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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

The variations of atmospheric Δ14C over the past two millennia are classically attributed to changes in its production rate in the upper atmosphere, which in turn is related to changes in solar activity and the Earth's magnetic field. However, the potential contribution of atmospheric and oceanic circulation changes during this period has not been precisely quantified. This has been achieved here

Configuring reconfigurable intelligent surfaces (RISs) based on a practical RIS model is a fundamental problem in RIS-assisted wireless transmission. In this work, we propose a concept named optimal phasor (OP), a latent quantity that can considerably help the practical model-based RIS configuration. Under such a concept, we can design versatile algorithms that are applicable to different RIS mode

Uppenbarelseboken avtäcker med sina fasansfulla syner – sin Apokalyps – vad som ska ske på den yttersta dagen, då allt ont ska förgås och ett nytt rike ska upprättas. Men numera menas ofta med apokalyps enbart den skräckfyllda, mytologiska spådomen om en framtida katastrof. Kan man istället förstå Uppenbarelsebokens syner som en varning, för den katastrof vi själva är med om att skapa här och nu,

Extreme solar particle events (ESPEs) are infrequent yet highly potent manifestations of solar activity. These events result in the production of significant amounts of cosmogenic isotopes (CIs): 10Be, 36Cl, and 14C, which are subsequently deposited in natural stratified archives. Analyzing CI measurements from these archives allows us to assess the particle fluxes during ESPEs. In this study, we

Multi-archive studies of climate events and archive-specific response times require synchronous time scales. Aligning common variations in the cosmogenic radionuclide production rate via curve fitting methods provides a tool for the continuous synchronization of natural environmental archives down to decadal precision. Based on this approach, we synchronize 10Be records from Western Gotland Basin

The cluster power is an important parameter for cluster-based wireless channel models. This paper addresses modeling and estimation of the cluster power for wireless channels. A novel way of estimating the cluster decay and cluster fading, where the effects of the noise floor is taken into account, is presented. Due to the noise floor present in the measurement, only a limited number of clusters a

Product codes, due to their relatively large minimum distance, are often seen as a natural solution for applications requiring low error floors. In this paper, we show by means of an ensemble weight enumerator analysis that the minimum distance multiplicities of product codes are much higher than those obtainable by other generalized LDPC (GLDPC) constructions employing the same component codes. W

MacKay-Neal (MN) and Hsu-Anastasopoulos (HA) low-density parity-check (LDPC) codes are known to achieve the capacity of memoryless binary-input symmetric-output channels under maximum likelihood (ML) decoding with bounded col- umn and row weight in their associated parity-check matrices. Recently, Kasai and Sakaniwa showed that spatially coupled (SC) versions of the MN and HA LDPC codes have belie

This paper highlights the issues of detecting Java concurrency bugs using static code analysis tools. Concurrency bugs are often hard to find because of interleaving threads and there is need to use static analysis tools to detect the concurrency bugs. In the literature review, we established that there are number of static analysis tools such as FindBugs, JLint and Chord, used in experiments to d

This paper presents the hardware implementation of a wavelet based event detector for cardiac pacemakers. A high level energy estimation flow was applied to evaluate energy efficiency of standard-cell based designs, over several CMOS technology generations, from 180 to 65 nm, operated in the sub-threshold domain. The simulation results indicate a 65 nm low-leakage high-threshold (LL-HVT) CMOS tech

Bioaerosols include bacterial cells and spores, viruses, pollen, fungi, algae, detritus, allergens and cell fragments. Bioaerosol particles are usually a small fraction of all aerosol particles in our surroundings, but their impact can be critical. They are a means for transmission of disease, they cause allergic reactions and they have effects on the global climate, ecology and biodiversity. This

It has previously been shown that ensembles of terminated protograph-based low-density parity-check (LDPC) convolutional codes have a typical minimum distance that grows linearly with block length and that they are capable of achieving capacity approaching iterative decoding thresholds on the binary erasure channel (BEC). In this paper, we review a recent result that the dramatic threshold improve