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  • Presentation: 2017-05-30 13:00 M108, Stockholm
    Neves, Cláudia
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Structural Health Monitoring of Bridges: Model-free damage detection method using Machine Learning2017Licentiate thesis, monograph (Other academic)
    Abstract [en]

    This is probably the most appropriate time for the development of robust and reliable structural damage detection systems as aging civil engineering structures, such as bridges, are being used past their life expectancy and beyond their original design loads. Often, when a significant damage to the structure is discovered, the deterioration has already progressed far and required repair is substantial. This is both expensive and has negative impact on the environment and traffic during replacement. For the exposed reasons the demand for efficient Structural Health Monitoring techniques is currently extremely high. This licentiate thesis presents a two-stage model-free damage detection approach based on Machine Learning. The method is applied to data gathered in a numerical experiment using a three-dimensional finite element model of a railway bridge. The initial step in this study consists in collecting the structural dynamic response that is simulated during the passage of a train, considering the bridge in both healthy and damaged conditions. The first stage of the proposed algorithm consists in the design and unsupervised training of Artificial Neural Networks that, provided with input composed of measured accelerations in previous instants, are capable of predicting future output acceleration. In the second stage the prediction errors are used to fit a Gaussian Process that enables to perform a statistical analysis of the distribution of errors. Subsequently, the concept of Damage Index is introduced and the probabilities associated with false diagnosis are studied. Following the former steps Receiver Operating Characteristic curves are generated and the threshold of the detection system can be adjusted according to the trade-off between errors. Lastly, using the Bayes’ Theorem, a simplified method for the calculation of the expected cost of the strategy is proposed and exemplified.

  • Presentation: 2017-05-31 10:00 4523, Stockholm
    Rodríguez-Cano, Guillermo
    KTH, School of Computer Science and Communication (CSC), Theoretical Computer Science, TCS.
    Toward Privacy-Preserving Decentralised Systems2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Privacy enhancing technologies have proven to be a beneficial area of research lessening the threats users' privacy in centralised systems such as online social networks. Decentralised solutions have been proposed to extend the control that users have over their data as opposed to the centralised massive collection of personal and sensitive data.

    The power that the service provider has in centralised systems has been shown to diminish the user’s privacy. Moreover, the disclosures in 2013 of a global surveillance program in collaboration with some of the service providers of such centralised systems have accelerated the debate on how to take action to counteract the threats to privacy.

    Privacy-preserving decentralised systems are plausible solutions to such threats. However, the removal of the central authority comes with two main trade-offs, mimicking the features and taking over the supervision of the security and privacy threats that were a responsibility of the central authority.

    In our thesis, we propose the use of privacy-preserving decentralised systems and develop three solutions in terms of decentralisation, functionality, and achievable security and privacy. For decentralised systems we show a mechanism for user authentication via standard credentials. Within the realm of decentralised online social networks we implement a coordination and cooperation mechanism to organise events without the need of a trusted third party. Finally, we improve one of the aspects of the user’s privacy: anonymity, by showing an implementation of a privacy-preserving system to submit and grade documents anonymously in systems where the central authority is still required.

    Our solutions are some concrete examples of how privacy as data control can be achieved to varying degrees. Nonetheless, we hope that the protocols we propose and the evaluation of the security and privacy properties can be useful in other scenarios to mitigate the diverse dangers to personal privacy.

    The full text will be freely available from 2017-05-31 10:00
  • Presentation: 2017-06-02 10:00
    Nikou, Alexandros
    KTH, School of Electrical Engineering (EES), Automatic Control.
    Cooperative Planning Control and Formation Control of Multi-Agent Systems2017Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Cooperative planning control is an active topic of research, with many practical applications including multi-robot systems, transportation, multi-point surveillance and biological systems. The contributions of this thesis lie in the scope of three topics: formation control, time-constrained cooperative planning control and probabilistic control synthesis, all of the them in the framework of multi-agent systems.

    In the first part of the thesis, given a team of rigid-bodies, we propose decentral-ized control protocols such that desired position and orientation-based formationbetween neighboring agents is achieved. Inter-agent collisions and collisions betweenagents and static obstacles of the workspace are guaranteed to be avoided by theproposed control scheme. Furthermore, the connectivity between the agents thatare initially connected is preserved. In the second part of the thesis, we considera team of agents, modeled by coupled single-integrator dynamics. Each agent isassigned with individual high-level tasks, given in Metric Interval Temporal Logic(MITL). By abstracting the motion of each agent into Transition Systems (TS), wepropose decentralized control methodologies that guarantee the satisfaction of thedesired tasks of each agent. In the final part, a coupled multi-agent system underthe presence of uncertainties and model errors is considered. Each agent is modeledby a Markov Decision Process (MDP) and is assigned with a high-level task givenin Probabilistic Computational Tree Logic (PCTL). The goal is to design controlpolicies such that each agent is performing a desired task. By clustering the agentsinto dependency clusters, we propose control algorithms that guarantee that thedesired specifications are fulfilled. Numerical simulations conducted in MATLABverify the claimed results.

  • Presentation: 2017-06-05 13:00 304, Stockholm
    Hyttinen, Emil
    KTH, School of Computer Science and Communication (CSC), Robotics, perception and learning, RPL. KTH, School of Computer Science and Communication (CSC), Centres, Centre for Autonomous Systems, CAS.
    Adaptive Grasping Using Tactile Sensing2017Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Grasping novel objects is challenging because of incomplete object data and because of uncertainties inherent in real world applications. To robustly perform grasps on previously unseen objects, feedback from touch is essential. In our research, we study how information from touch sensors can be used to improve grasping novel objects. Since it is not trivial to extract relevant object properties and deduce appropriate actions from touch sensing, we employ machine learning techniques to learn suitable behaviors. We have shown that grasp stability estimation based on touch can be improved by including an approximate notion of object shape. Further we have devised a method to guide local grasp adaptations based on our stability estimation method. Grasp corrections are found by simulating tactile data for grasps in the vicinity of the current grasp. We present several experiments to demonstrate the applicability of our methods. The thesis is concluded by discussing our results and suggesting potential topics for further research.

  • Presentation: 2017-06-07 10:15 E2, Stockholm
    Kleusberg, Elektra
    KTH, School of Engineering Sciences (SCI), Mechanics, Stability, Transition and Control.
    Wind turbine simulations using spectral elements2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Understanding the flow around wind turbines is a highly relevant research question due to the increased interest in harvesting energy from renewable sources. This thesis approaches the topic by means of numerical simulations using the actuator line method and the incompressible Navier–Stokes equations in the spectral element code Nek5000. The aim is to gain enhanced understanding of the wind turbine wake structure and wind turbine wake interaction. A verification study of the method and implementation is performed against the finite volume solver EllipSys3D using two types of turbines, an idealized constant circulation turbine and the Tjæreborg turbine. It is shown that Nek5000 requires significantly lower resolution to accurately compute the wake development, however, at the cost of a smaller time step.The constant circulation turbine is investigated further with the goal of establishing guidelines for the use of the actuator line method in spectral element codes, where the mesh is inherently non-equidistant and currently used guidelines of force distribution based on Gaussian kernels are difficult to apply. It is shown that Nek5000 requires a larger kernel width in the fixed frame of reference to remove numerical instabilities. Further, the impact of different Gaussian widths on the wake development is investigated in the rotating frame of reference, showing that the convection velocity and the breakdown of the spiral tip and root vortices are dependent on the Gaussian width. In the second part, the flow around single and multiple wind-turbine setups at different operating conditions is investigated and compared with experimental results. The focus is placed on comparing the power and thrust coefficients and the wake development based on the time-averaged streamwise velocity and turbulent stresses. Further the influence of the tower model is investigated both upstream and downstream of the turbine. The results show that the wake is captured accurately in most cases. The loading exhibits a significant dependence on the Reynolds number at which the airfoil data is extracted. When the helical tip vortices are stable the turbulent stresses at the tip vortices are underestimated in the numerical simulations. This is due to the finite resolution and the projection of the actuator line forces in the numerical domain using a prescribed Gaussian width, which leads to lower induced velocities in the helical vortices.

  • Presentation: 2017-06-07 13:00 Sal C, Stockholm
    Ahmed, Ashraf Awadelkarim Widaa
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Towards Affordable Provisioning Strategies for Local Mobile Services in Dense Urban Areas: A Techno-economic Study2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The future mobile communication networks are expected to cope with growing local usage patterns especially in dense urban areas at more affordable deployment and operation expenses. Beyond leveraging small cell architectures and advanced radio access technologies; more radio spectrum are expected to be required to achieve the desired techno-economic targets. Therefore, the research activity has been directed towards discussing the benefits and needs for more flexible and local spectrum authorization schemes. This thesis work is meant to be a contribution to this ongoing discussion from a techno-economic perspective.

     

    In chapter three, the engineering value of the different flexible authorization options are evaluated from the perspective of established mobile network operators using the opportunity cost approach. The main results in chapter three indicate the economic incentives to deploy more small cells based on flexible spectrum authorization options are subject to the potential saving in the deployment and operation costs. Nonetheless; high engineering value can be anticipated when the density of small cells is equal or larger than the active mobile subscribers’ density.

     

    While in chapter four, the possible local business models around different flexible authorization options are investigated from the perspective of emerging actors with limited or ’no’ licensed spectrum resources. In this context, dependent or independent local business can be identified according to surrounding spectrum regulations. On possible independent local business models for those emerging actors is to exploit the different flexible spectrum authorization options to provision tailored local mobile services. Other viable dependent local business models rest with the possibility to enter into different cooperation agreements to deploy and operate dedicated local mobile infrastructure on behalf established mobile network operators.

  • Presentation: 2017-06-09 10:15 Munin, Stockholm
    Blanco, Blas
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Railway track dynamic modelling2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The railway vehicles are an increasing mean of transportation due to, its reduced impact on environment and high level of comfort provided. These reasons have contributed to settle a positive perception of railway traffic into the European society. In this upward context, the railway industrial sector tackles some important challenges; maintaining low operational costs and controlling the nuisance by-products of trains operation, the most important being railway noise. Track dynamic plays a main role for both issues, since a significant part of the operational costs are associated with the track maintenance tasks and, the noise generated by the track can be dominant in many operational situations. This explains why prediction tools are highly valued by railway companies. The work presented in this licentiate thesis proposes methodologies for accurate and efficient modelling of railway track dynamics. Two core axes have led the development of this task, on one hand, the rail modelling and, on the other hand, the characterisation of the finite length nature of track supports. Firstly, concerning the rail modelling technique, it has evolved under two major premises. On one hand, regarding the frequency domain, it should describe high frequency behaviour of the rail. In order to accomplish with this first premise, a model based on Timoshenko beam theory is used, which can accurately account for the vertical rail behaviour up to 2500 Hz. On the other hand, with respect to the time domain, the response should be smooth and free of discontinuities. This last condition is fulfilled by implementation of the Timoshenko local deformation. Secondly, a model of support that considers its finite length nature is sought. For this purpose, a Timoshenko element over elastic foundation is formulated. Thus, the common model of support, which is based on a concentrated connection, is substituted by a distributed model of support. In this way, several enhancements are achieved; the temporal contact force response is smoothed and a more realistic shape is obtained, the amplitude of the displacement due to the parametric excitation is reduced and the magnitude associated to the ‘pin-pin’ frequency is not overestimated.

  • Presentation: 2017-06-09 13:00 V1, Stockholm
    Freitas, Flavio L. M.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Brazilian land use policies and the development of ecosystem services2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Concerns related to global environmental changes due to land use changes have been driving international communities towards more sustainable land use systems. Brazil is a country of global strategic importance in this matter considering that it is the nation with the largest extension of preserved tropical native vegetation, recognised for its ecosystem services and high and unique biodiversity. Expansion of forestry and agriculture is taking place rapidly in Brazil, partly over degraded pastureland, but also over native vegetation. Regulating policies to govern and limit this expansion is crucial to ensure the preservation of the ecosystems services provided by native vegetation.  This thesis aims at improving the understanding of the potential impacts of prevailing public and private policies in the conservation of nature in Brazil. For this end, the Land Use Policy Assessment (LUPA) model was employed to evaluate potential pathways of implementation of the land use policies. Paper 1 evaluated the effects of current private and public command and control regulations in the protection of above-ground carbon stocks, identifying the most relevant stakeholders holding carbon stocks. The findings suggest that about 10% of carbon stocks are unprotected, where other policy instruments based on the market will be mostly required. Paper 2 performed an assessment of the mechanism for offsetting the legal deficit of native vegetation among landholders, evaluating the different offsetting implementation practices and their impacts on nature protection and socio-economic development. The results indicate that the offsetting mechanism may have little or no additional effects on protection of native vegetation and its ecosystem services because most of the offsetting is likely to take place where native vegetation is already protected by current legislations. However, it is viable to maximise environmental and socio-economic returns from the offsetting mechanism.

  • Presentation: 2017-06-12 10:00 Ka-Sal C (Sal Sven-Olof Öhrvik), Electrum, Stockholm
    Cheng, Yuxin
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Passive Optical Top-of-Rack Interconnect for Data Center Networks2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Optical networks offering ultra-high capacity and low energy consumption per bit are considered as a good option to handle the rapidly growing traffic volume inside data center (DCs). However, most of the optical interconnect architectures proposed for DCs so far are mainly focused on the aggregation/core tiers of the data center networks (DCNs), while relying on the conventional top-of-rack (ToR) electronic packet switches (EPS) in the access tier. A large number of ToR switches in the current DCNs brings serious scalability limitations due to high cost and power consumption. Thus, it is important to investigate and evaluate new optical interconnects tailored for the access tier of the DCNs.

    We propose and evaluate a passive optical ToR interconnect (POTORI) architecture for the access tier. The data plane of the POTORI consists mainly of passive components to interconnect the servers within the rack as well as the interfaces toward the aggregation/core tiers. Using the passive components makes it possible to significantly reduce power consumption while achieving high reliability in a cost-efficient way.

    Meanwhile, our proposed POTORI’s control plane is based on a centralized rack controller, which is responsible for coordinating the communications among the servers in the rack. It can be reconfigured by software-defined networking (SDN) operation. A cycle-based medium access control (MAC) protocol and a dynamic bandwidth allocation (DBA) algorithm are designed for the POTORI to efficiently manage the exchange of control messages and the data transmission inside the rack.

    Simulation results show that under realistic DC traffic scenarios, the POTORI with the proposed DBA algorithm is able to achieve an average packet delay below 10 μs with the use of fast tunable optical transceivers. Moreover, we further quantify the impact of different network configuration parameters on the average packet delay. 

  • Presentation: 2017-06-12 10:00 Q2, Stockholm
    Eriksson, Emil
    KTH, School of Electrical Engineering (EES), Network and Systems engineering.
    Distributed Processing of Visual Features in Wireless Sensor Networks2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    As digital cameras are becoming both cheaper and more advanced, they are also becoming more common both as part of hand-held and consumer devices, and as dedicated surveillance devices. The still images and videos collected by these cameras can be used as input to computer vision algorithms for performing tracking, scene understanding, navigation, etc. The performance of such computer vision tasks can be improved by having multiple cameras observing the same events. However, large scale deployment of camera networks is difficult in areas without access to infrastructure for providing power and network connectivity. In this thesis we consider the use of a network of camera equipped sensor nodes as a cost efficient alternative to conventional camera networks. To overcome the computational limitations of the sensor nodes, we enhance the sensor network with dedicated processing nodes, and process images in parallel using multiple processing nodes.

    In the first part of the thesis, we formulate the minimization problem of the time required from image capture until the visual features are extracted from the image. The solution to the minimization problem is an allocation of sub-areas of a captured image to a subset of the processing nodes, which perform the feature extraction. We use the temporal correlation of the image contents to predict an approximation of the distribution of visual features in a captured image. Based on the approximate distribution, we compute an approximate solution to the minimization problem using linear programming. We show that the last value predictor gives a good trade-off between performance and computational complexity.

    In the second part of the thesis, we propose fully distributed algorithms for allocation of image sub-areas to the processing nodes in a multi-camera Visual Sensor Network. The algorithms differ in the amount of information available and in how allocation updates are applied. We provide analytical results on the existence of equilibrium allocations, and show that an equilibrium allocation may not be optimal. We show that fully distributed algorithms are most efficient when sensors make asynchronous changes to their allocations, and in topologies with less symmetry. However, with the addition of sparse coordination, both average and worst-case performance can be improved significantly.

  • Presentation: 2017-06-12 13:00 V1, STOCKHOLM
    Hamisi, Rajabu
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Modelling phosphorus dynamics in constructed wetlands upgraded with reactive filter media2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Phosphorus mobility and sorption mechanisms underlying the removal efficiency of different adsorbent media were evaluated using the SWAT model and 3Dreactive transport model. The aims of the thesis were to: i) improve understanding of phosphorus mobility in the Oxundaån catchment; ii) identify suitable sites for constructing wetlands; iii) develop the numerical reactive transport model in order to identify key parameters which affects sorption efficiencies of the reactive adsorbent media; iv) predict the media's sorption efficiencies; and v) evaluate the viable reactive adsorbent media for mitigating eutrophication in the Baltic Sea. To predict phosphorus removal efficiencies of the adsorbent media and visualize the sorption process within the constructed wetlands, a three-dimensional model was developed within the COMSOL Multiphysics®. The reactive transport model was developed by coupling four physics interfaces to simulate the processes of water flow dynamics, transport of diluted phosphorus species, reaction kinetics and heat transfer in the porous media. The SWAT modelling results showed that arable land with the less background phosphorus retention, lower soil permeability and lower land slope could provide suitable sites for constructing wetlands. The simulated phosphorus sorption efficiency of the reactive filter media was ranked: 88 % (113 g P kg-1) for Polonite®, 85 % (81gP kg-1) for Filtralite P®, 62 % (61 gPkg-1) for Blast furnace slag, 57 % (44gP kg-1) for Wollastonite. In comparison to other media, Polonite® was observed to be a suitable reactive adsorbent media for wetland applications under different hydraulic loading rates and pH change, whose P-removal efficiency last for six years. Moreover, the modelling results showed less significant effects of particle size on the phosphorus removal efficiency as compared to solution pH and Ca mineral content. Precipitation was identified to be the dominant mechanisms for phosphorus removal in these media with the positive correlation to pH increase (R2 = 0.94, p-value = 0.002) and Calcium content (R2 = 0.73, p-value = 0.004). The good agreements between the simulated outputs and experimental data accurately captured the processes of phosphorus mobility and removal. The results suggest that the reactive transport models are valuable tools for providing insight into sorption processes in subsurface systems and improving design criteria for constructed wetlands. More experimental data are needed to calibrate the sensitivity of local parameters in order to better assess the performance of subsurface flow constructed wetlands.

  • Presentation: 2017-06-12 13:15 Q26, Stockholm
    von Oelreich, Jacob
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Shorelines of adaptation and fields of innovation: Emerging sustainability transformations in sea-level rise planning and the food system2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This licentiate thesis builds on the understanding that there is an urgent need for radical and systemic transformations towards sustainability in all parts of society, since current socio-ecological relations are highly unsustainable. The aim of the thesis is to explore emerging societal transformations towards strengthened sustainability through case studies within planning for sea-level rise and the food system, respectively.

    A warmer climate leads to rising sea levels. Although it is uncertain how fast sea levels will rise, and by how much, preparing and adapting to sea-level rise is crucial for society. The global food system is profoundly unsustainable and in need of transformations to sustainability. This thesis links two separate studies, one examining the state of planning for future sea-level rise in Swedish municipalities, the other exploring to what extent organic food initiatives can push the dominant food system in the direction of sustainability transformations. In both studies, the main methods used are qualitative interviews and document surveys.

    The results show that transformational change towards sustainability builds on different strategies in different fields. Whereas in planning for sea-level rise the emphasis lies on handling and adapting to one of the main impacts of climate change, rising sea levels, under conditions of uncertainty, the focus within food systems change directed at sustainability lies on creating sustainable alternatives that can challenge the dominant food regime. However, in both fields there is a need for moving from a currently dominant regime or paradigm to one characterized by sustainability and dynamic robustness, respectively. This requires a shift in understanding of socio-ecological relations, in turn connected to values and politics.

    Key recommendations from this thesis include that planning for sea-level rise should be guided by dynamically robust planning approaches, worst-case scenarios for future sea-level rise should be taken into account, a long-term perspective should be considered, and a national strategy for sea-level rise planning in Sweden should be developed. To strengthen the sustainability of the food system, a variety of organic food initiatives, methods and models should be encouraged, organic food initiatives should persistently strive to build niches and alliances departing from Organic 3.0 values, and as sustainability transformations require radical and systemic changes in values, governance, social practices, policies and economic structures, food systems change should be aimed accordingly.

  • Presentation: 2017-06-12 14:30 Hörsalen byggnad 260, Södertälje
    Olofsson, Anders
    KTH, School of Industrial Engineering and Management (ITM).
    Hardening Distortions of Serial Produced Gears2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Hardening distortions are unwanted changes in shape and dimension that arise during hardening of steel components. Uncontrolled distortions induce random errors to the manufacturing process, and have a strong negative impact on manufacturing costs. The distortions are not only caused by the hardening process, several factors from previous manufacturing steps including the component geometry itself contribute to varying extent. The aim of the current work is to investigate the main influencing factors on hardening distortions for serial produced gears.

    The investigations were done on two different types of gears for heavy-duty transmissions, crown wheels for the rear axle central gear and main shaft gears for the gearbox. The steel was produced using either continuous casting or ingot casting. For rectangular continuously cast steel, the effect of disabling magnetic stirring of the steel melt during casting was investigated, finding a strong reduction of gear runout for crown wheels. Segregations in crown wheels produced from the top and bottom of ingots were shown to go in opposite directions, producing opposite back-face tilts.

    For crown wheels quenched one at a time, influences of stacking level on the hardening tray were found, indicating an impact from small variations in the carburizing process, despite identical quenching conditions. For main shaft gears, horizontal loading gave considerably less roundness and runout errors but increased flatness errors compared to vertical loading.

    This thesis shows the complexity of the distortion phenomenon and how several factors interact and contribute to the final result. It is shown that factors with significant impact on hardening distortions for one component may be less important for another component. With this in mind, each type of component to be hardened should be produced by a manufacturing chain where each process step is carefully chosen with respect to minimizing distortions.

  • Presentation: 2017-06-14 13:00 L52, Stockholm
    Albrecht, Martin
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Enabling socio-technical transitions – electric vehicles and high voltage electricity grids as focal points of low emission futures2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

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

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

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

  • Presentation: 2017-06-15 09:30 Air-Fire, Science for Life Laboratories, Solna
    Unnersjö-Jess, David
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cellular Biophysics.
    High-resolution imaging of kidney tissue samples2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The kidney is one of the most important and complex organs in the human body, filtering hundreds of litres of blood daily. Kidney disease is one of the fastest growing causes of death in the modern world, and this motivates extensive research for better understanding the function of the kidney in health and disease. Some of the most important cellular structures for blood filtration in the kidney are of very small dimensions (on the sub-200 nm scale), and thus electron microscopy has been the only method of choice to visualize these minute structures. In one study, we show for the first time that by combining optical clearing with STED microscopy, protein localizations in the slit diaphragm of the kidney, a structure around 75 nanometers in width, can now be resolved using light microscopy. In a second study, a novel sample preparation method, expansion microscopy, is utilized to physically expand kidney tissue samples. Expansion improves the effective resolution by a factor of 5, making it possible to resolve podocyte foot processes and the slit diaphragm using confocal microscopy. We also show that by combining expansion microscopy and STED microscopy, the effective resolution can be improved further. In a third study, influences on the development of the kidney were studied. There is substantial knowledge regarding what genes (growth factors, receptors etc.) are important for the normal morphogenesis of the kidney. Less is known regarding the physiology behind how paracrine factors are secreted and delivered in the developing kidney. By depleting calcium transients in explanted rat kidneys, we show that calcium is important for the branching morphogenesis of the ureteric tree. Further, the study shows that the calcium-dependent initiator of exocytosis, synaptotagmin, is expressed in the metanephric mesenchyme of the developing kidney, indicating that it could have a role in the secretion of paracrine growth factors, such as GDNF, to drive the branching.

  • Presentation: 2017-06-16 10:00 Gamma 2, Solna
    Wiking, Mikaela
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Spatial proteome profiling of the compartments of the human cell using an antibody-based approach2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The human cell is complex, with countless processes ongoing in parallel in specialized compartments, the organelles. Cells can be studied in vitro by using immortalized cell lines that represent cells in vivo to a varying degree. Gene expression varies between cell types and an average cell line expresses around 10,000-12,000 genes, as measured with RNA sequencing. These genes encode the cell’s proteome; the full set of proteins that perform functions in the cell. In paper I we show that RNA sequencing is a necessary tool for studying the proteome of the human cell.

    By studying the proteome, and proteins’ localization in the cell, information can be assembled on how the cell functions. Image-based methods allow for detailed spatial resolution of protein localization as well as enable the study of temporal events. Visualization of a protein can be accomplished by using either a cell line that is transfected to express the protein with a fluorescent tag, or by targeting the protein with an affinity reagent such as an antibody. In paper II we present subcellular data for a majority of the human proteins, showing that there is a high degree of complexity in regard to where proteins localize in the cell.

    Cellular energy is generated in the mitochondria, an important organelle that is also active in many other different functions. Today approximately only a third of the estimated mitochondrial proteome has been validated experimentally, indicating that there is much more to understand with regard to the functions of the mitochondria. In paper III we explore the mitochondrial proteome, based on the results of paper II. We also present a method for sublocalizing proteins to subcompartments that can be performed in a high-throughput manner.

    To conclude, this thesis shows that transcriptomics is a useful tool for proteome-wide subcellular localization, and presents high-resolution spatial distribution data for the human cell with a deeper analysis of the mitochondrial proteome.

    The full text will be freely available from 2017-06-16 10:00