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  • 101.
    Bernacka Wojcik, Iwona
    et al.
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Huerta, Miriam
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Tybrandt, Klas
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Karady, Michal
    Swedish Univ Agr Sci, Sweden.
    Mulla, Yusuf
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Poxson, David
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Gabrielsson, Erik
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Ljung, Karin
    Swedish Univ Agr Sci, Sweden.
    Simon, Daniel
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Stavrinidou, Eleni
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Implantable Organic Electronic Ion Pump Enables ABA Hormone Delivery for Control of Stomata in an Intact Tobacco Plant2019In: Small, ISSN 1613-6810, E-ISSN 1613-6829, Vol. 15, no 43, article id 1902189Article in journal (Refereed)
    Abstract [en]

    Electronic control of biological processes with bioelectronic devices holds promise for sophisticated regulation of physiology, for gaining fundamental understanding of biological systems, providing new therapeutic solutions, and digitally mediating adaptations of organisms to external factors. The organic electronic ion pump (OEIP) provides a unique means for electronically-controlled, flow-free delivery of ions, and biomolecules at cellular scale. Here, a miniaturized OEIP device based on glass capillary fibers (c-OEIP) is implanted in a biological organism. The capillary form factor at the sub-100 mu m scale of the device enables it to be implanted in soft tissue, while its hyperbranched polyelectrolyte channel and addressing protocol allows efficient delivery of a large aromatic molecule. In the first example of an implantable bioelectronic device in plants, the c-OEIP readily penetrates the leaf of an intact tobacco plant with no significant wound response (evaluated up to 24 h) and effectively delivers the hormone abscisic acid (ABA) into the leaf apoplast. OEIP-mediated delivery of ABA, the phytohormone that regulates plants tolerance to stress, induces closure of stomata, the microscopic pores in leafs epidermis that play a vital role in photosynthesis and transpiration. Efficient and localized ABA delivery reveals previously unreported kinetics of ABA-induced signal propagation.

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  • 102.
    Bernard, Christophe
    et al.
    Aix Marseille Université, INS, Marseille, France; Inserm, UMR_S 1106, Marseille, France.
    Simon, Daniel
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Malliaras, George G
    Department of Bioelectronics, Ecole Nationale Supérieure des Mines, CMP-EMSE, MOC, Gardanne, France.
    Organic Bioelectronics for Interfacing with the Brain2016In: The WSPC Reference on Organic Electronics: Organic Semiconductors: Volume 2: Fundamental Aspects of Materials and Applications / [ed] Seth R Marder, Jean-Luc Bredas, World Scientific, 2016, p. 345-368Chapter in book (Other academic)
    Abstract [en]

    Understanding how the brain works represents probably the most important fundamental endeavor of humankind and holds the key for the development of new technologies that can help improve the lives of people suffering from neurological conditions such as epilepsy and Parkinson's disease. Over the past decade, the use of organic electronic devices to interface with the biological world has received a great deal of attention and bloomed into a field now called “organic bioelectronics”. One of the key differences of organic from traditional electronic materials is their capacity to exchange ions with electrolytes. We discuss how this property can be leveraged to design new types of devices that interface with the brain.Read 

  • 103.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    A tool to see with or just something to manipulate?: Investigating engineering students’ use of oscilloscopes in the laboratory2015Conference paper (Refereed)
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  • 104.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Beyond active learning: Critical factors for learning in labs2017In: 7th Research in Engineering Education Symposium (REES 2017), Bogota, Columbia, 6-8 July 2017, Volume 2 of 2, Research In Engineering Education Network , 2017, Vol. 2, p. 532-540Conference paper (Refereed)
    Abstract [en]

    Active learning is generally defined as an approach that engages students in the learning process and is supposed to lead to consistently better and deeper understanding. In an earlier study students in mechanics were offered the choice between labs using probe-ware (MBL) [FMCE normalised gain: 48%] and experimental problem-solving labs [18% gain]. Both options were considered to employ active learning, but the difference in gains was remarkable. As this contradicts the conclusions in the literature a follow-up study was performed. Analysis of video recordings from the labs showed that in probe-ware labs students linked observed data to concepts, whereas students in the problem-solving labs made little use of physical concepts in their modeling of phenomena. One implication of this study is that we have to go beyond surface interpretations of “active learning”, and in a detailed and nuanced way look into the ways in which students are actually active in a learning environment.

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    Beyond active learning: Critical factors for learning in labs
  • 105.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Critical aspects for student learning in the physics laboratory: The role of instrumental technologies2013Conference paper (Other academic)
  • 106.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Engineering Education Research as Engineering Research2015In: International perspectives on engineering education: Engineering education and practice in context, volume 1 / [ed] Hyldgaard Christensen, Steen; Didier, Christelle; Jamison, Andrew; Meganck, Martin; Mitcham, Carl; Newberry, Byron, Cham: Springer , 2015, 1, p. 393-414Chapter in book (Refereed)
    Abstract [en]

    Engineering Education Research (EER) has recently emerged as a field of research worldwide. In this context one could focus on the conceptual difficulties experienced by engineers learning about educational research. However, in this chapter I explore the contributions that engineering and engineers can make to education research, based on the view, drawn from John Dewey’s essay “Education as engineering”, that EER could be regarded as engineering research. My first point is that engineers have learned to handle both general aspects (in the case of bridge building: engineering mathematics, solid mechanics, materials science, geology etc.) and particular aspects (the local situation of particular bridges) of their profession. Hence, it is not possible in engineering to simply apply knowledge from science to practice and Dewey points out that this also applies to education. My second point is that engineers are trained to acquire proficiency in design and both understanding and improving complex systems. Similarly, in “design-based research” or “design experiments” in education, insights from design and engineering are employed to address the complexity of educational activities and the need, as known from engineering, for theory as well as tinkering. My third point is related to the role of technologies in promoting engineering students’ learning in, for example, laboratories. Diverse technologies (artifacts) are crucial in engineering for collecting and processing data from experiments and/or real environments for numerous applications, for example controlling and monitoring production processes and monitoring the environment. Thus, engineers have high proficiency in the use of technologies and materiality, strong awareness of their impact on human perception, and hence can make valuable contributions to their application in educational contexts.

  • 107.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Engineering Education Research in Europe – coming of age: Special Issue2018Collection (editor) (Refereed)
  • 108.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Engineering Education Research in Europe: coming of age2018In: European Journal of Engineering Education, ISSN 0304-3797, E-ISSN 1469-5898, Vol. 43, no 2, p. 167-170Article in journal (Other academic)
    Abstract [en]

    n/a

  • 109.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Etablering av ingenjörsvetenskapens didaktik som ett internationellt forskningsfält – spänningar och möjligheter när forskningstraditioner möts2010Conference paper (Other academic)
  • 110.
    Bernhard, Jonte
    Linköping University, The Institute of Technology. Linköping University, Department of Science and Technology, Physics and Electronics.
    Humans, intentionality, experience and tools for learning: Some contributions from post-cognitive theories to the use of technology in physics education2007In: AIP Conf. Proc. / [ed] Leon Hsu, Charles Henderson, Laura McCullough, College Park, Maryland: AIP , 2007, Vol. 951, no 1, p. 45-48Conference paper (Refereed)
  • 111.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Improving engineering physics teaching: learning from physics education research2000In: Physics Teaching in Engineering Education (PTEE 2000), 2000Conference paper (Refereed)
    Abstract [en]

    Students come to our courses with a personal theory of physics. Most students do not change theirpersonal theories during a traditionally taught physics course. In this paper I will give some reasons forthis and also highlight some successful active-engagement curricula who help students to modify theirpersonal theories of physics and thus help them acquiring a good functional understanding of physics.

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  • 112.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Improving engineering students’ learning through the use of a variation approach: Examples from a research- based learning environment in mechanics.2010In: ReflekTori 2010 / [ed] Myller, E, Espoo: Dipoli-Reports , 2010, p. 46-56Conference paper (Refereed)
    Abstract [en]

    In this paper I describe a study wthere 25 students of a total of 111 in taking a physics course for engineering students participated in 16 hours of alternative, conceptual, labs instead of 16 hours of regular, non-conceptual, labs. All students participated in the same set of lectures and the same problem-solving sessions. A feature of the conceptual labs is the use of technology as a tool to aid students’ inquiry. In addition, systematic variation, based on the theory of variation, has been introduced into the design of the assigned tasks. Results from the a “Force and Motion Conceptual test (FMCE)” show a marked difference in achievement, with normalised gain of 48% for the students participating in the conceptual labs and 18% for the students participating in the non-conceptual labs. Some data from video-recordings of student courses of action in the conceptual labs will are also be presented.

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  • 113.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Insightful learning in the laboratory: Some experiences from ten years of designing and using conceptual labs2010In: European Journal of Engineering Education, ISSN 0304-3797, E-ISSN 1469-5898, Vol. 35, no 3, p. 271-287Article in journal (Refereed)
    Abstract [en]

    I describe a series of projects on the design and implementation of “conceptual labs” aimed atdeveloping insightful learning, following work that began in 1994/95. The main focus has been oncourses in mechanics and electric circuit theory. The approach taken in designing these innovativecurricula can be described as “design-based research”. A common feature in these learningenvironments is the use of technology as a tool to aid students’ inquiry. In addition, systematicvariation, based on the theory of variation, has been introduced into the design of the assignedtasks. Results from conceptual inventories have demonstrated the success of conceptual labs. Inthe later projects we used video recording to study students’ courses of action in labs. I describehow these studies have provided insights into conditions that are critical for learning and howthese insights have helped me and co-workers to make further improvements to learningenvironments.

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  • 114.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Investigating student learning in two activelearning labs: Not all “active” learning laboratories result inconceptual understanding2011In: 2011 ASEE Annual Conference, 2011Conference paper (Refereed)
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  • 115.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Is Engineering Education Research Engineering?2013Conference paper (Refereed)
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  • 116.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Is the same science studied or not?: A study of learning in a physics lab as a material-discursive practice2011Conference paper (Other academic)
  • 117.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Laborativ undervisning i naturvetenskap och teknik: Kritiska villkor för insiktsfullt lärande med interaktiva teknologier2008In: Resultatdialog 2008: forskning inom utbildningsvetenskap2008, Stockholm: Vetenskapsrådet , 2008, p. 18-24Chapter in book (Other academic)
  • 118.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Learning in the laboratory through technology and variation: A microanalysis of instructions and engineering students? practical achievement2011In: 1st World Engineering Education Flash Week / [ed] Jorge Bernardino and José Carlos Quadrado, 2011Conference paper (Refereed)
    Abstract [en]

    @font-face { font-family: "Times New Roman"; }p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0cm 0cm 4pt; text-align: justify; font-size: 9pt; font-family: "Times New Roman"; }table.MsoNormalTable { font-size: 10pt; font-family: "Times New Roman"; }div.Section1 { page: Section1;Mechanics, first experienced by engineering students in introductory physics courses, encompasses an important set of foundational concepts for success in engineering. However, although it has been well known for some time that acquiring a conceptual understanding of mechanics is one of the most difficult challenges faced by students, very few successful attempts to engender conceptual learning have been described in the literature. On the contrary, research has shown that most students participating in university levelcourses had not acquired a Newtonian understanding of mechanics at the end of their respective course.

    Recently I have described more than 10 years of experiences of designing and using conceptual labs in engineering education that have successfully fostered insightful learning. In the framework of the larger project I have developed labs applying variation theory in the design of task structure and using sensor-computer-technology (“probe-ware”) for collecting and displaying experimental data in real-time. In previous studies, I have shown that these labs using probe-ware can be effective in learning mechanics with normalised gains in the g≈50-60% range and with effect sizes d≈1.1, but that this technology also can be implemented in ways that lead to low achievements.

    One necessary condition for learning is that students are able to focus on the object of learning and discern its critical features. A way to establish this, according to the theory of variation developed by Marton and co-workers, is through the experience of difference (variation), rather than through the recognition of similarity. In a lab, an experiential human–instrument–world relationship is established. The technology used places some aspects of reality in the foreground, others in the background, and makes certain aspects visible that would otherwise be invisible. In labs, this can be used to bring critical features of the object of learning into the focal awareness of students and to afford variation.

    In this study, I will account for how the design of task structure according to variation theory, as well as the probe-ware technology, make the laws of force and motion visible and learnable and, especially, in the lab studied make Newton’s third law visible and learnable. I will also, as a comparison, include data from a mechanics lab that use the same probe-ware technology and deal with the same topics in mechanics, but uses a differently designed task structure. I will argue that the lower achievements on the FMCE-test in this latter case can be attributed to these differences in task structure in the lab instructions. According to my analysis, the necessary pattern of variation is not included in the design.

    I will also present a microanalysis of 15 hours collected from engineering students’ activities in a lab about impulse and collisions based on video recordings of student’s activities in a lab about impulse and collisions. The important object of learning in this lab is the development of an understanding of Newton’s third law. The approach analysing students interaction using video data is inspired by ethnomethodology  and conversation analysis, i.e. I will focus on students practical, contingent and embodied inquiry in the setting of the lab.

    I argue that my result corroborates variation theory and show this theory can be used as a ‘tool’ for designing labs as well as for analysing labs and lab instructions.  Thus my results have implications outside the domain of this study and have implications for understanding critical features for student learning in labs.

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  • 119.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Learning in the physics laboratory as a material discursive practice2012Conference paper (Other academic)
  • 120.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Learning through artifacts in engineering education2012In: Encyclopedia of the Sciences of Learning / [ed] Norbert M. Seel., New York: Springer US , 2012, p. 1983-1986Chapter in book (Other academic)
    Abstract [en]

    Over the past century, educational psychologists and researchers have posited many theories to explain how individuals learn, i.e. how they acquire, organize and deploy knowledge and skills. The 20th century can be considered the century of psychology on learning and related fields of interest (such as motivation, cognition, metacognition etc.) and it is fascinating to see the various mainstreams of learning, remembered and forgotten over the 20th century and note that basic assumptions of early theories survived several paradigm shifts of psychology and epistemology. Beyond folk psychology and its naïve theories of learning, psychological learning theories can be grouped into some basic categories, such as behaviorist learning theories, connectionist learning theories, cognitive learning theories, constructivist learning theories, and social learning theories.

    Learning theories are not limited to psychology and related fields of interest but rather we can find the topic of learning in various disciplines, such as philosophy and epistemology, education, information science, biology, and – as a result of the emergence of computer technologies – especially also in the field of computer sciences and artificial intelligence. As a consequence, machine learning struck a chord in the 1980s and became an important field of the learning sciences in general. As the learning sciences became more specialized and complex, the various fields of interest were widely spread and separated from each other; as a consequence, even presently, there is no comprehensive overview of the sciences of learning or the central theoretical concepts and vocabulary on which researchers rely. 

    The Encyclopedia of the Sciences of Learning provides an up-to-date, broad and authoritative coverage of the specific terms mostly used in the sciences of learning and its related fields, including relevant areas of instruction, pedagogy, cognitive sciences, and especially machine learning and knowledge engineering. This modern compendium will be an indispensable source of information for scientists, educators, engineers, and technical staff active in all fields of learning. More specifically, the Encyclopedia  provides fast access to the most relevant theoretical terms provides up-to-date, broad and authoritative coverage of the most important theories within the various fields of the learning sciences and adjacent sciences and communication technologies; supplies clear and precise explanations of the theoretical terms, cross-references to related entries and up-to-date references to important research and publications. The Encyclopedia also contains biographical entries of individuals who have substantially contributed to the sciences of learning; the entries are written by a distinguished panel of researchers in the various fields of the learning sciences.

  • 121.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics.
    Learning through artifacts in engineering education: Some perspectives from the philosophy of technology and engineering science2009In: Proceedings of SEFI 37th Annual Conference: July 1-4, 2009, Rotterdam, 2009Conference paper (Refereed)
    Abstract [en]

    The concept of mediation could be represented by: Human ⇔ Mediating tools ⇔ World. Questions about the role of technology (artifacts) in everyday human experience include: How do technological artifacts affect the existence of humans and their relationship with the world? How do artifacts create and transform human knowledge? How is human knowledge incorporated into artifacts? What are the actions of artifacts? Tools (i.e. conceptual and physical artifacts) play an important role in human thinking and learning. However the role of technology is frequently missing, or insufficiently evaluated, in educational analysis. Herein, I reflect on Dewey’s notion of “education as engineering”. Considering the importance of the use of tools in education, I claim that education could, in one sense, be seen as an engineering science. Engineers are trained in design, especially in artifact design, and in under¬standing and improving complex systems. They should be trained to understand that humans are also part of the systems that they work with. Thus, approaches and knowledge from the perspective of engineering science and the philosophy of technology can contribute to the understanding and development of engineering education.

  • 122.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Teaching engineering mechanics courses using active engagement methods2000In: Physics Teaching in Engineering Education (PTEE 2000), / [ed] Pal Pacher, 2000Conference paper (Refereed)
    Abstract [en]

    Microcomputer based laboratories (MBL) have successfully been used to promote conceptual changein mechanics. In MBL-labs students do real experiments and taking advantage of the real-time displayof the experimental results facilitates conceptual change by the computer. Thus students’ alternativeconceptions can successfully be addressed.

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  • 123.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    The same physics studied or not?: A study of the role of technology and the ‘enacted’ and the ‘lived’ ‘object of learning’ in three different lab setups.2010Conference paper (Other academic)
    Abstract [en]

    One necessary condition for learning is that students are able to focus on the object of learning and discern its critical features. According to Marton and Pang (2008, p. 538) “‘new’ phenomenography … [also] involves the study of variation … among the critical aspects of the phenomenon as experienced or seen by the experiencer”. However as pointed out by for example Bohr (1958, p. 27) “it is … impossible to distinguish sharply between the phenomena themselves and their conscious perception”. Bohr continues (p. 73) ”it is indeed more appropriate to use the word phenomenon to refer only to observations obtained under circumstances whose description includes an account of the whole experimental arrangement”. Prior research has shown that it is difficult for most students, even at university level, to discern and learn to use motion concepts such as velocity and acceleration. Many students believe that the acceleration always is in the direction of motion and that zero velocity implies zero acceleration. Motion of an object on an inclined plane is commonly studied in physics teaching laboratories and in this study three different common physical setups are studied. It is shown that the differences led to the establishment of different experiential human–instrument–world relationship due to the differences in instrumentation. It is shown that the technology in some setups does not afford critical variation and discernment and hence the ‘enacted objects of learning’ are different although on the surface the same physics is studied. Indeed students ‘lived object of learning’ is different in the different set-ups as shown in their activities during the labs recorded by video. I conclude that my study supports variation theory, but I also argue that the role of the technology cannot be neglected.

  • 124.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Time as an example of the dialectic relationship between concepts and artefacts2012Conference paper (Other academic)
  • 125.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Tools to see with: Investigating the role of experimental technologies for student learning in the laboratory2014Conference paper (Refereed)
    Abstract [en]

    BACKGROUND: Students’ experience of the world in the laboratory is not a direct experience, human – world, but a mediated experience, human – tool – world, shaped by the use of physical and symbolic tools. Technology is used as agencies of observations, i.e. as tools for collection and processing of physical data. However, the role of experimental technologies for student learning in the laboratory is largely neglected in educational research. If technologies are studied at all, it is often seen as being synonymous with studying the role of computers.

    METHODS: Students’ interaction in different physics and electric circuit labs, with different experimental technologies, was recorded using digital camcorders. The videotaped data were used to detect typical interactional patterns. Particularly interesting parts of these sessions were transcribed to allow for detailed examination of interactional patterns.

    RESULTS: In some cases the technologies were used as tools to see the world with and some aspects of the world were put in the foreground. In other cases the technology in itself become the focus of attention and no, or inadequate, connection to the world was made. The role of the technology for students’ learning depended in some cases on the affordances of the technology used, but in other cases it depended on the pedagogical design.  

    CONCLUSION: Some experimental technologies are more effective for facilitating learning by being effective tools to see with. However, for the effective use of technologies the educational design is important and no technology is effective independently of the pedagogy used.

  • 126.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    What matters for students learning in the laboratory? Do not neglect the role of experimental equipment!2018In: Instructional science, ISSN 0020-4277, E-ISSN 1573-1952, Vol. 46, no 6, p. 819-846Article in journal (Refereed)
    Abstract [en]

    According to variation theory, it is essential to enable students to focus on the object of learning and discern its critical features, but the features that it is possible to discern often depend on the equipment used. Thus, in labs, the experimental technologies used may shape students experience of focal phenomena, in a human-mediating tools-world manner, by placing some aspects of reality in the foreground, others in the background, and visualizing certain aspects that would otherwise be invisible. However, this mediating role is often neglected, and instruments and devices are often seen as having little cognitive value. Hence, the role of experimental technologies in labs as tools for learning is examined here through a case study, in which three sets of students investigated the same physical relationships (Newtonian motion in an inclined plane), but using different measurement technologies. The results demonstrate that what it is possible for students to experience in a laboratory is heavily influenced by the chosen technology. Some technologies do not afford the discernment of features regarded as crucial for students to learn. Furthermore, analysis of video recordings shows that the three sets of students discourses differed, although they studied the "same physics". Hence, the role of experimental technologies in students learning in labs should not be neglected, and their courses of action should be seen as material-discursive practice. Moreover, general conclusions about learning in labs should be drawn cautiously, specifying the conditions and technology used, and discussions about learning technologies should not be limited to the use of computers.

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  • 127.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    What matters?: Learning in the laboratory as a material-discursive-practice2013Conference paper (Other academic)
  • 128.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Baillie, Caroline
    University of Western Australia, Australia.
    Standards for Quality of Research in Engineering Education2016In: International Journal of Engineering ,Science and Innovative Technology, ISSN 0949-149X, E-ISSN 2277-3754, International journal of engineering education, ISSN 0949-149X, Vol. 32, no 6, p. 2378-2394Article in journal (Refereed)
    Abstract [en]

    The understanding of quality in scientific work is fundamental and determines what researchers judge to represent reliable knowledge in their field. Although quality criteria are used daily in research, there are few extensive discussions available especially in Engineering Education Research (EER). For the development of future high-quality research in EER we argue that it is necessary that the EER-community begin to negotiate criteria for quality. In this paper we propose tentative criteria with a special focus on qualitative EER, although we argue that several of our proposed criteria are also appropriate for quantitative EER. Our proposed criteria are divided into three main categories: quality of a study in general, quality of the results and validity of the results. We describe these in detail, together with a number of subcategories for each and introduce a hypothetical study to exemplify our criteria. It is stressed that the proposed criteria are tentative and that criteria need to be open for debate and need to evolve as research evolves.

  • 129.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Baillie, Caroline
    University of Western Australia.
    Standards for quality of research in engineering education2013Conference paper (Refereed)
    Abstract [en]

    The conception of quality in scientific work is fundamental and determines what researchers judge as reliable knowledge in their field. Although criteria of quality is used daily in research there are few extensive reviews available especially in Engineering Education Research (EER). For the development of high-quality research in EER in the future we argue that it is necessary that the EER-community begin to negotiate criteria for quality. In our reflection we consider: quality of a study in general, quality of the results and validity of the results.

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  • 130.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Baillie, Caroline
    University of Western Australia.
    Standards for quality of research in engineering education: A prologomenon2012In: Engineering education 2020: Meet the future / [ed] Aris Avdelas, Thessaloniki: Aristotle University of Thessaloniki , 2012Conference paper (Refereed)
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  • 131.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Carstensen, Anna-Karin
    Jönköping University, Jönköping, Sweden.
    Analysing and modelling engineering students’ learning in the laboratory: a comparison of two methodologies2015In: Proceedings of 6th Research in Engineering Education Symposium (REES 2015): Translating Research into Practice, 2015, p. 620-628Conference paper (Refereed)
    Abstract [en]

    Producing structured, meaningful and useful descriptions (representations) of students’ learning in labs is not straightforward. Two possible approaches are compared here. Students’ courses of action in labs of an electric circuit course were video-recorded, then the activities during the labs were described and analysed using “the learning of a complex concept” (LCC) methodology. Conversations during the full lengths of the same labs were also transcribed verbatim. Subsequent analysis indicates that transcription offers a more detailed representation of the learning and interaction that occurred. However, it is considerably slower than LCC methodology, which can also represent learning in the full length of a lab in some detail. Furthermore, the latter gave a better overview of the analysed labs than transcription and more readily facilitated representation of both learning complexities and linking theory to practice. In conclusion, both methods can play valuable roles in engineering education research, depending on the questions addressed.

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  • 132.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Carstensen, Anna-Karin
    School of Engineering, Jönköping University Jönköping, Sweden.
    “Real” experiments or computers in labs – opposites or synergies?: Experiences from a course in electric circuit theory2017In: Proceedingsof the 45th SEFI Annual Conference 2017 Education Excellence for Sustainability: Education Excellence for Sustainability / [ed] José Carlos Quadrado, Jorge Bernardino, João Rocha, Bryssels: SEFI – Société Européenne pour la Formation des Ingénieurs , 2017, p. 1300-1307Conference paper (Refereed)
    Abstract [en]

    In this study we report from our experiences designing and re-designing a lab where engineering students studied transient response in electric circuits. In the first version of the lab students had difficulties doing the mathematical modeling of the experimentally measured graphs as it required students’ to link the time- and frequency domains as well as the object/event and theory/model worlds simultaneously. In the re-designed lab some computer simulations were included together with the original experiments on real circuits. The simulations opened up for learning and enabled students to establish links that are hard access directly with real experiments.Still doing real experiments is important to secure students ability to make links between models and theories and the physical reality. This study demonstrates that synergetic learning effects can be achieved by a careful design using an insightful combination of real experiments and computer simulations.  Hence, we propose that the question of “real” experiments or “virtual” labs using computer simulations are best for students’ learning is not an either or question. Rather, it is a question of finding the right blend to achieve synergetic effects.

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    “Real” experiments or computers in labs – opposites or synergies?: Experiences from a course in electric circuit theory
  • 133.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics.
    Carstensen, Anna-Karin
    “Real” Experiments or Simulated Experiments in Labs – Opposites or Synergies?: Experiences from a Course in Electric Circuit Theory2017In: Proceedings från 6:e UTVECKLINGSKONFERENSEN för Sveriges ingenjörsutbildningar / [ed] Lena Peterson, Kristina Edström, Oskar Gedda,Fredrik Georgsson, Liselott Lycke och Marie Arehag, 2017Conference paper (Refereed)
    Abstract [en]

    ——“Are simulations or ‘real’ labs better for students’ learning?” is frequently discussed. Often positions in this debate are phrased in either or terms. In this study we report from a re-design of a lab where computer simulations were included together with experiments on real circuits in a transient response lab in an electric circuit theory course. In the first version of the lab students had difficulties doing the mathematical modeling of the experimentally measured graphs as it required students’ to link the time- and frequency domains as well as the object/event and theory/model worlds simultaneously. The inclusion of computer simulations as an addition to real experiments in the re-designed lab opened up for learning and enabled students to establish links that were impossible to access directly with real experiments. Still doing real experiments is important to secure students ability to make links between models and theories and the physical reality. This study demonstrates that synergetic learning effects can be achieved by a careful design using an insightful combination of real experiments and computer simulations.  Hence, we propose that the question of “real” experiments or “virtual” labs using computer simulations are being best for students’ learning is not an either or question. Rather, it is a question of finding the right blend of carefully designed learning activities to achieve synergetic effects.

  • 134.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Carstensen, Anna-Karin
    Högskolan i Jönköping.
    Studier av lärande inom ingenjörsvetenskap och "techno-science" som en materiell diskursiv praktik2015In: Resultatdialog 2015 / [ed] Petter Aasen och Eva Björck, Stockholm: Vetenskapsrådet , 2015, p. 42-55Chapter in book (Other academic)
    Abstract [sv]

    Inom såväl ingenjörs- som naturvetenskap är experimentell verksamhet central och olika instrumentella tekniker såsom oscilloskop, mikroskop, röntgenapparater och andra sensorer används som medierande verktyg för att erfara världen med. Laborationer är ett centralt inslag i undervisningen i dessa ämnen. Vi visar i våra studier att instrumentering och andra teknologier som används i samband med laborationer inte är neutrala tekniker. Sådana teknologier kan ha kognitivt värde genom att de erbjuder möjligheter till urskiljande och fokusering, det vill säga ger möjligheter att utforma laborationer där kritiska aspekter i ämnesinnehållet kan urskiljas vilket ger goda läranderesultat. Lärandet under en laboration måste därmed analyseras med hänsyn till såväl de fysiska verktyg (artefakter) såsom olika mätinstrument, mätsystem och system för bearbetning och visualisering av experimentella data som de symboliska verktyg i form av modeller, begrepp och representationer som studenter använder.

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    Studier av lärande inom ingenjörsvetenskap och "techno-science" som en materiell diskursiv praktik
  • 135.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Carstensen, Anna-Karin
    Ingenjörshögskolan, Högskolan i Jönköping.
    Holmberg, Margarita
    ESIME, Instituto Politéchnico Nacional, Mexico City.
    Investigating the model 'learning of a complex concept': The process of learning in a course in electric circuits2009In: Proceeding of the SEFI Conference Physics Teaching in Engineering Education: 10-12 September, 2009, Wroclaw., Wroclaw, 2009, p. 141-146Conference paper (Refereed)
    Abstract [en]

    We have studied engineering students’ learning in an electric circuit theory course using the model learning of a complex concept as an analytic tool. A complex concept is a whole that is made up of “single” interrelated “concepts”. Student learning is analysed by studying the links students make between these “single concepts”. The more links that are made by students, the more complete their knowledge becomes.

  • 136.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Carstensen, Anna-Karin
    Ingenjörshögskolan, Jönköping, Sweden.
    Holmberg (née Gonzalez-Sampayo), Margarita
    ESIME, Instituto Politechnico Nacional, Mexico City, Mexico.
    Analytical tools in engineering education research: The “learning a complex concept” model, threshold concepts and key concepts in understanding and designing for student learning2011In: Research in Engineering Education Symposium, 2011, Madrid: Universidad Politécnica de Madrid (UPM) , 2011, p. 51-60Conference paper (Refereed)
    Abstract [en]

    For a long time, most research relating to science and engineering education has examined “misconceptions” about “single concepts”, despite the fact that one common objective in many subjects is “to learn relationships”. In this paper we introduce the notion of “a complex concept”, i.e. the idea of describing knowledge as a complex, a holistic unit, consisting of interdependent and interrelated “single concepts”. We describe how this conception could be used to identify both problems associated with learning as well potentials for learning. We will also relate the notion of a complex concept to the notion of threshold and key concepts.

  • 137.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Carstensen, Anna-Karin
    Ingenjörshögskolan, Jönköping, Sweden.
    Holmberg (née Gonzalez-Sampayo), Margarita
    ESIME, Instituto Politechnico Nacional, Mexico City, Mexico.
    Beyond simplistic conceptual change: Learning electric circuit theory as the ”learning of a complex concept”2012Conference paper (Other academic)
  • 138.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Carstensen, Anna-Karin
    Ingenjörshögskolan, Jönköping.
    Holmberg (née Gonzalez-Sampayo), Margarita
    ESIME, Instituto Politechnico Nacional, Mexico City.
    Investigating engineering students‘ learning – learning as the learning of a complex concept2010In: Proceedings of the Joint International IGIP-SEFI Annual Conference 2010, 2010Conference paper (Refereed)
    Abstract [en]

    In both engineering and physics education, a common objective is that students should learn to use theories and models in order to understand the relation between theories and models, and objects and events, and to develop holistic, conceptual knowledge. During lab-work, students are expected to use, or learn to use, symbolic and physical tools (such as concepts, theories, models, representations, inscriptions, mathematics, instruments and devices) in order both to understand the phenomena being studied, and to develop the skills and abilities to use the tools themselves. We have earlier argued that this learning should be seen as the learning of a complex concept, i.e. a “concept” that makes up a holistic system of “single” interrelated “concepts” (i.e. a whole made up of interrelated parts). On the contrary, however, in education research it is common to investigate “misconceptions” of “single concepts”. In this paper we will show the power of analysing engineering students’ learning as the learning of a complex concept. In this model “single concepts” are illustrated as nodes or “islands” that may be connected by links, while the links that students actually make are represented by arrows. The nodes in our model are found by looking for “gaps” in the actions and conversations of students. A gap corre­sponds to a non-established link, and when a gap is filled and the students establish a relation between two nodes, this is represented by a link. The more links that are made, the more complete the knowledge. In this study we report an analysis of a sequence of labs about AC-electricity in an electric circuit theory course. In for example electric circuit theory the “concepts” of current, voltage and impedance are interdependent. Rather, the central physical phenomenon is “electricity” represented by Ohms law as a generalization of the current/voltage/impedance/frequency-relationship of a circuit or circuit element. The results show the learning of “electricity” as a complex concept with students’ knowledge becoming more complete. Furthermore, according to our analysis “entities” that in later labs were fused into one were separate in the earlier labs. For example in a later lab we could note that “the physical circuit” and “the circuit drawing” had fused into a single “real circuit”. Our results suggest that the learning of a complex concept first start with establishing more and more links. As links become well established, “entities” that have been separate fuse into a whole. Our model suggests a method for finding “learning difficulties” since these corresponds to “gaps” and non-established links. As teachers and experts in a field we can miss to uncover these since for us the ‘complex concept’ has become a conceptual whole and we may no longer be able to distinguish the parts in the complex. In line with the thesis of M. Holmberg we also argue that learning problems in electric circuit theory may be due to the common failure to appreciate that concepts are relations.

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  • 139.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Carstensen, Anna-Karin
    Ingenjörshögskolan, Jönköping, Sweden.
    Holmberg (née Gonzalez-Sampayo), Margarita
    ESIME, Instituto Politechnico Nacional, Mexico City, Mexico.
    Understanding phase as a key concept in physics and electrical engineering2013Conference paper (Other academic)
    Abstract [en]

    In electrical engineering as well as in physics it is crucial to understand that the phase, and not only magnitudes, of signals such as AC-currents and voltages or light matters. In a preliminary study (Bernhard & Carstensen, 2002) we found difficulties in understanding phase relationships (cf. Kautz, 2011; Mazzolini, Scott, & Edwards, 2012) and in modeling (cf. Carstensen & Bernhard, 2008; Foley, 2010). In electrical engineering and in physics complex numbers open up for “new and previously inaccessible way of thinking” and representing phase relationships and in an earlier work we have shown that understanding complex numbers opens up for “seeing things in a new way” (Bernhard, Carstensen, & Holmberg, 2008). In this paper we will present a study using questionnaires and interviews with second and third year electrical engineering that shows that for most students phase relationships and the use of complex numbers (phasors) in representing signals still are troublesome knowledge and that most students are in a liminal space. Without understanding the concept of phase students would face immense problems in understanding for example electric circuits or optics.

  • 140.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Carstensen, Anna-Karin
    Ingenjörshögskolan, Jönköping, Sweden.
    Holmberg (née Gonzalez-Sampayo), Margarita
    ESIME, Instituto Politechnico Nacional, Mexico City, Mexico.
    Understanding phase as an entrance to the portal of understanding in physics and electrical engineering2012Conference paper (Other academic)
  • 141.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Carstensen, Anna-Karin
    Jönköping University, Sweden.
    Holmberg (née González Sampayo), Margarita
    Instituto Politécnico Nacional, Mexico City, Mexico.
    Understanding phase as a key concept in physics and electrical engineering2013Conference paper (Refereed)
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  • 142.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Carstensen, Anna-Karin
    Jönköping University, Jönköping, Sweden.
    Karlsson, Kjell
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Alternating currents first: Experiences from designing a novel approach to teaching electric circuit theory2016In: 44th SEFI Annual Conference,“Engineering Education on Top of the World: Industry-University Cooperation”, European Society for Engineering Education (SEFI) , 2016Conference paper (Refereed)
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  • 143.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics.
    Davidsen, Jacob
    Aalborg universitet.
    Ryberg, Thomas
    Aalborg universitet.
    Carstensen, Anna-Karin
    Rafn Abildgaard, Julie
    Aalborg universitet.
    Engineering students’ shared experiences and joint problem solving in collaborative learning2018In: Proceedingsof the 46th SEFI Annual Conference 2018: Creativity, Innovation and Entrepreneurship for Engineering Education Excellence / [ed] Robin Clark, Peter Munkebo Hussmann, Hannu-Matti Järvinen, Mike Murphy & Martin Etchells Vigild, Brussels, 2018, p. 597-604Conference paper (Refereed)
  • 144.
    Bernhard, Jonte
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Edström, Kristina
    KTH Royal Institute of Technology, School of Education and Communication in Engineering Science.
    Kolmos, Anette
    KTH Royal Institute of Technology, School of Education and Communication in Engineering Science /Ålborg universitet.
    Learning through design-implement experiences: A literature review2016Conference paper (Other academic)
    Abstract [en]

    In this paper we introduce some literature relevant for design-based learning, in particular for design-implement experiences in line with CDIO Standard 5. The aim is to inform the development of such learning experiences and to indicate some areas where new research would be of relevance to educators.

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  • 145.
    Berto, Marcello
    et al.
    University of Modena and Reggio Emilia, Italy.
    Casalini, Stefano
    University of Modena and Reggio Emilia, Italy; Institute Ciencia Mat Barcelona ICMAB CSIC, Spain.
    Di Lauro, Michele
    University of Modena and Reggio Emilia, Italy.
    Marasso, Simone L.
    Politecn Torino, Italy; IMEM CNR, Italy.
    Cocuzza, Matteo
    Politecn Torino, Italy; IMEM CNR, Italy.
    Perrone, Denis
    Ist Italiano Tecnol, Italy.
    Pinti, Marcello
    University of Modena and Reggio Emilia, Italy.
    Cossarizza, Andrea
    University of Modena and Reggio Emilia, Italy.
    Pirri, Candido F.
    Politecn Torino, Italy; Ist Italiano Tecnol, Italy.
    Simon, Daniel
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Zerbetto, Francesco
    University of Bologna, Italy.
    Bortolotti, Carlo A.
    University of Modena and Reggio Emilia, Italy.
    Biscarini, Fabio
    University of Modena and Reggio Emilia, Italy.
    Biorecognition in Organic Field Effect Transistors Biosensors: The Role of the Density of States of the Organic Semiconductor2016In: ANALYTICAL CHEMISTRY, ISSN 0003-2700, Vol. 88, no 24, p. 12330-12338Article in journal (Refereed)
    Abstract [en]

    Biorecognition is a central event in biological processes in the living systems that is also widely exploited in technological and health applications. We demonstrate that the Electrolyte Gated Organic Field Effect Transistor (EGOFET) is an ultrasensitive and specific device that allows us to quantitatively assess the thermodynamics of biomolecular recognition between a human antibody and its antigen, namely, the inflammatory cytokine TNF alpha at the solid/liquid interface. The EGOFET biosensor exhibits a superexponential response at TNF alpha concentration below 1 nM with a minimum detection level of 100 pM. The sensitivity of the device depends on the analyte concentration, reaching a maximum in the range of clinically relevant TNF alpha concentrations when the EGOFET is operated in the subthreshold regime. At concentrations greater than 1 nM the response scales linearly with the concentration. The sensitivity and the dynamic range are both modulated by the gate voltage. These results are explained by establishing the correlation between the sensitivity and the density of states (DOS) of the organic semiconductor. Then, the superexponential response arises from the energy-dependence of the tail of the DOS of the HOMO level. From the gate voltage-dependent response, we extract the binding constant, as well as the changes of the surface charge and the effective capacitance accompanying biorecognition at the electrode surface. Finally, we demonstrate the detection of TNF alpha in human-plasma derived samples as an example for point-of-care application.

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  • 146.
    Bhaskar Gudey, Bala
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Kane, Jacob
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Co-Design of Antenna and LNA for 1.7 - 2.7 GHz2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In a radio frequency (RF) system, the front-end of a radio receiver consists of an active antenna arrangement with a conducting mode antenna along with an active circuit. This arrangement helps avoid losses and SNR degradation due to the use of a coaxial cable. The active circuit is essentially an impedance matching network and a low noise amplification (LNA) stage. The input impedance of the antenna is always different from the source impedance required to be presented at the LNA input for maximum power gain and this gives rise to undesired reflections at the antenna-LNA junction. This necessitates a matching network that provides the impedance matching between the antenna and the LNA at a central frequency (CF). From the Friis formula it is seen that the total noise figure (NF) of the system is dependent on the noise figure and gain of the first stage. So, by having an LNA that provides a high gain (typically >15 dB) which inserts minimum possible noise (desirably < 1 dB), the overall noise figure of the system can be maintained low. The LNA amplifies the signal to a suitable power level that will enable the subsequent demodulation and decoding stages to efficiently recover the original signal. The antenna and the LNA can be matched with each other in two possible ways. The first approach is the traditional method followed in RF engineering where in both the antenna and LNA are matched to 50 Ω terminations and connected to each other. In this classical method, the antenna and LNA are matched to 50 Ω at the CF and does not take into account the matching at other frequencies in the operation range. The second approach employs a co-design method to match the antenna and LNA without a matching network or with minimum possible components for matching. This is accomplished by varying one or more parameters of either the antenna or LNA to control the impedances and ultimately achieve a matching over a substantial range of frequencies instead at the CF alone. The co-design method is shown to provide higher gain and a lower NF with reduced number of components, cost and size as compared to the classical method.

    The thesis work presented here is a study, design and manufacturing of an antenna-LNA module for a wide frequency range of 1.7 GHz – 2.7 GHz to explore the gain and NF improvements in the co-design approach. Planar micro strip patch antennas and GaAs E-pHEMT transistor based LNA’s are designed and the matching and co-design are simulated to test the gain and NF improvements. Furthermore, fully functional prototypes are developed with Roger R04360 substrate and the results from simulations and actual measurements are compared and discussed

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  • 147.
    Blaudeck, Thomas
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Andersson Ersman, Peter
    Acreo AB, Sweden .
    Sandberg, Mats
    Acreo AB, Sweden .
    Heinz, Sebastian
    Technical University of Chemnitz, Germany .
    Laiho, Ari
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Liu, Jiang
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Engquist, Isak
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Baumann, Reinhard R.
    Technical University of Chemnitz, Germany Fraunhofer Institute Elect Nanosyst ENAS, Germany .
    Simplified Large-Area Manufacturing of Organic Electrochemical Transistors Combining Printing and a Self-Aligning Laser Ablation Step2012In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 22, no 14, p. 2939-2948Article in journal (Refereed)
    Abstract [en]

    A hybrid manufacturing approach for organic electrochemical transistors (OECTs) on flexible substrates is reported. The technology is based on conventional and digital printing (screen and inkjet printing), laser processing, and post-press technologies. A careful selection of the conductive, dielectric, and semiconductor materials with respect to their optical properties enables a self-aligning pattern formation which results in a significant reduction of the usual registration problems during manufacturing. For the prototype OECTs, based on this technology, on/off ratios up to 600 and switching times of 100 milliseconds at gate voltages in the range of 1 V were obtained.

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  • 148.
    Bohlin, Henrik
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Development of a FPGA-based development platform for real-time control of combustion engine parameters2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Today’s increased regulatory demands on emissions and hard competition drives manufacturers of heavy vehicles to try new technologies in an attempt to fulfill regulations and get ahead of competitors. This paper describes the development of a platform that is to be used as a tool to evaluate the possibilities of incorporating an FPGA in the future ECUs of Scania CV AB. Requirements for such a platform are examined and presented. These requirements are then implemented as a technology demonstrator able to sample signals from sensors and performing computations using the sampled data. The technology demonstrator is also equipped with an interface to which current ECUs can be connected.

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  • 149.
    Bondarevs, Andrejs
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Huss, Patrik
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Gong, Shaofang
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Weister, Ola
    Vertical Plants System Sweden AB.
    Liljedahl, Roger
    Vertical Plants System Sweden AB.
    Green walls utilizing Internet of Thing2015In: Sensors & Transducers Journal, ISSN 2306-8515, E-ISSN 1726-5479, Vol. 192, no 9, p. 16-21Article in journal (Refereed)
    Abstract [en]

    A wireless sensor network was used to automatically control the life-support equipment of a green wall and to measure its influence on the air quality. Temperature, relative humidity, particulate matter, volatile organic compound and carbon dioxide were monitored during different tests. Green wall performance on improving the air quality and the influence of the air flow through the green wall on its performance were studied. The experimental results show that the green wall is effective to absorb particulate matter and volatile organic compound. The air flow through the green wall significantly increases the performance. The built-in fan increases the absorption rate of particulate matter by 8 times and that of formaldehyde by 3 times.

  • 150.
    Bondarevs, Andrejs
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Huss, Patrik
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Ye, Qin-Zhong
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Gong, Shaofang
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Universal Internet of Things Solution: Protocol Independent2017In: 2017 IEEE INTERNATIONAL CONFERENCE ON INDUSTRIAL TECHNOLOGY (ICIT), IEEE , 2017, p. 1313-1318Conference paper (Refereed)
    Abstract [en]

    The diversity of wireless networks and protocols used by Internet of Things makes solutions non-interoperable. Moreover, some Things are not always able to communicate due to resource constrains or environmental factors. In this paper, those issues are addressed by introducing the concept of virtual Things. It means that each real Thing is virtualized in a local server or in the cloud, enabling communication with the user through a common protocol, i.e., the Internet Protocol. The virtual Thing has its own Internet Protocol address and authentication measure to control the access.

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