Browsing Articles by Title
Now showing items 687-706 of 842
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Solar Wind from Coronal Funnels and Transition Region Lyalpha
(2005)Using a newly developed gyrotropic solar wind model that extends continuously from the mid-chromosphere to 1 AU and that accounts for radiative losses in the transition region, we have studied the difference between the ... -
Solving non-linear Boolean equation systems by variable elimination
(2019-08-17)In this paper we study Boolean equation systems, and how to eliminate variables from them while bounding the degree of polynomials produced. A procedure for variable elimination is introduced, and we relate the techniques ... -
Sonar scattering from the sea bottom near the Norwegian coast
(2017)High false alarm rates on active sonar systems in shallow waters is a well known problem which may be a limiting factor for the sonar performance. One way to reduce the false alarm rate is through supervised learning and ... -
Source Localization With Multiple Hydrophone Arrays via Matched-Field Processing
(2016)This paper considers approaches to combining information from multiple arrays in matched-field processing (MFP) for underwater acoustic source localization. The standard approach is to apply conventional MFP for each array ... -
The Space of Influence: Developing a New Method to Conceptualise Foreign Information Manipulation and Interference on Social Media
(2023-05)Foreign information manipulation and interference (FIMI) on social media is a fast- evolving threat to democracies. However, there is a growing need to systematically conceptualise the phenomenon. General Morphological ... -
Spaceborne Bistatic SAR Processing Using the EETF4 Algorithm
(2009)In this letter, the fourth-order extended exact transfer function (EETF4) is adapted for spaceborne bistatic synthetic aperture radar (SAR) processing. The problems with high squint and large bistatic Doppler centroid ... -
Sparse Phase Estimation and Processing of Independent Coherent Processing Intervals
(2017)Radars employing electronically steering arrays are capable of instantaneously altering the direction of the beam along with other parameters. This flexibility offers great opportunities to a radar as it may e.g. divide ... -
Sparse range-Doppler image construction with neural networks
(2020-06-11)The principles outlined by compressed sensing can permit a sensor to collect reduced amount of data and still reconstruct an exact outcome. This can for example be used to generate super-resolution sparse range-Doppler ... -
Spatial coherence of speckle for repeat-pass synthetic aperture sonar micronavigation
(2021-03-31)Accurate positioning of autonomous underwater vehicles is a major challenge. The long-term drift is problematic if global position updates are not available, and for applications such as repeat-pass interferometry and ... -
Spawning Atlantic cod (Gadus morhua L.) exposed to noise from seismic airguns do not abandon their spawning site
(2022-11-15)Seismic airgun surveys may disturb and displace fish at large ranges. If such displacement causes fish to abandon spawning grounds, reproductive success could be impacted. To investigate whether airgun sound causes cod ... -
Specifying radiometric performance of hyperspectral and conventional cameras: A minimal set of independent characteristics
(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 ... -
Spectral characteristics of moist birch leaves and synthetic materials: experimental studies and evaluation of models
(2021-11-09)The optical depth of biomaterials and natural backgrounds varies with their environment and incoming light properties. Deciduous trees, for instance, have canopy thicknesses that vary significantly from one place to another. ... -
Spectral properties of multilayered oak leaves and a camouflage net: experimental measurements and mathematical modelling
(2021-09-21)The development of state-of-the-art surveillance technology forces nations to develop camouflage with advanced capabilities. Owing to the abundance and wide distribution of leaves, their spectral properties are often ... -
Spectral reflectance and transmission properties of a multi-layered camouflage net: Comparison with natural birch leaves and mathematical models
(2020-09-20)With improved specifications and capabilities of modern sensors and detectors, concealment is an increasingly challenging endeavor. Concealment from modern sensors requires advanced camouflage material that can provide low ... -
Spectral reflectance measurements of snow and snow covered objects: experimental studies compared with mathematical models
(2021-09-12)In this study, we have investigated reflectance spectra of different snow types under various conditions. Snow reflectance is interesting from a camouflage point of view as snow covers large land areas in many parts of the ... -
Sperm whales reduce foraging effort during exposure to 1-2 kH z sonar and killer whale sounds
(2016)The time and energetic costs of behavioral responses to incidental and experimental sonar exposures, as well as control stimuli, were quantified using hidden state analysis of time series of acoustic and movement data ... -
Spin scan tomographic array-based imager
(2014)This work presents a novel imaging device based on tomographic reconstruction. Similar in certain aspects to the earlier presented tomographic scanning (TOSCA) principle, it provides several important enhancements. The ... -
Spin scan tomographic imager
(2015)A novel imaging device based on tomographic reconstruction is presented. The imager is based on rotating an image of the scene onto a linear detector array, and then reconstructing a 2-dimensional image from the detector ... -
Spin-vibronic interaction induced reverse intersystem crossing: A case study with TXO-TPA and TXO-PhCz molecules
(2022-11-01)We highlight the important roles the direct spin–orbit (DSO) coupling, the spin-vibronic (SV) coupling, and the dielectric constant of the medium play on the reverse intersystem crossing (RISC) mechanism of TXO-TPA and ...