• Permittivity measurements using dual open ended coaxial probes

    Karimi, Mahsa

    The motivation for this study has been to conduct a feasibility study on a measuring device to monitor hydrate formation close to the inner surface of a pipe where a multiphase hydrocarbon fluid mixture is flowing. This measurement device is supposed to measure both the permittivity and the conductivity of the fluid mixture, and estimate the hydrate layer thickness formed on the inner surface of the pipe.

  • Optimizing performance of equipment for thermostimulation of muscle tissue using COMSOL Multiphysics

    Kocbach, Jan; Folgerø, Kjetil; Louise Mohn, Ole Brix

    A multiphysics simulation approach is used in order to analyse and optimize performance of thermostimulation equipment. The temperature distribution and electric field distribution within the body tissue is simulated for varying body composition, for varying design parameters of the thermostimulation equipment and for different heating methods.

  • Monitoring oil–water mixture separation by time domain reflectometry

    E M Bruvik; Folgerø, Kjetil; B T Hjertaker; S K Meyer

    Effective separation of water and oil is an essential part of petroleum production. Time domain reflectometry (TDR) can be used to profile the separation of hydrocarbon oil–water mixtures. In such two-component systems, metal electrodes will become oil-coated due to their affinity to oil.

  • On the treatment of ill-conditioned cases in the Monte Carlo library least-squares approach for inverse radiation analyzers

    Ilker Meric; Holstad, Marie Bueie; Geir A Johansen; John Mattingly; Robin P Gardner

    Prompt gamma-ray neutron activation analysis (PGNAA) has been and still is one of the major methods of choice for the elemental analysis of various bulk samples. This is mostly due to the fact that PGNAA offers a rapid, non-destructive and on-line means of sample interrogation.

  • Enhancement of the intrinsic gamma-ray stopping efficiency of Geiger–Müller counters

    Ilker Meric; Holstad, Marie Bueie; Geir Anton Johansen, Adan F. Calderon, Robin P. Gardner

    Geiger–Müller counters are frequently employed in many industrial radiation gauges. However, it is of practical interest to further extend the usage areas of these detectors to include applications such as dual modality densitometry and industrial gamma-ray tomography. This is mainly because these counters exhibit a high degree of robustness in demanding environments, their relatively low cost and the fact that they require simple read-out electronics.

  • Effect of wave motion on wind lidar measurements - comparison testing with controlled motion applied.

    Hellevang, Jon Oddvar;

    We will presented the key results from a comparison test between a pulsed and continuous wave (CW) lidar systems subject to controlled wave motion.

  • Multivariate Analysis of Crude Oil Composition and Fluid Properties Used in Multiphase Flow Metering (MFM)

    Andreas L. Tomren; Folgerø, Kjetil; Tanja Barth

    Crude oil characterization by infrared (IR) spectroscopy and whole oil gas chromatography (GC) has been used to provide data for establishing multivariate prediction models for physical properties of crude oils.

  • Water-based tape-casting of SOFC composite 3YSZ/8YSZ electrolytes and ionic conductivity of their pellets

    Ilea, Crina Silvia; Wærnhus, Ivar; Hanna Tikkanena; Firuta Gogac; Eugen Doroltid

    Electrolyte supports for SOFC applications were obtained by water-based tape-casting. Slurries of commercial 3YSZ and 8YSZ and mixtures with a mass ratio of 25/75 and 75/25, respectively, were prepared. A commercial acrylic polymer binder with dispersive properties was used. The drying conditions for obtaining crack-free green tapes were studied.

  • Oppdatert usikkerhetshåndbok for fiskale gassmålestasjoner

    Frøysa, Kjell-Eivind; Lied, Gaute Øverås; Dag Flølo, Statoil

    Oppdatert usikkerhetshåndbok for fiskale gassmålestasjoner

  • Illustrative Couinaud Segmentation for Ultrasound Liver Ex-aminations

    Ola Kristoffer Øye (CMR); Ulvang, Dag Magne; Odd Helge Gilja (HUS/UiB), Helwig Hauser (UiB), Ivan Viola (UiB),

    Couinaud segmentation is a widely used liver partitioning scheme for describing the spatial relation between diagnostically relevant anatomical and pathological features in the liver. In this paper, we propose a new methodology for effectively conveying these spatial relations during the ultrasound examinations.

  • Curve Density Estimates

    Lampe, Ove Daae; Helwig Hauser

    In this work, we present a technique based on kernel density estimation for rendering smooth curves. With this approach, we produce uncluttered and expressive pictures, revealing frequency information about one, or, multiple curves, independent of the level of detail in the data, the zoom level, and the screen resolution.

  • Model Building in Visualization Space

    Lampe, Ove Daae; Helwig Hauser

    Researching formal models that explain selected natural phenomena of interest is a central aspect of most scientific work. A tested and confirmed model can be the key to classification, knowledge crystallization, and prediction.With this paper we propose a new approach to rapidly draft, fit and quantify model prototypes in visualization space.

  • BAKTRAK: Backtracking drifting objects using an iterative algorithm with a forward trajectory model

    Øyvind Breivik; Bekkvik, Tor Christian; Atle Ommundsen, Cecilie Wettre

    The task of determining the origin of a drifting object after it has been located is highly complex due to the uncertainties in drift properties and environmental forcing (wind, waves and surface currents). Usually the origin is inferred by running a trajectory model (stochastic or deterministic) in reverse. However, this approach has some severe drawbacks, most notably the fact that many drifting objects go through nonlinear state changes underway (e.g., evaporating oil or a capsizing lifeboat).

  • Chromatic Shadows for Improved Perception

    Solteszova, Veronika; Patel, Daniel; Ivan Viola

    Soft shadows are effective depth and shape cues. However, traditional shadowing algorithms decrease the luminance in shadow areas. The features in shadow become dark and thus shadowing causes information hiding. For this reason, in shadowed areas, medical illustrators decrease the luminance less and compensate the lower luminance range by adding color, i.e., by introducing a chromatic component.

  • Interactive Visualization of Streaming Data with Kernel Density Estimation

    Lampe, Ove Daae; Helwig Hauser

    In this paper, we discuss the extension and integration of the statistical concept of Kernel Density Estimation (KDE) in a scatterplot-like visualization for dynamic data at interactive rates. We present a line kernel for representing streaming data, we discuss how the concept of KDE can be adapted to enable a continuous representation of the distribution of a dependent variable of a 2D domain.

  • PhD Education Through Apprenticeship

    Patel, Daniel; Stefan Bruckner, Meister Eduard Gröller

    We describe and analyze the PhD education in the visualization group at the Vienna University of Technology and set the education in a larger perspective. Four central mechanisms drive the PhD education in Vienna.

  • Enhancing Visualization with Real-Time Frequency-based Transfer Functions

    Erald Vuçini; Patel, Daniel; Meister Eduard Gröller

    Transfer functions have a crucial role in the understanding and visualization of 3D data. While research has scrutinized the possible uses of one and multi-dimensional transfer functions in the spatial domain, to our knowledge, no attempt has been done to explore transfer functions in the frequency domain. In this work we propose transfer functions for the purpose of frequency analysis and visualization of 3D data.

  • Untangling the intracellular signalling network in cancer -- A strategy for data integration in acute myeloid leukaemia

    Katarina M. Jørgensen; Sigrun M. Hjelle, Ola K. Øye, Pål Puntervoll, Håkon Reikvam, Jørn Skavland, Endre Anderssen, Øystein Bruserud and Bjørn Tore Gjertsen

    Protein and gene networks centred on the regulatory tumour suppressor proteins may be of crucial importance both in carcinogenesis and in the response to chemotherapy. Tumour suppressor protein p53 integrates intracellular data in stress responses, receiving signals and translating these into differential gene expression.

  • Petroleum technology supports fisheries management

    Ole Brix; A.O. Pedersen, J. Spilde, J. Lied, E. O. Dahl

    No adequate technology has to our knowledge so far been developed for reliable online monitoring of harvested fish quantities. We demonstrate in this study that multiphase measurement technology successfully applied in the petroleum industry for measurements of pipeline flow of oil and gases (Nilsson, 1989; Stalheim, 1991; Halvorsen, 1992) also can be used for objective recording of withdrawals from the sea (Spilde, 2001).

  • Produced water characterization by prompt gamma-ray neutron activation analysis

    Ilker Meric; Holstad, Marie Bueie; Geir A Johansen; Jiaxin Wang; Robin P Gardner

    Multiphase gas/oil/water measurement has been and still is a challenging task within the petroleum industry. The requirements of measurement efficiency and accuracy have been continuously increasing at the same time as the trend is to use subsea installations. As a response, the design of the SOFA (Subsea Online Fluid Analyser) concept was initiated by Christian Michelsen Research in cooperation with the University of Bergen. The final design of the analyser is yet to be completed.

  • A revised target strength–length estimate for blue whiting (Micromesistius poutassou): implications for biomass estimates

    Pedersen, Geir; Olav Rune Godø; Egil Ona; Gavin J. Macaulay

    Acoustic abundance estimates of blue whiting have generally been higher than estimates based on catch data. One explanation has been that the relationship between acoustic target strength (TS) and length is too low and hence overestimates the number of fish.

  • A revised length to TS estimate for blue whiting (Micromesistius poutassou) and implications for biomass estimates

    Pedersen, Geir; Gavin Macaulay; Gavin Macaulay; Olav R. Godø; Egil Ona

  • High-Temperature Electrochemical Characterization of Ru Core Pt Shell Fuel Cell Catalyst.

    Bokach, D; de la Fuente, J. L. G., Tsypkin, M., Ochal, P., Endsjø, I. C., Tunold, R., Sunde, S. and Seland, F.

    The electrooxidation of methanol was studied at elevated temperature and pressure by cyclic voltammetry and constant potential experiments at real fuel cell electrocatalysts. Ruthenium core and platinum shell nanoparticles were synthesized by a sequential polyol route, and characterized electrochemically by CO stripping at room temperature to quickly confirm the structure of the synthesized core–shell structure as compared to pure commercial Pt/C and Pt–Ru/C alloy catalysts.

  • Dip-coating of 8YSZ nanopowder for SOFC applications

    Hanna Tikkanen; Ilea, Crina Silvia; Wærnhus, Ivar; Alex C. Hoffmann

    A dip-coating method was used to obtain 8YSZ thin films formed from nanoparticles on anode support for SOFC applications. 8YSZ nanopowder was obtained via a modified sol–gel method using sucrose and pectin as organic precursors. The nanoparticles were suspended in ethanol using phosphate ester (PE) and polyvinyl butyral (PVB) as dispersant and binder, respectively.

  • Measurements and 3D simulation of ultrasonic directive beam transmission through a water-immersed steel plate

    Lohne, Kjetil Daae; Lunde, Per; Vestrheim, Magne;

    A 3D full-wave angular spectrum simulation model for reflection and transmission of ultrasonic directive circular piston sound fields, from and through a fluid-immersed isotropic solid plate has been implemented.

  • Finite element analysis of acoustic beam interactions with plate at normal incidence. Comparison with a 3D angular spectrum method and measurements

    Aanes, Magne; Lohne, Kjetil Daae; Lunde, Per; Vestrheim, Magne;

    The use of the finite element method (FEM) for studying the interactions of an acoustic beam with an elastic steel plate is discussed, in comparison with a 3D angular spectrum method (ASM) and measurements.

  • A Simulation Approach to Optimizing Performance of Equipment for Thermostimulation of Muscle Tissue using COMSOL Multiphysics

    Kocbach, Jan; Folgerø, Kjetil; Louise Mohn; Ole Brix

    A multiphysics simulation approach is used in order to analyse and optimize performance of thermostimulation equipment.

  • Visual Analysis of Multivariate Movement Data Using Interactive Difference Views

    Lampe, Ove Daae; Johannes Kehrer, Helwig Hauser

    Movement data consisting of a large number of spatio-temporal agent trajectories is challenging to visualize, especially when all trajectories are attributed with multiple variates. In this paper, we demonstrate the visual exploration of such movement data through the concept of interactive difference views. By reconfiguring the difference views in a fast and flexible way, we enable temporal trend discovery.

  • A Multidirectional Occlusion Shading Model for Direct Volume Rendering

    Solteszova, Veronika; Patel, Daniel; Stefan Bruckner, Ivan Viola

    In this paper, we present a novel technique which simulates directional light scattering for more realistic interactive visualization of volume data. Our method extends the recent directional occlusion shading model by enabling light source positioning with practically no performance penalty.

  • Seismic Volume Visualization for Horizon Extraction

    Patel, Daniel; Stefan Bruckner, Ivan Viola, Meister Eduard Gröller

    Seismic horizons indicate change in rock properties and are central in geoscience interpretation. Traditional interpretation systems involve time consuming and repetitive manual volumetric seeding for horizon growing. We present a novel system for rapidly interpreting and visualizing seismic volumetric data.

  • Volume Visualization based on Statistical Transfer-Function Spaces

    Martin Haidacher; Patel, Daniel; Stefan Bruckner, Armin Kanitsar

    It is a difficult task to design transfer functions for noisy data. In traditional transfer-function spaces, data values of different materials overlap. In this paper we introduce a novel statistical transferfunction space which in the presence of noise, separates different materials in volume data sets.

  • Hydrophobicity patterns and biological adaptation: an exemplary case from fish hemoglobins

    Colafranceschi M; Giuliani A; Andersen Ø; Brix O; De Rosa MC; Giardina B; Colosimo A.

    The dissection of phylogenetic and environmental components in biological evolution is one of the main themes of general biology. Here we propose an approach to this theme relying upon the comparison between a phylogenetic oriented metrics spanning the hemoglobin beta chains of different fishes and a more physiologically oriented metrics defining the same sequences in terms of the dynamical features of their hydrophobic distributions.

  • Time domain finite element modeling of SH-mode propagation in elastic plates with deposits

    Kocbach, Jan; Kippersund, Remi Andre; Per Lunde

    Shear horizontal (SH) mode propagation in a steel plate with a deposit layer of either uniform or non-uniform thickness is considered. The influence of the deposit layer on the received time signals is studied, comparing the uniform and non-uniform thickness deposit layer cases. Time domain finite element simulations are used for the analysis.

  • A cost-effective approach on CO2 emission factor estimation for flare ultrasonic metering systems

    Frøysa, Kjell-Eivind; Hallanger, Anders; Endre Jacobsen and Anders Løvoll Johansen (Statoil ASA)

    In flare gas systems, flow measurement is important both for reports of gas emissions and for process control. Due to the nature of such systems, the flow rates in a flare line varies from very low at normal operations to full flare with very high flow rate in the case of flaring events. This means that a flow metering system for flares typically has to be able to measure flow velocities from 0.1 m/s or less, to more than 100 m/s in order to cover all cases.

  • Combining multibeam-sonar and multifrequency-echosounder data: examples of the analysis and imaging of large euphausiid schools

    Korneliussen, Rolf; Eliassen, Inge Kristian; Heggelund, Yngve; Ola K. Øye, Tor Knutsen, John Dalen

    The first high-resolution, quantitative, multibeam sonar (Simrad MS70) ever developed was mounted in a keel of RV “G. O. Sars” with port-orientated beams. Each ping samples a volume of 60° horizontally × 45° vertically with 500 beams, which is often enough to insonify a complete school of fish or zooplankton.

  • Acoustic species identification of schooling fish

    Korneliussen, Rolf; Eliassen, Inge Kristian; Heggelund, Yngve; Geir O. Johansen

    The development of methods for the acoustic identification of fish is a long-term objective aimed at reducing uncertainty in acoustic-survey estimates. The relative frequency response r(f) measured simultaneously at several frequencies is one of the main acoustic features that characterize the targets, but the relationship between nearest neighbours, school morphology, and environmental and geographical data are also important characteristics in this context.

  • Quantitative assessment of kidney function using dynamic contrast enhanced MRI - steps towards an integrated software prototype

    Anderlik, A. (UiB); Ulvang, Dag Magne; Munthe-Kaas, A.Z. (UiB), Øye, O.K. (CMR), Eikefjord, E. (UiB), Rørvik, J. (UiB/HUS), Zöllner, F.G. (UiB / Univ. Heidelberg), Lundervold, A. (UiB/HUS)

    Renal diseases, caused by e.g. diabetes mellitus, hypertension or multiple cyst formations, can lead to kidney failure that requires renal replacement therapy (RRT). Early detection and treatment can delay or prevent this progression towards end-stage renal disease (ESRD).

  • Expressive Visualization and Rapid Interpretation of Seismic Volumes

    Patel, Daniel;

    One of the most important resources in the world today is energy. Oil and gas provide two thirds of the world energy consumption, making the world completely dependent on it. Locating and recovering the remaining oil and gas reserves will be of high focus in society until competitive energy sources are found.

  • Curve-Centric Volume Reformation for Comparative Visualization

    Lampe, Ove Daae; Carlos Correa, Kwan-Liu Ma, Helwig Hauser

    We present two visualization techniques for curve-centric volume reformation with the aim to create compelling comparative visualizations. A curve-centric volume reformation deforms a volume, with regards to a curve in space, to create a new space in which the curve evaluates to zero in two dimensions and spans its arc-length in the third. The volume surrounding the curve is deformed such that spatial neighborhood to the curve is preserved.

  • Knowledge-assisted visualization of seismic data

    Patel, Daniel; Giertsen, Christopher; Øyvind Sture, Helwig Hauser, M. Eduard Gröller

    We present novel techniques for knowledge-assisted annotation and computer-assisted interpretation of seismic data for oil and gas exploration. We describe the existing procedure for oil and gas search which consists of manually extracting information from seismic data and then aggregating it into knowledge in a detail-oriented bottom-up approach.

  • Moment Curves

    Patel, Daniel; Martin Haidacher, Jean-Paul Balabanian , M. Eduard Gröller

    We define a transfer function based on the first and second statistical moments. We consider the evolution of the mean and variance with respect to a growing neighborhood around a voxel. This evolution defines a curve in 3D for which we identify important trends and project it back to 2D. The resulting 2D projection can be brushed for easy and robust classification of materials and material borders. The transfer function is applied to both CT and MR data.

  • Whether depositing fat or losing weight, fish maintain a balance.

    Brix O; Grüner R; Rønnestad I; Gemballa S.

    In fish, the relative amount of tissues of different densities changes significantly over short periods throughout the year, depending on the availability of food, nutrition and their developmental status, such as sexual maturation. If a land-living animal accumulates fat it influences not only its general state of health, but also markedly increases its energy expenditure for locomotion owing to the force of gravity.

  • Chemical shift based MR imaging and gas chromatography for quantification and localization of fat in Atlantic mackerel

    Ole Brix; Patricia Apablaza; Andrew C. Baker ; Torfinn Taxt ;Renate Grüner

    The purpose of this study was to quantify the content and localization of fat in Atlantic mackerel (N = 17) in order to assess fish quality and understand the bioenergetics of different life stages for this species.

  • Fluid Characterization in a subsea on-line multiphase fluid sampling and analysis sytem

    E.M. Bruvik; Frøysa, Kjell-Eivind; Holstad, Marie Bueie; Stavland, Stian; J. Spilde; B.T. Hjertake; S.K. Meyer

    The trend in subsea petroleum production systems in offshore field developments points towards integrated production and processing facilities at the seabed along with more extensive use of multiphase transportation technology.

  • Nitrogen subtraction on reported CO2 emission using ultrasonic flare gas meter

    Frøysa, Kjell-Eivind; Henning Ekerhovd, StatoilHydro; Atle A. Johannessen, Fluenta

    The CO2 emission from flaring is typically measured by ultrasonic flare gas meters. In order to reduce the CO2 emissions, nitrogen purging is often utilized in situations of low flow in the flare. At such purging conditions, a significant amount of the gas flow in the flare is nitrogen. The CO2 emission data are to be reported to authorities. In order to get a realistic report of the CO2 emissions, the nitrogen purging should be subtracted from the total combustible gas flow.

  • Update on the calibration topic group

    Pedersen, Geir; Toby Jarvis

    Toby Jarvis gave an update on the status of the calibration topic group with specific reference to documenting the calibration procedure of the Simrad EK60 echosounder. The report of the topic group will be posted on the WGFAST web site and made available to the planning groups. The calibration topic group has now concluded with a key outcome that a calibration study group is formed with the intention of commencing at the 2010 WG FAST meeting in San Diego.

  • Target strength of some standard, and so me not - so - standard, targets in fisheries acoustics using the finite element method

    Pedersen, Geir; Penã, H.; Ona, E.

    The finite element method (FEM) is used to calculate target strength of standard targets in fisheries acoustics as a function of frequency and incident sound angle. These targets include spheres, spheroids, and cylinders using different boundary conditions, representing different physical properties of the scatterer. Target strength is also calculated for swimbladder models, chilean jack mackerel (Trachurus symmetricus murphyi), obtained from magnetic resonance imaging.

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