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PEM Fuel Cell Stack and System Modeling Restricted Access
(Master thesis / Masteroppgave, 2023)
Brenselceller basert på ren hydrogen er en viktig nøkkelteknologi for overgangen til et lav- og nullutslippssamfunn. Teknologien er allsidig og kan brukes både for storskala stasjonære og tung transport applikasjoner. For ...
(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2020)
Wi-Fi will be the preferred access network in smart infrastructure, which is a considerably cheaper alternative of mobile broadband. Emerging services such as Internet of things (IoT), virtual reality (VR) and ehealth, ...
(Master thesis / Masteroppgave, 2022)
(Doctoral thesis / Doktoravhandling, 2020)
Understanding the dynamic complexity of the internal states of TCP is a fundamental challenge, and particularly demanding due to the dynamics and complexity of modern networks. TCP is one of the key transport protocols of ...
(Master thesis / Masteroppgave, 2023)
Abstract: This thesis presents a sampling scheme for traversability mapping and a motion planning approach for terrain scenarios. The sampling scheme uses overlapping minimum enclosing cylinders to analyze a point cloud ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2020)
Reliable monitoring of PV systems is essential to establish efficient maintenance routines that minimize the levelized cost of electricity. The existing solutions for affordable monitoring of commercial PV systems are ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)
KBaPO4 – recently reported to hydrate in steam at 80°C into a novel low-temperature protonic conductor – was synthesized by a solid state reaction and its electrical properties characterized by impedance spectroscopy. At ...
(Doctoral thesis / Doktoravhandling, 2023)
Radar echoes on Mars can reveal stories about our neighbour planet’s hidden past. The RIMFAX ground-penetrating radar on NASA’s Mars 2020 Perseverance rover mission, was the first to conduct soundings while driving over ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
Amidst the rapid development of the fifth generation (5G) networks, Internet of Things (IoT) is considered as one of the most important part of 5G next generation networks as it can support massive object communications. ...
Intersecting near-optimal spaces: European power systems with more resilience to weather variability
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2023)
We suggest a new methodology for designing robust energy systems. For this, we investigate so-called near-optimal solutions to energy system optimisation models; solutions whose objective values deviate only marginally ...
(Doctoral thesis / Doktoravhandling, 2021)
Humanity through centuries of evolution has become the dominant species on the planet. We enjoy comforts enabled by our advancements in Information and Communications Technology (ICT). But all this is threatened by population ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
Metal hydrides are known as a potential efficient, low-risk option for high-density hydrogen storage since the late 1970s. In this paper, the present status and the future perspectives of the use of metal hydrides for ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
Models of quantum systems on curved space-times lack sufficient experimental verification. Some speculative theories suggest that quantum correlations, such as entanglement, may exhibit different behavior to purely classical ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)
Small-angle neutron scattering combined with powder neutron diffraction was employed to study the phase formation upon absorption/desorption of hydrogen gas in Li- and Na-intercalated fullerides. The comparative system ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
Background
Intimate partner violence (IPV) around the time of pregnancy is a recognized global health problem with damaging consequences. However, little is known about the effect of violence assessment and ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
This paper is a collection of selected contributions of the 1st International Workshop on Mechanochemistry of Metal Hydrides that was held in Oslo in May 2018. In this paper, the recent developments in the use of ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
This paper investigates the problem of robust tracking control for quasilinear reaction–diffusion partial differential equations subject to external unknown perturbations. The considered class of equations is quite general, ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)
We investigated using terrain referenced navigation in shallow water in the presence of unknown tide, with an autonomous underwater vehicle equipped with a high resolution bathymetric sensor. The mission area had both ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)
The single-photon detectionefficiency of the detector unit is crucial for the security of common quantum key distribution protocols like Bennett-Brassard 1984 (BB84). A low value for the efficiency indicates a possible ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)
Conventional textbook treatments on electromagnetic wave propagation consider the induced charge and current densities as “bound” and therefore absorb them into a refractive index. In principle, it must also be possible ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
We present a method for extracting local recombination rates from photoluminescence images of double side passivated wafers, using simulations of lateral charge carrier diffusion in two dimensions. By fitting the simulated ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
The Digital Divide is one of the key challenges for mankind. Despite attempts to digitally include people, the divide is bigger than ever. This contribution [1] to a sustainable future promotes “Internet lite” as the new ...
(Doctoral thesis / Doktoravhandling, 2024)
Hydrogen produced with renewable energy, also known as green hydrogen, could be a piece of the puzzle to reduce emissions of CO2 and other greenhouse gases from human activities. However, the production of green hydrogen ...
(Chapter / Bokkapittel / SubmittedVersion, 2019)
The growing number of Wi-Fi networks at homes, buildings and public areas can consume excessive energy and therefore increase CO2 emissions. Hence, the aim of this paper is to investigate the energy consumption of Wi-Fi ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
There is a profound duality between rays and waves. In fact, 70 years ago, in the context of quantum mechanics, Feynman showed that rays, properly equipped with phases and correctly summed, provide exact solutions of the ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
Semiconductor nanocrystals are often proposed as a viable route to improve solar energy conversion in photovoltaics and photoelectrochemical systems. Embedding the nanocrystals in, e.g. a transparent and conducting electrode ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
The photogenerated current of solar cells can be enhanced by light management with surface structures. For solar cells with optically thin absorbing layers, it is especially important to take advantage of this fact through ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
Magnetic permeabilities derived for infinite, periodic media are used in the Fresnel equation to calculate the reflection from corresponding semi-infinite media. By comparison to finite-difference time-domain (FDTD) ...
(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2019)
There is an expected growth in underwater acoustic data traffic. To meet the demand of high data throughput, a migration towards the very high frequency band (>100 kHz) will be necessary. The increment in frequency comes ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2004)
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2020)
Recent long term planning studies have demonstrated the important role of variable renewables (VRE) in decarbonising our energy system. However, cost-optimising models do not capture the visual impact of VREs on the landscape ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
This study investigates how thermal signatures observed in PV systems using infrared thermography (IRT) affect the performance of PV modules and strings. To assess this, we use IRT images as a basis for circuit modeling ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
The present work was focused on the studies of the effect of variation of stoichiometric composition of Ti–Zr based AB2±x Laves phase alloys by changing the ratio between A (Ti + Zr) and B (Mn + V + Fe + Ni) components ...
(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2019)
The Round-Trip Time (RTT) is a property of the path between a sender and a receiver communicating with Transmission Control Protocol (TCP) over an IP network and over the public Internet. The end-to-end RTT value influences ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
In future smart transmission grids, there are distributed applications that will benefit from the deployment of Internet Protocol (IP) multicast technology for communication. Sharing of Routable-Sample Values (R-SV) and ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)
Software Defined Networking (SDN) is designed for dynamic policy update where frequent changes are pushed to the forwarding devices. Different offline approaches for detecting misconfiguration anomalies in SDN by taking a ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
The emission band of holmium-doped silica fibers extends beyond 2200 nm, which means these lasers have the potential of covering considerable parts of the atmospheric transmission window between ∼2100 nm and 2250 nm. ...
(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2019)
A novel approach to calculating TNT equivalencies and safety distances for explosives, using a combination of thermochemical computations and computational fluid dynamics, is presented. This enables the estimation of safety ...
(Master thesis / Masteroppgave, 2021)
One of the methods to compress hydrogen gas is through the utilization of thermal metal hydride hydrogen compressors (TMHHCs) The present work aims to investigate the structural and thermodynamic properties of the Ti1.1CrMn ...
(Master thesis / Masteroppgave, 2021)
It is of great interest in an increasing number of fields and applications to use autonomous vehicles in varying and challenging terrain conditions. In these conditions, the vehicle's movement is strongly affected by the ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
In recent years, it has come to attention that governments have been doing mass surveillance of personal communications without the consent of the citizens. As a consequence of these revelations, developers have begun ...
(Master thesis / Masteroppgave, 2021)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
The dynamic range of a hyperspectral camera can have a strong impact on the quality and integrity of the collected spectra. For the image sensor chip alone, the dynamic range is the ratio between the saturation level and ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
There is a need for tool support for structured planning, execution and analysis of simulation-based training for crisis response and management. As a central component of an architecture for such tool support, we outline ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
A comparative study of the effect of melt spinning on the electrochemical properties of the C14 and C15 AB2 alloys has been performed. The wheel speeds of 630, 2100, and 4100 cm/s were applied during the rapid solidification ...
(Master thesis / Masteroppgave, 2021)
This thesis will focus on developing a Digital Twin prototype for an autonomous vehicle. The goal for the project was to discover how OpenModelica and Carla can be connected and configured to serve as a Digital Twin. It ...
Proton Exchange Membrane Water Electrolyzer Modeling Restricted Access
(Master thesis / Masteroppgave, 2021)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Enhancing the energy output of solar cells increases their competitiveness as a source of energy. Producing thinner solar cells is attractive, but a thin absorbing layer demands excellent light management in order to keep ...
(Chapter / Bokkapittel / PublishedVersion; Peer reviewed, 2018)
This paper describes the current state of our work towards a multi-function swarm of UAVs that adapts to user preferences. To achieve this, we employ software simulation and an evolutionary search method for offline ...
(Master thesis / Masteroppgave, 2021)
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
Schematic drawings showing railway tracks and equipment are commonly used to visualize railway operations and to communicate system specifications and construction blueprints. Recent advances in on-line collaboration and ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
We introduce Dynamic Structural Operational Semantics (DSOS or Dynamic SOS) as a framework for describing semantics of programming languages that include dynamic software upgrades, i.e., for upgrading software code during ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
Methods for quick and accurate detection and diagnosis of defects in PV systems are increasingly important as the global photovoltaic (PV) capacity continues to grow at a rapid pace. Two of the most used methods for defect ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
We propose a method for jointly estimating intrinsic calibration and internal clock synchronisation for a pantilt- zoom (PTZ) camera using only data that can be acquired in the field during normal operation. Results show ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
Fresnel's equations describe the reflection and transmission of electromagnetic waves at an interface between two media. It turns out that these equations can be used in quasistatics and even statics, for example to ...
Building Confidence using Beliefs and Arguments in Security Class Evaluations for IoT (long version)
(Research report / Forskningsrapport, 2020)
We have previously proposed a security classification methodology for IoT systems and have applied it to the smart grid and smart home domain. This method departs from classical risk analysis and certification methods in ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
In this paper, we report the microstructure and first hydrogenation properties of TiFe cast with 4 wt.% of Zr. Measurements were made in as-cast state and after processing by ball milling and cryomilling. It was found that ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Water photoelectrolysis has the potential to produce renewable hydrogen fuel, therefore addressing the intermittent nature of sunlight. Herein, a monolithic, photovoltaic (PV)-assisted water electrolysis device of minimal ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
This study investigates the Reynolds-number dependence of shock-induced flow through stationary particle clouds at 10% volume fraction, using ensemble-averaged results from three-dimensional particle-resolved large eddy ...
(Master thesis / Masteroppgave, 2022)
Formations are seen in nature as means of effective transportation. Humans have used formations in formation flying, military formations, and sports such as football. Formation control is an expansive field that has seen ...
Using Machine Learning to generate Virtual Avatars Restricted Access
(Master thesis / Masteroppgave, 2021)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Large PV plants are increasingly common in locations with colder climates where snow can lead to significant PV power loss. For these locations, estimates of snow loss is necessary for accurate PV yield modeling. Robust ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
To achieve accurate PV energy yield assessments for cold climate locations where snowfalls can lead to significant power losses in the wintertime, improvement and validation of snow loss modeling is necessary. In this paper ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
Indoor positioning systems are crucial to provide location based services in areas that are not covered by a Global Navigation Satellite System. Among the many technologies applied to this field, ultrasound has emerged as ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
This article assesses how the ground-penetrating radar RIMFAX will image the crater floor at the Mars 2020 landing site, where lithological compositions and stratigraphic relationships are under discussion prior to mission ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
We present a holmium-doped all-fiber master oscillator power amplifier (MOPA) system operating at 2108 nm targeting optical frequency conversion applications. The MOPA delivers pulses of 0.52 mJ energy at 10 kHz repetition ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
The availability of inertial navigation sensors in smartphones has facilitated the development of pedestrian dead reckoning (PDR) models on a large scale. These models often consist of a step detection algorithm combined ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Background
Health workers have traditionally delivered health promotion and education to rural communities in the Global South in paper leaflet formats or orally. With the rise of digital technologies, health ...
Hydrogen from offshore wind - The role of life cycle assessment in the optimal infrastructure design
(Master thesis / Masteroppgave, 2022)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
To reduce costs, the solar cell industry aims at producing thinner solar cells. Structuring the surfaces of optically thin devices is important for avoiding transmission-related losses and, hence, increasing their efficiency. ...
(Doctoral thesis / Doktoravhandling, 2024)
Astronomers, early proponents of climate change science since the 1970s, currently seek to shift their observatories and related infrastructure to renewable energy sources to address global warming. Due to their remote ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Video conferencing services based on web real-time communication (WebRTC) protocol are growing in popularity among Internet users as multi-platform solutions enabling interactive communication from anywhere, especially ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Single-photon pulses cannot be generated on demand, due to incompatible requirements of positive frequencies and positive times. Resulting states therefore contain small probabilities for multiphotons. We derive upper and ...
(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2020)
The proliferation of IoT (Internet of Things) though making life easier, comes with security and privacy challenges. We have previously proposed a security classification methodology meant to help in practice build IoT ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Video on demand (VoD) services such as YouTube have generated considerable volumes of Internet traffic in homes and buildings in recent years. While Internet service providers deploy fiber and recent wireless technologies ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
Although the group delay of classical pulses through a barrier may suggest superluminality, the information transfer is limited by the precursor, which propagates at the vacuum light speed. Single photons, however, have ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
This paper introduces and validates a real-time dynamic predictive model based on a neural network approach for soft continuum manipulators. The presented model provides a real-time prediction framework using neural-network-based ...
(Journal article / Tidsskriftartikkel / SubmittedVersion, 2022)
We develop a logic-based approach for designing simulation-based training scenarios. Our methodology embodies a concise definition of the scenario concept and integrates the notions of training goals, acceptable versus ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
Concepts such as Industry 4.0 and Cyber-Physical Systems may bring forward a new industrial revolution. These concepts require extensive connectivity far beyond what is provided by traditional industrial networks. The ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
Inertial navigation of pedestrians carrying a smart device is a core component of many indoor positioning systems. While infrastructure-based solutions typically depend on an installation of dedicated hardware, inertial ...
GPS timing interference - Building a setup for evaluating the effect of jamming and spoofing on GPS based timing devices Restricted Access
(Master thesis / Masteroppgave, 2021)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Troubleshooting in SDN-based networks is still a cumbersome task that can overwhelm human attention. Various anomalies, such as installation failure, disordered rules, and loops, remain unnoticed even when the most recent ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Human personality plays a crucial role in decision-making and it has paramount importance when individuals negotiate with each other to reach a common group decision. Such situations are conceivable, for instance, when a ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
In group decision-making (GDM), fuzzy preference relations (FPRs) refer to pairwise preferences in the form of a matrix. Within the field of GDM, the problem of estimating missing values is of utmost importance, since many ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Abstract
The development of efficient storage systems is one of the keys to the success of the energy transition. There are many ways to store energy, but among them, electrochemical storage is particularly ...
(Master thesis / Masteroppgave, 2022)
Platooning is when one or more follower vehicles follow a lead vehicle autonomously based on information gained through sensors or communication. Due to being autonomous, the vehicles in the platoon can react faster and ...
(Doctoral thesis / Doktoravhandling, 2022)
In order to address the environmental challenges we face, transitioning towards sustainable, low emission energy systems is of paramount importance. Solar photovoltaics (PV) is a technology that plays an important role in ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Multispectral imaging is an attractive sensing modality for small unmanned aerial vehicles (UAVs) in numerous military and civilian applications such as reconnaissance, target detection, and precision agriculture. Cameras ...
(Master thesis / Masteroppgave, 2022)
(Master thesis / Masteroppgave, 2022)
In order to further the sustainability of renewable energy generation, the way land use is allocated must be considered. In the case of solar energy, land that is best used for photovoltaic power plants is often also best ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Traversal in off-road conditions for Unmanned Ground Vehicles is highly relevant for defence applications, with an increasing amount of research being put into the field. A central part of the autonomous traversal is path ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Empirical studies examining the interplay between informal and formal institutions on economic growth are scarce. As a result, we do not know how differences in trust affect the economic returns of the quality of regional ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Abstract
Industrial and public interest in hydrogen technologies has risen strongly recently, as hydrogen is the ideal means for medium to long term energy storage, transport and usage in combination with renewable ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
This paper presents the design, control, and experimental evaluation of a novel fully automated robotic-assisted system for the positioning and insertion of a commercial full core biopsy instrument under guidance by ...
(Master thesis / Masteroppgave, 2022)
Formålet med dette prosjektet er å undersøke potensialet for elektrisitetsproduksjon med bifacial solcelle (PV) systemer på nordlige breddegrader. Prosjektet undersøker hvordan ytelsen til et bifacial PV-system avhenger ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
The high spatial and temporal resolution electricity system model, highRES, is used to design cost-effective, flexible and weather resilient electricity systems for Great Britain and Europe. The model is specifically ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2023)
Energy systems optimisation models are used for analysing energy systems and questions of e.g. greenhouse gas mitigation aligned with the Paris Agreement. However, the techno-economic nature of energy system models has ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
The Mjølnir impact crater in the Norwegian Barents Sea features among the 20 largest impact craters listed in the Earth Impact Database. The impact is dated to 142 ± 2.6 Ma, corresponding closely to the Jurassic/Cretaceous ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
To improve the security and reliability of wind energy production, short-term forecasting has become of utmost importance. This study focuses on multi-step spatio-temporal wind speed forecasting for the Norwegian continental ...