Filtyp
We deal with the important applicative problem of distributed cameras calibration. We model a network of N cameras as an undirected graph in which communicating cameras can measure their relative orientation in a noisy way. These measures can be used in order to minimize a suitable cost function. The shape of this cost function depends on a vector of integers K. We propose two algorithms which in
In this paper, we perform an iterative decoding threshold analysis of LDPC block code ensembles formed by terminating (J,K)-regular and irregular AR4JA-based LDPC convolutional codes. These ensembles have minimum distance growing linearly with block length and their thresholds approach the Shannon limit as the termination factor tends to infinity. Results are presented for various ensembles and te
Research on human emotions towards large carnivores is often based on self-reported emotions. This study aimed to investigate physiological and behavioral responses to feared animals among people who say that they are fearful or not fearful of brown bear and wolf. Participants were recruited to be bear fearful only (n=8), fearful of both bear and wolves (n=15), or fearful of neither carnivore (n=1
A new proof of the equivalence of the Taut String Algorithm and the one-dimensional Rudin–Osher–Fatemi model is presented. Based on duality and the projection theorem in Hilbert space, the proof is strictly elementary. Existence and uniqueness of solutions (in the continuous case) to both denoising models follow as by-products. The standard convergence properties of the denoised signal, as the reg
I syfte att utvärdera effekten av dubbdäcksförbudet på Friggagatan med avseende på luftkvaliteten har Miljöförvaltningen i Göteborg på uppdrag av trafikkontoret i Göteborg utfört luftkvalitetsmätningar på Friggagatan mellan 2013-01-01 och 2013-09-30. Dessutom utförde Miljöförvaltningen mätningar av dubbdäcksanvändningen på Friggagatan, vid Drottningtorget och i Haga. Vidare användes även mätdata f
This paper discusses the relevance of transient events of strong large-scale ocean evaporation (SLOE) for the deuteriumexcess of marine boundary layer vapor d using a theoretical framework that invokes the closure assumption. We argue that during SLOE events, d is essentially determined by the evaporation flux signature. Distinct high d during SLOE with global-mean values in the range of 12‰-23‰ d
Multi-cell wireless systems usually encounter both intra-cell and inter-cell interference, which can be mitigated via coordinated multipoint (CoMP) transmission. Previous works on multi-cell analysis in the microwave band generally consider fully digital beamforming, requiring a complete radio-frequency chain behind each antenna. This is practically infeasible for millimeter-wave (mmWave) systems
This work demonstrates the sensitivity of lens antenna arrays operating at millimeter-wave (mmWave) frequencies. Considering a Rotman lens array in receive mode, our investigation focuses on its most imperative defect: aberration of electromagnetic (EM) energy. Aberration leads to spillover of electric fields to neighboring ports, reducing the lens' ability to focus the EM energy to a desired port
Lens–based massive multiple–input multiple–output (MIMO) systems have considerable potential to reduce signal processing cost at millimeter–wave frequencies. As a result, they are able to lower the effective channel dimension via beam selection, realized with a network of radio–frequency (RF) switches. However, lens arrays suffer from the inherent quantization of the beamspace, as well as errors d
In this paper, we take a fundamental look at the interference characteristics of a lens-based millimeter-wave (mmWave) multiuser multiple-input multiple-output system (MU-MIMO) system. We consider a hybrid architecture, implemented via a bank of radio-frequency (RF) switches which perform beam selection followed by low-complexity uplink maximum-ratio combining (MRC) at baseband. Considering a Rotm
We consider a massive multiple-input multiple- output system with minimum-mean-squared-error processing on the uplink. A novel analytical framework is proposed to approximate the instantaneous signal-to-interference-plus-noise- ratio (SINR) of an arbitrary user terminal, as well as, the system sum spectral efficiency. Unlike previous studies, our methodology considers spatially correlated Ricean f
Carl Charlier was a Swedish astronomer and statistician. He was influential in making mathematical statistics a university subject in Sweden. His main statistical contribution was the Gram‐Charlier expansions of continuous (Type A) and discrete (Type B) distributions. In astronomy he successfully created a hierarchical galaxy cluster model.
The Asian Summer Monsoons (ASM) represent the main source of precipitation in China and East Asia with about one third of the world population and a region of widespread civilizations. Identifying the temporal and spatial patterns (pathways) of these monsoonal events during the Late Holocene to today has been a matter of debate amongst the scientific community. Here we show that the distribution
The Northern Hemisphere experienced dramatic changes during the last glacial, featuring vast ice sheets and abrupt climate events, while high northern latitudes during the last interglacial (Eemian) were warmer than today. Here we use high-resolution aerosol records from the Greenland NEEM ice core to reconstruct the environmental alterations in aerosol source regions accompanying these changes. S
This package facilitates working with probability distributions by means of Monte-Carlo methods, in a way that allows for propagation of probability distributions through functions. This is useful for, e.g., nonlinear uncertainty propagation. A variable or parameter might be associated with uncertainty if it is measured or otherwise estimated from data. We provide two core types to represent proba
