Now showing items 1-8 of 8

    • Exploring benefits of using blending splines as transition curves 

      Brustad, Tanita Fossli; Dalmo, Rune (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-19)
      Track geometry is a fundamental subject in railway construction. With the demand for increased capacity in terms of load and speed, the need for suitable transitions between consecutive track sections is highly relevant. Properly constructed transition curves lead to improved travel comfort, increased safety, and reduced wear. The well known clothoid curve is widely used as a transition curve; ...
    • Exploring future C++ features within a geometric modeling context 

      Bratlie, Jostein; Dalmo, Rune (Peer reviewed; Conference object; Chapter, 2019-11)
      The development of the C++ programming language and its standard library has undergone a renaissance since the introduction of the C++11 standard, making the language more relevant than ever, through modern features, simplification and expansion of the standard library. Comparing past and future feature sets (C++17, C++20, ...) similar to comparing different programming languages. In this article ...
    • Finite element application of ERBS extraction 

      Kravetc, Tatiana; Dalmo, Rune (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-24)
      In this paper we explore ERBS extraction in application to a heat conduction problem.Two types of basis functions are considered: B-spline and expo-rational B-spline (ERBS)combined with Bernstein polynomials. The first one is a global basis defined on a subdomain whose size is related to the spline degree, while the second one is a strictlylocal basis under the local geometry. While all the coefficients ...
    • Local refinement of ERBS curves 

      Dalmo, Rune (Journal article; Peer reviewed; Chapter, 2013-12-31)
      Expo-rational B-splines (ERBS) provide a blending type construction where local functions at each knot are blended together by infinitely smooth basis functions. In this work we consider some specific ERBS curves that are approximations of parametric curves. We study local refinement to increase flexibility by inserting local control curves at points of interest on the ERBS curve. Inserting knots ...
    • Matrix factorization of multivariate Bernstein polynomials 

      Dalmo, Rune (Journal article; Tidsskriftartikkel; Peer reviewed, 2015)
      Ordinary univariate Bernstein polynomials can be represented in matrix form using factor matrices. In this paper we present the definition and basic properties of such factor matrices extended from the univariate case to the general case of arbitrary number of variables by using barycentric coordinates in the hyper-simplices of respective dimension. The main results in the paper are related to the ...
    • Multi-source data collection for state-of-the-art data analysis from ground-proximate images in sea ice classification 

      Woltmann, Lucas; Dalmo, Rune; Kristiansen, Raymond (Peer reviewed; Konferansebidrag; Bok; Conference object; Book, 2017-08-08)
      In modern data analysis it is imperative to use well maintained data sources with curated content. This publication gives an approach for research areas, where there is no such central facility. The specific area used here is sea ice classification from images. The publication is split into two parts. The first part describes the integration of discontinuous sources for different aspects of data ...
    • Railway transition curves: A review of the state-of-the-art and future research 

      Brustad, Tanita Fossli; Dalmo, Rune (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-18)
      Transition curves are a useful tool for lateral alignment of railway segments. Their design is important to ensure safe and comfortable travel for passengers and cargo. Well designed transition curves can lead to reduced wear of tracks and vehicles, which is beneficial from a maintenance point of view. Extensive studies have been performed through decades to find transition curves that can replace ...
    • Regression analysis using a blending type spline construction 

      Kravetc, Tatiana; Bang, Børre; Dalmo, Rune (Peer reviewed; Chapter; Bokkapittel, 2017-10-18)
      Regression analysis allows us to track the dynamics of change in measured data and to investigate their properties. A sufficiently good model allows us to predict the behavior of dependent variables with higher accuracy, and to propose a more precise data generation hypothesis. By using polynomial approximation for big data sets with complex dependencies we get piecewise smooth functions. One way ...