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Understanding atmospheric response to radiative forcing, including the intensity and distribution of wind patterns is critical as this might have important implications in the coming decades. Long-term episodes of reduced solar activity (i.e. Grand Solar Minima, GSM) have triggered rapid climate change in the past, recorded in proxy-based records, including varved sediments from Meerfelder Maar, G
In this paper we study two major challenges in few-shot bioacoustic event detection: variable event lengths and false-positives. We use prototypical networks where the embedding function is trained using a multi-label sound event detection model instead of using episodic training as the proxy task on the provided training dataset. This is motivated by polyphonic sound events being present in the b
Vehicular networks allow for a variety of applications ranging from platooning to fully automated driving. Most of such applications require the vehicles that constitute the networks to be aware of their relative or absolute position as well as the position of nearby vehicles. To this end, multiple positioning methods can be employed, among such methods are Global Positioning Systems or methods th
In this paper, a novel three-dimensional (3D) massive multiple-input multiple-output (MIMO) millimeter wave (mmWave) geometry-based stochastic model (GBSM) is proposed for sixth-generation (6G) vehicle-to-vehicle (V2V) channels. In the proposed GBSM, clusters in the environment are divided into static clusters and dynamic clusters. Furthermore, the time-variant acceleration together with the integ
Lateglacial and Holocene summer sea-surface temperature (SST) variability in the northern North Atlantic was reconstructed based on diatom records from two sediment cores from the North Icelandic shelf. The temperature changes are discussed in relation to palaeoceanographic circulation patterns and past climatic changes. Modern diatom data from surface sediments from around Iceland and Southeast a
Major atmospheric oxidants (OH,O3 and NO3) dominate the atmospheric oxidation capacity, while H2SO4 is considered as a main driver for new particle formation. Although numerous studies have investigated the long-term trend of ozone in Europe, the trends of OH, NO3 and H2SO4 at specific sites are to a large extent unknown. The one-dimensional model SOSAA has been applied in several studies at the S
The incorporation of water isotopologues into the hydrology of general circulation models (GCMs) facilitates the comparison between modeled and measured proxy data in paleoclimate archives. However, the variability and drivers of measured and modeled water isotopologues, as well as the diversity of their representation in different models, are not well constrained. Improving our understanding of t
This article aims at providing insights for a comprehensive understanding of THz propagation channels. Specifically, we discuss essential THz channel characteristics to be well understood for the success of THz communications. The methodology of establishing realistic and 6G-compliant THz channel models based on measurements is then elaborated on, followed by a discussion on existing THz channel m
Factorization methods are frequently used for structure from motion problems (SfM). In the presence of noise they are able to jointly estimate camera matrices and scene points in overdetermined settings, without the need for accurate initial solutions. While the early formulations were restricted to affine models, recent approaches have been show to work with pinhole cameras by minimizing object s
Algebraic reasoning has proven to be one of the most effective approaches for verifying gate-level integer mul-tipliers, but it struggles with certain components, necessitating the complementary use of SAT solvers. For this reason validation certificates require proofs in two different formats. Approaches to unify the certificates are not scalable, meaning that the validation results can only be t
This paper proposes a belief propagation (BP)-based algorithm for sequential detection and estimation of multipath component (MPC) parameters based on radio signals. Under dynamic channel conditions with moving transmitter/receiver, the number of MPCs, the MPC dispersion parameters, and the number of false alarm contributions are unknown and time-varying. We develop a Bayesian model for sequential
The exact spatial and temporal behaviour of rapid climate shifts during the Last Glacial– Interglacial Transition are still not entirely understood. In order to investigate these events, it is necessary to have detailed palaeoenvironmental reconstructions at geographically spread study sites combined with reliable correlations between them. Tephrochronology, i.e., using volcanic ash deposits in ge
The strength of the geomagnetic field has decreased rapidly over the past two centuries, coinciding with an increasing field asymmetry due to the growth of the South Atlantic Anomaly. The underlying processes causing the decrease are debated, which has led to speculation that the field is about to reverse. Here, we present a geomagnetic field model based on indirect observations over the past 9,00
The recent COVID-19 pandemic highlighted the need of non-pharmaceutical interventions in the first stages of a pandemic. Among these, lockdown policies proved unavoidable yet extremely costly from an economic perspective. To better understand the tradeoffs between economic and epidemic costs of lockdown interventions, we here focus on a simple SIR epidemic model and study lockdowns as solutions to
Bakgrund och syfteProjektet har initierats för att kunna verifiera och påvisa värde av s.k. Mixed Reality och HoloLens inom sjukvården i Sverige samt den kliniska verksamheten.Det finns enstaka ställen i världen där HoloLens 2 används kliniskt. Region Skåne har identifierat möjligheten att HoloLens 2 kan understötta specialistinvolvering på akutmottagningen och möjlighet för specialistinvolvering
Cosmogenic radionuclide records (e.g., 10Be and 14C) contain information on past geomagnetic dipole moment and solar activity changes. Disentangling these signals is challenging, but can be achieved by using independent reconstructions of the geomagnetic dipole moment. Consequently, solar activity reconstructions are directly influenced by the dipole moment uncertainties. Alternatively, the known
In this paper we study structure from motion problems for 1D radial cameras. Under this model the projection of a 3D point is a line in the image plane going through the principal point, which makes the model invariant to radial distortion and changes in focal length. It can therefore effectively be applied to uncalibrated image collections without the need for explicit estimation of camera intrin
Galactic cosmic rays (GCRs) interact with the Earth’s atmosphere to produce energetic neutrons and cosmogenic radionuclides, such as 14C. The atmosphere is partially shielded from the interstellar GCR spectrum by both the geomagnetic and solar magnetic fields. Solar shielding is often expressed as the heliospheric modulation potential ϕ, which consolidates information about the strength and struct
10Be is produced by the interaction between galactic cosmic rays (GCRs) and solar energetic particles (SEPs) with the Earth's atmospheric constituents. The flux of GCRs is modulated by the varying strength of the magnetic fields of the Earth and the Sun. Measurement of 10Be concentrations from polar ice cores is thus a valuable tool to reconstruct the variations in the geomagnetic field and solar
In this paper, using tools from graph theory we provide verifiable necessary and sufficient conditions for the existence of a unique hydraulic equilibrium in district heating systems of meshed topology and containing multiple heat sources. Even though numerous publications have addressed the design of efficient algorithms for numerically finding hydraulic equilibria in the general context of water
