Change search
Refine search result
949596979899100 4801 - 4850 of 5318
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the 'Create feeds' function.
  • 4801.
    Turner, Anthony
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Reflections on Biosensors 20162017In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 88Article in journal (Other academic)
    Abstract [en]

    n/a

  • 4802.
    Turner, Anthony
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Single-molecule electroanalysis and printed electronic systems.2017Conference paper (Refereed)
  • 4803.
    Turner, Anthony
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    The paper potentiostat2015In: 4th International Conference on Bio-Sensing Technology, 10-13 May 2015, Lisbon, Portugal., Elsevier, 2015Conference paper (Refereed)
    Abstract [en]

    This presentation will focus on meeting current challenges in decentralised diagnostics by using amperometric and votammetric systems printed on paper or plastic substrates to deliver inexpensive instruments for a wide range of electroanalytical applications. This approach combines the sophistication of advanced electrochemical biosensors with a simple manufacturing technique to create a use-and-throw instrument. The system is manufactured under ambient conditions. All interconnections are printed and an anisotropic conductive glue is used for interconnection between the chip and conductors. A screen-printed manganese dioxide battery and a vertical electrochromic display are incorporated in the instrument. The display is paper-like in the sense that it works in reflective mode, that is, no backlight is used to light up the pixels. This integrated biosensing platform forms a workhorse in our hands for a variety of diagnostic systems including enzyme electrodes for multi-parametric diabetes monitoring and for the management of chronic kidney disease, electrochemical sensors for enzymes such as G6-P or amylase (a marker for stress), label-free affinity sensors for cancer markers and heart disease, aptasensors for cancer cells, DNA Sensors and robust devices based on imprinted and smart polymers. Using these technologies, we envision over-the-counter paper instruments for self-diagnosis of common diseases such as diabetes, kidney disease and urinary tract infection; inexpensive devices for use by caregivers or paramedics such as the ”Stressometer” or heart attack indicators; home kits to support people after transplant surgery or cancer treatment, smart cartons for pharmaceuticals; pocket tests for allergens, food toxicity, drinking water etc. and strips or patches that communicate with mobile telecommunications. Realisation of these paradigm-changing new products requires the effective harnessing of emerging technology, inspired vision from clinical partners or others “users” and leading-edge engineering to design and produce functional systems in appropriate volumes at the right cost.

  • 4804.
    Turner, Anthony
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Towards single molecule detection with simple printed instruments2016In: American Advanced Materials Congress, India: VBRI Press , 2016Conference paper (Other academic)
    Abstract [en]

    There is now intense pressure on healthcare systems worldwide that will inevitably lead to radical change. Partic ular excitement surrounds the  concept of  wearable  and internetworked analytical  devices, but current technology generally  falls far short of the sensitivity  and  specificity  required  to  make  further  inroads  into  understanding  complex  biochemistries and  appl ying  this knowledge  to  improving  quality  of  life . Most  devices realised to  date , utilise  derived  information  from  physical  sensors  and cannot begin to resolve  the  complexity that can be  revealed by  molecular sensors. A  notable  exception is the  use  of  biose nsors for  continuous in  vivo monitoring and  control  of  diabetes,  but  progressing  beyond  this  important  innovation  requires  a  step change  in  thinking,  since  most  other  desirable  analytes  offer  greater  challenges  than  glucose  in  terms  of the  degree  of discri mination demanded or the low concentrations present in unprocessed samples . Recent ad vances in single - molecule sens ing enable  molecular  counting,  thus  heralding  an  entirely  new ,  calibration - free quantitative  approach able  to  properly  discriminate the  heter ogeneities  implicit  in  living  systems. Rare  and  unusual  events  can  be  distinguished  from  the  noise  a ssociated  with ensemble  studies  and  i ndividual  inter - and  intra - molecular  events  can  be  studied  in  detail . Combining  this technique with  the simplicity  of  e lectroanalysis  and  recent  advances  in  printed  electronics  allows  us  to  conceive  of  powerful  analytical  tools  that could  be  mass  produced  in  a  variety  of  form  factors , suitable  for  emerging  markets  based  around  next  generation  intelligent systems. Add  to  th is  appropriate  sampling  technology  and  we  may  finally  be  able  to  access  the  multifarious  biomarkers  that could allow us to better maintain health in the face of genetic, nutritional and environmental factors, and to personalise tr eatment of  disease  with  ta ilored  pha r maceuticals  and  bioelectronic  medicine. This  presentation  will  review  our  recent  work  on  single molecule  electrochemistry,  the  design  of  printed  electroanalytical  instruments  and  new  approaches  to  minimally  invasive sampling and will speculate o n possible future developments based on combining these leading edge technologies.

  • 4805.
    Turner, Anthony
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Using polymers to make smarter biosensor systems2015In: Smart Materials at Biointerfaces, 2015Conference paper (Other academic)
  • 4806.
    Turner, Anthony
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Gifford, Raeann
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Holub, Douglas
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Method and Device for Measuring EnzymaticActivity of Polysaccharide-Hydrolysing Enzymes.2016Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    A device and method for detecting and/or measuring a polysaccharide-hydrolysing activity of an enzyme and/or quantifying the amount of the enzyme in a sample employs a complex of a polysaccharide that is hydrolysable by the enzyme and an electrically active signal species or progenitor thereof such that action of the enzyme on the complex causes liberation of the signal species or progenitor.  Thus enzyme activity leads to free signal species which can be detected and quantified electrically.

  • 4807.
    Turner, Anthony P.F.
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Paper potentiostats for bioelectrochemistry2015In: Program of the XXIII International Symposium on Bioelectrochemistry and Bioenergetics of the Bioelectrochemical Society. 14-18 June, 2015. Malmö, Sweden, Lausenne: Bioelectrochemical Society , 2015, 166-166 p.Conference paper (Other academic)
    Abstract [en]

    This presentation will focus on meeting current challenges in decentralised diagnostics by using amperometric and votammetric systems printed on paper or plastic substrates to deliver inexpensive instruments for a wide range of electroanalytical applications. This approach combines the sophistication of advanced electrochemical biosensors with a simple manufacturing technique to create a use-and-throw instrument. A key driver for next-generation electroanalytical devices is rapid, convenient and easy ways to measure our body chemistries at the genomic, proteomic and metabolomic levels. We are targeting fully-integrated platforms such as all-printed biosensing systems, integrated sampling and wearable devices. Further development will result in cost reduction and a diversity of formats such as point-of-care tests, smart packaging, telemetric paper strips and print-on-demand analytical devices. These platforms form workhorses in our hands for a variety of diagnostic systems including enzyme electrodes for multi-parametric diabetes monitoring and for the management of chronic kidney disease, electrochemical sensors for enzymes such as G6-P or amylase (a marker for stress), label-free affinity sensors for cancer markers and heart disease, aptasensors for cancer cells, DNA Sensors and robust devices based on imprinted and smart polymers. Using these technologies, we envision over-the-counter paper instruments for self-diagnosis of common diseases such as diabetes, kidney disease and urinary tract infection; inexpensive devices for use by caregivers or paramedics such as the ”Stressometer” or heart attack indicators; home kits to support people after transplant surgery or cancer treatment, smart cartons for pharmaceuticals; pocket tests for allergens, food toxicity, drinking water etc. and strips or patches that communicate with mobile telecommunications. Realisation of these paradigm-changing new products requires the effective harnessing of emerging technology, inspired vision from clinical partners or others “users” and leading-edge engineering to design and produce functional systems in appropriate volumes at the right cost.

  • 4808.
    Tvingstedt, Kristofer
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Vandewal, Koen
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Zhang, Fengling
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    On the Dissociation Efficiency of Charge Transfer Excitons and Frenkel Excitons in Organic Solar Cells: A Luminescence Quenching Study2010In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 114, no 49, 21824-21832 p.Article in journal (Refereed)
    Abstract [en]

    The field dependence of photocurrent found in many organic solar cells is a significant and detrimental setback for internal quantum efficiency. In this work we study the important contribution to this field dependence due to the dissociation efficiency of the weakly bound interfacial charge transfer (CT) state, crucial for organic bulk heterojunction solar cells. Three different donor polymers and two different acceptors are examined, and their respective dissociation characteristics are evaluated by photoluminescence (PL) quenching, both for Frenkel excitons and for the intermolecular charge transfer excitons. We observe that while the field-dependent photocurrent for pure polymers does correlate well with quenching efficiency, the CT exciton quenching from the blend generally displays a less pronounced correlation with extracted photocurrent. We further note that while the electroluminescence and photoluminescence of the pure polymer are identical, we observe a red shift for the blend electroluminescence. This indicates that lower energetic states, not visible in PL, are available in the blend. The emissive state of the blends probed by PL is therefore proposed to originate from sites that are involved in photocurrent generation to a lesser extent.

  • 4809.
    Tybrandt, Klas
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Exploring the potential of ionic bipolar diodes for chemical neural interfaces2017In: Soft Matter, ISSN 1744-683X, E-ISSN 1744-6848, Vol. 13, no 44, 8171-8177 p.Article in journal (Refereed)
    Abstract [en]

    Technology interfaces which can imitate the chemically specific signaling of nervous tissues are attractive for studying and developing therapies for neurological disorders. As the signaling in nervous tissue is highly spatiotemporal in nature, an interfacing technology should provide local neurotransmitter release in the millisecond range. To obtain such a speed, the neurotransmitters must be stored close to the release point, while avoiding substantial passive leakage. Here we theoretically investigate whether ionic bipolar diodes can be used for this purpose. We find that if a sufficiently large reverse potential is applied, the passive leakage can be suppressed to negligible levels due to the high local electric field within the bipolar diode. The influences of various design parameters are studied to determine the optimal design and operation. Finally, the delivery speed of the component is evaluated using time-dependent simulations, which show that the release of neurotransmitters to physiologically relevant concentrations can be achieved in less than 10 ms. Altogether, the results suggest that ionic bipolar diodes constitute a highly attractive technology for achieving high speed low leakage addressable delivery circuits for neural interfaces.

  • 4810.
    Tybrandt, Klas
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Zozoulenko, Igor
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Chemical potential-electric double layer coupling in conjugated polymer-polyelectrolyte blends2017In: Science Advances, ISSN 0036-8156, E-ISSN 2375-2548, Vol. 3, no 12, eaao3659Article in journal (Refereed)
    Abstract [en]

    Conjugated polymer-polyelectrolyte blends combine and couple electronic semiconductor functionality with selective ionic transport, making them attractive as the active material in organic biosensors and bioelectronics, electrochromic displays, neuromorphic computing, and energy conversion and storage. Although extensively studied and explored, fundamental knowledge and accurate quantitative models of the coupled ion-electron functionality and transport are still lacking to predict the characteristics of electrodes and devices based on these blends. We report on a two-phase model, which couples the chemical potential of the holes, in the conjugated polymer, with the electric double layer residing at the conjugated polymer-polyelectrolyte interface. The model reproduces a wide range of experimental charging and transport data and provides a coherent theoretical framework for the system as well as local electrostatic potentials, energy levels, and charge carrier concentrations. This knowledge is crucial for future developments and optimizations of bioelectronic and energy devices based on the electronic-ionic interaction within these materials.

  • 4811.
    Tyler, Torbjörn
    et al.
    Biological Museums, Dept of Biology, Lund Univ., Lund, Sweden.
    Karlsson, Thomas
    Swedish Museum of Natural History, Stockholm, Sweden.
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Sahlin, Ullrika
    Centre of Environmental and Climate Research, Lund Univ., Lund, Sweden.
    Sundberg, Sebastian
    The Swedish Species Information Centre, Swedish Univ. of Agricultural Sciences, Uppsala, Sweden.
    Invasive plant species in the Swedish flora: Developing criteria and definitions, and assessing the invasiveness of individual taxa2015In: Nordic Journal of Botany, ISSN 0107-055X, E-ISSN 1756-1051, Vol. 33, no 3, 300-317 p.Article in journal (Refereed)
    Abstract [en]

    In a north European context, identifying invasive species is far from trivial because the vegetation has been influenced by human activities for thousands of years. New species have immigrated continuously since the end of the last glaciation, both spontaneously and through direct or indirect help by man. Still, newly immigrated species may be problematic in a nature conservation context and may harm biodiversity, and cause changes in ecosystem services. In this study, all 721 presently established vascular plant and bryophyte taxa known to have been introduced to, or to have immigrated to, Sweden since the year 1700 are assessed for their invasive potential. The assessment is based on six components considered relevant for their invasiveness: 1) ability to compete in natural vegetation, 2) ability to form dense populations, 3) realized dispersal ability, 4) gene flow to native relatives, 5) time since immigration and 6) distance to their native range. Although the relative importance of these components is context dependent, a compound general index of invasive concern is proposed and calculated for all taxa. The index of invasive concern is validated by comparing it to assessments by a Bayesian Belief Network in which the influences of the same six components are assigned by expert opinions. In addition, rough estimates of the present-day abundance of each taxon in Sweden are presented. The origin, biology and possible impact of the 150 taxa with the highest index values are discussed. Based on the index of invasive concern, Campylopus introflexus, Epilobium adenocaulon, E. ciliatum, Rosa rugosa, Lamiastrum galeobdolon subsp. argentatum, Orthodontium lineare, Solidago canadensis, Calystegia sepium subsp. spectabilis, Rubus armeniacus and Prunus serotina are identified as the ten most problematic alien vascular plant and bryophyte taxa in Sweden.

  • 4812.
    Tälle, Malin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Deák, Balázs
    MTA-DE Biodiversity and Ecosystem Services Research Group, Egytem tér 1, Debrecen H-4032, Hungary.
    Poschlod, Peter
    Ecology and Conservation Biology, Institute of Plant Sciences, University of Regensburg, D-93040 Regensburg, Germany.
    Valkó, Orsolya
    University of Debrecen, Department of Ecology, P.O. Box 71, Debrecen H-4010, Hungary.
    Westerberg, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Grazing vs. mowing: A meta-analysis of biodiversity benefits forgrassland management2016In: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 222, 200-212 p.Article in journal (Refereed)
    Abstract [en]

    To maintain the high biodiversity of semi-natural grasslands, management by grazing or mowing isneeded. Given the limited resources and few remaining areas, the best management method should beused. However, only a few studies comparing the effects of mowing and grazing on grassland biodiversityexists. Therefore, the goal of the present review was to extract as much data as possible from theliterature and evaluate them using a meta-analysis approach. We searched scientific and grey literaturefor studies comparing the effects of grazing and annual mowing on outcomes relevant for biodiversityconservation. We identified 35 relevant studies on grazing and annual mowing that provided datasuitable for the meta-analysis. We found that grazing generally had a more positive effect on theconservation value of semi-natural grasslands compared to mowing, but effect sizes were generally smallto moderate for most contrasts. Furthermore, effects varied across some grassland characteristics e.g. fordifferent grassland types, with grazing and mowing having a similar effect or mowing having a morepositive effect in certain cases. Our results suggest, that in most cases grazing should be the preferredmanagement method when managing for grassland conservation.

  • 4813.
    Tälle, Malin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Fogelfors, Håkan
    Dept of Crop Production Ecology, Swedish Univ. of Agricultural Sciences, Box 7043, SE-750 07 Uppsala, Sweden.
    Westerberg, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    The conservation benefit of mowing vs grazing for management ofspecies-rich grasslands: a multi-site, multi-year field experiment2015In: Nordic Journal of Botany, ISSN 0107-055X, E-ISSN 1756-1051, Vol. 33, no 6, 761-768 p.Article in journal (Refereed)
    Abstract [en]

    Species-rich semi-natural grasslands in Europe are becoming more fragmented and many species that depend on thishabitat type are rare and threatened today. Management methods like mowing and grazing are needed to preserve remaininggrasslands. Because management is costly it is important to use the most cost-effective as well as the most beneficialmanagement method, but few studies have compared mowing and grazing. We investigated the effect of mowing andgrazing on grassland vegetation using data from 11 long-term field trials situated in southern Sweden. We calculated thechange in the odds of finding species belonging to three different groups of indicators at the start of the treatment and after8 and 14 years. The used indicator groups were indicators of good management, excess nitrogen and poor management.The results revealed an increase in the odds of finding indicators of good management in mowed plots and an increasein finding indicators of excess nitrogen in grazed plots. The odds of finding indicators of poor management remainedunchanged. Results from sub-analysis of the grazing intensity showed a more negative effect from grazing with low grazingintensity than normal/high grazing intensity. Therefore, mowing is the best long-term management method for seminaturalgrasslands in Sweden and grazing using a low grazing intensity should be avoided.

  • 4814.
    Tälle, Malin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Wissman, Jörgen
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Gräsröjaren: ett skötselalternativ i artrika gräsmarker.2015In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 108, 254-259 p.Article in journal (Refereed)
  • 4815.
    Udd, Robert
    et al.
    Sectra AB, Linköping, Sweden.
    Asplund, Mikael
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Nadjm-Tehrani, Simin
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Kazemtabrizi, Mehrdad
    The Royal Institute of Technology, Stockholm, Sweden.
    Ekstedt, Mathias
    The Royal Institute of Technology, Stockholm, Sweden.
    Exploiting Bro for Intrusion Detection in a SCADA System2016In: Proceedings of the 2nd ACM International Workshop on Cyber-Physical System Security, ACM Digital Library, 2016, 44-51 p.Conference paper (Refereed)
    Abstract [en]

    Supervisory control and data acquisition (SCADA) systemsthat run our critical infrastructure are increasingly run withInternet-based protocols and devices for remote monitoring.The embedded nature of the components involved, and thelegacy aspects makes adding new security mechanisms in anefficient manner far from trivial. In this paper we studyan anomaly detection based approach that enables detect-ing zero-day malicious threats and benign malconfigurationsand mishaps. The approach builds on an existing platform(Bro) that lends itself to modular addition of new proto-col parsers and event handling mechanisms. As an examplewe have shown an application of the technique to the IEC-60870-5-104 protocol and tested the anomaly detector withmixed results. The detection accuracy and false positiverate, as well as real-time response was adequate for 3 ofour 4 created attacks. We also discovered some additionalwork that needs to be done to an existing protocol parser toextend its reach.

  • 4816.
    Uebel, Karl
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, Faculty of Science & Engineering.
    Conceptual Design of Complex Hydromechanical Transmissions2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis explores the conceptual design process of complex hydromechanical transmissions for mobile working machines. Efficient methods for design optimisation and controller development are presented to support the final concept selection.

    In the endeavour to develop new fuel-efficient driveline solutions for construction machines and off-road equipment new complex hydromechanical transmission concepts are being investigated. This pursuit is driven by stricter emission legislation, high fuel prices and a desire for a greener image both for customers and manufacturers. The trend towards more complex transmission architectures increases the need for more sophisticated product development methods. Complex multiple-mode transmissions are difficult to design and prototype and can be realised in a great number of architectures. By introducing a secondary energy storage in the machine the design space expands further for both hardware and software. There is accordingly a need for more reliable concept assessment in early design stages and the possibility to support concurrent engineering throughout the development process.

    Previous research on the design and development of hydromechanical transmissions has been limited to analysis of fixed concept designs or design optimization using very simple performance indicators. Existing methodologies for electrified on-road vehicles are not suitable for off-road working machines with hydromechanical transmissions and hydraulic energy storage.

    The proposed conceptual design process uses detailed quasi-static simulation models and targets to optimise the fuel efficiency of the specific machine specifications and operations. It is also shown how high-speed dynamic simulations can be used for controller development and hardware-in-the-loop simulations to support an efficient product design process. The methods are demonstrated for typical use cases targeting new transmission development for construction machines. Software control development is also treated using control optimisation and real-time simulation. Finally a novel hybrid hydromechanical motion system is presented for which an efficient design process is crucial to its end performance.

  • 4817.
    Ugo Abara, Precious
    et al.
    Department of Information Engineering, University of Padova, Italy.
    Ticozzi, Francesco
    Department of Information Engineering, University of Padova, Italy.
    Altafini, Claudio
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    An infinitesimal characterization of nonlinear contracting interference functions2016In: 2016 IEEE 55th Conference on Decision and Control (CDC), IEEE Press, 2016, 5257-5262 p.Conference paper (Refereed)
    Abstract [en]

    Contractive interference functions are a subclass of the standard interference functions used in the design and analysis of distributed power control algorithms for wireless networks. Their peculiarity is that for the resulting positive system the existence and global asymptotic stability of a unique positive equilibrium point is guaranteed. In this paper we give an infinitesimal characterization of nonlinear contractiveinterference functions in terms of the spectral radius of the Jacobian linearization at any point in the positive orthant. The condition we obtain, that the spectral radius is always less than 1, extends to the nonlinear case an equivalent property of linear interference functions, and leads to a Jacobian characterization similar to the one commonly used in contraction analysis of nonlinear systems.

  • 4818.
    Ukhov, Ivan
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    System-Level Analysis and Design under Uncertainty2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    One major problem for the designer of electronic systems is the presence of uncertainty, which is due to phenomena such as process and workload variation. Very often, uncertainty is inherent and inevitable. If ignored, it can lead to degradation of the quality of service in the best case and to severe faults or burnt silicon in the worst case. Thus, it is crucial to analyze uncertainty and to mitigate its damaging consequences by designing electronic systems in such a way that uncertainty is effectively and efficiently taken into account.

    We begin by considering techniques for deterministic system-level analysis and design of certain aspects of electronic systems. These techniques do not take uncertainty into account, but they serve as a solid foundation for those that do. Our attention revolves primarily around power and temperature, as they are of central importance for attaining robustness and energy efficiency. We develop a novel approach to dynamic steady-state temperature analysis of electronic systems and apply it in the context of reliability optimization.

    We then proceed to develop techniques that address uncertainty. The first technique is designed to quantify the variability in process parameters, which is induced by process variation, across silicon wafers based on indirect and potentially incomplete and noisy measurements. The second technique is designed to study diverse system-level characteristics with respect to the variability originating from process variation. In particular, it allows for analyzing transient temperature profiles as well as dynamic steady-state temperature profiles of electronic systems. This is illustrated by considering a problem of design-space exploration with probabilistic constraints related to reliability. The third technique that we develop is designed to efficiently tackle the case of sources of uncertainty that are less regular than process variation, such as workload variation. This technique is exemplified by analyzing the effect that workload units with uncertain processing times have on the timing-, power-, and temperature-related characteristics of the system under consideration.

    We also address the issue of runtime management of electronic systems that are subject to uncertainty. In this context, we perform an early investigation into the utility of advanced prediction techniques for the purpose of fine-grained long-range forecasting of resource usage in large computer systems.

    All the proposed techniques are assessed by extensive experimental evaluations, which demonstrate the superior performance of our approaches to analysis and design of electronic systems compared to existing techniques.

  • 4819.
    Ukhov, Ivan
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Eles, Petru Ion
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Peng, Zebo
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Probabilistic Analysis of Electronic Systems via Adaptive Hierarchical Interpolation2017In: IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, ISSN 0278-0070, E-ISSN 1937-4151, Vol. 36, no 11, 1883-1896 p.Article in journal (Refereed)
    Abstract [en]

    We present a framework for system-level analysis of electronic systems whose runtime behaviors depend on uncertain parameters. The proposed approach thrives on hierarchical interpolation guided by an advanced adaptation strategy, which makes the framework general and suitable for studying various metrics that are of interest to the designer. Examples of such metrics include the end-to-end delay, total energy consumption, and maximum temperature of the system under consideration. The framework delivers a light generative representation that allows for a straightforward, computationally efficient calculation of the probability distribution and accompanying statistics of the metric at hand. Our technique is illustrated by considering a number of uncertainty-quantification problems and comparing the corresponding results with exhaustive simulations.

  • 4820.
    Ukhov, Ivan
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Marculescu, Diana
    Department of Electrical and Computer Engineering, Carnegie Mellon University, USA.
    Eles, Petru Ion
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Peng, Zebo
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Fast Synthesis of Power and Temperature Profiles for the Development of Data-Driven Resource Managers2017Report (Other academic)
    Abstract [en]

    The goal of this work is to facilitate the development of proactive power- and temperature-aware resource managers that leverage machine learning in order to attain their objectives. In this context, the availability of sufficiently large amounts of relevant data, which are essential for learning and, therefore, exploration of research ideas, is elusive. In order to fulfill the need, we present a toolchain for fast generation of realistic power and temperature profiles of computer systems. The toolchain provides profuse representative data to learn from during development stages. The overreaching objective is to help research by making it tractable to experiment with the highly promising but data-demanding state-of-the-art techniques for prediction.

  • 4821.
    Ukhov, Ivan
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Marculescu, Diana
    Department of Electrical and Computer Engineering, Carnegie Mellon University, USA.
    Eles, Petru Ion
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Peng, Zebo
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Fine-Grained Long-Range Prediction of Resource Usage in Computer Clusters2017Report (Other academic)
    Abstract [en]

    In order to facilitate the development of intelligent resource managers of computer clusters, we investigate the utility of the state-of-the-art neural networks for the purpose of fine-grained long-range prediction of the resource usage in one such cluster. We consider a large data set of real-life traces and describe in detail our workflow, starting from making the data accessible for learning and finishing by predicting the resource usage of individual tasks multiple steps ahead. The experimental results indicate that such fine-grained traces as the ones considered possess a certain structure, and that this structure can be extracted by advanced machine-learning techniques and subsequently utilized for making informed predictions.

  • 4822.
    Ul Haque, Muhammad Fahim
    et al.
    Linköping University, Department of Electrical Engineering, Computer Engineering. Linköping University, Faculty of Science & Engineering.
    Johansson, Ted
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Liu, Dake
    Linköping University, Department of Electrical Engineering, Computer Engineering. Linköping University, Faculty of Science & Engineering.
    Large dynamic range PWM transmitter2016Conference paper (Other (popular science, discussion, etc.))
  • 4823.
    Ul Haque, Muhammad Fahim
    et al.
    Linköping University, Department of Electrical Engineering, Computer Engineering. Linköping University, Faculty of Science & Engineering.
    Johansson, Ted
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Liu, Dake
    Linköping University, Department of Electrical Engineering, Computer Engineering. Linköping University, Faculty of Science & Engineering.
    Power Efficienct Band-limited Pulse Width Modulated Transmitter2015Conference paper (Other (popular science, discussion, etc.))
  • 4824.
    ul Hasan, Kamran
    et al.
    Linköping University, Department of Science and Technology. Linköping University, Faculty of Science & Engineering. CESAT, Islamabad, Pakistan.
    Asif, Muhammad
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology. COMSATS Institute Informat Technology, Lahore, Pakistan.
    Umair Hassan, Muhammad
    COMSATS Institute Informat Technology, Lahore, Pakistan.
    Sandberg, Mats O.
    Acreo AB, Norrköping, Sweden.
    Nour, Omer
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Fagerholm, Siri
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Strålfors, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    A Miniature Graphene-based Biosensor for Intracellular Glucose Measurements2015In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 174, 574-580 p.Article in journal (Refereed)
    Abstract [en]

    We report on a small and simple graphene-based potentiometric sensor for the measurement of intracellular glucose concentration. A fine borosilicate glass capillary coated with graphene and subsequently immobilized with glucose oxidase (GOD) enzyme is inserted into the intracellular environment of a single human cell. The functional groups on the edge plane of graphene assist the attachment with the free amine terminals of GOD enzyme, resulting in a better immobilization. The sensor exhibits a glucose-dependent electrochemical potential against an Ag/AgCl reference microelectrode which is linear across the whole concentration range of interest (10 - 1000 mu M). Glucose concentration in human fat cell measured by our graphene-based sensor is in good agreement with nuclear magnetic resonance (NMR) spectroscopy.

  • 4825.
    ul Hassan Alvi, Naveed
    et al.
    University of Politecn Madrid, Spain.
    Eduardo David Soto Rodriguez, Paul
    University of Politecn Madrid, Spain.
    Aseev, Pavel
    University of Politecn Madrid, Spain.
    Jesus Gomez, Victor
    University of Politecn Madrid, Spain.
    ul Hassan Alvi, Ameed
    University of Agriculture Faisalabad, Pakistan.
    ul Hassan, Waheed
    Bahauddin Zakariya University, Pakistan.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Noetzel, Richard
    University of Milano Bicocca, Italy; University of Milano Bicocca, Italy.
    InN/InGaN quantum dot photoelectrode: Efficient hydrogen generation by water splitting at zero voltage2015In: NANO ENERGY, ISSN 2211-2855, Vol. 13, 291-297 p.Article in journal (Refereed)
    Abstract [en]

    Light to hydrogen conversion via water splitting is of immense interest as a clean, storable, and InN; renewable energy source (Tachibana et al., 2012 [1]; Maeda and Domen, 2010 [2]; van de Krol et al., Quantum dots; 2008 [3]; van Dorp et al., 2009 [4]; Kudo and Miseki, 2009 [5]) but efficient materials need to be found. Photoelect rode; To solve, InGaN has properties ideally suited and we demonstrate here that epitaxial InN quantum dots Water splitting; Hydrogen generation (QDs) more than double the photoelectrochemical (PEC) water splitting efficiency of an In0.54Ga046N photoelectrode. The InN/In0.54Ga0.46N-QDs-photoelectrode reveals a maximum incident-photon-tocurrent-conversion efficiency (IPCE) of up to 56% at a wavelength of 600 nm with hydrogen generation rate of 133 mot h(-1) cm(-2) at zero voltage under illumination of a 1000W Xenon arc lamp. The bare In0.51Ga0.16N-layer-photoelectrode reveals a much lower IPCE of 24% with hydrogen generation rate of 59 pmol h(-1) cm(-2). (C) 2015 Elsevier Ltd. All rights reserved.

  • 4826.
    Ullah Khan, Zia
    et al.
    Linköping University, Department of Science and Technology. Linköping University, Faculty of Science & Engineering. Norrköping, Sweden .
    Bubnova, Olga
    Linköping University, Department of Science and Technology. Linköping University, Faculty of Science & Engineering. Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, UK.
    Jafari, Mohammad Javad
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering.
    Brooke, Robert
    Linköping University, Department of Science and Technology. Linköping University, Faculty of Science & Engineering. University of South Australia, Mawson Institute, Mawson Lakes 5095, Australia.
    Liu, Xianjie
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Gabrielsson, Roger
    Linköping University, Department of Science and Technology. Linköping University, Faculty of Science & Engineering.
    Ederth, Thomas
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering.
    Evans, Drew R.
    University of South Australia, Mawson Institute, Australia.
    Andreasen, Jens W.
    Technical University of Denmark, Department of Energy Conversion and Storage, Roskilde, Denmark.
    Fahlman, Mats
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Crispin, Xavier
    Linköping University, Department of Science and Technology. Linköping University, Faculty of Science & Engineering.
    Acido-basic control of the thermoelectric properties of poly(3,4-ethylenedioxythiophene)tosylate (PEDOT-Tos) thin films2015In: Journal of Materials Chemistry C, ISSN 2050-7526, E-ISSN 2050-7534, Vol. 3, 10616-10623 p.Article in journal (Refereed)
    Abstract [en]

    PEDOT-Tos is one of the conducting polymers that displays the most promising thermoelectric properties. Until now, it has been utterly difficult to control all the synthesis parameters and the morphology governing the thermoelectric properties. To improve our understanding of this material, we study the variation in the thermoelectric properties by a simple acido-basic treatment. The emphasis of this study is to elucidate the chemical changes induced by acid (HCl) or base (NaOH) treatment in PEDOT-Tos thin films using various spectroscopic and structural techniques. We could identify changes in the nanoscale morphology due to anion exchange between tosylate and Cl- or OH-. But, we identified that changing the pH leads to a tuning of the oxidation level of the polymer, which can explain the changes in thermoelectric properties. Hence, a simple acid-base treatment allows finding the optimum for the power factor in PEDOT-Tos thin films.

  • 4827.
    Ullah Khan, Zia
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Edberg, Jesper
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Max Hamedi, Mahiar
    KTH Royal Institute Technology, Sweden.
    Gabrielsson, Roger
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Granberg, Hjalmar
    Innventia AB, Sweden.
    Wågberg, Lars
    KTH Royal Institute Technology, Sweden.
    Engquist, Isak
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Crispin, Xavier
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Thermoelectric Polymers and their Elastic Aerogels2016In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 28, no 22, 4556-4562 p.Article in journal (Refereed)
    Abstract [en]

    Electronically conducting polymers constitute an emerging class of materials for novel electronics, such as printed electronics and flexible electronics. Their properties have been further diversified to introduce elasticity, which has opened new possibility for "stretchable" electronics. Recent discoveries demonstrate that conducting polymers have thermoelectric properties with a low thermal conductivity, as well as tunable Seebeck coefficients - which is achieved by modulating their electrical conductivity via simple redox reactions. Using these thermoelectric properties, all-organic flexible thermoelectric devices, such as temperature sensors, heat flux sensors, and thermoelectric generators, are being developed. In this article we discuss the combination of the two emerging fields: stretchable electronics and polymer thermoelectrics. The combination of elastic and thermoelectric properties seems to be unique for conducting polymers, and difficult to achieve with inorganic thermoelectric materials. We introduce the basic concepts, and state of the art knowledge, about the thermoelectric properties of conducting polymers, and illustrate the use of elastic thermoelectric conducting polymer aerogels that could be employed as temperature and pressure sensors in an electronic-skin.

  • 4828.
    Ullah, Zia
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Thermoelectric Devices with Electronic and Ionic Conducting Polymers2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The energy consumption in the world is continuously growing and the sources of energy are largely dominated by fossil fuels. However, the resources of oil, gas and coal are diminishing in capacity. Moreover the CO2 emissions arising from their combustion is a great concern because it induces climate changes that threaten our habitat. There is a dire need to look for alternative sources of energies and to minimize losses of energy in our surroundings. Heat engines and turbines typically running with fossil energy have efficiencies of about 35%, i.e. 65% of the energy is lost in the form of heat. Low temperature heat (<200 C) is almost always wasted in power plants, industries, automobiles and household appliances. This is a huge resource that can be directly converted to electricity through the concept of thermoelectricity. Major challenges for heat to electricity conversion include finding the abundant materials with efficient thermoelectric (TE) conversion that can be mass produced at low cost.

    This thesis presents an investigation of the TE properties of electronic and ionic conducting polymers, as well as their implementation in thermoelectric devices. This is a journey from thin solid films on a substrate to wet and liquid media and towards bulk structures utilizing the same core concept of thermoelectricity. The TE device concepts introduced here are suitable for various heat sources i.e. continuous, intermittent and instantaneous. The thesis has three major parts as follows:

    Conducting polymers (CPs) have been studied mainly as thin films. They have been synthesized in different ways and their properties have been compared to propose the most efficient amongst them for thermoelectricity. Simple methods of exposure to certain gases or liquids have been used to tune their TE properties and demonstrated its applications in thermoelectric generator (TEGs).

    Ionic materials have also been studied as potential candidates for thermoelectricity. Polyelectrolytes constitute a special class of electrolytes with dissimilar sizes of ions; a polymeric ion and a small counter ion. The movement of the small sodium (Na+) cation under heat gradient was explored in wet films and in solution. Because the ions could not cross the electrolyte-electrode junction, we propose the idea of ionic thermoelectric supercapacitor (ITESC), suitable for intermittent heat source.

    Nanofibrillated cellulose (NFC) has been used along with conducting polymers to realize the three dimensional conducting bulks as a TEG leg. NFC bulks were coated with conducting polymers as a first approach and later the mixture of (NFC & CP) was freeze-dried. The later approach resulted in mechanically flexible structures that were used as dual sensors for pressure and temperature based on the TE properties of the CP which can be utilized for electronic skin applications.

    The thesis shows new ways of utilizing waste heat using polymeric materials and points to a sensory application area, broadening the horizons of thermoelectricity.

  • 4829.
    Ullsten, Sara
    et al.
    Uppsala University, Sweden.
    Bohman, Sara
    Uppsala University, Sweden.
    Oskarsson, Marie E.
    Uppsala University, Sweden.
    Nilsson, Peter
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Westermark, Gunilla T.
    Uppsala University, Sweden.
    Carlsson, Per-Ola
    Uppsala University, Sweden.
    Islet amyloid deposits preferentially in the highly functional and most blood-perfused islets2017In: Endocrine Connections, ISSN 2049-3614, E-ISSN 2049-3614, Vol. 6, no 7, 458-468 p.Article in journal (Refereed)
    Abstract [en]

    Islet amyloid and beta cell death in type 2 diabetes are heterogeneous events, where some islets are affected early in the disease process, whereas others remain visibly unaffected. This study investigated the possibility that inter-islet functional and vascular differences may explain the propensity for amyloid accumulation in certain islets. Highly blood-perfused islets were identified by microspheres in human islet amyloid polypeptide expressing mice fed a high-fat diet for three or 10 months. These highly blood-perfused islets had better glucose-stimulated insulin secretion capacity than other islets and developed more amyloid deposits after 10 months of high-fat diet. Similarly, human islets with a superior release capacity formed more amyloid in high glucose culture than islets with a lower release capacity. The amyloid formation in mouse islets was associated with a higher amount of prohormone convertase 1/3 and with a decreased expression of its inhibitor proSAAS when compared to islets with less amyloid. In contrast, levels of prohormone convertase 2 and expression of its inhibitor neuroendocrine protein 7B2 were unaltered. A misbalance in prohormone convertase levels may interrupt the normal processing of islet amyloid polypeptide and induce amyloid formation. Preferential amyloid load in the most blood-perfused and functional islets may accelerate the progression of type 2 diabetes.

  • 4830.
    Umair, Shakila
    et al.
    Division of Environmental Strategies Research - Fms, Royal Institute of Technology KTH, Stockholm, Sweden; Centre for Sustainable Communications (CESC), Royal Institute of Technology KTH, Stockholm, Sweden.
    Anderberg, Stefan
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Potting, José
    Division of Environmental Strategies Research - Fms, Royal Institute of Technology KTH, Stockholm, Sweden.
    Informal electronic waste recycling in Pakistan2016In: The Journal of Solid Waste Technology and Management, ISSN 1088-1697, Vol. 42, no 3, 222-235 p.Article in journal (Refereed)
    Abstract [en]

    The use of Information and Communication Technologies (ICTs) is growing dramatically all over the world. The fast growth and diffusion of ICTs, their early obsolescence and short life have made electronic waste (e-waste) to the fastest growing waste stream in the world. This waste stream is valuable and highly toxic at the same time, and therefore it requires proper handling. Most e-waste currently ends up in developing countries, like Pakistan, where it is usually recycled informally. Informal recycling involves crude processes, which harm the environment and have severe impacts on the health of recycling workers. This paper analyses the e-waste flows and the informal recycling system in Pakistan, and related governance challenges. Based on field studies in three major cities in Pakistan, we investigate why the e-waste flows keep entering the country, the routes through which they end up in the informal recycling, the actual recycling processes, and identify the various stakeholders and their roles. The analysis illustrates the poor governance that results from weak enforcement of legislation, the complexities emerging with numerous stakeholders, the profitability of informal recycling, little concern for the health damaging exposure for workers from poorest and most vulnerable people in society, and the lack of awareness of the hazards involved. The paper highlights how this business is a market driven entity without priority for proper e-waste handling, which is also hampered by lacking characteristics of good governance, which make it a challenge to control this business.

  • 4831.
    Umans, Timurs
    et al.
    Högskolan Kristianstad.
    Broberg, Pernilla
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Science & Engineering. Högskolan Kristianstad.
    Fjelkner, Annika
    Högskolan Kristianstad.
    Smith, Elin
    Högskolan Kristianstad.
    Diversity and learning outcomes in student dyads during work integrated learning projects2015Conference paper (Other academic)
  • 4832.
    Umans, Timurs
    et al.
    Högskolan Kristianstad.
    Broberg, Pernilla
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Science & Engineering. Högskolan Kristianstad.
    Schmidt, Manuela
    Högskolan Kristianstad.
    Nilsson, Sofie
    Högskolan Kristianstad.
    Olsson, Emma
    Högskolan Kristianstad.
    Feeling well by being together: Study of Swedish auditors2015Conference paper (Refereed)
  • 4833.
    Umans, Timurs
    et al.
    Kristianstad University, Kristianstad, Sweden, Linnaeus University, Växjö, Sweden.
    Broberg, Pernilla
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Science & Engineering. Kristianstad University, Kristianstad, Sweden.
    Schmidt, Manuela
    Kristianstad University, Kristianstad, Sweden,.
    Nilsson, Sofie
    Kristianstad University, Kristianstad, Sweden,.
    Olsson, Emma
    Kristianstad University, Kristianstad, Sweden,.
    Feeling well by being together: Study of swedish auditors.2016In: Work: A journal of Prevention, Assesment and rehabilitation, ISSN 1051-9815, E-ISSN 1875-9270, Vol. 54, no 1, 79-86 p.Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: As guardians of the public interest, auditors represent a unique occupational group. The group that has shown to experience high level of stress and overload often being associated with environmentally imposed responsibility as well as organizationally imposed performance demands. It is the later aspects, represented by the concept of organizational culture, that is being highlighted in this papers and its relationship to auditors well-beingOBJECTIVES:The paper aims to explore organizational culture as an antecedent of auditors' well-being, which is assumed to have important consequences for the quality of auditors' work.

    METHODS: This study is based on a survey of 207 Swedish auditors. Using established and validated instruments measuring aspects of organizational culture and personal well-being, the study employed correlations and multiple regression analysis in testing the relationship between the two.

    RESULTS: The results of the study suggest that increasing the degree of collectivistic organizational culture has a positive relationship with three aspects of well-being: Job satisfaction, life balance and life satisfaction.

    CONCLUSIONS: This study is the first attempt to explore well-being of auditors and its antecedents represented by organizational culture. Contrary to the expectation that auditors take an individualistic approach to their work, this study establishes that auditors feel best in a work environment characterized by a collectivist organizational culture.

  • 4834.
    Umans, Timurs
    et al.
    Högskolan Kristianstad.
    Collin, Sven-Olof
    Linnéuniversitetet.
    Broberg, Pernilla
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Science & Engineering. Högskolan Kristianstad.
    Nilsson, Sofie
    Högskolan Kristianstad.
    Olsson, Emma
    Högskolan Kristianstad.
    Organization Culture and Well-Being of Swedish Auditors2015Conference paper (Refereed)
  • 4835.
    Unger, Jonas
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Banterle, Francesco
    Visual Computing Laboratory at ISTI-CNR, Italy.
    Mantiuk, Rafal
    Computer Laboratory, University of Cambridge, UK.
    Eilertsen, Gabriel
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    The HDR-video pipeline: From capture and image reconstruction to compression and tone mapping2016Conference paper (Other academic)
    Abstract [en]

    High dynamic range (HDR) video technology has gone through remarkable developments over the last few years;HDR-video cameras are being commercialized, new algorithms for color grading and tone mapping specifically designed for HDR-video have recently been proposed, and the first open source compression algorithms for HDR-video are becoming available. HDR-video represents a paradigm shift in imaging and computer graphics, which has and will continue to generate a range of both new research challenges and applications. This intermediate-level tutorial will give an in-depth overview of the full HDR-video pipeline present several examples of state-of-the-art algorithms and technology in HDR-video capture, tone mapping, compression and specific applications in computer graphics.

  • 4836.
    Unger, Jonas
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Hajisharif, Saghi
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Kronander, Joel
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Unified reconstruction of RAW HDR video data2016In: High dynamic range video: from acquisition to display and applications / [ed] Frédéric Dufaux, Patrick Le Callet, Rafal K. Mantiuk, Marta Mrak, London, United Kingdom: Academic Press, 2016, 1st, 63-82 p.Chapter in book (Other academic)
    Abstract [en]

    Traditional HDR capture has mostly relied on merging images captured with different exposure times. While this works well for static scenes, dynamic scenes poses difficult challenges as registration of differently exposed images often leads to ghosting and other artifacts. This chapter reviews methods which capture HDR-video frames within a single exposure time, using either multiple synchronised sensors, or by multiplexing of the sensor response spatially across the sensor. Most previous HDR reconstruction methods perform demoisaicing, noise reduction, resampling (registration), and HDR-fusion in separate steps. This chapter presents a framework for unified HDR-reconstruction, including all steps in the traditional imaging pipeline in a single adaptive filtering operation, and describes an image formation model and a sensor noise model applicable to both single-, and multi-sensor systems. The benefits of using raw data directly are demonstrated with examples using input data from multiple synchronized sensors, and single images with varying per-pixel gain.

  • 4837.
    Unnikrishnan, Vishnu
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Design of VCO-based ADCs2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Today's complex electronic systems with billions of transistors on a single die are enabled by the aggressive scaling down of the device feature size at an exponential rate as predicted by the Moore's law. Digital circuits benefit from technology scaling to become faster, more energy efficient as well as more area efficient as the feature size is scaled down. Moreover, digital design also benefits from mature CAD tools that simplify the design and cross-technology porting of complex systems, leveraging on a cell-based design methodology. On the other hand, the design of analog circuits is getting increasingly difficult as the feature size scales down into the deep nanometer regime due to a variety of reasons like shrinking voltage headroom, reducing intrinsic gain of the devices, increasing noise coupling between circuit nodes due to shorter distances etc. Furthermore, analog circuits are still largely designed with a full custom design ow that makes their design and porting tedious, slow, and expensive. In this context, it is attractive to consider realizing analog/mixed-signal circuits using standard digital components. This leads to scaling-friendly mixed-signal blocks that can be designed and ported using the existing CAD framework available for digital design. The concept is already being applied to mixed-signal components like frequency synthesizers where all-digital architectures are synthesized using standard cells as basic components. This can be extended to other mixed-signal blocks like digital-to-analog and analog to- digital converters as well, where the latter is of particular interest in this thesis.

    A voltage-controlled oscillator (VCO)-based analog-to-digital converter (ADC) is an attractive architecture to achieve all-digital analog-to digital conversion due to favorable properties like shaping of the quantization error, inherent anti-alias filtering etc. Here a VCO operates as a signal integrator as well as a quantizer. A converter employing a ring oscillator as the VCO lends itself to an all-digital implementation.

    In this dissertation, we explore the design of VCO-based ADCs synthesized using digital standard cells with the long-term goal of achieving high performance data converters built from low accuracy switch components. In a first step, an ADC is designed using vendor supplied standard cells and fabricated in a 65 nm CMOS process. The converter delivers an 8-bit ENOB over a 25 MHz bandwidth while consuming 3.3 mW of power resulting in an energy efficiency of 235 fJ/step (Walden FoM). Then we utilize standard digital CAD tools to synthesize converter designs that are fully described using a hardware description language. A polynomial-based digital post-processing scheme is proposed to correct for the VCO nonlinearity. In addition, pulse modulation schemes like delta modulation and asynchronous sigma-delta modulation are used as a signal pre-coding scheme, in an attempt to reduce the impact of VCO nonlinearity on converter performance. In order to investigate the scaling benefits of all-digital data conversion, a VCO-based converter is designed in a 28 nm CMOS process. The design delivers a 13.4-bit ENOB over a 5 MHz bandwidth achieving an energy efficiency of 4.3 fJ/step according to post-synthesis schematic simulation, indicating that such converters have the potential of achieving good performance in deeply scaled processes by exploiting scaling benefits. Furthermore, large conversion errors caused by non-ideal sampling of the oscillator phase are studied. An encoding scheme employing ones counters is proposed to code the sampled ring oscillator output into a number, which is resilient to a class of sampling induced errors modeled by temporal reordering of the transitions in the ring. The proposed encoding reduces the largest error caused by random reordering of up to six subsequent bits in the sampled signal from 31 to 2 LSBs. Finally, the impact of process, voltage, and temperature (PVT) variations on the performance while operating the converter from a subthreshold supply is investigated. PVT-adaptive solutions are suggested as a means to achieve energy-efficient operation over a wide range of PVT conditions.

  • 4838.
    Unnikrishnan, Vishnu
    et al.
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Rao Pathapati, Srinivasa
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Vesterbacka, Mark
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    A Fully Synthesized All-Digital VCO-Based Analog-to-Digital Converter2015In: 2015 NORDIC CIRCUITS AND SYSTEMS CONFERENCE (NORCAS) - NORCHIP and INTERNATIONAL SYMPOSIUM ON SYSTEM-ON-CHIP (SOC), Institute of Electrical and Electronics Engineers (IEEE), 2015Conference paper (Refereed)
    Abstract [en]

    Synthesis of all-digital ADCs leads to significant reduction in design cost and design time, besides improving cross-technology portability. In this work, an ADC which is fully described in digital HDL is synthesized, placed and routed using standard digital design tools. A VCO-based architecture is chosen for its synthesizability. The design flow employed is discussed. The circuit is synthesized using the standard cell library in a 65 nm CMOS process, delivering a resolution of 9 ENOB over 10 MHz bandwidth according to post layout parasitic extracted simulations using the Spectre simulator. Post synthesis and post place-and-route performances are provided.

  • 4839.
    Unnikrishnan, Vishnu
    et al.
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Vesterbacka, Mark
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    A NAND Gate Based Standard Cell VCO for Use in Synthesizable ADCs2015In: 2015 NORDIC CIRCUITS AND SYSTEMS CONFERENCE (NORCAS) - NORCHIP and INTERNATIONAL SYMPOSIUM ON SYSTEM-ON-CHIP (SOC), IEEE , 2015Conference paper (Refereed)
    Abstract [en]

    Synthesizable all-digital ADCs lead to reduced design cost and design time as well as to low cross-technology porting costs. VCO-based ADC is an attractive candidate for the synthesis of ADCs using standard cells. However, a VCO, which is controlled by an analog input signal, is difficult to implement using standard digital circuits. Supply controlled ring oscillators using static CMOS inverters are used in prior works. In this work, an alternative VCO built using NAND gates is proposed for use in synthesizable converters. The circuit is demonstrated by employing it in an ADC synthesized from an HDL description. Transistor level simulation of the resulting netlist using the Spectre simulator shows that a performance of 10 bit ENOB over a 10 MHz bandwidth can be achieved after digital correction, using the proposed VCO.

  • 4840.
    Unnikrishnan, Vishnu
    et al.
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Vesterbacka, Mark
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Design of a VCO-based ADC in 28 nm CMOS2016In: 2016 2ND IEEE NORDIC CIRCUITS AND SYSTEMS CONFERENCE (NORCAS), IEEE , 2016Conference paper (Refereed)
    Abstract [en]

    A VCO-based ADC is designed and synthesized in a 28 nm FDSOI CMOS process to investigate the scaling benefits of all-digital analog-to-digital conversion. A coarse-fine quantizer is used to obtain high energy efficiency. Common patterns of sample errors at the multi-phase VCO output are identified and mitigated. Final design indicates an ENOB of 13.4 and a Walden FoM of 4.3 fJ/step over a 5 MHz bandwidth while sampling at 150 MHz, according to schematic simulation of the synthesized netlist.

  • 4841.
    Unnikrishnan, Vishnu
    et al.
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Vesterbacka, Mark
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Linearization of Synthesizable VCO-Based ADCs Using Delta Modulation2015In: 2015 European Conference on Circuit Theory and Design (ECCTD), Institute of Electrical and Electronics Engineers (IEEE), 2015, 280-283 p.Conference paper (Refereed)
    Abstract [en]

    VCO-based ADC is an attractive candidate for the synthesis of all-digital ADCs using standard cells. However, the non-linearity of a synthesizable VCO requires digital post-processing to obtain good performance. We propose another solution where the input analog signal is pre-coded into a delta-modulated pulse stream which is used to drive a VCO-based converter. This causes the oscillator to operate at two distinct frequencies thereby eliminating the VCO non-linearity from the converter transfer function. A circuit is proposed that consists of a synthesized digital block realizing all the active parts of the circuit and a passive RC net used as an integrator. Spectre simulation of the netlist synthesized using a 65 nm standard cell library shows a performance of 8.2 bit ENOB over a 3 MHz bandwidth without using any digital post-processing.

  • 4842.
    Unnikrishnan, Vishnu
    et al.
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Vesterbacka, Mark
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Linearization of VCO-based ADCs using asynchronous sigma-delta modulation2016In: 2016 IEEE 59TH INTERNATIONAL MIDWEST SYMPOSIUM ON CIRCUITS AND SYSTEMS (MWSCAS), New York: Institute of Electrical and Electronics Engineers , 2016, 842-845 p.Conference paper (Refereed)
    Abstract [en]

    Asynchronous sigma-delta modulation is investigated as an alternative linearization scheme for all-digital voltage controlled oscillator based analog-to-digital converters, which commonly require digital post processing to achieve good linearity. The modulator output, when used to drive a VCO-based converter, causes the oscillator to operate at two fixed frequencies thereby removing the VCO nonlinearity from the transfer function. A circuit is proposed consisting of a digital block and a passive RC circuit operating as an integrator. Spectre simulation of the design synthesized using a 65 nm standard cell library indicate that a harmonic suppression up to -60 dB is feasible.

  • 4843.
    Unnikrishnan, Vishnu
    et al.
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Vesterbacka, Mark
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Mitigation of Sampling Errors in VCO-Based ADCs2017In: IEEE Transactions on Circuits and Systems Part 1: Regular Papers, ISSN 1549-8328, E-ISSN 1558-0806, Vol. 64, no 7, 1730-1739 p.Article in journal (Refereed)
    Abstract [en]

    Voltage-controlled-oscillator-based analog-to-digital converter (ADC) is a scaling-friendly architecture to build ADCs in fine-feature complimentary metal-oxide-semiconductor processes. Lending itself to an implementation with digital components, such a converter enables design automation with existing digital CAD hence reducing design and porting costs compared with a custom design flow. However, robust architectures and circuit techniques that reduce the dependence of performance on component accuracy are required to achieve good performance while designing converters with low accuracy components like standard cells in deeply-scaled processes. This paper investigates errors resulting from the sampling of a fast switching multi-phase ring oscillator output. A scheme employing ones-counters is proposed to encode the sampled ring oscillator code into a binary representation, which is resilient to a class of sampling induced errors modeled by the temporal reordering of the transitions in the ring. In addition to correcting errors caused by deterministic reordering, proposed encoding suppresses conversion errors in the presence of arbitrary reordering patterns that may result from automatic place-and-route in wire-delay dominated processes. The error suppression capability of the encoding is demonstrated using MATLAB simulation. The proposed encoder reduces the error caused by the random reordering of six subsequent bits in the sampled signal from 31 to 2 LSBs for a 31-stage oscillator.

  • 4844.
    Unnikrishnan, Vishnu
    et al.
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Vesterbacka, Mark
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Mixed-Signal Design Using Digital CAD2016In: Proceedings IEEE Computer Society Annual Symposium on VLSI ISVLSI 2016, 2016, 6-11 p.Conference paper (Refereed)
    Abstract [en]

    The paper investigates the use of the existing CAD framework for digital circuit synthesis to design and synthesize a select set of mixed-signal functions like analog-to-digital and digital-to-analog conversions. This approach leads to fast and low cost design of technology portable system-on-chip solutions with analog interfaces. Some circuit examples for implementation of data conversion using digital circuits are discussed, leveraging on time-domain signal processing. Some of the signal corruption mechanisms in time-domain signal processing systems are considered in order to suggest adaptations to the existing digital design flow for the synthesis of mixed-signal circuits. As an example to show that high performance data conversion circuits can be realized using low accuracy general purpose components, an ADC is designed and synthesized with the vendor supplied standard cell library in a 65 nm CMOS process. Spectre simulation results show the feasibility of employing a digital CAD framework to synthesize high performance mixed-signal circuits, by applying time-domain signal processing.

  • 4845.
    Unnikrishnan, Vishnu
    et al.
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Vesterbacka, Mark
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Alvandpour, Atila
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    VCO-based ADCs for IoT applications2016In: 2016 International Symposium on Integrated Circuits (ISIC), IEEE Press, 2016, 1-4 p.Conference paper (Refereed)
    Abstract [en]

    Internet of things (IoT) benefits from fast and low cost development of technology portable re-configurable hardware. Low power consumption is desired for applications operating from harvested or limited energy. Subthreshold operation of VCO-based ADCs is investigated in this work in order to meet these challenges. A ring VCO built using NAND gates is used for reliable operation in the subthreshold region. The impact of supply scaling and PVT variations on the VCO characteristics as well as on the converter performance is studied using transistor level simulations. Some solutions are suggested towards energy efficient operation over a wide range of PVT conditions.

  • 4846.
    Urbanaviciute, Indre
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Complex Materials and Devices. Linköping University, Faculty of Science & Engineering.
    Meng, Xiao
    Eindhoven University of Technology, Netherlands.
    Cornelissen, Tim
    Linköping University, Department of Physics, Chemistry and Biology, Complex Materials and Devices. Linköping University, Faculty of Science & Engineering.
    Gorbunov, Andrey V.
    Eindhoven University of Technology, Netherlands.
    Bhattacharjee, Subham
    Eindhoven University of Technology, Netherlands.
    Sijbesma, Rint P.
    Eindhoven University of Technology, Netherlands.
    Kemerink, Martijn
    Linköping University, Department of Physics, Chemistry and Biology, Complex Materials and Devices. Linköping University, Faculty of Science & Engineering.
    Tuning the Ferroelectric Properties of Trialkylbenzene-1,3,5-tricarboxamide (BTA)2017In: ADVANCED ELECTRONIC MATERIALS, ISSN 2199-160X, Vol. 3, no 7, 1600530Article in journal (Refereed)
    Abstract [en]

    This study demonstrates how simple structural modification of a prototypical organic ferroelectric molecule can be used to tune its key ferroelectric properties. In particular, it is found that shortening the alkyl chain length of trialkylbenzene-1,3,5-tricarboxamide (BTA) from C18H37 to C6H13 causes an increase in depolarization activation energy (approximate to 1.1-1.55 eV), coercive field (approximate to 25-40 V mu m(-1)), and remnant polarization (approximate to 20-70 mC m(-2)). As the polarization enhancement far exceeds the geometrically expected factor, these observations are attributed to an increase in the intercolumnar interaction. The combination of the mentioned characteristics results in a record polarization retention time of close to three months at room temperature for capacitor devices of the material having the shortest alkyl chain. The long retention and the remnant polarization that is as high as that of P(VDF:TrFE) distinguish the BTA-C6 material from other small molecular organic ferroelectrics and make it a perspective choice for applications that require cheap, flexible, and lightweight ferroelectrics.

  • 4847.
    Uziela, Karolis
    et al.
    Stockholm University, Sweden.
    Menendez Hurtado, David
    Stockholm University, Sweden.
    Shu, Nanjiang
    Stockholm University, Sweden; Science Life Lab, Sweden.
    Wallner, Björn
    Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics. Linköping University, Faculty of Science & Engineering.
    Elofsson, Arne
    Stockholm University, Sweden.
    ProQ3D: improved model quality assessments using deep learning2017In: Bioinformatics, ISSN 1367-4803, E-ISSN 1367-4811, Vol. 33, no 10, 1578-1580 p.Article in journal (Refereed)
    Abstract [en]

    A Summary: Protein quality assessment is a long-standing problem in bioinformatics. For more than a decade we have developed state-of-art predictors by carefully selecting and optimising inputs to a machine learning method. The correlation has increased from 0.60 in ProQ to 0.81 in ProQ2 and 0.85 in ProQ3 mainly by adding a large set of carefully tuned descriptions of a protein. Here, we show that a substantial improvement can be obtained using exactly the same inputs as in ProQ2 or ProQ3 but replacing the support vector machine by a deep neural network. This improves the Pearson correlation to 0.90 (0.85 using ProQ2 input features). Supplementary information: Supplementary data are available at Bioinformatics online.

  • 4848.
    Uziela, Karolis
    et al.
    Stockholm University, Sweden.
    Shu, Nanjiang
    Stockholm University, Sweden; Science Life Lab, Sweden.
    Wallner, Björn
    Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics. Linköping University, Faculty of Science & Engineering.
    Elofsson, Arne
    Stockholm University, Sweden.
    ProQ3: Improved model quality assessments using Rosetta energy terms2016In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, 33509Article in journal (Refereed)
    Abstract [en]

    Quality assessment of protein models using no other information than the structure of the model itself has been shown to be useful for structure prediction. Here, we introduce two novel methods, ProQRosFA and ProQRosCen, inspired by the state-of-art method ProQ2, but using a completely different description of a protein model. ProQ2 uses contacts and other features calculated from a model, while the new predictors are based on Rosetta energies: ProQRosFA uses the full-atom energy function that takes into account all atoms, while ProQRosCen uses the coarse-grained centroid energy function. The two new predictors also include residue conservation and terms corresponding to the agreement of a model with predicted secondary structure and surface area, as in ProQ2. We show that the performance of these predictors is on par with ProQ2 and significantly better than all other model quality assessment programs. Furthermore, we show that combining the input features from all three predictors, the resulting predictor ProQ3 performs better than any of the individual methods. ProQ3, ProQRosFA and ProQRosCen are freely available both as a webserver and stand-alone programs at http://proq3.bioinfo.se/.

  • 4849.
    Uziela, Karolis
    et al.
    Stockholm University, Sweden.
    Wallner, Björn
    Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics. Linköping University, Faculty of Science & Engineering. Swedish e-science Research Centre (SeRC).
    ProQ2: estimation of model accuracy implemented in Rosetta2016In: Bioinformatics, ISSN 1367-4803, E-ISSN 1367-4811, Vol. 32, no 9, 1411-1413 p.Article in journal (Refereed)
    Abstract [en]

    Motivation: Model quality assessment programs are used to predict the quality of modeled protein structures. They can be divided into two groups depending on the information they are using: ensemble methods using consensus of many alternative models and methods only using a single model to do its prediction. The consensus methods excel in achieving high correlations between prediction and true quality measures. However, they frequently fail to pick out the best possible model, nor can they be used to generate and score new structures. Single-model methods on the other hand do not have these inherent shortcomings and can be used both to sample new structures and to improve existing consensus methods. Results: Here, we present an implementation of the ProQ2 program to estimate both local and global model accuracy as part of the Rosetta modeling suite. The current implementation does not only make it possible to run large batch runs locally, but it also opens up a whole new arena for conformational sampling using machine learned scoring functions and to incorporate model accuracy estimation in to various existing modeling schemes. ProQ2 participated in CASP11 and results from CASP11 are used to benchmark the current implementation. Based on results from CASP11 and CAMEO-QE, a continuous benchmark of quality estimation methods, it is clear that ProQ2 is the single-model method that performs best in both local and global model accuracy.

  • 4850.
    Uzun, Lokman
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering. Hacettepe University, Beytepe, Ankara, Turkey.
    Rezai, Babak
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering. Amirkabir University of Technology, Tehran Iran.
    Garipcan, Bora
    Boğaziçi University, Institute of Biomedical Engineering, Istanbul, Turkey.
    Turner, Anthony
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Reactive electrospun nanofibres as a versatile functional material on electrode surfaces for impedimetric sensor design2016In: Proceedings and Abstract Book : American Advanced Materials Congress 4-9 December 2016 / [ed] Ashutosh Tiwari, India: VBRI Press , 2016Conference paper (Other academic)
    Abstract [en]

    Electrospinning is a highly attractive technique to incorporate functional materials into nanofibre structures. In this process, the polymer structure is transformed from a bulk to a fibrous network by means of a high voltage applied between two-electrode systems.1 The functionality of the bulk polymers defines the functionality of the final nanofibres as well, which is a major limitation for producing ease-to-use electrospun nanofibres.2 For this reason, researchers have focused on reactive electrospinning to produce functional nanofibres with the desired properties. For this aim, an extra step, oligomerisation, is applied to elongate the polymeric chain just before the electrospinning step. In addition, it is possible to adjust the functionality of the final fibres by using an appropriate initial functional monomer.3 Herein, we focused our attention on developing reactive electrospun nanofibres for designing a versatile functional material on electrode surfaces. We have developed a reactive electrospinning process for a functional monomer, glycidyl methacrylate, to obtain epoxy-containing fibres that are ready for immobilisation of a recognition element directly on the surface. After that, Anti-albumin antibody molecules were immobilised on the surface as a recognition element. Then the electrodes were characterised by scanning electron microscopy and Fourier transform infrared spectroscopy. The factors affecting albumin recognition were also evaluated by varying the dipping time, pH, and concentration. The results indicated that anti-albumin antibody molecules were successfully immobilised on the fibres and play an efficient recognition role for albumin detection in aqueous solutions as well as in human serum. In conclusion, the material and method developed here shows promise for the development of versatile sensor platforms, due to its excellent performance, reproducibility and low cost.

949596979899100 4801 - 4850 of 5318
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf