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  • 6601.
    Apanasevic, Tatjana
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Factors Influencing the Slow Rate of Penetration of NFC Mobile Payment in Western Europe2013In: the 12th International Conference on Mobile Business (ICMB2013), Berlin, Germany, June 2013, 2013Conference paper (Refereed)
    Abstract [en]

    The NFC technology implemented on the base of contemporary mobile handsets can provide considerable benefits to end-users. However, despite high level of diffusion of mobile phones in Western Europe, the level of penetration of the NFC based mobile payment is low. A considerable number of trials have been initiated, however, large scale deployment of commercial NFC services cannot be seen. This paper identifies and analyzes different factors that influence the slow rate of penetration of NFC based mobile payment in Western Europe.

    This paper presents a qualitative study based on experience of six NFC pilots implemented in Finland, France, Italy, the Netherlands, Norway, and the UK. The research findings confirm that a number of demand and supply barriers negatively affect the rate of the penetration of the NFC payment. The network externalities and the lack of consumer awareness about NFC services were identified as the most important demand side barriers. The most significant supply side barriers are the lack of uniform technological standards, the lack of NFC enabled mobile phones, and the coopetition issue. In addition, the interrelation between mentioned obstacles was identified. This fact means that a delay in the NFC payment’s diffusion is affected not by a single factor, but rather by a set of interrelated factors. The sources of these obstacles are related to the consumer acceptance, the specifics of business environment, and the technology.

  • 6602.
    Apanasevic, Tatjana
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Mobile Payments: Main Trends in the Retail Industry2014In: 25th European Regional Conference of the International Telecommunications Society (ITS), Brussels, Belgium, June 22 - 25, 2014, 2014Conference paper (Refereed)
    Abstract [en]

    The main objective of the ongoing study is to investigate obstacles ans driving forces affecting organization adoption of innovation. In order to that an example of the mobile payments applied in the Swedish retail industry has been used. The main analyzed factors are: adopter characteristics, supplier marketing activity, perceived innovation dcharacteristics, social network, and environmental influences.

    The analysis of case study findings helped to estimate some common trends in the adoption of mobile payment services by retailers. As a result, the analyzed factors were categorized as obstacles or driving forces to adoption of the mobile payments.

  • 6603.
    Apanasevic, Tatjana
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Obstacles to investments in mobile payments: The perspective of merchants: Work in progress2013Conference paper (Refereed)
    Abstract [en]

    The main objective of the ongoing research is to investigate obstacles and driving forces affecting merchants’ decision to invest in mobile payment solutions. The core aim of this paper is to present initial results of a desktop analysis revealing the current market situation, identifying main players, and estimating the structure of investment costs. In order to do that available secondary information was analyzed.

    The conducted analysis served to identify market fragmentation existing in the Swedish market due to existence of a number of competing mobile payment solutions. Another finding allows making conclusion, that retailers select to adopt already existing solutions, rather than developing own. Finally, the size of an organization and financial resources are important when making a decision to invest in a new payment solution.

  • 6604.
    Apanasevic, Tatjana
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Opportunities and challenges of mobile payment services: The perspective of service providers2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

     Mobile payments are transforming the payments industry. These services open up the opportunity for non-banking actors to enter the market. In order to embrace this challenge, banks, traditional payments market players, are forced to launch mobile payments. However, in Europe and most developed economies, a big number of launched services get terminated soon after their introduction in the market. Hence, the ability of different actors to act locally calls for additional research.

    The main objective of this thesis is to broaden knowledge and understanding about the ways mobile payment service providers address the opportunities and challenges of mobile payment services. In order to investigate this problem, this research (i) explores factors stimulating and hindering the introduction of mobile payments using perspectives of different types of service providers (i.e., banks, independent providers, direct operator billing providers, retailers, and public transport companies) and (ii) seeks to explain the importance of these factors for each type of provider.

    The primary data collected using interview method. More than 40 industry representatives in six countries were contacted. The Service, Technology, Organisation, and Finance (STOF) model was used as a theoretical research framework. This is a business modelling framework that specifies a set of critical design issues that have to  be considered within each model’s domain.

    Research findings highlight that the organisation domain is the key domain, which  affects all other domains and has an impact on the general viability of the business model. A comparison of the approaches used by different service providers to address each of the critical design issues helped to identify the factors that are most important within each domain. These factors stimulate or hinder development of a viable business model within each category of service providers.

    This research contributes to a better understanding of challenges and success factors associated with the design of business models for new mobile services and uses the lens of the STOF model. The contributions to the academic research on mobile payments are: (i) collection and analysis of a rich empirical data set on mobile payment services implemented in six Northern European countries, (ii) discussion of a bigger picture by connecting research findings to the context of the existing payment system, (iii) extension  of knowledge on business models for mobile ticketing, and (iv) extension of knowledge on the value of mobile ticketing services in the business-to-business (B2B) context.

  • 6605.
    Apanasevic, Tatjana
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Organizational Acceptance of Mobile Payments2014In: 30th annual International Marketing and Purchasing Conference (IMP 2014), Bordeaux, France, September 4-5, 2014, 2014Conference paper (Refereed)
  • 6606.
    Apanasevic, Tatjana
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Primary data collection: Approaches of service providers towards mobile payments2018Report (Other academic)
    Abstract [en]

    Mobile payments are new services enabled by evolution of information and communication technologies. These services can be provided by different types of actors both banks and non-banks. The understanding of capabilities and limitations of different service providers to act in local markets requires further understanding. Implemented research seeks to extend knowledge in this area. I have implemented research focused on approaches used by different types of service providers including banks, independent providers, operator billing providers, retailers, and public transport companies in six Northern European countries.

    Exploratory part of the research aims to address the following research question: What factors stimulate and hinder the introduction of mobile payments? The main objective of this report is to present primary data collected during the research through interviews with contacted companies.

    The collected primary data is classified and organised using the STOF (Service, Technology, Organisation, and Finance) model. Evidence is presented in tables. This primary data is further used for explanatory study. At the same time, this data can be used by other researchers studying the same area. The collected data is reach in facts and presents the overview of different strategies. 

  • 6607.
    Apanasevic, Tatjana
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    The Effect of Innovation on Business Networks2014Conference paper (Refereed)
  • 6608.
    Apanasevic, Tatjana
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Arvidsson, Niklas
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Sustainability and Industrial Dynamics.
    Markendahl, Jan
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Mobile payments: a proposal for a context-oriented approach based on socio-technical system theoryIn: Journal of Innovation Management, ISSN 2183-0606Article in journal (Refereed)
    Abstract [en]

    A recent review on mobile payment research by Dahlberg et al. (2015) concludes that there is a need to synthesise this research area by studying contexts in which innovation is done as well as to integrate different aspects of research. This article aims to provide a proposal for how to achieve such integration and context-orientation by building on previous studies as well as an additional review. Our systematic literature review of mobile payments research is focused on papers published during 2006–2016. The main objective is to examine how mobile payments research has been conducted from the methodological and theoretical perspectives. Our findings show that research on mobile payments is a multidisciplinary research. Three main themes, which are in line with previous studies, in research are: customer adoption, technological aspects, and business aspects. Moreover, research is mainly analytical based on deductive approach. To meet the challenge formulated in the previous research, we propose and apply a socio-technical system framework to achieve synthesis and context-specific consideration in future research on mobile payments.

  • 6609.
    Apanasevic, Tatjana
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Markendahl, Jan
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Mobile ticketing services in the Northern Europe: Critical business model issues2018In: Internet of Things Business Models, Users, and Networks, 2017 / [ed] Morten Falch, Copenhagen, Denmark: IEEE, 2018, p. 1-8Conference paper (Refereed)
    Abstract [en]

    Started as SMS ticketing, today, mobile ticketing services become a platform for combined mobility solutions that integrate mobile ticketing, bike renting, car sharing, and parking payment services. Mobile ticketing services provide a number of benefits for public transport companies and passengers, however, in some Northern European countries, the share of mobile ticket sales does not exceed 10 percent. In this paper, we analyse business models of three types of mobile ticketing services (SMS, in-app, and “Be-In Be-Out” (BIBO)) in order to identify factors that negatively affect wider penetration of mobile ticketing. In order to do so, we use STOF (Service, Technology, Organisation, and Finance) model. The research reveals that there are a number of challenges related to service, technology, and finance domains of mobile ticketing. Due to this, with the help of price policy, many public transport companies push choices of their customers towards use of plastic travel card.

  • 6610.
    Apanasevic, Tatjana
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Markendahl, Jan
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Mobile ticketing services in the Northern Europe Critical business model issues2017In: 2017 JOINT 13TH CTTE AND 10TH CMI CONFERENCE ON INTERNET OF THINGS - BUSINESS MODELS, USERS, AND NETWORKS / [ed] Falch, M, IEEE , 2017Conference paper (Refereed)
    Abstract [en]

    Started as SMS ticketing, today, mobile ticketing services become a platform for combined mobility solutions that integrate mobile ticketing, bike renting, car sharing, and parking payment services. Mobile ticketing services provide a number of benefits for public transport companies and passengers, however, in some Northern European countries, the share of mobile ticket sales does not exceed 10 percent. In this paper, we analyse business models of three types of mobile ticketing services (SMS, in-app, and "Be-InBe-Out" (BIBO)) in order to identify factors that negatively affect wider penetration of mobile ticketing. In order to do so, we use STOF (Service, Technology, Organisation, and Finance) model. The research reveals that there are a number of challenges related to service, technology, and finance domains of mobile ticketing. Due to this, with the help of price policy, many public transport companies push choices of their customers towards use of plastic travel card.

  • 6611.
    Apanasevic, Tatjana
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Stakeholder’s expectations: Mobile payments in retail in Sweden2014In: 13th International Conference on Mobile Business, 2014 (ICMB 2014), London, June 4-5, 2014, 2014Conference paper (Refereed)
    Abstract [en]

    One of the main application areas of mobile payment services in Sweden is retailing. The main stakeholders involved in this service are mobile payment service providers, banks, merchants, and consumers. The main focus of this paper is on the change of expectations of different stakeholders taking part in service provisioning. Analysis has been performed by comparison of the initial expectations before the introduction of a mobile payment service and expectations after practical experience of the service usage. Three cases of mobile payment solutions for retailing have been investigated: BART provided by Swedbank, SEQR provided by Seamless, and a service provided by Payair.

    The analysis indicates that a number of expectations of stakeholders about mobile payment services did not come true. The results for the different cases differ but the main findings are: banks were excluded from direct service provisioning; merchants see some advantaged to deploy mobile payment, but are uncertain which solution will be a dominant in the market; consumer expectations of improved purchasing experience and usefulness are not met. The performed analysis also helps to identify some of the reasons that can be seen as obstacles for a wider penetration of mobile payment services.

  • 6612.
    Apanasevic, Tatjana
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    The mobile payment in retail: Teaching case summary2013In: The 29th Annual IMP Conference (IMP2013) proceedings: Building and Managing Relationships in a Global Network: Challenges and Necessary Capabilities / [ed] Minna Rollins and Brian Rutherford, IMP Group, 2013Conference paper (Refereed)
    Abstract [en]

    The case is written for master level students from business, commerce, and technical areas having some background in strategic marketing and management. The work over case implies a group work and a discussion of a strategy behind taken decision.

    THE OBJECTIVES OF THE CASE

    The main objective of the case is to gain practical skills in and better understanding of decision making in the circumstances of market uncertainty. The decision making process requires analysis of company’s core competences (Collis and Montgomery, 2008), market forces (Porter, 1996; Porter, 2008), and understanding of consumer needs. Students should apply different analysis frameworks in order to develop a strategy improving company’s competitive advantage and leveraging opportunities provided by a new technology, namely a new mobile payment solution. In addition, a consumer-centered thinking should lead to a suggestion of a bundle of attractive added values services build on top of mobile payment solution.

  • 6613.
    Apanasevic, Tatjana
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS.
    Markendahl, Jan
    KTH, School of Electrical Engineering and Computer Science (EECS), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    The value of mobile ticketing from a public transport perspective2018In: Journal of Payments Strategy & Systems, Vol. 11, no 4, p. 292-305Article in journal (Refereed)
    Abstract [en]

    Within the field of mobile payments, the market segment for mobile ticketing services is expected to grow, driven by the public transport sector. Although a large number of studies have explored the value of mobile payments to customers (ie service end users), there is a lack of research exploring the value of mobile payment and mobile ticketing for business customers (ie transport companies and retailers). This paper aims to address this gap and to explore the kinds of value that mobile ticketing services create for public transport companies. The research considers mobile ticketing services in six Northern European countries. The research findings suggest that within the business-to-business context, mobile ticketing services create multiple dimensions of value, namely enhanced technical functionality; financial value; better working environment; operational value; and reputational and customer relationship value. For passengers, meanwhile, value takes the form of convenience and service enhancement. These benefits are factors driving adoption of mobile ticketing and mobile payment services by public transport companies.

  • 6614.
    Apanasevic, Tatjana
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Arvidsson, Niklas
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Entrepreneurship and innovation.
    An exploratory study of consumer attitudes towards mobile ticketing in Sweden2013In: 24th European Regional Conference of the International Telecommunications Society: Technology, Investment and Uncertainty, ITS , 2013Conference paper (Refereed)
    Abstract [en]

    Swedish public transport organizations have set an objective to double usage of the public transport during the next coming five years. This study attempts to investigate if the current ticket solutions support the goal of the public transport companies, and if the available mobile phone solutions can lower barriers for consumers. In order to do that, critical travelling moments for users of different market segments were estimated during a pre-study stage. The following focus group discussions helped to validate problems identified during the pre-study. At the same time, focus groups provided deeper consumer insights on general consumer perception of the transport service, ticketing, mobile payment, quality of service, consumer expectations related to the public transport services, and consumer satisfaction and loyalty.

    The conducted research helped to identify problems existing in public transport ticketing and mobile payment areas, which have the negative impact on the usage of the public transport service and contribute with additional barriers for users. Moreover, this conclusion is supported by multiple examples that clearly illustrate what does not work, and why it does not work. Hence, mentioned solutions do not support the overall objective of the public transport operators. The comprehension of these problems and barriers can contribute to a better understanding of consumer needs and expectations, and help the public transport service providers to improve the service.

  • 6615.
    Apanasevic, Tatjana
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Arvidsson, Niklas
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.).
    Stakeholders' expectations of mobile payment in retail: lessons from Sweden2016In: International Journal of Bank Marketing, ISSN 0265-2323, E-ISSN 1758-5937, Vol. 34, no 1, p. 37-61Article in journal (Refereed)
    Abstract [en]

    Purpose– The purpose of this paper is to explore the reasons behind the slow adoption of mobile payment services. The expectations of the main groups of stakeholders – the mobile service providers, the retailers, and the consumers – of the service in the retail industry in Sweden are examined. Design/methodology/approach– The authors use a qualitative case study of stakeholders’ expectations. The conceptual research framework is based on the theory of diffusion of innovations, the technology adoption model, and network externalities. The proposed framework was tested and validated by empirical findings. Findings– One of the key findings of the research highlights that acceptance of a mobile payment service depends on the ability of mobile payment providers to build networks of both retailers and consumers simultaneously. The service will attract these stakeholders if it meets their expectations in the best possible way. Another finding is that mobile payment services do not meet expectations on an enhanced purchasing process. This is the area for future service improvement. Research limitations/implications– The main limitation of this study is that only a few retailers were contacted. Practical implications– First of all, criteria from the developed research framework can be used as a guide for mobile payment service development. Second, when developing and providing a mobile payment service, mobile payment providers need to have a good understanding of the needs and expectations of retailers and consumers. Originality/value– Stakeholders’ expectations have not been a focus for research in previous studies. This is a new research object.

  • 6616.
    Apanasevic, Tatjana
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Arvidsson, Niklas
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Entrepreneurship and innovation.
    Stakeholders’ Expectations of Mobile Payment in Retail: Lessons from SwedenManuscript (preprint) (Other academic)
  • 6617.
    Apanasevic, Tatjana
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Arvidsson, Niklas
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Entrepreneurship and innovation.
    Stakeholder’s expectations: The case of mobile public transport ticketing in Sweden2014In: 13th International Conference on Mobile Business, 2014 (ICMB 2014), London, June 4-5, 2014, 2014Conference paper (Refereed)
    Abstract [en]

    One of the main areas of mobile payment application in Sweden is mobile public transport ticketing. The main stakeholders involved in this service are mobile network operators, mobile payment service providers, SMS ticket’s “technology solution” providers, public transport companies, and consumers.

    Traditionally, mobile operators have had a strong position in this niche since the mobile phone bill or pre-paid subscriptions were used for end-user billing. Due to financial regulation, this situation was changed in February 2013 when new SMS payment solutions were introduced for all public transport companies in Sweden. A number of new actors entered the scene, and the position of existing actors changed dramatically. At the same time, the Swedish mobile operators formed a joint venture, 4T Sweden, offering a new mobile payment solution – WyWallet.

    The main focus of this paper is on the change of expectations of different stakeholders taking part in provisioning of SMS payment services. Analysis has been performed by comparison of the initial expectations before the introduction of the new SMS payment system and the real outcome in approximately half a year time. Analysis revealed the fact that expectations of a number of stakeholders about mobile payment services did not come true. Moreover, due to barriers set by the mobile payment solution, mobile payment transactions in public transportation is dramatically lower than what SMS payments were before the market changed.

  • 6618.
    Aparicio, Francisco
    et al.
    Consejo Superior de Investigaciones Científicas (Spain).
    Holgado, Miguel
    Univ. Politécnica de Madrid.
    Blaszczyk-Lezak, Iwona
    Instituto de Ciencia de Materiales de Sevilla.
    Borras, Ana
    Instituto de Ciencia de Materiales de Sevilla.
    Griol, Amadeu
    Univ. Politécnica de Valencia.
    Barrios, Carlos Angulo
    Univ. Politécnica de Valencia.
    Sohlström, Hans
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Gonzalez-Elipe, Agustí­n R.
    Instituto de Ciencia de Materiales de Sevilla.
    Barranco, Angel
    Incorporation of luminescent nanometric films in photonic crystals and devices for the development of photonic sensors2010Conference paper (Refereed)
    Abstract [en]

    Dye molecules embedded in different matrices in the form of thin films are the basis of specific materials used for laser cavities, optical filters, optical gas sensors, etc. In the present communication we discuss a new methodology based on the remote microwave plasma assisted deposition of dye containing thin films that circumvent the above mentioned problems. It permits a tailored synthesis of optically active nanometric thin films containing dye molecules which are active as fluorescence emitters (i.e., coloured and fluorescent films). The principle of this new procedure is the partial polymerization of dye molecules that are evaporated over a substrate while exposed to a remote microwave Ar plasma. As a result of this process a polymeric thin film is produced in one step where some dye molecules keep intact their optical activity (although eventually, their optical response can be slightly modified by matrix effects). This methodology has been recently used for the deposition of novel plasma nanocomposites containing non-aggregated laser dyes to maximize the fluorescent emission of the materials and for the fabrication of optical NO2 sensing nanocomposites. To illustrate the possibilities of the technique we present here results for different fluorescent dye molecules, as perylene dyes, and several xanthene and oxazine derivative cationic dyes which are typically used as gain media in tuneable laser dyes. The luminescent, optical and sensing properties of these dye containing nanocomposites will be presented. These active optical layers are being developed for the fabrication of photonic sensor devices, optical filters and photonic chips (PHODYE EU Project). This is due to the full compatibility of the synthetic methodology with the present integrated microelectronic and optoelectronic technology. The possibilities for the fabrication of photonic devices integrating these active optical layers will be demonstrated. Especial attention will be paid to recent results about the incorporation of the luminescent films in photonic crystals and about the conformal growth of luminescent planar defects within artificial opals.

  • 6619. Aparicio, Francisco J.
    et al.
    Alcaire, Maria
    Gonzalez-Elipe, Agustin R.
    Barranco, Angel
    Holgado, Miguel
    Casquel, Rafael
    Sanza, Francisco J.
    Griol, Amadeu
    Bernier, Damien
    Dortu, Fabian
    Caceres, Santiago
    Antelius, Mikael
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems. APR Technol AB, Sweden.
    Lapisa, Martin
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems. Bosch Automot Elect, Germany.
    Sohlstrom, Hans
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Niklaus, Frank
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Dye-based photonic sensing systems2016In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 228, p. 649-657Article in journal (Refereed)
    Abstract [en]

    We report on dye-based photonic sensing systems which are fabricated and packaged at wafer scale. For the first time luminescent organic nanocomposite thin-films deposited by plasma technology are integrated in photonic sensing systems as active sensing elements. The realized dye-based photonic sensors include an environmental NO2 sensor and a sunlight ultraviolet light (UV) A+B sensor. The luminescent signal from the nanocomposite thin-films responds to changes in the environment and is selectively filtered by a photonic structure consisting of a Fabry-Perot cavity. The sensors are fabricated and packaged at wafer-scale, which makes the technology viable for volume manufacturing. Prototype photonic sensor systems have been tested in real-world scenarios. (C) 2016 Elsevier B.V. All rights reserved.

  • 6620. Aparicio, Francisco J.
    et al.
    Holgado, Miguel
    Borras, Ana
    Blaszczyk-Lezak, Iwona
    Griol, Amadeu
    Barrios, Carlos A.
    Casquel, Rafael
    Sanza, Francisco J.
    Sohlström, Hans
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Antelius, Mikael
    KTH, School of Electrical Engineering (EES), Microsystem Technology.
    Gonzalez-Elipe, Agustin R.
    Barranco, Angel
    Transparent Nanometric Organic Luminescent Films as UV-Active Components in Photonic Structures2011In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 23, no 6, p. 761-765Article in journal (Refereed)
    Abstract [en]

    A new kind of visible-blind organic thin-film material, consisting of a polymeric matrix with a high concentration of embedded 3-hydroxyflavone (3HF) dye molecules, that absorbs UV light and emits green light is presented. The thin films can be grown on sensitive substrates, including flexible polymers and paper. Their suitability as photonic active components in photonic devices is demonstrated.

  • 6621. Aparicio Pardo, Ramon
    et al.
    Garcia Manrubia, Belen
    Pavon Marino, Pablo
    Skorin-Kapov, Nina
    Furdek, Marija
    Balancing CapEx reduction and network stability with stable routing-virtual topology capacity adjustment (SR-VTCA)2013In: Optical Switching and Networkning Journal, ISSN 1573-4277, E-ISSN 1872-9770, Vol. 10, no 4, p. 343-353Article in journal (Refereed)
    Abstract [en]

    This paper investigates the merits of the SR–VTCA (stable routing–virtual topology capacity adjustment) approach as a mechanism to find a beneficial trade-off between network stability and reduction in capital expenditures (CapEx). These are two main objectives for the entities that own the optical infrastructure, such as network operators (NOs), and those also acting as Internet service providers (ISPs). The SR–VTCA scheme is a novel approach to adapt transparent optical networks to time-varying traffic by adjusting the number of lightpaths between node pairs, while keeping the IP routing unchanged. Lightpath bundling (LB) and anycast (AS) switching are combined in SR–VTCA operation to advertise lightpath additions/removals to the IP layer as mere adjustments (increments or decrements) in the capacity, allowing to keep the IP routing stable, and thus, simplifying control plane operations. On the contrary, a fully-reconfigurable (FR) network design, where IP routing can be also modified, would increase the burden in the control plane, but at a higher CapEx reduction, since the optical infrastructure is used more efficiently. In this work, we investigate the CapEx overprovision introduced by SR–VTCA with respect to a FR scheme. In order to do this, SR–VTCA planning problem is first modeled as a MILP formulation. A heuristic procedure based on traffic domination is then proposed to solve large instances of the problem. Exhaustive experiments are conducted comparing the SR–VTCA solutions obtained by the aforementioned MILP and heuristic proposal with solutions found by other optimization methods presented in the literature to solve the FR planning problem. Finally, the results show that SR–VTCA can achieve similar results to the FR case in terms of CapEx reduction, while a huge number of IP reroutings are saved by maintaining IP stability. Thus, SR–VTCA provides an advantageous balance between CapEx overprovisioning and the control plane overhead associated with IP rerouting.

  • 6622.
    Apazidis, Nicholas
    KTH, Superseded Departments, Mechanics.
    Focusing of strong shocks in an elliptic cavity2003In: Shock Waves, ISSN 0938-1287, E-ISSN 1432-2153, Vol. 13, no 2, p. 91-101Article in journal (Refereed)
    Abstract [en]

    Focusing of strong shock waves in a gas-filled thin chamber with an elliptic boundary is investigated theoretically and numerically. The process of reflection and convergence of cylindrical shocks generated at one of the focal points of the chamber is studied by means of Whitham's theory of geometrical shock dynamics (1957, 1959). The current calculations are based on the modified version of this theory, which takes into account the non-homogeneous flow ahead of the advancing shock, Apazidis and Lesser (1996). There are two main results of the present study indicating a qualitatively different behavior of strong shocks as compared to the linear acoustic case. (1) - the form of the reflected shock is not cylindrical and (2) - the reflected, converging shock does not focus at the geometrical second focal point of the chamber. The dependence of the form of the reflected shock and the location of its focusing point on the strength of the shock and the eccentricity of the chamber is investigated.

  • 6623.
    Apazidis, Nicholas
    KTH, School of Engineering Sciences (SCI), Mechanics.
    Numerical investigation of shock induced bubble collapse in water2016In: Physics of fluids, ISSN 1070-6631, E-ISSN 1089-7666, Vol. 28, no 4, article id 046101Article in journal (Refereed)
    Abstract [en]

    A semi-conservative, stable, interphase-capturing numerical scheme for shock propagation in heterogeneous systems is applied to the problem of shock propagation in liquid-gas systems. The scheme is based on the volume-fraction formulation of the equations of motion for liquid and gas phases with separate equations of state. The semi-conservative formulation of the governing equations ensures the absence of spurious pressure oscillations at the material interphases between liquid and gas. Interaction of a planar shock in water with a single spherical bubble as well as twin adjacent bubbles is investigated. Several stages of the interaction process are considered, including focusing of the transmitted shock within the deformed bubble, creation of a water-hammer shock as well as generation of high-speed liquid jet in the later stages of the process.

  • 6624.
    Apazidis, Nicholas
    KTH, School of Engineering Sciences (SCI), Mechanics.
    Report on the 20th international shock interaction symposium2012In: Shock Waves, ISSN 0938-1287, E-ISSN 1432-2153, Vol. 22, no 6, p. 653-Article in journal (Other academic)
  • 6625.
    Apazidis, Nicholas
    et al.
    KTH, School of Engineering Sciences (SCI), Mechanics.
    Kjellander, Malte
    KTH, School of Engineering Sciences (SCI), Mechanics.
    Tillmark, Nils
    KTH, School of Engineering Sciences (SCI), Mechanics.
    High energy concentration by symmetric shock focusing2013In: Shock Waves, ISSN 0938-1287, E-ISSN 1432-2153, Vol. 23, no 4, p. 361-368Article in journal (Refereed)
    Abstract [en]

    High-energy concentrations in gas are achieved experimentally in a specially constructed shock tube facility at KTH Mechanics. The high-energy concentration is manifested by a formation of a hot, light-emitting gas core. Experimental, numerical and theoretical investigations show that the shape of the imploding shock is of pivotal importance for the final energy concentration. Cylindrical shocks are unstable. Symmetric polygonal shocks are shown to be dynamically stable and are produced by various methods, e.g. thin wing profiles placed radially in the test section. Such symmetric polygonal shocks are able to produce extremely high energy levels at the focal point. Spectral data from 60 nanosecond short intervals of 8 microsecond light pulse give temperatures in the range of 6,000 K.

  • 6626.
    Apazidis, Nicholas
    et al.
    KTH, Superseded Departments, Mechanics.
    Lesser, M. B.
    Tillmark, Nils
    KTH, Superseded Departments, Mechanics.
    Johansson, Börje
    KTH, Superseded Departments, Materials Science and Engineering.
    An experimental and theoretical study of converging polygonal shock waves2002In: Shock Waves, ISSN 0938-1287, E-ISSN 1432-2153, Vol. 12, no 1, p. 39-58Article in journal (Refereed)
    Abstract [en]

    An experimental investigation was carried out to explore the possibility of producing converging polygonal shocks in an essentially two-dimensional cavity. Previous calculations by Apazidis and Lesser (1996) suggested that such configurations could be produced by reflecting a cylindrical outgoing shock from a smoothly altered circular boundary, the alteration having n-gonal symmetry. In the experiments the outgoing shock was produced by a spark discharge which yielded shocks in the Mach number range from 1.1 to 1.7 at a radius just prior to the reflection. Polygonal shocks were observed as predicted by using a modified form of geometrical shock dynamics, derived in the above paper. In addition, the modified theory was used to calculate the results of an experiment carried out by Sturtevant and Kulkarny (1976). The results of the numerical calculations were found to be in substantial agreement with both experiments, suggesting that the modifications in geometrical shock dynamics for non-uniform flow ahead of an advancing shock are useful in the case of shock focusing. The experiment. also showed that the polygonal shapes were stable in the examined range of shock Mach numbers. a result that may be of importance for a number of practical situations in which shock focusing is present.

  • 6627.
    Apelkrans, Mats
    et al.
    Dept of Informatics, Jönköping International Business School.
    Håkansson, Anne
    Department of Computer and Systems Sciences, Stockholm University.
    Applying Multi-Agent System Technique to Production Planning in Order to Automate Decisions2009In: AGENT AND MULTI-AGENT SYSTEMS: TECHNOLOGIES AND APPLICATIONS, PROCEEDINGS / [ed] Anne Håkansson, Ngoc Thanh Nguyen, Ronald L. Hartung, Robert J. Howlett, Lakhmi C. Jain, Springer Berlin/Heidelberg, 2009, p. 193-202Conference paper (Refereed)
    Abstract [en]

    Coordinate and deliver information is vital for the financial and operational success of a company. The information is used for understanding and evaluating performance of a manufacturing company and making decisions based on incoming information. Information about orders but also parts to be purchased, assembled for the final product to be delivered, can streamline the production line to provide good quality products in the right time and to right costs at highest profit. For profit, costs are Cut by reducing storage and searching for lowest price from established suppliers and providers on web as well as handling production planning automatically. To increase profit, we apply a multi-agent technique to production planning, which can automate business decision-making for the production line. The agents handle incoming orders, the production line, and search for information about the products at the intranet and the extranet. The outcome is decisions about the production line. The multi-agent solution becomes a complement to the production planning brought about by the company's enterprise resource planning system.

  • 6628.
    Apelkrans, Mats
    et al.
    Dept of Informatics, Jönköping International Business School.
    Håkansson, Anne
    Uppsala University, Sweden.
    Enterprise systems Configuration as an Information Logistics Process - A Case Study2007In: Proceedings of 9th International Conference on Enterprise Information Systems: ICEIS-2007 / [ed] Jorge Cardoso, José Cordeiro, Joaquim Filipe, SciTePress, 2007, Vol. 3, p. 212-220Conference paper (Refereed)
    Abstract [en]

    In this paper, we suggest using rule-based descriptions of customer’s requirements for Enterprise Systems implementing Information Logistics. The rules are developed from the users’ requirements and inserted as schedules to the Enterprise System. The output, from testing these rules, is a list of modules and parameter settings to configure the system. By using rules, we can, at least partly, automate the configuration process by traversing the several modules and thousands parameters that are in an Enterprise System. From the list, we can select the modules and the parameters that meet the customer’s requirements. Then these selected modules and parameters are visually presented through a kind of Unified Modeling Language diagrams, to support the user investigation and then to configure the system either manually or automatically. Every attempt to match a customer’s requirement to the contents of the knowledge base within the Enterprise system can be thought of as an Information Logis tics Process. The output from such a process must be examined by the user, which can give rise to a new call to the Information Logistics process. In other words the configuration work is done through a dialogue between the customer and the knowledge base of the Enterprise system.

  • 6629.
    Apelkrans, Mats
    et al.
    Dept of Informatics, Jönköping International Business School.
    Håkansson, Anne
    Uppsala University, Sweden.
    Information Coordination Using Meta-agents in Information Logistics Processes2008In: Proceedings of Knowledge-Based and Intelligent Information & Engineering Systems: KES2008 / [ed] Ignac Lovrek, Robert J. Howlett, Lakhmi C. Jain, Berlin Heidelberg: Springer Berlin/Heidelberg, 2008, p. 788-798Conference paper (Refereed)
    Abstract [en]

    In order to coordinate and deliver information in the right time and to the right place, theories from multi-agent systems and information logistics are combined. We use agents to support supply chain by searching for company specific information. Hence, there are a vast number of agents working at the Internet, simultaneously, which requires supervising agents. In this paper, we suggest using meta-agents to control the behaviour of a number of intelligent agents, where the meta-agents are working with coordination of the communication that takes place in a supply chain system. As an example, we look at a manufacturing company receiving orders on items from customers, which need to be produced. The handling of this distributed information flow can be thought of as an Information Logistics Processes and the similarities of the functioning of processes and intelligent agents’ behaviour are illuminated.

  • 6630.
    Apelkrans, Mats
    et al.
    Dept of Informatics, Jönköping International Business School.
    Håkansson, Anne
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture (Closed 20120101), Software and Computer Systems, SCS (Closed 20120101).
    Visual knowledge modeling of an Information Logistics Process: A case study2005In: Intellectual Capital, Knowledge Management and Organisational Learning: ICICKM 2005 / [ed] Dan Remenyi, Reading, UK: ACPI , 2005Conference paper (Refereed)
  • 6631. Apellaniz-Ruiz, Maria
    et al.
    Sanchez-Barroso, Lara
    Gutierrez-Gutierrez, Gerardo
    Sereno, Maria
    Garcia-Donas, Jesus
    Avall-Lundqvist, Elisabeth
    Green, Henrik
    KTH, School of Biotechnology (BIO), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Brosen, Kim
    Bergmann, Troels K.
    Rodriguez-Antona, Cristina
    Replication of Genetic Polymorphisms Reported to Be Associated with Taxane-Related Sensory Neuropathy in Patients with Early Breast Cancer Treated with Paclitaxel-Letter2015In: Clinical Cancer Research, ISSN 1078-0432, E-ISSN 1557-3265, Vol. 21, no 13, p. 3092-3093Article in journal (Refereed)
  • 6632.
    Apelmo, Elisabet
    et al.
    KTH, School of Computer Science and Communication (CSC), Centres, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC. Lund University.
    Greger, Henriksson
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies (moved 20130630). KTH, School of Computer Science and Communication (CSC), Centres, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Kan stadsbors användning av IT bidra till ett hållbart samhälle?: En kunskapsöversikt.2014Report (Other academic)
    Abstract [en]

    This report deals with everyday habits with environmental impacts in relation to the use of information and communication technology (ICT, colloquially referred to as IT).

    We raise issues related to a) how environmentally promising and problematic ‘ICT-practices’ in urban everyday life can be identified and b) how the potential for such practices to be transformed through the use of ICT can be assessed, and ultimately utilized, in the context of sustainable urban development.

    These issues we have addressed through reviewing case studies, reports etc. Case study examples showed how ICT is used, e.g. to streamline and inform, or to share resources, vehicles and other products.

    We discussed how it might be possible, from an environmental sociology perspective, to assess when and how ICT might serve as an enabling technology that enhances or replaces previous patterns of action. We also briefly included, and discussed, phenomena defined from more general sustainability science point of view, e.g. substitution, induction and rebound effects.

    An important starting point was that social structures both enable and limit specific patterns of action. The structures can only be said to exist, or be maintained, by people's actions and through their experience. Change occurs as a result of the dynamics between people's actions and the structures created by past actions. Social practices are constantly being reproduced, with additions of new elements, e g when ICT applications are put to new uses. Then patterns of social relations and systems might also change, for example in how we use energy, travel, consume or socialize during both work and leisure time.

    Our review indicates that the knowledge that partners of Centre for Sustainable Communications (CESC) currently have access to, is fragmented and with a bias towards certain types of sectors, and patterns of action. Environmentally promising practices are more researched than problematic ones. Furthermore, use of ICTs for e.g. commuting and monitoring household energy use is more researched than most other patterns of action involving use of ICTs. Research on e.g. leisure and entertainment in relation to the environment is very much absent from today’s body of knowledge (as it is defined and delimited in this report).

    As for how everyday practices might change towards increased environmental sustainability by the use of ICT, we have found the knowledge situation even more incomplete. This shows, however, that it is worthwhile for CESC researchers and partners to carry on searching and developing knowledge regarding this.

    Regarding what should be viewed as more promising respectively more problematic urban patterns of action, we have to some extent illuminated this by exemplifying international environmental sociological research that is useful for discussing social practices in relation to environmental impacts. We have exemplified how this can shed light on some of the case studies we found among the CESC researchers and partners. Based on environmental sociology we discussed in what ways city dwellers with high income account for the most environmentally problematic practices. Correspondingly, we discussed how inhabitants with low income – out of necessity–account for many promising practices. In relation to this we also briefly discussed how rebound effects should be seen as related to socio-economic position.

    Another kind of problematic aspect highlighted is that players responsible for introducing, trying out etc., new ICTs, seem to have a tendency to do this in own networks or among the urban middle class. This is problematic from a democratic point of view. In 2012, 1.2 million people in Sweden did very rarely, or not at all, use the internet in their homes. Detailed knowledge about this group's ICT related practices seems to be largely missing.  If representatives for these groups are not represented in environmental research there is a danger that they also become less visible in public debate of environmental and ICT issues.

    This means that different social positions imply different opportunities and constraints. What patterns of actions people take more or less part in is influenced by social structures, norms and regulations, the historical and the immediate context, but also by the individuals' previous experiences and knowledge. The understanding of how a change towards a more sustainable society could come about through use of ICT therefore requires knowledge of practices among the full socio-demographic range of city dwellers.

  • 6633.
    Apelqvist, Morgan
    KTH, School of Information and Communication Technology (ICT).
    Utvärdering av ny teknologi för utveckling av gränssnitt på toppen av SAP2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is aimed at those who have a business or/and technical interest in the development of interfaces to Enterprise Resource Planning (ERP) systems from SAP. There has been a substantial change in recent years with how we daily make use of the internet and mobile devices. We have all become accustomed to sleek, user-friendly and flexible interface. We make our banking and use social media on our smartphone. We then take for granted that we just as easily can use these interfaces in our tablet. This behavioral change has also happened among the users of interfaces to SAP ERP systems. The users take for granted that the interfaces should be as intuitive, user-friendly and can be used as easily on their smartphones and tablets as their laptops. However, the current interfaces to SAP ERP systems have limited possibilities to be used on mobile devices. Even the interfaces look and ease of use have had its limitations. SAP has recognized that users will not accept the limitations of the interfaces any longer and have therefore developed a new technology that they call SAPUI5. SAP claims that this technology solves the user’s new needs.

    On behalf Claremont AB, I have been asked to investigate whether SAPUI5 really solve the user’s

    emerging needs and to nail down the new technology. I have in the study built three different interfaces that correspond to the new key requirements of the users. With the interface I developed, I have shown that SAPUI5 is a highly competent technology. It can very well be used to develop future-proof user-friendly interfaces that can be used both on desktop and mobile devices. To research how SAPUI5 differs from the existing technologies I made a qualitative interview with two senior SAP developers using the older technologies. I used the result of the interview to compare the old with the new technologies. The comparison confirmed that SAPUI5 is a technology that solves many of the needs the older technologies have limitations with. Moreover, I came to the conclusion that if you are going to choose one of these technologies you do well to thoroughly research the needs imposed on the new interface. The different technologies solve different types of user needs and it is therefore essential to gain an understanding of what the users need to be able to perform using the new interface.

  • 6634. Aperia, Anita Chatarina
    et al.
    Akkuratov, Evgeny E
    Fontana, Jacopo Maria
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Brismar, Hjalmar
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Na+, K+-ATPase, a new class of plasma membrane receptors2016In: American Journal of Physiology - Cell Physiology, ISSN 0363-6143, E-ISSN 1522-1563, Vol. 310, no 7, p. C491-C495Article in journal (Refereed)
    Abstract [en]

    The Na(+), K(+)-ATPase (NKA) differs from most other ion transporters not only in its capacity to maintain a steep electrochemical gradient across the plasma membrane but also as a receptor for a family of cardiotonic steroids, to which ouabain belongs. Studies from many groups, performed during the last fifteen years, have demonstrated that ouabain, a member of the cardiotonic steroid family, can activate a network of signaling molecules and that NKA will also serve as a signal transducer that can provide a feed back loop between NKA and the mitochondria. This brief review summarizes the current knowledge and controversies with regard to the understanding of NKA signaling.

  • 6635. Apezetxea, I. S.
    et al.
    Perez, X.
    Casanueva, Carlos
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Alonso, A.
    New methodology for fast prediction of wheel wear evolution2017In: Vehicle System Dynamics, ISSN 0042-3114, E-ISSN 1744-5159, Vol. 55, no 7, p. 1071-1097Article in journal (Refereed)
    Abstract [en]

    In railway applications wear prediction in the wheel–rail interface is a fundamental matter in order to study problems such as wheel lifespan and the evolution of vehicle dynamic characteristic with time. However, one of the principal drawbacks of the existing methodologies for calculating the wear evolution is the computational cost. This paper proposes a new wear prediction methodology with a reduced computational cost. This methodology is based on two main steps: the first one is the substitution of the calculations over the whole network by the calculation of the contact conditions in certain characteristic point from whose result the wheel wear evolution can be inferred. The second one is the substitution of the dynamic calculation (time integration calculations) by the quasi-static calculation (the solution of the quasi-static situation of a vehicle at a certain point which is the same that neglecting the acceleration terms in the dynamic equations). These simplifications allow a significant reduction of computational cost to be obtained while maintaining an acceptable level of accuracy (error order of 5–10%). Several case studies are analysed along the paper with the objective of assessing the proposed methodology. The results obtained in the case studies allow concluding that the proposed methodology is valid for an arbitrary vehicle running through an arbitrary track layout.

  • 6636.
    Aphram, Marios
    KTH, School of Architecture and the Built Environment (ABE), Architecture.
    Dendron Research Station2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Dendron research station is, well, as the name suggests, a research station, set in a tropical rainforest. The site of the station is an extinct volcano with a collapsed caldera found in the country of Papua New Guinea (PNG). The caldera has 1 km high walls and has been isolated from the rest of the world for at least 200 000 years, leading to an isolated evolution of flora and fauna found in the caldera.

    The research station aims at aiding scientists in the field of canopy research, where the work of the scientists is mainly about cataloguing existing species and discover new such for the sake of science, seeing that the isolated evolution might have generated new species yet to be described to science.

    The research station is suspended in mid-air 45+ metres high up in the canopy layer of the rainforest. It utilizes the liana system found in the forest for suspension, and derives its building material and techniques from the vernacular architecture of the natives of PNG, where the aforementioned happens to be bamboo and the latter incorporates reciprocal weaving techniques.

  • 6637.
    APOLO NYSTRÖM, SEBASTIAN
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Applied Mechanical Engineering (KTH Södertälje).
    PETTERSSON, ANDERS
    KTH, School of Industrial Engineering and Management (ITM), Applied Mechanical Engineering (KTH Södertälje).
    Ytkarakterisering tätningsytorMed omkonstruktion av tätningskonceptför stegram2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 6638.
    Apolonia, Nuno
    KTH, School of Information and Communication Technology (ICT). Universitat Politecnica de Catalunya (UPC) Barcelona, Spain.
    On Service Optimization in Community Network Micro-Clouds2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Internet coverage in the world is still weak and local communities are required to come together and build their own network infrastructures. People collaborate for the common goal of accessing the Internet and cloud services by building Community networks (CNs).The use of Internet cloud services has grown over the last decade. Community network cloud infrastructures (i.e. micro-clouds) have been introduced to run services inside the network, without the need to consume them from the Internet. CN micro-clouds aims for not only an improved service performance, but also an entry point for an alternative to Internet cloud services in CNs. However, the adaptation of the services to be used in CN micro-clouds have their own challenges since the use of low-capacity devices and wireless connections without a central management is predominant in CNs. Further, large and irregular topology of the network, high software and hardware diversity and different service requirements in CNs, makes the CN micro-clouds a challenging environment to run local services, and to achieve service performance and quality similar to Internet cloud services. In this thesis, our main objective is the optimization of services (performance, quality) in CN micro-clouds, facilitating entrance to other services and motivating members to make use of CN micro-cloud services as an alternative to Internet services. We present an approach to handle services in CN micro-cloud environments in order to improve service performance and quality that can be approximated to Internet services, while also giving to the community motivation to use CN micro-cloud services. Furthermore, we break the problem into different levels (resource, service and middleware), propose a model that provides improvements for each level and contribute with information that helps to support the improvements (in terms of service performance and quality) in the other levels.At the resource level, we facilitate the use of community devices by utilizing virtualization techniques that isolate and manage CN micro-cloud services in order to have a multi-purpose environment that fosters services in the CN micro-cloud environment.At the service level, we build a monitoring tool tailored for CN micro-clouds that helps us to analyze service behavior and performance in CN micro-clouds. Subsequently, the information gathered enables adaptation of the services to the environment in order to improve their quality and performance under CN environments. At the middleware level, we build overlay networks as the main communication system according to the social information in order to improve paths and routes of the nodes, and improve transmission of data across the network by utilizing the relationships already established in the social network or community of practices that are related to the CNs. Therefore, service performance in CN micro-clouds can become more stable with respect to resource usage, performance and user perceived quality.

  • 6639.
    Apolonia, Nuno
    et al.
    Universitat Politecnica de Catalunya (UPC) Barcelona, Spain.
    Antaris, Stefanos
    Girdzijauskas, Šarunas
    KTH, School of Electrical Engineering and Computer Science (EECS), Software and Computer systems, SCS.
    Pallis, G.
    Dikaiakos, Marios
    SELECT: A distributed publish/subscribe notification system for online social networks2018In: Proceedings - 2018 IEEE 32nd International Parallel and Distributed Processing Symposium, IPDPS 2018, Institute of Electrical and Electronics Engineers (IEEE), 2018, p. 970-979, article id 8425250Conference paper (Refereed)
    Abstract [en]

    Publish/subscribe (pub/sub) mechanisms constitutean attractive communication paradigm in the design of large-scale notification systems for Online Social Networks (OSNs). Toaccommodate the large-scale workloads of notifications producedby OSNs, pub/sub mechanisms require thousands of serversdistributed on different data centers all over the world, incurringlarge overheads. To eliminate the pub/sub resources used, wepropose SELECT - a distributed pub/sub social notificationsystem over peer-to-peer (P2P) networks. SELECT organizesthe peers on a ring topology and provides an adaptive P2Pconnection establishment algorithm where each peer identifiesthe number of connections required, based on the social structureand user availability. This allows to propagate messages to thesocial friends of the users using a reduced number of hops.The presented algorithm is an efficient heuristic to an NP-hard problem which maps workload graphs to structured P2Poverlays inducing overall, close to theoretical, minimal number ofmessages. Experiments show that SELECT reduces the numberof relay nodes up to 89% versus the state-of-the-art pub/subnotification systems. Additionally, we demonstrate the advantageof SELECT against socially-aware P2P overlay networks andshow that the communication between two socially connectedpeers is reduced on average by at least 64% hops, while achieving100% communication availability even under high churn.

  • 6640.
    Apolonia, Nuno
    et al.
    KTH, School of Information and Communication Technology (ICT). Universitat Politecnica de Catalunya (UPC) Barcelona, Spain.
    Freitag, Felix
    Universitat Politècnica de Catalunya. Barcelona, Spain.
    Navarro, Leandro
    Universitat Politècnica de Catalunya, BarcelonaTECH, Barcelona, Spain.
    Gossip-based service monitoring platform for wireless edge cloud computing2017In: IEEE 14th International Conference on Networking, Sensing and Control (ICNSC), Calabria, Italy, 16-18 May, 2017, 2017Conference paper (Refereed)
    Abstract [en]

    Edge cloud computing proposes to support shared services, by using the infrastructure at the network's edge. An important problem is the monitoring and management of services across the edge environment. Therefore, dissemination and gathering of data is not straightforward, differing from the classic cloud infrastructure. In this paper, we consider the environment of community networks for edge cloud computing, in which the monitoring of cloud services is required. We propose a monitoring platform to collect near real-time data about the services offered in the community network using a gossip-enabled network. We analyze and apply this gossip-enabled network to perform service discovery and information sharing, enabling data dissemination among the community. We implemented our solution as a prototype and used it for collecting service monitoring data from the real operational community network cloud, as a feasible deployment of our solution. By means of emulation and simulation we analyze in different scenarios, the behavior of the gossip overlay solution, and obtain average results regarding information propagation and consistency needs, i.e. in high latency situations, data convergence occurs within minutes.

  • 6641.
    Apolonia, Nuno
    et al.
    KTH, School of Information and Communication Technology (ICT). Universitat Politecnica de Catalunya (UPC) Barcelona, Spain.
    Freitag, Felix
    Universitat Politècnica de Catalunya. Barcelona, Spain.
    Navarro, Leandro
    Universitat Politècnica de Catalunya, BarcelonaTECH, Barcelona, Spain.
    Leveraging deployment models on low-resource devices for cloud services in community networks2017In: Simulation (San Diego, Calif.), ISSN 1569-190X, E-ISSN 1878-1462, Vol. 77, p. 390-406Article in journal (Refereed)
    Abstract [en]

    Community networks are crowd-sourced IP networks that evolved into regional-scale computing platforms. This has led to adapting the cloud computing model for services that can operate and use computing resources inside a community network. The network and computing infrastructure is contributed by individuals, companies, organizations and maintained by its members. Community cloud devices are often low-capacity computing devices, such as home gateways or cabinet servers, with limited capabilities. These devices are used to install and operate specific personal or community services, but can be turned into multi-purpose execution environments applying machine or operating system (container) virtualization. However that requires addressing the problems of resource sharing in low-capacity devices, related to predictable performance and isolation. Our comparative analysis with the current infrastructure in community networks gives evidence about how devices can concurrently run multiple services, the trade offs between the number and resource requirements of services and the degradation of quality that services may suffer.

  • 6642.
    Apolonia, Nuno
    et al.
    KTH, School of Information and Communication Technology (ICT). Universitat Politecnica de Catalunya (UPC) Barcelona, Spain.
    Sedar, Roshan
    Universitat Politecnica de Catalunya, BarcelonaTECH ` Barcelona, Spain.
    Freitag, Felix
    Universitat Politècnica de Catalunya. Barcelona, Spain.
    Navarro, Leandro
    Universitat Politècnica de Catalunya, BarcelonaTECH, Barcelona, Spain.
    Leveraging Low-Power Devices for Cloud Services in Community Networks2015In: 3rd International Conference on Future Internet of Things and Cloud (FiCloud), Rome, Italy, 24-26 Aug. 2015, 2015Conference paper (Refereed)
    Abstract [en]

    Community networks are IP networks constantly being improved that evolve into large-scale computing platforms. This has resulted from the effort to adapt the cloud computing model towards services that can operate and utilize the resources inside the community network. The network and its infrastructure are contributed by individuals, companies, organizations and are maintained by the community itself. Community cloud devices are often low computing resource devices, such as home gateways, with limited capabilities. Currently, these devices are configured to run community services only. This has become a drawback for further adoption because of contributor's difficulty to also use the donated cloud device for private purposes. We apply container-based virtualization for the problem of resource sharing in low-capacity devices in order to create a multi-purpose execution environment in a single device. Thus, a single device can be configured to deliver to the user and the community a multi-purpose environment, such as personal and public, isolated from one another, while preserving the community cloud services. Our comparative analysis with the current infrastructure in community networks gives evidence that the capability of the devices to run concurrent services is maintained.

  • 6643. Apostolakis, A
    et al.
    Aslanides, E.
    -.
    Backenstoss, G.
    -.
    Bargassa, P.
    -.
    Behnke, O.
    -.
    Benelli, A.
    -.
    Bertin, V.
    -.
    Blanc, F.
    -.
    Bloch, P.
    -.
    Carlson, P.
    KTH, School of Engineering Sciences (SCI).
    Danielsson, Mats
    KTH, Superseded Departments, Physics.
    A determination of the CP violation parameter η+- from the decay of strangeness-tagged neutral kaons1999In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 458, no 4, p. 545-552Article in journal (Refereed)
    Abstract [en]

    LEAR offered unique opportunities to study the symmetries which exist between matter and antimatter. At variance with other approaches at this facility, CPLEAR was an experiment devoted to the study of CP, T and CPT symmetries in the neutral-kaon system. A variety of measurements allowed us to determine with high precision the parameters which describe the time evolution of the neutral kaons and their antiparticles, including decay amplitudes, and the related symmetry properties. Limits concerning quantum-mechanical predictions (EPR, coherence of the wave function) or the equivalence principle of general relativity have been obtained. An account of the main features of the experiment and its performances is given here, together with the results achieved.

  • 6644.
    Apostolakis, A.
    et al.
    -.
    Aslanides, E.
    -.
    Backenstoss, G.
    -.
    Bargassa, P.
    -.
    Behnke, O.
    -.
    Benelli, A.
    -.
    Bertin, V.
    -.
    Blanc, F.
    -.
    Bloch, P.
    -.
    Carlson, P.
    Danielsson, Mats
    KTH, Superseded Departments, Physics.
    Measurement of the energy dependence of the form factor f+ in K 0 e3 decay2000In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 473, no 1, p. 186-192Article in journal (Refereed)
    Abstract [en]

    Neutral-kaon decays to πeν were analysed to determine the q2 dependence of the K0e3 electroweak form factor f+. Based on 365612 events, this form factor was found to have a linear dependence on q2 with a slope λ+=0.0245±0.0012stat±0.0022syst.

  • 6645.
    Apostolakis, Panagiotis
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Voltage K+ Channel Modulation by Resin Acid Derivatives: A Computational Approach to Characterize the Molecular Determinants of Binding2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 6646.
    Apostolakis, Panagiotis
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Voltage K+ Channel Modulation by Resin Acid Derivatives: A Computational Approach to Characterize the Molecular Determinants of Binding2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 6647.
    Apostolopoulos, Nikolaos
    KTH, School of Electrical Engineering (EES), Electrical Energy Conversion.
    Design and implementation of an SPB converter for fault tolerant PMSynRel motor control2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The stacked polyphase bridges (SPB) converter topology is investigated in the presentthesis as a fault-tolerant choice for permanent-magnet synchronous reluctance (PMSyn-Rel) motor control. Integrated motor drive systems are studied as they offer great benefitsfor propulsion applications. Moreover, the importance of a modular topology, like theSPB, for an electric powertrain is discussed. The latter consists of a number of seriesconnected, 3-phase 2-level inverter submodules that supply separate sets of windings ina multi-star motor. The specifications of building a four-board SPB setup are examined,while the challenges of an active voltage balancing controller are analyzed. The designprocess is explained step-by-step and the final printed circuit boards (PCBs) are presented.Furthermore, the significance of low electromagnetic interference design for a converterthat requires high speed communication is highlighted. Finally, the prototype is testedthoroughly and the expected fault-tolerant capabilities are validated on a PMSynRel motor.

  • 6648.
    Apostolopoulou - Kalkavoura, Varvara
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Effects of Varying Sludge Quality on the Permeability of a Membrane Bioreactor2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis firstly includes a theory part describing, the conventional municipal wastewater treatment plant (WWTP) and especially the conventional activated sludge (CAS) process. As Stockholm municipality want to retrofit the current activated sludge system at Henriksdal into a membrane bioreactor (MBR), an extensive description of the MBR and its advantages and disadvantages are included.

    Fouling is considered a really important issue for the operation of an MBR since it reduces an MBR’s productivity over time. Therefore, description of the fouling mechanisms and the potential foulants is included as well as a description of the membrane cleaning procedures. Sludge composition is considered a very important parameter which contributes to membrane fouling and thus this master thesis aims to identify the effects of varying sludge quality on the membranes operation. Precipitation chemicals used for phosphorus chemical precipitation and especially ferrous sulphate which is examined in this master thesis are also affecting the sludge quality and the membranes operation.

    The report includes description of Henriksdal reningsverk and line 1 of the pilot MBR at Hammarby Sjöstadsverk where the experimental work was performed. The following chapter describes the experimental work performed in the laboratory including the determination of total suspended solids (TSS), volatile suspended solids (VSS), sludge volume index (SVI) and sludge’s filterability. The filterability was determined by performing the time to filter (TTF) method and the sludge filtration index (SFI) method. Furthermore, the samples were also examined in the optical microscope to determine their bulkiness and their filaments content. The iron content in the sludge was also measured from Eurofins Environment Testing Sweden AB.

    In the results section, the different parameters measured are illustrated in charts and they are compared to each other in order to define which factors contribute positively or negatively to the sludge’s filterability and thus affect the sludge quality and the membranes operation. The results indicate that SFI is a more reliable method for measuring filterability compared to TTF. Furthermore, the iron content in the sludge is proportional to the permeability as well as the filaments content observed during microscopy is proportional to the SFI or TTF. Finally, this master thesis includes recommendations for future research which basically include more analyses to identify the sludge biology and more samples taken for longer time periods. 

  • 6649.
    Apostolopoulou, Ioli
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment.
    Comparing two key modernist public squares among Athens and Stockholm: From similar morphological patterns to common urban experience2017Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    The urban form undergoes a constant evolution process that transforms the urban experience. As it has been stated by urban morphologists, the design and planning principles as well as emerging social-economic forces shape the built environment. During the period of modernism, cities reformed their urban cores according to the fundamental elements of modernism, aiming to address the ongoing urban growth, the traffic increase and the emerging social issues. Thus, after that period, several urban cores were transformed from old districts to new modern and prestigious business and commercial centers were the former urban experience disappeared. 

    The center of Athens as well as the center of Stockholm constitute two representative examples of how modernism transformed completely the built environment during that period. Traffic oriented solutions prevailed against the traditional urban districts in both cases. Thus, by experiencing these two cases, common patterns were identified on the urban form of these two key public spaces of the cities.

    The current study is aiming to unfold the evolution of their urban form and the processes of change that took place in each case during the same time. An extended analysis is conducted, where formal and non-formal conditions are thoroughly examined. Through the analysis of the urban form, this work is aiming to reveal whether common elements that are identified in the built environment produce same implications on the urban life of the public space and consequently common urban experience to the users, despite cultural differences. In addition, the emerging unique formal and non-formal conditions, that generate vitality in each case, are selectively extracted in the last chapter, where crucial interventions are proposed.

  • 6650.
    Apostolov, Rossen
    et al.
    KTH, School of Computer Science and Communication (CSC), Centres, Centre for High Performance Computing, PDC.
    Axner, Lilit
    KTH, School of Computer Science and Communication (CSC), Centres, Centre for High Performance Computing, PDC.
    Agren, Hans
    Ayugade, Eduard
    Duta, Mihai
    Gelpi, Jose Luis
    Gimenez, Judit
    Goni, Ramon
    Hess, Berk
    KTH, School of Engineering Sciences (SCI), Theoretical Physics, Theoretical & Computational Biophysics.
    Jamitzky, Ferdinand
    Kranzmuller, Dieter
    Labarta, Jesus
    Laure, Erwin
    KTH, School of Computer Science and Communication (CSC), Centres, Centre for High Performance Computing, PDC.
    Lindahl, Erik
    KTH, School of Engineering Sciences (SCI), Theoretical Physics, Theoretical & Computational Biophysics.
    Orozco, Modesto
    Peterson, Magnus
    Satzger, Helmut
    Trefethen, Anne
    Scalable Software Services for Life Science2011In: Proceedings of 9th HealthGrid conference, 2011Conference paper (Refereed)
    Abstract [en]

    Life Science is developing into one of the largest e- Infrastructure users in Europe, in part due to the ever-growing amount of biological data. Modern drug design typically includes both sequence bioinformatics, in silico virtual screening, and free energy calculations, e.g. of drug binding. This development will accelerate tremendously, and puts high demands on simulation software and support services. e-Infrastructure projects such as PRACE/DEISA have made important advances on hardware and scalability, but have largely been focused on theoretical scalability for large systems, while typical life science applications rather concern small-to-medium size molecules. Here, we propose to address this with by implementing new techniques for efficient small-system parallelization combined with throughput and ensemble computing to enable the life science community to exploit the largest next-generation e-Infrastructures. We will also build a new cross-disciplinary Competence Network for all of life science, to position Europe as the world-leading community for development and maintenance of this software e-Infrastructure. Specifically, we will (1) develop new hierarchical parallelization approaches explicitly based on ensemble and high-throughput computing for new multi-core and streaming/GPU architectures, and establish open software standards for data storage and exchange, (2) implement, document, and maintain such techniques in pilot European open-source codes such as the widely used GROMACS & DALTON, a new application for ensemble simulation (DISCRETE), and large-scale bioinformatics protein annotation, (3) create a Competence Centre for scalable life science software to strengthen Europe as a major software provider and to enable the community to exploit e-Infrastructures to their full extent. This Competence Network will provide training and support infrastructure, and establish a long-term framework for maintenance and optimization of life science codes.

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