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  • 101.
    Ahrenberg, Lars
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Tekniska fakulteten.
    Swedish prepositions are not pure function words2017Inngår i: Proceedings of the NoDaLiDa 2017 Workshop on Universal Dependencies, 22 May, Gothenburg, Sweden / [ed] Marie-Catherine de Marneffe, Joakim Nivre, and Sebastian Schuster, Linköping: Linköping University Electronic Press, 2017, Vol. 135, s. 11-18Konferansepaper (Fagfellevurdert)
    Abstract [en]

    As for any categorial scheme used for annotation, UD abound with borderline cases. The main instruments to resolve them are the UD design principles and, of course, the linguistic facts of the matter. UD makes a fundamental distinction between content words and function words, and a, perhaps less fundamental, distinction between pure function words and the rest. It has been suggested that adpositions are to be included among the pure function words. In this paper I discuss the case of prepositions in Swedish and related languages in the light of these distinctions. It relates to a more general problem: How should we resolve cases where the linguistic intuitions and UD design principles are in conflict?

  • 102.
    Ahrenberg, Lars
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Tekniska fakulteten.
    Towards a research infrastructure for translation studies.2014Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    In principle the CLARIN research infrastructure provides a good environment to support research on translation. In reality, the progress within CLARIN in this area seems to be fairly slow. In this paper I will give examples of the resources currently available, and suggest what is needed to achieve a relevant research infrastructure for translation studies. Also, I argue that translation studies has more to gain from language technology, and statistical machine translation in particular, than what is generally assumed, and give some examples.

  • 103.
    Ahrenberg, Lars
    et al.
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Tekniska fakulteten.
    Tarvi, Ljuba
    Helsinki University.
    Translation Class Instruction as Collaboration in the Act of Translation2014Inngår i: Proceedings of The 9th Workshop on Innovative Use of NLP for Building Educational Applications, Baltimore, USA, June 26th, 2014. / [ed] Joel Tetreault, Jill Burstein, Claudia Leacock, The Association for Computational Linguistics , 2014, s. 34-42Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The paper offers an effective way of teacher-student computer-based collabo-ration in translation class. We show how a quantitative-qualitative method of analysis supported by word alignment technology can be applied to student translations for use in the classroom. The combined use of natural-language pro-cessing and manual techniques enables students to ‘co-emerge’ during highly motivated collaborative sessions. Within the advocated approach, students are pro-active seekers for a better translation (grade) in a teacher-centered computer-based peer-assisted translation class.

  • 104.
    Ahrén, Maria
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska högskolan.
    Selegård, Linnéa
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska högskolan.
    Klasson, Anna
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet.
    Söderlind, Fredrik
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska högskolan.
    Abrikossova, Natalia
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska högskolan.
    Skoglund, Caroline
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Bengtsson, Torbjörn
    Linköpings universitet, Institutionen för medicin och hälsa, Avdelningen för läkemedelsforskning. Linköpings universitet, Tekniska högskolan.
    Engström, Maria
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet.
    Käll, Per-Olov
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska högskolan.
    Uvdal, Kajsa
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska högskolan.
    Synthesis and Characterization of PEGylated Gd2O3 Nanoparticles for MRI Contrast Enhancement2010Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 26, nr 8, s. 5753-5762Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Recently, much attention has been given to the development of biofunctionalized nanoparticles with magnetic properties for novel biomedical imaging. Guided, smart, targeting nanoparticulate magnetic resonance imaging (MRI) contrast agents inducing high MRI signal will be valuable tools for future tissue specific imaging and investigation of molecular and cellular events. In this study, we report a new design of functionalized ultrasmall rare earth based nanoparticles to be used as a positive contrast agent in MRI. The relaxivity is compared to commercially available Gd based chelates. The synthesis, PEGylation, and dialysis of small (3−5 nm) gadolinium oxide (DEG-Gd2O3) nanoparticles are presented. The chemical and physical properties of the nanomaterial were investigated with Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, and dynamic light scattering. Neutrophil activation after exposure to this nanomaterial was studied by means of fluorescence microscopy. The proton relaxation times as a function of dialysis time and functionalization were measured at 1.5 T. A capping procedure introducing stabilizing properties was designed and verified, and the dialysis effects were evaluated. A higher proton relaxivity was obtained for as-synthesized diethylene glycol (DEG)-Gd2O3 nanoparticles compared to commercial Gd-DTPA. A slight decrease of the relaxivity for as-synthesized DEG-Gd2O3 nanoparticles as a function of dialysis time was observed. The results for functionalized nanoparticles showed a considerable relaxivity increase for particles dialyzed extensively with r1 and r2 values approximately 4 times the corresponding values for Gd-DTPA. The microscopy study showed that PEGylated nanoparticles do not activate neutrophils in contrast to uncapped Gd2O3. Finally, the nanoparticles are equipped with Rhodamine to show that our PEGylated nanoparticles are available for further coupling chemistry, and thus prepared for targeting purposes. The long term goal is to design a powerful, directed contrast agent for MRI examinations with specific targeting possibilities and with properties inducing local contrast, that is, an extremely high MR signal at the cellular and molecular level.

  • 105.
    Ahrén, Maria
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Selegård, Linnéa
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Söderlind, Fredrik
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Nanostrukturerade material. Linköpings universitet, Tekniska högskolan.
    Linares, Mathieu
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Beräkningsfysik. Linköpings universitet, Tekniska högskolan.
    Kauczor, Joanna
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Beräkningsfysik. Linköpings universitet, Tekniska högskolan.
    Norman, Patrick
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Beräkningsfysik. Linköpings universitet, Tekniska högskolan.
    Käll, Per-Olov
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Fysikalisk Kemi. Linköpings universitet, Tekniska högskolan.
    Uvdal, Kajsa
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    A simple polyol-free synthesis route to Gd2O3 nanoparticles for MRI applications: an experimental and theoretical study2012Inngår i: Journal of nanoparticle research, ISSN 1388-0764, E-ISSN 1572-896X, Vol. 14, nr 8Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Chelated gadolinium ions, e. g., GdDTPA, are today used clinically as contrast agents for magnetic resonance imaging (MRI). An attractive alternative contrast agent is composed of gadolinium oxide nanoparticles as they have shown to provide enhanced contrast and, in principle, more straightforward molecular capping possibilities. In this study, we report a new, simple, and polyol-free way of synthesizing 4-5-nm-sized Gd2O3 nanoparticles at room temperature, with high stability and water solubility. The nanoparticles induce high-proton relaxivity compared to Gd-DTPA showing r(1) and r(2) values almost as high as those for free Gd3+ ions in water. The Gd2O3 nanoparticles are capped with acetate and carbonate groups, as shown with infrared spectroscopy, near-edge X-ray absorption spectroscopy, X-ray photoelectron spectroscopy and combined thermogravimetric and mass spectroscopy analysis. Interpretation of infrared spectroscopy data is corroborated by extensive quantum chemical calculations. This nanomaterial is easily prepared and has promising properties to function as a core in a future contrast agent for MRI.

  • 106.
    Ahrén, Maria
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Söderlind, Fredrik
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Nanostrukturerade material. Linköpings universitet, Tekniska högskolan.
    Linares, Mathieu
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Beräkningsfysik. Linköpings universitet, Tekniska högskolan.
    Nordblad, Per
    Division of Solid State Physics, Department of Engineering Sciences, Uppsala University, Uppsala, Sweden.
    Norman, Patrick
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Beräkningsfysik. Linköpings universitet, Tekniska högskolan.
    Uvdal, Kajsa
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    One-step synthesis of sub 5 nm sized manganese oxide based nanoparticles2013Manuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Sub 5 nm sized manganese oxide nanoparticles; MnOx (1 ≤ x ≤ 2), were synthesized via a short time room temperature synthesis route. The nanoparticles are crystalline, spherically shaped and in the size range of 2-4 nm as shown by transmission electron microscopy studies. Selected area electron diffraction patterns were collected and their appearance indicated that the nanoparticle cores are composed of MnO. Also, co-existence of the (II) and (III) oxidation states at the nanoparticle surface was verified by results achieved from infrared spectroscopy and X-ray photoelectron spectroscopy. These measurements also supported presence of a minor amount of acetate groups as well as a negligible fraction of carbonate groups at the nanoparticle surfaces. The interpretation of the IR spectra was confirmed by quantum chemical calculations using the high spin manganese nanoparticle Mn12O12(OAc)16(H2O)4, as a model system for the MnOx nanoparticle surface. Bulk MnO and Mn2O3 are known to be antiferromagnetic. The magnetic properties are however somewhat dependent of the crystallite size and changes when scaling down to the nanoregion. The MnOx (1 ≤ x ≤ 2) nanoparticles investigated in this work show a superparamagnetic behavior with a blocking temperature of approximately 12 K proven by means of SQUID measurements. The relaxivities of the nanoparticles and the Mn(OAc)2 precursors were studied with a bench top NMR analyzer verifying nanoparticle r1 and r2 of 0.5 and 6 mMs-1 respectively. The r1 relaxivity is lower than what is earlier reported for Gd based contrast agent, but improvements are expected by further surface modification, due to increased rotational time and higher water dispersability.

  • 107.
    Ahsan, Aisha
    et al.
    Univ Basel, Switzerland.
    Mousavi, S. Fatemeh
    Univ Basel, Switzerland.
    Nijs, Thomas
    Univ Basel, Switzerland.
    Nowakowska, Sylwia
    Univ Basel, Switzerland.
    Popova, Olha
    Univ Basel, Switzerland.
    Wackerlin, Aneliia
    Univ Basel, Switzerland.
    Björk, Jonas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Gade, Lutz H.
    Heidelberg Univ, Germany.
    Jung, Thomas A.
    Paul Scherrer Inst, Switzerland.
    Phase Transitions in Confinements: Controlling Solid to Fluid Transitions of Xenon Atoms in an On-Surface Network2019Inngår i: Small, ISSN 1613-6810, E-ISSN 1613-6829, Vol. 15, nr 3, artikkel-id 1803169Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study reports on "phase" transitions of Xe condensates in on-surface confinements induced by temperature changes and local probe excitation. The pores of a metal-organic network occupied with 1 up to 9 Xe atoms are investigated in their propensity to undergo "condensed solid" to "confined fluid" transitions. Different transition temperatures are identified, which depend on the number of Xe atoms in the condensate and relate to the stability of the Xe clustering in the condensed "phase." This work reveals the feature-rich behavior of transitions of confined planar condensates, which provide a showcase toward future "phase-transition" storage media patterned by self-assembly. This work is also of fundamental interest as it paves the way to real space investigations of reversible solid to fluid transitions of magic cluster condensates in an array of extremely well-defined quantum confinements.

  • 108.
    Ahsan, Aisha
    et al.
    Univ Basel, Switzerland.
    Mousavi, S. Fatemeh
    Univ Basel, Switzerland.
    Nijs, Thomas
    Univ Basel, Switzerland.
    Nowakowska, Sylwia
    Univ Basel, Switzerland.
    Popova, Olha
    Univ Basel, Switzerland.
    Wackerlin, Aneliia
    Univ Basel, Switzerland.
    Björk, Jonas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Gade, Lutz H.
    Heidelberg Univ, Germany.
    Jung, Thomas A.
    Univ Basel, Switzerland; Paul Scherrer Inst, Switzerland.
    Watching nanostructure growth: kinetically controlled diffusion and condensation of Xe in a surface metal organic network2019Inngår i: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 11, nr 11, s. 4895-4903Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Diffusion, nucleation and growth provide the fundamental access to control nanostructure growth. In this study, the temperature activated diffusion of Xe at and between different compartments of an on-surface metal organic coordination network on Cu(111) has been visualized in real space. Xe atoms adsorbed at lower energy sites become mobile with increased temperature and gradually populate energetically more favourable binding sites or remain in a delocalized fluid form confined to diffusion along a topological subset of the on-surface network. These diffusion pathways can be studied individually under kinetic control via the chosen thermal energy kT of the sample and are determined by the network and sample architecture. The spatial distribution of Xe in its different modes of mobility and the time scales of the motion is revealed by Scanning Tunneling Microscopy (STM) at variable temperatures up to 40 K and subsequent cooling to 4 K. The system provides insight into the diffusion of a van der Waals gas on a complex structured surface and its nucleation and coarsening/growth into larger condensates at elevated temperature under thermodynamic conditions.

  • 109.
    Ahvenniemi, Esko
    et al.
    Aalto University, Finland.
    Akbashev, Andrew R.
    Stanford University, CA 94305 USA.
    Ali, Saima
    Aalto University, Finland.
    Bechelany, Mikhael
    University of Montpellier, France.
    Berdova, Maria
    University of Twente, Netherlands.
    Boyadjiev, Stefan
    Bulgarian Academic Science, Bulgaria.
    Cameron, David C.
    Masaryk University, Czech Republic.
    Chen, Rong
    Huazhong University of Science and Technology, Peoples R China.
    Chubarov, Mikhail
    University of Grenoble Alpes, France.
    Cremers, Veronique
    University of Ghent, Belgium.
    Devi, Anjana
    Ruhr University of Bochum, Germany.
    Drozd, Viktor
    St Petersburg State University, Russia.
    Elnikova, Liliya
    Institute Theoret and Expt Phys, Russia.
    Gottardi, Gloria
    Fdn Bruno Kessler, Italy.
    Grigoras, Kestutis
    VTT Technical Research Centre Finland, Finland.
    Hausmann, Dennis M.
    Lam Research Corp, OR 97062 USA.
    Seong Hwang, Cheol
    Seoul National University, South Korea; Seoul National University, South Korea.
    Jen, Shih-Hui
    Globalfoundries, NY 12203 USA.
    Kallio, Tanja
    Aalto University, Finland.
    Kanervo, Jaana
    Aalto University, Finland; Abo Akad University, Finland.
    Khmelnitskiy, Ivan
    St Petersburg Electrotech University of LETI, Russia.
    Han Kim, Do
    MIT, MA 02139 USA.
    Klibanov, Lev
    Techinsights, Canada.
    Koshtyal, Yury
    Ioffe Institute, Russia.
    Krause, A. Outi I.
    Aalto University, Finland.
    Kuhs, Jakob
    University of Ghent, Belgium.
    Kaerkkaenen, Irina
    Sentech Instruments GmbH, Germany.
    Kaariainen, Marja-Leena
    NovaldMedical Ltd Oy, Finland.
    Kaariainen, Tommi
    NovaldMedical Ltd Oy, Finland; University of Helsinki, Finland.
    Lamagna, Luca
    STMicroelectronics, Italy.
    Lapicki, Adam A.
    Seagate Technology Ireland, North Ireland.
    Leskela, Markku
    University of Helsinki, Finland.
    Lipsanen, Harri
    Aalto University, Finland.
    Lyytinen, Jussi
    Aalto University, Finland.
    Malkov, Anatoly
    Technical University, Russia.
    Malygin, Anatoly
    Technical University, Russia.
    Mennad, Abdelkader
    CDER, Algeria.
    Militzer, Christian
    Technical University of Chemnitz, Germany.
    Molarius, Jyrki
    Summa Semicond Oy, Finland.
    Norek, Malgorzata
    Mil University of Technology, Poland.
    Ozgit-Akgun, Cagla
    ASELSAN Inc, Turkey.
    Panov, Mikhail
    St Petersburg Electrotech University of LETI, Russia.
    Pedersen, Henrik
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska fakulteten.
    Piallat, Fabien
    KOBUS, France.
    Popov, Georgi
    University of Helsinki, Finland.
    Puurunen, Riikka L.
    VTT Technical Research Centre Finland, Finland.
    Rampelberg, Geert
    University of Ghent, Belgium.
    Ras, Robin H. A.
    Aalto University, Espoo, Finland.
    Rauwel, Erwan
    Tallinn University of Technology, Estonia.
    Roozeboom, Fred
    Eindhoven University of Technology, Netherlands; TNO, Netherlands.
    Sajavaara, Timo
    University of Jyvaskyla, Finland.
    Salami, Hossein
    University of Maryland, MD 20742 USA.
    Savin, Hele
    Aalto University, Finland.
    Schneider, Nathanaelle
    IRDEP CNRS, France; IPVF, France.
    Seidel, Thomas E.
    Seitek50, FL 32135 USA.
    Sundqvist, Jonas
    Fraunhofer Institute Ceram Technology and Syst IKTS, Germany.
    Suyatin, Dmitry B.
    Lund University, Sweden; Lund University, Sweden.
    Torndahl, Tobias
    Uppsala University, Sweden.
    van Ommen, J. Ruud
    Delft University of Technology, Netherlands.
    Wiemer, Claudia
    CNR, Italy.
    Ylivaara, Oili M. E.
    VTT Technical Research Centre Finland, Finland.
    Yurkevich, Oksana
    Immanuel Kant Balt Federal University, Russia.
    Recommended reading list of early publications on atomic layer deposition-Outcome of the "Virtual Project on the History of ALD"2017Inngår i: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 35, nr 1, artikkel-id 010801Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Atomic layer deposition (ALD), a gas-phase thin film deposition technique based on repeated, self-terminating gas-solid reactions, has become the method of choice in semiconductor manufacturing and many other technological areas for depositing thin conformal inorganic material layers for various applications. ALD has been discovered and developed independently, at least twice, under different names: atomic layer epitaxy (ALE) and molecular layering. ALE, dating back to 1974 in Finland, has been commonly known as the origin of ALD, while work done since the 1960s in the Soviet Union under the name "molecular layering" (and sometimes other names) has remained much less known. The virtual project on the history of ALD (VPHA) is a volunteer-based effort with open participation, set up to make the early days of ALD more transparent. In VPHA, started in July 2013, the target is to list, read and comment on all early ALD academic and patent literature up to 1986. VPHA has resulted in two essays and several presentations at international conferences. This paper, based on a poster presentation at the 16th International Conference on Atomic Layer Deposition in Dublin, Ireland, 2016, presents a recommended reading list of early ALD publications, created collectively by the VPHA participants through voting. The list contains 22 publications from Finland, Japan, Soviet Union, United Kingdom, and United States. Up to now, a balanced overview regarding the early history of ALD has been missing; the current list is an attempt to remedy this deficiency. (C) 2016 Author(s).

  • 110. Aichholzer, Oswin
    et al.
    Biro, Michael
    Demaine, Erik
    Demaine, Martin
    Eppstein, David
    Fekete, Sándor P.
    Hesterberg, Adam
    Kostitsyna, Irina
    Schmidt, Christiane
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Folding Polyominoes into (Poly)CubesInngår i: International journal of computational geometry and applications, ISSN 0218-1959Artikkel i tidsskrift (Fagfellevurdert)
  • 111.
    Aichigui, Victor
    et al.
    Linköpings universitet.
    Johansson, Elisabeth
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Logistik- och kvalitetsutveckling. Linköpings universitet, Tekniska fakulteten.
    Löfberg, Nina
    Karlstad University, SWEDEN.
    Witell, Lars
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Företagsekonomi. Linköpings universitet, Filosofiska fakulteten. Karlstad University, SWEDEN.
    Servitization in SME manufacturing firms: A one-way road2015Inngår i: 13th International Research Symposium on Service Excellence in Management, Shanghai, June 19-21, 2015, 2015, s. 965-968Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The importance for manufacturing firms to add services to their offerings has been asserted over and over again (Neu and Brown 2005). Adding services to product sales require manufacturing firms to develop other types of offerings such as maintenance services, hybrid offerings or integrated solutions. This implies using new and often unknown practices to be able to provide services. Previous research has focused on the benefits of servitization (Gebauer, Gustafsson, and Witell 2011), albeit in larger firms. Hence, similar research on Small and Medium sized Enterprises (SME) has been scarce. Furthermore, servitization as a unidirectional transition process can be questioned as researchers argue that manufacturing firms might offer different types of services simultaneously and might not have the intention to take the next step that a transition process suggests (Kowalkowski et al. 2015). Moreover, previous research shows that the step from offering after-sales services and repair to offering more advanced services, e.g. process-related services, is rather big. For those services different mindsets are required within the organization; more advanced services would require a service oriented mindset, whereas after-sales services only requires the firm to have a product oriented mindset (Löfberg 2014).

  • 112.
    Aid, Graham
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell miljöteknik. Linköpings universitet, Tekniska fakulteten.
    Operationalizing Industrial Ecology in the Waste Sector: Roles and tactics for circular value innovation2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The take-make-waste approach to resource management in human production and consumption systems is contributing to a variety of environmental and social problems worldwide. Additionally, as the world’s population and affluence increase, so do the negative impacts of poor resource management. Lifting the waste management (WM) sector into a new phase of development, which takes its lead from the ideals of Industrial Ecology and circular economy, is seen by many scholars and practitioners as one potential to assist in alleviating these impacts. While there are many studies on how more efficient inter-organizational resource management is (or could be) constructed, there are relatively few business development studies which have explored novel approaches (from roles to tactics) that WM organizations might operationalize toward more efficient resource management.

    The aim of this thesis is to contribute to the development of knowledge and understanding of how the waste management sector can operationalize more effective and efficient resource management. In approaching this aim, two research questions guided the exploration of: 1) novel roles for WM and 2) support tactics for such roles. Grounded in the broader context of Industrial Ecology (IE) and Business Development, five studies were performed. Two studies, focused on the novel roles of inter-organizational resource management and high value secondary resource extraction, were performed through literature review and interviews, and market driver analysis respectively. In exploring support tactics, two design and proof of concept studies were carried out to investigate data analysis tools for inter-organizational resource management, and one long-term action research engagement project was coordinated to study hands-on inter-organizational collaboration tactics.

    The studies highlighted that the Swedish WM sector holds some key capacities for operationalizing (and in some cases, is already developing) the novel resource management roles identified: industrial symbiosis facilitator, eco-industrial park manager, holistic facility management, and high value resource extractor. However, depending on the portfolio of services to be performed in such roles, several capacities may need to be developed or strengthened. Main opportunities seen for these roles were – staying ahead of market developments, and aligning activities with organizational goals. The main general risk related to these roles was insufficient returns on investment. Looking forward, the main enablers identified were policy leadership for more balanced market mechanisms, increasing use of external knowledge, developing long term partnerships, lobbying, stockpiling resources, and carefully crafting new business models.

    The tools developed for strategically applying external information toward the identification of opportunities within new roles showed tactical potential. However, their implementation in broader development processes has yet to be fully validated. The hands-on exploration of change oriented collaboration, highlighted collective system framing and goal setting and face-to-face interaction as key activities for inter-organizational approaches within roles such as industrial symbiosis facilitator.

    Throughout the studies, several novel roles were investigated. Each of these roles will need to be individually evaluated by directing bodies of WM organizations, and evaluated from the organization’s vision and strategy. If certain roles are chosen to be explored in more detail, they will need to be developed within full business models - addressing issues such as income structure, internal processes and capacities to be developed, and key customers. Through applying IE and business development concepts and findings, WM organizations have possibilities to translate ambitious visions into novel offerings.

    Delarbeid
    1. Expanding roles for the Swedish waste management sector in interorganizational resource management
    Åpne denne publikasjonen i ny fane eller vindu >>Expanding roles for the Swedish waste management sector in interorganizational resource management
    2017 (engelsk)Inngår i: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 124, s. 85-97Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Several waste management (WM) professionals see an ongoing shift in the focus of the industry, from that of atransport and treatment sector to that of a more integrated sustainable service provision and material productionsector. To further develop such transitional ambitions, WM organizations are increasingly looking toward interorganizationalresource network concepts (such as the circular economy and industrial symbiosis) as models ofhow they would like to create new value together with their customers and partners.This article aims to take a step in addressing uncertainties behind such transitions by analyzing barriers forinter-organizational resource management and in turn uncovering some potential opportunities and risks ofnovel offerings from the WM sector. Obstacles for developing innovative inter-organizational resource networkshave been identified based on studies of implementing industrial symbiosis networks. Subsequently, managingexecutives from Swedish private and public WM organizations were interviewed regarding the sector’s capacityto overcome such barriers – opportunities and risks of providing new resource management services – and howtheir organizations might approach the role of actively facilitating more resource efficient regions.Eco-Industrial park management and contracting out holistic resource management are some areas in whichthe respondents see WM organizations offering new services. In relation to such approaches, various risks (e.g.being cut out of investment benefits, or unstable supply) and opportunities (e.g. new markets and enhancedsustainability profiles) were identified. Additionally, it was seen that WM companies would need to makesubstantial changes to their business approach, becoming less dependent on flows of mixed materials forexample, if they are to become even more central value chain actors. To strengthen such approaches, it was seenthat the sector will need to find methods to strategically build strong, long term partnerships, expand upon andtake advantage of available knowledge resources (i.e. best practice technologies and regional material flows),and explore new business models (i.e. stockpiling, park management, or waste minimization). Additionally,working with sector representatives to argue for a more balanced market conditions next to primary productionshould assist the viability of new offerings in the wider market.

    Emneord
    Circular economy, Industrial symbiosis, Recycling, Business development, Green innovation
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-137456 (URN)10.1016/j.resconrec.2017.04.007 (DOI)000403860200009 ()
    Merknad

    Funding agencies: Ragnar Sellbergs Foundation

    Tilgjengelig fra: 2017-05-16 Laget: 2017-05-16 Sist oppdatert: 2017-08-07
    2. Driving Forces and Inhibitors of Secondary Stock Extraction
    Åpne denne publikasjonen i ny fane eller vindu >>Driving Forces and Inhibitors of Secondary Stock Extraction
    2016 (engelsk)Inngår i: The Open Waste Management Journal, ISSN 1876-4002, E-ISSN 1876-4002, Vol. 9, s. 11-18Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Even though it’s well known that our common resources are limited and that recycling is key for a sustainable future; inreality we see few examples of true recycling where virgin raw material is substituted by waste. There are endless numbers ofexamples where waste is utilized to some extent without solving the core issue: reducing the need of extracting virgin raw materials.This article analyses some of the driving forces and inhibitors of secondary stock extraction to explore why it’s so difficult establishlarge scale secondary stock extraction although suitable technologies are available. The authors discuss and suggest possible ways forreducing some of the main barriers presented.

    Emneord
    Circular economy, Economy, Recycling, Resources, Sustainability
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-137459 (URN)10.2174/1876400201609010011 (DOI)
    Tilgjengelig fra: 2017-05-16 Laget: 2017-05-16 Sist oppdatert: 2017-11-29
    3. Looplocal - a heuristic visualization tool to support the strategic facilitation of industrial symbiosis
    Åpne denne publikasjonen i ny fane eller vindu >>Looplocal - a heuristic visualization tool to support the strategic facilitation of industrial symbiosis
    2015 (engelsk)Inngår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 98, s. 328-335Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Industrial symbiosis (IS) developments have been differentiated as self-organized, facilitated, and planned. This article introduces a tool, Looplocal, which has been built with objectives to support the strategic facilitation of IS. Looplocal is a visualization tool built to assist in 1) Simplifying the identification of regions susceptible to new industrial symbiosis facilitation activities 2) Enabling proactive and targeted marketing of potential exchanges to key actors in specific regions and 3) Assisting facilitators to assess the various strategies and consequential engagement and analysis methodologies suitable for additional IS development in specific regions. The tool compares industrial symbiosis data and estimated regional material and energy flows (on a facility level) to identify potential IS transfer information along with key stakeholder and network data. The authors have performed a proof of concept run of this tool on Sweden. In its early stages of application the method has given results seen as useful for identifying regions susceptible to the investment of symbiosis facilitators' time and resources. The material focus and customization possibilities for the tool show potential for a spectrum of potential facilitators: from waste management companies to national or regional authorities. In conjunction with long term business models, such a tool might be utilized throughout an adaptive chain of facilitation activities and aims.

    sted, utgiver, år, opplag, sider
    Elsevier, 2015
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-137462 (URN)10.1016/j.jclepro.2014.08.012 (DOI)000356194300033 ()2-s2.0-84929966422 (Scopus ID)
    Merknad

    QC 20150713

    Tilgjengelig fra: 2015-07-13 Laget: 2017-05-16 Sist oppdatert: 2017-05-16bibliografisk kontrollert
    4. Secondary Resources in the Bio-Based Economy: A Computer Assisted Survey of Value Pathways in Academic Literature
    Åpne denne publikasjonen i ny fane eller vindu >>Secondary Resources in the Bio-Based Economy: A Computer Assisted Survey of Value Pathways in Academic Literature
    2017 (engelsk)Inngår i: Waste and Biomass Valorization, ISSN 1877-2641, E-ISSN 1877-265X, Vol. 8, nr 7, s. 2229-2246Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Research on value pathways for organic wastes has been steadily increasing in recent decades. There have been few considerably broad overview studies of such materials and their valuation potential in the bio-based economy in part because of the vast multitude of materials and processes that can be used to produce energy carriers, chemicals, and materials of value. This article explores how automated data analysis approaches can help in analyzing large bodies of text to distill and present potential value pathways for secondary (waste) bio-based materials. The study employed multiple methods (literature collection, topic modelling, and co-occurrence analysis) on a collection of abstracts from 53,292 academic articles covering technologies, applications, and products (TAPs) for bio-based wastes. The results of both the topic modelling and co-occurrence analysis are presented as online interactive web pages. The topic modelling presented an overview of research clusters related to secondary organic resources, processes, and disciplines. The co-occurrence analysis helped to understand which TAPs are researched in relation to a broad spectrum of organic wastes. Co-occurrences were evaluated using the Normalized Pointwise Mutual Information measure to locate terms which co-occur more frequently than would be expected by chance. Through the use of detailed lists of organic wastes and TAPs, the co-occurrence method mapped out 7118 unique intersections between 473 specific wastes and 228 TAPs. This technique enables us to find seemingly non-obvious valorization pathways such as the re-use of oyster shells as catalysts for bio-diesel production and bioplastic production from brewery waste. While a proof-of-concept, this work points the way for using Big Data to suggest novel pathways for implementing the Circular Economy.

    sted, utgiver, år, opplag, sider
    Springer, 2017
    Emneord
    By-product, Waste valorization, Circular economy, Recycling, Industrial symbiosis, Big Data
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-138067 (URN)10.1007/s12649-017-9975-0 (DOI)000411975600001 ()2-s2.0-85020108904 (Scopus ID)
    Merknad

    Funding agencies: Ragnar Sellbergs Foundation

    Tilgjengelig fra: 2017-06-08 Laget: 2017-06-08 Sist oppdatert: 2017-10-23bibliografisk kontrollert
    5. Improvement of aggregate cycles in Stockholm and the Baltic Region: Activities and results of the BRA initiative
    Åpne denne publikasjonen i ny fane eller vindu >>Improvement of aggregate cycles in Stockholm and the Baltic Region: Activities and results of the BRA initiative
    2012 (engelsk)Inngår i: Proceedings of the 8th International conference on Sustainable management of waste and recycled materials in construction, Gothenburg, Sweden, 30 May - 1 June 2012 / [ed] M. Arm, C. Vandecasteele, J. Heynen, P. Suer and B. Lind, Swedish Geotechnical Institute , 2012, s. 1-9Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    From 2009 until 2011 project BRA (Bygg-och Rivningsavfall i Stockholms Län) “Construction and Demolition (C&D) waste in Stockholm County” was coordinated from the division of Industrial Ecology, KTH. This project was focused on actively improving (from plural perspectives) the cycles of C&D (specifically non-metallic inert) materials in the region. In response to the normative aim and inter-systems complexity, a highly participative action research procedure was adopted. Through processes of network communication, workshops, a course, and an international symposium - a number of issues (such as market development, recycled product quality, greenhouse gas impacts, collaborative planning, and statistics) were prioritized, researched, and acted upon. Indicators for measuring progress in selected areas were developed and preliminary action plans created. At a final co-organized symposium Swedish delegates laid the groundwork for the establishment of a Swedish C&D recycling b ranch organization. This initiative of continued collaboration between and within sectors is seen as a vehicle for the priorities and action requirements identified in BRA to be further enabled and held in focus. Furthermore, these actors taking ownership of the process is seen as a success in accordance to the original aims and the need for further cycles of evaluation, planning, and action.

    sted, utgiver, år, opplag, sider
    Swedish Geotechnical Institute, 2012
    Emneord
    by-product, recycling, synergy, industrial ecology, facilitation
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-137463 (URN)
    Konferanse
    WASCON 2012 – towards effective, durable and sustainable production and use of alternative materials in construction. 8th International conference on sustainable management of waste and recycled materials in construction, Gothenburg, Sweden, 30 May - 1 June 2012
    Merknad

    QC 20130522

    Tilgjengelig fra: 2013-05-20 Laget: 2017-05-16 Sist oppdatert: 2017-05-16bibliografisk kontrollert
  • 113.
    Aid, Graham
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell miljöteknik. Linköpings universitet, Tekniska fakulteten. Ragn-Sells AB.
    Eklund, Mats
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell miljöteknik. Linköpings universitet, Tekniska fakulteten.
    Anderberg, Stefan
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell miljöteknik. Linköpings universitet, Tekniska fakulteten.
    Baas, Leo
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell miljöteknik. Linköpings universitet, Tekniska fakulteten.
    Expanding roles for the Swedish waste management sector in interorganizational resource management2017Inngår i: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 124, s. 85-97Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Several waste management (WM) professionals see an ongoing shift in the focus of the industry, from that of atransport and treatment sector to that of a more integrated sustainable service provision and material productionsector. To further develop such transitional ambitions, WM organizations are increasingly looking toward interorganizationalresource network concepts (such as the circular economy and industrial symbiosis) as models ofhow they would like to create new value together with their customers and partners.This article aims to take a step in addressing uncertainties behind such transitions by analyzing barriers forinter-organizational resource management and in turn uncovering some potential opportunities and risks ofnovel offerings from the WM sector. Obstacles for developing innovative inter-organizational resource networkshave been identified based on studies of implementing industrial symbiosis networks. Subsequently, managingexecutives from Swedish private and public WM organizations were interviewed regarding the sector’s capacityto overcome such barriers – opportunities and risks of providing new resource management services – and howtheir organizations might approach the role of actively facilitating more resource efficient regions.Eco-Industrial park management and contracting out holistic resource management are some areas in whichthe respondents see WM organizations offering new services. In relation to such approaches, various risks (e.g.being cut out of investment benefits, or unstable supply) and opportunities (e.g. new markets and enhancedsustainability profiles) were identified. Additionally, it was seen that WM companies would need to makesubstantial changes to their business approach, becoming less dependent on flows of mixed materials forexample, if they are to become even more central value chain actors. To strengthen such approaches, it was seenthat the sector will need to find methods to strategically build strong, long term partnerships, expand upon andtake advantage of available knowledge resources (i.e. best practice technologies and regional material flows),and explore new business models (i.e. stockpiling, park management, or waste minimization). Additionally,working with sector representatives to argue for a more balanced market conditions next to primary productionshould assist the viability of new offerings in the wider market.

  • 114.
    Aiempanakit, Montri
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Helmersson, Ulf
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Aijaz, Asim
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Larsson, Petter
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan.
    Magnusson, Roger
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad optik. Linköpings universitet, Tekniska fakulteten.
    Jensen, Jens
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska högskolan.
    Kubart, Tomas
    Uppsala University.
    Effect of peak power in reactive high power impulse magnetron sputtering of titanium dioxide2011Inngår i: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 205, nr 20, s. 4828-4831Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effect of peak power in a high power impulse magnetron sputtering (HiPIMS) reactive deposition of TiO(2) films has been studied with respect to the deposition rate and coating properties. With increasing peak power not only the ionization of the sputtered material increases but also their energy. In order to correlate the variation in the ion energy distributions with the film properties, the phase composition, density and optical properties of the films grown with different HiPIMS-parameters have been investigated and compared to a film grown using direct current magnetron sputtering (DCMS). All experiments were performed for constant average power and pulse on time (100W and 35 mu s, respectively), different peak powers were achieved by varying the frequency of pulsing. Ion energy distributions for Ti and O and its dependence on the process conditions have been studied. It was found that films with the highest density and highest refractive index were grown under moderate HiPIMS conditions (moderate peak powers) resulting in only a small loss in mass-deposition rate compared to DCMS. It was further found that TiO2 films with anatase and rutile phases can be grown at room temperature without substrate heating and without post-deposition annealing.

  • 115.
    Aigner, Mats
    et al.
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska högskolan.
    Tjatyrko, Vitalij
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska fakulteten.
    Nyagahakwa, Venuste
    National University of Rwanda, Rwanda .
    ON COUNTABLE FAMILIES OF SETS WITHOUT THE BAIRE PROPERTY2013Inngår i: Colloquium Mathematicum, ISSN 0010-1354, E-ISSN 1730-6302, Vol. 133, nr 2, s. 179-187Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We suggest a method of constructing decompositions of a topological space X having an open subset homeomorphic to the space (R-n , tau), where n is an integer greater than= 1 and tau is any admissible extension of the Euclidean topology of R-n (in particular, X can be a finite-dimensional separable metrizable manifold), into a countable family F of sets (dense in X and zero-dimensional in the case of manifolds) such that the union of each non-empty proper subfamily of F does not have the Baire property in X.

  • 116.
    Aigner, Mats
    et al.
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska fakulteten.
    Tjatyrko, Vitalij
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska fakulteten.
    Nyagahakwa, Venuste
    National University of Rwanda, Rwanda.
    THE ALGEBRA OF SEMIGROUPS OF SETS2015Inngår i: Mathematica Scandinavica, ISSN 0025-5521, E-ISSN 1903-1807, Vol. 116, nr 2, s. 161-170Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We study the algebra of semigroups of sets (i.e. families of sets closed under finite unions) and its applications. For each n greater than 1 we produce two finite nested families of pairwise different semigroups of sets consisting of subsets of R" without the Baire property.

  • 117.
    Aihara, ShinIchi
    et al.
    Tokyo University of Science Suwa, Japan.
    Bagchi, Arunabha
    University of Twente, Netherlands.
    Saha, Saikat
    Linköpings universitet, Institutionen för systemteknik. Linköpings universitet, Tekniska fakulteten.
    Filtering for Stochastic Volatility by Using Exact Sampling and Application to Term Structure Modeling2015Inngår i: INFORMATICS IN CONTROL, AUTOMATION AND ROBOTICS, Springer Science Business Media , 2015, Vol. 325, s. 329-348Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The Bates stochastic volatility model is widely used in the finance problem and the sequential parameter estimation problem becomes important. By using the exact simulation technique, a particle filter for estimating stochastic volatility is constructed. The system parameters are sequentially estimated with the aid of parallel filtering algorithm with the new resampling procedure. The proposed filtering procedure is also applied to the modeling of the term structure dynamics. Simulation studies for checking the feasibility of the developed scheme are demonstrated.

  • 118.
    Aijaz, Asim
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska högskolan. Uppsala University, Sweden.
    Louring, Sascha
    Aarhus University, Denmark; Danish Technology Institute, Denmark.
    Lundin, Daniel
    University of Paris Saclay, France.
    Kubart, Tomas
    Uppsala University, Sweden.
    Jensen, Jens
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Sarakinos, Kostas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Nanodesign. Linköpings universitet, Tekniska fakulteten.
    Helmersson, Ulf
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska fakulteten.
    Synthesis of hydrogenated diamondlike carbon thin films using neon-acetylene based high power impulse magnetron sputtering discharges2016Inngår i: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 34, nr 6, artikkel-id 061504Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hydrogenated diamondlike carbon (DLC:H) thin films exhibit many interesting properties that can be tailored by controlling the composition and energy of the vapor fluxes used for their synthesis. This control can be facilitated by high electron density and/or high electron temperature plasmas that allow one to effectively tune the gas and surface chemistry during film growth, as well as the degree of ionization of the film forming species. The authors have recently demonstrated by adding Ne in an Ar-C high power impulse magnetron sputtering (HiPIMS) discharge that electron temperatures can be effectively increased to substantially ionize C species [Aijaz et al., Diamond Relat. Mater. 23, 1 (2012)]. The authors also developed an Ar-C2H2 HiPIMS process in which the high electron densities provided by the HiPIMS operation mode enhance gas phase dissociation reactions enabling control of the plasma and growth chemistry [Aijaz et al., Diamond Relat. Mater. 44, 117 (2014)]. Seeking to further enhance electron temperature and thereby promote electron impact induced interactions, control plasma chemical reaction pathways, and tune the resulting film properties, in this work, the authors synthesize DLC: H thin films by admixing Ne in a HiPIMS based Ar/C2H2 discharge. The authors investigate the plasma properties and discharge characteristics by measuring electron energy distributions as well as by studying discharge current characteristics showing an electron temperature enhancement in C2H2 based discharges and the role of ionic contribution to the film growth. These discharge conditions allow for the growth of thick (amp;gt;1 mu m) DLC: H thin films exhibiting low compressive stresses (similar to 0.5 GPa), high hardness (similar to 25 GPa), low H content (similar to 11%), and density in the order of 2.2 g/cm(3). The authors also show that film densification and change of mechanical properties are related to H removal by ion bombardment rather than subplantation. (C) 2016 American Vacuum Society.

  • 119.
    Aikawa, Hiroaki
    et al.
    Hokkaido Univ, Japan.
    Björn, Anders
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska fakulteten.
    Björn, Jana
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska fakulteten.
    Shanmugalingam, Nageswari
    Univ Cincinnati, OH 45221 USA.
    Dichotomy of global capacity density in metric measure spaces2018Inngår i: Advances in Calculus of Variations, ISSN 1864-8258, E-ISSN 1864-8266, Vol. 11, nr 4, s. 387-404Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The variational capacity cap(p) in Euclidean spaces is known to enjoy the density dichotomy at large scales, namely that for every E subset of R-n, infx is an element of R(n)cap(p)(E boolean AND B(x, r), B(x, 2r))/cap(p)(B(x, r), B(x, 2r)) is either zero or tends to 1 as r -amp;gt; infinity. We prove that this property still holds in unbounded complete geodesic metric spaces equipped with a doubling measure supporting a p-Poincare inequality, but that it can fail in nongeodesic metric spaces and also for the Sobolev capacity in R-n. It turns out that the shape of balls impacts the validity of the density dichotomy. Even in more general metric spaces, we construct families of sets, such as John domains, for which the density dichotomy holds. Our arguments include an exact formula for the variational capacity of superlevel sets for capacitary potentials and a quantitative approximation from inside of the variational capacity.

  • 120.
    Ail, Ujwala
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Jafari, Mohammad Javad
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Wang, Hui
    Linköpings universitet, Institutionen för teknik och naturvetenskap. Linköpings universitet, Tekniska fakulteten.
    Ederth, Thomas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Berggren, Magnus
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Crispin, Xavier
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Thermoelectric Properties of Polymeric Mixed Conductors2016Inngår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 26, nr 34, s. 6288-6296Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The thermoelectric (TE) phenomena are intensively explored by the scientific community due to the rather inefficient way energy resources are used with a large fraction of energy wasted in the form of heat. Among various materials, mixed ion-electron conductors (MIEC) are recently being explored as potential thermoelectrics, primarily due to their low thermal conductivity. The combination of electronic and ionic charge carriers in those inorganic or organic materials leads to complex evolution of the thermovoltage (Voc) with time, temperature, and/or humidity. One of the most promising organic thermoelectric materials, poly(3,4-ethyelenedioxythiophene)-polystyrene sulfonate (PEDOT-PSS), is an MIEC. A previous study reveals that at high humidity, PEDOT-PSS undergoes an ionic Seebeck effect due to mobile protons. Yet, this phenomenon is not well understood. In this work, the time dependence of the Voc is studied and its behavior from the contribution of both charge carriers (holes and protons) is explained. The presence of a complex reorganization of the charge carriers promoting an internal electrochemical reaction within the polymer film is identified. Interestingly, it is demonstrated that the time dependence behavior of Voc is a way to distinguish between three classes of polymeric materials: electronic conductor, ionic conductor, and mixed ionic–electronic conductor

  • 121.
    Ail, Ujwala
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Ullah Khan, Zia
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Granberg, Hjalmar
    Innventia AB, Sweden.
    Berthold, Fredrik
    Innventia AB, Sweden.
    Parasuraman, Rajasekar
    Mat Research Centre, India.
    Urnarji, Arun M.
    Mat Research Centre, India.
    Slettengren, Kerstin
    Innventia AB, Sweden.
    Pettersson, Henrik
    Innventia AB, Sweden.
    Crispin, Xavier
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Room temperature synthesis of transition metal silicide-conducting polymer micro-composites for thermoelectric applications2017Inngår i: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 225, s. 55-63Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Organic polymer thermoelectrics (TE) as well as transition metal (TM) silicides are two thermoelectric class of materials of interest because they are composed of atomic elements of high abundatice; which is a prerequisite for mass implementation of thermoelectric (TE) solutions for solar and waste heat recovery. But both materials have drawbacks when it comes to finding low-cost manufacturing. The metal silicide needs high temperature (amp;gt;1000 degrees C) for creating TE legs in a device from solid powder, but it is easy to achieve long TE legs in this case. On the contrary, organic TEs are synthesized at low temperature from solution. However, it is difficult to form long legs or thick films because of their low solubility. In this work, we propose a novel method for the room temperature synthesis of TE composite containing the microparticles of chromium disilicide; CrSi2 (inorganic filler) in an organic matrix of nanofibrillated cellulose-poly(3,4-ethyelenedioxythiophene)-polystyrene sulfonate (NFC-PEDOT:PSS). With this method, it is easy to create long TE legs in a room temperature process. The originality of the approach is the use of conducting polymer aerogel microparticles mixed with CrSi2 microparticles to obtain a composite solid at room temperature under pressure. We foresee that the method can be scaled up to fabricate and pattern TE modules. The composite has an electrical conductivity (sigma) of 5.4 +/- 0.5 S/cm and the Seebeck coefficient (a) of 88 +/- 9 mu V/K, power factor (alpha(2)sigma) of 4 +/- 1 mu Wm(-1) K-2 at room temperature. At a temperature difference of 32 degrees C, the output power/unit area drawn across the load, with the resistance same as the internal resistance of the device is 0.6 +/- 0.1 mu W/cm(2). (C) 2017 Elsevier B.V. All rights reserved.

  • 122.
    Aili, Daniel
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Selegård, Robert
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Baltzer, Lars
    Division of Organic Chemistry, Department of Biochemistry and Organic Chemistry, BMC, Box 576, Uppsala University, SE-751 23 Uppsala, Sweden.
    Enander, Karin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Liedberg, Bo
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Colorimetric Protein Sensing by Controlled Assembly of Gold Nanoparticles Functionalized with Synthetic Receptors2009Inngår i: Small, ISSN 1613-6810, Vol. 5, nr 21, s. 2445-2452Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A strategy for colorimetric sensing of proteins, based on the induced assembly of polypeptide-functionalized gold nanoparticles, is described. Recognition was accomplished using a polypeptide sensor scaffold designed to specifically bind the model analyte, human carbonic anhydrase II (HCAII). The extent of particle aggregation, induced by the Zn2+-triggered dimerization and folding of a second polypeptide also present on the surface of the gold nanoparticle, gave a readily detectable colorimetric shift that was dependent on the concentration of the target protein. In the absence of HCAII, particle aggregation resulted in a major redshift of the plasmon peak whereas analyte binding prevented formation of dense aggregates, significantly reducing the magnitude of the redshift. The limit of detection of HCAII was estimated to be around 15 nM. The versatility of the technique was demonstrated using a second model system based on the recognition of a peptide sequence from the tobacco mosaic virus coat protein (TMVP by a recombinant antibody fragment. This strategy is proposed as a generic platform for robust and specific protein analysis that can be further developed for monitoring a wide range of target proteins.

  • 123.
    Aili, Daniel
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Selegård, Robert
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Baltzer, Lars
    Uppsala University .
    Enander, Karin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Liedberg, Bo
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Colorimetric sensing: Small 21/20092009Inngår i: Small, ISSN 1613-6810, E-ISSN 1613-6829, Vol. 5, nr 21Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    The cover picture illustrates a novel concept for colorimetric protein sensing based on the controllable assembly of polypeptide-functionalized gold nanoparticles. Recognition of the analyte is accomplished by polypeptide-based synthetic receptors immobilized on gold nanoparticles. Also present on the particle surface is a de novo-designed helix-loop-helix polypeptide that homodimerizes and folds into four-helix bundles in the presence of Zn2+, resulting in particle aggregation. Analyte binding interferes with the folding-induced aggregation, giving rise to a clearly detectable colorimetric response.

  • 124.
    Ajjan, Fátima
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ambrogi, Martina
    Max Planck Institute Colloids and Interfaces, Germany.
    Ayalneh Tiruye, Girum
    IMDEA Energy Institute, Spain.
    Cordella, Daniela
    University of Liege ULg, Belgium.
    Fernandes, Ana M.
    POLYMAT University of Basque Country UPV EHU, Spain.
    Grygiel, Konrad
    Max Planck Institute Colloids and Interfaces, Germany.
    Isik, Mehmet
    POLYMAT University of Basque Country UPV EHU, Spain.
    Patil, Nagaraj
    University of Liege ULg, Belgium.
    Porcarelli, Luca
    POLYMAT University of Basque Country UPV EHU, Spain.
    Rocasalbas, Gillem
    KIOMedPharma, Belgium.
    Vendramientto, Giordano
    University of Bordeaux, France.
    Zeglio, Erica
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Antonietti, Markus
    Max Planck Institute Colloids and Interfaces, Germany.
    Detrembleur, Cristophe
    University of Liege ULg, Belgium.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Jerome, Christine
    University of Liege ULg, Belgium.
    Marcilla, Rebeca
    IMDEA Energy Institute, Spain.
    Mecerreyes, David
    POLYMAT University of Basque Country UPV EHU, Spain; Basque Fdn Science, Spain.
    Moreno, Monica
    POLYMAT University of Basque Country UPV EHU, Spain.
    Taton, Daniel
    University of Bordeaux, France.
    Solin, Niclas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Yuan, Jiayin
    Max Planck Institute Colloids and Interfaces, Germany.
    Innovative polyelectrolytes/poly(ionic liquid)s for energy and the environment2017Inngår i: Polymer international, ISSN 0959-8103, E-ISSN 1097-0126, Vol. 66, nr 8, s. 1119-1128Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    This paper presents the work carried out within the European project RENAISSANCE-ITN, which was dedicated to the development of innovative polyelectrolytes for energy and environmental applications. Within the project different types of innovative polyelectrolytes were synthesized such as poly(ionic liquid)s coming from renewable or natural ions, thiazolium cations, catechol functionalities or from a new generation of cheap deep eutectic monomers. Further, macromolecular architectures such as new poly(ionic liquid) block copolymers and new (semi)conducting polymer/polyelectrolyte complexes were also developed. As the final goal, the application of these innovative polymers in energy and the environment was investigated. Important advances in energy storage technologies included the development of new carbonaceous materials, new lignin/conducting polymer biopolymer electrodes, new iongels and single-ion conducting polymer electrolytes for supercapacitors and batteries and new poly(ionic liquid) binders for batteries. On the other hand, the use of innovative polyelectrolytes in sustainable environmental technologies led to the development of new liquid and dry water, new materials for water cleaning technologies such as flocculants, oil absorbers, new recyclable organocatalyst platforms and new multifunctional polymer coatings with antifouling and antimicrobial properties. All in all this paper demonstrates the potential of poly(ionic liquid)s for high-value applications in energy and enviromental areas. (c) 2017 Society of Chemical Industry

  • 125.
    Ajjan, Fátima
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Casado, N.
    University of Basque Country, Spain.
    Rebis, Tomasz
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Elfwing, Anders
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Solin, Niclas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Mecerreyes, D.
    University of Basque Country, Spain; Ikerbasque, Spain.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    High performance PEDOT/lignin biopolymer composites for electrochemical supercapacitors2016Inngår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 4, nr 5, s. 1838-1847Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Developing sustainable organic electrode materials for energy storage applications is an urgent task. We present a promising candidate based on the use of lignin, the second most abundant biopolymer in nature. This polymer is combined with a conducting polymer, where lignin as a polyanion can behave both as a dopant and surfactant. The synthesis of PEDOT/Lig biocomposites by both oxidative chemical and electrochemical polymerization of EDOT in the presence of lignin sulfonate is presented. The characterization of PEDOT/Lig was performed by UV-Vis-NIR spectroscopy, FTIR infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, cyclic voltammetry and galvanostatic charge-discharge. PEDOT doped with lignin doubles the specific capacitance (170.4 F g(-1)) compared to reference PEDOT electrodes (80.4 F g(-1)). The enhanced energy storage performance is a consequence of the additional pseudocapacitance generated by the quinone moieties in lignin, which give rise to faradaic reactions. Furthermore PEDOT/Lig is a highly stable biocomposite, retaining about 83% of its electroactivity after 1000 charge/discharge cycles. These results illustrate that the redox doping strategy is a facile and straightforward approach to improve the electroactive performance of PEDOT.

  • 126.
    Ajjan, Fátima
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Javad Jafari, Mohammad
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Rebis, T.
    Poznan University of Tech, Poland.
    Ederth, Thomas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Spectroelectrochemical investigation of redox states in a polypyrrole/lignin composite electrode material2015Inngår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 3, nr 24, s. 12927-12937Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We report spectroelectrochemical studies to investigate the charge storage mechanism of composite polypyrrole/lignin electrodes. Renewable bioorganic electrode materials were produced by electropolymerization of pyrrole in the presence of a water-soluble lignin derivative acting as a dopant. The resulting composite exhibited enhanced charge storage abilities due to a lignin-based faradaic process, which was expressed after repeated electrochemical redox of the material. The in situ FTIR spectroelectrochemistry results show the formation of quinone groups, and reversible oxidation-reduction of these groups during charge-discharge experiments in the electrode materials. The most significant IR bands include carbonyl absorption near 1705 cm(-1), which is attributed to the creation of quinone moieties during oxidation, and absorption at 1045 cm(-1) which is due to hydroquinone moieties.

  • 127.
    Ajjan Godoy, Fátima Nadia
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Biohybrid Polymer Electrodes for Renewable Energy Storage2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Daily and seasonally fluctuating energy supply and demand requires adequate energy storage solutions. In recent years electrochemical supercapacitors have attracted considerable attention due to their ability to both store and deliver electrical energy efficiently. Our efforts are focused on developing and optimizing sustainable organic electrode materials for supercapacitors based on renewable bioorganic materials, offering a cheap, environmentally friendly and scalable alternative to store energy. In particular, we are using the second most abundant biopolymer in nature, lignin (Lig), which is an insulating material. However, when used in combination with electroactive and conducting polymers such as polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT), the biohybrid electrodes PPy/Lig and PEDOT/Lig display significantly enhanced energy storage performance as compared to the pristine conducting polymers without the lignin. Redox cyclic voltammetry and galvanostatic charge/discharge measurements indicate that the enhanced performance is due to the additional pseudocapacitance generated by the quinone moieties in lignin. Moreover, a conjugated redoxpolymer poly(aminoanthraquinone) PAAQ, with intrinsic quinone functions and excellentstability, has been combined with lignin and PEDOT resulting in a trihybrid bioelectrode. PEDOT compensates the low conductivity of PAAQ and provides electrical pathways to the quinone groups. The electrochemically generated quinones undergo a two electron, two protonredox process within the biohybrid electrodes as revealed by FTIR spectroelectrochemistry.These remarkable features reveal the exciting potential of a full organic energy storage device with long cycle life. Therefore, supercapacitor devices were designed in symmetric or asymmetric two electrode configuration. The best electrochemical performance was achieved by the asymmetric supercapacitor based on PEDOT+Lignin/PAAQ as the positive electrode and PEDOT/PAAQ as the negative electrode. This device exhibits superior electrochemical performance and outstanding stability after 10000 charge/discharge cycles due to the synergistic effect of the two electrodes. Finally, we have characterized the response of this supercapacitor device when charged with the intermittent power supply from an organic photovoltaic module. We have designed charging/discharging conditions such that reserve power was available in the storage device at all times. This work has resulted in an inexpensive fully organic system witht he dual function of energy conversion and storage.

    Delarbeid
    1. Biopolymer hybrid electrodes for scalable electricity storage
    Åpne denne publikasjonen i ny fane eller vindu >>Biopolymer hybrid electrodes for scalable electricity storage
    2016 (engelsk)Inngår i: Materials Horizons, ISSN 2051-6347, E-ISSN 2051-6355, Vol. 3, nr 3, s. 174-185Artikkel, forskningsoversikt (Fagfellevurdert) Published
    Abstract [en]

    Powering the future, while maintaining a cleaner environment and a strong socioeconomic growth, is going to be one of the biggest challenges faced by mankind in the 21st century. The first step in overcoming the challenge for a sustainable future is to use energy more efficiently so that the demand for fossil fuels can be reduced drastically. The second step is a transition from the use of fossil fuels to renewable energy sources. In this sense, organic electrode materials are becoming increasingly attractive compared to inorganic electrode materials which have reached a plateau regarding performance and have severe drawbacks in terms of cost, safety and environmental friendliness. Using organic composites based on conducting polymers, such as polypyrrole, and abundant, cheap and naturally occurring biopolymers rich in quinones, such as lignin, has recently emerged as an interesting alternative. These materials, which exhibit electronic and ionic conductivity, provide challenging opportunities in the development of new charge storage materials. This review presents an overview of recent developments in organic biopolymer composite electrodes as renewable electroactive materials towards sustainable, cheap and scalable energy storage devices.

    sted, utgiver, år, opplag, sider
    ROYAL SOC CHEMISTRY, 2016
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-128741 (URN)10.1039/c5mh00261c (DOI)000375296600002 ()
    Merknad

    Funding Agencies|Knut and Alice Wallenberg Foundation; Wallenberg Scholar grant

    Tilgjengelig fra: 2016-05-31 Laget: 2016-05-30 Sist oppdatert: 2017-11-30
    2. Spectroelectrochemical investigation of redox states in a polypyrrole/lignin composite electrode material
    Åpne denne publikasjonen i ny fane eller vindu >>Spectroelectrochemical investigation of redox states in a polypyrrole/lignin composite electrode material
    Vise andre…
    2015 (engelsk)Inngår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 3, nr 24, s. 12927-12937Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    We report spectroelectrochemical studies to investigate the charge storage mechanism of composite polypyrrole/lignin electrodes. Renewable bioorganic electrode materials were produced by electropolymerization of pyrrole in the presence of a water-soluble lignin derivative acting as a dopant. The resulting composite exhibited enhanced charge storage abilities due to a lignin-based faradaic process, which was expressed after repeated electrochemical redox of the material. The in situ FTIR spectroelectrochemistry results show the formation of quinone groups, and reversible oxidation-reduction of these groups during charge-discharge experiments in the electrode materials. The most significant IR bands include carbonyl absorption near 1705 cm(-1), which is attributed to the creation of quinone moieties during oxidation, and absorption at 1045 cm(-1) which is due to hydroquinone moieties.

    sted, utgiver, år, opplag, sider
    ROYAL SOC CHEMISTRY, 2015
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-120069 (URN)10.1039/c5ta00788g (DOI)000356022800044 ()
    Merknad

    Funding Agencies|Knut and Alice Wallenberg foundation; Marie Curie network Renaissance; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]

    Tilgjengelig fra: 2015-07-06 Laget: 2015-07-06 Sist oppdatert: 2017-12-04
    3. High performance PEDOT/lignin biopolymer composites for electrochemical supercapacitors
    Åpne denne publikasjonen i ny fane eller vindu >>High performance PEDOT/lignin biopolymer composites for electrochemical supercapacitors
    Vise andre…
    2016 (engelsk)Inngår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 4, nr 5, s. 1838-1847Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Developing sustainable organic electrode materials for energy storage applications is an urgent task. We present a promising candidate based on the use of lignin, the second most abundant biopolymer in nature. This polymer is combined with a conducting polymer, where lignin as a polyanion can behave both as a dopant and surfactant. The synthesis of PEDOT/Lig biocomposites by both oxidative chemical and electrochemical polymerization of EDOT in the presence of lignin sulfonate is presented. The characterization of PEDOT/Lig was performed by UV-Vis-NIR spectroscopy, FTIR infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, cyclic voltammetry and galvanostatic charge-discharge. PEDOT doped with lignin doubles the specific capacitance (170.4 F g(-1)) compared to reference PEDOT electrodes (80.4 F g(-1)). The enhanced energy storage performance is a consequence of the additional pseudocapacitance generated by the quinone moieties in lignin, which give rise to faradaic reactions. Furthermore PEDOT/Lig is a highly stable biocomposite, retaining about 83% of its electroactivity after 1000 charge/discharge cycles. These results illustrate that the redox doping strategy is a facile and straightforward approach to improve the electroactive performance of PEDOT.

    sted, utgiver, år, opplag, sider
    ROYAL SOC CHEMISTRY, 2016
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-125323 (URN)10.1039/c5ta10096h (DOI)000368839200035 ()
    Merknad

    Funding Agencies|Power Papers project from the Knut and Alice Wallenberg foundation; Wallenberg Scholar grant from the Knut and Alice Wallenberg foundation; Marie Curie network Renaissance (NA); European Research Council by Starting Grant Innovative Polymers for Energy Storage (iPes) [306250]; Basque Government

    Tilgjengelig fra: 2016-02-23 Laget: 2016-02-19 Sist oppdatert: 2017-11-30
  • 128.
    Akbar, Muhammad
    et al.
    COMSATS Univ Islamabad, Pakistan; Hubei Univ, Peoples R China.
    Alvi, Farah
    COMSATS Univ Islamabad, Pakistan.
    Shakir, Muhammad Imran
    Univ Calif Los Angeles, CA 90095 USA.
    Rehman, Saif Ur
    COMSATS Univ Islamabad, Pakistan.
    Rafique, Asia
    COMSATS Univ Islamabad, Pakistan.
    Mushtaq, Naveed
    COMSATS Univ Islamabad, Pakistan; Hubei Univ, Peoples R China.
    Raza, Rizwan
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Halvledarmaterial. Linköpings universitet, Tekniska fakulteten. COMSATS Univ Islamabad, Pakistan.
    Effect of sintering temperature on properties of LiNiCuZn-Oxide: a potential anode for solid oxide fuel cell2019Inngår i: MATERIALS RESEARCH EXPRESS, ISSN 2053-1591, Vol. 6, nr 10, artikkel-id 105505Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Crystal structure and surface morphology play vital role in the performance of Solid Oxide Fuel cells (SOFCs) anode. Sufficient electrocatalytic activity and high conductivity are the key requirements for anode to enhance the electrochemical capability. In current work, sintering temperature effects are investigated on the properties of advanced LiNiCuZn-Oxide based electrode for solid oxide fuel cells (SOFCs). The powders were prepared by simple solid-state reaction method was followed by sintering at different temperatures (700 degrees C-1200 degrees C). Moreover, various characterization techniques have been employed to investigate the sintering temperatures effects on the crystallite size, morphology, particle size, energy band gap and absorption peaks. The energy gap (Eg) was observed to increase from 2.94 eV to 3.32 eV and dc conductivity decreased from 9.084 Scm(-1) to 0.46 Scm(-1) by increasing sintering temperature from 700 degrees C to 1200 degrees C. Additionally, the best fuel cell performance of 0.90 Wcm(-2) was achieved for LiNiCuZn-Oxide sintered at 700 degrees C using H-2/air as a fuel and oxidant and it decreased to 0.17 Wcm(-2) for powders sintered at 1200 degrees C. Based on these results, we can conclude that 700 degrees C is the best optimum temperature for these chemical compositions, where all parameters of electrode are as per SOFCs requirement.

  • 129.
    Akbarian-Tefaghi, Ladan
    et al.
    Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London, UK.
    Akram, Harith
    Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London, UK.
    Johansson, Johannes
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Zrinzo, Ludvic
    Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London, UK.
    Kefalopoulou, Zinovia
    Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London, UK.
    Limousin, Patricia
    Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London, UK.
    Joyce, Eileen
    Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London, UK.
    Hariz, Marwan
    Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London, UK.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Foltynie, Tom
    Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London, UK.
    Refining the Deep Brain Stimulation Target within the Limbic Globus Pallidus Internus for Tourette Syndrome2017Inngår i: Stereotactic and Functional Neurosurgery, ISSN 1011-6125, E-ISSN 1423-0372, Vol. 95, nr 4, s. 251-258Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: Deep brain stimulation (DBS) in patients with severe, refractory Tourette syndrome (TS) has demonstrated promising but variable results thus far. The thalamus and anteromedial globus pallidus internus (amGPi) have been the most commonly stimulated sites within the cortico-striato thalamic circuit, but an optimal target is yet to be elucidated.

    OBJECTIVES: This study of 15 patients with long-term amGPi DBS for severe TS investigated whether a specific anatomical site within the amGPi correlated with optimal clinical outcome for the measures of tics, obsessive compulsive behaviour (OCB), and mood.

    METHODS: Validated clinical assessments were used to measure tics, OCB, quality of life, anxiety, and depression before DBS and at the latest follow-up (17-82 months). Electric field simulations were created for each patient using information on electrode location and individual stimulation parameters. A subsequent regression analysis correlated these patient-specific simulations to percentage changes in outcome measures in order to identify any significant voxels related to clinical improvement.

    RESULTS: A region within the ventral limbic GPi, specifically on the medial medullary lamina in the pallidum at the level of the AC-PC, was significantly associated with improved tics but not mood or OCB outcome.

    CONCLUSIONS: This study adds further support to the application of DBS in a tic-related network, though factors such as patient sample size and clinical heterogeneity remain as limitations and replication is required.

  • 130.
    Akerlind, C
    et al.
    Swedish Defence Research Agency.
    Arwin, Hans
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad optik. Linköpings universitet, Tekniska högskolan.
    Jakobsson, Fredrik
    Linköpings universitet, Institutionen för teknik och naturvetenskap. Linköpings universitet, Tekniska högskolan.
    Kariis, H
    Swedish Defence Research Agency.
    Järrendahl, Kenneth
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad optik. Linköpings universitet, Tekniska fakulteten.
    Optical properties and switching of a Rose Bengal derivative: A spectroscopic ellipsometry study2011Inngår i: THIN SOLID FILMS, ISSN 0040-6090, Vol. 519, nr 11, s. 3582-3586Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Optical properties in terms of the complex-valued dielectric function were determined for spin-coated films of a Rose Bengal derivative using variable angle of incidence spectroscopic ellipsometry in the visible and infrared wavelength regions. In addition, the thickness and roughness of the films were determined and related to the solution concentration of Rose Bengal. Switching between two different oxidation states of the Rose Bengal derivative was investigated. The two states were chemically induced by exposure to vapors of hydrochloric acid and ammonia, respectively. A substantial and reversible change of the optical properties of the films was observed.

  • 131.
    Akhlaghpasand, Hossein
    et al.
    Iran Univ Sci and Technol, Iran.
    Razavizadeh, S. Mohammad
    Iran Univ Sci and Technol, Iran.
    Björnson, Emil
    Linköpings universitet, Institutionen för systemteknik, Kommunikationssystem. Linköpings universitet, Tekniska fakulteten.
    Do, Tan Tai
    Ericsson AB, Sweden.
    Jamming Detection in Massive MIMO Systems2018Inngår i: IEEE Wireless Communications Letters, ISSN 2162-2337, E-ISSN 2162-2345, Vol. 7, nr 2, s. 242-245Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This letter considers the physical layer security of a pilot-based massive multiple-input multiple-output (MaMIMO) system in presence of a multi-antenna jammer. We propose a new jamming detection method that makes use of a generalized likelihood ratio tes

  • 132.
    Akram Hassan, Kahin
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Medie- och Informationsteknik. Linköpings universitet, Tekniska fakulteten.
    Rönnberg, Niklas
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Medie- och Informationsteknik. Linköpings universitet, Tekniska fakulteten.
    Forsell, Camilla
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Medie- och Informationsteknik. Linköpings universitet, Tekniska fakulteten.
    Johansson, Jimmy
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Medie- och Informationsteknik. Linköpings universitet, Tekniska fakulteten. Linköpings universitet, Centrum för klimatpolitisk forskning, CSPR.
    On the Performance of Stereoscopic Versus Monoscopic 3D Parallel Coordinates2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This work presents the results from an evaluation of stereoscopic versus monoscopic 3D parallel coordinates. The objective of the evaluation was to investigate if stereopsis increases user performance. The results show that stereoscopy has no effect at all on user performance compared to monoscopy. This result is important when it comes to the potential use of stereopsis within the information visualization community.

  • 133.
    Akram, Usman
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten.
    Metson, Genevieve
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten. Linköpings universitet, Centrum för klimatpolitisk forskning, CSPR.
    Quttineh, Nils-Hassan
    Linköpings universitet, Matematiska institutionen, Optimeringslära. Linköpings universitet, Tekniska fakulteten.
    Wennergren, Uno
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten.
    Closing Pakistan’s yield gaps through nutrient recycling2018Inngår i: Frontiers in Sustainable Food Systems, E-ISSN 2571-581X, s. 1-14, artikkel-id 00024Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Achieving food security will require closing yield gaps in many regions, including Pakistan. Although fertilizer subsidies have facilitated increased nitrogen (N) application rates, many staple crop yields have yet to reach their maximum potential. Considering that current animal manure and human excreta (bio-supply) recycling rates are low, there is substantial potential to increase the reuse of nutrients in bio-supply. We quantified 2010 crop N, phosphorus (P), and potassium (K) needs along with bio-supply nutrient availability for Pakistani districts, and compared these values to synthetic fertilizer use and costs. We found that synthetic fertilizer use combined with low bio-supply recycling resulted in a substantial gap between nutrient supply and P and K crop needs, which would cost 3 billion USD to fill with synthetic fertilizers. If all bio-supply was recycled, it could eliminate K synthetic fertilizer needs and decrease N synthetic fertilizer needs to 43% of what was purchased in 2010. Under a full recycling scenario, farmers would still require an additional 0.28 million tons of synthetic P fertilizers, costing 2.77 billion USD. However, it may not be prohibitively expensive to correct P deficiencies. Pakistan already spends this amount of money on fertilizers. If funds used for synthetic N were reallocated to synthetic P purchases in a full bio-supply recycling scenario, crop needs could be met. Most recycling could happen within districts, with only 6% of bio-supply requiring between-district transport when optimized to meet national N crop needs. Increased recycling in Pakistan could be a viable way to decrease yield gaps.

  • 134.
    Akram, Usman
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten.
    Quttineh, Nils-Hassan
    Linköpings universitet, Matematiska institutionen, Optimeringslära. Linköpings universitet, Tekniska fakulteten.
    Wennergren, Uno
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten.
    Tonderski, Karin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Metson, Genevieve
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten.
    Enhancing nutrient recycling from excreta to meet crop nutrient needs in Sweden - a spatial analysis2019Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, artikkel-id 10264Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Increased recycling of nutrient-rich organic waste to meet crop nutrient needs is an essential component of a more sustainable food system. However, agricultural specialization continues to pose a significant challenge to balancing crop nutrient needs and the nutrient supply from animal manure and human excreta locally. For Sweden, this study found that recycling all excreta (in 2007) could meet up to 75% of crop nitrogen and 81% of phosphorus needs, but that this would exceed crop potassium needs by 51%. Recycling excreta within municipalities could meet 63% of crop P nutrient needs, but large regional differences and imbalances need to be corrected to avoid over or under fertilizing. Over 50% of the total nitrogen and phosphorus in excreta is contained in just 40% of municipalities, and those have a surplus of excreta nutrients compared to crop needs. Reallocation of surpluses (nationally optimized for phosphorus) towards deficit municipalities, would cost 192 million USD (for 24 079 km of truck travel). This is 3.7 times more than the total NPK fertilizer value being transported. These results indicate that Sweden could reduce its dependence on synthetic fertilizers through investments in excreta recycling, but this would likely require valuing also other recycling benefits.

  • 135.
    Al Haji, Ghazwan
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Fowler, Scott
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Andersson Granberg, Tobias
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Smart traffic calming measures for smart cities - a pre-study2018Rapport (Annet vitenskapelig)
    Abstract [en]

    Traffic calming measures, such as speed bumps and elevated crossing points, are used to reduce speed, to prevent overtaking and generally contribute to a safer traffic situation. However, they might also cause increased response times for rescue vehicles (e.g. ambulances or fire trucks). An alternative to the conventional traffic calming measures is so-called smart traffic calming measures. These can determine when a vehicle approaches, whose journey should not be hindered, and adjust to allow for free passage for this vehicle.

    This report gives an overview of the problem, and some examples of smart  traffic calming measures are discussed. Special focus is put on the wireless communication necessary to detect emergency vehicles. Furthermore, existing challenges and possible solutions for traffic calming measures and the communication needed to make them smart are discussed.

  • 136.
    Alam, Syed Asad
    Linköpings universitet, Institutionen för systemteknik, Datorteknik. Linköpings universitet, Tekniska fakulteten.
    Techniques for Efficient Implementation of FIR and Particle Filtering2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    FIR filters occupy a central place many signal processing applications which either alter the shape, frequency or the sampling frequency of the signal. FIR filters are used because of their stability and possibility to have linear-phase but require a high filter order to achieve the same magnitude specifications as compared to IIR filters. Depending on the size of the required transition bandwidth the filter order can range from tens to hundreds to even thousands. Since the implementation of the filters in digital domain requires multipliers and adders, high filter orders translate to a large number of these arithmetic units for its implementation. Research towards reducing the complexity of FIR filters has been going on for decades and the techniques used can be roughly divided into two categories; reduction in the number of multipliers and simplification of the multiplier implementation. 

    One technique to reduce the number of multipliers is to use cascaded sub-filters with lower complexity to achieve the desired specification, known as FRM. One of the sub-filters is a upsampled model filter whose band edges are an integer multiple, termed as the period L, of the target filter's band edges. Other sub-filters may include complement and masking filters which filter different parts of the spectrum to achieve the desired response. From an implementation point-of-view, time-multiplexing is beneficial because generally the allowable maximum clock frequency supported by the current state-of-the-art semiconductor technology does not correspond to the application bound sample rate. A combination of these two techniques plays a significant role towards efficient implementation of FIR filters. Part of the work presented in this dissertation is architectures for time-multiplexed FRM filters that benefit from the inherent sparsity of the periodic model filters.

    These time-multiplexed FRM filters not only reduce the number of multipliers but lowers the memory usage. Although the FRM technique requires a higher number delay elements, it results in fewer memories and more energy efficient memory schemes when time-multiplexed. Different memory arrangements and memory access schemes have also been discussed and compared in terms of their efficiency when using both single and dual-port memories. An efficient pipelining scheme has been proposed which reduces the number of pipelining registers while achieving similar clock frequencies. The single optimal point where the number of multiplications is minimum for non-time-multiplexed FRM filters is shown to become a function of both the period, L and time-multiplexing factor, M. This means that the minimum number of multipliers does not always correspond to the minimum number of multiplications which also increases the flexibility of implementation. These filters are shown to achieve power reduction between 23% and 68% for the considered examples.

    To simplify the multiplier, alternate number systems like the LNS have been used to implement FIR filters, which reduces the multiplications to additions. FIR filters are realized by directly designing them using ILP in the LNS domain in the minimax sense using finite word length constraints. The branch and bound algorithm, a typical algorithm to implement ILP problems, is implemented based on LNS integers and several branching strategies are proposed and evaluated. The filter coefficients thus obtained are compared with the traditional finite word length coefficients obtained in the linear domain. It is shown that LNS FIR filters provide a better approximation  error compared to a standard FIR filter for a given coefficient word length.

    FIR filters also offer an opportunity in complexity reduction by implementing the multipliers using Booth or standard high-radix multiplication. Both of these multiplication schemes generate pre-computed multiples of the multiplicand which are then selected based on the encoded bits of the multiplier. In TDF FIR filters, one input data is multiplied with a number of coefficients and complexity can be reduced by sharing the pre-computation of the multiplies of the input data for all multiplications. Part of this work includes a systematic and unified approach to the design of such computation sharing multipliers and a comparison of the two forms of multiplication. It also gives closed form expressions for the cost of different parts of multiplication and gives an overview of various ways to implement the select unit with respect to the design of multiplexers.

    Particle filters are used to solve problems that require estimation of a system. Improved resampling schemes for reducing the latency of the resampling stage is proposed which uses a pre-fetch technique to reduce the latency between 50% to 95%  dependent on the number of pre-fetches. Generalized division-free architectures and compact memory structures are also proposed that map to different resampling algorithms and also help in reducing the complexity of the multinomial resampling algorithm and reduce the number of memories required by up to 50%.

    Delarbeid
    1. A unified approach to the design and implementation of computation sharing multipliers: Computation sharing multipliers
    Åpne denne publikasjonen i ny fane eller vindu >>A unified approach to the design and implementation of computation sharing multipliers: Computation sharing multipliers
    (engelsk)Manuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    A unified approach to the design and implementation of computation sharing multiplier based on Booth and standard high-radix multiplication schemes is presented here. Both of these multiplication schemes have various building blocks and one of which is the pre-computer which can be shared across a number of multiplications if the multiplicand to the multipliers is same, like in a transposed direct form (TDF) finitelength impulse response (FIR) filter. Closed form expressions to estimate the cost of different building blocks based on different schemes have been developed and analyzed in different dimensions. Standalone multipliers and as part of computation sharing in FIR filters and complex multipliers have been realized in hardware and synthesized using standard cell library.

    It is shown that apart from word length and filter length, the ratio  between the cost of implementing adders and multiplexers has an effect on the choice of optimal radix. The higher the ratio, the lower is the cost of implementing multiplexers which will benefit high radix. Higher radix will also benefit from computation sharing if the cost of one multiplication for it is less than the lower radix and it is shown that radix-16 Booth multiplier achieves lower area complexity and power consumption by an average of 7% and 17%, respectively.

    Emneord
    Computation sharing multipliers, standard high-radix multiplier, Booth multiplier, FIR filter
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-124194 (URN)
    Tilgjengelig fra: 2016-01-21 Laget: 2016-01-21 Sist oppdatert: 2016-02-02bibliografisk kontrollert
    2. On the implementation of time-multiplexed frequency-response masking filters
    Åpne denne publikasjonen i ny fane eller vindu >>On the implementation of time-multiplexed frequency-response masking filters
    2016 (engelsk)Inngår i: IEEE Transactions on Signal Processing, ISSN 1053-587X, E-ISSN 1941-0476, Vol. 64, nr 15, s. 3933-3944Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    The complexity of narrow transition band finite-length impulse response (FIR) filters is high and can be reduced by using frequency-response masking (FRM) techniques. These techniques use a combination of periodic model and, possibly periodic, masking filters. Time-multiplexing is in general beneficial since only rarely does the technology bound maximum obtainable clock frequency and the application determined required sample rate correspond. Therefore, architectures for time-multiplexed FRM filters that benefit from the inherent sparsity of theperiodic filters are introduced in this work.

    We show that FRM filters not only reduces the number of multipliers needed, but also have benefits in terms of memory usage. Despite the total amount of samples to be stored is larger for FRM, it results in fewer memory resources needed in FPGAs and more energy efficient memory schemes in ASICs. In total, the power consumption is significantly reduced compared to a single stage implementation. Furthermore, we show that the choice of the interpolation factor which gives the least complexity for the periodic model filter and subsequent masking filter(s) is a function of the time-multiplexing factor, meaning that the minimum number of multipliers not always correspond to the minimum number of multiplications. Both single-port and dual-port memories are considered and the involved trade-off in number of multipliers and memory complexity is illustrated. The results show that for FPGA implementation, the power reduction ranges from 23% to 68% for the considered examples.

    sted, utgiver, år, opplag, sider
    Institute of Electrical and Electronics Engineers (IEEE), 2016
    Emneord
    Frequency-response masking, FIR filter, FPGA, ASIC, time-multiplexing, memories
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-124190 (URN)10.1109/TSP.2016.2557298 (DOI)000379699800009 ()
    Merknad

    Vid tiden för disputation förelåg publikationen som manuskript

    Tilgjengelig fra: 2016-01-21 Laget: 2016-01-21 Sist oppdatert: 2017-11-30bibliografisk kontrollert
    3. Design of Finite Word Length Linear-Phase FIR Filters inthe Logarithmic Number System Domain
    Åpne denne publikasjonen i ny fane eller vindu >>Design of Finite Word Length Linear-Phase FIR Filters inthe Logarithmic Number System Domain
    2014 (engelsk)Inngår i: VLSI design (Print), ISSN 1065-514X, E-ISSN 1563-5171, Vol. 2014, nr 217495Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Logarithmic number system (LNS) is an attractive alternative to realize finite-length impulse response filters because ofmultiplication in the linear domain being only addition in the logarithmic domain. In the literature, linear coefficients are directlyreplaced by the logarithmic equivalent. In this paper, an approach to directly optimize the finite word length coefficients in theLNS domain is proposed. This branch and bound algorithm is implemented based on LNS integers and several different branchingstrategies are proposed and evaluated. Optimal coefficients in the minimax sense are obtained and compared with the traditionalfinite word length representation in the linear domain as well as using rounding. Results show that the proposed method naturallyprovides smaller approximation error compared to rounding. Furthermore, they provide insights into finite word length propertiesof FIR filters coefficients in the LNS domain and show that LNS FIR filters typically provide a better approximation error comparedto a standard FIR filter.

    sted, utgiver, år, opplag, sider
    Egypt: Hindawi Publishing Corporation, 2014
    Emneord
    Logarithmic Number System, FIR Filter, Integer Linear Programming, Branch and Bound
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-105861 (URN)10.1155/2014/217495 (DOI)
    Tilgjengelig fra: 2014-04-10 Laget: 2014-04-10 Sist oppdatert: 2017-12-05bibliografisk kontrollert
    4. Improved particle filter resampling architectures
    Åpne denne publikasjonen i ny fane eller vindu >>Improved particle filter resampling architectures
    (engelsk)Manuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    The most challenging aspect of particle filtering hardware implementation is the resampling step which replicates particles with large weights and discards those with small weights because it has a high latency and can only be partially executed in parallel with the other steps of particle filtering. To reduce the latency, an improved resampling scheme is proposed in this work which involves pre-fetching from the weight memory in parallel to the fetching of a value from a random function generator. Architectures for realizing the pre-fetch technique are also proposed. The trade-off between the latency reduction achieved by increasing the size of the pre-fetch memory and the architectural implementation complexity has been analyzed. Results show that a pre-fetch of five achieves the best area-latency trade-off while on average achieving an 85% reduction in the latency.

    We also propose a generic double multiplier architecture for resampling which avoids normalization divisions and makes the architecture equally efficient for non-powers-of-two number of particles as well as removes the need of explicitly ordering the random values for efficient multinomial resampling implementation. It is further improved by computing the cumulative sum of weights on-the-fly which helps in reducing the size of the weight memories by up to 50%.

    Emneord
    Particle filters, resampling algorithm, resampling architecture
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-124193 (URN)
    Tilgjengelig fra: 2016-01-21 Laget: 2016-01-21 Sist oppdatert: 2016-02-02bibliografisk kontrollert
  • 137.
    Alam, Syed Asad
    et al.
    Linköpings universitet, Institutionen för systemteknik, Datorteknik. Linköpings universitet, Tekniska fakulteten.
    Gustafsson, Oscar
    Linköpings universitet, Institutionen för systemteknik, Datorteknik. Linköpings universitet, Tekniska fakulteten.
    A unified approach to the design and implementation of computation sharing multipliers: Computation sharing multipliersManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    A unified approach to the design and implementation of computation sharing multiplier based on Booth and standard high-radix multiplication schemes is presented here. Both of these multiplication schemes have various building blocks and one of which is the pre-computer which can be shared across a number of multiplications if the multiplicand to the multipliers is same, like in a transposed direct form (TDF) finitelength impulse response (FIR) filter. Closed form expressions to estimate the cost of different building blocks based on different schemes have been developed and analyzed in different dimensions. Standalone multipliers and as part of computation sharing in FIR filters and complex multipliers have been realized in hardware and synthesized using standard cell library.

    It is shown that apart from word length and filter length, the ratio  between the cost of implementing adders and multiplexers has an effect on the choice of optimal radix. The higher the ratio, the lower is the cost of implementing multiplexers which will benefit high radix. Higher radix will also benefit from computation sharing if the cost of one multiplication for it is less than the lower radix and it is shown that radix-16 Booth multiplier achieves lower area complexity and power consumption by an average of 7% and 17%, respectively.

  • 138.
    Alam, Syed Asad
    et al.
    Linköpings universitet, Institutionen för systemteknik, Datorteknik. Linköpings universitet, Tekniska fakulteten.
    Gustafsson, Oscar
    Linköpings universitet, Institutionen för systemteknik, Datorteknik. Linköpings universitet, Tekniska fakulteten.
    Generalized Division-Free Architecture and Compact Memory Structure for Resampling in Particle Filters2015Inngår i: 2015 European Conference on Circuit Theory and Design (ECCTD), IEEE Press, 2015, s. 416-419Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The most challenging step of implementing particle filtering is the resampling step which replicates particles with large weights and discards those with small weights. In this paper, we propose a generic architecture for resampling which uses double multipliers to avoid normalization divisions and make the architecture  equally efficient for non-powers-of-two number of particles. Furthermore, the complexity of resampling is greatly affected by the size of memories used to store weights. We illustrate that by storing the original weights instead of their cumulative sum and calculating them online reduces the total complexity, in terms of area, ranging from 21% to 45%, while giving up to 50% reduction in memory usage.

  • 139.
    Alam, Syed Asad
    et al.
    Linköpings universitet, Institutionen för systemteknik, Datorteknik. Linköpings universitet, Tekniska fakulteten.
    Gustafsson, Oscar
    Linköpings universitet, Institutionen för systemteknik, Datorteknik. Linköpings universitet, Tekniska fakulteten.
    Improved particle filter resampling architecturesManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    The most challenging aspect of particle filtering hardware implementation is the resampling step which replicates particles with large weights and discards those with small weights because it has a high latency and can only be partially executed in parallel with the other steps of particle filtering. To reduce the latency, an improved resampling scheme is proposed in this work which involves pre-fetching from the weight memory in parallel to the fetching of a value from a random function generator. Architectures for realizing the pre-fetch technique are also proposed. The trade-off between the latency reduction achieved by increasing the size of the pre-fetch memory and the architectural implementation complexity has been analyzed. Results show that a pre-fetch of five achieves the best area-latency trade-off while on average achieving an 85% reduction in the latency.

    We also propose a generic double multiplier architecture for resampling which avoids normalization divisions and makes the architecture equally efficient for non-powers-of-two number of particles as well as removes the need of explicitly ordering the random values for efficient multinomial resampling implementation. It is further improved by computing the cumulative sum of weights on-the-fly which helps in reducing the size of the weight memories by up to 50%.

  • 140.
    Alam, Syed Asad
    et al.
    Linköpings universitet, Institutionen för systemteknik, Datorteknik. Linköpings universitet, Tekniska fakulteten.
    Gustafsson, Oscar
    Linköpings universitet, Institutionen för systemteknik, Datorteknik. Linköpings universitet, Tekniska fakulteten.
    On the implementation of time-multiplexed frequency-response masking filters2016Inngår i: IEEE Transactions on Signal Processing, ISSN 1053-587X, E-ISSN 1941-0476, Vol. 64, nr 15, s. 3933-3944Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The complexity of narrow transition band finite-length impulse response (FIR) filters is high and can be reduced by using frequency-response masking (FRM) techniques. These techniques use a combination of periodic model and, possibly periodic, masking filters. Time-multiplexing is in general beneficial since only rarely does the technology bound maximum obtainable clock frequency and the application determined required sample rate correspond. Therefore, architectures for time-multiplexed FRM filters that benefit from the inherent sparsity of theperiodic filters are introduced in this work.

    We show that FRM filters not only reduces the number of multipliers needed, but also have benefits in terms of memory usage. Despite the total amount of samples to be stored is larger for FRM, it results in fewer memory resources needed in FPGAs and more energy efficient memory schemes in ASICs. In total, the power consumption is significantly reduced compared to a single stage implementation. Furthermore, we show that the choice of the interpolation factor which gives the least complexity for the periodic model filter and subsequent masking filter(s) is a function of the time-multiplexing factor, meaning that the minimum number of multipliers not always correspond to the minimum number of multiplications. Both single-port and dual-port memories are considered and the involved trade-off in number of multipliers and memory complexity is illustrated. The results show that for FPGA implementation, the power reduction ranges from 23% to 68% for the considered examples.

  • 141.
    Alarcon, E I
    et al.
    Bio-nanomaterials Chemistry and Engineering Laboratory, Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Rm H5229, Ottawa, Canada.
    Vulesevic, B
    Bio-nanomaterials Chemistry and Engineering Laboratory, Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Rm H5229, Ottawa, Canada.
    Argawal, A
    Bio-nanomaterials Chemistry and Engineering Laboratory, Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Rm H5229, Ottawa, Canada.
    Ross, A
    Bio-nanomaterials Chemistry and Engineering Laboratory, Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Rm H5229, Ottawa, Canada.
    Bejjani, P
    Bio-nanomaterials Chemistry and Engineering Laboratory, Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Rm H5229, Ottawa, Canada.
    Podrebarac, J
    Bio-nanomaterials Chemistry and Engineering Laboratory, Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Rm H5229, Ottawa, Canada.
    Ravichandran, Ranjithkumar
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Phopase, Jaywant
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär fysik. Linköpings universitet, Tekniska fakulteten.
    Suuronen, E J
    Bio-nanomaterials Chemistry and Engineering Laboratory, Division of Cardiac Surgery, University of Ottawa Heart Institute, 40 Ruskin Street, Rm H5229, Ottawa, Canada.
    Griffith, May
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för cellbiologi. Linköpings universitet, Medicinska fakulteten.
    Coloured cornea replacements with anti-infective properties: expanding the safe use of silver nanoparticles in regenerative medicine.2016Inngår i: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 8, nr 12, s. 6484-6489Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Despite the broad anti-microbial and anti-inflammatory properties of silver nanoparticles (AgNPs), their use in bioengineered corneal replacements or bandage contact lenses has been hindered due to their intense yellow coloration. In this communication, we report the development of a new strategy to pre-stabilize and incorporate AgNPs with different colours into collagen matrices for fabrication of corneal implants and lenses, and assessed their in vitro and in vivo activity.

  • 142.
    Albahari, Alberto
    et al.
    Universidad de Malaga, Spain.
    Klofsten, Magnus
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Projekt, innovationer och entreprenörskap. Linköpings universitet, Tekniska fakulteten. Linköpings universitet, HELIX Competence Centre.
    Rubio-Romero, Juan Carlos
    Universidad de Malaga, Spain.
    Science and Technology Parks: A study of value creation for park tenants2019Inngår i: Journal of Technology Transfer, ISSN 0892-9912, E-ISSN 1573-7047, Vol. 44, nr 4, s. 1256-1272Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The literature on Science and Technology Parks (STPs) is growing rapidly and, despite the positive impact of STPs on firms found by many studies, it remains unclear how STPs create value for tenants. In this paper, we study the STP supply side through a case study in a Swedish region. We identify two components of the business support provided by parks: a configuration-oriented component, and a process-oriented component. The former refers to the static design of the business support, and the latter to the active, hands-on support provided by parks’ management. Both components must be planned carefully in order to deliver value to tenants. We also discuss some implications for policy and managers.

  • 143.
    Albani, Giorgia
    et al.
    University of Milano Bicocca, Italy; Ist Nazl Fis Nucl, Italy.
    Perelli Cippo, Enrico
    CNR, Italy.
    Croci, Gabriele
    University of Milano Bicocca, Italy; Ist Nazl Fis Nucl, Italy.
    Muraro, Andrea
    CNR, Italy.
    Schooneveld, Erik
    Rutherford Appleton Lab, England.
    Scherillo, Antonella
    Rutherford Appleton Lab, England.
    Hall-Wilton, Richard
    European Spallat Source ERIC, Sweden; Mittuniversitetet, Sweden.
    Kanaki, Kalliopi
    European Spallat Source ERIC, Sweden.
    Höglund, Carina
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten. European Spallat Source ERIC, Sweden.
    Hultman, Lars
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Birch, Jens
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Claps, Gerardo
    Ist Nazl Fis Nucl, Italy.
    Murtas, Fabrizio
    Ist Nazl Fis Nucl, Italy.
    Rebai, Marica
    University of Milano Bicocca, Italy; Ist Nazl Fis Nucl, Italy.
    Tardocchi, Marco
    CNR, Italy.
    Gorini, Giuseppe
    University of Milano Bicocca, Italy; CNR, Italy; Ist Nazl Fis Nucl, Italy.
    Evolution in boron-based GEM detectors for diffraction measurements: from planar to 3D converters2016Inngår i: Measurement science and technology, ISSN 0957-0233, E-ISSN 1361-6501, Vol. 27, nr 11, artikkel-id 115902Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The so-called He-3-crisis has motivated the neutron detector community to undertake an intense Ramp;D programme in order to develop technologies alternative to standard He-3 tubes and suitable for neutron detection systems in future spallation sources such as the European spallation source (ESS). Boron-based GEM (gas electron multiplier) detectors are a promising He-3-free technology for thermal neutron detection in neutron scattering experiments. In this paper the evolution of boron-based GEM detectors from planar to 3D converters with an application in diffraction measurements is presented. The use of 3D converters coupled with GEMs allows for an optimization of the detector performances. Three different detectors were used for diffraction measurements on the INES instrument at the ISIS spallation source. The performances of the GEM-detectors are compared with those of conventional He-3 tubes installed on the INES instrument. The conceptual detector with the 3D converter used in this paper reached a count rate per unit area of about 25% relative to the currently installed He-3 tube. Its timing resolution is similar and the signal-to-background ratio (S/B) is 2 times lower.

  • 144.
    Albarracín, Lluís
    et al.
    Universitat Autònoma de Barcelona.
    Bergman Ärlebäck, Jonas
    Linköpings universitet, Matematiska institutionen, Matematik och tillämpad matematik. Linköpings universitet, Tekniska fakulteten.
    Civil, Elisabeth
    Universitat Autònoma de Barcelona.
    Gorgorió, Núria
    Universitat Autònoma de Barcelona.
    Extending Modelling Activity Diagrams as a tool to characterise mathematical modelling processes2019Inngår i: The Montana Mathematics Enthusiast, ISSN 1551-3440, E-ISSN 1551-3440, Vol. 16, nr 1-2, artikkel-id 10Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper, we present a qualitative study in which we analyse the video-recordings of four groups of students solving Fermi Problems. Previous studies show that Secondary School students solve this type of problems using complex problem solving processes and developing mathematical models. In order to analyse the students’ problem solving processes, so-called Modelling Activity Diagrams were used. The results of the present study demonstrate that solving Fermi problems is a complex matter, and that some of the theoretical tools used in the field of Mathematical Education fail to adequately reflect this level of complexity. In addition, Modelling Activity Diagrams are presented as a more detailed analysis tool to characterise student choices and actions, as well as to make the structure of the Fermi problem addressed more visible.

  • 145.
    Albertsson, Sarah
    et al.
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Tekniska fakulteten. SICS East Swedish ICT AB, Linköping, Sweden.
    Rennes, Evelina
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Tekniska fakulteten. SICS East Swedish ICT AB, Linköping, Sweden.
    Jönsson, Arne
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Filosofiska fakulteten. SICS East Swedish ICT AB, Linköping, Sweden.
    Similarity-Based Alignment of Monolingual Corpora for Text Simplification2016Inngår i: CL4LC 2016 - Computational Linguistics for Linguistic Complexity: Proceedings of the Workshop, The COLING 2016 Organizing Committee , 2016, s. 154-163Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Comparable or parallel corpora are beneficial for many NLP tasks.  The automatic collection of corpora enables large-scale resources, even for less-resourced languages, which in turn can be useful for deducing rules and patterns for text rewriting algorithms, a subtask of automatic text simplification. We present two methods for the alignment of Swedish easy-to-read text segments to text segments from a reference corpus.  The first method (M1) was originally developed for the task of text reuse detection, measuring sentence similarity by a modified version of a TF-IDF vector space model. A second method (M2), also accounting for part-of-speech tags, was devel- oped, and the methods were compared.  For evaluation, a crowdsourcing platform was built for human judgement data collection, and preliminary results showed that cosine similarity relates better to human ranks than the Dice coefficient. We also saw a tendency that including syntactic context to the TF-IDF vector space model is beneficial for this kind of paraphrase alignment task.

  • 146.
    Albinsson, L.
    et al.
    Swedish National Forensic Centre - NFC, Linköping, Sweden.
    Hedman, J.
    Swedish National Forensic Centre - NFC, Linköping, Sweden.
    Ansell, Ricky
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten. Swedish National Forensic Centre - NFC, Linköping, Sweden.
    Mixed DNA profiles from single-donors2015Inngår i: Abstract book, 7th European Academy of Forensic Science, EAFS, Prag, Tjeckien, 2015, 2015, s. 538-Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Mosaicism and chimerism in individuals can complicate the interpretation and even lead to misinterpretation of DNA profiles in forensic casework. If a person has different DNA profiles in different tissue types, i.e. a true chimaera, wrongful exclusions can be made. Additionally, mixed chimaeras can have DNA profiles that may be mistaken for mixtures. We have set-up automatic DNA databasing processes to handle atypical single-donor DNA profiles, i.e. profiles having one or several “extra” alleles.

    Studying all reference samples analysed at NFC from 2006 until spring 2014, 2‰ of the samples showed atypical DNA profiles. To be able to set routines for handling these DNA profiles, each one was manually searched in CODIS with adjusted settings, to evaluate the frequency of false-positive hits. To tag these profiles in LIMS a new result status was implemented. Additionally, all such DNA profiles must be confirmed by analysing at least two discrete samples. In LIMS, the results are manually recorded to compose of all alleles from the samples from a suspect, i.e. containing most possible genetic information. LIMS automatically categorises the atypical DNA profiles with a special CODIS index, called “Multi-allelic offender”. The first time an atypical profile is searched, the matches are manually investigated. If a match is false, its disposition will be set to “no match” to prevent this from occurring in future searches. Automatic searches will then be performed in every day routine with moderate stringency, allowing the atypical DNA profile to match either a genotype or a mixture. If the match is true, a match-report will be created and sent to the police from the LIMS.

     

  • 147.
    Albouy, Camille
    et al.
    IFREMER, France.
    Archambault, Philippe
    Univ Laval, Canada.
    Appeltans, Ward
    UNESCO, Belgium.
    Araujo, Miguel B.
    CSIC, Spain; Univ Evora, Portugal; Univ Copenhagen, Denmark.
    Beauchesne, David
    Univ Quebec Rimouski, Canada.
    Cazelles, Kevin
    Univ Guelph, Canada.
    Cirtwill, Alyssa
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten. Univ Canterbury, New Zealand.
    Fortin, Marie-Josee
    Univ Toronto, Canada.
    Galiana, Nuria
    CNRS, France.
    Leroux, Shawn J.
    Mem Univ, Canada.
    Pellissier, Loik
    Swiss Fed Inst Technol, Switzerland; Swiss Fed Res Inst WSL, Switzerland.
    Poisot, Timothee
    Univ Montreal, Canada; McGill Univ, Canada.
    Stouffer, Daniel B.
    Univ Canterbury, New Zealand.
    Wood, Spencer A.
    Univ Washington, WA 98195 USA.
    Gravel, Dominique
    Univ Montreal, Canada; Univ Sherbrooke, Canada.
    The marine fish food web is globally connected2019Inngår i: Nature Ecology & Evolution, E-ISSN 2397-334X, Vol. 3, nr 8, s. 1153-+Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The productivity of marine ecosystems and the services they provide to humans are largely dependent on complex interactions between prey and predators. These are embedded in a diverse network of trophic interactions, resulting in a cascade of events following perturbations such as species extinction. The sheer scale of oceans, however, precludes the characterization of marine feeding networks through de novo sampling. This effort ought instead to rely on a combination of extensive data and inference. Here we investigate how the distribution of trophic interactions at the global scale shapes the marine fish food web structure. We hypothesize that the heterogeneous distribution of species ranges in biogeographic regions should concentrate interactions in the warmest areas and within species groups. We find that the inferred global metaweb of marine fish-that is, all possible potential feeding links between co-occurring species-is highly connected geographically with a low degree of spatial modularity. Metrics of network structure correlate with sea surface temperature and tend to peak towards the tropics. In contrast to open-water communities, coastal food webs have greater interaction redundancy, which may confer robustness to species extinction. Our results suggest that marine ecosystems are connected yet display some resistance to perturbations because of high robustness at most locations.

  • 148.
    Albrektsson, Jörgen
    Linköpings universitet, Institutionen för systemteknik, Fordonssystem. Linköpings universitet, Tekniska fakulteten.
    Optimisation of Off-Road Transport Missions2018Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Mines, construction sites, road construction and quarries are examples of applications where construction equipment are used. In a production chain consisting of several construction machines working together, the work needs to be optimised and coordinated to achieve an environmental friendly, energy efficient and productive production. Recent rapid development within positioning services, telematics and human machine interfaces (HMI) opens up for control of individual machines and optimisation of transport missions where several construction machines co-operate.

    The production chain on a work site can be split up in different sub-tasks of which some can be transport missions. Taking off in a transport mission where one wheel loader ("loader" hereinafter) and two articulated haulers ("haulers" hereinafter) co-operate to transport material at a set production rate [ton/h], a method for fuel optimal control is developed. On the mission level, optimal cycle times for individual sub-tasks such as wheel loader loading, hauler transport and hauler return, are established through the usage of Pareto fronts.

    The haulers Pareto fronts are built through the development of a Dynamic Programming (DP) algorithm that trades fuel consumption versus cycle time for a road stretch by means of a time penalty constant. Through varying the time penalty constant n number of times, discrete fuel consumption - cycle time values can be achieved, forming the Pareto front. At a later stage, the same DP algorithm is used to generate fuel optimal vehicle speed and gear trajectories that are used as control signals for the haulers. Input to the DP algorithm is the distance to be travelled, road inclination, rolling resistance coefficient and a max speed limit to avoid unrealistic optimisation results.

    Thus, a method to describe the road and detect the road related data is needed to enable the optimisation. A map module is built utilising an extended Kalman Filter, Rauch-Tung-Striebel smoother and sensor fusion to merge data and estimate parameters not observable by sensors. The map module uses a model of the vehicle, sensor signals from a GPS or GNSS sensor and machine sensors to establish a map of the road.

    The wheel loader Pareto front is based on data developed in previous research combined with Volvo in-house data. The developed optimisation algorithms are implemented on a PC and in an interactive computer tablet based system. A human machine interface is created for the tablet, guiding the operators to follow the optimal control signals, which is speed for the haulers and cycle time for the loader. To evaluate the performance of the system it is tested in real working conditions.

    The contributions develop algorithms, set up a demo mission control system and carry out experiments. Altogether rendering in a platform that can be used as a base for a future design of an off-road transport mission control system.

    Delarbeid
    1. Road estimation and fuel optimal control of an off-road vehicle
    Åpne denne publikasjonen i ny fane eller vindu >>Road estimation and fuel optimal control of an off-road vehicle
    2017 (engelsk)Inngår i: Proceedings of the 3rd International Conference on Vehicle Technology and Intelligent Transport Systems, SciTePress, 2017, s. 58-67Konferansepaper, Publicerat paper (Fagfellevurdert)
    sted, utgiver, år, opplag, sider
    SciTePress, 2017
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-142731 (URN)10.5220/0006247200580067 (DOI)978-989-758-242-4 (ISBN)
    Konferanse
    3rd International Conference on Vehicle Technology and Intelligent Transport Systems, VEHITS 2017, April 22-24, 2017, in Porto, Portugal
    Tilgjengelig fra: 2018-04-03 Laget: 2018-04-03 Sist oppdatert: 2018-11-22
    2. Fuel Optimal Control of an Articulated Hauler Utilising a Human Machine Interface
    Åpne denne publikasjonen i ny fane eller vindu >>Fuel Optimal Control of an Articulated Hauler Utilising a Human Machine Interface
    2019 (engelsk)Inngår i: Smart Cities, Green Technologies, and Intelligent Transport Systems / [ed] Donnellan, Brian; Klein, Cornel; Helfert, Markus; Gusikhin, Oleg; Pascoal, António, Springer International Publishing , 2019, s. 190-208Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    Utilising optimal control presents an opportunity to increase the fuel efficiency in an off-road transport mission conducted by an articulated hauler. A human machine interface (HMI) instructing the hauler operator to follow the fuel optimal vehicle speed trajectory has been developed and tested in real working conditions. The HMI implementation includes a Dynamic Programming based method to calculate the optimal vehicle speed and gear shift trajectories. Input to the optimisation algorithm is road related data such as distance, road inclination and rolling resistance. The road related data is estimated in a map module utilising an Extended Kalman Filter (EKF), a Rauch-Tung-Striebel smoother and a data fusion algorithm. Two test modes were compared: (1) The hauler operator tried to follow the optimal vehicle speed trajectory as presented in the HMI and (2) the operator was given a constant target speed to follow. The objective of the second test mode is to achieve an approximately equal cycle time as for the optimally controlled transport mission, hence, with similar productivity. A small fuel efficiency improvement was found when the human machine interface was used.

    sted, utgiver, år, opplag, sider
    Springer International Publishing, 2019
    Serie
    Communications in Computer and Information Science book series (CCIS), ISSN 1865-0929, E-ISSN 1865-0937 ; 921
    Emneord
    Off-road, Construction equipment, Human machine interface, Optimal control, Dynamic programming, Kalman filters
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-153311 (URN)10.1007/978-3-030-02907-4_10 (DOI)978-3-030-02906-7 (ISBN)978-3-030-02907-4 (ISBN)
    Konferanse
    6th International Conference, SMARTGREENS 2017 and Third International Conference, VEHITS 2017, Porto, Portugal, April 22–24, 2017
    Tilgjengelig fra: 2018-12-12 Laget: 2018-12-12 Sist oppdatert: 2018-12-12
    3. Fuel optimal control of an off-road transport mission
    Åpne denne publikasjonen i ny fane eller vindu >>Fuel optimal control of an off-road transport mission
    2018 (engelsk)Inngår i: 2018 IEEE International Conference on Industrial Technology (ICIT), 2018, s. 175-180Konferansepaper, Publicerat paper (Fagfellevurdert)
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-151856 (URN)10.1109/ICIT.2018.8352172 (DOI)978-1-5090-5949-2 (ISBN)
    Konferanse
    2018 IEEE International Conference on Industrial Technology (ICIT), 19-22 Feb.,Lyon, France
    Tilgjengelig fra: 2018-10-06 Laget: 2018-10-06 Sist oppdatert: 2018-11-22
  • 149.
    Albrektsson, Jörgen
    et al.
    Linköpings universitet, Institutionen för systemteknik, Fordonssystem. Linköpings universitet, Tekniska fakulteten. Volvo Construction Equipment, Eskilstuna, Sweden.
    Åslund, Jan
    Linköpings universitet, Institutionen för systemteknik, Fordonssystem. Linköpings universitet, Tekniska fakulteten.
    Fuel Optimal Control of an Articulated Hauler Utilising a Human Machine Interface2019Inngår i: Smart Cities, Green Technologies, and Intelligent Transport Systems / [ed] Donnellan, Brian; Klein, Cornel; Helfert, Markus; Gusikhin, Oleg; Pascoal, António, Springer International Publishing , 2019, s. 190-208Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Utilising optimal control presents an opportunity to increase the fuel efficiency in an off-road transport mission conducted by an articulated hauler. A human machine interface (HMI) instructing the hauler operator to follow the fuel optimal vehicle speed trajectory has been developed and tested in real working conditions. The HMI implementation includes a Dynamic Programming based method to calculate the optimal vehicle speed and gear shift trajectories. Input to the optimisation algorithm is road related data such as distance, road inclination and rolling resistance. The road related data is estimated in a map module utilising an Extended Kalman Filter (EKF), a Rauch-Tung-Striebel smoother and a data fusion algorithm. Two test modes were compared: (1) The hauler operator tried to follow the optimal vehicle speed trajectory as presented in the HMI and (2) the operator was given a constant target speed to follow. The objective of the second test mode is to achieve an approximately equal cycle time as for the optimally controlled transport mission, hence, with similar productivity. A small fuel efficiency improvement was found when the human machine interface was used.

  • 150.
    Albrektsson, Jörgen
    et al.
    Linköpings universitet, Institutionen för systemteknik, Fordonssystem. Linköpings universitet, Tekniska fakulteten.
    Åslund, Jan
    Linköpings universitet, Institutionen för systemteknik, Fordonssystem. Linköpings universitet, Tekniska fakulteten.
    Fuel optimal control of an off-road transport mission2018Inngår i: 2018 IEEE International Conference on Industrial Technology (ICIT), 2018, s. 175-180Konferansepaper (Fagfellevurdert)
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