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  • 3401.
    Albertsson, Ann-Christine
    et al.
    KTH, Superseded Departments, Polymer Technology.
    Varma, I. K.
    Recent developments in ring opening polymerization of lactones for biomedical applications2003In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 4, no 6, p. 1466-1486Article, review/survey (Refereed)
    Abstract [en]

    Aliphatic polyesters prepared by ring-opening polymerization of lactones are now used worldwide as bioresorbabale devices in surgery (orthopaedic devices, sutures, stents, tissue engineering, and adhesion barriers) and in pharmacology (control drug delivery). This review presents the various methods of the synthesis of polyesters and tailoring the properties by proper control of molecular weight, composition, and architecture so as to meet the stringent requirements of devices in the medical field. The effect of structure on properties and degradation has been discussed. The applications of these polymers in the biomedical field are described in detail.

  • 3402.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Varma, Indra Kumari
    Centre for Polymer Science and Engineering, Indian Institute of Technology, Dehli, India.
    Lochab, Bimlesh
    Centre for Polymer Science and Engineering, Indian Institute of Technology, Dehli, India.
    Finne Wistrand, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Kumar, Kamlesh
    Centre for Polymer Science and Engineering, Indian Institute of Technology, Dehli, India.
    Design and Syntesis of Different Types of Poly(Lactic acid)2010In: Poly(Lactic Acid): Synthesis, Structures, Properties, Processing and Applications / [ed] Rafael Auras, Loong-Tak Lim, Susan E. M. Selke, Hideto Tsuji, John Wiley & Sons, 2010, p. 43-58Chapter in book (Other academic)
  • 3403.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Voepel, Jens
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Dahlman, Olof
    Soderqvist-Lindblad, Margaretha
    Design of Renewable Hydrogel Release Systems from Fiberboard Mill Wastewater2010In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 11, no 5, p. 1406-1411Article in journal (Refereed)
    Abstract [en]

    A new route for the design of renewable hydrogels is presented. The soluble waste from masonite production was isolated, fractionized, and upgraded. The resulting hemicellulose rich fraction was alkenyl-functionalized and used in the preparation of covalently cross-linked hydrogels capable of sustained release of incorporated agents. Said hydrogels showed a Fickian diffusion-based release of incorporated bovine serum albumin. Also, a method for the coating of seeds with hydrogel was developed. The sustained release of incorporated growth retardant agents from the hydrogel coating on rape seeds was shown to enable the temporary inhibition of germination.

  • 3404.
    Albertsson, Galina
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Abatement of Chromium Emissions from Steelmaking Slags - Cr Stabilization by Phase Separation2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Chromium is an important alloying element in stainless steel but also environmentally harmful element. A number of mineralogical phases present in the slag matrix can contain chromium and lead to chromium leaching. Chromium in slag if not stabilized, could oxidize to the cancerogenic hexavalent state, and leach out if exposed to acidic and oxygen rich environment. Other environmental concerns are slag dusting and chromium escape to the atmosphere. Despite the fact that there is a certain risk of Cr-emission from slags at operating conditions, still very little is known regarding the emission of the oxides of chromium during the slag tapping. Spinel phase is known to be important for controlling the leaching properties of chromium from the slag. The objective of the present study was to get an understanding of the phase relationships and chromium partition in the chromium-containing industrial slags and synthetic slags with a view to control the chromium stabilization in spinel phase. The impact of slag basicity, heat treatment, oxygen partial pressure and Al2O3 addition, on the phase relationships and chromium partition has been determined. The experimental results were compared with the phase equilibrium calculations. It was found that the oxygen partial pressure in the gas phase had a strong impact on chromium partition. The experimental results show that the impact of the slag basicity on chromium partition at lower oxygen partial pressures was negligible in contrast to that in air. The amount of spinel phase was found to increase with increased Al2O3 content. Slow cooling of slag and soaking at low oxygen partial pressure would improve the spinel phase precipitation. This treatment will also lead to less Cr dissolved in the unstable matrix phases. Chromium oxide was found to be emitted when chromium containing slags were exposed to oxidizing atmosphere. The results indicate that chromium oxide evaporation increases with increase in temperature and oxygen partial pressure, but decreases with slag basicity and sample thickness.

  • 3405.
    Albertsson, Galina
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Micro-Modelling.
    Effect of the presence of a dispersed phase (solid particles, gas bubbles) on the viscosity of slag2009Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The viscosities of a set of silicone oils containing different size ranges of charcoal or paraffin particles as well as the viscosities of silicone oil foams were measured at room temperature in order to determine the effect of dispersed phase on the viscosity of a liquid and its effect on foaming ability. The effective viscosity of the samples increased with volume fraction of the second phase. The foaming ability was improved by the presence of the particles. The improved foaming effect was for the most part not a result of the increased viscosity. No connection between the particle size and the effective viscosity could be determined. On the other hand particle morphology and the particle size distribution had effect on the effective viscosity. The viscosity data were compared with a number of existing equations for the estimation of effective viscosity. Einstein-Roscoe equation is suitable for two-phase mixtures containing globular particles with narrow particle size distribution and low interfacial tension. New mathematical models are required for effective viscosity prediction, where the suspending phase viscosity, effect of the interfacial tension, as well as the particle morphology should be taken in consideration.

  • 3406.
    Albertsson, Galina
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Teng, Lidong
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Björkman, Bo
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Engström, Fredrik
    Effect of Low Oxygen Partial Pressure on the Chromium Partition in CaO-MgO-SiO2-Cr2O3-Al2O3 Synthetic Slag at Elevated Temperatures2013In: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 84, no 7, p. 670-679Article in journal (Refereed)
    Abstract [en]

    The objective of the present work is to get an understanding of the impact of Al2O3 addition on the phase relationships in the CaO-MgO-Al2O3-SiO2-Cr2O3 slags at low oxygen partial pressures (P-O2 = 10(-4) Pa), with a view to control the precipitation of Cr-spinel in the slag. The equilibrium phases in CaO-MgO-Al2O3-SiO2-Cr2O3 slag system in the range on 1673-1873 K have been investigated. The compositions close to the industrial slag systems were chosen. The Cr2O3 content was fixed at 6 wt% and MgO at 8 wt%. Al2O3 contents in the slag were varied in the range of 3-12 wt%. The basicity (CaO/SiO2) of slag was set to 1.6. Gas/slag equilibrium technique was adopted. The samples were heated to 1873 K and soaked at this temperature for 24 h. The samples were then slow cooled to 1673 K and equilibrated for an additional 24 h. The oxygen partial pressure was kept at 10(-4) Pa. A gas mixture of CO/CO2 was used to control the oxygen partial pressure. After the equilibration, the samples were quenched in water. The chromium distribution and phase compositions in the quenched slags were studied using SEM-WDS and XRD techniques. The results were compared with the phase equilibrium calculations obtained from FACTSAGE software and the samples equilibrated in air. The size of spinel crystals increased drastically after slow cooling followed by annealing compared to samples being quenched after soaking at 1873 K. It was also found that low oxygen partial pressure had a strong impact on chromium partition. The amount of spinel phase increases with increased Al2O3 content.

  • 3407.
    ALBERTSSON, LINNÉA
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Applied Mechanical Engineering (KTH Södertälje).
    AMBERNTSSON, DAVID
    KTH, School of Industrial Engineering and Management (ITM), Applied Mechanical Engineering (KTH Södertälje).
    Leda säkert2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 3408.
    Albertsson, Mimmi
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID.
    TILLGÄNGLIGHET PÅ SVENSKA KOMMUNERS WEBBPLATSER: En kartläggning av kommuners arbete med att göra deras webbplats tillgänglig för personer med funktionsnedsättning.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Swedish municipalities' websites contain vast amounts of information that caters to a broad audience. For users to be able to access this information, it is important that the website is accessible, to everyone. 74 percent of people with disabilities states in a survey conducted by the Swedish Agency for Participation (2015a) that they use the internet to make contact with local municipalities, but simultaneously more than 1 out of 10 experiences difficulties associated with the use of computers and the Internet, according to Statistics Sweden (2014). The purpose of this study was to identify how Swedish municipalities are working to make their website available for people with disabilities. The study also examined what municipalities should do to make available their website and what difficulties are in the process of making a municipal website available.

     

    In working with this survey people who have insights into the subject and seven community representatives were interviewed. To collect quantitative data a questionnaire survey answered by 208 of Sweden's 290 municipalities was conducted.

     

    The study resulted in a survey of how Swedish municipalities work with web accessibility, a study of what actions the municipalities should take and also problematic factors in the process to become accessible. Today, many municipalities are investing in the development of new websites but there are four main factors that affect their work. These factors are lack of knowledge, lack of resources, organizational characteristics, such as unclear division of responsibility and decentralized organizations, and the lack of distinct requirements. The survey also shows that there are significant differences between the small and big municipalities regarding their accessibility initiative.

  • 3409.
    Albertsson, Mimmi
    et al.
    KTH, School of Computer Science and Communication (CSC).
    Arningsmark, Isabella
    KTH, School of Computer Science and Communication (CSC).
    Svenska företags användning av sociala medier som marknadsföringsverktyg – En observation över vilka aktiviteter som lämpar sig att bedriva på sociala medier idag.2012Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today companies increasingly use social media as a part of their marketing strategy. Most companies have discovered the value of using social media and are today registered on multiple platforms, but what kind of content is published by the companies on these platforms? The different platforms are constructed in different ways and around different attributes; are there therefore certain types of content that are more suitable to publish on a certain platform?

    This thesis addresses and answers the following main question: What different kinds of activities are suitable for Swedish companies to conduct on different social media platforms? The question have been answered by the theory that this thesis processed, by an observation of how Swedish companies are using social media today and by interviews conducted with one company and one PR agency. Based on a discussion of the results of the thesis it appears that it is not possible to draw guidelines for what kind of posts that is more or less suitable to publish on the different platforms. What instead seems to determine which platform that the companies should use is the depth of the information they would like to publish. For all platforms it is shown that the focus of the companies should be interaction with users of the platforms. They should also publish posts frequently on the platforms they are using, but not with an excessive frequency as this tends to disturb the users.

  • 3410.
    Albertsson, Peter
    KTH, School of Information and Communication Technology (ICT).
    Entreprenörskap och programutveckling2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    At the end of 2005 a new application was developed. The new application had an innovational potential to be markets international, which later led to a patent application and the business Mobisma AB was invented. The technical solutions meet the requirements for a patent application and it got novelty, inventive and an industrial application. The intent of this invention was to guide the user from commodity status in to a telephone exchange from their cell phones. At the year end of 2005/2006 it was unique with this type of applications for a cell phone. There were plenty of telecommunications industry businesses that showed interest in the solution of their system. The business Mobisma is today silver partners with Panasonic World Wide.

    This report describes the completed development with an emphasis on entrepreneurship and patents. Two very important areas that are important for an engineer to know about of this sorts of ambitions. This history and its experiences that are described are very important to know about.

  • 3411.
    Albertsson, Ann-Christine
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Edlund, Ulrica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Wood hydrolysates: From fractions to products2015In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 249Article in journal (Other academic)
  • 3412.
    Albihn, Sara
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Ivarsson, Erica
    ÄNDRAD ANVÄNDNING AV BEFINTLIG BYGGNAD: från kontor till studentbostäder2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There is a housing shortage in Stockholm and the most vulnerable group are young people who are tryingto establish themselves on the housing market. The lack of housing opportunities is forcing students towait for many years before they get a chance to rent a home and thus contributes to withdrawal fromstudies. The establishment of new student-housing is growing but there is still much progress to bemade until the needs are fully satisfied. At the same time office spaces are left vacant with no tenantswaiting to move in. Stockholm is growing at an increasingly high pace and establishing new housing is aninescapable truth. Furthermore, tearing down existing buildings can cause a strain on the environmentwhereas preserving existing buildings can contribute with cultural value and befriend sustainability.Although the intended use of a building isn’t always suitable for its layout. In this instance, changing thepurpose can contribute to the preservation of a building and at the same time fulfil the needs originatingfrom the shortage of housing.This degree project within the Bachelor programme in Construction Engineering at the Royal Institute ofTechnology in Stockholm, has been performed at Ahlsénarkitekterna during 10 weeks. This thesis treatsthe subject of the adaptive reuse of existing office buildings into student housing.

  • 3413.
    Albini, Gabriele Luigi Aldo
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.).
    "An Analysis of the European Telecommunications Strategic Environment: How Can Strategic Actions Be Defined to Adapt to the New Scenario? A Telefónica Case Study"2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This research presents an analysis of the European Telecommunication strategic environment with particular focus on the three macro-changes which have been influencing the recent history of such industry. These are, first of all, the shift from a government-controlled market to a privatized market. Second, the introduction of price limitations - called Eurotariff - which are supposed to regulate the mobile traffic throughout Europe. Finally, the constant growth of data and internet traffic demand, compared to the voice traffic demand, mainly due to the success of OTTs (Over-the-Tops) and the introduction of NGN (Next-Generation Network) applications and software. Such changes have increased the competition in an industry which was organized in monopolies and are forcing the companies to change, following the different customers' needs. Throughout the essay, a case study about Telefónica has been developed: after a presentation of the company and of Telefónica's deregulation process, the consequences of the environment analysis will be defined and, finally, some strategic actions will be proposed in order to adapt to the new strategic environment. The methodology which has been followed consists in a research on the models existing in literature designed to analyze the strategic environment. The best ones have been used and applied to the real case, involving Telefónica: the findings obtained have then been considered the basis to define the strategic actions. The purpose of the paper is twofold: first of all to offer an understanding of the telecommunications business with a particular focus on the Eurotariff, OTTs and NGN phenomena; second to show how a strategic environment can be effectively studied, focusing on the changes that characterize the industry, and how the consequences can be deduced. The information coming from this type of studies is very important for a company to understand what to change in order to adapt to a new context and achieve better performances.

  • 3414.
    Albinski, Szymon Janusz
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Optimization and Systems Theory.
    A branch-and-cut method for the Vehicle Relocation Problem in the One-Way Car-Sharing2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to develop an algorithm which solves the Vehicle Relocation Problem in the One-Way Car-Sharing (VRLPOWCS) as fast as possible. The problem describes the task of relocating the cars to areas with the largest demand. The chauffeurs who relocate the cars are transported by shuttle buses. Each car is assigned an individual relocation utility. The objective is to find shuttle tours that maximise in a given time the relocation utility while balancing the distribution of the cars. The VRLPOWCS is formulated as a mixed integer linear program. Since this problem is NP-complete we choose the branch-and-cut method to solve it. Using additional cutting planes – which exploit the structure of the VRLPOWCS – we enhance this method. Tests on real data show that this extended algorithm can solve the VRLPOWCS faster.

  • 3415. Albinsson, A.
    et al.
    Bruzelius, F.
    Jacobson, B.
    Gustafsson, T.
    Jonasson, Mats
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering. Volvo Cars, Sweden.
    Identification of tyre characteristics using active force excitation2016In: The Dynamics of Vehicles on Roads and Tracks - Proceedings of the 24th Symposium of the International Association for Vehicle System Dynamics, IAVSD 2015, CRC Press, 2016, p. 501-510Conference paper (Refereed)
    Abstract [en]

    Knowledge of the maximum tyre-road friction coefficient can improve active safety systems by defining actuator boundaries and adaptable intervention thresholds. Estimation of the coefficient of friction based on tyre response measurements requires large level of force excitation. Under normal driving conditions, manoeuvres with large tyre utilizations are rare. This study investigates a method where wheel torques with opposite signs are applied to the front and rear axle simultaneously. This procedure allows for an intervention with large tyre excitations without disturbing the motion of the vehicle. The intervention is evaluated in simulations and experiments. Further, a method is proposed which does not require measurement of the vehicle longitudinal velocity. The results show that it is possible to estimate the current friction coefficient with the proposed method, although the assumption made in the proposed method makes the friction estimate sensitive to measurement noise on the wheel speed signal.

  • 3416. Albinsson, Anton
    et al.
    Bruzelius, Fredrik
    Pettersson, Pierre
    Jonasson, Mats
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering. Volvo Car Corporation, Sweden.
    Jacobson, Bengt
    Estimation of the inertial parameters of vehicles with electric propulsion2016In: Proceedings of the Institution of mechanical engineers. Part D, journal of automobile engineering, ISSN 0954-4070, E-ISSN 2041-2991, Vol. 230, no 9, p. 1155-1172Article in journal (Refereed)
    Abstract [en]

    More accurate information about the basic vehicle parameters can improve the dynamic control functions of a vehicle. Methods for online estimation of the mass, the rolling resistance, the aerodynamic drag coefficient, the yaw inertia and the longitudinal position of the centre of gravity of an electric hybrid vehicle is therefore proposed. The estimators use the standard vehicle sensor set and the estimate of the electric motor torque. No additional sensors are hence required and no assumptions are made regarding the tyre or the vehicle characteristics. Consequently, all information about the vehicle is available to the estimator. The estimators are evaluated using both simulations and experiments. Estimations of the mass, the rolling resistance and the aerodynamic drag coefficient are based on a recursive least-squares method with multiple forgetting factors. The mass estimate converged to within 3% of the measured vehicle mass for the test cases with sufficient excitation that were evaluated. Two methods to estimate the longitudinal position of the centre of gravity and the yaw inertia are also proposed. The first method is based on the equations of motion and was found to be sensitive to the measurement and parameter errors. The second method is based on the estimated mass and seat-belt indicators. This estimator is more robust and reduces the estimation error in comparison with that obtained by assuming static parameters. The results show that the proposed method improves the estimations of the inertial parameters. Hence, it enables online non-linear tyre force estimators and tyre-model-based tyre-road friction estimators to be used in production vehicles.

  • 3417.
    Albinsson, Sofie
    KTH, School of Biotechnology (BIO).
    Automation of manual Hepatitis E (HEV) and Hepatitis A (HAV) PCR analysis to Tecan FreedomEVO 1502017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 3418.
    Albiol Graullera, Pablo
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Architecture Design and Interoperability Analysisof a SCADA System for the Power Network Control and Management2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    SCADA (Supervisory Control and Data Acquisition) systems have been widely used during the last decades delivering excellent results for the power network operation and management. However, some current customer requirements are for SCADA systems to integrate external components in order to perform advanced power network studies and develop both existing and new business processes. This novel viewpoint will make these systems evolve from a monolithic infrastructure towards a loosely coupled and flexible architecture. Hence, new needs have arisen with the aim of improving the system interoperability, reducing the complexity and enhancing the maintainability. This master´s thesis project presents an Interoperability Prediction Framework (IPF), that supports the architecture design process during the early stages of product development. In addition, this work has also investigated some alternative architectures, which have been modelled and verified using the previously mentioned framework. A first conceptual architecture has been designed to improve the internal system interoperability, reducing the coupling between the basic SCADA and the Energy Management System (EMS). Later, a second architecture that allows the integration of external components has been introduced to promote the external interoperability. Results show that the proposed architectures are correct (according to the IPF) and the interoperability of the system is improved. Furthermore, initial conclusions suggest that the final proposed solution would be less complex than the current architecture in the long term, although a large effort and substantial changes would be needed to upgrade the system architecture.

  • 3419. Albiol, T.
    et al.
    Van Dorsselaere, J. P.
    Chaumont, B.
    Haste, T.
    Journeau, Christophe
    Meyer, Leonhard
    Sehgal, Bal Raj
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Power Safety.
    Schwinges, Bernd
    Beraha, David
    Annunziato, Alessandro
    Zeyen, Roland
    SARNET: Severe accident research network of excellence2010In: PROG NUCL ENERGY, 2010, Vol. 52, no 1, p. 2-10Conference paper (Refereed)
    Abstract [en]

    Fifty-one organisations network in SARNET (Severe Accident Research NETwork of Excellence) their research capacities in order to resolve the most important pending issues for enhancing, with regard to Severe Accidents (SA). the safety of existing and future Nuclear Power Plants (NPPs). This project. co-funded by the European Commission (EC) under the 6th Framework Programme, has been defined in order to optimise the use of the available means and to constitute sustainable research groups in the European Union. SARNET tackles the fragmentation that may exist between the different national R&D programmes, in defining common research programmes and developing common computer tools and methodologies for safety assessment. SARNET comprises most of the organisations involved in SA research in Europe, plus Canada. To reach these objectives, all the organisations networked in SARNET contributed to a joint Programme of Activities, which consisted of: Implementation of an advanced communication tool for accessing all project information, fostering exchange of information, and managing documents: Harmonization and re-orientation of the research programmes, and definition of new ones; Analysis of the experimental results provided by research programmes in order to elaborate a common understanding of relevant phenomena; Development of the ASTEC code (integral computer code used to predict the NPP behaviour during a postulated SA), which capitalizes in terms of physical models the knowledge produced within SARNET; Development of Scientific Databases in which all the results of research programmes are stored in a common format (DATANET); Development of a common methodology for Probabilistic Safety Assessment of NPPs; Development of short courses and writing a textbook on Severe Accidents for students and researchers; Promotion of personnel mobility amongst various European organisations. This paper presents the major achievements after four and a half years of operation of the network, in terms of knowledge gained, of improvement of the ASTEC reference code, of dissemination of results and of integration of the research programmes conducted by the various partners. After this first period (2004-2008), co-funded by the EC, a further contract SARNET2 with the EC for the next four years started in April 2009 as part of the 7th Framework Programme. During this period, the networking activities will focus mainly on the remaining pending issues as determined during the first period, experimental activities will be directly included in the common work and the network will evolve toward complete self-sustainability. The bases for such an evolution are presented in the last part of the paper.

  • 3420.
    Albiz, Niccolas
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Sustainability and Industrial Dynamics.
    Sustainability Education at Industrial Engineering Programs in Sweden: A study of the relevant and received sustainability education, and the associated challenges, at 5-year industrial engineering programs2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The public concern for sustainability issues is ever increasing whilst the trust in corporations is decreasing. CEOs now see sustainability concern and compliance as an important component in retaining their competitive advantage and regaining the trust of their surrounding community. For these reasons it is important to find new manners of uniting societal improvement with business, requiring new forms of competencies. This study has investigated what sustainability education is actually central to the industrial engineering profile, as well as what of this is then covered in the programs.

    The study involved two phases. The first involved interviewing experts as to what was central for these engineers to learn, resulting in a content list. The second phase involved mapping the instances of this content in the five largest industrial engineering programs (covering circa 74% of these students) as well as the associated challenges to broaching this content. The first phase was primarily qualitative whilst the second phase was largely quantitative, though each data point consisted of a qualitative interview.

    Five key insights can be drawn from the study regardless of normative stand-point. 1) The sustainability topics that were deemed relevant cover a vast area of disciplines and aspects. 2) There is a skewedness in the content covered, favouring the environmental aspects. 3) There is a lack of integrative instances where the knowledge from different sources and perspectives is synthesized. 4) The key challenges revolve around concept definition and communication. 5) The normativity, interconnectedness and pedagogics contribute with uncertainty and complexity in the assessment of sustainability education.

    The study is finalized with a synthesis of the various insights to arrive at the conclusion that having sustainable business practice as the aim of the programs, establishing common content goals and employing active learning approach would circumvent many of the perceived challenges as well as align the programs with the need of the industry.

    This study contributes with deeper understanding of the sustainability education required and provided to industrial engineering students in Sweden. As such the study has practical applications for the programs studied. The theoretical implications of this study lie in the empirical data achieved regarding the topics of relevance to these engineers, showing high levels of agreement with current literature, as well as the perceived challenges to broaching this content in the current curricula. Furthermore it provides empirical data as to the sustainability education received at different programs.

  • 3421.
    Albiz, Niccolas
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Sustainability and Industrial Dynamics.
    Sustainability Education at Industrial Engineering Programs in Sweden: A study of the relevant and received sustainability education, and the associated challenges, at 5-year industrial engineering programs2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The public concern for sustainability issues is ever increasing whilst the trust in corporations is decreasing. CEOs now see sustainability concern and compliance as an important component in retaining their competitive advantage and regaining the trust of their surrounding community. For these reasons it is important to find new manners of uniting societal improvement with business, requiring new forms of competencies. This study has investigated what sustainability education is actually central to the industrial engineering profile, as well as what of this is then covered in the programs.

    The study involved two phases. The first involved interviewing experts as to what was central for these engineers to learn, resulting in a content list. The second phase involved mapping the instances of this content in the five largest industrial engineering programs (covering circa 74% of these students) as well as the associated challenges to broaching this content. The first phase was primarily qualitative whilst the second phase was largely quantitative, though each data point consisted of a qualitative interview.

    Five key insights can be drawn from the study regardless of normative stand-point. 1) The sustainability topics that were deemed relevant cover a vast area of disciplines and aspects. 2) There is a skewedness in the content covered, favouring the environmental aspects. 3) There is a lack of integrative instances where the knowledge from different sources and perspectives is synthesized. 4) The key challenges revolve around concept definition and communication. 5) The normativity, interconnectedness and pedagogics contribute with uncertainty and complexity in the assessment of sustainability education.

    The study is finalized with a synthesis of the various insights to arrive at the conclusion that having sustainable business practice as the aim of the programs, establishing common content goals and employing active learning approach would circumvent many of the perceived challenges as well as align the programs with the need of the industry.

    This study contributes with deeper understanding of the sustainability education required and provided to industrial engineering students in Sweden. As such the study has practical applications for the programs studied. The theoretical implications of this study lie in the empirical data achieved regarding the topics of relevance to these engineers, showing high levels of agreement with current literature, as well as the perceived challenges to broaching this content in the current curricula. Furthermore it provides empirical data as to the sustainability education received at different programs. 

  • 3422.
    Albiz, Niccolas
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Nilsson, Jonatan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Feasibility Study of Heating and Cooling Solutions for Wuxi Eco-City2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Wuxi city has a strong economy and is well located for an eco city project, only 128 km from Shanghai. Wuxi Eco-City is a Sino-Swedish initiative to build an environmentally friendly district. The 2.4 km2 area will include residential buildings, commercial buildings, offices and potentially a stadium. A preliminary urban plan has been made, providing housing for 20 000 people. China has a large energy demand and heating in the northern regions is responsible for around 30% of the annual energy usage. A heating solution that is efficient, scalable, sustainable and economical needs to be developed for the eco city to not increase the burden on the system. This report investigates what heating and cooling solutions would be optimal for the eco city, basing its evaluation on the performance, implementability, scalability and risk of the different solutions. A model was constructed for visualization purposes and to create a scenario of what the overall energy usage could be given certain parameters. The GSHP technology is deemed the most appropriate solution for Wuxi Eco-City and the estimated annual energy usage for the scenario was 1822 MWh.

     

    Further economic analyses of the cases when the annual heating/cooling load is low should be made to determine if there are cases in which an ASHP or a VRV system should be preferred. An alternative suggestion is to implement a minor centralized heating and cooling system using WSHPs. Studies should be performed concerning effect on Lake Taihu, economic viability, and expected performance before an implementation.

  • 3423. Albornoz, N. L. Gonzalez
    et al.
    Schmidt-May, Angnis
    von Strauss, Mikael
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA.
    Dark matter scenarios with multiple spin-2 fields2018In: Journal of Cosmology and Astroparticle Physics, ISSN 1475-7516, E-ISSN 1475-7516, no 1, article id 014Article in journal (Refereed)
    Abstract [en]

    We study ghost-free multimetric theories for (N + 1) tensor fields with a coupling to matter and maximal global symmetry group S-N x (Z(2))(N). Their mass spectra contain a massless mode, the graviton, and N massive spin-2 modes. One of the massive modes is distinct by being the heaviest, the remaining (N - 1) massive modes are simply identical copies of each other. All relevant physics can therefore be understood from the case N = 2. Focussing on this case, we compute the full perturbative action up to cubic order and derive several features that hold to all orders in perturbation theory. The lighter massive mode does not couple to matter and neither of the massive modes decay into massless gravitons. We propose the lighter massive particle as a candidate for dark matter and investigate its phenomenology in the parameter region where the matter coupling is dominated by the massless graviton. The relic density of massive spin-2 can originate from a freeze-in mechanism or from gravitational particle production, giving rise to two different dark matter scenarios. The allowed parameter regions are very different from those in scenarios with only one massive spin-2 field and more accessible to experiments.

  • 3424.
    Albrecht, Martin
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Enabling socio-technical transitions – electric vehicles and high voltage electricity grids as focal points of low emission futures2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Today humankind is facing numerous sustainability challenges that require us to question CO2 intensive practices like those present in the transport and energy sector. To meet those challenges, many countries have adopted ambitious climate targets. Achieving such targets requires an understanding of the wider socio-technical context of transitions. The aim of this licentiate thesis is therefore to analyse such socio-technical transitions towards low-emission futures enabled by the electrification of passenger cars and high voltage grid development.

    A combination of different transitions theories (for ex. Multi-level perspective and Technological innovation systems) and institutional theory has been used. To reach the aim paper I analyses the climate impacts of electric vehicles (EVs) and policy measures to achieve a breakthrough scenario for EVs. The results show that a mixture of short and long term policies are needed that take into account the technology development stage and behavioural aspects of EV adopters. Paper II addresses the need to include the high voltage transmission grid and its planning procedures as a central part of debates on transitions. Therefore the opportunities, challenges and reasons for conflict in the established regime are studied. The results show that in order to achieve a sustainable grid development regime, it is necessary to spend time on achieving legitimacy and social sustainability. The third paper uses semi-structured expert interviews and focuses on innovation dynamics for EV adoption. By focusing on dynamics instead of single policy measures, it is possible to grasp interactions within a niche, but also in between a niche, regime and landscape. The results show that strong initial technology legitimacy was needed to start substantial innovation dynamics. This could be further strengthened with a strong and broad coalition of actors. Both those factors led, if present, to an improved variety and match of policy instruments.

    As such this thesis has shown that transitions are not just about technology or policy instruments as such but about the dynamics and processes needed to enable them. This can be relevant in other transitions that otherwise may underestimate the importance of these components.

  • 3425.
    Albrecht, Martin
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Nordic power road map 2050: Strategic choices towards carbon neutrality. D4.1.R Institutional grid review.2013Report (Other academic)
  • 3426.
    Albrecht, Martin
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    System innovation dynamics around electric vehicles. The cases of Norway, Denmark and Sweden.Manuscript (preprint) (Other academic)
    Abstract [en]

    This paper focuses on the comparison of electric car innovation patterns in Norway, Sweden and Denmark. Doing so, it takes a closer look at what the most essential dynamics in the systems were over time and what enabled those dynamics. The main research aim is to contribute to a wider understanding of why Norway is so much ahead of Sweden and Denmark in electric car adoption. The purpose is also to adopt a perspective that goes beyond a mere focus on economic policy instruments. In order to do so different theory elements are combined in a framework. These elements stem from the transition theory literature field, especially the technological innovation system (TIS) and the multi-level perspective (MLP). This combination allows analysing the development behind a dynamic, not just when it comes to an innovation itself but also with regards to the established regime. The data is gathered through analysis of existing documents and data as well as a series of 27 expert interviews conducted in the three case countries. The findings suggest that there are important differences in transition patterns that can account for the electric vehicle (EV) diffusion situation we can find nowadays in the three Nordic countries. An important stepping stone was the need for a very strong legitimacy of the original EV vision that is also anchored in a coordinated, sector overarching coalition of actors that thinks strategically and long term. Moreover some general beneficial dynamics could be identified across the countries in question. In Norway these beneficial dynamics can be summarised as a systems motor, in Denmark as a failed entrepreneurial motor that shifted towards a constrained municipal motor and in Sweden as a loosely, coordinated and weaker version of a systems motor.

  • 3427.
    Albrecht, Martin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Nilsson, Måns
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). Stockholm University, Stockholm Environment Institute.
    Åkerman, Jonas
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Electrification of vehicles – policy drivers and impacts in two scenarios.2013In: Grid Integration of Electric Vehicles in Open Electricity Markets / [ed] Qiuwei Wu, John Wiley & Sons, 2013Chapter in book (Refereed)
    Abstract [en]

    This chapter examines current policy drivers of battery electric vehicles (EVs) and plug-in hybrid EVs, the current and anticipated impacts on carbon emissions, as well as what potential role policy can play in enhancing the innovation system and market development around such vehicles in the future. We start with a policy review of key targets in the Nordic countries and the EU, up to 2030, and discuss to what extent they are consistent with industry and expert estimates of how the systems can grow. On the basis of this, the second part elaborates two simple scenarios of EV development in the EU: one breakthrough expansion scenario and one incremental expansion scenario. Building on that is an analysis of the climate impacts of the two scenarios, given different assumptions relating to, for example, electricity production as well as EV penetration in the fleet. The third part examines what policy drivers might be needed to enable the breakthrough scenario, using a technological innovation systems perspective to describe the needed processes, drivers and developments.

  • 3428.
    Albrecht, Martin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Nilsson, Måns
    Åkerman, Jonas
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Nordic power road map 2050:Strategic choices towards carbon neutrality. D4.2.R Policy and Institutional Review Electric Vehicles (EV).2012Report (Other academic)
    Abstract [en]

    This report examines policy drivers of electric vehicles (EVs), and what potential role policy can play in enhancing the innovation and market development of EVs. We start with a policy review of key targets in the Nordic countries and the EU, up to 2030, and discuss to what extent they are consistent with industry, government and expert estimates of how the EV innovation systems can grow. On the basis of this, the second part examines what policy drivers might be needed to enable a breakthrough scenario, using a technological innovation systems (TIS) perspective to describe the needed processes, drivers and developments in policy and technology.

  • 3429. Albrecht, Stefano V.
    et al.
    Beck, J. Christopher
    Buckeridge, David L.
    Botea, Adi
    Caragea, Cornelia
    Chi, Chi-hung
    Damoulas, Theodoros
    Dilkina, Bistra
    Eaton, Eric
    Fazli, Pooyan
    Ganzfried, Sam
    Giles, C. Lee
    Guillet, Sebastien
    Holte, Robert
    Hutter, Frank
    Koch, Thorsten
    Leonetti, Matteo
    Lindauer, Marius
    Machado, Marlos C.
    Malitsky, Yuri
    Marcus, Gary
    Meijer, Sebastiaan
    KTH, School of Technology and Health (STH), Health Systems Engineering.
    Rossi, Francesca
    Shaban-Nejad, Arash
    Thiebaux, Sylvie
    Veloso, Manuela
    Walsh, Toby
    Wang, Can
    Zhang, Jie
    Zheng, Yu
    Reports on the 2015 AAAI Workshop Series2015In: The AI Magazine, ISSN 0738-4602, Vol. 36, no 2, p. 90-101Article in journal (Refereed)
    Abstract [en]

    AAAI's 2015 Workshop Program was held Sunday and Monday, January 25-26, 2015, at the Hyatt Regency Austin Hotel in Austin, Texas, USA. The AAAI-15 workshop program included 16 workshops covering a wide range of topics in artificial intelligence. Most workshops were held on a single day. The titles of the workshops included Algorithm Configuration; Artificial Intelligence and Ethics; Artificial Intelligence Applied to Assistive Technologies and Smart Environments; Artificial Intelligence for Cities; Artificial Intelligence for Transportation: Advice, Inter-activity, and Actor Modeling; Beyond the Turing Test; Computational Sustainability; Computer Poker and Imperfect Information; Incentive and Trust in E-Communities; Knowledge, Skill, and Behavior Transfer in Autonomous Robots; Learning for General Competency in Video Games; Multiagent Interaction without Prior Coordination; Planning, Search, and Optimization; Scholarly Big Data: AI Perspectives, Challenges, and Ideas; Trajectory-Based Behaviour Analytics; and World Wide Web and Public Health Intelligence.

  • 3430.
    Albrecht, Steffen
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Sigma-delta based techniques for future multi-standard wireless radios2005Doctoral thesis, monograph (Other scientific)
    Abstract [en]

    Improvements in process technology and design innovations have resulted in compact and cost effective digital baseband solutions. The radio part, however, has remained a bottleneck in terms of chip area and power consumption as the feature size of analog devices does not directly benefit from scaling. With the addition of yet more standards into emerging products, the requirements of future radios will extend over characteristic performance features into demands of programmable and reconfigurable hardware for radios covering multiple frequency bands. Hence, a guideline in the design of such radios is a large degree of hardware sharing.

    The thesis investigates the application of sigma-delta modulation to arising multistandard wireless radios. First, it reviews principles in wireless radios, such as selected modulation and access techniques. It also examines several communication standards of personal wireless radios as well as common receiver architectures for their implementation. This is followed by general considerations and background information about sigma-delta modulators. In the third and fourth chapter, implementations to two blocks of a wireless radio receiver system are suggested: An architecture for a frequency synthesizer and an implementation of an analog-to-digital converter.

    In the first contribution, the thesis develops a novel concept for frequency synthesis that is more suitable for multi-band, multi-standard radio architectures, achieving a large amount of hardware sharing among different wireless standards. As a second pillar, the thesis contributes with the design of a dual-standard sigma-delta modulator for data conversion within a radio receiver. Parts of the work concerning the dual-standard modulator are embodied in a granted swedish patent.

  • 3431.
    Albrecht, Tomás
    KTH, School of Electrical Engineering and Computer Science (EECS), Media Technology and Interaction Design, MID.
    Designing the Publikvitto, a system to make government expenditure tangible2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Air transportation is essential to our society. It enables global trading, brings people together, and lets travelers explore distant parts of the world. However, flying is a highly unsustainable behavior and accounts for roughly 2% of all carbon emissions; with industry and research forecasting constant growth in the coming years. The economic benefits rhetoric often prevails over the environmental costs, though; motivating governments to give incentives to airports and airlines. The Swedish Government, despite its green goals and pro-sustainability actions, is no exception, and both municipal and federal funds support the air route network.

    This thesis reports on the development of the Publikvitto, a system designed to help citizen make sense of the government's incentives to the flying industry. The process is based on research through design and inspired by reflective practices. The primary outcome are insights into the relationship between designer, social issues, and government's actions; and how these elements can be approached in order to design artifacts that motivate people to engage in political discussions.

  • 3432.
    Al-Breihi, Mohammed
    KTH, School of Technology and Health (STH).
    Utveckling av laboration om trefastransformatorn: En studie om transformatorer2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project was carried out on behalf of the unit for Computer

    and Electrical engineering at the School of Technology and Health, KTH.

    This study about transformers, their function and uses, the way they’re

    built, how the core and windings, which are the most important parts of a

    transformer, are made and what kind of materials are used to make them.

    Several types of transformers and their functions are described. A crucial

    part of the study has been to search for different ways to develop

    transformers to make them environmentally safer and to increase their

    life-span. As such this work describes different transformer oils, what

    advantages and disadvantages they have compared to mineral oils, what

    properties they have and in what way they’re less harmful for the

    environment. HVDC units transform high voltages from Alternating

    Current to Direct Current to lessen the resistive losses and energy losses

    which lead to a cleaner environment.

    The theory examination of the transformer is the basis for the formation

    of a lab for educational use, among others in a course about electrical

    power that’s included in Bachelor of Science in Electrical Engineering at

    KTH.

  • 3433.
    Albrektsson, Fredrik
    KTH, School of Computer Science and Communication (CSC).
    Detecting Sockpuppets in Social Media with Plagiarism Detection Algorithms2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As new forms of propaganda and information control spread across the internet, the need for novel ways of identifying them increases as well. One increasingly popular method of spreading false messages on microblogs like Twitter is to disseminate them from seemingly ordinary, but centrally controlled and coordinated user accounts – sockpuppets. In this paper we examine a number of potential methods for identifying these by way of applying plagiarism detection algorithms for text, and evaluate their performance against this type of threat. We identify one type of algorithm in particular – that using vector space modeling of text – as particularly useful in this regard.

  • 3434.
    Albrektsson, Joakim
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures. SP Technical Research Institute of Sweden.
    Durability of fire exposed concrete: Experimental Studies Focusing on Sti„ffness & Transport Properties2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Road and rail tunnels are important parts of the modern infrastructure. High strength concrete (HSC) is commonly used for tunnels and other civil engineering structures, since it allows high load carrying capacity and long service life. In general, Swedish road and rail tunnels should be designed for a service life of 120 years. However, HSC has shown to be sensitive to severe fires in the moist tunnel environment, i.e., fire spalling may occur. Extensive research shows that addition of polypropylene (PP) fibres in the fresh concrete mix significantly reduces the risk of fire spalling. The durability of a concrete structure is mainly governed by the transport properties. Further, experimental studies aimed at understanding the protective mechanism of PP fibres indicate that fluid transport increases in connection with the melting temperature of such fibres. This might reduce the durability of fire exposed concrete with addition of PP fibres. This study aims to investigate whether the use of PP fibres has any significant effect on the durability of moderate fire exposed concrete structures.

    The experimental study focused on transport properties related to durability and stiffness reduction of fire exposed civil engineering concrete with and without addition of PP fibres. The study consists of three parts; (i) unilateral fire exposure in accordance with the standard time-temperature curve (Std) and a slow heating curve (SH), (ii) uniformly heating of non-restrained samples to 250oC, and (iii) moderate unilateral fire exposure, 350oC, of restrained samples. Changes in material properties caused by the fire exposure were studied by means of ultrasonic pulse velocity, full field-strain measurements during uniaxial compression core tests, polarization and fluorescence microscopy (PFM), water absorption and non-steady state chloride migration.

    The study shows that fire exposure influences different properties of importance for load carrying capacity and durability. To get a clear image of the fire damage one has to combine different test methods during damage assessments. Transport properties of concrete both with and without addition of PP fibres were considerably affected even at moderate fire exposure. Hence, the service life might be reduced. All series with addition of PP fibres exhibited higher water absorption compared to the series without PP fibres. The practical importance of this might, however, be small since also the water absorption of concrete without PP fibres was considerably affected for the fire scenarios considered in this study. Behind the fire exposed surface, i.e., between 30 and 60 mm, no change in water absorption was observed for concrete without PP fibres. However, higher water absorption of the series with addition of PP fibres was observed.

    Indicative fire tests aimed to evaluate the resistance to fire spalling during a subsequent severe fire was also conducted. The concretes with addition of PP fibres showed no signs of fire spalling, while progressive spalling was observed for the concrete without PP fibres.

  • 3435.
    Albrektsson, Joakim
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Flansbjer, M.
    CBI .
    Lundqvist, J. E.
    Jansson, Robert
    Assessment of fire exposed concrete with full-field strain determination2011In: 2nd International RILEM Workshop on Concrete Spalling due to Fire Exposure, 2011, p. 337-344Conference paper (Refereed)
    Abstract [en]

    A concrete structure exposed to fire deteriorates when the temperature increase in the structure. An experimental study has been performed in order to evaluate the degree of degradation of concrete exposed to two different fire scenarios. As the thermal diffusivity of concrete is low, high thermal gradient is induced in the cross-section. This causes inhomogeneous mechanical properties of a concrete structure. In traditionally core testing of the elastic modulus and compressive the material is assumed to be homogeneous, this is not the case when concrete has been exposed to a real fire. By using an optical full-field strain measuring device the mechanical response at different depth, from the fire exposed surface, can be studied. In this study a typical concrete mix for civil engineer applications were used. In addition a similar concrete mix with reduced aggregate size was tested. The test samples were exposed to the standard fire curve ISO 834-1 or a temperature rise of 10 °C/min. In addition, Ultrasonic Pulse Velocity measurement and PFM Microscopy were conducted in order obtain a reliable picture of the residual mechanical properties and the durability.

  • 3436.
    Albrektsson, Joakim
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Jansson, Robert
    Capillary suction and chloride migration in fire exposed concrete with PP-fibre2012In: Concrete Repair, Rehabilitation and Retrofitting III (ICCRRR), 2012, p. 128-129Conference paper (Refereed)
    Abstract [en]

    Annually, several concrete structures, such as buildings, bridges, parking garages, tunnels, etc. are exposed to fires. Many fires are small, for example single car fires in tunnels. These fires do not affect the load carrying capability of the concrete structure and thus minor or no reparations are required. In modern concrete for civil engineer applications the use of Polypropylene fibres (PP-fibre) to reduce fire spalling is growing. Some studies have been carried out which indicate that the use of PP-fibres will not affect the durability of the concrete. But in case of a fairly moderate fire exposure, a fire exposure that does not lead to structural damage, the PP-fibres can potentially lead to reduced durability. During low intensity fires or at long distances downstream a large fire in a tunnel the PP-fibres melts and form channels in the concrete. After such degradation of the PP-fibres it is plausible that accelerated damage may occur when moisture, de-icing salts and carbon dioxide can more easily penetrate the concrete. In this experimental study the chloride migration and the capillary suction are studied in moderately heated concrete containing PP fibres. The chloride migration tests were conducted with heated samples with and without PP-fibres. The capillary suction tests were even conducted with different fibre contents. As a reference the results are compared with results from unheated concrete. The aim of the project is to define whether or not measures have to be taken to repair concrete structures after small fires and at long distances downstream from large fires in tunnels. If the durability is affected the costs and consequences of not repairing and refurbishing after the fire can potentially be very high especially after a fires in very long tunnel.

  • 3437.
    Albrektsson, Joakim
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Jansson, Robert
    Silfwerbrand, Johan
    CBI .
    Assessment of fire exposed concrete structures2012In: Symposium 2012, 2012, p. 619-622Conference paper (Refereed)
    Abstract [en]

    Annually, several concrete structures, such as buildings, bridges, parking garages and tunnels are exposed to fires. An assessment is then necessary to decide whether the structure can be repaired or needs to be replaced. In a recent research project, recommendations for assessments of fire exposed concrete structures have been developed. The recommendations are based on a literature survey, results from an experimental study, where ultrasonic measurements, microscopy, Digital Image Correlation (DIC) measurement on loaded core samples were used and practical experience of real post-fire structural assessments. A refined assessment of the fire damage is obtained by combining these test methods.

  • 3438.
    Albrektsson, Joakim
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Jansson, Robert
    Silfwerbrand, Johan
    CBI .
    Durability of fire exposed concrete cover considering non-linear thermal gradient, boundary effecs and polypropylene fibresManuscript (preprint) (Other academic)
  • 3439.
    Albutov, Alexey
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Reducing Energy Consumption through Optimization of the Operating Conditions of the Gas Trunk Pipeline2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Gas supplying process for consumers needs sufficient share of energy for upstream, midstream and downstream purposes. In spite of a huge amount of great investments into the industry it is still available to improve the efficiency of energy usage inside the industry. The biggest share of energy consumption is within transportation sector. Optimization of operating conditions of gas pipeline is a one of the cheapest ways for reducing energy consumption. Optimization doesn’t need any investments into the industry. It works only within operating parameters. Adjustable operating parameters of a gas pipeline are operative pressure, rotation speed of compressors, amount of operating units, gas temperature after a compressor station and others. The energy consumption depends on the combination of the parameters which determine an appropriate operation mode to provide the particular gas flow through a pipeline, the maximum capacity, the minimum energy consumption and others. From energy saving point of view it is possible to reduce energy demand in the gas industry due to optimization of the operation mode. A few approaches to achieving energy reduction through optimization are investigated in this work and presented in this article, such as saving energy through changing of loading between compressor stations, varying the depth of gas cooling and changing the loading of gas pumping units. The results of analyzing inside the study model reflect the possibility for improving efficiency of gas trunk pipelines.

  • 3440.
    Albåge Sandberg, Mikael
    KTH, School of Computer Science and Communication (CSC).
    Anpassning av en interaktiv skrivtavla till svenska klassrum.2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    During recent years interactive writing boards (digital whiteboards) have become very popular in classrooms. Many schools choose to renovate their classrooms and are then considering the possibility of equipping the classrooms with a computer, projector and an interactive writing board. The interactive writing board can be used like a regular whiteboard, but offers new possibilities such as playing back recorded media files. There are a many different applications available since the interactive whiteboard uses a normal computer. The lessons can be saved on the computer and the lessons can be repeated with the students. The lesson files can easily be distributed via e-mail or web pages.

    This report show encountered limitations and possibilities to improve the software for the interactive writing board ePLUS. The study is based on a literature study and teacher interviews. A prototype software was also developed which was then evaluated using further interviews.

    The results in this report show that the large number of different programs confuses the users who easily mix up the different features in the programs. Remarkably few of the interviewed teachers actually use the digital pen actively in their teaching. This is probably a result of poor education or lack of interest. In order to improve the use of ePLUS in the schools, the software has to be very flexible and fit both basic and advanced users. This could be obtained by introducing a “difficulty setting” which can be set by the user. This setting could control the number of visible buttons and available features. Many improvements can be made, but there is also a limit in how many specialized features that can actually be implemented. Many of the interviewed teachers requested special features or premade lessons adapted to their teaching habits. It is however difficult to implement many special features without affecting the complexity of the software.

    The research was primarily aimed at software issues, but it also revealed that the classrooms in many schools need to be adapted to the new technology in order to utilize it better. As an example is it sometimes difficult to control the room lighting. The position of the projector screen is also sometimes hindering the education. It is very important that the teachers get sufficient education in the software, in order for them to feel comfortable using the writing board.

  • 3441. Albèr, C.
    et al.
    Brandner, B. D.
    Björklund, S.
    Billsten, P.
    Corkery, Robert
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Engblom, J.
    Effects of water gradients and use of urea on skin ultrastructure evaluated by confocal Raman microspectroscopy2013In: Biochimica et Biophysica Acta - Biomembranes, ISSN 0005-2736, E-ISSN 1879-2642, Vol. 1828, no 11, p. 2470-2478Article in journal (Refereed)
    Abstract [en]

    The rather thin outermost layer of the mammalian skin, stratum corneum (SC), is a complex biomembrane which separates the water rich inside of the body from the dry outside. The skin surface can be exposed to rather extreme variations in ambient conditions (e.g. water activity, temperature and pH), with potential effects on the barrier function. Increased understanding of how the barrier is affected by such changes is highly relevant for regulation of transdermal uptake of exogenous chemicals. In the present study we investigate the effect of hydration and the use of a well-known humectant, urea, on skin barrier ultrastructure by means of confocal Raman microspectroscopy. We also perform dynamic vapor sorption (DVS) microbalance measurements to examine the water uptake capacity of SC pretreated with urea. Based on novel Raman images, constructed from 2D spectral maps, we can distinguish large water inclusions within the skin membrane exceeding the size of fully hydrated corneocytes. We show that these inclusions contain water with spectral properties similar to that of bulk water. The results furthermore show that the ambient water activity has an important impact on the formation of these water inclusions as well as on the hydration profile across the membrane. Urea significantly increases the water uptake when present in skin, as compared to skin without urea, and it promotes formation of larger water inclusions in the tissue. The results confirm that urea can be used as a humectant to increase skin hydration.

  • 3442.
    Alcala, Yvonne
    et al.
    New York Medical College .
    Olivecrona, Henrik
    Karolinska.
    Olivecrona, Lotta
    Karolinska.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Zeleznik, Michael P.
    Sollerman, Christer
    Sahlgrenska University Hospital, Göteborg, Sweden.
    Qualifying CT for wrist arthroplasty: Extending techniques for total hip arthroplasty to total wrist arthroplasty2005In: Medical Imaging 2005: Image Processing, Pt 1-3 / [ed] Fitzpatrick, JM; Reinhardt, JM, SPIE - The International Sooceity for Optical Engineeering , 2005, Vol. 5747, p. 1155-1164Conference paper (Refereed)
    Abstract [en]

    The purpose of this study was to extend previous work to detect migration of total wrist arthroplasty non-invasively, and with greater accuracy. Two human cadaverous arms, each with a cemented total wrist implant, were used in this study. In one of the arms, I mm tantalum balls were implanted, six in the carpal bones and five in the radius. Five CT scans of each arm were acquired, changing the position of the arm each time to mimic different positions patients might take on repeated examinations. Registration of CT volume data sets was performed using an extensively validated, 3D semi-automatic volume fusion tool in which co-homologous point pairs (landmarks) are chosen on each volume to be registered. Three sets of ten cases each were obtained by placing landmarks on 1) bone only (using only arm one), 2) tantalum implants only, and 3) bone and tantalum implants (both using only arm two). The accuracy of the match was assessed visually in 2D and 3D, and numerically by calculating the distance difference between the actual position of the transformed landmarks and their ideal position (i.e., the reference landmark positions). All cases were matched visually within one width of cortical bone and numerically within one half CT voxel (0.32 mm, p = 0.05). This method matched only the bone/arm and not the prosthetic component per se, thus making it possible to detect prosthetic movement and wear. This method was clinically used for one patient with pain. Loosening of the carpal prosthetic component was accurately detected and this was confirmed at surgery.

  • 3443.
    Alcalá Borao, Raquel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Oxidation of pharmaceuticals by chlorine dioxide in wastewater effluent.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The presence of pharmaceuticals in the environment has raised an emerging interest due to the fact that they pose negative environmental impact and health hazards related to long-term toxicity effects. As conventional treatments are not able to totally remove these substances it is necessary to seek for alternative advanced technologies such as oxidation with chlorine dioxide (ClO2). The objective of this master thesis is thus to find the most optimal dose – reaction time of ClO2 for the oxidation and maximum removal of selected environmentally relevant pharmaceuticals. Factorial design and subsequent optimization with MODDE was selected as the best approach to find the optimal dose – time. Batch oxidation tests were conducted on 100mL aliquots treated with ClO2 using wastewater effluent from Henriksdal WWTP. Thereafter solid phase extraction and final determination of pharmaceuticals was carried out on a high performance liquid chromatography- triple quadrupole mass spectrometry (HPLC-MS/MS). Results showed that applying a dose of 5 mg ClO2/L and a reaction time of 10 minutes, it is possible to remove more than a half of the 17 analyzed substances. Besides most of the pharmaceuticals with high and moderate environmental risk, would pose a low risk for the environment after treatment with the optimal ClO2 dose – reaction time. Despite the fact that ClO2 could successfully degrade most environmentally relevant pharmaceuticals, deeper research concerning the formation of toxic by-products after oxidative treatment needs to be done before upscaling this technology to pilot or full scale as a suitable end of pipe technology for pharmaceuticals removal.

  • 3444.
    Alcalá Perales, Diego
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics. UPV.
    Spatial variation in uplift pressure and correlation with rock mass conditions under two buttress dams: A case study of Ramsele and Storfinnforsen dams2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Uplift water pressure is one of the dominating forces with signicant impact acting on a dam. It is usually measured with piezometers installed along the dam. However, the value of the pressure along the dam is often hard to measure due to the limited number of piezometers available (Bernstone et al., 2009). Furthermore, uplift pressure can oscillate substantially in a single hole both with time and also spatially under the dam due to the combination of rock mass characteristics in the foundation, loads and temperature variations.There is still a lack of information regarding the magnitude and variation of the uplift pressure. The aim of this thesis is to investigate the spatial variation of the uplift pressure based on uplift pressure measurements taken from Storfinnforsen and Ramsele dams. The aim is also to investigate how the uplift pressure depends on the rock mass conditions. The two dams Storfinnforsen and Ramsele provides a unique opportunity due to the signicant amount of piezometers, 270 in total, installed along the rock foundation for the new monitoring programme at the monoliths of both dams.Based on the measured uplift pressure, a probabilistic distribution has been assigned to the uplift pressure. In addition, a possible correlation between the rock mass quality and the uplift pressure as well as the joint aperture and the uplift pressure was analysed.

  • 3445.
    Alcaraz Bosca, Neus
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Industrial Economics and Management (Div.).
    Lean project management. Assessment of project risk management processes2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Traditional methods of project management are not appropriate for complex projects anymore. Since projects are becoming increasingly complex and uncertain, interaction between activities and resources is growing in ways not considered by these methods. Nowadays, managers need more agile project management methods that are able to recognize and deal with uncertainty and to produce the expected results. Lean project management, the most recent approach of lean methodology, appears as an alternative approach capable of dealing with complexity and uncertainty. The latest investigations in the field show that traditional methods are still adequate for simple projects, while lean methods are more appropriate for complex projects.

    This thesis aims to investigate the nature of lean project management and to examine project risk management processes so that managers can assess the complexity of projects before their beginning and decide which method to apply in order to manage them. 

  • 3446.
    Alci, Kenan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    TFTP loading of programs into a Microcontroller’s flash memory and evaluation of Microchip’s TCP/IP stack with ENC28J602014Report (Other academic)
    Abstract [en]

    This project began with a microprocessor platform developed by two master’s students: Albert López and Francisco Javier Sánchez. Their platform was designed as a gateway for sensing devices operating in the 868 MHz band. The platform consists of a Texas Instruments MSP430F5437A microcontroller and a Microchip ENC28J60 Ethernet cont roller connected to the MSP430 processor by a Serial Peripheral Interface.

    Javier Lara Peinado implemented prototype white space sensors using the platform developed by the earlier two students. As part of his effort, he partially implemented a Trivial File Transfer Protocol (TFTP) system for loading programs in to the flash memory of the microcontroller using Microchip’s TCP/IP stack.  However, he was not successful in loading programs into the flash as the TFTP transfer got stuck at the first block.

    The first purpose of this project was to find and fix the error(s) in the TFTP loading of programs into the MSP430’s flash memory. The second purpose of this project was to evaluate Microchip’s TCP/IP stack in depth.  This report describes measurements of UDP transmission rates. Additionally, the TFTP processing rate is measured and the TFTP program loading code is documented.  The report concludes with suggestions for possible improvements of this system.

  • 3447.
    Alcocer Bonifaz, Joaquin
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Design of High Performance Flanges and its Influence on Manufacturing Costs, Structural Performance and Weight2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This project attempts to research the manufacturing cost, with an emphasis on machining, of high performance flanges for Turbine Rear Structure (TRS) applications, as well as the tradeoffs with structural performance and weight. A combination of traditional cost modelling techniques from the literature, as well as, the non-conventional manufacturing complexity index, as cost indicator are implemented. A multidisciplinary study is carried out with the aid of ANSYS Workbench in the form of computer simulated experiments to investigate tradeoffs in flanges. It is concluded that multidisciplinary studies of cost, performance and weight lacked model robustness to draw sound conclusions about flange design. However, the manufacturing complexity index after partial validation with experienced engineers shows promising results, and could be a way forward to estimate final machining operation cost for flanges in the future.

  • 3448.
    Alcusa-Saez, E. P.
    et al.
    ICMUV, Dept Fis Aplicada & Electromagnetismo, Dr Moliner 50, Burjassot 46100, Spain..
    Diez, A.
    ICMUV, Dept Fis Aplicada & Electromagnetismo, Dr Moliner 50, Burjassot 46100, Spain..
    Margulis, W.
    KTH, School of Engineering Sciences (SCI), Applied Physics. Acreo AB, Dept Fiber Photon, Elect 236, S-16440 Kista, Sweden..
    Norin, L.
    KTH, School of Engineering Sciences (SCI), Applied Physics. Acreo AB, Dept Fiber Photon, Elect 236, S-16440 Kista, Sweden..
    Andres, M. V.
    ICMUV, Dept Fis Aplicada & Electromagnetismo, Dr Moliner 50, Burjassot 46100, Spain..
    Acousto-optic interaction in polyimide coated optical fibers2017In: 2017 CONFERENCE ON LASERS AND ELECTRO-OPTICS EUROPE & EUROPEAN QUANTUM ELECTRONICS CONFERENCE (CLEO/EUROPE-EQEC), IEEE , 2017Conference paper (Refereed)
  • 3449. Alcusa-Saez, E. P.
    et al.
    Diez, A.
    Rivera-Perez, E.
    Margulis, Walter
    KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
    Norin, Lars
    ACREO.
    Andres, M. V.
    Acousto-optic interaction in polyimide coated optical fibers with flexural waves2017In: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 25, no 15, p. 17167-17173Article in journal (Refereed)
    Abstract [en]

    Acousto-optic coupling in polyimide-coated single-mode optical fibers using flexural elastic waves is demonstrated. The effect of the polyimide coating on the acoustooptic interaction process is analyzed in detailed. Theoretical and experimental results are in good agreement. Although the elastic attenuation is significant, we show that acousto-optic coupling can be produced with a reasonably good efficiency. To our knowledge, it is the first experimental demonstration of acousto-optic coupling in optical fibers with robust protective coating.

  • 3450. Alcusa-Saez, E. P.
    et al.
    Diez, A.
    Rivera-Perez, E.
    Margulis, Walter
    KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
    Norin, Lars
    Andres, M. V.
    All-fiber acousto-optic tunable filter in polyimide coated optical fibers2017In: 2017 19th International Conference on Transparent Optical Networks (ICTON), IEEE Computer Society, 2017, article id 8025093Conference paper (Refereed)
    Abstract [en]

    We present the experimental demonstration of in-fiber acousto-optic coupling in a polyimide-coated optical fiber. Although the presence of the polyimide coating increases is significantly the attenuation of the acoustic wave, we show that acousto-optic interaction can still be produced with reasonable efficiency. The effect of the polyimide coating on the acousto-optic interaction process is analyzed in detailed. Theoretical and experimental results are in good agreement. To our knowledge, this is the first experimental demonstration of acousto-optic coupling in optical fibers with robust protective coating.

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