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  • Presentation: 2017-10-19 10:00 Wretlindsalen, Solna
    Lama, Lara
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Novel methods for improving rapid paper-based protein assays with gold nanoparticle detection2017Licentiate thesis, monograph (Other academic)
    Abstract [en]

    This thesis describes methods for improving sensitivity in rapid singleplex and multiplex microarray assays. The assays utilize the optical characteristics of colloidal gold nanoparticles for the colorimetric detection of proteins.

    Multiplexed detection in sandwich immunoassays is limited by cross-reactivity between different detection antibodies. The cross-reactivity between antibodies can contribute to increased background noise - decreasing the Limit-of-Detection of the assay - or generate false positive signals. Paper I shows improved assay sensitivity in a multiplexed vertical flow assay by the application of ultrasonic energy to the gold nanoparticles functionalized with detection antibodies. The ultrasonication of the antibody conjugated gold nanoparticles resulted in a 10 000 fold increase in sensitivity in a 3-plex assay. COMSOL Multiphysics was used to simulate the acoustical energy of the probe used in Paper I for obtaining an indication of the size and direction of the forces acting upon the functionalized gold nanoparticles.

    In Paper II, it was studied if different gold nanoparticle conjugation methods and colorimetric signal enhancement of the gold nanoparticle conjugates could influence the sensitivity of a paper-based lateral flow microarray assay, targeting cardiac troponin T for the rapid diagnostics of acute myocardial infarction.

    Ultrasonication and signal enhancement of the detection gold nanoparticles has the potential of improving the sensitivity of paper based assays and expanding their potential future applications.

  • Presentation: 2017-10-20 16:04
    Ahlin, Jesper
    Philosophy and History, KTH, School of Architecture and the Built Environment (ABE), Philosophy and History of Technology, Philosophy.
    Personal Autonomy and Informed Consent: Conceptual and Normative Analyses2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This licentiate thesis is comprised of a “kappa” and two articles. The kappa includes an account of personal autonomy and informed consent, an explanation of how the concepts and articles relate to each other, and a summary in Swedish.

    Article 1 treats one problem with the argument that a patient’s consent to treatment is valid only if it is authentic, i.e., if it is “genuine,” “truly her own,” “not out of character,” or similar. As interventions with a patient’s life and liberties must be justified, the argument presupposes that the authenticity of desires can be reliably determined. If the status of a desire in terms of authenticity cannot be reliably determined, discarding the desire-holder’s treatment decision on the basis that it is inauthentic is morally unjustified. In the article, I argue that no theory of authenticity that is present in the relevant literature can render reliably observable consequences. Therefore, the concept of authenticity, as it is understood in those theories, should not be part of informed consent practices.

    Article 2 discusses the problem of what it is to consent or refuse voluntarily. In it, I argue that voluntariness should be more narrowly understood than what is common. My main point is that a conceptualization of voluntariness should be agent-centered, i.e., take into account the agent’s view of her actions. Among other things, I argue that an action is non-voluntary only if the agent thinks of it as such when being coerced. This notion, which at first look may seem uncontroversial, entails the counterintuitive conclusion that an action can be voluntary although the agent has been manipulated or coerced into doing it. In defense of the notion, I argue that if the agent’s point of view is not considered accordingly, describing her actions as non-voluntary can be alien to how she leads her life. There are other moral concepts available to describe what is wrong with manipulation and coercion, i.e., to make sense of the counterintuitive conclusion. Voluntariness should be reserved to fewer cases than what is commonly assumed.

  • Presentation: 2017-10-24 13:00 Stora konferensrummet, Stockholm
    Al-Ayish, Nadia
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology.
    Environmental Impact of Concrete Structures - with Focus on Durability and Resource Efficiency2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Concrete is essential for the construction industry with characteristic properties that make it irreplaceable in some aspects. However, due to the large volumes consumed and the energy intense cement clinker production it also has a notable climate impact. In order to reach the international and national sustainability goals it is therefore important to reduce the climate impact of concrete structures.

    There are many ways to influence the environmental impact of concrete and a detailed analysis is one of the actions that could push the industry and the society towards a sustainable development. The purpose of this research is to evaluate the environmental impact of concrete structures and the built environment and to highlight the possibilities to reduce that impact with choice of concrete mix and innovative design solutions.

    A life cycle assessment (LCA) was carried out to analyze the environmental impact of two thin façade solutions with innovative materials and to evaluate influences of different greenhouse gas reducing measures on concrete bridges. The influence of supplementary cementitious materials (SCM) in terms of climate impact and durability was also analyzed.

    The results indicate that SCMs have a twofold effect on the climate impact of reinforced concrete structures. Not only do they reduce the greenhouse gases through cement clinker replacement but also by an improvement of durability regarding chloride ingress. Currently, this is not considered in the regulations, which makes it difficult to foresee in LCA at early design stages. The results also show great possibilities to reduce the climate impact through different measures and design alternatives and the need for further development of products and solutions.

  • Presentation: 2017-10-26 09:45 Q2, Stockholm
    Malmström, Johan
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Efficient Methods to Calculate Mutual Coupling between Generic Antennas on Large Platforms2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis presents research on methods for calculating the mutual coupling between antennas. The mutual coupling between antennas is a measure of the amount of energy transmitted from one antenna that is received by another, and is a key parameter when installing antennas on platforms, such as aircraft. To avoid interference between systems connected to the antennas, the mutual coupling should be as low as possible. The risk for interference can be minimized in several ways; by designing the systems to be resistant to interference or to install the antennas in a way that makes the coupling between antennas low. This thesis focuses on the latter.

    Electromagnetic problems, such as finding the mutual coupling between antennas, can be calculated in simulations using commercial software. On large platforms, simulations become very computationally intensive. This thesis examines ways to efficiently calculate the mutual coupling between antennas on large platforms. The intention has been to develop methods that can be used in practical situations.

    One possible way to increase efficiency is to use appropriate approximations that simplify calculations. Two approximations have been evaluated; approximate wave propagation model and equivalent representations of antennas. Both of these approximations have the potential to reduced computation times, but suffer from the fact that the size of the errors introduced is not predictable. This contributes to an uncertainty in estimating the coupling between antennas that make them less interesting to use in applications. The reaction theorem, that describes the coupling as an interaction of electromagnetic fields, has been very useful in this work. Two novel formulations of the theorem have been derived that decompose fields into scattered components. It is shown that some of the components do not affect the reaction. The reaction theorem and the derived formulations have been used in two applications. The first application shows practical possibilities to calculate mutual impedance between two antennas installed on a common platform. It is also shown how the reaction theorem can be used to visualize coupling paths, which show how the coupling between the antennas is spatially distributed.

    The second application of the reaction theorem suggests an effective method for antenna placement on platforms that minimize the mutual impedance between antennas. The method enables field data to be reused, which significantly reduces the calculation time. Both suggested applications post-process electromagnetic field data. The field data can be determined with commercial software.

    The main results in this thesis are described in five articles and conference contributions that are or will be published in international scientific journals or at international conferences.

  • Presentation: 2017-10-26 13:00 Ka-Sal C, Electrum, KTH Royal Institute of Technology, Kista
    Celik, Haris
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    On the Performance of Dynamic TDD in Ultra-Dense Wireless Access Networks2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The appetite for wireless high-data rate services is expected to continue for many years to come and drive the need for more capacity. Ultra-dense networks (UDNs) represent a paradigm shift where each base station (BS) serves only a few user equipments (UEs). By most accounts, most of the traffic will be generated indoor and operate in time-division duplex (TDD). This thesis considers dynamic TDD which has shown to perform well indoor for fluctuating traffic where the shorter communication range enables similar transmit powers to be used in uplink and downlink, but also generates potentially more harmful same-entity interference. Because of the sheer number of cells in UDN, the interference management needs to be both effective and scalable.

     

    In the first part of the thesis, we compare static TDD with non-cooperative dynamic TDD and show that flexible time resource allocation is preferred for indoor UDNs. However, since it only provides a lower bound on performance, additional interference coordination is required. Unfortunately, existing schemes often consider either too few, too many, or simply the wrong interferers. We introduce a scheduling model that relates BS-to-BS interferences measured offline to individual BS activation probability taking into account traffic and propagation environment. Results show that the proposed scheme performs well when interference is high, and optimally when interference is low.

     

    In the second part, we introduce cooperation to utilize the otherwise idle BSs and mitigate same- and other entity interference. Zero forcing (ZF) is employed in the downlink where not only downlink UEs but also uplink BSs are included in the precoding. Since downlink BSs do not know the information to be sent by uplink UEs beforehand, dummy symbols with zero power are transmitted. It shown that both uplink and downlink performance improves at low and medium load. Furthermore, it is possible to trade performance in the two directions at high load.

  • Presentation: 2017-10-27 13:30 Rum 3085, L-huset, Stockholm
    Håkansson, Martin
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning. Lantmäteriet.
    Hardware biases and their impact on GNSS positioning2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    GNSS hardware biases appear in code and phase observations, and originates both from the receiver and satellite hardware. These biases influence the accuracy in precise GNSS positioning if not handled properly.

    This thesis is based on two papers, where one is a review paper published in GPS Solutions, and the other is a research paper currently in review (resubmitted after minor revision) for Journal of Geodetic Science. The first paper compiles current results and gives an overview of those situations where biases are of the greatest importance for precise positioning. The second paper investigates the satellite dependency in two cases of relative phase biases.

    In the first paper, a review is given on how hardware biases influence precise GNSS positioning in various situations. These can roughly be divided into five cases: positioning not employing the ionosphere free combination to which the satellite clock corrections are aligned, GNSS based ionospheric modeling, determination of the phase ambiguity as an integer in PPP, and positioning with GLONASS.

    In the second paper, the satellite dependency for two cases of relative phase biases are investigated: relative between-receiver biases in single differenced phase observations from two receivers, relative between-signals biases in observation differences between two signals recorded by the same receiver and associated with the same carrier frequency. In both these cases a satellite dependency was discovered. The first case showed a difference of 0.8 mm between the greatest and smallest values, while the corresponding difference in the second case was 3.5 mm.

    It was also discovered that the biases in the first case varied periodically over time, and with a period of one sidereal day. The exact cause for these variations could however not be determined in the experiment, even though multipath could be excluded as their source.

  • Presentation: 2017-10-27 14:00 Q2, Stockholm
    Schillinger, Philipp
    KTH, School of Electrical Engineering (EES), Automatic Control. Bosch Center for Artificial Intelligence.
    Specification Decomposition and Formal Behavior Generation in Multi-Robot Systems2017Licentiate thesis, monograph (Other academic)
    Abstract [en]

    While autonomous robot systems are becoming increasingly common, their usage is still mostly limited to rather simple tasks. This primarily results from the need for manually programming the execution plans of the robots. Instead, as shown in this thesis, their behavior can be automatically generated from a given goal specification. This forms the basis for providing formal guarantees regarding optimality and satisfaction of the mission goal specification and creates the opportunity to deploy these robots in increasingly sophisticated scenarios. Well-defined robot capabilities of comparably low complexity can be developed independently from a specific high-level goal and then, using a behavior planner, be automatically composed to achieve complex goals in a verifiably correct way. Considering multiple robots introduces significant additional planning complexity. Not only actions need to be planned, but also allocation of parts of the mission to the individual robots needs to be considered. Classically, either are planning and allocation seen as two independent problems which requires to solve an exponential number of planning problems, or the formulation of a joint team model leads to a product state space between the robots. The resulting exponential complexity prevents most existing approaches from being practically useful in more complex and realistic scenarios. In this thesis, an approach is presented to utilize the interplay of allocation and planning, which avoids the exponential complexity for independently executable parts of the mission specification. Furthermore, an approach is presented to identify these independent parts automatically when only being given a single goal specification for the team. This bears the potential of improving the efficiency to find an optimal solution and is a significant step towards the application of formal multi-robot behavior planning to real-world problems. The effectiveness of the proposed methods is therefore illustrated in experiments based on an existing office environment and in realistic scenarios.

  • Presentation: 2017-11-09 10:15 L1, Stockholm
    Held, Manne
    KTH, School of Electrical Engineering (EES), Automatic Control. KTH, School of Industrial Engineering and Management (ITM), Centres, Integrated Transport Research Lab, ITRL.
    Optimal Speed and Powertrain Control of a Heavy-Duty Vehicle in Urban Driving2017Licentiate thesis, monograph (Other academic)
    Abstract [sv]

    A major challenge in the transportation industry is how to reduce the emissions of greenhouse gases. One way of achieving this in vehicles is to drive more fuel-efficiently. One recently developed technique that has been successful in reducing the fuel consumption is the look-ahead cruise controller, which utilizes future conditions such as road topography. In this this thesis, similar methods are used in order to reduce the fuel consumption of heavy-duty vehicles driving in environments where the required and desired velocity vary. The main focus is on vehicles in urban driving, which must alter their velocity due to, for instance, changing legal speed restrictions and the presence of intersections. The driving missions of such vehicles are here formulated as optimal control problems. In order to restrict the vehicle to drive in a way that does not deviate too much from a normal way of driving, constraints on the velocity are imposed based on statistics from real truck operation.

    In a first approach, the vehicle model is based on forces and the cost function involves the consumed energy. This problem is solved both offline using Pontryagin's maximum principle and online using a model predictive controller with a quadratic program formulation. Simulations show that 7 % energy can be saved without increasing the trip time nor deviating from a normal way of driving.

    In a second approach, the vehicle model is extended to include an engine and a gearbox with the objective of minimizing the fuel consumption. A fuel map for the engine and a polynomial function for the gearbox losses are extracted from experimental data and used in the model. This problem is solved using dynamic programming taking into consideration gear changes, coasting with gear and coasting in neutral. Simulations show that by allowing the use of coasting in neutral gear, 13 % fuel can be saved without increasing the trip time or deviating from a normal way of driving.

    Finally, an implementation of a rule-based controller into an advanced vehicle model in highway driving is performed. The controller identifies sections of downhills where fuel can be saved by coasting in neutral gear.

  • Presentation: 2017-11-10 10:30 F3, Stockholm
    Brodén, Daniel A.
    KTH, School of Electrical Engineering (EES), Electric Power and Energy Systems.
    Modeling and Simulations of Demand Response in Sweden2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Electric power systems are undergoing a paradigm shift where an increasing number of variable renewable energy resources such as wind and solar power are being introduced to all levels of existing power grids. At the same time consumers are gaining a more active role where self energy production and home automation solutions are no longer uncommon. This challenges traditional power systems which were designed to serve as a centralized top-down solution for providing electricity to consumers. Demand response has risen as a promising solution to cope with some of the challenges that this shift is creating. In this thesis, control and scheduling studies using demand response, and consumer load models adapted to environments similar to Sweden are proposed and evaluated. The studies use model predictive control approaches for the purpose of providing ancillary and financial services to electricity market actors using thermal flexibility from detached houses. The approaches are evaluated on use-cases using data from Sweden for the purpose of reducing power imbalances of a balance responsible player and congestion management for a system operator. Simulations show promising results for reducing power imbalances by up to 30% and managing daily congestion of 5-19 MW using demand response. Moreover, a consumer load model of an office building is proposed using a gray-box modeling approach combining physical understanding of buildings with empirical data. Furthermore, the proposed consumer load model along with a similar model for detached houses are packaged and made freely available as MATLAB applications for other researchers and stakeholders working with demand response. The applications allow the user to generate synthetic electricity load profiles for heterogeneous populations of detached houses and office buildings down to 1-min resolution. The aim of this thesis has been to summarize and discuss the main highlights of the included articles. The interested reader is encouraged to investigate further details in the second part of the thesis as they provide a more comprehensive account of the studies and models proposed.

  • Presentation: 2017-11-10 11:00 Sal A (Sal östen Mäkitalo), Stockholm
    Hossain, Mohammad Istiak
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Designing Efficient Access Control to Comply Massive-Multiservice IoT over Cellular Networks2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Internet of Things (IoT) has come in reality to improve our living quality. Automation is embraced in all the possible business verticals that have diverse communication needs ranged from static devices’ sporadic transmission to mobile devices’ every minute transmission. Despite, there are many technologies available today to support IoT services; cellular systems can play a vital role for IoT services, like wearables, vehicular, and industrial IoT, rollout which have either mobility or security concern. 

    IoT services generated traffic are foreseen as a sporadic-bursty traffic. As the cellular networks are designed to serve continuous data traffic, the existing system’s access control mechanism cannot efficiently conform to the burstiness of traffic. This limits the scope of the network scalability in terms of simultaneous serving devices’ capacity. Also, this bursty pattern can extensively increase the rate of network’s congestion incident. In this thesis, we focus on these underlying challenges to support a large number of heterogeneous IoT services with existing services over the same radio network. An important question for supporting IoT services over cellular networks is how detrimental are the effects of IoT services on other services of cellular networks. This dissertation seeks to answer this with quantitative results to indicate the real constraints of existing networks.

    An important conclusion is that existing cellular system is incompetent to support the bursty arrival of massive IoT devices in terms of radio networks’ access control plane’s scalability. Therefore, this dissertation presents solutions to overcome the identified limitations of access control planes. To improve the performance of the access control plane, we incorporate a vertical core network controlled group management scheme that can assure the operator’s granular control over capillary gateways. Besides, this introduces a unique handover opportunity between cellular and capillary network vertices. Then, we present a simple but efficient initial access mechanism to overcome the initial access collision at the very early stage. Finally, we show the impact of access collision and retransmission on the initial access resource dimensioning.We present a practical traffic model that is realistic for the traffic scenario for mixed-traffic. Our presented results and analysis depict the trade-offs between access rate, retransmission and resource allocation over time and frequency.Our results reveal that with proposed schemes of the cellular system’s access control plane can be scalable and resilient to accommodate a large number of IoT devices without incurring extra delay or need of resources to the system.

  • Presentation: 2017-11-23 10:00 K52, Stockholm
    Josefsson, Leila
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Bioanalytical separation using capillary electrophoresis: Applications with microbubbles and proteins2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis the possibilities of using capillary electrophoresis as a separation technique for analysis of proteins and microbubbles is presented.

    A complete analytical process consists of five necessary steps of which one is the actual analysis step. For this step a suitable analytical technique is needed. Capillary electrophoresis (CE) is one of the common analytical separation techniques used for analysis of a diversity of analytes, and can be both used in routine analysis and for research purposes. The reason for using CE, compared to other liquid-based separation techniques, is mainly short analysis time, high resolution, and negligible sample volumes and solvent waste. Depending on the characteristics of the analytes, and the sample matrix, different modes of CE can be used, where capillary zone electrophoresis (CZE) is the most employed one. The basic principle of CZE is separation of the analytes due to differences in total mobility, which is dependent on the charge and size of the analytes, and the electroosmotic flow (EOF). The EOF can be controlled by several parameters e.g. choice of background electrolyte (BGE), and the optimization of the parameters has been discussed throughout the thesis.

    To improve the properties of the BGE, an ethylammonium nitrate (EAN) water solution was used as BGE for CE analysis in Paper I. The precision of the EOF with this method was determined by adjusting the pH of the BGE, the concentration of EAN in the BGE, and the electric field. Model proteins were thereafter analysed using the optimal parameters yielding a precision sufficient for routine control.

    One example of the applications of CE is separation of novel contrast agents, which consist of polyvinyl alcohol microbubbles (PVA-MBs). In Paper II, a method for analysis of PVA-MBs in biological samples using CE with UV-detection was developed. It was also established that intact PVA-MBs could be distinguished from ultrasound degraded PVA-MBs in the same set-up.

    The full text will be freely available from 2018-11-23 12:00