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  • An, Jihyun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Feminist Futures: Futures studies through the lens of feminist epistemologies2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study explores how futures studies could engage with critical feminist perspectives in an intrinsic manner and what feminist futures might mean. The study brings attention to the less discussed subject of epistemological basis in futures studies. Literature study and semi-structured interviews with practitioners and researchers working with feminist approaches in the fields related to futures development was deployed. I’ve analyzed Wendell Bell’s discussion on epistemological foundation of futures studies from feminist epistemological perspective, and have suggested the potential of feminist epistemology of situated knowledges and partial objectivity for futures studies. Based on the findings from the semi-structured interviews, an alternative feminist scenario set in Swedish society in the year of 2050 in the format of a fiction is presented with the aim to provide a detailed and situated narrative of political and daily lives in feminist futures. The feminist futures scenario should not be understood as the singular feminist future suggested for implementation. The intention is to demonstrate how the visionary dimensions of feminist studies could be articulated in various forms of futures studies, and to open up space for rich debates on envisioning feminist futures. 

  • Lewenhaupt, Adam
    et al.
    KTH, School of Industrial Engineering and Management (ITM).
    Brismar, Emil
    KTH, School of Industrial Engineering and Management (ITM).
    The impact of corpus choice in domain specific knowledge representation2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Recent advents in the machine learning community, driven by larger

    datasets and novel algorithmic approaches to deep reinforcement learning,

    reward the use of large datasets. In this thesis, we examine whether

    dataset size has a signicant impact on the recall quality in a very specic

    knowledge domain. We compare a large corpus extracted from Wikipedia

    to smaller ones from Stackoverow and evaluate their representational

    quality of niche computer science knowledge. We show that a smaller

    dataset with high-quality data points greatly outperform a larger one, even

    though the smaller is a subset of the latter. This implicates that corpus

    choice is highly relevant for NLP-applications aimed toward complex and

    specic knowledge representations.

  • Chivi, Daniel
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Östling Gran, Joakim
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Administration av API-drivna enheter och tjänster för slutanvändare: En fallstudie av API-tjänster2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nowadays people tend to use services and appliances that are managed seperately. This thesis examines the possibility of connecting different services into one main web application to faciliate communication between these services.

    A Great Thing have embraced the need of connecting applications to a single device and therefore, wants to create a web application integrated with the use of agents. These agents are built to manage the events a user request. For example ”Play a song at a specific time”.

    The methodology applied has partly been a case study and partly user-based methods in form of a survery and a user test. Further research was conducted on communication between service API:s and the necessary parameters that exchange data. Finally, the developed prototype was evaluated according to some usability guidelines.

    The thesis’s results are presented in the form of a web prototype focused on usability, implementation of APIs, user test of actual users and statistics of demanded services. In addition, a market research has been conducted to highlight economic benefits through API distribution. The conclusion is drawn that it is possible to link API:s and their services to achieve a user-friendly interface and how to use different parameters in an efficient way. Furthermore, the hope is that external readers will understand how the connection between API:s works in a structured and informative approach. Also how different technical methods for usability can be applied in construction of prototypes.

  • Dang, Julia
    et al.
    KTH, School of Computer Science and Communication (CSC).
    Gjordeni, Kejsi
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.).
    Introduktion till text- och bildbaserad programmering till förstagångsanvändare2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The objective of this thesis is to introduce textual and visual based programming to first time users and evaluate how they are perceived, by performing literature research and conducting field studies at Grimstaskolan.By dividing a class of students in two test groups, each were introduced to textual language Python and visual language Scratch respectively. The initial response showed visual based programming as a more fun and motivating method of programming for a continued interest in learning. However, it was subsequently noted that visual programming itself was very distracting from the actual assignments. Despite Python being considered less motivating, the actual program was not a source of distraction in the aspect as Scratch was. What can be concluded is that Scratch is a good introductory language to promote systematic reasoning. It may also motivate children more to pursue programming, to then later have the ability to visualize the processes in a text based language such as Python. There are many different methods of practical implementation of computational programming, as of which cross-curricular programming and having it as a separate course are notably the two main possibilities, both of which are arguably preferable. As a recommendation that can be concluded for The National Agency for Education (Skolverket), a combination of multiple methods could be more appropriate, but should be more extensively studied.

  • Naciri, Nacer
    KTH, School of Engineering Sciences (SCI), Physics.
    Validation of on-board algorithms for SVOM satellite payload management2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • Public defence: 2018-04-12 10:00 F3, Stockholm
    Li, Wei
    KTH, School of Electrical Engineering and Computer Science (EECS), Electric Power and Energy Systems.
    PMU-based State Estimation for Hybrid AC and DC Grids2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Power system state estimation plays key role in the energy management systems(EMS) of providing the best estimates of the electrical variables in the grid that arefurther used in functions such as contingency analysis, automatic generation control,dispatch, and others. The invention of phasor measurement units (PMUs) takes thepower system operation and control into a new era, where PMUs’ high reportingrate and synchronization characteristics allow the development of new wide-areamonitoring, protection, and control (WAMPAC) application to enhance the grid’sresiliency. In addition, the large number of PMU installation allows the PMU-onlystate estimation, which is ready to leap forward today’s approach which is based onconventional measurements.At the same time, high voltage direct current (HVDC) techniques enable totransmit electric power over long distance and between different power systems,which have become a popular choice for connecting variable renewable energy sourcesin distant locations. HVDCs together with another type of power electronic-baseddevices, flexible AC transmission system (FACTS), have proven to successfullyenhance controllability and increase power transfer capability on a long-term costeffectivebasis. With the extensive integration of FACTS and HVDC transmissiontechniques, the present AC networks will merge, resulting in large-scale hybrid ACand DC networks. Consequently, power system state estimators need to considerDC grids/components into their network models and upgrade their estimationalgorithms.This thesis aims to develop a paradigm of using PMU data to solve stateestimations for hybrid AC/DC grids. It contains two aspects: (i) formulating thestate estimation problem and selecting a suitable state estimation algorithm; (ii)developing corresponding models, particularly for HVDCs and FACTS.This work starts by developing a linear power system model and applying thelinear weighted least squares (WLS) algorithm for estimation solution. Linear networkmodels for the AC transmission network and classic HVDC links are developed. Thislinear scheme simplifies the nonlinearities of the typical power flow network modelused in the conventional state estimations and has an explicit closed-form solution.However, as the states are voltage and current phasors in rectangular coordinates,phasor angle is not an explicit state in the modeling and estimation process. Thisalso limits the linear estimators’ ability to deal with the corrupt angle measurementsresulting from timing errors or GPS spoofing. Additionally, it is cumbersome toselect state variables for an inherently nonlinear network model, e.g., classic HVDClink, when trying to fulfill its linear formulation requirement.In contrast, it is more natural to use PMU measurements in polar coordinatesbecause they can provide an explicit state measurement set to be directly used inthe modeling and estimation process without form changes, and more importantly,it allows detection and correction for angle bias which emerges due to imperfectsynchronization or incorrect time-tagging by PMUs. To this end, the state estimationproblem needs to be formulated as a nonlinear one and the nonlinear WLS is applied for solution. We propose a novel measurement model for PMU-based state estimationwhich separates the errors due to modeling uncertainty and measurement noise sothat different weights can be assigned to them separately. In addition, nonlinearnetwork models for AC transmission network, classic HVDC link, voltage sourceconverter (VSC)-HVDC, and FACTS are developed and validated via simulation.The aforementioned linear/nonlinear modeling and estimation schemes belongto static state estimator category. They perform adequately when the system isunder steady-state or quasi-steady state, but less satisfactorily when the system isunder large dynamic changes and the power electronic devices react to these changes.Testing results indicate that additional modeling details need to be included toobtain higher accuracy during system dynamics involving fast responses from powerelectronics. Therefore, we propose a pseudo-dynamic modeling approach that canimprove estimation accuracy during transients without significantly increasing theestimation’s computational burden. To illustrate this approach, the pseudo-dynamicnetwork models for the static synchronous compensator (STATCOM), as an exampleof a FACTS device, and the VSC-HVDC link are developed and tested.Throughout this thesis, WLS is the main state estimation algorithm. It requiresa proper weight quantification which has not been subject to a sufficient attentionin literature. In the last part of thesis, we propose two approaches to quantify PMUmeasurement weights: off-line simulation and hardware-in-the-loop (HIL) simulation.The findings we conclude from these two approaches will provide better guidancefor selecting proper weights for power system state estimation.

  • Public defence: 2018-04-20 13:30 Architecture School, A108, Stockholm
    Karami, Sepideh
    KTH, School of Architecture and the Built Environment (ABE), Architecture, Critical Studies in Architecture.
    Interruption: Writing a Dissident Architecture2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Interruption: Writing a Dissident Architecture makes a contribution to the fields of writing architecture and dissident architecture. Concerned with developing an ethos of criticality from within, it presents a series of performative writing experiments that are situated in politically charged architectural sites, from public spaces, to institutions, to domestic spaces. My aim is to ask how a dissident architecture could be produced through the practice of writing, specifically by offering an account of the performative acts of various characters who are introduced in the thesis, and who critically inhabit existing architectural sites, interrupt the spatial power relations of those sites, and who thereby construct 'performing grounds'.

    Writing architecture is developed in this thesis not as writing about architecture, but aims instead to write it, to make it. Writing dissident architecture writes with multiple voices, with many authors, not all of whom are welcomed. It offers significant approaches to a political and critical understanding of architecture. Where architecture in this thesis is understood both as a material structure and as a disciplinary framework in which power can become oppressive, writing architecture, on the other hand, is developed as a ‘minor’ practice that can act upon existing sites, interrupting their ‘major’ power relations. Interruption, developed as a tactic, is what activates architecture to become a performing ground for the act of dissidence. 

    Formulated as a journey the three main parts of the thesis deal with three interrupting tactics: Pause, Cut and Fo(o)l+d, which are applied in relation to three different kinds of political site: 1) spaces of appearance or the spectacle; 2) disciplined spaces understood as sites of impossibility; 3) domestic spaces as displaced loci of subversive political actions. The Pause uses stillness and refusal as a mode of interruption. The Cut interrupts the material and structural continuity of established institutions and creates cracks in those systems. The Fo(o)l+d interrupts surveillance and control by folding in and out of private and public spaces. By introducing a quasi-fictional character to each site, who performs through one of the three tactics of interruption, a performing ground is constructed. Writing architecture forwards this journey across specific sites through which the figure of the dissident emerges.






  • Tang, Zihao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Development and Evaluation of Virtual Reality Heart Rate Variability Biofeedback Application2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: Reduced heart rate variability is an important factor in evaluation of autonomic nervous system and diseases. Resonance frequency breathing is a non-invasive and effective training method for increasing heart rate variability. Turing this breathing exercise into a video game is an efficient way to reduce training time and vapidity. Though there has been a successful implementation in 3D game, the influence of virtue reality technology application and interaction elements still need to be explored. Objective: The main objective is to build and evaluate the virtue reality game. Applying appropriate game design and interaction elements will also be discussed. The correct and efficient training should be ensured. Also, recognizing the relationship between game elements and efficiency is also included in the task. By evaluating the impact in heart rate variability biofeedback, the understanding of breathing training game design will be broadened and deepened. Methods: A 3D virtue reality running game is designed with biofeedback framework. Development process is conducted in a user-centred way with interface test. The summative evaluation will be performed 10 participants in a controlled setting. (participant age and health state) Each participant will fill a post-test questionnaire about game experience. The sensor data will be stored on local device. Qualitative analyse of data will be done. Results: VR environment game has shown more significant effects in helping increase heart rate variability than normal game (P<0.05). Both modes have shown more than 50% increase in standard deviation of heart rate variability. A high immersion and positive effects along was reported by a Game Experience Questionnaire. Conclusion: The results have shown that the VR game has the potential to help increase HRV via the resonance breathing training. The game can also allow long-term study by increasing the motivation of participants. Evaluation with GEQ are presented, which will give insights about the usability of this game. Additionally, the new tracks for future study have been explored.

  • Burroughs, Brady
    KTH, School of Architecture and the Built Environment (ABE).
    What’s Love Got To Do With It?: Adopting a love ethic to perform the critical differently2018In: trans 32: Liebe, p. 179-185Article in journal (Other (popular science, discussion, etc.))
    Abstract [en]

    You must understand though the criticism at hand

    Makes my pulse react

    That it's only the thrill of critique gone ill

    When opposition’s a fact

    It's judgmental

    Only habitual

    Lest you try to ignore that it means more than that ooo

    What's love got to do, got to do with it…

  • Public defence: 2018-03-28 09:00 F3, stockholm
    Ekane, Nelson
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies. KTH, Stockholm.
    ‘Making Sanitation Happen’: An Enquiry into Multi-Level Sanitation Governance2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The importance of sanitation for human health and development is undisputed. Sanitation is now high on the international development agenda and has become a salient issue in most developing countries, Rwanda and Uganda being no exception. However, there are still shortcomings as regards ‘making sanitation happen’ on the ground. The basic institutional environment and the right governance structures are yet to be fully put in place. This is even more important in the new modes of governance wherein increasing numbers of public, private, and philanthropic actors at different levels of society are involved in sanitation provision and hygiene promotion driven largely by global goals and international development agendas. This has engendered top-down pressure to meet prescribed targets which in most cases miss the complexity of context, distort service priorities, and in some cases compromise sustainability.

    This thesis disentangles how sanitation policies are articulated at multiple levels of governance and among various actors in the sector, and eventually translate into investment and behaviour change at the community and household levels. This is done by examining sanitation governance structures in Rwanda and Uganda. Specific emphasis is placed on the actors and actions at national, sub-national, community and household levels.

    Drawing on multi-level governance as a conceptual framework, qualitative analysis of policy objectives and choices, and quantitative investigations of what motivates hygiene behaviour change at the community and individual levels, this cross-national comparative study is a novel attempt to decipher the complexity surrounding sanitation and to show ‘what makes sanitation happen’.

    The insights of this research build on different strands of the literature but most importantly they contribute to the debate in the sanitation sector on what works on the ground, why and where.


  • Leijon, Anna Mikaelsdotter
    KTH, School of Industrial Engineering and Management (ITM).
    The Right Price - At What Cost?: A Multi-industry Approach in the Context of Technological Advancement2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The business climate is undergoing a transformation and managers are faced with several challenges, not the least of which is related to pricing strategy. With an increased transparency in the market as well as anincreased competitive pressure, and with more sophisticated and well-informed consumers, retail businesses find it hard to navigate the pricing jungle. At the same time, the conventional wisdom in the field of pricing and the theoretical models on the topic, originate from a time long before the digitalization. Old models are not a problem in itself, but when there are new forces in the pricing ecosystem, driven by technological advancement, an assessment of the incumbent models is in the best interest of both businesses and academia. The reason for this is that, the use of old models that rely on inaccurate assumptions may impact businesses’ prioritizing of resources or their overall business strategy. In addition, researchers might be distracted and the research field disrupted. Thus, the purpose of this study is to discuss whether or not there are additional dimensions in pricing strategy that are not covered by the incumbent pricing models. Here, dimensions refer to the key components of businesses’ strategic decision making in regards to pricing. This thesis examines pricing models in today’s business context in order to answer the research question: “Are there additional dimensions of the empirical reality of pricing strategy that are not covered by the incumbent pricing models?” The research question has been studied qualitatively through a literature review, a pilot study and twelve case studies, where the pilot study had the purpose of exploring the depth, whereas the multiple case studies focused on the breadth, of pricing strategies. The case studies cover businesses in different retail industries and of different sizes, namely the industries of Clothing & Accessories, Daily Goods, Furniture and Toys & Tools, and of the following sizes: micro, small, medium and large. The empirical data has mainly been gathered by conducting interviews with production, sales and management personnel at the case businesses. The data has been structured, reduced and analysed with the help of a framework of analysis that has been developed throughout the pilot study. The results of this study lean on previous research and a main divider in pricing strategies has been identified as businesses use either a data-driven or an intuition-driven approach in their strategic work with pricing. As such, it is proposed that the division of pricing strategies need to be acknowledged, since the separate methodological approaches may lead to different results, while implying different costs, resources and required knowledge. Furthermore, the division may form a basis for competitive advantage, be extended to other areas of strategic management and become clearer, since the adoption of technology and its impact will increase in the future. As a result, in the future of pricing, they key is going to be to account for both the strategic perspectives and the methodological approaches in the strategic decision making process of pricing.

  • Ödling, David
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Optimization and Systems Theory.
    A metaheuristic for vehicle routing problems based on reinforcement learning2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The vehicle routing problem is an old and well-studied problem that arise in last mile logistics. The rapid increase of e-commerce, in particular with an increasing the demand for time scheduled home deliveries on the customer’s terms, is making the problem ever more relevant. By minimizing the cost and environmental impact, we have the setting for mathematical problem called the vehicle routing problem with time windows.

    Since the problem is NP-Hard, heuristic methods are often used. In practice, they work very well and typically offer a good tradeoff between speed and quality. However, since the heuristics are often tailormade to fit the needs of the underlying problem, no known algorithm dominates the other on all problems.

    One way to overcome the need for specialization is to produce heuristics that are adaptive. In this thesis, an offline learning method is proposed to generate an adaptive heuristic using local search heuristics and reinforcement learning.

    The reinforcement learning agents explored in this thesis are situated in both discrete and continuous state representations. Common to all state spaces are that they are inspired by human-crafted reference models where the last action and the result of that action define the state. Four different reinforcement learning models are evaluated in the various environments.

    By evaluating the models on a subset of the Solomon benchmark instances, we find that all models but one improve upon a random baseline. The average learner from each of the successful models was slightly worse than the human crafted baseline. However, the best among the generated models was an actor-critic based model which outperformed the best human baseline model.

    Due to the scalar objective function, the results are not directly comparable to the Solomon benchmark results with hierarchal objectives. None the less, the results are encouraging as a proof of principle with results in line with the human crafted baseline. The results indicate two clear paths for further work. First, applying the formulation to more complex environments with more actions and more powerful state spaces. Secondly, investigate models based on stochastic policies and recurrent neural networks to cope with the inherently partially observed environment.

  • Matsson, Fredrik
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Optimization and Systems Theory.
    Sensor fusion for positioning of an autonomous vehicle2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The automotive industry has currently a high focus on automating road vehicles. Positive environmental impact can be achieved if carsharing becomes more common, aiding fewer cars on the roads. When the human factor in driving decreases, positive effects may be seen in traffic safety. But many challanges remain, for example the questions of liability. The vehicles must be able to detect their surroundings and the sensors need redundancy. Sensor fusion techniques increase the reliability of measurement results by combining measurement results from multiple different sensors. This thesis uses inertial sensors to calculate position and heading. An unscented Kalman filter has been designed and implemented on a demonstrator. The demonstrator consists of an r/c car with autonomous functions. It has a forward-facing camera and it can follow road sidelines. The Kalman filter incorporates measurements from two incremental encoders, a gyroscope and a steering angle sensor. The result shows that the combination of sensor measurements provides a better estimation of position and direction of travel.  

  • Verrax, Paul
    KTH, School of Electrical Engineering and Computer Science (EECS), Automatic Control.
    Model Predictive Control Applied to Ground Source Heat Pumps2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Building heating is one of the most important sources of energy consumption. GroundSource Heat Pumps (GSHP) are efficient heating systems, particularly popular in the Nordiccountries. However, the GSHPs available for the consumer market today typically only utilizebasic control schemes that are relatively inflexible. More advanced strategies such as ModelPredictive Control (MPC) appear as a promising approach to improve comfort while reducingconsumption. The present thesis considers a typical user case of a single family house heatedby a ground source heat pump willing to reduce its environmental impact. We design a MPCcontroller to be used on top of the existing heat pump system and with almost no additionalhardware needed. Specific attention is dedicated to the system’s efficiency in order to reflectthe real working performances of a ground source heat pump. The controller is evaluated insimulation on different scenarios using an identified model of a single family house. The resultsshow the MPC strategy becomes most beneficial when including time varying prices or reducedcomfort during certain hours of the day. When both are conjugated the economic savings areup to 8% despite the loss of efficiency of the heat pump. The controller was implemented andtested on a real system with promising results.

  • Schillinger, Philipp
    et al.
    KTH, School of Electrical Engineering (EES), Automatic Control. Bosch Center for Artificial Intelligence.
    Bürger, Mathias
    Bosch Center for Artificial Intelligence.
    Dimarogonas, Dimos V.
    KTH, School of Electrical Engineering and Computer Science (EECS), Automatic Control.
    Auctioning over Probabilistic Options for Temporal Logic-Based Multi-Robot Cooperation under Uncertainty2018Conference paper (Refereed)
    Abstract [en]

    Coordinating a team of robots to fulfill a common task is still a demanding problem. This is even more the case when considering uncertainty in the environment, as well astemporal dependencies within the task specification. A multirobot cooperation from a single goal specification requires mechanisms for decomposing the goal as well as an efficient planning for the team. However, planning action sequences offline is insufficient in real world applications. Rather, due to uncertainties, the robots also need to closely coordinate during execution and adjust their policies when additional observations are made. The framework presented in this paper enables the robot team to cooperatively fulfill tasks given as temporal logic specifications while explicitly considering uncertainty and incorporating observations during execution. We present the effectiveness of our ROS implementation of this approach in a case study scenario.

  • Sandberg, Josefine
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Water Scarcity in Coastal Areas of Sweden: Assessment of water availability and reservoir sensitivity in Vindö, Värmdö municipality, based on climate change scenarios2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A groundwater assessment of north Vindö in Värmdö municipality has been conducted using a spatial analysis tool that is under development. Vindö is a coastal community characterized by surfaced-, or shallowly covered crystalline rock. Water testing in the area implies that over extraction takes place in several locations as 30 % of the private wells in the area show increased concentration of chloride, pointing towards saltwater intrusion. The tool is based on the theoretical background of the GW-Bal program and provides the user with visual maps presenting reservoir water content on a pixel basis. The assessment is made in the lights of projected climate change for Stockholm County, presented by the United Nations International Panel for Climate Change in their 5 th assessment report released in 2013. The results show a large spatial variance in remaining water content over the year. Many areas remain intact even over the summer season when the inhabitants of the community triples, and some areas show severe reservoir water content impact already in the beginning of the season. Further, the results show that the localization of the wells plays has more significance to the reservoir water content than the specific climate scenarios. The study points to the need for the spatial aspect in groundwater assessment, especially in areas where aquifer quality is sensitive to unbalance and the supply heterogeneity is great – such as in coastal areas with reservoirs in crystalline rock.

  • Garis, Sargon
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Sedimentation of stormwater from construction activities2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Water management in infrastructure projects is an important topic since it could affect the surrounding environment in a negative way. In projects with contaminated land, the water could contain everything from metals to polyaromatic hydrocarbons which entails difficulties in managing. The water can be formed partly by rainwater that falls on the construction site or by excavation below the water level. The water pollution is caused by excavation, foundation, grouting, concrete castings and rock blasting. This water is known as stormwater discharges from construction activities.

    The aim of the thesis is to investigate how the selection and application of methods for stormwater management from construction activities can be simplified and optimized in order to suit Swedish conditions. Further the aim is to evaluate how the information available about different techniques relates to how the contractors work in practice under some conditions.

    The thesis consists of three parts. The first part theoretical description of Swedish laws and requirements dealing with stormwater discharge from construction activities, common purification methods that are used and management of stormwater discharge in the state Washington. The second part is a case study with a study visit at the construction site of Marieholmförbindelsen. The third part consists of analytical calculations and comparisons to measured data.

    The results show that regular containers should only be used to sediment sand particles since the surface area is limited which gives a reduced sedimentation time. They also have a limited flow capacity, which must be followed to work properly. The requirement of self-monitoring and maintenance for the contractor should be increased. In other cases, with smaller particles to settle such as silt, regular containers should not be used greater than as a pre-sedimentation step.

    The results also show that for sedimentation of particles smaller than medium silt it is necessary with a residence time of minimum 10 hours. This means that for the soil type fine silt, which has a particle range between 0.0063mm-0.002mm, the residence time can differs between 10-100 hours. For the soil type clay this would mean a residence time of at least 100 hours which equals more than 4 days. By using traditional sedimentation as purification technique one would either need a huge sedimentation area or a very small flow. Either of these solutions is unreasonable due to economic aspects, space limitations and efficiency.

    Based on the results and conclusions, the following recommendations can be proposed:

    •Regular containers demands a high maintenance and self-monitoring, and isn’t recommended to use in greater occurrence than as a pre-sedimentation step for particles smaller than course silt, which has a particle diameter between 0.02-0.063mm.

    •Use a holistic approach by creating clear guidelines for the contractors.

    •Use the hydraulic efficiency, λ, to ensure a proper configuration and a good separation capacity.

  • Dutrieux, Mariane
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Spatio-temporal species distribution modeling: Application to invasive alien species’ monitoring2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The developments of species distribution modeling techniques have brought new opportunities in the field of biological invasion management. In particular, statistical niche modeling for spatio-temporal predictions of species’ distribution is a widely spread tool that has proved its efficiency. The main purpose of this Master thesis is to study applicability of species distribution modeling to invasive alien species, with the aim of supporting efficient decision-making for their prevention. Some research questions are: how useful can species distribution modeling be for invasives’ prevention? Is distribution modeling technically feasible in the case of invasive species? What types of techniques are recommended to model distributions of IAS? What are the limits of such a tool? The methods employed to answer these questions are literature review and expert advice. I found that species distribution models can provide risk maps which are necessary to enable effective invasive alien species’ prevention. However intrinsic characteristics of invasives introduce uncertainties in the predictions made. Consequently several preliminary analyses should be conducted before applying the distribution model. Finally recommendations were made on the most appropriate distribution modeling technique to use depending on the urgency of the situation and the availability of data.

  • Jeppsson, Tobias
    Department of Ecology, The Swedish University of Agricultural Sciences; Centre of Ecological and Evolutionary Synthesis, University of Oslo.
    The many forms of beta diversity: a comment on McGill et al. and some notational suggestions2017In: PeerJ Preprints, E-ISSN 2167-9843, article id 5:e3157v1Article in journal (Other academic)
    Abstract [en]

    Fundamentally, beta diversity is a measure of species turnover across time or space. In practice, it is sometimes unclear exactly what aspect of beta diversity that is implied in studies. For instance, a trend in ’spatial beta diversity’ can be used to refer to both differences in spatial beta diversity between sites, as well as a temporal trend in spatial beta diversity (at the same site). In a recent review, McGill et al. [1] provide a useful and much needed overview of different aspects of biodiversity change, and show areas where we lack knowledge. Even so, McGill et al. ignore some aspects of beta diversity and sometimes pool different types of beta diversity under the same heading. However, their review mainly focused on temporal trends in diversity, while I here want to highlight spatial patterns in temporal β -diversity (species turnover) as an important but somewhat overlooked component of biodiversity change. Furthermore, I propose a slightly modified classification and nomenclature of metrics of biodiversity change, with the aim of complementing their review. The notation used here can hopefully be useful to other authors as well.

  • Ruiz-Alejos, Carlos
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Sustainability Assessment of Scenarios: Beyond GDP growth2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The creation of futures scenarios is a tool to addresschallenges towards sustainability in planning and thebuilt environment. Scenarios in the project BeyondGDP growth explore futures where priority is givento social and environmental aspects and economicgrowth is regarded as uncertain. When futures areused as an input to planning, there has to be anawareness of the possible consequences of those.Sustainability assessment for futures scenarios aimsto give a comprehensive assessment of how differentscenarios can affect relevant aspects.

    This thesis gives an overview of current methods forsustainability assessment of futures scenarios. It alsoproposes improvements to one of them and tests iton the Beyond GDP growth scenarios. SAFS (SustainabilityAssessment Framework for Scenarios) isthe method selected. SAFS considers environmentaland social aspects providing qualitative results anduses consumption perspective and life cycle approach.

    Improvements to SAFS are proposed in two directions.First, the Doughnut developed by Raworth(2012) is integrated in the method. It gives a graphicrepresentation, putting each aspect in context withthe others and facilitate the communication of theassessment results. Second, an alternative approachis suggested to evaluate the consequences of environmentaldeprivation on social conditions. Thisalternative approach can also help communicateuncertainties.

  • Sajadi, Arash
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Strategic Sustainability Studies.
    Nudging - Verktyg för hållbar konsumtion?2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Beteende styr många gånger de val som individer beslutar sig för. Ett visst beteende inom exempelvis val av transport, energi och mat kan många gånger fortgå trots att det är ett beteende som varken är gynnsamt för individen eller för samhället i stort. Nudging som verktyg anses kunna förändra individers beteenden inom områden som hållbar konsumtion så att valen som individer beslutar sig för gynnar de mål som miljöpolitiken bestämt samtidigt som det bevarar individens valfriheten.

    I mars 2017 riktade regeringen ett uppdrag till ansvarig myndighet där termen nudging nämndes vilket har lett till ett ökat intresse för användningen av nudging, speciellt inom hållbar konsumtion.Syftet med denna studie har varit att undersöka vetenskapen bakom nudging-metodiken och dess tillämpning inom hållbar utveckling med fokus på miljösmart hållbar konsumtion. En empirisk studie tillsammans med en teoretisk bakgrund har genomförts för att kunna besvara på forskningsfrågorna:

    1. Hur har förväntningarna kring nudging som metod för beteendeförändring inom hållbar konsumtion infriats?

    2. Vilka begränsningar existerar kring nudging-metodiken?

    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    State of the art of Life Cycle Inventory data for electric vehicle batteries2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • Public defence: 2018-04-13 09:30 M108, Stockholm
    Zangeneh Kamali, Abbas
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges. ELU Konsult AB.
    Dynamic Soil-Structure Interaction Analysis of Railway Bridges: Numerical and Experimental Results2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The work reported in this thesis presents a general overview of the dynamic response of short-span railway bridges considering soil-structure interaction. The study aims to identify the effect of the surrounding and underlying soil on the global stiffness and damping of the structural system. This may lead to better assumptions and more efficient numerical models for design.A simple discrete model for calculating the dynamic characteristics of the fundamental bending mode of single span beam bridges on viscoelastic supports was proposed. This model was used to study the effect of the dynamic stiffness of the foundation on the modal parameters (e.g. natural frequency and damping ratio) of railway beam bridges. It was shown that the variation in the underlying soil profiles leads to a different dynamic response of the system. This effect depends on the ratio between the flexural stiffness of the bridge and the dynamic stiffness of the foundation-soil system but also on the ratio between the resonant frequency of the soil layer and the fundamental frequency of the bridge.

    The effect of the surrounding soil conditions on the vertical dynamic response of portal frame bridges was also investigated both numerically and experimentally. To this end, different numerical models (i.e. full FE models and coupled FE-BE models) have been developed. Controlled vibration tests have been performed on two full-scale portal frame bridges to determine the modal properties of the bridge-soil system and calibrate the numerical models. Both experimental and numerical results identified the substantial contribution of the surrounding soil on the global damping of short-span portal frame bridges. A simplified model for the surrounding soil was also proposed in order to define a less complicated model appropriate for practical design purposes.

  • Borgemo, Joakim
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Learning.
    Roth, Richard
    KTH, School of Industrial Engineering and Management (ITM), Learning.
    Gymnasiefysikens meteorologiinnehåll: En metodkombinationsstudie om hur klimat och väder implementerats i fysikundervisningen2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study examined the implementation and teaching of climate and weather which was added in the year 2011 under Physics 1 in the Swedish upper secondary school. The study performed a mixed-methods approach consisting of teacher interviews supplemented with an interview with an official at the Swedish National Agency for Education and with text analysis of course books. The teacher’s experienced some problems related to what the new subject area would contain. The uncertainty about what the area would contain was also seen in the course books. The interviewees’ opinion that the important issues in the subject area were the greenhouse effect and global warming were shared among the teachers. The greenhouse effect and global warming also had prominent roles in the course books. From the interviews it was found that teachers were positive to include Socio-Scientific Issues (SSI) into their teaching, but when assessing students learning the concepts of physics were emphasized. Cross-disciplinary cooperation was described by the teachers as desirable and often occurring.

  • Public defence: 2018-04-13 10:00 FR4 Oskar Kleins Auditorium, Stockholm
    Lindbo, Sarah
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Protein Technology.
    Generation and engineering of ABD-derived affinity proteins for clinical applications2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Proteins that specifically recognize and bind to other molecules or structures are important tools in industrial and medical applications. Binding proteins engineered from small stable scaffold proteins have been utilized for several purposes due to their favorable biophysical properties, tolerance to mutagenesis, efficient tissue penetration and ease of production. The 46 amino acid long albumin-binding domain (ABD) derived from the bacterial receptor Protein G is a promising scaffold that has been explored in this thesis. The scaffold was subjected to combinatorial protein engineering for generation of ABD-derived binding proteins with novel specificities. Furthermore, the medical potential of engineered ABD- derived affinity proteins (ADAPTs) was evaluated in a series of pre-clinical studies.

    In the first studies, ADAPTs suitability as tracers for radionuclide molecular imaging was evaluated. Factors influencing biodistribution and tumor targeting properties were assessed in mice models bearing HER2 positive xenografts. All tested ADAPT constructs demonstrated high and specific targeting of HER2-expressing tumor cells as well as fast clearance from circulation. The results also showed that the size and character of the N- terminus affected the biodistribution profile of ADAPTs. Moreover, the targeting properties of ADAPTs proved to be highly influenced by the residualizing properties of the attached radionuclide label. Taken together, the results provided the first evidence that tumor imaging can be performed using ADAPTs and the favorable pharmacokinetic profiles in the studied mice models suggest that the scaffold is a promising candidate for clinical applications.

    In the last study, a platform for generation of stable ABD-derived affinity proteins with novel binding specificities was established using a multi-step approach combining directed evolution and rational protein design. A broad combinatorial protein library with 20 randomized positions in ABD was designed and binders against three distinct targets were selected using phage display. Characterization of the selected binders provided information regarding optimal positions to randomize in a final library. In addition, the isolated binders were subjected to mutagenesis in certain surface exposed positions and mutations that provided increased stability were introduced into the original scaffold. Finally, a more focused combinatorial protein library consisting of 11 randomized positions was designed and constructed. The library was validated by selections against the same set of targets as for the first, broad library. The isolation of highly stable affinity ligands confirms that the library can be used for generation of diverse and stable affinity molecules.

  • Wikman, Katarina
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Stockholm Stads Biogaskedja: En energiflödesanalys av biogasproduktion från matavfall2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Stockholm stad har en tydlig formulerad målbild för hur Stockholm skall utvecklas till en hållbar storstad där energianvändning och farliga utsläpp är minimala. Denna målbild framgår i stadens Vision för år 2030, där bland annat ett mål om att staden ska vara fossilbränslefri till år 2050 framgår. Staden har utifrån Vision 2030 satt upp en rad miljömål som bland annat innefattar miljöeffektiva transporter och hållbar energianvändning. Utifrån dessa miljömål har en biogasstrategi utvecklats vars syfte är att bidra till en ökad produktion av biogas i regionen.

    Rapporten kartlägger den rådande biogaskedjan för Stockholm stad, från insamling av matavfall till hantering, biogasutvinning och distribution. De olika delmomenten i biogaskedjan analyseras utifrån energiflödet i den aktuella delprocessen.

    Inom Stockholm stad samlas matavfall in från hushåll och verksamheter. Matavfallet samlas in med biogasdrivna sopbilar som kör matavfallet till SRVs förbehandlingsanläggning i Sofielund. Där förbehandlas matavfallet till en homogeniserad, pumpbar massa som kallas slurry. Slurryn lastas på tankbilar som kör det förbehandlade matavfallet till tillgängliga rötningsanläggningar i regionen.

    Vid rötningsanläggningen placeras slurryn i en rötkammare där biogasutvinningen sker. Uppgradering av rågas sker vanligen i anslutning till rötningsanläggningen. Den vanligaste distributionsformen av fordonsgas är i komprimerad form. Rågasen fylls i stålflaskor och transporteras sedan med lastbil.

    Energiinnehållet i biogasen är direkt kopplad till metanhalten. Metanhalten i den producerade biogasen beror på effektiviteten i rötningsanläggningen samt sammansättningen på slurryn.

    Nettoenergivinsten beräknas till 43 procent av energin som fås vid rötning av 1 ton organiskt hushållsavfall.

    De största energiemissionerna sker på grund av långa transporter mellan förbehandlingsanläggningen och rötningsanläggningen. För en energieffektiv biogasproduktion bör samtliga processteg ske i nära anslutning till varandra så att energianvändning och transporter kan minimeras.

    Energianalysen visar att så som biogaskedjan i Stockholm är konstruerad i dagsläget, är den ej förenlig med stadens miljömål om miljöeffektiva transporter och hållbar energianvändning. 

  • Tapia, Luis Carlos Felix
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Sustainability Assessment of Hydrogen Production Techniques in Brazil through Multi-Criteria Analysis2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Current global demands for energy resources along with continuous global population growth have placed natural environments and societies under great stress to fulfill such a need without disrupting economic and social structures. Policy and decision-making processes hold some of the most important keys to allow safe paths for societies towards energy security and safeguard of the environment. Brazil has played a lead role within renewable energy production and use during the last decades, becoming one of the world’s leading producer of sugarcane based ethanol and adapting policies to support renewable energy generation and use. Although it is true that Brazil has historic experience with managing development of renewables and its further integration into the consumer market, there is still a lot to do to impulse new technologies that could further reduce emissions, increase economic stability and social welfare.

    Throughout this thesis project a sustainability assessment of hydrogen production technologies in Brazil is conducted through Multi-Criteria Analysis. After defining an initial framework for decision-making, options for hydrogen production were reviewed and selected. Options were evaluated and weighted against selected sustainability indicators that fitted the established framework within a weighting matrix. An overall score was obtained after the assessment, which ranked hydrogen production techniques based on renewable energy sources in first place. Final scoring of options was analyzed and concluded that several approaches could be taken in interpreting results and their further integration into policy making. Concluding that selection of the right approach is dependent on the time scale targeted for implementation amongst other multi-disciplinary factors, the use of MCA as an evaluation tool along with overarching sustainability indicators can aid in narrowing uncertainties and providing a clear understanding of the variables surrounding the problem at hand.

  • Mata Yandiola, Cristina
    KTH, School of Industrial Engineering and Management (ITM). Selco Foundation.
    Feasibility Analysis of the use of Hybrid Solar PV-Wind Power Systems for Grid Integrated Minigrids in India2017Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Reliable electricity supply remains a major problem in rural India nowadays. Renewable off-grid solutions have been applied in the last decades to increase power supply reliability but often failed to be feasible due to their high energy costs compared to the national grid. Grid Integrated Mini-grids with Storage (GIMS) can provide reliable power supply at an affordable price by combining mini-grids and national grid facilities. However, research on the techno-economic feasibility of these systems in the country is very limited and unavailable in the public sphere. This research project analysed three different aspects of the GIMS feasibility. First, the feasibility of the use of hybrid wind and solar Photovoltaic (PV) systems in GIMS was analysed by comparing the Levelised Cost of Electricity (LCOE) and Net Present Cost (NPC) of solar PV and hybrid PV/Wind GIMS systems. Second, the potential savings GIMS can offer due to the possibility of selling power to the grid were quantified by comparing the LCOE and NPC of the system with and without grid export. Lastly, the cost of reliability of the power supply was represented by the influence of the allowed percentage of capacity shortage on the total cost of the system. The analysis was carried out by means of the software HOMER and was based on three case studies in India. The results of this analysis showed that the use of hybrid systems could generate savings of up to 17% of the LCOE of the GIMS system in comparison to solar mini-grids. Moreover, power sales to the grid enabled LCOE savings up to 35% with respect to mini-grid without power sell-back possibility. In addition, the LCOE could be reduced in between 28% and 40% in all cases by enabling up to a 5% of capacity shortage in the system.

    et al.
    KTH, School of Industrial Engineering and Management (ITM).
    KTH, School of Industrial Engineering and Management (ITM).
    Liquidity risk in real estate investments from a perspective of institutional investors2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • Huledal, Mattias
    et al.
    KTH, School of Industrial Engineering and Management (ITM).
    Wirström, Li
    KTH, School of Industrial Engineering and Management (ITM).
    Factors Affecting Employees' Participation in Employee Driven Innovation A case study at Viaplay during the innovation initiative called Hack Days2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • Holopainen, Mika
    KTH, School of Industrial Engineering and Management (ITM).
    Business model innovation to manage dominant design A case study at Tele2 and Comviq2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    et al.
    KTH, School of Industrial Engineering and Management (ITM).
    KTH, School of Industrial Engineering and Management (ITM).
    Controlling product complexity over time in a modular product architecture A case study of a home appliance company2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • Yu, Hong
    KTH, School of Information and Communication Technology (ICT).
    Creating Public Trust in Electronic Voting Systems2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There are many positive aspects of electronic voting systems: security, verifiability, convenience, resource conservation, and the like. However, there is still lack of trust for electronic voting systems within the public. One of the reasons could be that the notions involved in electronic voting are challenging to understand for the general public. In this project, we tried to create public trust through an explanation system.

    An explanation system was made to explain how a modern electronic voting system works. User testing was performed after that, to verify whether this explanation system is able to increase people’s trust in electronic voting system. After analysing the data collected through the user testing, we got promising results to believe that this explanation can be used to create public trust in electronic voting systems.

  • Stenbeck, Filip
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Lobell, Oden
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Mechatronics.
    Localization and Mapping for Outdoor Mobile Robots with RTK GPS and Sensor Fusion: An Investigation of Sensor Technologies for the Automower Platform2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The following thesis addresses the problem of localizing an outdoor mobile robot and mapping the environment using the state of the art of consumer grade RTK GPS. The thesis investigates limitations and possibilities for sensor fusion to increase reliability and usability. The main subject of research is a robotic lawn mower from Husqvarna, the Automower 430x, connected to existing hardware on the product with an auxiliary real time kinematic global positioning system, the Emlid Reach. The test conducted showed that the auxiliary RTK GPS module is currently unsatisfactory as sole absolute position sensor for the Automower platform, mainly due to inconsistent performance. This thesis is meant as a preliminary study for future use of GNSS sensors for outdoor mobile robots and as a suggestive study of the current performance of the increasingly popular Emlid Reach GPS module.

    KTH, School of Industrial Engineering and Management (ITM).
    THE IMPENDING EMERGENCE OF (SOCIAL NETWORK) PAYMENTS: A study of the current situation of the mobile payments industry in Sweden and the challenges within the ecosystem.2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    et al.
    KTH, School of Industrial Engineering and Management (ITM).
    KTH, School of Industrial Engineering and Management (ITM).
    An Analysis of the Co-working Space Industry in Stockholm froman Entrepreneurial Perspective2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    KTH, School of Industrial Engineering and Management (ITM).
    The Innovation of Augmented Realityin the Tourism Industry A Case Study of the Tourism Destination Stockholm2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    KTH, School of Industrial Engineering and Management (ITM).
    Opportunities to Digitize Healthcare The case of the infectious disease ward at Danderyds Sjukhus2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • Kamras, Ludwig
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics.
    Matslova, William
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics.
    An approach to a Multi-Category Recommendation System using Machine Learning: With the caveat of having limited knowledge in related areas2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Machine learning is one of many buzz words in todays tech-world. Huge company resources are allocated to the field in order to discover its potential. Everything from cameras to cars tries to use this technology. However, the question is if developers with little experience in the field can use this technology in a useful way? And how would one proceed with that? This thesis tries to answer these questions by having two third year undergraduate students attempt to implement a multi-category movie recommendation system using machine learning. With the important caveat of neither student having any previous knowledge in machine learning, recommendation systems nor the chosen programming language (Python).

    An extensive background study was performed in order to obtain knowledge in the different areas. Recommendation systems often use either collaborative, or content-based filtering, or a hybrid of the two. Machine learning uses different algorithms, a selection of these where studied together with available frameworks.

    In order to implement and design a system, a data-set from MovieLens, containing ratings of movies, and the framework SciKit-learn was used. The implementation tried to use genres in order to give movie recommendations. This was done in two systems, one where every user got a genre-weight and the other system used Nearest Neighbor in order to use the collaborative filtering approach. However, due to the limited time the implementation was not implemented for multiple categories, but the results showed that this should be highly applicable using the proposed design.

    The thesis showed that even two third year undergraduate students with no prior knowledge in the areas could make use of machine learning in an system implementation. The results of the project was presented in two different parts; Firstly, the system implementation result showed that the accuracy metric was not at a satisfactory level. Even though the concept of using genres as a metric for giving recommendations worked, it was seemingly to simple and broad. Secondly, the project result showed that the majority of the time was spent on the preliminary work and the system implementation. Finally the economical cost of the project was presented.

  • Scott, Robert
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics.
    Östberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics.
    A comparative study of open-source IoT middleware platforms.2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This is a comparative study of open-source IoT middleware platforms with the main focus on scalability and reliability. An initial evaluation of available open-source IoT platforms resulted in Kaa and Node-RED being the focus of this thesis. To further analyse the platforms, they were both subjected to testing with three real-world scenarios. The chosen scenarios were a remote-controlled LED, a chat application and a data transmitting sensor. Prototypes were developed for each scenario using a range of programming languages and devices like Raspberry Pi, Android and ESP8266.According to the tests Node-RED has better performance on a single server. It also scales better with the possibility to communicate with external APIs directly unlike Kaa which would require a gateway. Despite these factors, Kaa proved to have better overall scalability and reliability with its built-insecurity and device discovery, it also supports clustering and should prove better in larger environments.

  • Widing, Björn
    et al.
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Mathematical Statistics.
    Jansson, Jimmy
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Mathematical Statistics.
    Valuation Practices of IFRS 172018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This research assesses the IFRS 17 Insurance Contracts standard from a mathematical and actuarial point of view. Specifically, a valuation model that complies with the standard is developed in order to investigate implications of the standard on financial statements of insurance companies. This includes a deep insight into the standard, construction a valuation model of a fictive traditional life insurance product and an investigation of the outcomes of the model.

    The findings show firstly that an investment strategy favorable for valuing insurance contracts according to the standard may conflict with the Asset & Liability Management of the firm. Secondly, that a low risk adjustment increases the contractual service margin (CSM) and hence the possibility of smoothing profits over time. Thirdly, that the policy for releasing the CSM should take both risk-neutral and real assumptions into account. 

  • Hensman, Paulina
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Intra-prediction for Video Coding with Neural Networks2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Intra-prediction is a method for coding standalone frames in video coding. Until now, this has mainly been done using linear formulae. Using an Artificial Neural Network (ANN) may improve the prediction accuracy, leading to improved coding efficiency.

    In this degree project, Fully Connected Networks (FCN) and Convolutional Neural Networks (CNN) were used for intra-prediction. Experiments were done on samples from different image sizes, block sizes, and block contents, and their effect on the results were compared and discussed.

    The results show that ANN methods have the potential to perform better or on par with the video coder High Efficiency Video Coding (HEVC) in the intra-prediction task. The proposed ANN designs perform better on smaller block sizes, but different designs could lead to better performance on larger block sizes. It was found that training one network for each HEVC mode and using the most suitable network to predict each block improved performance of the ANN approach.

    et al.
    KTH, School of Industrial Engineering and Management (ITM).
    KTH, School of Industrial Engineering and Management (ITM).
    Trading with digital ads A possible future scenario2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    et al.
    KTH, School of Industrial Engineering and Management (ITM).
    KTH, School of Industrial Engineering and Management (ITM).
    Exploring the human capital assessment process used by venture capitalists An investigation of Swedish-based VC firms2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    et al.
    KTH, School of Industrial Engineering and Management (ITM).
    KTH, School of Industrial Engineering and Management (ITM).
    A study of sustainability and digital sustainability communication within the steel industry2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    et al.
    KTH, School of Industrial Engineering and Management (ITM).
    KTH, School of Industrial Engineering and Management (ITM).
    An Empirical Analysis Explainingthe Challenges of Using a CONWIP System2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    KTH, School of Industrial Engineering and Management (ITM).
    Patent portfolio analysis as anegotiation tool a case study in the automotive industry2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    et al.
    KTH, School of Industrial Engineering and Management (ITM).
    KTH, School of Industrial Engineering and Management (ITM).
    Strategic Reasons for ModularizationImplications of having a modular product architecture2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    KTH, School of Industrial Engineering and Management (ITM).
    Har geoenergi en chans? Geoenergins relativa fördel i Sveriges kommuner2017Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
  • Kriukelyte, Erika
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies.
    New challenges for transport planning: the institutionalization of mobility as a service in the Stockholm region2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The new trends and challenges are transforming the traditional way of thinking and planning transport systems, with concepts like mobility as a service (MaaS) developing as a result of these transformations. Whilst, the concept of MaaS is still considered new, it is attracting attention from both researchers as well as actors involved within the transport sector. Countries are investigating, testing, and developing the MaaS concept, and Sweden is an active participant in this process with leading pilot projects and other initiatives in metropolitan areas of Stockholm and Gothenburg. However, the definition and ideas about this mobility solution are still not fully defined, and it is not clear how the implementation of the new ideas could and should be institutionalized in the real-life practices. Therefore, this thesis explores and discusses the institutionalisation of MaaS in the public sector in the Stockholm region. The theoretical approach of this thesis is based on institutional theory, which is used to guide the collection of data and analysis of the gathered dataset. The study utilises the method of document analysis and semi-structured interviews to collect information and abductive reasoning for further investigation. The empirical analysis draws attention to three overall aspects of ongoing institutionalization of MaaS: 1) the explanation of the process and drivers of it; 2) the emergence of new challenges; 3) and the impact of the institutionalization of MaaS to the public organizations. The final discussion suggests that in the Stockholm region the institutionalisation of MaaS is still nominal and uncertain when considered in general transport planning between the public organisations. However, the actors discussed are in the process of identifying the core challenges and are working to address them. These actions and changes manifest in the transforming roles and positions with the actors' network; in the development of new collaborations; and in the altering of future ambitions in the transport planning and the linkages to the long-term spatial infrastructural planning, which still lacks attention. The study outlines key areas of future research, including issues with the evolving requirements MaaS can bring to the transport infrastructure and the need for short- and long-term analysis of the MaaS impact to the sustainable transport system.