Viser treff 211-230 av 309

    • 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 ...
    • Performance Quantification of Icebreaker Operations in Ice Management by Numerical Simulations 

      Bjørnø, Jon; Skjetne, Roger; van den Berg, Marnix; Lu, Wenjun; Lubbad, Raed; Løset, Sveinung (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-11-15)
      The paper addresses the problem of quantifying and assessing the effectiveness of icebreaker operations in ice management (IM) using a high-fidelity simulator. The numerical model includes an accurate geometric representation of an icebreaker, a cylindrical protected structure, and a synthetic ice environment. A set of key performance indicators (KPIs) are defined and proposed to quantify the ...
    • Perspectives on the economic and political history of the Ross Sea 

      Basberg, Bjørn; Lintott, Bryan John (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-09-07)
      The paper analyses the economic and political history of the Ross Sea, where exploration, science, commercial exploitation, politics and adventure became highly interlinked and interwoven. Expedition accounts and the extensive literature on Antarctic history and politics inform the contextual aspects. The archives of the Norwegian whaling company A/S Rosshavet, established in 1923, and the ...
    • Position prediction of marine seismic streamer cables using various kalman filter methods 

      Grindheim, Jan Vidar; Revhaug, Inge; Pedersen, Egil; Solheim, Peder (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-04-26)
      Towed seismic streamer cables are extensively employed for offshore marine petroleum exploration. With the increasing need for accurate streamer steering due to rising number and length of streamers and decreasing intrastreamer separation, as well as new types of survey configurations, accurate modeling, positioning, and path prediction of the streamers are imperative. In the present study, a variety ...
    • Possible COLREGs Failures under Digital Helmsman of Autonomous Ships 

      Perera, Lokukaluge Prasad; Batalden, Bjørn-Morten (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-10-19)
      Autonomous navigation will play an important role in the future of the shipping industry. Hence, this study illustrates several concepts that should support the navigation side in relation to the collision avoidance of autonomous ships. The concept of system intelligence, i.e., cloned by human navigators, as the digital helmsman to navigate future vessels is discussed in the first part of this study. ...
    • Postural Stability Variables for Dynamic Equilibrium 

      Dutt-Mazumder, Aviroop; Dhar, Sushmit; Dutt-Mazumder, Courtney (Journal article; Tidsskriftartikkel; Peer reviewed, 2018)
      Experiments on the maintenance of postural stability on flat stationary support surfaces (quiet standing) that show only limited modes of the potential configurations of balance stability have dominated investigations of balance in quiet upright standing. Recent studies have revealed coordination properties of the whole body in maintaining dynamic postural stability with the application of moving ...
    • A practical guideline for human error assessment: A causal model 

      Ayele, Yonas Zewdu; Barabadi, Abbas (Konferansebidrag; Conference object, 2017-12-12)
      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 of ...
    • Predicting Breast Cancer Leveraging Supervised Machine Learning Techniques 

      Aamir, Sanam; Rahim, Aqsa; Aamir, Zain; Abbasi, Saadullah Farooq; Khan, Muhammad Shahbaz; Alhaisoni, Majed; Khan, Muhammad Attique; Khan, Khyber; Ahmad, Jawad (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-08-16)
      Breast cancer is one of the leading causes of increasing deaths in women worldwide. The complex nature (microcalcification and masses) of breast cancer cells makes it quite difficult for radiologists to diagnose it properly. Subsequently, various computer-aided diagnosis (CAD) systems have previously been developed and are being used to aid radiologists in the diagnosis of cancer cells. However, due ...
    • Prediction of marine icing incidents in cold regions using an IoT-based device 

      Dhar, Sushmit; Khawaja, Hassan Abbas; Naseri, Masoud; Zhu, Tiantian; Edvardsen, Kåre (Conference object; Konferansebidrag, 2023-12)
    • Prediction of remaining useful life (RUL) of Komatsu excavator under reliability analysis in the Weibull-frailty model 

      Ghomghaleh, Awat; Khaloukakaie, Reza; Ataei, Mohammad; Barabadi, Abbas; Qarahasanlou, Ali Nouri; Rahmani, Omeid; Beiranvand Pour, Amin (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-15)
      It is an essential task to estimate the remaining useful life (RUL) of machinery in the mining sector aimed at ensuring the production and the customer’s satisfaction. In this study, a conceptual framework was used to determine the RUL under the reliability analysis in a frailty model. The proposed framework was implemented on a Komatsu PC-1250 excavator from the Sungun copper mine. Also, the ...
    • 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 ...
    • Preliminary Hazard Analysis for UAV-assisted Bridge Inspection 

      Ayele, Yonas Zewdu; Ashrafi, Behrooz (Journal article; Tidsskriftartikkel; Peer reviewed, 2020)
      Unmanned aerial vehicle (UAV) technology has found its way into a number of civilian applications in the last 20 years, predominantly due to lower costs and tangible scientific improvements. In its application to structural bridge inspection, UAVs provide two main functions. The first, being the most common, detects damage through visual sensors. The 2D imagery data can be used to quickly ...
    • Proactive Collision Avoidance for Autonomous Ships: Leveraging Machine Learning to Emulate Situation Awareness 

      Murray, Brian; Perera, Lokukaluge Prasad (Journal article; Tidsskriftartikkel; Peer reviewed, 2021)
      Autonomous ship technology is developing at a rapid pace, with the aim of facilitating safe ship operations. Collision avoidance is one of the most critical tasks that autonomous ships must handle. To support the level of safety associated with collision avoidance, this study suggests to provide autonomous ships with the ability to conduct proactive collision avoidance maneuvers. Proactive collision ...
    • Probability distributions for wind speed volatility characteristics: A case study of Northern Norway 

      Chen, Hao; Anfinsen, Stian Normann; Birkelund, Yngve; Yuan, Fuqing (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-11)
      The Norwegian Arctic is rich in wind resources. The development of wind power in this region can boost green energy and also promote local economies. In wind power engineering, it is a tremendous advantage to base projects on a sound understanding of the intrinsic properties of wind resources in an area. Wind speed volatility, a phenomenon that strongly affects wind power generation, has not received ...
    • 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 ...
    • The process of integrating risk management: usefulness, standardisation and adaptation 

      Leonhardsen, Mette; Nilsen, Aud Solveig; Olsen, Odd Einar Falnes (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-08-25)
      In this paper we analyse how a municipality set out to integrate risk management throughout an organisation with more than 9000 employees in six divisions and over 100 sub-units. An objective was to ensure coherence in risk management related work conducted in various sub-units in the municipality. Being forerunners, those involved had to find their own way. We identify three focus areas of importance ...
    • The pure PV-EV energy system – A conceptual study of a nationwide energy system based solely on photovoltaics and electric vehicles 

      Boström, Tobias; Babar, Bilal; Hansen, Jonas Berg; Good, Clara (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-08)
      The objective of this conceptual study is to reveal the substantial potential and synergy of solar energy and electric vehicles (EVs) working together. This potential is demonstrated by studying the feasibility of a nationwide energy system solely reliant on solar energy and EVs. Photovoltaic (PV) solar energy is already an important energy source globally, but due to its intermittency it requires ...
    • Quantifying the effects of watershed subdivision scale and spatial density of weather inputs on hydrological simulations in a Norwegian Arctic watershed 

      Bui, Minh Tuan; Lu, Jinmei; Nie, Linmei (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-12-01)
      The effects of watershed subdivisions on hydrological simulations have not been evaluated in Arctic conditions yet. This study applied the Soil and Water Assessment Tool and the threshold drainage area (TDA) technique to evaluate the impacts of watershed subdivision on hydrological simulations at a 5,913-km<sup>2 </sup>Arctic watershed, Målselv. The watershed was discretized according to four TDA ...
    • A rather wild imagination: who is and who is not a migrant in the Czech media and society? 

      Bartoszewicz, Monika Gabriela; Eibl, Otto (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-07-06)
      This paper focuses on migrants and migration in the context of the Czech Republic, an ethnically and nationally homogeneous country without significant migration experience. Despite this fact, the issue of migration became very prominent in 2015 and has been an integral part of Czech political and public discourse since then. Although the topic has attracted scholarly interest, but the reflection ...
    • Real-Time Ship Draft Measurement and Optimal Estimation Using Kalman Filter 

      Dhar, Sushmit; Khawaja, Hassan Abbas (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-02)
      Ship operators typically depend on the visual method for draft reading, which may lead to errors or approximations, and it further introduces draft survey calculation errors and can not provide continuous updates. Ensuring accurate real-time ship draft measurement becomes crucial for enhancing navigational safety, optimizing vessel performance, and achieving precise cargo and consumable measurements. ...