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  • 201.
    Abedini, Pegah
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Lag 2010:879 om allmännyttiga kommunala bostadsaktiebolag: Hur den implementerats av aktörerna2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund:

    Den första januari 2011 trädde lagen om allmännyttiga kommunala bostadsaktiebolag i kraft. Dess ändamål var att jämställa konkurrensen sinsemellan de privata fastighetsägarna och de allmännyttiga kommunala bostadaktiebolagen. Lagen yrkade främst på att de allmännyttiga kommunala bostadsaktiebolagen skulle agera mer affärsmässigt för att konkurrensen inte skulle snedvridas. Kommunen som ägare var bland annat tvungen att ställa tydligare krav på bolagen genom att ta ut marknadsmässiga borgensavgifter och låneräntor samt ställa marknadsmässiga avkastningskrav.

    Frågan är nu hur de allmännyttiga kommunala bostadsaktiebolagen agerat utifrån dessa nya förutsättningar sedan lagen trädde i kraft den 1 januari 2011. Uppsatsen syftar till att undersöka hur den nya lagen om allmännyttiga kommunala bostadsaktiebolag har implementerats av aktörerna på bostadshyresmarknaden. Målet med uppsatsen är att klarlägga konsekvenserna av lagen för aktörerna på bostadshyresmarknaden, tydliggöra dess implikationer för beslutsfattare i de kommunala bostadsaktiebolagen samt kunna ge kommunerna bättre underlag i besluten rörande sina bolag.

    Metod:

    Enkätstudie där vd:ar från allmännyttiga kommunala bostadsaktiebolag har tillfrågats angående bolagets och kommunens agerande och inställning sedan lagen ikraftträdde.

    Avgränsning:

    Enkätstudien har avgränsats till att omfatta vd:ar på kommunala bostadsaktiebolag i Sverige, rörande händelser som inträffat sedan den 1 januari 2011. Vd:ar på bolag belägna i Stockholms Län, Uppsala län, Södermanlands Län, Östergötlands Län, Jönköpings Län samt Västra Götalands Län har medverkat i enkäten.

    Resultat och slutsats:

    De kommunala allmännyttiga bostadsaktiebolagen instämmer allmänt i att de agerar mer affärsmässigt sedan den nya lagen introducerades. Avkastningskraven i ägardirektiven har setts över, och de kommunala borgens– och ränteavgifterna har generellt sett ökat sedan lagen trädde i kraft.

  • 202. Abel, S
    et al.
    Bäbler, Matthäus
    ETH, Inst Chem & Bioengn, Dept Chem & Appl Biosci.
    Arpagaus, C
    Mazzotti, M
    Stadler, J
    Two-fraction and three-fraction continuous simulated moving bed separation of nucleosides2004In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1043, no 2, p. 201-210Article in journal (Refereed)
    Abstract [en]

     A new experimental set-up and a new simulated moving bed (SMB) operation are presented in this work. A desktop SMB unit developed as a modification of the commercial AKTA(TM) explorer working platform has been utilized for the separation of different mixtures of nucleosides. Both two fraction and three fraction SMB separations have been carried out, the latter made possible by the adoption of a new SMB configuration and operating mode (three fraction SMB, 3F-SMB, operation). Experiments demonstrate the feasibility of the 3F-SMB operation, and confirm the trends predicted based on considerations about retention of the components to be separated along the unit. 

  • 203.
    Abela,, Eric
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Davidsson, Rasmus
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Flexibility in the Office Market – A casestudy of the serviced office space ofGarnisonen2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The market for serviced office space has gone from previously solely consisting of premises in poor

    locations and of poor standards to presently consisting of a wide spectrum of properties ranging in

    location, standard and level of service. As the demand for flexibility increases in society, the serviced

    office space has become an increasingly greater part of the total office market and an important

    complement to the ordinary office market, in order to stimulate growth for smaller companies.

    The aim of this thesis is to investigate how the demand for serviced office space in B-locations in

    Stockholm is shaped and how important different factors are for businesses when choosing serviced

    office space. With this in mind we will then form a recommendation for how the serviced office space

    “Garnisonen” should be positioned on the market.

    To answer these questions a case study of Garnisonen serviced office space was conducted. Data has

    been collected through interviews, surveys and a literature review.

    Through our work we found that tenants that chose serviced office spaces in B-locations in Stockholm

    put the highest value in flexibility, simplicity, and the possibility to lease a fully functional office with

    only a few places.

    The physical environment isn’t the primary factor for success of serviced office space in B-locations in

    Stockholm. One of the most important factors for success, and to achieve tenant satisfaction, of serviced

    office space is to create a platform for networking between different companies and to create a social

    place where the companies can meet, which furthers their collective growth.

  • 204.
    Abela, Eric
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Qattan, Nessrin
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Transaktioner på den kommersiella fastighetsmarknaden 2011: Trender och fallstudier2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med detta examensarbete är att kartlägga några av de största transaktionerna på den svenska fastighetsmarknaden under 2011. Detta år har kännetecknats av lägre transaktionsvolym än föregående år, bland annat på grund av ett osäkrare ekonomiskt läge.

    Teorin har sin utgångspunkt i vilka aktörer som finns på marknaden och vilken roll konsulten, utländska investerare och banker spelar samt hur utvecklingen av fastighetstransaktions marknaden i Sverige sett ut fram tills idag. Kartläggningen har gjorts på sätt att försöka få med de flesta typer av aktörer och utreda varje transaktion för sig samt ge en närmare analys av dessa.

    Kartläggningen visar att de största transaktionerna i Sverige under 2011 gjordes av både noterade och onoterade fastighetsbolag på köpsidan, samt onoterade fastighetsbolag på säljsidan.

    Att döma av fjolårets utveckling marknadsmässigt pekar en hel del på att den kraftiga tillväxten i Sverige kommer att leda till mer arbetstillfällen, med fallande vakanser och stigande hyror som konsekvens på den svenska fastighetsmarknaden.

  • 205.
    Abele, Andreas
    et al.
    Continental Gmbd, Germany.
    Johansson, Rolf
    SP.
    Lönn, Henrik
    Volvo Technology AB.
    Papadopoulos, Yiannis
    Hull University, UK.
    Reiser, Mark-Oliver
    Technical Univ of Berlin.
    Servat, David
    CEA, France.
    Törngren, Martin
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Embedded Systems.
    Weber, Matthias
    Technische Universit¨at Berlin, DE.
    The CVM framework: A prototype tool for compositional variability management2010In: Proceeding of: Fourth International Workshop on Variability Modelling of Software-Intensive Systems, 2010, p. 101-105Conference paper (Refereed)
    Abstract [en]

    This article announces the first public release ofan experimental research tool for variability management,called “CVM framework” and provides an overview of thetool’s capabilities and architecture.

  • 206.
    Abelin, Sarah
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Investigation of integrated waterlevel sensor solution forsubmersible pumps: A study of how sensors can be combined towithstand build-up materials and improvereliability in harsh environment2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Monitoring water level in harsh environment in order to handle the start and stop function of drainage pumps has been a major issue. Several environmental factors are present, which affect and disturb sensor measurements. Current solutions with mechanical float switches, mounted outside of pumps, wear out, get entangled and account for more than half of all the emergency call outs to pumping stations. Since pumps are frequently moved around, a new sensor solution is needed which can be integrated within the pump house and is able to continuously monitor water level to optimize the operation of the pump and to decrease wear, cost and energy consumption.

    This thesis presents an investigation how different sensor techniques can be combined to improve reliability for monitoring water level and handle the start and stop function of drainage pumps in harsh environment. The main focus has been to identify suitable water level sensing techniques and to investigate how sensors are affected by build-up materials building up on the pump surface and covering the sensor probes. A support vector machine algorithm is implemented to fuse sensor data in order to increase reliability of the sensor solution in contaminated condition.

    Results show that a combination of a pressure sensor and a capacitive sensor is the most suitable combination for withstanding build-up materials. For operating conditions when sensors are covered with soft or viscous build-ups, sensors were able to monitor water level through the build-up materials. No solution was found that could satisfactorily monitor water level through solidified build-up materials.

  • 207.
    Abella, Tricia Jennifer
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.).
    The Creative Approach to Vanguard Projects2011Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A vanguard project is the firm’s entrepreneurial vehicle for exploring opportunities, creating new products, services or markets. This type of projects requires flexibility and innovation to thrive. In this regard, a creative approach to project management is proposed for the successful execution of such projects. This creative approach is summarized in a framework that consists of two main components – flexible planning and creative climate.

    The Central Services project, a vanguard in telecommunications, was used to benchmark the creative project management framework to the current project management methodology of the IT department of TIWS. Results show that there is a gap between the framework and the status quo. Moreover, the Central Services project is not efficiently and effectively managed, therefore, resulting to project delays which consequentially lead to negative company revenues. This reality strengthens the proposition that vanguard projects should be managed differently; hence, the birth of creative project management.

  • 208. Aberer, Karl
    et al.
    Alima, Luc Onana
    Ghodsi, Ali
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Girdzijauskas, Sarunas
    Ecole Polytechnique Fédérale de Lausanne.
    Haridi, Seif
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Hauswirth, Manfred
    The Essence of P2P: A Reference Architecture for Overlay Networks2005In: Fifth IEEE International Conference on Peer-to-Peer Computing, Proceedings / [ed] Caronni, G; Weiler, N; Waldvogel, M; Shahmehri, N, 2005, p. 11-20Conference paper (Refereed)
    Abstract [en]

    The success of the P2P idea has created a huge diversity of approaches, among which overlay networks, for example, Gnutella, Kazaa, Chord, Pastry, Tapestry, P-Grid, or DKS, have received specific attention from both developers and researchers. A wide variety of algorithms, data structures, and architectures have been proposed. The terminologies and abstractions used, however have become quite inconsistent since the P2P paradigm has attracted people from many different communities, e.g., networking, databases, distributed systems, graph theory, complexity theory, biology, etc. In this paper we propose a reference model for overlay networks which is capable of modeling different approaches in this domain in a generic manner It is intended to allow researchers and users to assess the properties of concrete systems, to establish a common vocabulary for scientific discussion, to facilitate the qualitative comparison of the systems, and to serve as the basis for defining a standardized API to make overlay networks interoperable.

  • 209. Abermann, S.
    et al.
    Efavi, J. K.
    Sjoblom, G.
    Lemme, Max C.
    AMO GmbH, AMICA, Aachen, Germany.
    Olsson, J.
    Bertagnolli, E.
    Processing and evaluation of metal gate/high-kappa/Si capacitors incorporating Al, Ni, TiN, and Mo as metal gate, and ZrO2 and HfO2 as high-kappa dielectric2007In: Microelectronic Engineering, ISSN 0167-9317, E-ISSN 1873-5568, Vol. 84, no 5-8, p. 1635-1638Article in journal (Refereed)
    Abstract [en]

    We evaluate various metal gate/high-K/Si capacitors by their resulting electrical characteristics. Therefore, we process MOS gate stacks incorporating aluminium (Al), nickel (Ni), titanium-nitride (TiN), and molybdenum (Mo) as the gate material, and metal organic chemical vapour deposited (MOCVD) ZrO2 and HfO2 as the gate dielectric, respectively. The influence of the processing sequence - especially of the thermal annealing treatment - on the electrical characteristics of the various gate stacks is being investigated. Whereas post metallization annealing in forming gas atmosphere improves capacitance-voltage behaviour (due to reduced interface-, and oxide charge density), current-voltage characteristics degrade due to a higher leakage current after thermal treatment at higher temperatures. The Flatband-voltage values for the TiN-, Mo-, and Ni-capacitors indicate mid-gap pinning of the metal gates, however, Ni seems to be thermally unstable on ZrO2, at least within the process scheme we applied.

  • 210. Abermann, S.
    et al.
    Efavi, J.
    Sjoblom, G.
    Lemme, Max C.
    AMO GmbH, AMICA, Aachen, Germany.
    Olsson, J.
    Bertagnolli, E.
    Impact of Al-, Ni-, TiN-, and Mo-metal gates on MOCVD-grown HfO2 and ZrO2 high-k dielectrics2007In: Microelectronics and reliability, ISSN 0026-2714, E-ISSN 1872-941X, Vol. 47, no 4-5, p. 536-539Article in journal (Refereed)
    Abstract [en]

    In this work we compare the impacts of nickel (Ni), titanium-nitride (TiN), molybdenum (Mo), and aluminium (Al), gates on MOS capacitors incorporating HfO2- or ZrO2-dielectrics. The primary focus lies on interface trapping, oxide charging, and thermodynamical stability during different annealing steps of these gate stacks. Whereas Ni, Mo, and especially TIN are investigated as most promising candidates for future CMOS devices, Al acted as reference gate material to benchmark the parameters. Post-metallization annealing of both, TiN- and Mo-stacks, resulted in very promising electrical characteristics. However, gate stacks annealed at temperatures of 800 degrees C or 950 degrees C show thermodynamic instability and related undesirable high leakage currents.

  • 211. Abermann, S.
    et al.
    Sjoblom, G.
    Efavi, J.
    Lemme, Max C.
    AMO GmbH, AMICA, Aachen, Germany.
    Olsson, J.
    Bertagnolli, E.
    Comparative study on the impact of TiN and Mo metal gates on MOCVD-grown HfO2 and ZrO2 high-kappa dielectrics for CMOS technology2007In: Physics of Semiconductors, Pts A and B, 2007, p. 293-294Conference paper (Refereed)
    Abstract [en]

    We compare metal oxide semiconductor capacitors, investigating Titanium-Nitride and Molybdenum as gate materials, as well as metal organic chemical vapor deposited ZrO2 and HfO2 as high-kappa dielectrics, respectively. The impact of different annealing steps on the electrical characteristics of the various gate stacks is a further issue. The positive effect of post metallization annealing in forming gas atmosphere as well as observed mid-gap pinning of TiN and Mo metal gates is presented.

  • 212.
    Abeywardana, Asela M.A.J.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Solar-Biomass hybrid system for process heat supply in medium scale hotels in Sri Lanka2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study aimed at evaluating and demonstrating the feasibility of using Concentrated Solar Thermal technology combined with biomass energy technology as a hybrid renewable energy system to supply the process heat requirements in small scale industries in Sri Lanka. Particularly, the focus was to apply the concept to the expanding hotel industry, for covering the thermal energy demand of a medium scale hotel.

    Solar modules utilize the rooftop area of the building to a valuable application. Linear Fresnel type of solar concentrator is selected considering the requirement of the application and the simplicity of fabrication and installation compared to other technologies. Subsequently, a wood-fired boiler is deployed as the steam generator as well as the balancing power source to recover the effects due to the seasonal variations in solar energy. Bioenergy, so far being the largest primary energy supply in the country, has a good potential for further growth in industrial applications like small hotels. 

    When a hotel with about 200-guests capacity and annual average occupancy of 65% is considered, the total annual CO2 saving is accounted as 207 tons compared with an entirely fossil fuel (diesel) fired boiler system. The annual operational cost saving is around $ 40,000 and the simple payback period is within 3-4 years. The proposed hybrid system can generate additional 26 employment opportunities in the proximity of the site location area.  

    This solar-biomass hybrid concept mitigates the weaknesses associated with these renewable technologies when employed separately. The system has been designed in such a way that the total heat demand of hot water and process steam supply is managed by renewable energy alone. It is thus a self-sustainable, non-conventional, renewable energy system. This concept can be stretched to other critical medium temperature applications like for example absorption refrigeration. The system is applicable to many other industries in the country where space requirement is available, solar irradiance is rich and a solid biomass supply is assured.

  • 213. Abeyweera, Ruchira
    et al.
    Senanayake, Nihal S.
    Senaratne, Chamindie
    Jayasuriya, Jeevan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. EIT InnoEnergy, Sweden.
    Fransson, Torsten H.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. EIT InnoEnergy, Sweden.
    Capacity Building Through a Web Based Master Degree Programme in Sustainable Energy Engineering2017In: PROCEEDINGS OF 2017 IEEE GLOBAL ENGINEERING EDUCATION CONFERENCE (EDUCON2017), IEEE, 2017, p. 800-805Conference paper (Refereed)
    Abstract [en]

    Open Distance Learning is gaining popularity as a successful alternative for on-campus higher education especially with the emergence of web based platforms which enable the online delivery of courses worldwide. This emerging educational pedagogy can successfully be employed as means of capacity building of the people living in the less fortunate parts of the world where higher education especially at master level are scarce. This paper presents a two-year collaborative master study programme in sustainable energy engineering offered in synchronous with an on-campus study programme conducted by the KTH Royal Institute of Technology of Sweden, to students of Sri Lanka, which was facilitated by the Open University of Sri Lanka. The paper describes the need of such a programme, the format of course delivery and assessment thereof, plus the benefits gained. This programme has produced 72 post graduates in Sri Lanka alone and more than 200 distant postgraduates worldwide in the field of sustainable energy engineering during last 10 years period. In terms of capacity building in the energy sector in Sri Lanka this is considered a great achievement. The experience gained by the local staff in the role of local facilitators who engaged in some of the academic related activities such as evaluation of students' presentation and co-supervision of thesis projects have been greatly appreciated as being additional benefits to the staff in terms of their own academic development and capacity building. Finally, conclusions are made on how remote programmes of study could successfully be delivered to places where such know-how is scarce by adapting appropriate technologies in training personnel at postgraduate level to meet the needs of the industry.

  • 214. Abeywickrama, Sandu
    et al.
    Furdek, Marija
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wong, Elaine
    Protecting core networks with dual-homing: A study on enhanced network availability, resource efficiency, and energy-savings2016In: Optics Communications, ISSN 0030-4018, E-ISSN 1873-0310, Vol. 381, p. 327-335Article in journal (Refereed)
    Abstract [en]

    Core network survivability affects the reliability performance of telecommunication networks and remains one of the most important network design considerations. This paper critically examines the benefits arising from utilizing dual-homing in the optical access networks to provide resource-efficient protection against link and node failures in the optical core segment. Four novel, heuristic-based RWA algorithms that provide dedicated path protection in networks with dual-homing are proposed and studied. These algorithms protect against different failure scenarios (i.e. single link or node failures) and are implemented with different optimization objectives (i.e., minimization of wavelength usage and path length). Results obtained through simulations and comparison with baseline architectures indicate that exploiting dual-homed architecture in the access segment can bring significant improvements in terms of core network resource usage, connection availability, and power consumption.

  • 215.
    Abhijeet, Kumar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Governing water pollution effectively: A comparative study of legal frameworks & their implementation in India & Sweden.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Case studies from India have shown that the legal regime governing water pollution control in India has miserably failed. Sectoral approach to water management is quite evident. On the other hand Sweden has shown a remarkable change with regard to environment management. The poor management of a resource makes the resource further poor. Thus effective management of the resources becomes crucial. Good governance has been vital in conservation of a resource. But the issue is what constitutes good governance with respect to water? Law has always played a steering role in governance aspect. But despite having pollution control laws the effective governance of water pollution has not been attainable in India. Are the pollution control laws fundamentally wrong or some other factors prevail which is beyond the reach of law to control the pollution problem. The thesis which is a comparative study of legal framework and their implementation in India and Sweden attempts to explore how control of water pollution has been effectively governed in Sweden and what needs to been done in India.

  • 216.
    Abid, Fahim
    et al.
    KTH.
    Ghorbani, Hossein
    Pourrahimi, Amir Masoud
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Edin, Hans Ezz
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Differences in morphology and polarization properties of heat-treated XLPE and LDPE insulation2016In: 2016 IEEE CONFERENCE ON ELECTRICAL INSULATION AND DIELECTRIC PHENOMENA (IEEE CEIDP), IEEE conference proceedings, 2016, p. 113-116Conference paper (Refereed)
    Abstract [en]

    Cross-linked polyethylene (XLPE) is the most commonly used insulating material for extruded high voltage cable applications. Degassing is a heat-treatment process that is performed to remove methane from XLPE insulation which is formed during the crosslinking reactions as a by-product. Apart from removing methane, heat-treatment influences the electrical properties through changing the morphology due to annealing and also removal of polar crosslinking by-products. Scanning electron microscopy (SEM) is generally used to observe the changes in crystalline structure of the polymer. Frequency domain spectroscopy (FDS) is widely used to study polarization properties of dielectric materials. In this study these two methods are used for a comparative analysis of XLPE and LDPE subjected to different heat-treatment time, with or without a diffusion barrier. Electrical measurements are performed at room temperature. From the SEM imaging conducted after permanganate acid etching, formation of spherulites due to heat-treatment is not obvious in neither LDPE nor in XLPE. However, distinctions between LDPE and XLPE in SEM micrographs are evident. From studies with dielectric polarization spectroscopy, it is found that the LDPE samples are less sensitive to heat-treatment in comparison to the XLPE samples while dissipation factor of XLPE samples are influenced by the choice of pressing film used during sample preparation.

  • 217.
    Abid, Muhammad
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.).
    Global Supply Chain Design: Exploring configurational and coordination factors2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis addresses the topic of global supply chain design. One major challenge concerns how to manage the tension between separation and integration pertaining to the localization of business activities. In this regard Ferdows (2008) worked to create two new production network models (rooted production network and footloose production network). Earlier studies have highlighted the choices that are involved in the network of facilities but lack in providing a comprehensive picture in terms of both configurational and coordination factors that govern the design of global supply chain. There is a need for a conceptual model where factors affecting the design process of a global supply chain can be applied. Two main research questions have been addressed in this study. First, exploring and identifying the factors affecting global supply chain design. Second, investigating the factors that influence the position on the spectrum of rooted and footloose supply chain design.      

    A literature review analysis and multi-case studies have been performed for this study in order to explore the factors. The companies were selected in order to reflect upon the two types of network, i.e., rooted and footloose. The primary data were selected through interviews with the managers.

    This study highlighted that there are many factors that affect configurational and coordination decision areas within a global supply chain. This study categorized the factors and the configurational/coordination decision areas with two main competitive priorities, i.e., cost and differentiation in the form of a “conceptual model.” The study also highlighted the factors in a matrix, which showed their position on the spectrum of rooted and footloose network configurations. For instance, the coordination factors that drive towards a footloose network include: high orchestration capabilities, need access to new technology and knowledge, proximity to suppliers, etc. The configurational factors that drive towards a rooted network include: economic stability, proximity to market, concerns for sustainability issues, high transportation cost, need for high proximity between key functions, need for intellectual property rights protection, etc.

  • 218.
    Abid, Muhammad
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.). Högskolan i Gävle, Sweden.
    Relationship between competitive priorities and global supply chain design: A conceptual frameworkManuscript (preprint) (Other academic)
  • 219.
    Abid, Muhammad
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.). Högskolan i Gävle, Sweden.
    Bengtsson, Lars
    Dabhilkar, Mandar
    Factors affecting shifts in global supply chain networks: A configurational approach2013In: Proceedings of the 20th International Annual EurOMA conference, Dublin, Ireland, 9-12 June 2013, 2013, 2013Conference paper (Refereed)
    Abstract [en]

    In certain situations, global companies strive to take advantage of short-term changes in economic and exchange rates on the never-ending journey of competitiveness. This paper seeks to extend Ferdows’s (2008) production network models by adding the factors affecting shifts between rooted and footloose network configurations. Two companies were selected in order to illustrate the models and reveal other possible factors. The identified factors are differentiated in terms of configuration and coordination and merged in a matrix. The trends and implications on global supply chains are also discussed.

  • 220.
    Abid, Muhammad
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.). Högskolan i Gävle, Sweden.
    Bengtsson, Lars
    Hellberg, Roland
    Dabhilkar, Mandar
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.).
    Factors affecting global supply chain design2012Conference paper (Refereed)
    Abstract [en]

    Due to the limited existing knowledge pertaining to the factors which govern localization of operations and capabilities in a global supply chain, the purpose of the paper is to find out which factors and how they jointly affect the design of global supply chains. The relevant literature is reviewed and a concept matrix is developed. Five companies were selected in order to illustrate the issues of global supply chain design. Among them, three companies are considered to have efficient supply chain and less complex products, while the two others are considered to have responsive supply chain and more complex products. The issues discussed with the selected companies cover global sourcing, challenges, technological advancement and issues related to management control. The study identifies about fifty factors that affect global supply chain design, and specifically how theses relate to design decisions on location of factories and production, supplier selection and development, distribution of products and organisation of interfaces along the supply chain. The discrepancies between theory and practice as well as the implications for further research are discussed.

  • 221.
    Abolafya, Natan
    KTH, School of Information and Communication Technology (ICT).
    Secure Documents Sharing System for Cloud Environments2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the current trend of cloud services available in every market area in IT business, it is somewhat surprising that security services are not migrated to the cloud widely. Security as a Service (SECaaS) model is hardly popular at the moment even though the infrastructure of the cloud, or web, can support most of the functionalities of conventional distributed security services.

    Another uncommon phenomenon in the cloud is sharing secure files with multi-tenant support. This kind of service would be best available integrated with a SECaaS platform that may offer more similar application services. This thesis proposes, studies, designs, develops and evaluates a Secure Documents Sharing System for Cloud Environment with the possibility of integrating to a SECaaS platform.

  • 222.
    Abou Jaoudeh, Elie
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Developement of Optimization Method/A Tool for RE applications in Intermittent Grids with focus on Lebanon2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Renewable energy applications require sound design and optimization of life cycle costs because they need upfront investments and as long as possible operating lifetimes are expected. Using modern tools for optimizing designs of grid-tied and autonomous plants allows investors to deploy these technologies while keeping risks within acceptable limits.

    Nevertheless in Lebanon, the grid is intermittent and the most adapted solutions are dual-mode plants that can operate autonomously and with grid-tie. There are no existent simulation models particularly adapted to optimize these applications for such a situation. The objective of this research is to suggest and test a model adapted from commercially available software that can simulate the particular conditions of Lebanon. The studied solution has a PV generator associated with a PV charge controller, lead acid battery, a dual mode inverter, and transfer switchgear and protections. The research successfully met the objective of finding a setup in HOMER 2.68beta for simulating and optimizing a PV-Battery AC plant for an intermittent grid with scheduled blackouts.

    The setup and adaptation in HOMER is made to replicate an existing reference PV-Battery plant at a public school. The measured data from this public school is used to validate the results obtained from the adapted HOMER simulation. The grid is supplied for an average of 12 hours per day at the reference site with a tariff of USD 0.1/kWh.

    After the validation process, a sensitivity analysis is performed to simulate this plant under

    1. Different grid supply hours, 12 and 18 hours of supply daily
    2. Different grid electricity prices, USD 0.1 and 0.1375 /kWh
    3. Simulation of PV plants to meet other load profiles typical of community and municipality building centers

    All the simulations cross matched 20 different PV generator sizes to 7 different battery sizes for 5 different total setups.

    The levelized cost of electricity, COE, is the main parameter used to find the optimum setups, whereas options that shortened the battery life to less than 12 years or couldn’t meet at least 90% of the required yearly load were filtered out. The COE is calculated manually since several corrections related to grid and net-metering limitations are not obtained directly from HOMER.

    The simulated results can serve as a good indicator on how the systems would perform for typical public institutions in Lebanon, given the current conditions, and knowing that the range of this study is limited to small scale institutions with consumption levels less than 30 kWh/day. Storage capacity should also be limited to 100 kWh/day of useful storage, since batteries are not the best option to use for storage capacities higher than the mentioned limit.

    The setup has a great potential for advancement and acts as a first step for Lebanon to have a specialized tool for simulating the performance of PV-battery AC plants optimized for the conditions existing in the country. Future steps could be made to improve and diversify the software to include:

    • irradiation data that come from actual data logging data from other PV sites which are installed around the whole country, almost a 100
    • financial analysis for offsetting private generation with fossil fueled gensets, which is the main backup for electricity blackouts
    • wind turbine simulations, several installations are provisioned to be completed by the end of 2012, and it would be possible to carry out a similar validation process for small wind turbines
    • pollution and other environmental costs
    • value of lost load, “VOLL”, to compare different options in parallel with COE.

  • 223.
    ABOUD, STEPHANIE
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    AL MANDLAWI, LINA
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Vilken påverkan har stora readagar på produktionen inom tillverkande företag?2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Major sales days like Black Friday and Cyber Monday are today widely used and established phenomena around the world. During these days, customers are offered unique offers and strong price reductions on products. Periods like these become important for manufacturing companies as they face more demands in terms of high customer expectations and an increased demand for products.

    The purpose of this work is to investigate whether major sales days have an impact on the production within manufacturing companies. More specifically, it is investigated if the production is made more effective ahead of these days and what methods that are used to forecast demand and to avoid potential risks.

    The question is answered by conducting two studies, a literature and a field study. The literature study gives a theoretical basis for the report. The field study contributes with the practical part as it consists of interviews with two well-established manufacturing companies and also a survey for consumers to respond to. This then gives a better understanding of how companies handle major sales days and of consumers demands and expectations.

    Results from interviews shows that companies control their customers, the resellers, in a matter of how many products they should order on these sales days. Thus, they control their own demand which reduced the need to make the production more effective. In case of increased pressure on the production, companies also take other measures such as hiring extra labour. The companies do not consider the fact that they overproduce to be a problem as they are certain the products will be purchased later.

    The main results from the survey shows that the products sought by the customers during major sales days are often sold out. The majority of these customers’ lack understanding of this which indicates that there is a gap between companies supply and customers’ demands and expectations.

    A conclusion was drawn based on an analysis of the field study in relation to the literature. Companies choose to not directly affect their production or make it more effective ahead of major sales days. However, they are affected from an economic point of view as they take costly measures when faster handling within the production is needed. Furthermore, it was concluded that the customers’ actual demands and expectations are not met during these days, which suggests that companies should reevaluate some of their methods and strategies.

  • 224.
    Aboudi, U
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Fluid and Climate Technology.
    Altaie, K
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Fluid and Climate Technology.
    Solvärme i krypgrunder2009Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 225.
    Aboudi, Ula
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Fluid and Climate Technology.
    Altaie, Kenan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Fluid and Climate Technology.
    Solvärme för krypgrunder2008Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 226. Abouelhoda, Mohamed
    et al.
    Issa, Shady
    Center for Informatics Sciences, Nile University, Giza, Egypt.
    Ghanem, Moustafa
    Tavaxy: integrating Taverna and Galaxy workflows with cloud computing support.2012In: BMC Bioinformatics, ISSN 1471-2105, E-ISSN 1471-2105, Vol. 13Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Over the past decade the workflow system paradigm has evolved as an efficient and user-friendly approach for developing complex bioinformatics applications. Two popular workflow systems that have gained acceptance by the bioinformatics community are Taverna and Galaxy. Each system has a large user-base and supports an ever-growing repository of application workflows. However, workflows developed for one system cannot be imported and executed easily on the other. The lack of interoperability is due to differences in the models of computation, workflow languages, and architectures of both systems. This lack of interoperability limits sharing of workflows between the user communities and leads to duplication of development efforts.

    RESULTS: In this paper, we present Tavaxy, a stand-alone system for creating and executing workflows based on using an extensible set of re-usable workflow patterns. Tavaxy offers a set of new features that simplify and enhance the development of sequence analysis applications: It allows the integration of existing Taverna and Galaxy workflows in a single environment, and supports the use of cloud computing capabilities. The integration of existing Taverna and Galaxy workflows is supported seamlessly at both run-time and design-time levels, based on the concepts of hierarchical workflows and workflow patterns. The use of cloud computing in Tavaxy is flexible, where the users can either instantiate the whole system on the cloud, or delegate the execution of certain sub-workflows to the cloud infrastructure.

    CONCLUSIONS: Tavaxy reduces the workflow development cycle by introducing the use of workflow patterns to simplify workflow creation. It enables the re-use and integration of existing (sub-) workflows from Taverna and Galaxy, and allows the creation of hybrid workflows. Its additional features exploit recent advances in high performance cloud computing to cope with the increasing data size and complexity of analysis.The system can be accessed either through a cloud-enabled web-interface or downloaded and installed to run within the user's local environment. All resources related to Tavaxy are available at http://www.tavaxy.org.

  • 227.
    Aboufazeli, N.
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Production Systems.
    Semere, D.T.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Production Systems.
    Ease of Reconfigurability Index: For Evaluation of the Reconfigurable Machine Tools2012Conference paper (Refereed)
    Abstract [en]

    One of the latest developments in manufacturing systems is reconfigurable manufacturing systems in which reconfigurable machine tools are the heart of such systems. The aim of application of this type of machine tool is having rapid cost-effective responsiveness to changes in new product variants or volume in manufacturing companies because of different interests, needs and desires of customers in global competitive market. The important tools to implement this kind of systems are systematic methodologies and enablers like open architecture controllers, Interface standard and comprehensive and integrated software to make the couple of limited optimized configurations of the machine tool. To choose the best configuration among proposed configuration by the software we need some evaluation methods based on smart chosen criteria to choose the best modular machine tool structure. One of the important points to choose the best configuration is ease of reconfigurability. The aim of this paper is to introduce a flexible and practical index for different products in reconfigurable manufacturing systems. This Index is defined based on two important factors: number of the changeable modules and the complexity of the interfaces including mechanical, informational and power (hydraulic, pneumatic or electrical).Generally the more number of the modules and the more complex interfaces means the more difficult to reconfigure the machine tool structure.

  • 228.
    Aboufazeli, Nasser
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Reconfigurable Machine Tools Design Methodologies and Measuring Reconfigurability for Design Evaluation2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 229.
    Aboutalebi, Ghareman
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Optimering av fackverksstolpar med konisk eller parallell form2005Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 230.
    Abouzari, Sara
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Solid solution strengthening effect on creep strength of austenitic stainless steel2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sanicro 25 is a newly developed austenitic stainless steel, designed for the next generation of Ultrasupercritical coal-fired boilers in electrical power plants. This material is applicable in reheater and superheater tubes, where the material temperature is up to 700

    °C. One of the main strengthening mechanisms in high temperature materials is solid solution strengthening. A combination of this mechanism and precipitation hardening, promotes creep strength of heat resistance materials. The aim of this work was to characterize the effects of solid solution strengthening on creep strength of Sanicro 25.Previous works has been done for effects of phosphorous in copper and also for influence of laves phase on the creep properties of CrMo alloys. The results of these two works are used and the model is adapted to austenitic stainless steel. First a Zero starting state was defined which was Alloy 316H and then the calculation was made for Sanicro 25. Thermodynamic calculations were made using DICTRA and Thermo-Calc. Elastic misfit parameter was determined using ab initio calculations. The results from the simulation in this work indicate that solutes with larger size misfit compare to the parent atoms have better solid solution strengthening effect. A decrease in the creep strength by increasing temperature has been observed which could be attributed to growth of laves phase.

  • 231. Abou-Zleikha, Mohamed
    et al.
    Székely, Eva
    University College Dublin, Ireland.
    Cahill, Peter
    Carson-Berndsen, Julie
    Multi-level exemplar-based duration generation for expressive speech synthesis2012In: Proceedings of Speech Prosody, 2012, Vol. 2012Conference paper (Refereed)
    Abstract [en]

    The generation of duration of speech units from linguistic in- formation, as one component of a prosody model, is consid- ered to be a requirement for natural sounding speech synthesis. This paper investigates the use of a multi-level exemplar-based model for duration generation for the purposes of expressive speech synthesis. The multi-level exemplar-based model has been proposed in the literature as a cognitive model for the pro- duction of duration. The implementation of this model for dura- tion generation for speech synthesis is not straightforward and requires a set of modifications to the model and that the linguis- tically related units and the context of the target units should be taken into consideration. The work presented in this paper implements this model and presents a solution to these issues through the use of prosodic-syntactic correlated data, full con- text information of the input example and corpus exemplars. 

  • 232.
    Abraham, Adonai
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Göranson, Max
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Att tänka utanför arket: En kartläggning över samarbeten som lett till produktinnovationer inom svensk pappers- och massaindustri 2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    During the last decade has the market for printing paper begun to decline. The introduction of the smart phones and tablets quickly became a disturbing factor for the printing paper companies. This has forced the product development in the Swedish pulp and paper companies, to a greater extent, to look at more radical innovations. This requires the exploration of new applications and possibilities for the forest resource, an approach that requires expertise beyond what the companies possess internally.

    This study aims to investigate various forms of collaboration within the Swedish pulp and paper industry to identify factors that have been and are successful for product innovations. The aim has also been to investigate whether there is a change in the character of collaborations in the last 25 years. The participating companies in the study were

    SCA, Södra Cell, Holmen/MoDo, Stora Enso, BillerudKorsnäs, and Rottneros, plus some of their collaboration companies.

    The results show that the forms of collaboration in which the Swedish forest industry cooperate have changed considerably. The industry has begun to seek more cooperation with other industries, while collaboration with competitors has decreased. It seems to have become more important to regulate collaborative agreements, primarily how the intangible resources, like patents, are distributed among the participants in collaborations.

    Another conclusion is that there is a link between collaboration and the success of a firm’s product innovation. Companies are dependent on external knowledge for the success of radical innovations and a broad knowledge base is preferable to best be able to generate product innovations. External knowledge could, for example, help companies increase their understanding of other or new markets and may thus be a way to find new uses for the valuable raw material forest offers.

    Key words: radical innovation, collaboration, Swedish pulp and paper industry

  • 233.
    Abraham, Benjamin
    et al.
    KTH, School of Chemical Science and Engineering (CHE).
    Hultgren, Marcus
    KTH, School of Chemical Science and Engineering (CHE).
    Ibert, Tommie
    KTH, School of Chemical Science and Engineering (CHE).
    Möller, Johan
    KTH, School of Chemical Science and Engineering (CHE).
    Termovåtstyrka i oblekt papper2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The wet strength unbleached paper displays after heat treatment is examined in this thesis in which the authors examine the underlying mechanisms of this phenomena by experiments on differently treated paper. Two wet strength mechanism theories are examined; Lignin working as a resin versus carbonyl bonds being the main driving force behind the wet strength after thermal treatment. The authors find that using oxygen bleaching does not increase the wet strength as it would if carbonyl bonds were the main wet strength drivers, the results thus point towards the resin theory but further corroboration is needed before inference can be drawn.

  • 234.
    Abraham, Jonatan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Strand, Anna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Reseavdrag: En analys av ett arbetsmarknadspolitiskt styrmedel ur ett hållbarhetsperspektiv2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The ability to make tax deductions on travel expenses have been present in Sweden since the late 1920s. The main purpose of the state subsidy has been to improve the mobility in the label market. However, in recent years there has been a heated debate as to if the subsidy is truly socio-economically sustainable or not. The favoritism of car users has also made the matter a question of ecological sustainability.

    The aim of this essay is to analyse and provide general knowledge of the swedish system of deductible travel expenses. The text is divided into four major parts:

    • A litterature review presenting the history of the subsidy, previous research, and the current political debate.
    • A questionnaire survey where the general public’s opinion of tax-deductible travel expenses is examined. 
    • A discussion of possible adjustments of the different parameters of the system, where the most optimal ammendment is chosen
    • An analysis of 3 different scenarios; keeping the current system, using the ammended system obtained in the calibration, and removing the system.

    From the results we could conclude that an ammended system would be noticeably more socio-economically viable and ecologically sustainable, compared with the current system. However, a complete removal of the system would be the most optimal. In addition, the questionnaire surveys results shows that the public is mostly positive to travel deductions. However, it was apparent that the views of many could shift completely, when presenting facts.

  • 235.
    Abrahamson, Lars
    et al.
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Söder, Lennart
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Fast calculation of the dimensioning factors of the railway power supply system2007In: Computational Methods and Experimental Measurements XIII, WIT Press, 2007, Vol. 46, p. 85-95Conference paper (Refereed)
    Abstract [en]

    Because of environmental and economical reasons, in Sweden and the rest of Europe, both personal and goods transports on railway are increasing. Therefore great railway infrastructure investments are expected to come. An important part of this infrastructure is the railway power supply system. Exactly how much, when and where the traffic will increase is not known for sure. This means investment planning for an uncertain future. The more uncertain parameters, such as traffic density and weight of trains, and the further future considered, the greater the inevitable amount of cases that have to be considered. When doing simulations concerning a tremendous amount of cases, each part of the simulation model has to be computationally fast - in real life this means approximations. The two most important issues to estimate given a certain power system configuration, when planning for an electric traction system, are the energy consumption of the and and the train delays that a too weak system would cause. In this paper, some modeling suggestions of the energy consumption and the maximal train velocities are presented. Two linear, and one nonlinear model are presented and compared. The comparisons regard both computer speed and representability. The independent variables of these models are a selection of parameters describing the power system, i.e.: power system technology used on each section, and traffic intensity.

  • 236.
    Abrahamsson, Anna-Carin
    KTH, School of Technology and Health (STH).
    Den fysiska arbetsmiljön i förskolan: utveckling, användning och granskning av en riskbedömningsmodell2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The occupational environment in preschool is becoming increasingly important. Occupational injury statistics show an increased incidence of illness among employees in education, health and care. Before action can be taken to improve the working environment, a careful assessment must be made and an action plan created. To include all possible components requires a comprehensive approach. Mapping of the physical work in Hudiksvall Municipality at all preschools provides a means by which to get an overall picture of risk areas within the preschool staff work environment.

    The aim of this work is to describe how the risk assessment model was developed and used with the ambition that it can be used in other municipalities. The model has been tested in Hudiksvall, on two occasions, in 2005 and 2010. The findings from the survey in 2010 are reported here and a comparison with 2005 is made.

    The risk assessment model is based on a survey with open questions for preschool staff combined with observation and assessment of ergonomics and safety engineer of 11 risk areas within the physical environment of the pre-school.

    The results of the survey give a clear picture of current health risks and can be used as a basis for the development of pre-school activities as well as improved maintenance of the municipal buildings. The results have also been communicated to the individual pre-schools to demonstrate their particular areas of risk.

    The combination of survey and professional assessment of several risk areas has been shown to enable a quick identification of possible causes of illness among pre-school staff. To report both positive and negative environmental factors has been an advantage. The clear method of reporting has facilitated decision-making on what if any actions to take. There is a continuing need to develop this and other instruments for the work environment survey of schools, health and social care.

  • 237.
    Abrahamsson, Cajsa
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Miljöpåverkan, hälsopåverkan och LCC för direktdrivna kontra växellådsdrivna vindkraftverk med avseende på deras innehåll av jordartsmetaller2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Vindkraftverk med olika magnetiseringsmetoder (elektromagneter eller permanentmagneter) och maskindriftstyper (direktdrift eller växellådsdrift) undersöks i denna rapport, gällande användningen av jordartsmetaller i dessa. I första delen av rapporten studeras miljö- och hälsopåverkan från jordartsmetallindustrin i den kinesiska provinsen Baotou. Detta då Baotou står för en stor del av försörjningen av jordartsmetaller till vindkraftverksindustrin. I den andra delen av rapporten undersöks skillnaderna i livscykelkostnader mellan vindkraftverk med olika generator- och maskindriftsystem. Rapporten innehåller informationssökningar om olika aspekter som berör dessa teman såsom exempelvis olika typer av vindkraftverksgeneratorer på marknaden, miljöpåverkan från olika ämnen i jordartsmineraler, återvinning av jordartsmetaller och processen från jordartsmineral till permanent-magnet. Informationen är främst inhämtad från vindkraftverkstillverkare, tekniska rapporter och artiklar.

    I miljö- och hälsoanalysen blev slutsatsen att den negativa påverkan från jordartsmetallindustrin i Kina var för omfattande för att användningen av jordartsmetaller skulle rättfärdigas ur ett etiskt och miljömässigt perspektiv. Gruvdriften och bearbetningen av jordartsmetaller har lett till stora utsläpp av skadliga ämnen, såsom exempelvis tungmetaller och radioaktivt avfall, i provinsen Baotou. Dessa har gett allvarliga negativa konsekvenser för djur, människor och växtlighet.

    Livscykelkostnaderna för vindkraftverk med olika generatorsystem beräknades med hjälp av LCC-metoden. Slutsatsen blev att det i dagsläget inte skiljde så mycket kostnadsmässigt i valet av maskindrifttyp eller magnetiseringsmetod. Enligt beräkningar ledde användningen av permanent-magneter inte till några ekonomiska fördelar. Istället var det kostnadsförhandlingar och osäkerhet i indata som gav de största kostnadsskillnaderna. Drift och underhållskostnaderna stod för de definitivt största utgifterna och investeringskostnaderna till generatorsystemen för de näststörsta utgifterna.

  • 238.
    Abrahamsson, Cajsa
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Carlberg, Marcus
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Studie i att ersätta kärnkraftsreaktor med biobränslealternativ2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report contains a study of replacing nuclear power with biofuel. The nuclear plant, OKG north of Oskarshamn in Sweden has been chosen and an extensive literature study about the nuclear plant has been implemented. The main aspect of this report is the availability of biofuels and whether it would be economically sustainable. Sweden’s most common biofuels are examined with regard to scope of use and potential. In the economic analysis the investments and variable costs are investigated. To conclude the work the carbon emissions due to transports of biofuel are examined.The literature study on biofuels were discussed and resulted in that the project was defined towards woodchips. Due to several aspects the project focused on replacing OKG's oldest reactor O1. Furthermore the project focused on just electricity production and combustion with CFB-boilers. Due to the Economic analysis the plant will not be profitable in the current situation. The plant profitability was examined by the net present value method. With 2011s prices, a discount rate of 6 % and an initial investment of 5.78 billion SEK the economic analysis yielded a net present value of -3.53 billion SEK. A higher price of electricity or an alternate income, for example by district heating, would be required to make the plant profitable. It would require a price of electricity of 0.55 SEK/kWh to make the plant profitable. The carbon emission due to transports of biofuel for the new plant was estimated to 6 gram/kWh and this emission was higher than that for the reactor O1.

  • 239.
    Abrahamsson, Erik
    KTH, School of Biotechnology (BIO).
    Changing or improving the enantioselectivity of ω-transaminase towards (R)-amines, utilizing a semi-rational design approach2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis gives a brief insight on how protein engineering is made with ω-Transaminases - enzymes that are used to create chiral amines which are included in many pharmaceuticals, fine chemicals and agrochemicals - in order to find ω-Transaminase variants that have potential for scale up in industrial processes.

    Several ways to produce (S)-amines with ω-Transaminases exist today as most characterized ω-Transaminases are (S)-selective. The (R)-selective ω-Transaminases are in the other hand rare and in 2003, only 1 (R)-selective ω-Transaminases was known. In 2012, the group of Svedendahl Humble et al. to change the enantioselectivity for the substrate 2-aminotetralin from E = 3.9 (S) to E = 63 (R) by introducing two poiny mutations (F88A/A231F) in the active site of Chromobacterium violaceum ω-Transaminase.

    By using the same variant (F88A/A231F) as a starting template, two new residues in the active site were targeted for site directed mutagenesis that hopefully would give variatns with increased E-caalue for (R)-2-aminotetralin or with changed enantiopreference, frpm (S) to (R), for other stubstrates.

    This report covers most of the steps, starting from the rational design of the active site and ends up with screening and kinetics of the possible hits using one template substrate, 1-aminotetralin.

  • 240.
    Abrahamsson, Erik
    et al.
    KTH, School of Engineering Sciences (SCI).
    Svensson, Anton
    Design och konstruktion av experimentrigg: För planande skrov i lugnt vatten2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den här rapporten är ett kandidatsexamensarbete vid Kungliga Tekniska Högskolan,KTH, för institutionen för Marina System. Arbetet utfördes på campus i Stockholm och experiment utfördes på GIH-Badet. Kandidatsexamensarbetet genomfördes mellan Jan 2016-Juni2016.Författarna skulle vilja ge ett stort tack till handledaren Mikael Razola för bra vägledning och stöd genom hela projektet där han hela tiden sett till attprojektet rört sig framåt och i rätt riktning. Hans feedback och snabba svar närfrågor uppstått samt hans input vid möten uppskattades enormt. Karl Garme tackas också för att han delade med sig av sin erfarenhet av projektplaneringoch också såg till att projektet rörde sig framåt med sitt övergripande ansvar för kandidatsexamensarbetet. Alla medstudenter som deltagit under kursens gång vill även tackas för feedback och diskussioner under seminarierna.Ett stort tack vill också ges till Björn Magnusson som hjälpte till med CNCfräsning av modellen och Monica Norrby för hennes tid med tips och tricks i labbet vid tillverkning av modellen.

  • 241.
    Abrahamsson, Felix
    KTH, School of Engineering Sciences (SCI).
    Microscopic Models for Trac Dynamics2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As the volume of vehicular trac has been increasing ever since its

    advent in the early 20th century, trac dynamics has become a popu-

    lar topic of study amongst physicists and mathematicians. This paper

    aims to explain di erent ways of modeling and simulating trac and

    trac dynamics. In general, modeling of trac can be divided into

    two types of models, microscopic and macroscopic. In this paper, pri-

    mary focus is on microscopic models. Examples are shown on how

    to implement simulations of so called car-following models as well as

    models based on cellular automata. Certain problems and scenarios

    regarding trac are studied as well. These include how to eciently

    distribute a roadblock, how to set the green/red time periods of a traf-

    c light in order to achieve a high trac ow or a low vehicle density,

    and how trac ow can be maximized with respect to density or other

    parameters. Results show that simulations using cellular automata

    models generally compute faster than simulations using car-following

    models. However, the results obtained from cellular automata models

    tend to be more dicult to interpret and apply to real-world sce-

    narios. A high level of stochasticity in the cellular automata models

    was also found to be necessary for the models to give applicable re-

    sults. Car-following models, on the other hand, were found to have

    the advantage of being more deterministic.

  • 242.
    Abrahamsson, Felix
    KTH, School of Engineering Sciences (SCI).
    Microscopic Models for Trac Dynamics2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As the volume of vehicular trac has been increasing ever since its

    advent in the early 20th century, trac dynamics has become a popu-

    lar topic of study amongst physicists and mathematicians. This paper

    aims to explain di erent ways of modeling and simulating trac and

    trac dynamics. In general, modeling of trac can be divided into

    two types of models, microscopic and macroscopic. In this paper, pri-

    mary focus is on microscopic models. Examples are shown on how

    to implement simulations of so called car-following models as well as

    models based on cellular automata. Certain problems and scenarios

    regarding trac are studied as well. These include how to eciently

    distribute a roadblock, how to set the green/red time periods of a traf-

    c light in order to achieve a high trac ow or a low vehicle density,

    and how trac ow can be maximized with respect to density or other

    parameters. Results show that simulations using cellular automata

    models generally compute faster than simulations using car-following

    models. However, the results obtained from cellular automata models

    tend to be more dicult to interpret and apply to real-world sce-

    narios. A high level of stochasticity in the cellular automata models

    was also found to be necessary for the models to give applicable re-

    sults. Car-following models, on the other hand, were found to have

    the advantage of being more deterministic.

  • 243.
    Abrahamsson, Johan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Danmo, Johan
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    The Stabilizing Spoon: Self-stabilizing utensil to help people withimpaired motor skills2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The technology for assisting people who are functionallychallenged has improved over the recent decades. With today’stechnology, people with Parkinson’s disease can, witha device on their wrist, be able to draw pictures. Humanlimbs lost due to accidents can be replaced with bionic limbsand with help from smartphones, blind people can by audiobe informed what kind of object that appear in frontof them. These are a few examples where technology haseased everyday life for people with impaired functionality.The purpose of this thesis is to analyze how an Arduino microcontrollercan be utilized to help people with impairedmotor skills during their eating process. A prototype of astabilizing spoon was constructed to work under real circumstancesand intended to be a complement for peoplewho are in need of assistance during their eating process.To make this possible, a sensor with gyroscopes combinedwith accelerometers was used to identify which directionthe device’s handle was being tilted, as well as how fastits position was changed. Two servo motors were placedorthogonally to each other to establish a system of two degreesof freedom. With this setup, the spoon was intendedto maintain its spoon bowl in a horizontal position. Experimentalresults of the spoon showed promising performancewith some limitations.

  • 244.
    Abrahamsson, Johanna
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies.
    Vild natur: Värden, attityder och associationer2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Modern humans are considered to have lost connection to nature and actions to reduce the separation between man and nature has been demanded. Green areas are often valued from a broad perspective and few studies have investigated the specific nature of the wild habitat. There also seem to be definitive problems and conflicts regarding the concept of "wild nature". The purpose of this report is to identify the specific values of wild nature ​​and to investigate what the concept really can include. Another purpose is to investigate attitudes and associations to wild nature and how wild nature is being worked on in planning.

    A literature study has been used as the primary method. The literature study has been supplemented with a minor case study including a documentary study, interviews and questionnaires.

    The conclusion is that wild nature offers values ​​of ecological, educational and experiential character. The ecological value is that wild nature allows biodiversity. The educational value includes aspects that help strengthen the connection to nature, which may lead to changed environmental behavior. Wild nature also has values ​​that concerns for example the experience of spiritual and reflective emotions, contributing to stress reduction and increased well-being. Moreover, wild nature is associated with large areas unaffected by humans. The same approaches are in the planning process, and the experience of wild nature is often evaluated from an ecological perspective. This means that the potential of green spaces that does not fit into the traditional image is not taken advantage of. Wild nature can also be defined based on the experience qualities related to wildness. A development towards such an approach could mean that the specific nature of the wild nature is taken advantage of. This could contribute to the increased well-being of the residents, but in the long term, a more sustainable society.

  • 245.
    Abrahamsson, Lars
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Optimal Railroad Power Supply System Operation and Design: Detailed system studies, and aggregated investment models2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Railway power supply systems (RPSSs) differ mainly from public power systems from that the loads are moving. These moving loads are motoring trains. Trains can also be regenerating when braking and are then power sources. These loads consume comparatively much power, causing substantial voltage drops, not rarely so big that the loads are reduced. By practical reasons most RPSSs are single-phase AC or DC. Three-phase public grid power is either converted into single-phase for feeding the railway or the RPSS is compartmentalized into separate sections fed individually from alternating phase-pairs of the public grid. The latter is done in order not to overload any public grid phase unnecessarily much.

    This thesis summarizes various ways of optimally operating or designing the railway power supply system. The thesis focuses on converter-fed railways for the reasons that they are more controllable, and also has a higher potential for the future. This is also motivated in a literature-reviewing based paper arguing for the converter usage potential. Moreover, converters of some kind have to be used when the RPSS uses DC or different AC frequency than the public grid.

    The optimal operation part of this thesis is mainly about the optimal power flow controls and unit commitments of railway converter stations in HVDC-fed RPSSs. The models are easily generalized to different feeding, and they cope with regenerative braking. This part considers MINLP (mixed integer nonlinear programming) problems, and the main part of the problem is non-convex nonlinear. The concept is presented in one paper. The subject of how to model the problem formulations have been treated fully in one paper.

    The thesis also includes a conference article and a manuscript for an idea including the entire electric train driving strategy in an optimization problem considering power system and mechanical couplings over time. The latter concept is a generalized TPSS (Train Power Systems Simulator), aiming for more detailed studies, whereas TPSS is mainly for dimensioning studies. The above optimal power flow models may be implemented in the entire electric train driving strategy model.

    The optimal design part of this thesis includes two aggregation models for describing reduction in train traffic performance. The first one presented in a journal, and the second one, adapted more useful with different simulation results was presented at a conference. It also includes an early model for optimal railway power converter placements.

    The conclusions to be made are that the potential for energy savings by better operation of the railway power system is great. Another conclusion is that investment planning models for railway power systems have a high development potential. RPSS planning models are computationally more attractive, when aggregating power system and train traffic details.

  • 246.
    Abrahamsson, Lars
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Railway Power Supply Models and Methods for Long-term Investment Analysis2008Licentiate thesis, monograph (Other scientific)
    Abstract [en]

    The aim of the project is to suggest an investment planning programwhere the welfare of the society is to be maximized. In order to beable to decide on a wise investment plan, one needs to know theconsequences of different choices of power system configurations.Therefore the impacts of different future traffic demands are ofinterest for a railway power system owner.Since investments are supposed to last a long time, their futureusage has to be considered. Moreover, the lead times of investmentscan be of considerable duration lengths. Because of the uncertaintyof the future, deterministic case studies might not be suitable andthen a large number of outcomes are to be studied, probable outcomesas well as outcomes with a high level of impact.In order to be able to make a valid long-term investment analysis ofthe railway power supply system, one needs to use proper railwaypower supply models and methods. The aim of this thesis is topresent a stable modeling and methodological basis for the cominginvestment planning phase of this PhD research project. The focus isset on studying the consequences of a railway power supply systemwhich is too weak.The thesis contains an overview of models of some electrical andmechanical relations important for electric traction systems. Someof these models are further developed, and some are modified forimproved computational properties. A flexible electric tractionsystem simulator based on the above mentioned models has beendeveloped and the applied methods and resulting abilities arepresented.The main scientific contribution of this thesis is that a fast andapproximative neural network model, which calculates some importantaggregated results of the interaction between the railway powersystem and the train traffic, has been developed. This approximativemodel was developed in order to reduce computation times. Reductionof computation times is very important when a huge number ofoutcomes are studied. A complete simulation of a train power systemin operation takes a long time, often not less than about a tenth ofthe simulated traffic time. The neural network is trained with someselected aggregated results extracted from a wide set of railwayoperation simulation cases. The choices of network inputs andoutputs are motivated in the thesis. The performance of thesimulator as well as the approximator are visualized in casestudies.

  • 247.
    Abrahamsson, Lars
    et al.
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Kjellqvist, Tommy
    Elekt Konsult AB, Kraftelektronik, Sweden.
    Östlund, Stefan
    KTH, School of Electrical Engineering (EES), Electrical Energy Conversion.
    High-voltage DC-feeder solution for electric railways2012In: IET Power Electronics, ISSN 1755-4535, E-ISSN 1755-4543, Vol. 5, no 9, p. 1776-1784Article in journal (Refereed)
    Abstract [en]

    For AC railway power supply systems with a different frequency than the public grid, high-voltage AC transmission lines are common, connected to the catenary by transformers. This study suggests an alternative design based on an high-voltage DC (HVDC)-feeder, which is connected to the catenary by converters. Such an HVDC line would also be appropriate for DC-fed railways and AC-fed railways working at a public-grid frequency. The converter stations between the public grid and the HVDCfeeder can be sparsely distributed, not denser than on 100 km distances, whereas the converters connecting the HVDC-feeder to the catenary are distributed denser. Their ratings can be lower than present-day substation transformers or converters, since the power flows can be fully controlled. Despite a relatively low-power rating, the proposed converters can be highly efficient because of the use of medium frequency technology. The proposed feeding system results in lower material usage, lower losses and higher controllability compared with the present solutions. Simulations of the proposed solution show clear advantages regarding transmission losses and voltages compared with conventional systems, especially for cases with weak feeding, and when there are substantial amounts of regeneration from the trains.

  • 248.
    Abrahamsson, Lars
    et al.
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Kjellqvist, Tommy
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Östlund, Stefan
    KTH, School of Electrical Engineering (EES), Electrical Energy Conversion.
    HVDC Feeder Solution for Electric Railways2012In: IET Power Electronics, ISSN 1755-4535, E-ISSN 1755-4543Article in journal (Refereed)
    Abstract [en]

    The railway power supply systems in many sparsely populated countries are relatively weak. Weak railway power supply systems causes problems with power quality, voltage drops, and high transmission losses.

    For AC railway power supply systems with a different frequency than the public grid, high-voltage AC (HVAC) transmission lines are common, connected to the catenary by transformers.

    In this paper an alternative design based on an HVDC feeder is suggested. The HVDC feeder is connected to the catenary by converters. Such an HVDC line would also be appropriate for DC-fed railways and AC-fed railways working at public frequency. The converter stations between the public grid and the HVDC feeder can be sparsely distributed, in the range of 100 km or more, whereas the converters connecting the HVDC feeder to the catenary are distributed with a much closer spacing. Their ratings can be lower than substation transformers or electro-mechanical converters, since the power flow can be fully controlled.

    Despite a relatively low power rating, the proposed converters can be highly efficient due to the use of medium frequency technology. The HVDC-based feeding system results in lower material usage, lower losses and higher controllability compared to present solutions.

    Simulations of the proposed solution show clear advantages regarding transmission losses and voltages compared to conventional systems, especially for cases with long distances between feeding points to the catenary, and when there are substantial amounts of regeneration from the trains.

  • 249.
    Abrahamsson, Lars
    et al.
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Schütte, Thorsten
    Östlund, Stefan
    KTH, School of Electrical Engineering (EES), Electrical Energy Conversion.
    Use of converters for feeding of AC railways for all frequencies2012In: Energy for Sustainable Development, ISSN 0973-0826, Vol. 16, no 3, p. 368-378Article in journal (Refereed)
    Abstract [en]

    Railways are the most energy-efficient land-based mode of transport, and electrification is the most energy-efficient way to power the trains. There are many existing solutions to supply the trains with electricity. Regardless of which particular technology is chosen, it is beneficial to interconnect the public power grids to grids supplying power to the railways. This paper shows that the most efficient, flexible, and gentle-for-the-public-grid way of doing that is through power electronic-based power converters. Converters offer great benefits regardless of whether the overhead contact lines are of DC-type or AC type, and regardless of the AC grid frequency. This paper presents neither new theory nor new experimental results. Based on already available information, this paper presents logical arguments leading to this conclusion from collected facts. Over time what used to be advanced and high-cost equipment earlier can nowadays be purchased at reasonable cost. It is obvious that for most electrically-fed railways, the use of modern power converters is attractive. Where the individual trains are high consumers of energy, the railway gradients are substantial, and the public grids feeding the railway are weak, the use of converters would be technically desirable, if not necessary for electrification.It is expected that more high-speed railways will be built, and more existing railways will be electrified in the foreseeable future. This paper could provide some insights to infrastructure owners and decision makers in railway administrations about value additions that converter-fed electric railways would provide.

  • 250.
    Abrahamsson, Lars
    et al.
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Skogberg, Ronny
    Östlund, Stefan
    KTH, School of Electrical Engineering (EES), Electrical Energy Conversion.
    Lagos, Mario
    Söder, Lennart
    KTH, School of Electrical Engineering (EES), Electric Power Systems.
    Identifying electrically infeasible traffic scenarios on the iron ore line: Applied on the present-day system, converter station outages, and optimal locomotive reactive power strategies2015In: PROCEEDINGS OF THE ASME JOINT RAIL CONFERENCE, 2015, AMER SOC MECHANICAL ENGINEERS , 2015Conference paper (Refereed)
    Abstract [en]

    This paper presents the main findings of a Master's Thesis project carried out in cooperation between Transrail and Royal Institute of Technology (KTH). The main objective was to create a plugin for checking the electric power system feasibility of a train traffic plan with an associated driving strategy created by TRAINS a Transrail software product. Secondary aims with the project was to study power system feasibilities during converter station outages, and to which extent optimal operation of the locomotive converters' reactive power assure power system feasibilities. In the developed optimal reactive power strategies, the main priority was to fulfill the desired traffic plans, whereas the secondary priority was to minimize railway power system power consumption. The case studies are applied on representative traffic scenarios and power system models representing the northern part of the Iron Ore line in Northern Sweden. The focus of the study is set on the IORE locomotives and the iron ore trains they haul. The optimized locomotive reactive power regards IORE, so also the investigated power system feasibilities of the traffic plans.

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