Now showing items 73-92 of 106

    • Performance of an Ultrasonic Imaging System Based on a 45-MHz Linear PVDF Transducer Array: A Numerical Study 

      Brodal, Eivind; Melandsø, Frank; Jacobsen, Svein Ketil (Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
      New designs of high-resolution ultrasonic imaging systems that operate in the 30–100MHz region, for example, those based on linear transducer systems, are currently being investigated for medical purposes. Acoustic waves with frequencies in this range can detect microscopic structures in human tissue but will typically only penetrate a few mm because of large attenuation. However, this is sufficient ...
    • A practical guideline for human error assessment: A causal model 

      Ayele, Yonas Zewdu; Barabadi, Abbas (Peer reviewed; Konferansebidrag; Conference object, 2017-12-12)
      Abstract: To meet the availability target and reduce system downtime, effective maintenance have a great importance. However, maintenance performance is greatly affected in complex ways by human factors. Hence, to have an effective maintenance operation, these factors needs to be assessed and quantified. To avoid the inadequacies of traditional human error assessment (HEA) approaches, the application ...
    • Prediction of the long-term performance of green liquor dregs as a sealing layer to prevent the formation of acid mine drainage 

      Mäkitalo, Maria; Lu, Jinmei; Maurice, Christian; Öhlander, Björn (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-08)
      One of the mining industry's main concerns is the management of waste rock and tailings generated by sulfide ore extraction. Upon exposure of atmospheric oxygen, iron sulfides oxidize generating acidity. Infiltrating water form a metal-rich acidic leachate called acid mine drainage (AMD), that can cause serious environmental problems. Green liquor dregs (GLD) is a material that resists the passage ...
    • Probability mapping of scarred myocardium using texture and intensity features in CMR images 

      Kotu, Lasya Priya; Engan, Kjersti; Skretting, Karl; Måløy, Frode; Ørn, Stein; Woie, Leik; Eftestøl, Trygve (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      The myocardium exhibits heterogeneous nature due to scarring after Myocardial Infarction (MI). In Cardiac Magnetic Resonance (CMR) imaging, Late Gadolinium (LG) contrast agent enhances the intensity of scarred area in the myocardium. In this paper, we propose a probability mapping technique using Texture and Intensity features to describe heterogeneous nature of the scarred myocardium in Cardiac ...
    • Review of Peltier and Resistive Heating Elements through Infrared Imaging 

      Taimur, Madiha; Rashid, Taimur; Khawaja, Hassan Abbas (Conference object; Konferansebidrag, 2016-12-08)
      The study includes the review of the heating elements to develop the fundamental understanding. The heating elements to be investigated are Peltier and Resistive types. Both have different working principles and they are used in various industrial applications for cooling and heating purposes. The Infrared (IR) wavelength is emitted by each object at a temperature above absolute zero. IR light is ...
    • Review of the phenomenon of fluidization and its numerical modelling techniques 

      Khawaja, Hassan Abbas (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-24)
    • Review of the Phenomenon of Ice Shedding from Wind Turbine Blades 

      Xue, Hui; Khawaja, Hassan Abbas (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-29)
      Wind power is a sustainable source of energy. However, there are certain challenges to be overcome. One of the operational challenges is the phenomenon of ice shedding. Icing happens on wind turbine blades in cold regions. When ice grows to a certain size, it separates from the wind turbine blades resulting in the phenomenon of ice shedding. This phenomenon is of significantly dangerous for equipment ...
    • Risikostyring i kommuner? 

      Nilsen, Aud Solveig (Research report; Forskningsrapport, 2013)
    • Risk Assessment of Hazards Due to the Installation and Maintenance of Onshore Wind Turbines 

      Mustafa, Albara Mohamad Yazid Faisal; Mahadin, Aziz (Peer reviewed; Book; Chapter, 2018-06-11)
      In this work, an assessment of four types of risks is carried out for wind turbines during four phases, namely: transportation, installation, operation and maintenance. This work mainly focuses on onshore type of wind turbines and briefly mentioning the offshore wind turbines. The introduction gives an overview of the main parts and components of wind turbine, in addition to discussing the process ...
    • Risk governance - a more procedural view 

      Nilsen, Aud Solveig (Conference object; Konferansebidrag, 2014)
    • Risk management and governance - a more procedural view 

      Nilsen, Aud Solveig (Conference object; Konferansebidrag, 2001)
    • Selection of a high performance alloy for gas turbine blade using multiphysics analysis 

      Khawaja, Hassan Abbas; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-04-03)
      With the extensive increase in the utilization of energy resources in the modern era, the need of energy extraction from various resources has pronounced in recent years. Thus comprehensive efforts have been made around the globe in the technological development of turbo machines where means of energy extraction is energized fluids. This development led the aviation industry to power boost due to ...
    • Ship Performance and Navigation Data Compression and Communication under Autoencoder System Architecture 

      Perera, Lokukaluge Prasad; Mo, Brage (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-04-21)
      Modern vessels are designed to collect, store and communicate large quantities of ship performance and navigation information through complex onboard data handling processes. That data should be transferred to shore based data centers for further analysis and storage. However, the associated transfer cost in large-scale data sets is a major challenge for the shipping industry, today. The same cost ...
    • Ship speed power performance under relative wind profiles in relation to sensor fault detection 

      Perera, Lokukaluge Prasad; Mo, Brage (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-11-19)
      Statistical Data analysis and visualization approaches to identify ship speed power performance under relative wind (i.e. apparent wind) profiles are considered in this study. Ship performance and navigation data of a selected vessel are analyzed, where various data anomalies, i.e. sensor related erroneous data conditions, are identified. Those erroneous data conditions are investigated and several ...
    • Shipping oil from the Russian Arctic: Past experiences and future prospects 

      Bambulyak, Alexei; Sydnes, Are K.; Milakovic, Aleksandar-Sasa; Frantzen, Bjørn (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-06)
      Transport of oil from Russian Arctic ports to Western markets was insignificant prior to 2002. In 2002, there was a major surge, with 5 million tonnes delivered westwards through the Barents Sea. By 2004, this had increased to 12 million tonnes. Since then, annual volumes have been on levels between 9 and 15 million tonnes. In the near future, the flow of oil cargo in the Arctic may rise ...
    • Shock Tube. Detail overview of equipment and instruments in the shock tube experimental setup 

      Khawaja, Hassan Abbas; Kapaya, Juma; Moatamedi, Mojtaba (Book; Bok, 2015)
      The shock tube is a device in which a normal shock wave is produced by the interaction of fluids at significantly high-pressure difference. The shock tube is comprised of two sections known as driver and driven sections. These two sections are interacted with the high-speed valve or a bursting disc. When the interaction happens, a shock wave forms almost instantaneously and propagates into the driven ...
    • Solution of Pure Scattering Radiation Transport Equation using Finite Difference Method 

      Khawaja, Hassan Abbas (Conference object; Konferansebidrag, 2016-12)
      Radiative transfer is the physical phenomenon of energy transfer in the form of electromagnetic radiation. The propagation of radiation through a medium is affected by absorption, emission, and scattering processes. Equations of radiative transfer have application in a wide variety of subjects including optics, astrophysics, atmospheric science, and remote sensing. Analytic solutions to the radiative ...
    • Spare Part Transportation Management in High North 

      Ayele, Yonas Zewdu; Barabadi, Abbas; Markeset, Tore (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      The demanding physical conditions of the Arctic, remote location, and uncertainty regarding the travel time can both heighten the challenges related to transportation of spare part in the region. Managing to get the appropriate path for transportation of spare parts for oil and gas industries in the region, is one of the major and demanding tasks. In this paper we develop the concept of ...
    • Spatiotemporal patterns of particulate matter (PM) and associations between PM and mortality in Shenzhen, China 

      Zhang, Fengying; Liu, Xiaojian; Zhou, Lei; Yu, Yong; Wang, Li; Lu, Jinmei; Wang, Wuyi; Krafft, Thomas (Peer reviewed, 2016-03-02)
      Background: Most studies on air pollution exposure and its associations with human health in China have focused on the heavily polluted industrial areas and/or mega-cities, and studies on cities with comparatively low air pollutant concentrations are still rare. Only a few studies have attempted to analyse particulate matter (PM) for the vibrant economic centre Shenzhen in the Pearl River Delta. ...
    • Study of Acoustics Properties of SK One Component Polyurethane and its Application in Arctic Marine Structures 

      Xue, Hui; Khawaja, Hassan Abbas; Moatamedi, Mojtaba; Sun, Zhiheng; Souli, Mhmed (Conference object; Konferansebidrag, 2016-12-08)
      Marine noise reduction tends to be challenging and requires a comprehensive engineering approach. The soundproofing materials for marine noise reduction are usually exposed to high temperatures, potential fluid or oil spills, engine maintenance and a high airflow environment. This work looks into the acoustic proofing properties of a non-toxic material ‘SK One Component Polyurethane’ developed by ...