Now showing items 201-220 of 527

    • 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 ...
    • An Evaluation on Diverse Machine Learning Algorithms for Hourly Univariate Wind Power Prediction in the Arctic 

      Chen, Hao; Birkelund, Yngve (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-12-23)
      Wind power forecasting is crucial for wind power systems, grid load balance, maintenance, and grid operation optimization. The utilization of wind energy in the Arctic regions helps reduce greenhouse gas emissions in this environmentally vulnerable area. In the present study, eight various models, seven of which are representative machine learning algorithms, are used to make 1, 2, and 3 step ...
    • Evaluation of the Climate Forecast System Reanalysis data for hydrological model in the Arctic watershed Målselv 

      Bui, Minh Tuan; Lu, Jinmei; Nie, Linmei (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-13)
      The high-resolution Climate Forecast System Reanalysis (CFSR) data have recently become an alternative input for hydrological models in data-sparse regions. However, the quality of CFSR data for running hydrological models in the Arctic is not well studied yet. This paper aims to compare the quality of CFSR data with ground-based data for hydrological modeling in an Arctic watershed, Målselv. The ...
    • A discipline without a name? Contrasting three fields dealing with hazards and disaster 

      Staupe-Delgado, Reidar; Abdel-Fattah, Dina; Pursiainen, Christer Henrik (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-29)
      A growing number of research fields have been striving for recognition as an academic discipline. Rather than argue that ‘our field’ should also be recognised as such, we stop to ask two fundamental questions. Our first question concerns whether and how disciplinary concerns would benefit research fields dealing with hazards and disasters. Second, we reflect on the implications of not having a broadly ...
    • Vanadium removal from mining ditch water using commercial iron products and ferric groundwater treatment residual-based materials 

      Zhang, Ruichi; Lu, Jinmei; Dopson, Mark; Leiviskä, Tiina (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-08-06)
      Removal of vanadium from liquid waste streams protects the environment from toxic vanadium species and promotes the recovery of the valuable metal. In this study, real mining ditch water was sampled from a closed vanadium mine (V–Fe–Ti oxide deposit, Finland) and used in sorption experiments at prevailing vanadium concentration (4.66–6.85 mg/L) and pH conditions (7.02–7.83). The high concentration ...
    • Impact of temperature on the leaching of sulphate, Co, Fe, Mn, Ni and Zn from the Ballangen tailings deposit, Norway: A laboratory column experiment 

      Lu, Jinmei; Walder, Ingar; Leiviskä, Tiina (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-29)
      Temperature is an important factor affecting the leaching of contaminants from waste deposits, especially in the Nordic region where temperature change is more drastic than other areas. In this study, the impact of temperature variation in the leaching of sulphate, Co, Fe, Mn, Ni and Zn from the Ballangen tailings deposit, northern Norway, was investigated using a column leaching experiment. ...
    • International collaboration for meeting the challenges of huge and cascading disasters 

      Nilsen, Aud Solveig; Stakkeland, Linda Marie (Conference object; Konferansebidrag, 2021-09)
      Some crisis have an international impact. How is it possible to enhance collaboration between nations in huge and cascading disasters? We will present Barents Rescue (BR) as an inspiration for our Student Barents Rescue (SBR) and thereafter show examples from a student pilot with an international scenario.
    • How and why develop scenarios for training students to use their knowledge in practice? 

      Nilsen, Aud Solveig (Conference object; Konferansebidrag, 2021-09)
      To be able to handle crisis and risks there is a need for different skills. We will focus on learning by combining theory and practice. Since NEEDS is a disaster management community, scenarios in line with this theme are wanted.<p> <p>This colloquium can be an experience transfer between educators that work with scenario-based training and want to develop this further. Drawing on different ...
    • 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 ...
    • Recoverability modeling of power distribution systems using accelerated life models: Case of power cut due to extreme weather events in Norway 

      Rød, Bjarte; Barabadi, Abbas; Naseri, Masoud (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-09)
      Today’s societies rely on electric power distribution systems. Recent weather events have illustrated that the loss of such service can lead to severe consequences for societies and stakeholders. Hence, to reduce the impact of such extreme events on infrastructure systems and limit the associated losses, it is crucial to design infrastructure that can bounce back and recover rapidly after disruptions ...
    • Lumped, constrained cable modeling with explicit state-space formulation using an elastic version of Baumgarte stabilization 

      Skjong, Stian; Reite, Karl-Johan; Aarsæther, Karl Gunnar (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-29)
      This paper presents a modeling approach for efficient simulation of slender structures, such as wires, cables and ropes. Lumped structural elements are connected using constraints. These are solved explicitly, using an elastic version of Baumgarte stabilization. This avoids singularities in the matrix inversions. The resulting explicit state-space formulation filters the higher order dynamics and ...
    • Experimental and simulated evaluations of airborne contaminant exposure in a room with a modified localized laminar airflow system 

      Cheng, Zhu; Aganovic, Amar; Cao, Guangyu; Bu, Zhongming (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-02-15)
      The traditional mixing ventilation is not an energy effective approach to remove indoor air pollutants, maintain breath zone air quality, and control the airborne transmission. This study investigated the potential of a localized laminar airflow ventilation system to alleviate human exposure to pollutants. Breathing thermal manikins with sitting posture and supine posture were used to simulate the ...
    • An Slow Motion Detection Algorithm using High Order Statistic Approach 

      Yuan, Fuqing; Lu, Jinmei (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-16)
      Motion detection is vital for consumer electronics and the Internet of things (IOT). For a scenario where the motion is slow and gentle, the resolution of the motion sensor is critical for the detection, while the algorithm development is another critical issue to differentiate the motion signal from noise measurement. This paper investigates the feasibility of using higher order statistics ...
    • 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 ...
    • Data-augmented sequential deep learning for wind power forecasting 

      Chen, Hao; Birkelund, Yngve; Qixia, Zhang (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-11-15)
      Accurate wind power forecasting plays a critical role in the operation of wind parks and the dispatch of wind energy into the power grid. With excellent automatic pattern recognition and nonlinear mapping ability for big data, deep learning is increasingly employed in wind power forecasting. However, salient realities are that in-situ measured wind data are relatively expensive and inaccessible and ...
    • Simulation of peak tension loads in Subsea power cables during installation 

      Okkerstrøm, Lene; Gudmestad, Ove Tobias; Pedersen, Egil (Journal article; Tidsskriftartikkel; Peer reviewed, 2021)
      At present, most of the insurance claims in the offshore wind industry are due to cable failures where a large percentage occurs during the installation of the array and export cables. As the reliability of the cables depends on the location and installation method, it is important to map the risks involved, which can compromise the cable's integrity in individual projects. This paper presents ...
    • A methodology for collecting donning times of thermal protective immersion suits intended to be worn by passengers on vessels operating in cold environments 

      Brünig, Ria; Galea, Edwin R; Batalden, Bjørn-Morten; Oltedal, Helle Asgjerd (Journal article; Tidsskriftartikkel; Peer reviewed, 2021)
      Adequate thermal protection for passengers travelling on-board vessels in cold climate regions, such as that provided by thermal protective immersion suits (TPIS), enhances passenger survivability in emergency situations, in particular those requiring the abandonment of the vessel. As emergency abandonment is a time critical process, it is essential to consider the time required to correctly don the ...
    • Examination of turbulence impacts on ultra-short-term wind power and speed forecasts with machine learning 

      Chen, Hao; Birkelund, Yngve; Yuan, Fuqing (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-11-25)
      Wind turbines’ economic and secure operation can be optimized through accurate ultra-short-term wind power and speed forecasts. Turbulence, considered as a local short-term physical wind phenomenon, affects wind power generation. This paper investigates the use of turbulence intensity for ultra-short-term predictions of wind power and speed with a wind farm in the Arctic, including and excluding ...
    • 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 ...
    • Biosignal-Based Driving Skill Classification Using Machine Learning: A Case Study of Maritime Navigation 

      Xue, Hui; Batalden, Bjørn-Morten; Sharma, Puneet; Johansen, Jarle André; Prasad, Dilip K. (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-19)
      This work presents a novel approach to detecting stress differences between experts and novices in Situation Awareness (SA) tasks during maritime navigation using one type of wearable sensor, Empatica E4 Wristband. We propose that for a given workload state, the values of biosignal data collected from wearable sensor vary in experts and novices. We describe methods to conduct a designed SA task ...