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norskFakultet for ingeniørvitenskap og teknologi: Recent submissions
Now showing items 21-40 of 1046
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Homogenization of nonlocal spectral problems
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-11)We consider a spectral problem for convolution-type operators in environments with locally periodic microstructure and study the asymptotic behavior of the bottom of the spectrum. We show that the bottom point of the spectrum converges as the microstructure period tends to zero, and identify the limit in terms of an additive eigenvalue problem for effective Hamilton–Jacobi equation. In the periodic ... -
A multi-objective approach for the integrated planning of drone and robot assisted truck operations in last-mile delivery
(Journal article; Tidsskriftartikkel; Peer reviewed, 2025-01-10)Supply chains are experiencing a major transition driven by changing customer expectations, environmental concerns, and technological development. Considering the surge in e-commerce since the pandemic, the path forward for affordable, responsive supply chains is autonomous last-mile delivery. Drone and robot technologies complement the last-mile delivery’s operational requirements and hence ... -
Fault Tolerant Flight Control for the Traction Phase of Pumping Airborne Wind Energy Systems
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-02)A fault-tolerant control approach is proposed, for a pumping airborne wind energy system (AWES) comprising a tethered fixed-wing aircraft with integrated propellers for vertical take-off and landing (VTOL). First, the flight control design for the traction phase of the system, when the tethered aircraft has to fly in loops using the rudder, is presented. Then, the presence of the propellers, that ... -
Large-Scale Reverse Pumping for Rigid-Wing Airborne Wind Energy Systems
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-25) -
Modelling ductile fracture in an Al alloy with crystal plasticity models
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-04-24)Crystal plasticity models enhanced with coupled or uncoupled damage and fracture criteria give an opportunity to account for the role of microstructure in ductile fracture, most directly representing the local variations of stress and strain fields inside and between the grains, voids and particles. Some computationally efficient crystal plasticity, damage and fracture models have recently been ... -
Frost durability of cementitious materials: What's next?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-23)Frost durability, a critical parameter for concrete, especially in harsh exposure regions, has been extensively researched, with almost four thousand papers published since the 1970s. However, a systematic mapping of this research is yet to be explored. This paper presents a novel approach based on Natural Language Processing (NLP) and machine learning to semi-automatically analyze the ... -
The representation of hydrogen in open-source capacity expansion models
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-12-19)The intermittent nature of wind and solar power has led to a scientific consensus in the international energy research community that a mix of energy sources and carriers is necessary to achieve carbon neutrality. The search for alternatives has sparked renewed interest in Hydrogen (H2) and its derivatives, such as ammonia and methane. It has also motivated researchers to expand their models to study ... -
The effect of oil shale ash and basalt-boron fiber on waste package gamma-radiation shielding properties
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-24)Oil shale ash is an abundant industrial residue that contains hydration products, which have been shown to immobilize heavy metals. The use of innovative additives such as oil shale ash (OSA) and basal-fiber materials containing boron (BBF) have not been thoroughly investigated. This study analyzes the potential of OSA-BBF concrete as an overpack material for low- and intermediate-level radioactive ... -
Research on wavelets and artificial intelligence algorithms for structural health monitoring of concrete bridges
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-02-23)In this paper, we present a comprehensive study of wavelet theory with a focus on structural damage detection. A new example of the application of operational modal analysis (OMA) techniques to a concrete railway arch bridge located over the Kalix river in L{\aa}ngforsen, Sweden is presented. Results from the OMA techniques are used for finite element model (FEM) updating of this concrete railway ... -
An algorithmic review of the technological progress and milestones in resource-constrained project planning
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-12-30)Engineering, procurement, and construction projects are time-intensive and subject to resource constraints. Modern project planning software requires optimization algorithms to schedule tasks while considering resource availability. A comprehensive review of the optimization algorithms used in project planning has not yet been conducted. This study seeks to bridge the gap through an algorithmic ... -
Educational Support for SMEs Transitioning from Industry 4.0 to Industry 5.0 - Insights and Lessons Learned from European Cooperation Projects
(Chapter; Bokkapittel, 2024-02-09)The ongoing transition from Industry 4.0 to Industry 5.0 brings promising prospects for small and medium-sized enterprises (SMEs) to bolster their competitiveness and sustainability. To fully capitalize the benefits brought by this transition, SMEs need to master the upskilling of their workforce that conforms to the rhythm of technological development. Creating an educational symbiosis which supports ... -
Towards the design of a smart warehouse management system for spare parts management in the oil and gas sector
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-25)Introduction: The oil and gas production industry requires rapid changing. As oil and gas companies around the world are called upon to decarbonize, several sectors within the industry are attempting to find new ways of working to achieve decarbonization. One of those sectors is spare parts warehousing. During the past decades of oil and gas production, spare parts warehousing has not been ... -
Marine winterization - Measures to abate sea-spray icing
(Doctoral thesis; Doktorgradsavhandling, 2024-12-20)<p>This thesis includes the topic of sea-spray icing on vessels and structures and dives further into methods of ice management. Sea-spray icing is a challenge in cold waters, particularly for small and mid-sized vessels. Excessive ice accretion is hazardous for vessel stability, operations and personnel safety. <p>Sea-spray icing from wave-vessel-wind interaction is a complex phenomenon. No measuring ... -
Ship appointment scheduling for lockage operations of waterway transport with non-punctual arrivals
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-25)The appointment scheduling of ships has been considered as an essential avenue for managing ship arrival pattern and mitigating waterway traffic congestion. This paper studies the ship appointment scheduling problem for lockage operations of waterway transport, and a new mathematical model is formulated to minimize the average waiting time of ships around the dam, in which the non-punctual arrival ... -
Exploring the development trajectory of single-machine production scheduling
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-25)The Single-Machine Scheduling Problem (SMSP) serves as the cornerstone of scheduling theory. Almost all developments in production planning and control were initially introduced and tested within single-machine production settings. Exploring the literature on SMSPs illuminates the entire development trajectory of scheduling theory. This study employs the Main Path Analysis (MPA) for a systematic ... -
An experimental study of effect of printed thickness on the mechanical properties of LPBF produced AlSi10Mg
(Chapter; Bokkapittel, 2024-04-24)Additive manufacturing process allows fabrication of parts with a broad range of sizes with high resolution. This size variation introduces new mechanical properties within the printed component, which creates a significant challenge for the qualification of additively manufactured parts. This unresolved issue hinders the implementation of additive manufacturing in high performance engineering ... -
Experimental Investigation of Free Space Optical Channel Performance in the Arctic Weather
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-07)This paper investigates the technical aspects of the 1550 nm free space optical (FSO) link in extreme Arctic weather, specifically in falling snow, which is currently understudied. We measured the time variation of the received optical power in many snowfall events and derived attenuation statistics. Continuous measurements allowed us to estimate attenuation under varying temperatures and humidity ... -
Multimodal analysis of saddle micro-terrain prone to wind disasters on overhead transmission lines
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-01-13)Pervasive micro-terrain is a significant contributor to wind disasters on transmission lines. This study explores the effect of saddle micro-terrain on the wind field of transmission lines and proposes relevant models and analysis methods. Firstly, the characteristic elements and parameters of saddle micro-terrain are extracted using DEM and established representative cross-sections for classification. ... -
Atmospheric icing meteorological parameter study using field experiments and simulation
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-12)Atmospheric icing on ground structures is a concern from design, operation, and safety perspectives. Supercooled water droplets size and liquid water content (LWC) are important weather parameters to better understand the ice accretion physics on ground structures. Most existing studies are based on measurements at high altitude. The study is based on the field results of a specific event (from ... -
A Decision Support Framework for Metal Additive Manufacturing Adoption in Small and Medium-Sized Enterprises
(Doctoral thesis; Doktorgradsavhandling, 2024-12-03)Today's manufacturing landscape is undergoing constant changes, particularly through the widespread integration of advanced digital technologies. Among these, Metal Additive Manufacturing (MAM) stands out, signaling a new era of flexibility and customization capabilities that promise to significantly enhance business competitiveness, sustainability, and cost efficiency. However, the outcomes of MAM ...
