Recent additions

  • Electric Ships in Norway - Experiences and Future trends. 

    Hoff, Bjarte (Conference object; Konferansebidrag, 2020)
  • Adaptive Backstepping Control for a Fully-Actuated Rigid-Body in a Dual-Quaternion Framework 

    Andersen, Tom Stian; Kristiansen, Raymond (Chapter; Bokkapittel, 2020-03-12)
    We address the trajectory tracking problem for a fully actuated rigid-body with unknown mass and inertia parameters and unknown disturbance forces, using an adaptive backstepping controller based on dual-quaternions. We show that the proposed controller, in closed loop with a nonlinear model of the system, renders the equilibrium points uniformly asymptotically stable. The proposed controller ...
  • Reactive-Based Position Control of an Underactuated Quadrotor 

    Andersen, Tom Stian; Kristiansen, Raymond (Chapter; Bokkapittel, 2020-07-20)
    This paper addresses the problem of position control or waypoint tracking for an underactuated quadrotor. The proposed control law is what is known as reaction based in the way that the attitude system reacts to errors in the translational motion. This methodology requires no generation of desired attitude or angular velocity and the resulting control law is model-independent in that it does ...
  • First-year engineering students’ mathematics task performance and its relation to their motivational values and views about mathematics 

    Tossavainen, Timo; Rensaa, Ragnhild Johanne; Haukkanen, Pentti; Mattila, Mika; Johansson, Monica (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-26)
    This study investigates Finnish, Norwegian, and Swedish first-year engineering students’ task performance in mathematics and examines how it relates to their motivational values and beliefs about the nature of mathematics. In a set of seven mathematical tasks, female students outperformed male students, for example, in the simplification of symbolic expressions. Our findings also show that ...
  • Perspectives and reflections on teaching linear algebra 

    Rensaa, Ragnhild Johanne; Hogstad, Ninni Marie; Monaghan, John David (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-03)
    This paper presents ‘expert opinions’ on what should be taught in a first-year linear algebra course at university; the aim is to gain a generic picture and general guiding principles for such a course. Drawing on a Delphi method, 14 university professors—called ‘experts’ in this study—addressed the following questions: What should be on a first-year linear algebra undergraduate course for engineering ...
  • Coordinated Power Management and Control of Standalone PV-Hybrid System with Modified IWO-Based MPPT 

    Pradhan, Chittaranjan; Senapati, Manoj Kumar; Malla, Siva Ganesh; Nayak, Paresh Kumar; Gjengedal, Terje (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-14)
    To augment the photovoltaic (PV) power generation conversion, a maximum power point tracking (MPPT) technique plays a very significant role. This article introduces a hybrid MPPT algorithm integrating modified invasive weed optimization (MIWO) and perturb and observe (P&O) technique under the rapid weather change and partial shading scenarios for the efficient extraction of the maximum power from ...
  • Building a Low-Cost Ground Station for Weather Satellite Image Reception 

    Zahid, Ezzatullah (Master thesis; Mastergradsoppgave, 2019-06-27)
    In this Thesis, a small, low-cost, portable and easily deployable ground station was built, to track and receive signals from National Oceanic and Atmospheric Administration (NOAA) weather satellites (series 15, 18 and 19) in VHF and UHF bands, process and convert these to images are presented. A ground station, capable of receiving reasonably good quality images from NOAA weather satellites was ...
  • Application of electric vehicle charging solutions on small maritime vessels 

    Mandasari, Maya (Master thesis; Mastergradsoppgave, 2019-06-28)
    This thesis explores various charging standards for electric vehicles with the goal to find a standard that can be implemented in an electric maritime vessel (EMV). Combined charging system 2.0 (CCS2) is selected and the standard is explained in detail along with the necessary power electronics. Several Matlab and dSPACE simulations is made to test the charging and communication. A laboratory ...
  • Wireless Charging for Small Electric Vessels 

    Omosanya, Hafeez Abolade (Master thesis; Mastergradsoppgave, 2019-06-28)
    With the presence of traditional thick and heavy cables for charging, the risk of humans exposed to high-voltage, and due to mechanical wear and tear in conductive materials, inductive wireless charging was introduced which is the future of charging technology. This project has focused on magnetic-coupled wireless transfer with some key components involved such as a DC voltage source, a full-bridge ...
  • HVDC Transmission and Energy Storage for Wind Power Plant 

    Moe, Torgeir (Master thesis; Mastergradsoppgave, 2019-06-28)
    This thesis will investigate the effects of an energy storage system incorporated into the submodules of a modular multilevel converter connected to a HVDC line. A simulation has been made to see the effects of energy storage on the transmission of power from a generator connected to the grid via a HVDC line with two MMCs connected in each end, one of which incorporates the energy storage system.
  • Design and construction of a half-bridge using wide-bandgap transistors 

    Vatshelle, Fredrik Hausvik (Master thesis; Mastergradsoppgave, 2019-06-28)
    A continuously increasing demand of electric power makes energy efficiency imperative in modern technology. The transistor is considered as the fundamental element of modern electronic products.
  • Sol vinkel estimator. Solpanel rig med dobbel akse orientering 

    Mikkelsen, Rolf Olaf (Master thesis; Mastergradsoppgave, 2019-06-28)
    Denne rapporten presenterer design og simuleringer av en toakset solcellerigg. Denne bestpunktsporingen riggen fungerer utelukkende basert på utgangseffekten til solcellepanelet montert til det. Det bruker ikke noen solsensor til å orientere solcellepanelet. Posisjonen til solen er beregnet basert på tid og stedsinformasjon. Siden dette solpanelet vil bli montert her på UiT, Norges Arktiske Universitet, ...
  • Energy storage technologies from a power system point of view 

    Wang, Raymond Klippenvåg (Master thesis; Mastergradsoppgave, 2019-06-28)
    This thesis presents energy storage technologies, as well as their most applicable ways of integration into the power system. The storage technologies provided are relevant in regards to ancillary services, peak shaving, energy arbitrage and not least integration in combination with intermittent renewable production. A grid analysis was performed to determine the obvious differences between different ...
  • Themes within lecturers' views on the teaching of linear algebra 

    Rensaa, Ragnhild Johanne; Hogstad, Ninni Marie; Monaghan, John David (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-09-25)
    This paper reports on themes that arose in an investigation of university lecturers’ views on the teaching of linear algebra. This focus on themes was the initial part of a study concentrating on four areas: What is important to teach in a first course in linear algebra? Are there teaching methods which are particularly suited for such a course? Are there tools that should/should not be used; and ...
  • Swedish first-year engineering students’ views of mathematics, self-efficacy and motivation and their effect on task performance 

    Tossavainen, Timo; Rensaa, Ragnhild Johanne; Johansson, Monica (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-29)
    We examine a group (N = 88) of Swedish first-year engineering students, their motivation, self-efficacy, and beliefs about the nature of mathematics, and how these relate to their task performance in mathematics. In our data, engineering students who emphasized the exact reasoning in their view of mathematics performed significantly better in a set of mathematical tasks than those who emphasized ...
  • Dual quaternion control: a review of recent results within motion control 

    Johansen, Tor-Aleksander; Sánchez, José J.; Kristiansen, Raymond (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-11-24)
    This paper presents a review of recent results in the field of dual quaternion based motion control. In addition, we derive two control laws for trajectory tracking control of a fully actuated rigid-body based on the resemblance of dual quaternion kinematics and dynamics to the quaternion based rotational kinematics and dynamics. A velocity error sliding surface and an integrator backstepping ...
  • Preliminary Results on Waypoint Tracking for Spacecraft with Actuator Constraints 

    Oland, Espen; Andersen, Tom Stian (Peer reviewed; Chapter; Bokkapittel, 2019-07-22)
    This paper presents preliminary results on how to perform waypoint tracking with spacecraft with actuator constraints. It considers a simplified spacecraft model and can be considered a deep space model, and shows how to perform waypoint tracking with only one main thruster together with full attitude control. As the spacecraft reaches close to the waypoint during a deceleration phase that makes the ...
  • Controlling a Chain of Integrators with Constrained Actuation Using Exponential Activation Functions 

    Oland, Espen; Kristiansen, Raymond (Peer reviewed; Chapter; Bokkapittel, 2019-10-24)
    This paper shows how to control a chain of integrators with constrained actuation by using exponential activation functions. Specifically, it shows how the control law can be decomposed into several parts that can be activated as they are required, resulting in a simple control law that is able to make the states converge fast to zero.
  • Ant colony optimization and analysis of time step resolution in transmission expansion computations for wind power integration 

    Fuchs, Ida; Gjengedal, Terje (Chapter; Bokkapittel, 2011)
    This paper investigates the necessary time step resolution in a transmission expansion planning algorithm based on ant colony optimization. A maximal and efficient wind power integration is the main motivation for the grid expansion, which requires a planning tool dealing with wind energy fluctuations. For the analysis a power system model for the Nordic area is used, including a wind power ...
  • PD+ based trajectory tracking of the underactuated quadrotor platform using dual quaternions 

    Johansen, Tor-Aleksander; Andersen, Tom Stian; Kristiansen, Raymond (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-29)
    We address the problem of state feedback trajectory tracking of the underactuated quadrotor platform in the dual quaternion framework through a PD+ tracking controller. The control law negates the need of generating a desired attitude trajectory as the translational error is mapped directly onto the rotational actuators through a virtual frame. More precisely, we show uniform practical asymptotic ...

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