Viser treff 352-371 av 919

    • Hill ascent confidence model and simulator for trailer trucks 

      Henriksen, Tanja Emilie (Master thesis; Mastergradsoppgave, 2022-05-13)
      This master thesis reports on the research of simulating hill ascensions on winter roads. By utilizing Python and Excel a simple prototype simulation was created. This simulation shows the velocity changes during the ascension, with different variables such as: initial velocity, gear, weight distribution, environment etc. The variables used are mostly based on real life measurements, with a ...
    • 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 ...
    • Homogenization of a singular random one-dimensional PDE with time-varying coefficients 

      Pardoux, Etienne; Piatnitski, Andrey (Journal article; Tidsskriftartikkel; Peer reviewed, 2012-05-04)
      In this paper we study the homogenization of a nonautonomous parabolic equation with a large random rapidly oscillating potential in the case of one-dimensional spatial variable. We show that if the potential is a statistically homogeneous rapidly oscillating function of both temporal and spatial variables, then, under proper mixing assumptions, the limit equation is deterministic, and convergence ...
    • Homogenization of biased convolution type operators 

      Piatnitski, Andrey; Zhizhina, Elena (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-11-07)
      This paper deals with homogenization of parabolic problems for integral convolution type operators with a non-symmetric jump kernel in a periodic elliptic medium. It is shown that the homogenization result holds in moving coordinates. We determine the corresponding effective velocity and prove that the limit operator is a second order parabolic operator with constant coefficients. We also consider ...
    • Homogenization of biomechanical models for plant tissues 

      Piatnitski, Andrey; Ptashnyk, Mariya (Journal article; Peer reviewed; Tidsskriftartikkel, 2017)
      In this paper homogenization of a mathematical model for plant tissue biomechanics is presented. The microscopic model constitutes a strongly coupled system of reaction-diffusion-convection equations for chemical processes in plant cells, the equations of poroelasticity for elastic deformations of plant cell walls and middle lamella, and Stokes equations for fluid flow inside the cells. The chemical ...
    • Homogenization of biomechanical models of plant tissues with randomly distributed cells 

      Piatnitski, Andrey; Ptashnyk, Mariya (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-15)
      In this paper homogenization of a mathematical model for biomechanics of a plant tissue with randomly distributed cells is considered. Mechanical properties of a plant tissue are modelled by a strongly coupled system of reaction-diffusion-convection equations for chemical processes in plant cells and cell walls, the equations of poroelasticity for elastic deformations of plant cell walls and middle ...
    • Homogenization of Ferromagnetic Energies on Poisson Random Sets in the Plane 

      Braides, Andrea; Piatnitski, Andrei (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-06)
      We prove that by scaling nearest-neighbour ferromagnetic energies de ned on Poisson random sets in the plane we obtain an isotropic perimeter energy with a surface tension characterised by an asymptotic formula. The result relies on proving that cells with `very long' or `very short' edges of the corresponding Voronoi tessellation can be neglected. In this way we may apply Geometry Measure ...
    • Homogenization of Levy-type operators with oscillating coefficients 

      Kassmann, Moritz; Piatnitski, Andrey; Zhizhina, Elena (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-01-05)
      The paper deals with homogenization of Lévy-type operators with rapidly oscillating coefficients. We consider cases of periodic and random statistically homogeneous micro-structures and show that in the limit we obtain a Lévy-operator. In the periodic case we study both symmetric and non-symmetric kernels whereas in the random case we only investigate symmetric kernels. We also address a nonlinear ...
    • Homogenization of Non-Autonomous Operators of Convolution Type in Periodic Media<sup>∗</sup> 

      Piatnitski, Andrei; Zhizhina, Elena (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-23)
      The paper deals with periodic homogenization problem for a para\-bo\-lic equation whose elliptic part is a convolution type operator with rapidly oscillating coefficients. It is assumed that the coefficients are rapidly oscillating periodic functions both in spatial and temporal variables and that the scaling is diffusive that is the scaling factor of the temporal variable is equal to the square of ...
    • Homogenization of nonisothermal immiscible incompressible two-phase flow in porous media 

      Amaziane, Brahim; Jurak, Murat; Pankratov, Leonid; Piatnitski, Andrey (Journal article; Peer reviewed, 2018-03-15)
      In this paper, we consider nonisothermal two-phase flows through heterogeneous porous media with periodic microstructure. Examples of such models appear in gas migration through engineered and geological barriers for a deep repository for radioactive waste, thermally enhanced oil recovery and geothermal systems. The mathematical model is given by a coupled system of two-phase flow equations, and an ...
    • Homogenization of random Navier–Stokes-type system for electrorheological fluid 

      Piatnitski, Andrey; Zhikov, Vasily (Peer reviewed; Journal article; Tidsskriftsartikkel, 2015-11-19)
      The paper deals with homogenization of Navier–Stokes-type system describing electrorheological fluid with random characteristics. Under non-standard growth conditions we construct the homogenized model and prove the convergence result. The structure of the limit equations is also studied.
    • Hospital Capacity Management & Optimization in Covid-19 

      Mahmood, Faizan (Master thesis; Mastergradsoppgave, 2022-05-15)
      A hospital is an institute in the healthcare system that provides us with services like patient treatment focusing on specialized medical staff, including doctors, nurses and other healthcare workers, medical equipment, and procedures. The hospital is the first line of defence against any type of illness or a pandemic; it is the sector that has been the most devastated and is the most vulnerable. ...
    • (Hp− Lp -Type inequalities for subsequences of Nörlund means of Walsh–Fourier series 

      Baramidze, David; Persson, Lars-Erik; Tangrand, Kristoffer Meyer; Tephnadze, George (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-04-07)
    • Human-Robot Collaboration: Task Sharing Through Virtual Reality 

      Shu, Beibei; Sziebig, Gabor; Pieskä, Sakari (Peer reviewed; Book; Chapter, 2018-12-31)
      Collaborative Robots provide many possibilities, when it comes to Human-Robot Collaboration. Until now, these approaches are usually custom made, sensor-integrated solutions, where the robot's safety controller ensures the safety of the human worker. These solutions are according to today's rules and standards. We propose to extend these solutions with including Virtual Realty as a sensor and to ...
    • 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.
    • Hvordan kan bruk av digitale verktøyer effektivisere produksjon på byggeplass for en mellomstor bedrift? Digitalisering i Sortland Entreprenør 

      Pettersen, Kaja (Master thesis; Mastergradsoppgave, 2018-08-16)
      Verden befinner seg i dag i en rask og omveltende teknologisk utvikling, der alle næringer blir påvirket av digitalisering som radikalt endrer måten å jobbe, samhandle og kommunisere på. Over lengre tid har byggebransjen vært en bransje der innovasjon og nytenkning ikke har vært et satsningsområde. Synkende effektivitet og økt konkurranse mellom aktører har medført at en endring av arbeidsmetode er ...
    • Hvordan kommuniserer lærere med elevene i teknologiprosjekter? 

      Lysne, Dag Atle; Esjeholm, Bjørn Tore (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-09-14)
      Inquiry-based methods have been seen as important for developing science in school. There are good reasons why the work of designing various technological devices in technology should also be part of inquiry-based methods. If so, it requires that the teachers have an exploratory approach in communicat-ing with students. In this paper, we analyze the communication between teachers and students in six ...
    • Hvordan vi motiverer våre internasjonale ingeniørstudenter 

      Takamine, Kaori; Eilertsen, Randi; Dybdahl, Tone Harr; Holbø, Marianne (Conference object; Konferansebidrag, 2023)
    • A Hybrid Biomass Hydrothermal Gasification- Solid Oxide Fuel Cell System Combined with Improved CHP Plant for Sustainable Power Generation 

      Mustafa, Mahmoud; Nord, Natasa; Calay, Rajnish K; Mustafa, Mohamad (Journal article; Peer reviewed; Tidsskriftartikkel, 2017)
      The most popular technique, so far, for biomass waste to energy conversion has been incineration, but this technique has raised a lot of objection among nature activists due to the release of particulate matter and pollutants like nitrogen oxides (NOx) into the atmosphere. However, advanced non-incineration conversion methods like pyrolysis, thermal gasification, and plasma-arc gasification are ...