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  • 14001.
    Pang, Xiaodan
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Schatz, Richard
    KTH Royal Institute of Technology, Sweden.
    Storck, Joakim
    KTH Royal Institute of Technology, Sweden.
    Udalcovs, Aleksejs
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Navarro, Jaime Rodrigo
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Kakkar, Aditya
    KTH Royal Institute of Technology, Sweden.
    Maisons, Gregory
    mirSense Centre d’intégration NanoInnov, France.
    Carras, Mathieu
    mirSense Centre d’intégration NanoInnov, France.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Popov, Sergei
    KTH Royal Institute of Technology, Sweden.
    Lourdudoss, Sebastian
    KTH Royal Institute of Technology, Sweden.
    Gigabit free-space multi-level signal transmission with a mid-infrared quantum cascade laser operating at room temperature2017In: Optics Letters, ISSN 0146-9592, E-ISSN 1539-4794, Vol. 42, no 18, p. 3646-3649Article in journal (Refereed)
    Abstract [en]

    Gigabit free-space transmissions are experimentally demonstrated with a quantum cascaded laser (QCL) emitting at mid-wavelength infrared of 4.65 μm, and a commercial infrared photovoltaic detector. The QCL operating at room temperature is directly modulated using on–off keying and, for the first time, to the best of our knowledge, four- and eight-level pulse amplitude modulations (PAM-4, PAM-8). By applying pre- and post-digital equalizations, we achieve up to 3 Gbit/s line data rate in all three modulation configurations with a bit error rate performance of below the 7% overhead hard decision forward error correction limit of 3.8 × 10−3. The proposed transmission link also shows a stable operational performance in the lab environment.

  • 14002.
    Pang, Xiaodan
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Technology, Sweden.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Zhang, Lu
    KTH Royal Institute of Technology, Sweden; Shanghai Jiao Tong University, China.
    Schatz, Richard
    KTH Royal Institute of Technology, Sweden.
    Udalcovs, Aleksejs
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Storck, Joakim
    KTH Royal Institute of Technology, Sweden.
    Maisons, Gregory
    mirSense, France.
    Carras, Mathieu
    mirSense, France.
    Xiao, Shilin
    Shanghai Jiao Tong University, China.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Popov, Sergei Yu
    KTH Royal Institute of Technology, Sweden.
    Chen, Jiajia
    KTH Royal Institute of Technology, Sweden.
    Lourdudoss, Sebastian
    KTH Royal Institute of Technology, Sweden.
    4 Gbps PAM-4 and DMT Free Space Transmission using a 4.65-pm Quantum Cascaded Laser at Room Temperature2017In: European Conference on Optical Communication, ECOC, Institute of Electrical and Electronics Engineers Inc. , 2017, p. 1-3Conference paper (Refereed)
    Abstract [en]

    We experimentally demonstrate 4Gbps PAM-4 and DMT transmissions using a quantum cascaded laser (QCL) emitting at mid-wavelength infrared of 4.65μm and a commercial infrared photovoltaic detector. The QCL is directly modulated and operated at room temperature with Peltier Cooling.

  • 14003.
    Pang, Xiaodan
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Technology, Sweden.
    Van Kerrebrouck, Joris
    Ghent University, Belgium.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Lin, Rui
    KTH Royal Institute of Technology, Sweden; Huazhong University of Science and Technology, China.
    Udalcovs, Aleksejs
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Zhang, Lu
    KTH Royal Institute of Technology, Sweden.
    Spiga, Silvia
    Technical University of Munich, Germany.
    Amann, Markus C.
    Technical University of Munich, Germany.
    Van Steenberge, Geert
    Ghent University, Belgium.
    Gan, Lin
    Huazhong University of Science and Technology, China.
    Tang, Ming
    Huazhong University of Science and Technology, China.
    Fu, Songnian
    Huazhong University of Science and Technology, China.
    Schatz, Richard
    KTH Royal Institute of Technology, Sweden.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Popov, Sergei
    KTH Royal Institute of Technology, Sweden.
    Liu, Deming
    Huazhong University of Science and Technology, China.
    Tong, Weijun
    YOFC Yangtze Optical Fiber and Cable, China.
    Torfs, Guy
    Ghent University, Belgium.
    Bauwelinck, Johan
    Ghent University, Belgium.
    Yin, Xin
    Ghent University, Belgium.
    Chen, Jiajia
    KTH Royal Institute of Technology, Sweden.
    High-speed SDM interconnects with directly-modulated 1.5-μm VCSEL enabled by low-complexity signal processing techniques2018In: Advanced Photonics 2018 (BGPP, IPR, NP, NOMA, Sensors, Networks, SPPCom, SOF) OSA Technical Digest (online) (Optical Society of America, 2018), paper SpTh2G.4, 2018, article id SpTh2G.4Conference paper (Refereed)
    Abstract [en]

    We report on our recent work in supporting up to 100 Gbps/λ/core transmissions with a directly modulated 1.5-μm single mode VCSEL and multicore fiber, enabled by low-compleixty pre- and post- digital equalizations.

  • 14004.
    Pang, Xiodang
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Gaiarin, Simone
    DTU Technical University of Denmark, Denmark.
    Kakkar, Aditya
    KTH Royal Institute of Technology, Sweden.
    Navarro, Jaime Rodrigo
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Iglesias Olmedo, Miguel
    KTH Royal Institute of Technology, Sweden.
    Schatz, Ricard
    KTH Royal Institute of Technology, Sweden.
    Udalcovs, Aleksejs
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Westergren, Urban
    KTH Royal Institute of Technology, Sweden.
    Zibar, Darko
    DTU Technical University of Denmark, Denmark.
    Popov, Sergei
    KTH Royal Institute of Technology, Sweden.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Experimental Study of 1.55-μ m EML-Based Optical IM/DD PAM-4/8 Short Reach Systems2017In: IEEE Photonics Technology Letters, ISSN 1041-1135, E-ISSN 1941-0174, Vol. 29, no 6, p. 523-526, article id 7839925Article in journal (Refereed)
    Abstract [en]

    We experimentally evaluate high-speed intensity modulation/direct detection (IM/DD) transmissions with a 1.55-μ text broadband electro-Absorption modulated laser and pulse amplitude modulations (PAM). We demonstrate 80 Gb/s/ λ PAM-4 and 96 Gb/s/ λ PAM-8 transmissions with low-complexity digital equalizers at the receiver. Performance comparison with different types of equalizers are performed, including linear symbol-spaced feed-forward equalizer (FFE), fractional (half-symbol) spaced FFE and decision feedback equalizer (DFE), with different tap number. It is found that for both cases, a 6-Tap symbol-spaced FFE is sufficient to achieve a stable performance with bit-error-rate below the 7% overhead hard decision forward error correction (7%-OH HD-FEC) threshold over a 4 km standard single mode fiber link. Practical considerations including comparison between adaptive and static equalizer implementation and tolerable fiber chromatic dispersion are discussed.

  • 14005.
    Pangborn, J.
    et al.
    SIK – Svenska institutet för konserveringsforskning.
    Eriksson, F.
    Remi, K.
    Simplified sialometer for continousweight monitoring of salivary secretion1971In: Journal of Dental Research, Vol. 50, no 6, p. 1689-Article in journal (Refereed)
  • 14006.
    Pangborn, R M
    SIK – Svenska institutet för konserveringsforskning.
    Concepts in sensory analysis of foods1973Report (Refereed)
  • 14007.
    Pangborn, R M
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, SIK – Svenska institutet för konserveringsforskning.
    Food habits of the Americas1971Report (Refereed)
  • 14008.
    Pangborn, Rose-Marie
    et al.
    SIK – Svenska institutet för konserveringsforskning.
    Berggren, B.
    Human parotid secretion in response to pleasant and unpleasant odorants1973In: Psychophysiology, Vol. 10, no 3, p. 231-237Article in journal (Refereed)
  • 14009.
    Pangborn, Rose-Marie
    et al.
    SIK – Svenska livmedelsinstitutet.
    Lundgren, Birgit
    SIK – Svenska livmedelsinstitutet.
    Salivary secretion in response to mastication of crisp bread1977In: Journal of Texture Studies, Vol. 8, p. 463-472Article in journal (Refereed)
  • 14010.
    Pangborn, Rose-Marie
    et al.
    SIK – Svenska livmedelsinstitutet.
    Lundgren, Birgit
    SIK – Svenska livmedelsinstitutet.
    Drake, Birger
    SIK – Svenska livmedelsinstitutet.
    Nilsson, U.
    Effects of light and sound on parotid secretion and taste perception in response to sodium chloride1978In: Chemical Senses, Vol. 3, no 1, p. 81-92Article in journal (Refereed)
    Abstract [en]

    Salivary secretion in response to solutions of 1.6% NaCl was slightly, but not significantly lower under red than under white illumination, and when wearing earphones which delivered intermittent "kitchen" noise, or the monotonous noise of a siren. Gustatory responses from the same subjects to a 15-sample concentration series of NaCl indicated that neither discrimination nor perceived intensity of saltiness was significantly affected by the illumination or by the kitchen noise. Fitting of a smooth, sigmoid line to the group's discrimination data gave a value of 0.012% NaCl for the 75% correct level (50% above chance) and of 0.08% NaCl for 100% identification. The subjects showed no systematic relationship among salivary flow rate, discrimination, or perceived intensity.Contrary to previous findings, neither the light nor the noise resulted in significantly lowered responses in 10 out of 12 subjects in the salivation tests, nor in 45 out of 52 trials (13 subjects × 4 test conditions) in the taste tests. It appears that experienced subjects adapt well to systematic environmental distractions, which do not adversely affect their performance of simple perceptual tasks. © 1978 Information Retrieval Limited.

  • 14011.
    Pang, Xiaodan
    et al.
    KTH Royal Institute of Technology, Sweden.
    Kerrebrouck, Joris Van
    Ghent University, Belgium.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Lin, Rui
    KTH Royal Institute of Technology, Sweden.
    Udalcovs, Aleksejs
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Zhang, Lu
    KTH Royal Institute of Technology, Sweden.
    Spiga, Silvia
    Technical University of Munich, Germany.
    Amann, Markus C
    Technical University of Munich, Germany.
    Steenberge, Geert Van
    Ghent University, Belgium.
    Gan, Lin
    Huazhong University of Science and Technology, China.
    Tang, Ming
    Huazhong University of Science and Technology, China.
    Fu, Songnian
    Huazhong University of Science and Technology, China.
    Schatz, Richard
    KTH Royal Institute of Technology, Sweden.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Popov, Sergei
    KTH Royal Institute of Technology, Sweden.
    Liu, Deming
    Huazhong University of Science and Technology, China.
    Tong, Weijun
    YOFC Yangtze Optical fiber and Cable, China.
    Torfs, Guy
    Ghent University, Belgium.
    Bauwelinck, Johan
    Ghent University, Belgium.
    Yin, Xin
    Ghent University, Belgium.
    Chen, Jiajia
    KTH Royal Institute of Technology, Sweden.
    7×100 Gbps PAM-4 Transmission over 1-km and 10-km Single Mode 7-core Fiber using 1.5-μm SM-VCSEL2018In: Optical Fiber Communication Conference OSA Technical Digest (online) (Optical Society of America, 2018), paper M1I.4, 2018Conference paper (Refereed)
    Abstract [en]

    100 Gbps/λ/core PAM-4 transmission is successfully demonstrated over 1-km and 10-km single mode 7-core fiber links, enabled by directly modulated 1.5-μm single mode VCSEL of 23 GHz modulation bandwidth with pre- and post- digital equalizations.

  • 14012.
    Pang, Xiaodan
    et al.
    KTH Royal Institute of Technology, Sweden.
    Zhang, Li
    KTH Royal Institute of Technology, Sweden.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Udalcovs, Aleksejs
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Lin, Rui
    KTH Royal Institute of Technology, Sweden.
    Schats, Richard
    KTH Royal Institute of Technology, Sweden.
    Xiao, Shilin
    Shanghai Jiao Tong Universuity, China.
    Hu, Weisheng
    Shanghai Jiao Tong Universuity, China.
    Popov, Sergei
    KTH Royal Institute of Technology, Sweden.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Chen, Jiajia
    KTH Royal Institute of Technology, Sweden.
    Key technologies to enable terabit-scale digital radio-over-fiber systems2019In: Proceedings of SPIE - The International Society for Optical Engineering, 2019Conference paper (Refereed)
    Abstract [en]

    With the approach of the 5G era, stringent requirements are imposed on the data transport solutions, including both of the supported transmission reach and the capacity. Radio-over-fiber technologies are considered to be promising candidates to cope with both aspects, owing to the low-loss and broad-bandwidth nature of the optical fibers. Meanwhile with such optical transport solutions, signals can be collected from the distributed remote radio sites and processed in a centralized manner. In this report, we target on the digital radio-over-fiber systems, and discuss about several key technologies, focusing on the aspects of coding and transmission, which could potentially enable terabit-scale data transport.

  • 14013.
    Pansch, Christian
    et al.
    GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany; University of Gothenburg, Sweden.
    Jonsson, Per R.
    University of Gothenburg, Sweden.
    Berglin, Mattias
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Pinori, Emiliano
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Wrange, Anna-Lisa
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    A new flow-through bioassay for testing low-emission antifouling coatings2017In: Biofouling (Print), ISSN 0892-7014, E-ISSN 1029-2454, Vol. 33, no 8, p. 613-623Article in journal (Refereed)
    Abstract [en]

    Current antifouling (AF) technologies are based on the continuous release of biocides into the water, and consequently discharge into the environment. Major efforts to develop more environmentally friendly coatings require efficient testing in laboratory assays, followed by field studies. Barnacles are important fouling organisms worldwide, increasing hydrodynamic drag on ships and damaging coatings on underwater surfaces, and thus are extensively used as models in AF research, mostly in static, laboratory-based systems. Reliable flow-through test assays for the screening of biocide-containing AF paints, however, are rare. Herein, a flow-through bioassay was developed to screen for diverse low-release biocide paints, and to evaluate their effects on pre- and post-settlement traits in barnacles. The assay distinguishes between the effects from direct surface contact and bulk-water effects, which are crucial when developing low-emission AF coatings. This flow-through bioassay adds a new tool for rapid laboratory-based first-stage screening of candidate compounds and novel AF formulations.

  • 14014. Papadakis, Ioannis
    et al.
    Magnusson, Bertil
    YKI – Ytkemiska institutet.
    Metrology in Chemistry and Traceability of Analytical Measurement Results: Chapter 102010In: Quality Assurance in Analytical Chemistry : Training and Teaching / [ed] Wenclawiak, Bernd W., Koch, Michael, Hadjicostas, Evsevios, Springer Berlin/Heidelberg, 2010, 2nd, p. 201-213Chapter in book (Refereed)
  • 14015.
    Papatheocharous, Efi
    RISE - Research Institutes of Sweden, ICT, SICS.
    Challenges in Software Ecosystems and Product Development2018In: Software Business, Platforms, and Ecosystems: Fundamentals of Software Production Research Report, 2018Conference paper (Refereed)
    Abstract [en]

    The German computer science pioneer Karl Steinbuch in 1966 remarked: “In a few decades time, computers will be inter-woven into almost every industrial product.” The increasing prevalence of software ecosystems and platforms today calls for the ability to augment solutions and support an emerging portfolio of leading technology solutions and trends. It is unquestionable to design or use any software technology without taking into account digitalisation trends the emerging technological innovations (e.g., Big Data, Internet of Things, Systems of Systems) and without considering standing on the shoulders of a multitude of layers of platforms and ecosystems. In our research we investigate efficient ways to organise and carry out product development in software ecosystems with the target to satisfy mutual and conflicting requirements from the involved parties. This led to the formulation of the overall research questions (RQs): RQ1. What are the implications on the business models of the different actors, when moving from a traditional supply chain to a dynamic SECO? RQ2. What are the options for improved design of product architectures to handle the contradictory requirements of openness, flexibility and dependability, and to allow efficient product line management? We identified challenges with respect to 3 categories: a) organizational, b) technical, and c) business and use a schema to conceptualise an ecosystem for Federated Embedded 1 8 1 8 2 182 18182 – Software Business, Platforms, and Ecosystems Systems encompassing of four layers: actors, business processes, services and components. We described in an explorative case study (based on interviews with 15 senior staff members at 9 companies related to Embedded Systems) our findings mapped according to the Business Model Canvas (BMC) to highlight the interrelated parts and characteristics of the domain. Openness in SECO was evaluated in 7 companies including 8 practitioners taking into account their practices and methods. Moreover, we target efficient and informed architecture formulation through the selection of existing components and services, and fast architectural adaptations which is crucial for companies’ success, with a systematic approach in the decision-making process with respect to components, services and platforms.

  • 14016.
    Papatheocharous, Efi
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Embracing cognitive factors and fuzzy logic in adaptive interactive systems2013In: International Journal of Engineering Intelligent Systems, Vol. 21, p. 1-18Article in journal (Refereed)
    Abstract [en]

    The increased demand of services on the Web to satisfy the diverse characteristics of users have resulted in a plethora of applications that aim to provide personalized services based on the heterogeneous needs and preferences of users. With the aim to enhance and support the personalization process of Web applications, an innovative adaptation framework is proposed embracing cognitive factors of users which serve as the user model, and Computational Intelligence techniques that decide on the adaptation effects of Web applications for providing a personalized user experience. The user model is based on a series of psychometric measures which capture particular cognitive factors of users, and the adaptation mechanism includes the utilization of Artificial Neural Networks and Fuzzy Logic for exploiting the benefits of intelligent classification and partial truth in the adaptation process. The proposed method has been evaluated with a user study that has revealed a main effect of cognitive factors of users on the adaptation of Web content and functionality since users were more efficient and effective in completing tasks in the adapted than the non-adapted version of the same environment.

  • 14017.
    Papatheocharous, Efi
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Integrating Human Factors and Semantic Mark-ups in Adaptive Interactive Systems2014In: Open Journal of Web Technologies (OJWT), Vol. 1, p. 1-12Article in journal (Refereed)
    Abstract [en]

    This paper focuses on incorporating individual differences in cognitive processing and semantic markups in the context of adaptive interactive systems. In particular, a semantic Web-based adaptation framework is proposed that enables Web authors to enrich content and functionality of Web environments with semantic markups, which are further processed and reconstructed by an adaptation mechanism based on cognitive factors of users. Main aim of this work is to investigate the added value of personalizing content and functionality of Web environments based on the unique cognitive characteristics of users. Accordingly, a user study has been conducted that entailed a psychometric-based survey for extracting users’ cognitive characteristics, combined with a real usage scenario of an existing commercial Web environment that was enriched with semantic markups and was personalized through different adaptation effects. The initial results obtained provide interesting insights in the design and deployment of adaptive interactive systems based on cognitive factors and semantic markups.

  • 14018.
    Papatheocharous, Efi
    et al.
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Andersson, Jesper
    Axelsson, Jakob
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Ecosystems and Open Innovation for Embedded Systems: A Systematic Mapping Study2015In: Software Business, Springer International Publishing , 2015, 11, Vol. 210, p. 81-95Conference paper (Refereed)
    Abstract [en]

    This paper surveys work on ecosystems and open innovation of systems in the context of software engineering for embedded systems. The primary research goal is to develop a research agenda based on the topics identified within the research publications on the topic. The agenda is based on a systematic mapping study of 260 publications obtained from digital libraries and is influenced by a set of areas of interest, i.e., product lines, open source, third party, business models, open innovation, and strategy. The results from the study include analysis of the type of research conducted in the field, its origin and research contribution. The study identifies the need for more solutions to specific open innovation problems such as mapping business models to technical platforms; defining open ecosystem processes that foster open innovation; and improving how ecosystem players can leverage on tool support for open innovation. A direction for future research is also provided.

  • 14019.
    Papatheocharous, Efi
    et al.
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Andreou, Andreas
    Evidence of Agile Adoption in Software Organizations: An Empirical Survey2013Conference paper (Refereed)
    Abstract [en]

    This paper aims at empirically investigating the levels of agile adoption by software development organizations in comparison with the type of practices followed, the business sectors and the countries of origin, as well as revealing the geographical organization and distribution of teams both within agile and traditional development environments. Through a dedicated survey conducted, the paper also discovers, analyzes and presents the business strategies, levels of expertise, benefits and concerns of agile adoption within the various participating organizations. The results obtained indicate that agile methods seem to offer opportunities for improved products in terms of quality and suggest a number of critical factors that affect the software process and the adoption of agile methods in general.

  • 14020.
    Papatheocharous, Efi
    et al.
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Andreou, Andreas S
    Empirical evidence and state of practice of software agile teams2014In: Journal of Software: Evolution and Process, Vol. 26, no 9, p. 855-866Article in journal (Refereed)
  • 14021.
    Papatheocharous, Efi
    et al.
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Axelsson, Jakob
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Andersson, Jesper
    Issues and Challenges in Ecosystems for Federated Embedded Systems2013Conference paper (Refereed)
    Abstract [en]

    This paper discusses how Systems of Systems (SoS) can be constructed by linking together embedded computers in constituent systems to create complex but more flexible and adaptable systems. The approach of software system development is called Federated Embedded Systems (FES) and their revolved ecosystem of players is presented, aiming to ensure quality in engineering SoS. Ecosystems for Federated Embedded Systems (EcoFES) comprise a new area of research that scales component-based software development for embedded software into new dimensions. The proposed ecosystem dimension introduces an open, flexible and adaptable SoS architecture for improving the process of FES development. In the paper, we identify some architectural challenges and discuss the implications of scaling from a closed ecosystem to an open one, providing open collaboration and innovation in the context of FES.

  • 14022.
    Papatheocharous, Efi
    et al.
    RISE - Research Institutes of Sweden, ICT, SICS.
    Belk, Marios
    Nyfjord, Jaana
    RISE - Research Institutes of Sweden, ICT, SICS.
    Germanakos, Panagiotis
    Samaras, George
    Personalised continuous software engineering2014In: Proceedings of the 1st International Workshop on Rapid Continuous Software Engineering, 2014, p. 57-62Conference paper (Refereed)
  • 14023.
    Papatheocharous, Efi
    et al.
    RISE - Research Institutes of Sweden, ICT, SICS. University of Cyprus, Cyprus.
    Bibi, Stamatia
    University of Western Macedonia, Greece.
    Stamelos, Ioannis
    Aristotle University, Greece.
    Andreou, Andreas S
    Cyprus University of Technology, Cyprus.
    An investigation of effort distribution among development phases: A four-stage progressive software cost estimation model2017In: Journal of Software: Evolution and Process, ISSN 2047-7473, E-ISSN 2047-7481, Vol. 29, no 10, article id e1881Article in journal (Refereed)
    Abstract [en]

    Software cost estimation is a key process in project management. Estimations in the initial project phases are made with a lot of uncertainty that influences estimation accuracy which typically increases as the project progresses in time. Project data collected during the various project phases can be used in a progressive time-dependent fashion to train software cost estimation models. Our motivation is to reduce uncertainty and increase confidence based on the understanding of patterns of effort distributions in development phases of real-world projects. In this work, we study effort distributions and suggest a four-stage progressive software cost estimation model, adjusting the initial effort estimates during the development life-cycle based on newly available data. Initial estimates are reviewed on the basis of the experience gained as development progresses and as new information becomes available. The proposed model provides an early, a post-planning, a post-specifications, and a post-design estimate, while it uses industrial data from the ISBSG (R10) dataset. The results reveal emerging patterns of effort distributions and indicate that the model provides effective estimations and exhibits high explanatory value. Contributions in lessons learned and practical implications are also provided.

  • 14024.
    Papatheocharous, Efi
    et al.
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Franke, Ulrik
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Decision-Making in Automotive Software Development: An Observational Stud2016In: New Trends in Software Methodologies, Tools and Techniques / [ed] Hamido Fujita, George Angelos Papadopoulos, IOS Press, 2016, Vol. 286, p. 59-68Conference paper (Refereed)
    Abstract [en]

    This paper reports results from an independent observational study of an automotive software development research project. The study is carried out as a monitoring activity of the project, which is inexpensive but still representative of real automotive software development cases, thus providing the basis for more rigorous studies. The objective is to take initial steps to improve our understanding of architectural decision-making in the development of software in the automotive domain. The key findings summarize issues surfacing during the development process related to the problem articulation and formulation, the impact of participant experience, the definition of requirements, the decision process, and the effect of the decisions made on the system architecture evolution. The paper offers some insights that can be useful to gain understanding of how decisions are typically made in real settings, i.e., based on gut-feeling, which is important when designing decision support systems for architectural design decisions.

  • 14025.
    Papatheocharous, Efi
    et al.
    RISE - Research Institutes of Sweden, ICT, SICS.
    Frécon, Emmanuel
    RISE - Research Institutes of Sweden, ICT, SICS.
    Kaizer, Christian
    Virtual Vehicle Research Center, Austria.
    Festl, Andreas
    Virtual Vehicle Research Center, Austria.
    Stocker, Alexander
    Virtual Vehicle Research Center, Austria.
    Towards a generic IoT platform for data-driven vehicle services2018In: / [ed] IEEE, 2018, p. 95-100, article id 8519505Conference paper (Refereed)
    Abstract [en]

    Advances in the field of engineering have resulted in vehicles becoming a digitised source of data from which scenarios of Quantified Vehicles emerge. Even though the benefits and range of emerging services are ample, several challenges cap the extent of opportunities, such as determining the business benefits, as well as constructing and operating an independent, scalable, and flexible platform ensuring e.g., privacy, accountability. In our work in progress paper, we propose a conceptual architecture of a generic IoT platform for enabling such data-driven services for the vehicle domain, while considering important characteristics, such as data security and privacy, improved service operations, safety and value creation for end-users. We then describe how this platform can be demonstrated, including the vehicle gateway device (Vehicle Data Logger) capturing the vehicle data, to finally enable a set of useful and usable data-driven services for vehicle drivers and other stakeholders.

  • 14026.
    Papatheocharous, Efi
    et al.
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Michalas, Antonis
    RISE, Swedish ICT, SICS.
    Gehrmann, Christian
    RISE, Swedish ICT, SICS, Security Lab.
    A Holistic Data Privacy and Security by Design Platform-as-a-Service Framework Introducing Distributed Encrypted Persistence in Cloud-based Applications2015Conference paper (Refereed)
    Abstract [en]

    PaaSword’s vision is three-fold; i) maximize and fortify the trust of individual, professional and corporate customers to Cloud-enabled services and applications; ii) safeguard both corporate and personal sensitive data stored on Cloud infrastructures and Cloud-based storage services, and iii) enable the acceleration of Cloud computing technologies adoption and paradigm shift in the European industry. PaaSword will introduce a holistic data privacy and security by design framework enhanced by sophisticated context-aware policy access models and robust policy access, decision, enforcement and governance mechanisms, which will enable the implementation of secure and transparent Cloud-based applications and services, that will maintain a fully distributed and totally encrypted data persistence layer, and, thus, will ensure data protection, integrity and confidentiality, even in the case wherein there is no control over the underlying third-party Cloud resources utilised.

  • 14027.
    Papatheocharous, Efi
    et al.
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Nyfjord, Jaana
    RISE - Research Institutes of Sweden, ICT, SICS.
    Papageorgiou, Elpiniki
    Fuzzy Cognitive Maps as Decision Support Tools for Investigating Critical Agile Adoption Factors2013Conference paper (Refereed)
    Abstract [en]

    A lot of discussion on how to efficiently develop software by using agile methods in enterprises and what kind of implications enterprises face on their path towards enterprise agility exists in nowadays. This paper describes how Fuzzy Cognitive Maps (FCM) can be used as Computational Intelligence (CI) tools for Decision Support (DS) in reducing the risks of the implications in this adaptation or transformation process. Particularly, FCM are used in understanding the effect of a set of critical Agile Adoption Factors (AAF) proposed in literature in the success of adopting agile. A set of preliminary experiments have been conducted to show that AAF can be evaluated with the use of FCM and their effect on adoption success is validated in three specific contexts. The scenarios investigated show that a critical implication is corporate bureaucracy. Also, results indicate that some enablers are the project teams’ personal traits, such as collaborative attitude and readiness to change, as well as, the customers’ level of commitment. The proposed FCM model provides an insight on the usefulness of the method for assessing agile transformation success.

  • 14028.
    Papatheocharous, Efi
    et al.
    RISE - Research Institutes of Sweden, ICT, SICS.
    Petersen, Kai
    RISE - Research Institutes of Sweden, ICT, SICS.
    Axelsson, Jakob
    RISE - Research Institutes of Sweden, ICT, SICS.
    Wohlin, Claes
    Blekinge Institute of Technology, Sweden.
    Carlson, Jan
    Malardalen University, Sweden.
    Ciccozzi, Federico
    Malardalen University, Sweden.
    Sentilles, Séverine
    Malardalen University, Sweden.
    Cicchetti, Antonio
    Malardalen University, Sweden.
    The GRADE Decision Canvas for Classification and Reflection on Architecture Decisions2017In: Proceedings of the 12th International Conference on Evaluation of Novel Approaches to Software Engineering - Volume 1: ENASE, 2017, p. 187-194Conference paper (Refereed)
    Abstract [en]

    This paper introduces a decision canvas for capturing architecture decisions in software and systems engineering. The canvas leverages a dedicated taxonomy, denoted GRADE, meant for establishing the basics of the vocabulary for assessing and choosing architectural assets in the development of software-intensive systems. The canvas serves as a template for practitioners to discuss and document architecture decisions, i.e., capture, understand and communicate decisions among decision-makers and to others. It also serves as a way to reflect on past decision-making activities devoted to both tentative and concluding decisions in the development of software-intensive systems. The canvas has been assessed by means of preliminary internal and external evaluations with four scenarios. The results are promising as the canvas fulfills its intended objectives while satisfying most of the needs of the subjects participating in the evaluation.

  • 14029.
    Papatheocharous, Efi
    et al.
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Petersen, Kai
    Cicchetti, Antonio
    Sentilles, Severine
    Shah, Syed
    RISE, Swedish ICT, SICS, Security Lab.
    Gorschek, Tony
    Decision support for choosing architectural assets in the development of software-intensive systems: The GRADE taxonomy2015Conference paper (Refereed)
  • 14030.
    Papatheocharous, Efi
    et al.
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory.
    Sentilles, Severine
    Ciccozzi, Frederico
    Petersen, Kai
    A Property Model Ontology2016In: SEAA 2016: 42nd Euromicro Conference on Software Engineering and Advanced Applications, IEEE Press, 2016Conference paper (Refereed)
    Abstract [en]

    Efficient development of high quality software is tightly coupled to the ability of quickly taking complex decisions based on trustworthy facts. In component-based software engineering, the decisions related to selecting the most suitable component among functionally-equivalent ones are of paramount importance. Despite sharing the same functionality, components differ in terms of their extra-functional properties. Therefore, to make informed selections, it is crucial to evaluate extra-functional properties in a systematic way. To date, many properties and evaluation methods that are not necessarily compatible with each other exist. The property model ontology presented in this paper represents the first step towards providing a systematic way to describe extra-functional properties and their evaluation methods, and thus making them comparable. This is beneficial from two perspectives. First, it aids researchers in identifying comparable property models as a guide for empirical evaluations. Second, practitioners are supported in choosing among alternative evaluation methods for the properties of their interest. The use of the ontology is illustrated by instantiating a subset of property models relevant in the automotive domain.

  • 14031.
    Papatheocharous, Efi
    et al.
    RISE - Research Institutes of Sweden, ICT, SICS.
    Wnuk, Krzysztof
    Blekinge Institute of Technology, Sweden.
    Petersen, Kai
    Blekinge Institute of Technology, Sweden.
    Sentilles, Severine
    Mälardalen University, Sweden.
    Cicchetti, Antonio
    Mälardalen University, Sweden.
    Gorschek, Tony
    Blekinge Institute of Technology, Sweden.
    Shah, Syed M. A.
    RISE - Research Institutes of Sweden, ICT, SICS.
    The GRADE taxonomy for supporting decision-making of asset selection in software-intensive system development2018In: Information and Software Technology, ISSN 0950-5849, E-ISSN 1873-6025, Vol. 100, p. 1-17Article in journal (Refereed)
    Abstract [en]

    Context: The development of software-intensive systems includes many decisions involving various stakeholders with often conflicting interests and viewpoints. Objective: Decisions are rarely systematically documented and sporadically explored. This limits the opportunity for learning and improving on important decisions made in the development of software-intensive systems. Method: In this work, we enable support for the systematic documentation of decisions, improve their traceability and contribute to potentially improved decision-making in strategic, tactical and operational contexts. Results: We constructed a taxonomy for documentation supporting decision-making, called GRADE. GRADE was developed in a research project that required composition of a common dedicated language to make feasible the identification of new opportunities for better decision support and evaluation of multiple decision alternatives. The use of the taxonomy has been validated through thirty three decision cases from industry. Conclusion: This paper occupies this important yet greatly unexplored research gap by developing the GRADE taxonomy that serves as a common vocabulary to describe and classify decision-making with respect to architectural assets.

  • 14032.
    Papworth, Nigel
    RISE, Swedish ICT, Interactive Institute.
    iSpooks: an audio focused game design2010Conference paper (Refereed)
    Abstract [en]

    This paper is an attempt to analyse and explain the ‘design decision making’ behind iSpooks, an audio based adventure game for the iPhone. The game utilizes audio as its principle mechanism for driving the gameplay. The design and production team were therefore forced to look at and reconsider the ways in which a mobile phone game works. This resulted in some innovative and previously untried techniques in the design process and technical solutions developed for the project. It also, and perhaps more importantly, addressed and analysed aspects of mobile phone users behaviour in relation to these innovations. This paper covers the research and conclusions that lead to the final game design, and describes aspects such as, sound design, designing for the casual gamer, finding appropriate narrative forms and creating non-visual immersion.

  • 14033.
    Papworth, Nigel
    et al.
    RISE, Swedish ICT, Interactive Institute.
    Liljedahl, Mats
    RISE, Swedish ICT, Interactive Institute.
    Designing Audio-based networked games to maximize player immersion2007Conference paper (Refereed)
    Abstract [en]

    This is a description of a practical experiment in alternative game design, intended to test and define a new kind of player experience in mobile/net gaming. This ‘Audio-mostly’ concept is created as a test-bed and prototype for sound-based game applications. The underlying principle lies in expanding the imagination of the user, rather than the graphic capabilities of the platform. It should be noted that this research project was principally concerned with defining the design parameters and aesthetics needed for the creation of effective audio based games, it was never intended as a purely academic investigation of the subject’s reactions to the test bed. To this end, we have chosen to use a less rigid style in presenting this project It should also be noted that an audio-mostly game should not be confused with a game specifically designed for the visually impaired, instead it is a game intended for normally sighted people to be used in situations where audio-based gameplay has an advantage over traditional visual based games (Mobile phones in transit for example).

  • 14034.
    Papworth, Nigel
    et al.
    RISE, Swedish ICT, Interactive Institute.
    Liljedahl, Mats
    RISE, Swedish ICT, Interactive Institute.
    Lindberg, Stefan
    RISE, Swedish ICT, Interactive Institute.
    Beowulf - An Audio Mostly Game2007Conference paper (Refereed)
    Abstract [en]

    This paper stresses the importance and benefits of developing technique that let people use, reflect on and develop their capabilities to move, to imagine and to feel, and not only replace these abilities with computer technology. This paper describes a project that shifts focus from eye to ear in a computer game application in order to start answering questions about sound’s ability to help users create inner, mental pictures and emotional responses to a game world. Can removing components from a computer game concept enhance the experience? Is less more?

  • 14035.
    Papworth, Nigel
    et al.
    RISE, Swedish ICT, Interactive Institute.
    Liljedahl, Mats
    RISE, Swedish ICT, Interactive Institute.
    Lindberg, Stefan
    RISE, Swedish ICT, Interactive Institute.
    Beowulf: A Game Experience Built On Sound Effects2007Conference paper (Refereed)
    Abstract [en]

    A computer game with most of the traditional graphics removed and replaced with a detailed and realistic soundscape, can give immersive gaming experiences. By reducing the graphical, explicit output of information from the game, the player becomes free to concentrate on interpreting the implicit information from a rich sound scape. This process of interpretation seems to have the power to invoke clear inner, mental images in the player, which in turn gives strong and immersive experiences. This paper describes a project that explores some of these mechanisms and points out some new potential directions for computer games and game play design.

  • 14036.
    Papworth, Nigel
    et al.
    RISE, Swedish ICT, Interactive Institute.
    Liljedahl, Mats
    RISE, Swedish ICT, Interactive Institute.
    Lindberg, Stefan
    RISE, Swedish ICT, Interactive Institute.
    Effective interactive design through quick and flexible prototyping2007Conference paper (Refereed)
    Abstract [en]

    One of the problems with designing new and untried applications, is the sheer effort needed to produce a testable prototype. Many projects get bogged down with production problems and hardware/software issues before they can even be tested for their basic functionality. This creates delays and frustrations within the project structure as well as creating unnecessary pressures on the project structure itself. This is equally true for the two main types of prototype/application created in design research: 1. a potential new product 2. a viable test bed to test an hypothosis. This paper investigates approaches, both practical and philosophical, to design processes and construction techniques that endeavour to bypass the most common pitfalls and stumbling blocks to a working prototype. In the main, the paper focuses on designing with ’Audio’ as an effective tool for quick, effective and emotive prototyping. Practical examples, both successful and catastrophic, are used to illustrate these aspects. In specific we will be comparing two audio based games, Journey and Beowulf, looking at their respective weaknesses and strengths. These prototyping techniques are realised, in the main, through easily available tools and recording techniques, based on standard audio-visual techniques. This provides a neat fast-track to developing ideas into viable applications. However while we can utilize a vast array of existing technologies to enable fast proto-typing, the most crucial element in successfully creating testbeds and bringing them before a test group is the intellectual approach to experiment design. Understanding the fundamental processes and isolating the essential questions the application is intended to answer has a direct bearing on our ability to channel available creative and productive energies with the maximum focus. Audio provides us with emotive tools highly suited to performing these kinds of functions. The advantage of taking this approach is a quick, flexible and, not least, economic route to getting vital early answers to practical research problems in IT user-based projects.

  • 14037.
    Pari, Luigi
    et al.
    CREA-IT, Italy.
    Scarfone, Antonio
    CREA-IT, Italy.
    Lundin, Gunnar
    RISE - Research Institutes of Sweden, Bioscience and Materials, Agrifood and Bioscience.
    Gunnarsson, Carina
    RISE - Research Institutes of Sweden, Bioscience and Materials, Agrifood and Bioscience.
    Bergonzoli, Simone
    CREA-IT, Italy.
    Alfano, Vincenzo
    CREA-IT, Italy.
    Lazar, Sandu
    CREA-IT, Italy.
    Suardi, Alessandro
    CREA-IT, Italy.
    Combined harvesting of chaff and straw for bioethanol production: The first experience on wheat in Sweden2018In: European Biomass Conf. Exhib. Proc., 2018, no 26thEUBCE, p. 289-293Conference paper (Refereed)
    Abstract [en]

    The purpose of this work is the evaluation of a harvest chain aimed at incorporating the chaff into the straw bales as consequence of wheat harvest operation. The test was performed in August 2017 in Uppsala, Sweden, using a commercial hybrid combine harvester equipped with a modified chaff spreader and a tractor with round baler. In particular, the chaff spreader was used as chaff recovery system to redirect the chaff into the straw flow during its fall on the ground and get the product admixed in the straw swath. The combine was also used with the recovery systems in “spreading mode” to be experimented as control. A few companies are approaching this engineering challenge, however, as the market of agricultural residues for fuel production is growing, simple and affordable solutions should be identified and commercialized. This paper can be considered as a primary attempt to find a simplified and affordable solution in this direction. The results show different harvesting performances according to machine settings. Indeed, when the recovery system was used, the material falling into the swath and baled was about 340 kg (14%) higher per ha (dry basis). However, respect the amount of biomass potentially available for baling, high harvest losses were identified and indicated the need to repeat the test with other machineries and find further adjustments.

  • 14038.
    Paridari, Kaveh
    et al.
    KTH Royal Institute of Technology, Sweden.
    Nordstrom, Lars
    KTH Royal Institute of Technology, Sweden.
    Sandels, Claes
    RISE - Research Institutes of Sweden, Safety and Transport, Measurement Science and Technology.
    Aggregator strategy for planning demand response resources under uncertainty based on load flexibility modeling2017In: 2017 IEEE International Conference on Smart Grid Communications, SmartGridComm 2017, 2017, p. 338-343Conference paper (Refereed)
    Abstract [en]

    Nowadays, end-users can participate in demand response (DR) programs, and even slight load reductions from many houses can add up to major load shifts in the power system. Aggregators, which act as mediators between end-users and distribution system operator (DSO), play an important role here. The aggregator contracts the end-users for DR programs, plans ahead for times when customers should shift their load, and controls the load shifts in the running time. In this paper, our main focus is on planning the end-users for load shifting. Here, we first define and formulate the flexibilities (e.g., Stamina, repetition, and capacity) related to the dynamic loads such as space heating systems (SHSs) in detached houses. Assuming some end-users being contracted for DR program, based on estimation of their house characteristics and load flexibilities, an algorithm is then proposed to plan the SHSs for load shifting. In this algorithm the states in which a flexible load can be planned, kept in backup, or unavailable are considered by the aggregator. Another algorithm has been proposed here to deal with the different sources of uncertainties (which cause some of the planned SHSs to become unavailable). Numerical results are presented at the end, which discuss performance of the proposed strategy in terms of load flexibilities, load shifts in response to DR signals, and sensitivity analysis. Here, how to estimate the houses characteristics is a difficult issue, and we approximate them based on available models in the literature.

  • 14039. Park, KD
    et al.
    Jarlemark, P
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Mätteknik.
    Multipath characteristics of GPS signals as determined from the Antenna and Multipath Calibration System2002In: Proceedings of the Institute of Navigation GPS 2002, Salt Lake City, USA, 2002, 2002Conference paper (Other academic)
  • 14040. Park, M.S.
    et al.
    Jain, V.
    Lee, E.H.
    Kim, S.H.
    Pettersson, H.
    Wang, Q.
    RISE, Swedish ICT, Acreo.
    Song, J.D.
    Choi, W.J.
    InAs/GaAs p–i–p quantum dots-in-a-well infrared photodetectors operating beyond 200 K2014In: Electronics Letters, ISSN 0013-5194, E-ISSN 1350-911X, Vol. 0, no 23, p. 1731-1733Article in journal (Refereed)
    Abstract [en]

    High-temperature operating performance of p-i-p quantum dots-in-a-well infrared photodetectors (QDIPs) is successfully demonstrated. The optically active region consists of 10 layers of p-doped self-assembled InAs quantum dots (QDs) asymmetrically positioned in In0.15Ga0.85As quantum wells (QWs). The dark current is suppressed by an incorporated superlattice (SL) structure composed of 10 pairs of AlGaAs/GaAs heterostructure. The very low recorded dark current makes the fabricated p-i-p QDIPs suitable for high-temperature operation. The measured photoresponse reveals broad mid-wave infrared (MWIR) detection up to 200 K.

  • 14041. Park, MS
    et al.
    Jain, V
    Lee, EH
    Kim, SH
    Pettersson, H
    Wang, Q
    RISE, Swedish ICT, Acreo.
    Song, JD
    Choi, WJ
    InAs/GaAs p-i-p quantum dots-in-a-well infrared photodetectors operating beyond 200 K2014In: Electronics Letters, ISSN 0013-5194, E-ISSN 1350-911X, Vol. 50, no 23, p. 1731-3Article in journal (Refereed)
  • 14042. Parker, JL
    et al.
    Cho, DL
    Claesson, PM
    YKI – Ytkemiska institutet.
    Plasma modification of mica; forces between fluorocarbon surfaces in water and a nonpolar liquid1989In: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 93, p. 6121-6125Article in journal (Refereed)
    Abstract [en]

    Mica has been exposed to low-temperature water vapor plasma. A combination of reaction and sputtering in the plasma environment alters the surface properties of mica and activates the surface toward with chlorosilanes. The plasma treatment technique causes minimal alteration to the surface smoothness and oscillatory solvation forces were measured in octamethylcyclotetrasiloxane (OMCTS). Reaction of the plasma-treated mica with (tridecaflouro-1,1,2,2-tetrahydrooctyl)-1-dimethylchlorosilane renders the surface hydrophobic. The oscillatory solvation force is removed by surface roughness, due to a low surface density of reacted silane ( one molecule per 5 nm2 as estimated by ESCA) and the forces between thesesurfaces in OMCTS were attractive and in agreement with the force expected from van der Waals theory. The force between two silanated surfaces in water is in good agreement with the force calculated from DLVO theory at separations greater than 50 nm but an additional exponential attraction is observed at smaller separations. The magnitude and decay length of this attraction are in close agreement with those found previously between mica surfaces hydrophobed by Langmuir-Blodgett deposition of surfactant monolayers. Consequently, the hydrophobic interaction observed between surfactant-coated surfaces does not result from instabilities in the surfactant layer.

  • 14043. Parker, JL
    et al.
    Claesson, PM
    YKI – Ytkemiska institutet.
    Forces between hydrophobic silanated glass surfaces1994In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 10, p. 635-639Article in journal (Refereed)
    Abstract [en]

    A novel surface force apparatus has been utilized in order to determine the forces acting between two glass surfaces rendered hydrophobic by silanation. It was found that in pure water the long-range force is due to a repulsive double-layer force. At shorter separations the force is attractive and stronger than expected for a van der Waals attraction. When the pH is lowered to 2, the repulsive double-layer force is insignificant and the measured force is attractive at all separations. The measurable range is about 30 nm. The attractive force decays roughly exponentially with surface separation having a decay length of 5.6 nm, significantly larger than the electrostatic Debye length (3 nm). Thus we conclude that the origin of this attractive force is not electrostatic. The forces acting between one hydrophobic silanated glass surface and one untreated glass surface at distances greater than 3 nm are dominated by a repulsive double-layer force. At shorter separation the force turns attractive. The attractive force observed is slightly larger than that expected for a van der Waals force but significantly smaller than that observed between two hydrophobic surfaces or between mica and hydrophobized mica.

  • 14044. Parker, JL
    et al.
    Claesson, PM
    YKI – Ytkemiska institutet.
    Attard, P
    Bubbles, cavities, and the long-ranged attraction between hydrophobic surfaces1994In: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 98, p. 8468-8480Article in journal (Refereed)
    Abstract [en]

    Measurements of the forces in water between neutral hydrophobic surfaces prepared by covalent modification of glass are presented. The surfaces are stable under a variety of conditions including high temperature, high salt concentrations and with added ethanol. The forces between these surfaces have been studied under all of these different conditions. In water the force is attractive at very large surface separations, and discontinuities or steps are present in the force curves. It is suggested that the steps at the onset of the force are due to the bridging of submicroscopic bubbles or cavities between the surfaces and that it is their consequent growth with decreasing separation that causes the long-range attraction between hydrophobic surfaces. Electrolyte has a negligible effect on the range and strength of the measured forces, except at very high salt concentrations where the strength of the attractive forces and the adhesion between the surfaces increases slightly. The addition of ethanol reduces both the strength of the long range forces and the adhesion between the surfaces. On the basis of the comparison between these results and earlier measurements, it appears that the attraction does not obey the Derjaguin approximation. Forces were also measured in the presence of a microscopic vapor cavity created by first bringing the surfaces into contact.

  • 14045. Parker, JL
    et al.
    Claesson, PM
    YKI – Ytkemiska institutet.
    Cho, DL
    Ahlberg, A
    Tidblad, J
    Blomberg, E
    YKI – Ytkemiska institutet.
    Plasma modification of mica1990In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 134, p. 449-458Article in journal (Refereed)
    Abstract [en]

    When mica is exposed to a low temperature nonpolymer-forming plasma the surface structure is altered by a combination of sputtering and chemical reaction with reactive species in the plasma. The chemical composition of the surface is altered without a significant increase in surface roughness under optimal conditions. The effect of the plasma process parameters (exposure time, power, flow rate, and pressure) on the extent of surface modification has been investigated by means of ESCA and contact angle measurements. After exposure to water vapor plasma the mica surface becomes reactive to silanation with chlorosilanes in the gas phase. The durability of mica surfaces modified by plasma treatment and subsequent reaction with some chlorosilanes has been investigated. The forces between water plasmatreated surfaces after silanation have been measured using a surface force apparatus.

  • 14046. Parker, JL
    et al.
    Claesson, PM
    YKI – Ytkemiska institutet.
    Wang, J-H
    Yasuda, HK
    Surface forces between plasma polymer films1994In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 10, p. 2766-2773Article in journal (Refereed)
    Abstract [en]

    The surface properties of two different plasma polymer coatings were investigated by means of ESCA wetting studies, and surface force measurements. The plasma polymer films formed from hexamethyldisiloxane (HMDSO) monomers were found to be very smooth. This made it possible to measure the attractive van der Waals interaction between HMDSO-coated sur,faces in air. When the HMDSO-coated surfaces were immersed in water, they initially appeared strongly hydrophobic with an advancing and recedingcontactangle of 109° and 98°, respectively. Nevertheless, nolongrange zhydrophobic"interaction was observed. The HMDSO coating became slightly more hydrophilic when kept in an aqueous phase for a prolonged time, indicating migration/reorientation of polar groups to the surface. Surface force me asurements in water cle arly de monstrat ed the appe arance of el ectro static charge s and extending polymer tails as a result of a prolonged exposure to water. Plasma polymer coatings of C2F4 or C2F6 deposited on top of a plasma polymer of CH4 were also studied. The forces between such a polymer and a glass surface are on the first approach in air characteristic of a van der Waals force. However, the attraction increases as the surfaces are brought together repeatedly. The increase in the long range attraction is a result of contact electrification due to electron transfer from glass to the fluorocarbon surface. It was found that in aqueous environment the C2F4 plasma polymer surface is significantly less smooth and less stable than the HMDSO plasma polymer surface.

  • 14047. Parker, JL
    et al.
    Rutland, MW
    YKI – Ytkemiska institutet.
    Time-dependent adhesion between glass surfaces in dilute surfactant solutions1993In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 9, p. 1965-1967Article in journal (Refereed)
    Abstract [en]

    Measurements of surface forces between glass surfaces in very dilute cationic surfactant solutions at pH 10 are presented. As the surfaces approach the forces are purely repulsive and correspond exactly to the interaction of glass surfaces in aqueous solution at the same pH. However, a small adhesion is observed on separation, the magnitude of which is dependent on the time the surfaces are left in contact. The adhesion arises due to adsorption of surfactant in a narrow gap around the contact area and is induced by the favorable interaction of hydrophobic tails across the gap. The time dependence of the adhesion suggests that the adsorption is diffusion limited.

  • 14048. Parker, JL
    et al.
    Yaminsky, VV
    Claesson, PM
    YKI – Ytkemiska institutet.
    Surface forces between glass surfaces in cetyltrimethylammonium bromide solutions1993In: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 97, p. 7706-7710Article in journal (Refereed)
    Abstract [en]

    A new surface apparatus has been used to study the interactions between glass surfaces immersed in CTAB (cetyltrimethylammonium bromide) solutions. At low surfactant concentrations CTAB adsorbs to form a monolayer, and the surfaces become adhesive in contact. At a concentration of 5 x 10-5 M the charge on glass is neutralized, and the surfaces experience an attractive force in excess of that expected from van der Waals interactions. At concentrations just below the critical micelle concentration, CTAB adsorbs to the hydrophobic interface to form loosely packed bilayers, but the surfaces always come to an adhesive minimum. These observations are quite different from those made when mica is used as the substrate. A comparison between the results obtained for the two substrates is made, and the reasons for the differences are discussed. Glass has a lower area per charge compared with mica, and this results in less tightly packed monolayers and in turn bilayers on glass when compared with mica.

  • 14049. Parker, William
    et al.
    Sundström, Björn
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, SP – Sveriges Tekniska Forskningsinstitut / Brandteknik, material (BRm).
    Review of models for predicting the burning behaviour of upholstered furniture: report to the Commission of the European Communities1993Report (Refereed)
  • 14050.
    Parmeggiani, Matteo
    et al.
    KTH Royal Institute of Technology, Sweden.
    Dev, Apurba
    KTH Royal Institute of Technology, Sweden ; Uppsala University, Sweden.
    Björk, Per
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Linnros, Jan
    KTH Royal Institute of Technology, Sweden.
    Electrokinetic-assisted gating in a microfluidic integrated Si nanoribbon ion sensor for enhanced sensitivity2018In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 262, p. 974-981Article in journal (Refereed)
    Abstract [en]

    Using the electrokinetic principle, we demonstrate a novel approach to modulate the response of an ion sensitive silicon-nanoribbon field-effect-transistor, effectively manipulating the device sensitivity to a change in surface potential. By using the streaming potential effect we show that the changes in the surface potential induced by e.g. a pH change can be accurately manipulated in a microfluidic-integrated chip leading to an enhanced response. By varying the flow velocity and the biasing condition along the microfluidic channel, we further demonstrate that the pH response from such a device can also be suppressed or even reversed as a function of the flow velocity and the biasing configuration. Experiments performed with different pH buffer shows that the sensor response can be enhanced/suppressed by several times in magnitude simply by using the streaming potential effects. A mathematical description is also presented for qualitative assessment of the electrokinetic influence on the gate terminal under different biasing condition. The approach presented here shows the prospect to exploit the electrokinetic modulation for developing highly sensitive nanoscale biosensors.

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