Geir Anton Johansens bilde
Geir Anton
Johansen
Professor II
Besøksadresse: 
Allegt. 55
5020 BERGEN
Postadresse: 
Postboks 7803
5020 BERGEN
Telefon: 
+47 55 58 27 60
+47 911 43 615
Last ned visittkort
  • Radiation physics
  • Measurement science
  • Multiphase process measurements
  • Industrial tomography
Bøker
  • Johansen, Geir Anton; Jackson, Peter. 2004. Radioisotope Gauges for Industrial Process Measurements. John Wiley & Sons. 334 sider. ISBN: 0-471-48999-9.
Tidsskriftartikler
  • Meric, Ilker; Johansen, Geir Anton; Malta Moreira, Icaro Valgueiro. 2014. A library least-squares approach for scatter correction in gamma-ray tomography. Radiation Physics and Chemistry. 108: 39-47. doi: 10.1016/j.radphyschem.2014.11.013
  • Meric, Ilker; Johansen, Geir Anton; Mattingly, John; Gardner, Robin Pierce. 2014. On the ill-conditioning of the multiphase flow measurement by prompt gamma-ray neutron activation analysis. Radiation Physics and Chemistry. 95: 401-404. doi: 10.1016/j.radphyschem.2012.12.047
  • Sætre, Camilla; Tjugum, Stein-Arild; Johansen, Geir Anton. 2014. Tomographic segmentation in multiphase flow measurement. Radiation Physics and Chemistry. 95: 420-423. doi: 10.1016/j.radphyschem.2013.03.025
  • Thorn, Richard; Johansen, Geir Anton; Hjertaker, Bjørn Tore. 2013. Three-phase flow measurement in the petroleum industry. Measurement science and technology. 24. 17 sider. doi: 10.1088/0957-0233/24/1/012003
  • Meric, Ilker; Johansen, Geir Anton; Holstad, Marie Bueie; Calderon, Adan F.; Gardner, Robin Pierce. 2012. Enhancement of the intrinsic gamma-ray stopping efficiency of Geiger–Muller counters. Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment. 696: 46-54. doi: 10.1016/j.nima.2012.08.086
  • Meric, Ilker; Johansen, Geir Anton; Holstad, Marie Bueie; Mattingly, John; Gardner, Robin Pierce. 2012. On the treatment of ill-conditioned cases in the Monte Carlo library least-squares approach for inverse radiation analyzers. Measurement science and technology. 23. doi: 10.1088/0957-0233/23/5/055603
  • Sætre, Camilla; Johansen, Geir Anton; Tjugum, Stein-Arild. 2012. Tomographic multiphase flow measurement. Applied Radiation and Isotopes. 70: 1080-1084. doi: 10.1016/j.apradiso.2012.01.022
  • Hjertaker, Bjørn Tore; Maad, Rachid; Johansen, Geir Anton. 2011. Dual-mode capacitance and gamma-ray tomography using the Landweber reconstruction algorithm. Measurement science and technology. 22. 7 sider. doi: 10.1088/0957-0233/22/10/104002
  • Meric, Ilker; Johansen, Geir Anton; Holstad, Marie Bueie; Gardner, Robin Pierce. 2011. Monte Carlo modelling of gamma-ray stopping efficiencies of Geiger-Muller counters. Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment. 636: 61-66. doi: 10.1016/j.nima.2011.01.083
  • Meric, Ilker; Johansen, Geir Anton; Holstad, Marie Bueie; Lee, Kyoung O.; Calderon, Adan F.; Wang, Jiaxin; Gardner, Robin Pierce. 2011. A single scatter electron Monte Carlo approach for simulating gamma-ray stopping efficiencies of Geiger-Müller counters. Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment. 654: 279-287. doi: 10.1016/j.nima.2011.06.065
  • Meric, Ilker; Johansen, Geir Anton; Holstad, Marie Bueie; Wang, Jiaxin; Gardner, Robin Pierce. 2011. Produced water characterization by prompt gamma-ray neutron activation analysis. Measurement science and technology. 22. 10 sider. doi: 10.1088/0957-0233/22/12/125701
  • Mosorov, V.; Johansen, Geir Anton; Maad, Rachid; Sankowski, D. 2011. Monte Carlo simulation for multi-channel gamma-ray process tomography. Measurement science and technology. 22. 10 sider. doi: 10.1088/0957-0233/22/5/055502
  • Johansen, Geir Anton; Hampel, Uwe; Hjertaker, Bjørn Tore. 2010. Flow imaging by high speed transmission tomography. Applied Radiation and Isotopes. 68: 518-524. doi: 10.1016/j.apradiso.2009.09.004
  • Maad, Rachid; Hjertaker, Bjørn Tore; Johansen, Geir Anton; Olsen, Øystein. 2010. Dynamic characterization of a high speed gamma-ray tomograph. Flow Measurement and Instrumentation. 21: 538-545. doi: 10.1016/j.flowmeasinst.2010.10.001
  • Sætre, Camilla; Johansen, Geir Anton; Tjugum, Stein-Arild. 2010. Salinity and flow regime independent multiphase flow measurements. Flow Measurement and Instrumentation. 21: 454-461. doi: 10.1016/j.flowmeasinst.2010.06.002
  • Johansen, Geir Anton; Taxt, Randi Elisabeth. 2009. Næringslivet + UiB er en mulighet. Bergens Tidende. Publisert 2009-03-25.
  • Hjertaker, Bjørn Tore; Maad, Rachid; Schuster, Erik; Almås, Ole Andreas; Johansen, Geir Anton. 2008. A data acquisition and control system for high-speed gamma-ray tomography. Measurement science and technology. 19. 9 sider. doi: 10.1088/0957-0233/19/9/094012
  • Johansen, Geir Anton. 2008. UiB og næringslivet. Bergens Tidende. Publisert 2008-10-14.
  • Johansen, Geir Anton; Wang, Mi. 2008. Industrial process tomography. Measurement science and technology. 19. 1 sider. doi: 10.1088/0957-0233/19/9/090101
  • Maad, Rachid; Hjertaker, Bjørn Tore; Johansen, Geir Anton. 2008. Semi-empirical scatter correction model for high-speed gamma-ray tomography. Measurement science and technology. 19. 6 sider. doi: 10.1088/0957-0233/19/9/094016
  • Maad, Rachid; Johansen, Geir Anton. 2008. Experimental analysis of high-speed gamma-ray tomography performance. Measurement science and technology. 19: 10. doi: 10.1088/0957-0233/19/8/085502
  • Vagle, Oddbjørn; Olsen, Øystein; Johansen, Geir Anton. 2007. A simple and efficient active quenching circuit for Geiger-Muller counters. Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment. 580: 358-361. doi: 10.1016/j.nima.2007.05.178
  • Dyakowski, Tom; Johansen, Geir Anton; Hjertaker, Bjørn Tore; Sankowski, Dominik; Mosorov, Volodymyr; Wlodarczyk, Jaroslaw. 2006. A dual modality tomography system for imaging gas/solids flows. Particle & particle systems characterization. 23: 260-265. doi: 10.1002/ppsc.200601057
  • Johansen, Geir Anton; Lien, Jan Reinert. 2006. Nettverksrekruttering til matematikk, naturvitenskap og teknologinen. Forskerforum. 8. 34-35.
  • Hjertaker, Bjørn Tore; Tjugum, Stein-Arild; Hammer, Erling A.; Johansen, Geir Anton. 2005. Multimodality tomography for multiphase hydrocarbon flow measurements. IEEE Sensors Journal. 5: 153-160.
  • Holstad, Marie Bueie; Johansen, Geir Anton. 2005. Produced water characterization by dual modality gamma-ray measurements. Measurement science and technology. 16: 1007-1013.
  • Holstad, Marie Bueie; Johansen, Geir Anton; Jackson, Peter; Eidsnes, Kjetil Skippervik. 2005. Scattered gamma radiation utilized for level measurements in gravitational separators. IEEE Sensors Journal. 5: 175-182.
  • Johansen, Geir Anton. 2005. Nuclear tomography methods in industry. Nuclear Physics A. 752: 696-705.
  • Holstad, Marie Bueie; Jackson, Peter; Johansen, Geir Anton. 2004. Scattered gamma-radiation utilized to measure remnant fresh absorbent in absorbent beds. Measurement science and technology. 15: 1827-1834.
  • Johansen, Geir Anton; Hansen, Jan Petter. 2004. Om HiB-UiB-samarbeid og kjøttkvalitet. Bergens Tidende. Publisert 2004-11-16.
  • Tjugum, Stein Arild; Johansen, Geir Anton; Bueie Holstad, Marie. 2003. A multiple voxel model for scattered gamma radiation in pipe flow. Measurement science and technology. 14: 1777-1782.
  • Tjugum, Stein Arild; Frieling, Joop; Johansen, Geir Anton. 2002. A compact low energy multibeam gamma-ray densitometer for pipe-flow measurements. Nuclear Instruments and Methods in Physics Reseach B. 197: 301-309.
  • Tjugum, Stein Arild; Hjertaker, Bjørn Tore; Johansen, Geir Anton. 2002. Multiphase flow regime identification by multibeam gamma-ray densitometry. Measurement science and technology. 13: 1319-1326.
  • Hjertaker, Bjørn Tore; Johansen, Geir Anton; Jackson, Peter. 2001. Level measurement and control strategies for subsea separators. Journal of Electronic Imaging (JEI). 10: 679-689.
  • Holstad, Marie Bueie; Tjugum, Stein Arild; Johansen, Geir Anton. 2000. Dual modality Densitometry (DMD) - for salinitetsuavhengig måling av gassfraksjon i olje/vann/gass-rørstrømning. Elektronikk : tidsskrift for IT og telekom. 7/8.
  • Johansen, Geir Anton; Jackson, Peter. 2000. Salinity independent measurement of gas volume fraction in oil/gas/water pipe flows. Applied Radiation and Isotopes. 53: 595-601.
  • Åbro, Eirik; Johansen, Geir Anton; Opedal, Helge. 1999. A radiation transport model as a design tool for gamma densitometers. Nuclear Instruments and Methods in Physics Research A. 431: 347-355.
  • Åbro, Eirik; Khoryakov, V.A.; Johansen, Geir Anton; Kocbach, Ladislav. 1999. Determination of void fraction and flow regime using a neural network trained on simulated data based on gamma-ray densitometry. Measurement science and technology. 10: 619-630.
  • Åbro, Eirik; Johansen, Geir Anton. 1998. Improved void fraction determination by means of multibeam gamma-ray attenuation measurments. Flow Measurement and Instrumentation. 10: 100-108.
  • Hammer, Erling A.; Johansen, Geir Anton. 1997. Process Tomography in Oil Industry - State of the Art and Future Possibilities. Measurement and control (London. 1968). 30: 212-216.
  • Mwambela, Alfred John; Isaksen, Øyvind; Johansen, Geir Anton. 1997. The use of entropic thresholding methods in reconstruction of capacitance tomography data. Chemical Engineering Science. 52: 2149-2159.
  • Thorn, R; Johansen, Geir Anton; Hammer, Erling A. 1997. Resent developments in three -phase flow measurement. Measurement science and technology.
Rapporter/avhandlinger
  • Birkeland, Ingebjørg; Prestegård, Linda; Johansen, Geir Anton. 2009. Muligheter for tettere samarbeid med institusjoner i Midtvesten. SiU Senter for internasjnalisering av høyere utdanning. 25 sider.
  • Johansen, Geir Anton; Legoupil, Samuel; Cassanello Fernandez, Miryan; Hamada, Margarida; Thyn, Jiri; Kim, Jong-Bum; Sipaun, Susan Maria; Sankowski, Dominik; Abdullah, Jaafar; Dudukovic, Mike; Nowakowski, Jazek; Ramirez-Garcia, Fernandez; Mesquita, Carlos; Maad, Rachid. 2008. Industrial Process Gamma Tomography. International Atomic Energy Agency, Vienna. 153 sider.
  • Johansen, Geir Anton; Legoupil, Samuel; Fernandez, Miryan C. Cassanello; Hamada,, Margarida Mizue; Thyn, Jiri; Kim, Jong-Bum; Sipaun, Susan Maria; Sankowski, Dominik; Dudukovic, Milorad. 2006. Industrial process gamma tomography - 3rd RCM Report. International Atomic Energy Agency, Wien. 21 sider.
  • Tjugum, Stein Arild; Johansen, Geir Anton. 2002. Feasibility tests of using a fluorescence X-ray tube in a pipe-flow densitometer. Scientific/technical report (Universitetet i Bergen. Fysisk institutt). 2001-01. MANGLER. 10 sider.
  • Spilde, Asbjørn; Johansen, Geir Anton. 2001. VLSI radiation detector electronics and its application to tomography. Scientific/ Technical Report. 2001-03. Fysisk institutt. 18 sider.
  • Tjugum, Stein Arild; Johansen, Geir Anton. 2001. Compact gamma-ray densitometer for pipe flow measurements - a feasibility study. Scientific/technical report (Universitetet i Bergen. Fysisk institutt). 2001-01. Department of Physics, University of Bergen, Bergen. 21 sider.
  • Tjugum, Stein Arild; Johansen, Geir Anton. 2001. MiniGamma - a compact gamma-ray densitometer. Scientific/technical report (Universitetet i Bergen. Fysisk institutt). 2001-08. Department of Physics, University of Bergen, Bergen. 21 sider.
  • Johansen, Geir Anton; Holstad, Marie Bueie. 2000. Geiger Müller tubes in gamma-ray densitometry - a feasibility study. Scientific/ Technical Report. 2000-01. Fysisk institutt, Universitetet i Bergen, Bergen. 8 sider.
  • Johansen, Geir Anton. 1998. Guidelines for graduate students - hints and help about project management and reporting. Internal Report/ Compendium. 1998-01. Fysisk institutt, UiB.
  • Åbro, E; Johansen, Geir Anton. 1998. The use of Multiple Gamma-Beams for Monitoring and Control of Down-hole Hydrocyclone Separators. Scientific/ Technical Report. 03-1998. Fysisk institutt, UiB.
  • Johansen, Geir Anton. 1990. Development and analysis of silicon based detectors for low energy nuclear radiation. 1 sider.
Bokkapitler
  • Hammer, Erling A.; Johansen, Geir Anton; Dyakowski, T; Roberts, E P L; Cullivan, J C; Williams, R A; Hassan, Y A; Claiborn, C S. 2005. Advanced experimental techniques. Chapter 14, sider . I:
    • Crowe, Clayton T. 2005. Multiphase Flow Handbook. Taylor & Francis. 1156 sider. ISBN: 0849312809.
  • Åbro, Eirik; Johansen, Geir Anton. 1998. The use of Multiple Gamma-Beams for Monitoring and Control of Down-hole Hydrocyclone Separators. 8 s. I:
    • [Mangler etternavn], [Mangler fornavn]. 1998. Scientific/Technical Report. Fysisk institutt, Universitetet i Bergen.

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