• Estimating tail-beat frequency using split-beam echosounders

    Nils Olav Handegard; ; Ole Brix

    Data from a standard split-beam echosounder are used to estimate tail-beat frequency within a dense herring (Clupea harengus L.) layer. The data were collected by lowering a horizontally projecting 38 kHz split-beam transducer into a herring layer at 245-m depth. Individual targets were concatenated into tracks, and a fast Fourier transform was used to estimate the periodogram of the backscattering strengths along each track.

  • The Seismic Analyzer: Interpreting and Illustrating 2D Seismic Data

    ; ; John Thurmond, John Gjelberg, and M. Eduard Gröller

    Abstract —We present a toolbox for quickly interpreting and illustrating 2D slices of seismic volumetric reflection data. Searching for oil and gas involves creating a structural overview of seismic reflection data to identify hydrocarbon reservoirs. We improve the search of seismic structures by precalculating the horizon structures of the seismic data prior to interpretation. We improve the annotation of seismic structures by applying novel illustrative rendering algorithms tailored to seismic data, such as deformed texturing and line and texture transfer functions. The illustrative rendering results in multi-attribute and scale invariant visualizations where features are represented clearly in both highly zoomed in and zoomed out views. Thumbnail views in combination with interactive appearance control allows for a quick overview of the data before detailed interpretation takes place. These techniques help reduce the work of seismic illustrators and interpreters.

  • Illustrated Ultrasound for Multimodal Data Interpretation of Liver Examinations

    Ivan Viola; ; Kim Nylund, Ola Kristoffer Øye

    Traditional visualization of real-time 2D ultrasound data is difficult to interpret, even for experienced medical personnel. To make the interpretation during the education phase easier, we enhance the visualization during liver examinations with an abstracted depiction of relevant anatomical structures, here denoted as illustrated ultrasound. The specifics of enhancing structures are available through an interactively co-registered computed tomography, which has been enhanced by semantic information. To assist the orientation in the liver, we partition the liver into Couinaud segments. They are defined in a rapid segmentation process based on linked 2D slice views and 3D exploded views. The semantics are interactively related from the co-registered modality to the real-time ultrasound via co-registration. During the illustrated ultrasound examination training we provide visual enhancements that depict which liver segments are intersected by the ultrasound slice.

  • Flow imaging by high speed transmission tomography.

    G A Johansen; U Hampel; B T Hjertaker

    Radiation transmission tomography has found widespread use in cross sectional imaging of industrial processes, particularly for research purposes. Many laboratories have built their own 3rd generation mechanical scanners based on one fan beam collimated source and several detectors in an arc shaped array. Such systems are sufficient for imaging of slow processes or where temporal averaging of the process dynamics is acceptable. Applications where the process dynamics is to be investigated is more demanding.

  • Geiger Müller detectors for gamma-ray tomography

    Geir Anton Johansen; ; Oddbjørn Vagle; Øystein Olsen; Ilker Meric

    Recent developments within Geiger Müller tube technology (GMT) make these detectors potential candidates for application in gamma-ray tomography (GRT) systems. GMTs are not energy sensitive, but are still applicable for pulse counting in GRT. GMTs have the advantage of being very rugged and requiring simple read-out electronics only.

  • A novel approach to acoustic liquid density measurements using a buffer rod based measuring cell.

    ; ; Bjorndal, E.

    A new method for measuring the pressure reflection coefficient in a buffer rod configuration is presented, together with experimental results for acoustic measurements of the liquid density, based on the measurement of the liquid's acoustic impedance.

  • Acoustic methods for obtaining the pressure reflection coefficient from a buffer rod based measurement cell.

    Bjorndal, E. ; ;

    The known acoustic methods for obtaining the pressure reflection coefficient from a buffer rod based measurement cell are presented, along with 2 new generic approaches for measuring the pressure reflection coefficient using 2 buffer rods enclosing the liquid to be characterized in a symmetrical arrangement.

  • Installation Effects on the Easington Ultrasonic Fiscal Metering Station

    ; ; Paulsen, A.

  • Haemoglobin polymorphisms affect the oxygen- binding properties in Atlantic cod populations

    Ole Brix; Ø. Andersen, O.F. Wetten, C.N. De Rosa, C. Andre, C.c. Alinovi, M. Colafranceschi, A. Colosimo

    A major challenge in evolutionary biology is to identify the genes underlying adaptation. The oxygentransporting haemoglobins directly link external conditions with metabolic needs and therefore represent a unique system for studying environmental effects on molecular evolution.

  • Ultrasonic signal transmission in plates – Study of a steel plate immersed in water

    ; ; Magne Vestrheim

    In the present work, a theory for the description of the propagation of plane ultrasonic waves through a fluid loaded plate is described. The theory assumes different fluid loading at the two interfaces, but the special case with the same fluid loading is also treated.

  • A field laboratory for monitoring CO2 leakage

    ; Dillen, M.; Lindeberg; E.; Aagaard, P.; Aker, E.; Sther, O.M.; Johansen, H.; Lien, M.; Hatzignatiou, D.G.; Golmen, L.

    The long-term safety of future CO2 storage projects in aquifers will not only rely on a comprehensive geological characterisation of the formation and capillary seal, but also on the ability to effectively monitor the underground migration of CO2 to allow immediate and effective remediation to prevent CO2 from escaping to the atmosphere in case of leakage.

  • Two-Level Approach to Efficient Visualization of Protein Dynamics

    ; Ivan Viola Member, IEEE Computer Society , Nathalie Reuter and Helwig Hauser Member, IEEE

    Proteins are highly flexible and large amplitude deformations of their structure, also called slow dynamics, are often decisive to their function. We present a two-level rendering approach that enables visualization of slow dynamics of large protein assemblies.

  • Illustrative Rendering of Seismic Data

    ; ; John Thurmond and Meister Eduard Gröller

    In our work we present techniques for illustrative rendering of interpreted seismic volume data by adopting elements from geology book illustra tions. We also introduce combined visualization techniques of interpreted and uninterpreted data for validation, comparison and interdisciplinary communication reasons.

  • A Virtual Reality Solution for Evaluation of Radiotherapy Plans

    Ludvig Paul Muren; ; ; ; Anfinn Mehus, Yngve Kvinnsland

    This report presents a VR system for evaluation of treatment plans used in radiotherapy (RT), developed to improve the understanding of the spatial relationships between the patient anatomy and the calculated dose distribution.

  • A Decade of Increased Oil Recovery in Virtual Reality

    ; ; Endre M. Lidal, Jens Grimsgaard, Rolf Helland

  • Processing 4-D acoustic data from the worlds most advanced multi-beam fisheries sonar

    Korneliussen, R. J; ;

    Acoustic methods are widely used for estimating fish abundance. Institute of Marine Research (IMR) uses data from echo sounder to calculate abundance of many fish species. Vertical echo sounders does not cover the region close to the sea-surface, and is therefore not suited to investigations at those times the fish swim close to the surface.

  • Uncertainty analysis of emissions from the Statoil Mongstad oil refinery

    Anne Lise Hopland Vågenes; ; Bernhard Sørli and Helge Jørgenvik

    In new European and national legislations, there is increased focus on the reporting of the emmissions related to greenhouse gases from process plants. This includes reporting and documentation of uncertainty in the reported emmissions, in addition to specific uncertainty limits depending on the type of emission and type of measurement regime.

  • The large scale survey system - LSSS

    Korneliussen, R.J.; ; ; ; ; ; Ona, E., Patel, R., Godø, O.R., Giertsen, C., , Knudsen, H. P., Lien, G.

    Acoustic methods are widely used for estimating fish abundance. Currently the Institute of Marine Research (IMR) uses the Bergen Echo Integrator (BEI) to analyse the acoustic data. Development of BEI started in 1987, and although it still fills its purpose it has become increasingly difficult to maintain and expand.

  • FAVEum Framework Architecture for Virtual Environments applied to Urban Modelling

    J. O. Erdal; ; ; ;

    FAVE (Framework Architecture for Virtual Environments) is a generic software frame work for developing VR applications. It contains a toolkit of us er interface widgets, navigation techniques, interaction features and optimised visualisation algorithms.

  • FAVE, Framework Architecture for Virtual Environments, Use case; visualization of online CFD simulations

    ; ; ;

    We present a highly configurable framework for virtual environments. The framework consists of a toolbox of classes which are instantiated into objects as dictated by our own XML specification language. The result is that application behavior is specified with XML atruntime instead of in source code at compile time.

  • FAVE, A Framework Architecture for Virtual Environments

    ; ; ;

    We present a highly config urable, rapid prototyping framework for immersive virtual environments. The framework is object oriented, event driven and has been designed with collaboration over networks in mind. It consists of several abstraction layers and can be used as a black box framework.

  • Fast nummeric scheme related to curvature minimization: a brief and elementary review


    We will treat variational models that use Euler’s elastica and related higher order derivatives as regularizers. These models normally lead to higher order partial differential equations with complicated nonlinearities. It is difficult to solve these equations numerically.

  • Gel2DE - A software tool for correlation analysis of 2D gel electrophoresis data

    Ola Kristoffer Øye (CMR); ; Katarina M Jørgensen, Department of Clinical Science, Hematology Section, University of Bergen, Bergen, Norway; Sigrun M Hjelle, Department of Clinical Science, Hematology Section, University of Bergen, Bergen, Norway; André Sulen, Department of Clinical Science, Hematology Section, University of Bergen, Bergen, Norway; Bjørn Tore Gjertsen, Department of Clinical Science, Hematology Section, University of Bergen, Bergen, Norway, Department of Internal Medicine, Hematology Section, Haukeland University Hospital, Bergen, Norway

    Pixel-by-pixel correlation of aligned 2D images permits analysis of complex protein patterns. We anticipate that the Gel2DE correlation software will be a useful tool for future bioinformatics discoveries through 2D gel electrophoresis.

  • Geological Storytelling – Graphically Exploring and Communicating Geological Sketches

    Endre M. Lidal; Helwig Hauser and Ivan Viola

    Developing structural geological models from exploratory subsea imaging is difficult and an ill-posed process. Therefore, in practice several experts generate a larger number of geological interpretations. This leads to the situation that a number of geological sketches are prepared and examined for the next steps in the oil and gas exploration pipeline.

  • Uncertainty analysis of multiphase flow meters used for allocation measurements: Field experiences and future challenges

    ; ; Soldal, EL; Åbro, E

    Uncertainty analysis of multiphase flow meters used for allocation measurements: Field experiences and future challenges.

  • HANDBOOK OF UNCERTAINTY CALCULATIONS - Fiscal Orifice Gas and Turbine Oil Metering Stations

    Eivind Olav Dahl; ; ;

    Norwegian regulations relating to measurement of petroleum for fiscal purposes and for calculation of CO2 tax require that the overall measurement uncertainty be documented to be within defined limits. However, the different methods used gave different results. A consistent, standardised method of uncertainty estimation was required, so that different measurement systems could be directly compared.

  • HANDBOOK OF UNCERTAINTY CALCULATIONS - Ultrasonic fiscal gas metering stations

    ; ;

    Norwegian regulations relating to fiscal measurement of oil and gas require that the overall measurement uncertainty is documented to be within defined limits. However, the different methods used have given different results. A consistent and standardised method of uncertainty evaluation has been required, so that different measurement systems could be directly and reliably compared.

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