Now showing items 181-200 of 311

    • Road Transportation Challenges in the Arctic 

      Barjouei, A. Shojaei; Gudmestad, Ove T.; Barabady, Javad (Journal article; Tidsskriftartikkel; Peer reviewed, 2020)
      Despite all efforts to mitigate global warming, its rate and magnitude are still rising where transportation is considered to be an important contributor. In the Arctic regions however, unstable weather conditions, strong seasonal variations, and long harsh winters result in additional challenges to transportation in different ways such as those related to environment, human health, safety, and ...
    • Trends in seismic data acquisition in areas with surface ice 

      Hussain, Azeem; Gudmestad, Ove Tobias; Barabady, Javad (Peer reviewed; Bok; Chapter, 2019)
      The Arctic has great significance in relation to the exploration and exploitation of its huge petroleum resources. Seismic surveys are the key part of petroleum exploration. Reflected sound waves are used to produce a 3D subsurface geological model, which helps to take a decision on drilling location for potential hydrocarbon resources. Seismic surveys are very complex operations, and growing energy ...
    • The Compliance Challenges in Emissions Control Regulations to Reduce Air Pollution from Shipping 

      Bui, Khanh Quang; Perera, Lokukaluge Prasad (Peer reviewed; Chapter; Bokkapittel, 2019-10-14)
      One of the thorny problems perplexing the maritime industry is to comply with existing and soon-to-be-enacted regulations towards emissions reduction from shipping. This problem has been discussed in this study under three viewpoints: i) the marine engine efficiency, ii) the decision-making process for selecting the technologies for reducing air emissions from shipping and iii) the challenges in the ...
    • Typical hydrodynamic models for aquaculture nets: A comparative study under pure current conditions 

      Cheng, Hui; Li, Lin; Aarsæther, Karl Gunnar; Ong, Muk Chen (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-17)
      The net is regarded as the most critical component in marine aquaculture facilities as it is the only barrier which protects the environment from fish escapes. Accurate predictions of the net cage deformation and drag force on the nets are needed, both for ensuring fish welfare and for dimensioning of the mooring system. Thus, an appropriate hydrodynamic model is essential. In practice, two types ...
    • A dual linear autoencoder approach for vessel trajectory prediction using historical AIS data 

      Murray, Brian; Perera, Lokukaluge Prasad (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-21)
      Advances in artificial intelligence are driving the development of intelligent transportation systems, with the purpose of enhancing the safety and efficiency of such systems. One of the most important aspects of maritime safety is effective collision avoidance. In this study, a novel dual linear autoencoder approach is suggested to predict the future trajectory of a selected vessel. Such predictions ...
    • An AIS-Based Multiple Trajectory Prediction Approach for Collision Avoidance in Future Vessels 

      Murray, Brian; Perera, Lokukaluge Prasad (Peer reviewed; Bok; Chapter, 2019-11-11)
      This study presents a method to predict the future trajectory of a target vessel using historical AIS data. The purpose of such a prediction is to aid in collision avoidance in future vessels. The method presented in this study extracts all trajectories present in an initial cluster centered about a vessel position. Features for each trajectory are then generated using Principle Component Analysis ...
    • Evaluation of the water quality at Bogdalen watershed near Kvitfjell and Raudfjell wind farm area 

      Lu, Jinmei; Bui, Minh Tuan; Yuan, Fuqing (Journal article; Tidsskriftartikkel; Peer reviewed, 2019)
      Wind energy is one of the important renewable energies that get fast development in recent years. The development of wind turbines can have potential environmental impact on the surrounding environment. Especially when the wind turbines are built near the watersheds, water quality in the watershed may be degraded. In this study, the water quality in Bogdalen watershed that in or surrounding Kvitfjell ...
    • Non-contact sensing and modelling on the voltage and electric field for powered transmission line 

      Yuan, Fuqing; Lu, Jinmei (Journal article; Tidsskriftartikkel; Peer reviewed, 2020)
      From environmental, ecological or technical perspectives, the measurement of the potential voltage, electric field near the power transmission line is essential to ensure the exposure level does not exceed the limits of the government specified. This paper develops a potential voltage model, designs experiments to verify the developed model and to evaluate the parameters in the model. An electric ...
    • Decentralized System Intelligence in Data Driven Networks for Shipping Industrial Applications: Digital Models to Blockchain Technologies 

      Perera, Lokukaluge Prasad; Czachorowski, Karen Vanessa (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-10-14)
      Data driven networks applicable for shipping industrial applications to create decentralized system intelligence are considered in this study. Such system intelligence can facilitate to improve the respective operational efficiency in local (i.e. vessel operations) and global (i.e. logistics operations) scales in shipping as the main advantage. The main features of these data driven networks are ...
    • 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. ...
    • Investigation on heavy metals pollution of municipal refuse leachate from Tromsø landfill, Northern Norway 

      Fu, Shuai; Lu, Jinmei; Yuan, Fuqing (Journal article; Tidsskriftartikkel; Peer reviewed, 2019)
      To investigate the heavy metal pollution in leachate from sanitary landfill site of municipal solid waste, a survey was conducted in Tromsø, Northern Norway. Results shows that contents of heavy metals in landfill leachate follow the order Mn>Zn>Ni>Cu>Cr>As>Pb>Cd>Hg, and the order of the risk of different heavy metals is: Mn>Ni>As>Zn>Cr>Pb>Cd>Hg>Cu. The concentrations of Mn and Ni in landfill leachate ...
    • A Goal Programming Approach for a Fuzzy Single-Source Capacitated Facility Location Problem 

      Shojaeibarjouei, Abolfazl; Barabadi, Abbas; Tavakkoli-Moghaddam, Reza (Journal article; Tidsskriftartikkel; Peer reviewed, 2019)
      In this paper, we present a new mixed-integer linear goal programming (MILGP) model for a fuzzy single-source capacitated facility location problem (F-SSCFLP), in which demands are considered as triangular fuzzy values and capacity of facilities are fuzzy constraints. At first, the basic fuzzy model for the given problem is presented. Then, utilizing goal programming (GP) approach and fuzzy principals ...
    • Non-Preemptive Open Shop Scheduling Considering Machine Availability 

      Shojaeibarjouei, Abolfazl; Barabadi, Abbas; Tavakkoli-Moghaddam, Reza (Journal article; Tidsskriftartikkel; Peer reviewed, 2019)
      This paper considers a non-preemptive open shop scheduling problem (OSSP), in which machines are not available to process jobs on known periodic interval times resulted from periodic service repair, rest period, and so on. Asymmetric transportation time between machines is considered, which can be different from one job to another. The objective is to minimize the weighted mean completion time (WMCT). ...
    • Maritime Security and Threat Assessments 

      Eidnes, Ingrid Batalden; Batalden, Bjørn-Morten Erdal; Sydnes, Are K. (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-12)
      Maritime security is still a challenge in international trade. In this case‐study we analyze how the Norwegian Shipowners’ Mutual War Risks Insurance Association (DNK) provides Norwegian maritime companies with regional assessments of threat‐levels. Through a survey and a series of interviews, we study factors that affect the communication and perception of threats, in addition to how maritime ...
    • Risk assessment of wind farm development in ice proven area 

      Mustafa, Albara; Barabadi, Abbas; Markeset, Tore (Journal article; Tidsskriftartikkel; Peer reviewed, 2019)
      There many risks associated with wind farms operating in cold harsh areas, a number of these risks is caused by icing. Atmospheric and super-structure icing can cause ice accretion on wind turbines’ structure, and lead to public safety risks caused by ice throw and the failure of wind turbine’s components. Other risks can affect wind farm’s maintenance crew and their activities. Such risks are ...
    • Cyberspace Effects on Civil Society. The Ultimate Game-Changer or Not? 

      Montalvan Castilla, Johana Evelyn; Pursiainen, Christer Henrik (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-10-04)
      The article studies the effects of the emergence of cyberspace, or digitization, on civil society, and develops an analytical framework to that effect. It is distinguished between four types of civil societies: apolitical, political, transnational, and uncivic. Each type of civil society is considered separately vis-à-vis cyberspace developments in order to understand what kind of civil society is ...
    • Deep Learning towards Autonomous Ship Navigation and Possible COLREGs Failures 

      Perera, Lokukaluge Prasad (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-12-17)
      A structured technology framework to address navigation considerations, including collision avoidance, of autonomous ships is the focus of this study. That consists of adequate maritime technologies to achieve the required level of navigation integrity in ocean autonomy. Since decision-making facilities in future autonomous vessels can play an important role under ocean autonomy, these technologies ...
    • 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 ...
    • Temperature-driven variation in the removal of heavy metals from contaminated tailings leaching in northern Norway 

      Fu, Shuai; Lu, Jinmei (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-01-31)
      High amounts of tailings with a low recycling rate are generated during mining and smelting processes, and a lot of environmental problems were caused by heavy metal leaching from tailings. Temperature is a key point in heavy metals leaching, and knowing the effects of temperature on tailings leaching is useful for tailings management. A small-scale batch leaching experiment was conducted at different ...
    • Ship Performance and Navigation Information under High Dimensional Digital Models 

      Perera, Lokukaluge Prasad; Mo, Brage (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-04)
      Future vessels will be facilitated by modern internet of things to collect various ship performance and navigation information. Such information is collected as large-scale data sets, the so-called Big Data, that should be utilized towards digitalization of the shipping industry. However, various data handling challenges are encountered by the shipping industry during the phase of digitalization, ...