Now showing items 248-267 of 919

    • 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 ...
    • Energy, Exergy, And Environmental Assessment Of A Small-Scale Solar Organic Rankine Cycle Using Different Organic Fluids 

      Polanco Pinerez, Geanette; Ochoa, Guillermo Valencia; Duarte-Forero, Jorge (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-09)
      This article presents an energetic, exergetic, and environmental (3E) analysis of a solar powered simple Rankine Organic Cycle (ORC). The ORC is simulated using three organic working fluids, such as Toluene, Cyclohexane, and Acetone, meanwhile the solar system uses thermal oil Therminol 75. The present study shows the performance of this coupled system using historical solar annual radiation data ...
    • Engineering methods for enhancing railway geometry and winter road assessment: A safety and maintenance perspective 

      Brustad, Tanita Fossli (Doctoral thesis; Doktorgradsavhandling, 2020-06-22)
      In many areas around the world there are limited transportation possibilities when travelling between key cities. If these areas also experience demanding weather conditions or geography, getting from A to B, during difficult conditions, is usually not optimal in regards to accessibility, safety, and comfort. Under challenging conditions, two essential elements in strengthening accessibility, safety, ...
    • Engineering students' instrumental approaches to mathematics; some positive characteristics 

      Rensaa, Ragnhild Johanne (Journal article; Peer reviewed, 2018)
      The present paper presents three deliberately chosen mathematical episodes observed in a class of engineering students taking a basic calculus course. By drawing on analyses of instrumental and relational learning strategies, the episodes are shown to illustrate instrumental approaches indicated by the students. The paper discusses positive characteristics about these approaches while further data ...
    • Enhanced performance of microbial fuel cells using electrochemically treated carbon felt anode 

      Poureshghi, Fatemeh; Calay, Rajnish K; Das, Subhashis (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-10)
      The microbial fuel cell (MFC) technology is emerging as an effective technology for wastewater treatment to remove and detect many pollutants and simultaneously generate power. The anode is an essential component for bacterial attachment and extracellular electron transfer (EET). Thus, anode performance is critical for improving an MFC system's overall performance. Materials that are electronically ...
    • Enhancement of Vehicular Visible Light Communication Using Spherical Detector and Custom Lens Combinations 

      Yahia, Selma; Meraihi, Yassine; Amar, Ramdane-Cherif; Ho, Tu Dac; Eldeeb, Hossien (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-28)
      Vehicular Visible light communication (VLC) technology has recently attracted much interest from researchers and scientists. This technology enables connectivity between vehicles and infrastructures along the road by using vehicles’ headlights and taillights as wireless transmitters. The reliability of vehicle-to-vehicle (V2V) VLC systems is affected by several factors, such as car mobility, optics ...
    • Enhancing AI Systems through Representative Dataset, Transfer Learning, and Embedded Vision 

      Patil, Ravindra Rajaram (Doctoral thesis; Doktorgradsavhandling, 2024-02-28)
      <p>Artificial intelligence (AI) encompasses a range of techniques that enable machines to perceive, learn, and make intelligent decisions and it has emerged as transformative technology in many applications. This thesis presents the development of an AI model, focusing on the significance of the primary representative dataset and the effectiveness of transfer learning and fine-tuning techniques for ...
    • Enhancing the competitiveness of manufacturers through Small-scale Intelligent Manufacturing System (SIMS): A supply chain perspective 

      Yu, Hao; Solvang, Wei Deng (Conference object; Konferansebidrag, 2017-05-04)
      In order to survive in this competitive and ever changing market, manufacturers have to improve and enhance the competitiveness, flexibility, responsiveness and sustainability with the application of the cutting-edge technologies and innovative management methods. New concepts, i.e., Intelligent manufacturing, flexible manufacturing, agile manufacturing, network manufacturing, green manufacturing ...
    • Equivalent integral conditions related to bilinear Hardy-type inequalities 

      Kanjilal, Saikat; Persson, Lars Erik; Shambilova, Guldarya E (Journal article; Tidsskriftartikkel; Peer reviewed, 2019)
      Infinitely many, even scales of, equivalent conditions are derived to characterize the bilinear Hardy-type inequality under various ranges of parameters.
    • Estimating the Available Energy Flexibility A case study of Helgeland 

      Klæboe, Johanne Holst (Master thesis; Mastergradsoppgave, 2023-05-14)
      This thesis project was commissioned by Cegal and aimed to investigate the potential for demand-side flexibility in the Helgeland region, as well as evaluate forecasting methods for a demand-response system. The future energy situation in the area was analyzed, while the experimental part investigated forecasting methods which can be applied in a demand-response system. Finally, the project i ...
    • Estimating the impact of indoor relative humidity on SARS-CoV-2 airborne transmission risk using a new modification of the Wells-Riley model 

      Aganovic, Amar; Bi, Yang; Cao, Guangyu; Drangsholt, Finn; Kurnitski, Jarek; Wargocki, Pawel (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-08-23)
      A novel modified version of the Wells-Riley model was used to estimate the impact of relative humidity (RH) on the removal of respiratory droplets containing the SARS-CoV-2 virus by deposition through gravitational settling and its inactivation by biological decay; the effect of RH on susceptibility to SARS-CoV-2 was not considered. These effects were compared with the removal achieved by increased ...
    • Estimation of upward radiances and reflectances at the surface of the sea from above-surface measurements 

      Kleiv, Øyvind; Folkestad, Are; Høkedal, Jo; Aas, Eyvind; Sørensen, Kai (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-02)
      During 4 field days in the years 2009–2011, 22 data sets of measurements were collected in the inner Oslofjord, Norway. The data consist of recordings of spectral nadir radiances in air and water as well as spectral downward irradiance in air. The studied wavelengths are 351, 400, 413, 443, 490, 510, 560, 620, 665, 681, 709 and 754 nm. The water-leaving radiance and the reflected radiance at the ...
    • Evaluating of melting-ice process in a vertical pipe with consideration of net sensible heat 

      Nguyen, Hung Thanh; Gjerløw, Eirik; Huynh, Minh-Thu T. (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-04-19)
      In ice-melting process, motion of liquid–solid interface is complicated due to moving boundary, which is also called Stefan interface problem. Although the Stefan model has been widely utilized, it frequently overestimates the melting rate. In the present study, the net-sensible-heat of the phases are taken into account as an additional physical effect to the Stefan model for one-phase case and ...
    • Evaluating the cost competitiveness of metal additive manufacturing – A case study with metal material extrusion 

      Sæterbø, Mathias; Solvang, Wei Deng (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-25)
      Metal additive manufacturing (MAM) is a rapidly advancing manufacturing process with the potential to replace or supplement existing conventional manufacturing processes. MAM is currently associated with a high investment cost and is mostly seen in centralized manufacturing configurations with low-volume and high-value products. This paper evaluates the cost competitiveness of MAM by investigating ...
    • Evaluation of cascaded MPC performance in voltage source converters 

      Mokrushev, Ivan (Master thesis; Mastergradsoppgave, 2018-08-21)
      Model predictive control method becomes more popular in research over the last decade. Due to the growing popularity of the model predictive control concept, there are more and more questions about the effectiveness of this method in comparison with other methods. In this thesis cascaded model predictive control of grid connected voltage source converter with LCL filter has been evaluated. The ...
    • Evaluation of cyber security in agile manufacturing: Maturity of Technologies and Applications 

      Arnarson, Halldor; Safarpour, Faraz Kanafi; Kaarlela, Tero; Seldeslachts, Ulrich; Pieters, Roel (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-02-16)
      Utilizing Industry 4.0 technologies offers SMEs a possibility to increase productivity. Utilizing new technologies requires connectivity between production equipment, which raises Cyber Security (CS) issues that need to be addressed. In this work we analyse 18 demonstrators that are representative for different technologies and applications, and are of interest to the digitization of factories and ...
    • Evaluation of optimal replacement of natural aggregates by recycled concrete aggregates to achieve sufficient durability 

      Novakova, Iveta; Sjåfjell, Jørgen J.; Venkrbec, Vaclav (Preprint; Manuskript, 2022)
      The use of recycled concrete aggregate (RCA) is one way to reduce the depletion of raw materials for the production of concrete. In this article RCA was tested and evaluated. Concrete with 25 to 80 % of RCA was examined in terms of its durability performance, particularly capillary absorption and shrinkage. Capillary absorption testing showed that RCA has better or identical results as the reference ...
    • Evaluation of the impact of recycled concrete aggregates on the durability of concrete 

      Top, Liessa (Master thesis; Mastergradsoppgave, 2021-05-26)
      The building industry has one of the most significant contributions to global warming due to the production of building materials, transportation, building activities and demolition of structures. When the buildings and structures reach the end of their life-span, they are commonly demolished, and debrice is landfield or backfilled if it is evaluated as non-contaminated inert construction and ...
    • Evaluations of UAV-enabled FSO Communications in the Arctic 

      Pottoo, Sahil Nazir; Ellingsen, Pål Gunnar; Ho, Tu Dac (Journal article; Tidsskriftartikkel, 2022-02-16)
      This paper investigates the feasibility of using free space optics (FSO) for communication between multiple hovering unmanned aerial vehicles (UAVs) and a detection unit (DU) in the Arctic. The uniqueness that sets apart UAV-based FSO systems from conventional FSO systems is the dynamics of the system since location and inclination of the UAV changes over time due to wind load and UAV oscillations. ...
    • Evaluering Interface betingelsen, randkraver og samt frysning/melting front ved fasesendring material i hus-kompositt-veggen, basert på eksperiment temperatur data 

      Ji, Yiran (Master thesis; Mastergradsoppgave, 2023-05-14)
      Effektiv bruk energi i et hus/bygg er en drivende utvikling i byggenæring i de siste år. Det er en komplisert-omfang-og sammensatt problem for byggteknologi. For nevnt noe problemstiller, hvordan/hvilken energi kilde som elektrisk, fjernvarme, sol-, vind- som dekker huse behov og samt ha en gunstig effekt på natur, kostnad, og samfunnsforhold. Og, hvordan får vi optimal/gunstig fordeling energi i ...