Now showing items 1-20 of 116

    • 6G Network Architecture Using FSO-PDM/PV-OCDMA System with Weather Performance Analysis 

      Singh, Mehtab; Pottoo, Sahil Nazir; Armghan, Ammar; Aliqab, Khaled; Alsharari, Meshari; Abd El-Mottaleb, Somia A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-11-04)
      This paper presents a novel 160 Gbps free space optics (FSO) communication system for 6G applications. Polarization division multiplexing (PDM) is integrated with an optical code division multiple access (OCDMA) technique to form a PDM-OCDMA hybrid. There are two polarization states: one is X-polarization generated from adjusting the azimuthal angle of a light source at 0° while the other is ...
    • 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 ...
    • Advanced Model Predictive Control Algorithm for Inverters as a Low-cost Solution in ZynQ 

      Hoff, Bjarte (Conference object; Konferansebidrag, 2016)
    • 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 ...
    • Approaches to learning of linear algebra among engineering students 

      Rensaa, Ragnhild Johanne (Peer reviewed; Bok; Book; Bokkapittel; Chapter, 2017-02)
      The present paper investigates engineering students` own descriptions of what they mean by learning of linear algebra and how they know that they have learned something. I seek to extract keywords from engineering students` descriptions of learning of this discipline by drawing on grounded theory techniques and classifying the answers in conceptual and procedural approaches. By this, both detailed ...
    • Assessment considerations during lockdown in Norway: An exploratory case study with focus on misconducts in university mathematics 

      Rensaa, Ragnhild Johanne (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-05-11)
      The present paper raises a discussion about assessment formats in mathematics courses at Norwegian universities during the Covid lockdown. This proved to be challenging since the European GDPR regulations are strictly interpreted in Norway, making proctoring at home difficult. Based on analyses of nine university teachers’ feedback on how exams were carried out at their university during lockdown, ...
    • Attitude Determination and Control System for Satellites in Elliptical Orbits - a Complete Solution 

      Oland, Espen (Konferansebidrag; Conference object, 2017-08-08)
      This paper presents a complete solution to the problem of attitude determination and control for satellites in elliptical orbits. Specifically, it shows how to create the orbital mechanics, account for perturbing gravity torques, create a nonlinear PD+ attitude controller, map the control signal to desired thrust firings, implement magnetic field and Sun vector models, and how to implement a Madgwick ...
    • Autonomous Inspection of the International Space Station 

      Oland, Espen (Konferansebidrag; Conference object, 2017-09-18)
      This paper presents a solution to autonomous inspection of the international space station using a rigid spacecraft. Specifically, the paper presents the orbital mechanics, formation dynamics as well as rotational dynamics required to control the spacecraft relative to the space station, and then presents two PD+ controllers enabling a spacecraft to track a series of waypoints while pointing a sensor ...
    • Bio‐inspired hybrid BFOA‐PSO algorithm‐based reactive power controller in a standalone wind‐diesel power system 

      Wagle, Raju; Sharma, Pawan; Charu, Sharma; Gjengedal, Terje; PRADHAN, CHITTARANJAN (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-01-05)
      With an increase in the penetration of renewable energy sources such as wind into the power systems, the operation and control of voltage/reactive power have become more complicated and challenging than ever. As a result, the reactive power imbalance between reactive power generation and demand instigates a reduction in system voltage stability. To deal with the aforesaid scenarios, automatic voltage ...
    • Cascade-Based Controlled Attitude Synchronization and Tracking of Spacecraft in Leader-Follower Formation 

      Schlanbusch, Rune; Nicklasson, Per Johan; Loria, Antonio (Journal article; Peer reviewed; Tidsskriftartikkel, 2011)
    • Cascade-Based Controlled Attitude Synchronization and Tracking of Spacecraft in Leader-Follower Formation 

      Schlanbusch, Rune; Loria, Antonio; Nicklasson, Per Johan (Journal article; Tidsskriftartikkel; Peer reviewed, 2011-05-05)
      We propose controllers for leader-follower attitude synchronization of spacecraft formations in the presence of disturbances, that is, the leader spacecraft is controlled to follow a given reference, while a follower spacecraft is controlled to synchronize its motion with the leader’s. In the ideal disturbance-free scenario, we show that synchronization takes place asymptotically. Moreover, we ...
    • Cascaded Model Predictive Control of Grid Connected Converter with LCL Filter 

      Hoff, Bjarte (Peer reviewed; Book; Chapter, 2018-12-31)
      This paper presents a control strategy for grid connected voltage source converters with LCL filter, based on a cascade of two model predictive controllers (MPC). Despite the attention MPC has received in the research community over the last years, there are still raised question about what advantages such control methods can offer, compared to existing established control strategies. The cascaded ...
    • Characteristics of fragmented aurora-like emissions (FAEs) observed on Svalbard 

      Dreyer, Joshua; Partamies, Noora; Whiter, Daniel; Ellingsen, Pål Gunnar; Baddeley, Lisa; Buchert, Stephan C. (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-04)
      This study analyses the observations of a new type of small-scale aurora-like feature, which is further referred to as fragmented aurora-like emission(s) (FAEs). An all-sky camera captured these FAEs on three separate occasions in 2015 and 2017 at the Kjell Henriksen Observatory near the arctic town of Longyearbyen, Svalbard, Norway. A total of 305 FAE candidates were identified. They seem to appear ...
    • Charging technology for small maritime vessels 

      Hoff, Bjarte (Conference object, 2019-01-21)
    • A Class-E-Based Resonant AC-DC Converter With Inherent PFC Capability 

      Al-Sallami, Hussein; M. Ammar, Ahmed; Nour, Yasser; A. E. Andersen, Michael (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-22)
      This paper investigates the use of the class-E inverter for power factor correction (PFC) applications. Analytical and state-space models are derived showing the class-E inverter’s capability of achieving inherent PFC operation with a constant duty cycle. The inherent PFC operation limits the controller responsibility to the regulation of the output voltage, which is key for resonant converters with ...
    • Classification of Bulk Cargo Types Stored Openly at Ports Using CNN 

      Koirala, Madhu; Ellingsen, Pål Gunnar; Ådland, Roar Os (Chapter; Bokkapittel, 2023)
      In this paper, we present a novel concept of tracking cargoes at open ports using remote sensing images and convolution neural network (CNN) to classify various dry bulk commodities. The dataset used is prepared using Sentinel-2 atmospherically corrected (Sentinel-2 L2A) images covering 12 spectral bands. There are total 4995 labeled and geo-referenced images for four different cargoes-bauxite, ...
    • Classification of bulk cargo types stored openly at ports using CNN 

      Koirala, Madhu; Ellingsen, Pål Gunnar; Ådland, Roar Os (Chapter; Bokkapittel, 2023-10-20)
      In this paper, we present a novel concept of tracking cargoes at open ports using remote sensing images and convolution neural network (CNN) to classify various dry bulk commodities. The dataset used is prepared using Sentinel-2 atmospherically corrected (Sentinel-2 L2A) images covering 12 spectral bands. There are total 4995 labeled and geo-referenced images for four different cargoes-bauxite, coal, ...
    • A Co-simulation Procedure for Optimal Reactive Power Control in Active Distribution Networks 

      Tricarico, Gioacchino; Wagle, Raju; Martinez, Jesus Castro; Gonzalez-Longatt, Francisco; Dicorato, Maria; Forte, Giusenne; Rueda, Jose Luis (Chapter; Bokkapittel, 2023)
      Distribution grids are subject to a drastic evolution in their operating conditions due to the high integration of renewable energy resources (RES) and their ability to regulate voltage. To cope with this issue, modern solar photovoltaic (PV) systems are equipped with smart inverters enabled with communication capabilities that allow the coordinated operation to offer services such as controlling ...
    • Co-simulation-based optimal reactive power control in smart distribution network 

      Wagle, Raju; Pham, Le Nam Hai; Tricarico, Gioacchino; Sharma, Pawan; Rueda, Jose Luis; Gonzalez-Longatt, Francisco (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-30)
      The increasing integration of distributed energy resources such as photovoltaic (PV) systems into distribution networks introduces intermittent and variable power, leading to high voltage fluctuations. High PV integration can also result in increased terminal voltage of the network during periods of high PV generation and low load consumption. These problems can be solved by optimal utilization ...
    • Comparative Analysis of Deep Learning and Statistical Models for Air Pollutants Prediction in Urban Areas 

      Naz, Fareena; McCann, Conor; Fadim, Muhammad; Cao, Tuan-Vu; Hunter, Ruth; Nguyen, Trung Viet; Nguyen, Long D.; Duong, Trung Q. (Journal article; Tidsskriftartikkel, 2023-06-23)
      Rapid growth in urbanization and industrialization leads to an increase in air pollution and poor air quality. Because of its adverse effects on the natural environment and human health, it’s been declared a “silent public health emergency”. To deal with this global challenge, accurate prediction of air pollution is important for stakeholders to take required actions. In recent years, deep learning-based ...