Now showing items 84-103 of 191

    • Home Load Disaggregation using Deep Learning and Bayesian Optimization: A Case Study in Arctic Climate in Northern Norway 

      Kianpoor, Nasrin; Hoff, Bjarte; Østrem, Trond (Chapter; Bokkapittel, 2023-08-03)
      Load monitoring is an essential task in energy management systems. In this paper, an approach that relies on a long short-term memory (LSTM) model and a discrete wavelet transform (DWT) filter is presented to estimate the energy usage of flexible appliances. In the preprocessing stage, the main features of the aggregated power signal are extracted using DWT. Deep learning methods are very sensitive ...
    • 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.
    • Impact of Inverter Based Resources on System Stability in Low Inertia Power System Network 

      Zafar Raja, Hasnain (Master thesis; Mastergradsoppgave, 2023-05-20)
      Inverter-based resources (IBRs), such as solar and wind power are gaining popularity because of their increasing acceptance, environmental benefits and decreasing costs. However, their integration into power systems can lead to significant impacts on system inertia and frequency stability, which are crucial for maintaining the reliability of the power grid. In traditional power systems, the synchronous ...
    • Improving Geopolymer Characteristics with Addition of Poly-Vinyl Alcohol (PVA) Fibers 

      Ekaputri, Januarti Jaya; Fujiyama, Chikako; Chijiwa, Nobuhiro; Ho, Tu Dac; Nguyen, Hung Thanh (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-20)
      This paper presents the benefits of PVA fibers in improving the mechanical properties of class F fly-ash-based geopolymer concrete. The activator used in the geopolymer was 8M sodium hydroxide (NaOH) and sodium silicate (Na<sub>2</sub>SiO<sub>3</sub>), with a mass ratio of Na<sub>2</sub>SiO<sub>3</sub> to NaOH varied from 1.5 to 2.5. Cylindrical specimens with a diameter of 100 mm and a height of ...
    • Ingeniørstudenters bruk av læringsverktøy i et lineær algebraemne : hvilken rolle spiller nettbaserte forelesninger? 

      Rensaa, Ragnhild Johanne (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-11)
      I denne artikkelen diskuteres studentenes bruk av læringsverktøy med spesielt fokus på et nettbasert tilbud. Egne forelesninger i et emne i lineær algebra for master ingeniørstudenter, fjerde år, har blitt streamet og publisert, og jeg har undersøkt hvordan studentene har brukt disse forelesningene. Data er innsamlet første og tredje gang dette ble gjort, og hovedvekten i denne artikkelen er lagt ...
    • Innvirkninger av distribuert produksjon i svake distribusjonsnett, lokalisert i nordområdene. Hvordan påvirker plusskunder det omkringliggende lavspente distribusjonsnettet. 

      Johannessen, Leif Inge Krogstad (Master thesis; Mastergradsoppgave, 2018-08-16)
      I denne rapporten har virkninger av plusskunder i svake, lavspente distribusjonsnett blitt undersøkt. Gjennom en informasjonsinnsamling, ble de største utfordringer for fremtidige plusskunder identifisert. Herunder aktuelle teknologier, energiresuser, regelverk og tekniske forhold. Det ble undersøkt hvilke utfordringer et nettselskap kan forvente seg, ved introduksjon av lokal produksjon i et ...
    • Integrating sensors for robots operating on offshore oil and gas platforms 

      Tolue, Shabnam (Master thesis; Mastergradsoppgave, 2023-05-21)
      This thesis presents a solution to integrate sensors and instruments on a robot to be used instead of operators on unmanned oil and gas offshore platforms. Operators have various tasks from inspection to maintenance in the platforms. Because of high costs of having operators in offshore platforms, there has been always an ambitious to design a fully unmanned automated platform to decrease the costs ...
    • Integration of UTM and U-Space on Norwegian continental shelf 

      Isdahl, Morten Andersen (Master thesis; Mastergradsoppgave, 2022-05-16)
      In this master thesis, we present an overview of the U-Space and Regulations in Europe, while also taking into consideration the progression of the integration of both parts in Norwegian airspace over the Norwegian continental shelf. This thesis is mainly separated into three parts. The first part is taking a look into the European Union's roadmap/plan for establishing an Unmanned Aircraft System ...
    • Interpreting teaching for conceptual and for procedural knowledge in a teaching video about linear algebra 

      Rensaa, Ragnhild Johanne; Vos, Pauline (Journal article; Tidsskriftartikkel, 2018)
      The aim of this study is to investigate teaching videos about mathematics, seeking to uncover research-based foundations for their quality. By drawing on the notions of procedural and conceptual knowledge, the research was operationalized by asking professionals in undergraduate mathematics education (n=18) to interpret sections of a teaching video. The video dealt with a topic in linear algebra. ...
    • Investigation of ballast water conditions using remote sensing. Suspended Particulate Matter Characterization in Emden Sea Port 

      Taña i Viñeta, Pau (Master thesis; Mastergradsoppgave, 2023-05-22)
      This thesis investigates the use of remote sensing techniques to study the conditions of ballast water in the northwestern port of Emden, Germany. Sentinel-2 data of the seaport has been collected and used in order to retrieve the suspended particulate matter (SPM), evaluating its distribution and checking for any time or spatial periodicity over the past 5 years. The aim of the study is to provide ...
    • Investigation of wireless electrification for a reconfigurable manufacturing cell 

      Al-Sallami, Hussein Mahdi Yaseen; Arnarson, Halldor; Solvang, Bjørn; Bremdal, Bernt Arild (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-24)
      Reconfigurable manufacturing systems (RMS) with a rearrangeable structure can quickly adjust their productivity to meet the dynamic market changes and the demand for high-variety products. Industry 4.0 technologies have enhanced the RMS flexibility and made the automation of the reconfiguration of the manufacturing system possible. As an Industry 4.0 technology, wireless power transfer (WPT) can ...
    • Investigation of wireless electrification for a reconfigurable manufacturing cell 

      Al-Sallami, Hussein Mahdi Yaseen; Arnarson, Halldor; Solvang, Bjørn; Bremdal, Bernt Arild (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-24)
      Reconfigurable manufacturing systems (RMS) with a rearrangeable structure can quickly adjust their productivity to meet the dynamic market changes and the demand for high-variety products. Industry 4.0 technologies have enhanced the RMS flexibility and made the automation of the reconfiguration of the manufacturing system possible. As an Industry 4.0 technology, wireless power transfer (WPT) can ...
    • Keeping track of samples in multidisciplinary fieldwork 

      Ellingsen, Pål Gunnar; Ferrighi, Lara; Godøy, Øystein Arne; Gabrielsen, Tove M. (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-11-10)
      We here present methods, tools and results for efficiently collecting metadata and tracking samples collected in the field. The samples and metadata were collected during scientific cruises conducted by amongst others marine biologists, oceanographers, geochemists and marine geologists in the Nansen Legacy project. It is here reported on the successful development and implementation of a system ...
    • Large-scale Wind Power Integration in Northern Norway 

      Singh, Arwinder (Master thesis; Mastergradsoppgave, 2018-08-16)
      Norway has very high flexibility in energy production since hydropower covers about 95% of yearly energy demand. It is best to have a combination of wind and hydropower and hence it applies perfectly here in Norway. The performance of the wind farm can be significantly enhanced by employing full-capacity converters. The state-of-the-art literature study has been done on Squirrel Cage Induction ...
    • Load modeling from smart meter data using neural network methods 

      Kianpoor, Nasrin; Hoff, Bjarte; Østrem, Trond (Chapter; Bokkapittel, 2021)
      Electricity load modeling plays a critical role to conduct load forecasting or other applications such as non-intrusive load monitoring. For such a reason, this paper investigates a comparison study of two common artificial neural network methods (Multilayer perceptron (MLP) and radial basis function neural network (RBF-NN) for home load modeling application. The accuracy of load modeling using ...
    • Maximum Available Power of Undersea Capacitive Coupling in a Wireless Power Transfer System 

      Al-Sallami, Hussein; Hoff, Bjarte; Østrem, Trond (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-06-23)
      This paper studies the maximum available power of a dissipative capacitive power transfer (CPT) system submerged in seawater. The CPT system's maximum power capability is driven using the network theory, precisely the conjugate-image approach. The equations of the maximum available load power and the system's corresponding efficiency are expressed as a function of the capacitive coupling parameters. ...
    • Mode division multiplexing free space optics system with 3D hybrid modulation under dust and fog 

      Pottoo, Sahil Nazir (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-08-13)
      Mode division multiplexing (MDM) is an emerging information transmission technique in which multiple data signals can be transmitted simultaneously on different modes of a single wavelength laser beam over a free-space channel. MDM is a potential technique for the realization of high-speed spectral efficient communication links for future generations of wireless networks. We present a novel MDM-based ...
    • Modeling and analysis of power system oscillations using real-time simulator. 

      Sandberg, Andreas (Master thesis; Mastergradsoppgave, 2022-05-16)
      In this thesis a version of the Kundur two-area model has been developed for Simulink and real time simulator software and hardware from OPAL-RT. This model should be used for testing the rotor angle oscillations load variations create. A review of the different control elements found in basic power systems has been reviewed and implemented. The main component that will be manipulated in the model ...
    • Modeling and Analyzing of Inverters for Controlling Voltage and Frequency in an Islanded Microgrid 

      Khan, Mazhar Ali (Master thesis; Mastergradsoppgave, 2021-05-18)
      Recently, the growth of inverter-based generations (IBGs) like solar photovoltaic (PV) and wind turbine generators in the form of microgrids (MGs) has been increasing. However, control of voltage and frequency becomes a challenging task for MGs especially when they operate in an islanded mode, due to the inherent low-inertia feature of IBGs compared to a grid-tied mode where there is a grid support. ...
    • Modeling and Attitude Control of Satellites in Elliptical Orbits 

      Oland, Espen (Peer reviewed; Chapter, 2018-11-05)
      The attitude determination and control system (ADCS) for spacecraft is responsible for determining its orientation using sensor measurements and then applying actuation forces to change the orientation. This chapter details the different components required for a complete attitude determination and control system for satellites moving in elliptical orbits. Specifically, the chapter details the orbital ...