Viser treff 81-100 av 242

    • A Feedforward Neural Network for Modeling of Average Pressure Frequency Response 

      Pettersson, Klas; Karzhou, Andrei; Pettersson, Irina (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-02-22)
      The Helmholtz equation has been used for modeling the sound pressure field under a harmonic load. Computing harmonic sound pressure fields by means of solving Helmholtz equation can quickly become unfeasible if one wants to study many different geometries for ranges of frequencies. We propose a machine learning approach, namely a feedforward dense neural network, for computing the average sound ...
    • Synaptus: A Matlab/Octave toolbox for synthetic aperture ultrasound imaging. 

      Skjelvareid, Martin (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-08-08)
      Underlying patterns and factors behind suicides of patients in treatment are still unclear and there is a pressing need for more studies to address this knowledge gap. We analysed 278 cases of suicide reported to The Norwegian System of Patient Injury Compensation, drawing on anonymised data, i.e., age group, gender, diagnostic category, type of treatment provided, inpatient vs. outpatient status, ...
    • Continuous refinements of some Jensen-type inequalities via strong convexity with applications 

      Nikolova, Ludmila; Persson, Lars-Erik; Varošanec, Sanja (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-05-23)
      In this paper we prove new continuous refinements of some Jensen type inequalities in both direct and reversed forms. As applications we also derive some continuous refinements of Hermite–Hadamard, Hölder, and Popoviciu type inequalities. As particular cases we point out the corresponding results for sums and integrals showing that our results contain both several well-known but also some new ...
    • Weighted Hardy Operators in Complementary Morrey Spaces 

      Lukkassen, Dag; Persson, Lars-Erik; Samko, Stefan (Journal article; Tidsskriftartikkel; Peer reviewed, 2012-11-11)
      We study the weighted -boundedness of the multidimensional weighted Hardy-type operators and with radial type weight , in the generalized complementary Morrey spaces defined by an almost increasing function . We prove a theorem which provides conditions, in terms of some integral inequalities imposed on and , for such a boundedness. These conditions are sufficient in the general case, but we ...
    • Some new iterated Hardy-type inequalities: the case theta=1 

      Gogatishvili, Amiran; Mustafayev, Rza; Persson, Lars Erik (Journal article; Tidsskriftartikkel; Peer reviewed, 2013-11-08)
      In this paper we characterize the validity of the Hardy-type inequality &#8741 &#8741 &#8747 <sub>s</sub>&#8734) h(z)dz &#8741 p,u,(0,t) &#8741 q,w,(=,&#8734≤ c&#8741h&#8741 1,v(0,&#8734) where 0 < p < ∞,0< q ≤ +∞, u, w and v are weight functions on (0,∞). It is pointed out that this characterization can be used to obtain new characterizations for the boundedness between weighted Lebesgue spaces ...
    • 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 ...
    • Isogeometric analysis using a tensor product blending spline construction 

      Kravetc, Tatiana (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-06-01)
      In this paper, we introduce a blending spline type construction into the isogeometric analysis. We consider a general algorithm for solving a number of boundary value problems, including heat equation, wave equation, linear elasticity, etc. The usage of blending spline construction in the isogeometric context mixes standard finite element and NURBS-based approaches while accumulating the benefits ...
    • Experiments on turbulence from colliding ice floes 

      Løken, Trygve Kvåle; Marchenko, Aleksey; Ellevold, Thea Josefine; Rabault, Jean; Jensen, Atle (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-06-16)
      Increased knowledge about energy dissipation processes around colliding ice floes is important for improved understanding of atmosphere-ice-ocean energy transfer, wave propagation through sea ice, and the polar climates. The aim of this study is to obtain such information by investigating colliding ice floe dynamics in a large-scale experiment and directly measuring and quantifying the turbulent ...
    • Analysis of local climate effects for Martineåsen development project in Larvik 

      Shunina, Maria (Master thesis; Mastergradsoppgave, 2017-08-15)
      The goal of this thesis is to perform analysis of local climate effects for Martineåsen development project in Larvik. The Norwegian regulatory acts place a strict requirements on outdoor areas comfort criteria and thus for the purpose of said development project, strict adherence to these acts is necessary. The outdoor comfort in cold climate is mostly governed by wind, and thus study of local ...
    • Weighted Boundedness of Certain Sublinear Operators in Generalized Morrey Spaces on Quasi-Metric Measure Spaces Under the Growth Condition 

      Samko, Natasha Gabatsuyevna (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-03-17)
      We prove weighted boundedness of Calderón–Zygmund and maximal singular operators in generalized Morrey spaces on quasi-metric measure spaces, in general non-homogeneous, only under the growth condition on the measure, for a certain class of weights. Weights and characteristic of the spaces are independent of each other. Weighted boundedness of the maximal operator is also proved in the case when ...
    • Spatial Mapping Using HoloLens 2. A Proposal for Improvement and an Analysis of Inner Workings 

      Levoll-Steen, Casper André (Master thesis; Mastergradsoppgave, 2022-05-16)
      In this thesis we focus on improving the spatial mapping of Microsoft's augmented reality glasses HoloLens 2. Firstly, an in depth analysis of inner workings and limitations, based on public resources, is conducted. This is then followed by a series of experiments in a small and simple indoor environment, the experiments are designed to extract additional information about the mapping which could ...
    • 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 ...
    • Automatic Generation of Custom Image Recognition Models 

      Hanssen, Magnus Fredheim (Master thesis; Mastergradsoppgave, 2022-05-15)
      In this thesis, we examine the viability of training a convolutional neural network using synthetic data. The cnn is used for image recognition in an rms. We create a program that can render 3D models from STL files as images with varied backgrounds. The process of creating and training an image recognition model is also automated. Lastly, the model is used for image recognition. The report ...
    • Deployment of a Neo-Hookean membrane: experimental and numerical analysis 

      Moatamedi, Mojtaba; Al-Bahkali, Essam; Erchiqui, Fouad; Souli, M (Journal article; Tidsskriftartikkel; Peer reviewed, 2013-03-31)
      The aim of this research is to assess the response of a thin membrane subjected to high-pressure gas loading for inflation. This procedure is applied during the design process of the membrane structure to allow the product to resist high-pressure loading and to further characterize the hyper-elastic material. The simulation in this work considers the standard procedures used in the LS-DYNA software, ...
    • Fluid-structure Interaction for Water Hammers Effects in Petroleum and Nuclear Plants 

      Messahel, Ramzi; Cohen, B; Souli, M; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2011-12-31)
      Fluid-Structure Interaction (FSI) becomes more and more the focus of computational engineering in Petroleum and Nuclear Industry in the last years. These problems are computer time consuming and require new stable and accurate coupling algorithms to be solved. For the last decades, the new development of coupling algorithms, and the increasing of computer performance have allowed to solve some ...
    • Numerical investigation of vibration and dynamic pressure of a vertical axis wind turbine 

      Erchiqui, Fouad; Souli, M; Moatamedi, Mojtaba; Albahkali, E (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-12-31)
      In the environmental field, the problems of vibration reduction have become a major preoccupation, particularly on the noise generated by the acoustic radiation pressure produced by wind turbines. This paper is aimed at presenting the investigation on the application of FEM element method for study the acoustic radiation pressure produced by vertical-axis wind turbine. For this initiative, we ...
    • Exploring auction based energy trade with the support of MAS and blockchain technology 

      Shvetsov, Nikita (Master thesis; Mastergradsoppgave, 2017-06-13)
      This document describes a simulation of the local energy market with support of multi-agent approach and blockchain technology. The investigated points include blockchain technology and its applications, Ethereum platform and smart contracts as a tool for storing data of operations and creating assets, multi-agent approach to model the local energy market. The document explores building a solution ...
    • Development of concepts for lifeboat evacuation in arctic regions. Dry evacuation from lifeboat to land or sea ice 

      Hansen, Marius Didriksen; Olawoyin, Bashir Olatunde (Master thesis; Mastergradsoppgave, 2021-05-18)
      The evacuation of passengers from a ship in distress is an essential measure in marine safety. Safety is only guaranteed when the passengers are evacuated to shore, especially in remote areas like the arctic region. There has been growing awareness with lack of knowledge, standards, routine, and documentation regarding marine search and rescue in the arctic region in recent years. This has been the ...
    • Frame and casing design of second life battery energy storage systems 

      Kurup, Anirudh (Master thesis; Mastergradsoppgave, 2021-05-20)
      The design of the frame and casing for two types of battery storage systems was carried out through a product development process on behalf of RePack AS. The primary design objectives were clarified using an objective tree method. The main functions of the designs were explored, and the product requirements were compiled stating the various demands and wishes pertaining to the products. Design ...
    • On a New Class of Hardy-type Inequalities 

      Adeleke, EO; Cizmesija, Aleksandra; Oguntuase, JA; Persson, Lars Erik; Pokaz, D (Journal article; Tidsskriftartikkel; Peer reviewed, 2012-11-05)
      In this paper, we generalize a Hardy-type inequality to the class of arbitrary non-negative functions bounded from below and above with a convex function multiplied with positive real constants. This enables us to obtain new generalizations of the classical integral Hardy, Hardy-Hilbert, Hardy-Littlewood-Pólya, and Pólya-Knopp inequalities as well as of Godunova’s and of some recently obtained ...