, s. 2982-2993Artikkel i tidsskrift (Fagfellevurdert)
  • 346.
    Söderström, Torsten
    et al.
    Uppsala University.
    Mossberg, Magnus
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för fysik och elektroteknik. Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik.
    Accuracy analysis of a covariance matching approach for identifying errors-in-variables systems2011Inngår i: Automatica, ISSN 0005-1098, E-ISSN 1873-2836, Vol. 47, nr 2, s. 272-282Artikkel i tidsskrift (Fagfellevurdert)
  • 347.
    Tahaei Yaghoubi, Saba
    et al.
    Aalto University, Finland.
    Balobanov, Viacheslav
    Aalto University, Finland.
    Mousavi, Mahmoud
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Niiranen, Jarkko
    Aalto University, Finland.
    Variational formulations and isogeometric analysis for the dynamics ofanisotropic gradient-elastic Euler-Bernoulli and shear-deformable beams2018Inngår i: European journal of mechanics. A, Solids, ISSN 0997-7538, E-ISSN 1873-7285, Vol. 69, s. 113-123Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A strain and velocity gradient framework is formulated for centrosymmetric anisotropic Euler-Bernoulli and third-order shear-deformable (TSD) beam models, reducible to Timoshenko beams. The governing equations and boundary conditions are obtained by using variational approach. The strain energy is generalized to include strain gradients and the tensor of anisotropic static length scale parameters. The kinetic energy includes velocity gradients and a tensor of anisotropic length scale parameters and hence the static and kinetic quantities of centrosymmetric anisotropic materials are distinguished in micro- and macroscales. Furthermore, the external work is written in the corresponding general form. Free vibration of simply supported centrosymmetric anisotropic TSD beams is studied by using analytical solution as well as an isogeometric numerical method verified with respect to convergence.

  • 348.
    Talyzin, Alexandr V.
    et al.
    Umea Univ, Dept Phys, SE-90187 Umea, Sweden..
    Luzan, Serhiy
    Umea Univ, Dept Phys, SE-90187 Umea, Sweden..
    Anoshkin, Ilya V.
    Aalto Univ, Dept Appl Phys, FI-00076 Espoo, Finland..
    Nasibulin, Albert G.
    Aalto Univ, Dept Appl Phys, FI-00076 Espoo, Finland..
    Kauppinnen, Esko I.
    Aalto Univ, Dept Appl Phys, FI-00076 Espoo, Finland..
    Dzwilewski, Andrzej
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Kreta, Ahmed
    Natl Inst Chem, Ljubljana 1000, Slovenia..
    Jamnik, Janko
    Natl Inst Chem, Ljubljana 1000, Slovenia..
    Hassanien, Abdou
    Natl Inst Chem, Ljubljana 1000, Slovenia..
    Lundstedt, Anna
    Uppsala Univ, Dept Chem BMC, SE-75123 Uppsala, Sweden..
    Grennberg, Helena
    Uppsala Univ, Dept Chem BMC, SE-75123 Uppsala, Sweden..
    Hydrogen-Driven Cage Unzipping of C-60 into Nano-Graphenes2014Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 118, nr 12, s. 6504-6513Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Annealing of C-60 in hydrogen at temperatures above the stability limit of C H bonds in C60Hx (500-550 degrees C) is found to result in direct collapse of the cage structure, evaporation of light hydrocarbons, and formation of solid mixture composed of larger hydrocarbons and few-layered graphene sheets. Only a minor part of this mixture is soluble; this was analyzed using matrix-assisted laser desorption/ionization MS, Fourier transform infrared (FTIR), and nuclear magnetic resonance spectroscopy and found to be a rather complex mixture of hydrocarbon molecules composed of at least tens of different compounds. The sequence of most abundant peaks observed in MS, which corresponds to C2H2 mass difference, suggests a stepwise breakup of the fullerene cage into progressively smaller molecular fragments edge-terminated by hydrogen. A simple model of hydrogen-driven C-60 unzipping is proposed to explain the observed sequence of fragmentation products. The insoluble part of the product mixture consists of large planar polycyclic aromatic hydrocarbons, as evidenced by FTIR and Raman spectroscopy, and some larger sheets composed of few-layered graphene, as observed by transmission electron microscopy. Hydrogen annealing of C-60 thin films showed a thickness-dependent results with reaction products significantly different for the thinnest films compared to bulk powders. Hydrogen annealing of C-60 films with the thickness below 10 nm was found to result in formation of nanosized islands with Raman spectra very similar to the spectra of coronene oligomers and conductivity typical for graphene.

  • 349.
    Talyzin, Alexandr V.
    et al.
    Umea Univ, Dept Phys, S-90187 Umea, Sweden..
    Mercier, Guillaume
    Umea Univ, Dept Phys, S-90187 Umea, Sweden..
    Klechikov, Alexey
    Umea Univ, Dept Phys, S-90187 Umea, Sweden..
    Hedenstrom, Mattias
    Umea Univ, Dept Chem, S-90187 Umea, Sweden..
    Johnels, Dan
    Umea Univ, Dept Chem, S-90187 Umea, Sweden..
    Wei, Di
    Nokia Technol, Broers Bldg,21 II Thomson Ave, Cambridge CB3 0FA, England..
    Cotton, Darryl
    Nokia Technol, Broers Bldg,21 II Thomson Ave, Cambridge CB3 0FA, England..
    Opitz, Andreas
    Humboldt Univ, Dept Phys, D-12489 Berlin, Germany..
    Moons, Ellen
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Brodie vs Hummers graphite oxides for preparation of multi-layered materials2017Inngår i: Carbon, ISSN 0008-6223, E-ISSN 1873-3891, Vol. 115, s. 430-440Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Graphite oxides synthesized by one and two step Brodie oxidation (BGO) and Hummers (HGO) methods were analyzed by a variety of characterization methods in order to evaluate the reasons behind the difference in their properties. It is found that the Brodie method results in a higher relative amount of hydroxyl groups and a more homogeneous overall distribution of functional groups over the planar surface of the graphene oxide flakes. The higher number of carbonyl and carboxyl groups in HGO, detected by several methods, including XPS, NMR and FTIR, unavoidably results in defects of the graphene "skeleton", holes and overall disruption of the carbon-carbon bond network, stronger deviation from planar flake shape and poor ordering of the graphene oxide layers. It is also suggested that functional groups in HGO are less homogeneously distributed over the flake surface, forming some nanometer-sized graphene areas. The presence of differently oxidized areas on the GO surface results in inhomogeneous solvation and hydration of HGO and effects of inter- and intra-stratification. The proposed interpretation of the data explains the higher mechanical strength of multi-layered BGO membranes/papers, which are also less affected by humidity changes, thus providing an example of a membrane property superior to that of HGO. (C) 2016 Published by Elsevier Ltd.

  • 350.
    Thell Andreasson, Sara
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Elevers relation till teknik: En studie om vad som påverkar elever i årskurs 9 att välja ett tekniskt gymnasieprogram2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Teknik är ett ämne som lätt integreras i projekt inom skolan. Eleverna använder teknik dagligen både på sin fritid och i skolan, men trots det visar många elever ett lågt intresse för skolämnet teknik. Av den anledningen blev syftet att synliggöra vad ett teknikintresse grundar sig i och undersöka hur elever i årskurs 9 som valt ett tekniskt gymnasieprogram resonerar i sina studieval. Studien bygger på kvalitativa intervjuer med sex niondeklassare utifrån semistrukturerade frågor som utgår ifrån en modell gällande självkänsla och motivation i relation till val av aktiviteter. Resultatet visade att elevernas teknikintresse grundades i deras hemmiljö och av deras erfarenheter via teknik inom motorsport och datorer. Eleverna baserade sina gymnasieval på intresse, inre motivation och yttre påverkan, samt elevernas yttre motivation att genom utbildning erhålla en stabil inkomst. Eleverna minns knappt undervisningen på låg- och mellanstadiet och det indikerar att lärare måste bli bättre på att synliggöra teknik om elevernas intresse för teknik ska öka. 

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