Distributed Multicell Beamforming Design Approaching Pareto Boundary with Max-Min Fairness

This paper addresses coordinated downlink beamforming optimization in multicell time-division duplex (TDD) systems where a small number of parameters are exchanged between cells but with no data sharing. With the goal to reach the point on the Pareto boundary with max-min rate fairness, we first develop a two-step centralized optimization algorithm to design the joint beamforming vectors. This algorithm can achieve a further sum-rate improvement over the max-min optimal performance, and is shown to guarantee max-min Pareto optimality for scenarios with two base stations (BSs) each serving a single user. To realize a distributed solution with limited intercell communication, we then propose an iterative algorithm by exploiting an approximate uplink-downlink duality, in which only a small number of positive scalars are shared between cells in each iteration. Simulation results show that the proposed distributed solution achieves a fairness rate performance close to the centralized algorithm while it has a better sum-rate performance, and demonstrates a better tradeoff between sum-rate and fairness than the Nash Bargaining solution especially at high signal-to-noise ratio.Comment: 8 figures. To Appear in IEEE Trans. Wireless Communications, 201

Low Complexity Estimation of Angular Spread with an Antenna Array

: When sensor array processing is applied in for example mobile communication applications, more parameters than the direction of arrival are necessary to properly describe the propagation channel. Here, a new low complexity algorithm is proposed for estimation of the angular spread caused by local scattering around a mobile source. The algorithm uses the root-MUSIC algorithm to fit two point sources to the data received from a single scattered source and the two estimated values are used to calculate both direction of arrival and spread angle. The performance is calculated analytically and verified through simulations. Keywords: Adaptive arrays, Antennas, Communication channels, Parameter estimation, Subspace methods 1. INTRODUCTION Much work has been done in the area of sensor array processing under the assumption of point sources with direct wave paths to the antenna array. A more realistic model for e.g. mobile communication situations must take multipath propagation int..

Associations between Bovine Coronavirus and Bovine Respiratory Syncytial Virus Infections and Productivity, Health Status and Occurrence of Antimicrobial Resistance in Swedish Dairy Herds

Bovine respiratory syncytial virus (BRSV) and bovine coronavirus (BCoV) affect dairy herds worldwide. In this study, effects on herd health, morbidity, and antimicrobial resistance (AMR) were assessed. Herds were considered free of infection (FREE), recently infected (RI) or past steadily infected (PSI) based on antibody testing of milk from primiparous cows. Data from farm records, national databases, and AMR of fecal Escherichia coli from calves were used as outcome variables. Compared to BRSV FREE herds: BRSV PSI herds had significantly higher odds of cough in young stock, a higher proportion of quinolone-resistant E. coli (QREC), but a lower proportion of cows with fever. BRSV RI herds had significantly higher odds of diarrhea in calves and young stock, a higher proportion of QREC and higher odds of multidrug-resistant E. coli. Compared to BCoV FREE herds: BCoV PSI herds had significantly higher odds of cough in all ages, and of diarrhea in young stock and cows, and a higher proportion of cows with fever. BCoV RI herds had significantly higher odds of diarrhea in young stock and cows and of cough in all ages. The results support previous research that freedom from BRSV and BCoV is beneficial for animal welfare and farm economy and possibly also mitigates AMR

Signal Waveform Estimation from Array Data in Angular Spread Environment

We analyze different direction based signal copy algorithms for a model of angular spread caused by local scattering around each signal source. Optimal algorithms, in terms of Signal to Interference and Noise ratio, are derived for both rapidly and slowly time varying angular spread and a low complexity ad-hoc algorithm is suggested. Simulations show that these algorithms outperform traditional signal copy algorithms in terms of Signal to Interference and Noise ratio as well as outage probability. 1. Introduction Several principles have been suggested for signal waveform estimation in sensor array processing [2, 3, 4, 7]. Here we analyze direction based signal copy algorithms in a scenario with multipath-induced angular spread, where the ordinary point source model is not well suited. This model is relevant in applications such as mobile communications where non line of sight is common. The signal to interference plus noise ratio (SINR) and outage probability are used as quality measu..

Therapeutic drug monitoring of escitalopram in an outpatient setting

The main objectives of this study were to outline the inter-and intraindividual and overall pharmacokinetic variability of S-citalopram, S-desmethylcitalopram, and S-didesmethylcitalopram in serum by means of therapeutic drug monitoring; and to investigate potential correlations between the serum concentration and simultaneously collected clinical data. The study was conducted on outpatients in Sweden in 2002 to 2005. Included in the pharmacokinetic evaluation were 155 patients (68% women and 32% men) aged 17 to 95 years (average, 51 years). One serum sample per patient, taken as a trough value insteady state, was assessed. For the inter- and intraindividual variation calculation, 16 patients were included with two eligible samples each. The median daily dose was 20 mg/day (range, 5-40 mg). Extensive overall serum concentration variability was seen for all dose levels. The interindividual coefficient of variation for dose-normalized concentrations was 71% for S-citalopram, 36% for S-desmethylcitalopram, and 50% for S-didesmethylcitalopram. The intraindividual variations over time for the same parameters were approximately 30%, except for the ratio S-desmethylcitalopram/Scitalopram, which was 23%. The median S-desmethylcitalopram level was approximately 60% of the parent substance and the S-didesmethylcitalopram level approximately 9%. Higher age was correlated with higher serum concentrations, but no gender-related concentration differences were found. A majority (76%) of the patients took one or more drugs in addition to escitalopram, but concomitant medication did not seem to interact with escitalopram. However, women taking oral contraceptives showed a lower metabolic ratio compared with age-matched women. As a result of the wide range of the ratio in this population, these findings are not considered of clinical relevance

Decreased detection of ESBL- or pAmpC-producing Escherichia coliin broiler breeders imported into Sweden

In the spring of 2010, it was discovered that a large proportion of broilers in Sweden were colonized withEscherichia coliproducing extended-spectrum beta-lactamases (ESBL) or plasmid mediated AmpC (pAmpC). It was hypothesized that the high prevalence was due to transfer from an upper level in the production pyramid and sampling upwards in the production pyramid was initiated. From 2010 to 2019, all shipments (n = 122) of broiler breeders were screened on arrival to Sweden for the occurrence of ESBL- or pAmpC-producingE. coliusing selective methods. Samples of paper linings from shipments of breeders were cultured on MacConkey agar supplemented with cefotaxime (1 mg/L) after pre-enrichment in either MacConkey broth with cefotaxime (1 mg/L), or from late June 2015 in buffered peptone water without antibiotics. ESBL- or pAmpC-producingE. coliwas isolated from 43 (35%) of these. Over the years, the proportion of positive imports have decreased and during 2018 and 2019 all imports were negative. In conclusion, the occurrence of ESBL- or pAmpC-producingE. coliin broiler breeders on arrival to Sweden has decreased. Such bacteria have not been detected in any shipments since 2017.Funding Agencies|Swedish Board of Agriculture [6.2.18-14284/2018]; National Veterinary Institute (SVA), Uppsala, Sweden</p

Kungl Tekniska Hgskolan

We analyze different direction based signal copy algorithms for a model of angular spread caused by local scattering around each signal source. Optimal algorithms, in terms of Signal to Interference and Noise ratio, are derived for both rapidly and slowly time varying angular spread and a low complexity ad-hoc algorithm is suggested. Simulations show that these algorithms outperform traditional signal copy algorithms in terms of Signal to Interference and Noise ratio as well as outage probability. 1. Introduction Several principles have been suggested for signal waveform estimation in sensor array processing [2, 3, 4, 7]. Here we analyze direction based signal copy algorithms in a scenario with multipath-induced angular spread, where the ordinary point source model is not well suited. This model is relevant in applications such as mobile communications where non line of sight is common. The signal to interference plus noise ratio (SINR) and outage probability are used as quality meas..