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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 ...
(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 ...
(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 ...
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, 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 / 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 / PublishedVersion; Peer reviewed, 2017)
Ultraviolet (UV) SO2 cameras have become a common tool to measure and monitor SO2 emission rates, mostly from volcanoes but also from anthropogenic sources (e.g., power plants or ships). Over the past decade, the analysis ...
(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 / 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 / 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, 2017)
In this paper we present a novel method for measuring temperature dependent lifetime images with high spatial resolution using photoconductance calibrated photoluminescence (PL) imaging. In order to achieve this, PL images ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)
Results for (La,Mg)Ni3.5 and (La,Mg)(Ni,Al)3.5 systems synthesized by metallurgical and mechanochemical techniques are reported. Powder X-ray and neutron diffraction combined with Rietveld refinements and profile analysis ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)
The higher order multipoles above the electric quadrupole are commonly neglected in metamaterial homogenization. We show that they nevertheless can be significant when the second-order spatial dispersive effects, such as ...
(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2018)
Energy usage in LTE base stations are driven by spectral efficiency and traffic. To predict the energy usage these parameters must be forecasted. In this work we analyse hourly measurements collected from more than 12000 ...
(Doctoral thesis / Doktoravhandling, 2019)
High-speed flows through dense particle clouds occur in many technological applications such as explosion mitigation systems, combustion engines, drug-delivery systems, as well as natural phenomena such as volcanic eruptions ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)
It is well known that the usual Kramers–Kronig relations for the relative permeability function μ(ω) are not compatible with diamagnetism (μ(0) < 1) and a positive imaginary part (Im μ(ω) > 0 for ω > 0). We demonstrate ...
(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 / PublishedVersion; Peer reviewed, 2019)
Energy density and safety are the main factors that govern the development of the rechargeable battery technology. Currently, batteries beyond typical Li-ion batteries such as those based on solid-state electrolytes (SSEs) ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
We investigate the shock-induced flow through random particle arrays using particle-resolved Large Eddy Simulations for different incident shock wave Mach numbers, particle volume fractions and particle sizes. We analyze ...
(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)
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, 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 / 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 / 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, ...
(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, 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. ...
(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 ...
(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, 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, 2004)
(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 / 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 / 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 / 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 / PublishedVersion; Peer reviewed, 2020)
With the proliferation of technologies such as wireless sensor networks (WSNs) and the Internet of things (IoT), we are moving towards the era of automation without any human intervention. Sensors are the principal components ...
(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2020)
Non-orthogonal multiple access (NOMA) is consid-ered an important candidate for the next-generation cellular networks to address the issue of exponentially growing data traffic from technologies like the Internet of Things ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2020)
Securing and managing large, complex enterprise network infrastructure requires capturing and analyzing network traffic traces in real-time. An accurate passive Operating System (OS) fingerprinting plays a critical role ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
In this paper, we propose a novel parameter initial value estimation method of Lithium-ion battery for state of charge (SOC) estimation by using Local Regression Modeling (LRM) and Vector Fitting (VF). To estimate SOC ...
(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, 2021)
Due to the fast growth in global installed photovoltaic (PV) capacity, performance monitoring for large-scale PV systems is an increasingly relevant and important topic. A large volume of research exists in this field, but ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
We state and compare four different definitions of magnetic permeability for periodic, artificial media, or metamaterials. The connections among them, and properties in general, are discussed in detail, including causality, ...
(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 / PublishedVersion; Peer reviewed, 2020)
As the policies of a software-defined networking (SDN) network can be updateddynamically and often at a high pace, conflicts between policies can easily occur. Dueto the large number of switches and heterogeneous policies ...
(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 ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
Black TiO2 has emerged as one of the most promising photocatalysts recently discovered. The reason behind its catalytic activity is considered to be due to the presence of defects and Ti3+ species at the surface of black ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
During recent years, ray tracing has frequently been used to study the absorption characteristics of structured solar cells. However, wave properties such as absorption enhancement due to resonances in optically thin solar ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
The electricity grid is an important critical infrastructure that is undergoing major changes, due to the Internet of Things (IoT) and renewable energy, heading towards the smart grid. However, besides the many good promises ...
(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2019)
Over the past few years, innovation in the development of Wireless Sensor Networks (WSNs) has evolved rapidly. WSNs are being used in many application fields such as target coverage, battlefield surveillance, home security, ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
We report preferential orientation control in photochromic gadolinium oxyhydride (GdHO) thin films deposited by a two-step process. Gadolinium hydride (GdH2-x) films were grown by reactive magnetron sputtering, followed ...
(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 ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
In this paper the small-amplitude motion of multiple superposed viscous fluids is studied as a linearized initial-value problem. The analysis results in a closed set of equations for the Laplace transformed amplitudes of ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
Owing to the exponential proliferation of the Internet of Things (IoT), it is anticipated that the number of small IoT devices will grow expeditiously over the next few years. These billions of small IoT sensor and devices ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
The aim of this work is characterizing the class of LPV systems that admit steady-state trajectories depending exclusively on the scheduling parameter. In particular, it will be shown that only certain parameter dependent ...
(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 / 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 ...
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, 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 ...
(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)
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)
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 / AcceptedVersion; Peer reviewed, 2018)
A complete chemical and morphological analysis of the evolution of battery electrode materials can be achieved combining different and complementary techniques. Operando small-angle X-ray scattering (SAXS) and wide-angle ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
Abstract
The Radar Imager for Mars’ Subsurface Experiment (RIMFAX) is a Ground Penetrating Radar on the Mars 2020 mission’s Perseverance rover, which is planned to land near a deltaic landform in Jezero crater. RIMFAX ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
This paper proposes a linear parameter varying (LPV) interval unknown input observer for the robust fault diagnosis of actuator faults and ice accretion in unmanned aerial vehicles (UAVs) described by an uncertain model. ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
Artificial intelligence (AI) receives attention in media as well as in academe and business. In media coverage and reporting, AI is predominantly described in contrasted terms, either as the ultimate solution to all human ...
(Conference object / Konferansebidrag / PublishedVersion, 2018)
The aim of this work is to develop and test new methods for quality control of data from commercial monitoring systems for small and medium sized PV installations. Such installations often have limited or non-existent ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
Background: The increasing prevalence of gestational diabetes mellitus (GDM) among women of different ethnic backgrounds provides new challenges for health care professionals, who often find it difficult to provide information ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2020)
The coldest and densest structures of gas and dust in the Universe have unique spectral signatures across the (sub-)millimetre bands (υ ≈30 - 950 GHz). The current generation of single dish facilities has given a glimpse ...
(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, 2020)
Policy anomalies are frequent in nowadays’s computer networks due to their increasing configuration complexity. Resolving policy anomalies usually requires network administrator intervention, which is a time-intensive and ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
With the emergence of Internet of Things (IoT), securing and managing large, complex enterprise network infrastructure requires capturing and analyzing network traffic traces in real time. An accurate passive operating ...
(Master thesis / Masteroppgave, 2022)
(Doctoral thesis / Doktoravhandling, 2021)
The ground beneath our feet is anything but dry; there is more water held in Earth’s rocks than all the world’s oceans combined. Fluids in the subsurface are always on the move and understanding this is important in the ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
Determining subsurface properties through ground penetrating radar sounding can be challenging, especially in planetary exploration, where little is known about the terrain and additional observations are limited. Analysis ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2020)
Program evolution may reveal bad design decisions, misunderstandings, erroneous code, or erroneous specifications, because problems made early in the design of a system may not be discovered until much later in the life-time ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
The radiometric performance of cameras is customarily characterized and specified in terms of component properties such as F-number and readout noise. This paper considers the camera as an integrated unit and derives ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
Multi-function swarms are swarms that solve multiple tasks at once. For example, a quadcopter swarm could be tasked with exploring an area of interest while simultaneously functioning as ad-hoc relays. With this type of ...
(Master thesis / Masteroppgave, 2022)
Norwegian electricty demand toward 2050 Restricted Access
(Master thesis / Masteroppgave, 2022)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
As cost reductions have made photovoltaics (PV) a favorable choice also in colder climates, the number of PV plants in regions with snowfalls is increasing rapidly. Snow coverage on the PV modules will lead to significant ...
(Master thesis / Masteroppgave, 2021)
The healthcare centers at rural areas will have a lack of available sonographers who can perform ultrasound examinations on patients. To solve this issue and allow the patient to receive the necessary help, it is beneficial ...
(Master thesis / Masteroppgave, 2021)
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
The concept of digital literacy has been defined in numerous ways over the last two decades to incorporate rapid technological changes, its versatility, and to bridge the global digital divide. Most approaches have been ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
The disposal of unexploded ordnance (UXOs) at sea is a global problem. The mapping and remediation of historic UXOs can be assisted by autonomous underwater vehicles (AUVs) carrying sensor payloads such as synthetic aperture ...
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
This paper is concerned with stability and control of the parabolic p-Laplace equation. The autonomous equation is shown to be asymptotically stable, while the stronger property of exponential stability is guaranteed by ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
In this letter, a new method of path planning for unmanned ground vehicles (UGVs) on terrain is developed. For UGVs moving on terrain, path traversability and collision avoidance are important factors. If traversability ...
(Master thesis / Masteroppgave, 2021)
(Master thesis / Masteroppgave, 2022)
(Master thesis / Masteroppgave, 2021)
(Master thesis / Masteroppgave, 2022)
(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2021)
In this paper, a bidirectional relaying (BR) non-orthogonal multiple access (NOMA) with simultaneous wireless information and power transfer (SWIPT) termed as BR NOMA-SWIPT is proposed and investigated for the Internet of ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2023)
We propose and investigate a bidirectional device-to-device (D2D) transmission scheme that exploits cooperative downlink non-orthogonal multiple access (NOMA) (termed as BCD-NOMA). In BCD-NOMA, two source nodes communicate ...
(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
The growing number of data centers consumes a vast amount of energy for processing. There is a desire to reduce the environmental footprint of the IT industry, and one way to achieve this is to use renewable energy sources. ...