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Deployment Strategies for Large Intelligent Surfaces

Beyond 5G communication systems must be able to meet the requirements imposed by the ever-increasing demand in capacity, while guaranteeing robustness, reliability, low latency, security, as well as spectral and power efficiencies. Large intelligent surfaces (LIS) as an evolution of massive MIMO have drawn considerable attention among researchers, being already considered as one of the key technol

SPECIES ASSEMBLIES AND SEASONAL SUCCESSION OF DINOFLAGELLATES

Seasonality of dinoflagellate blooms and dinoflagellate assemblies are not random. Yet, bloom events and the specific appearance of species is difficult to predict and sometimes appears stochastic. Nevertheless, it has been established that both abiotic and biotic factors determine species assemblies, as well as the available species pool. The physical environment, especially nutrients and mixing/

Barriers and drivers for sustainable business model innovation based on a radical farmland change scenario

The agricultural sector has a critical role in creating social and environmental value of natural resources in addition to its traditional role of creating economic value by supplying food to the ever-increasing world population. In fulfilling this dual role, the agricultural sector often faces competing pressures: to operate financially profitable businesses and to create, maintain, and benefit f

Lockdown interventions in SIR models : Is the reproduction number the right control variable?

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

Raqqa : A History of the Destruction of Cultural Heritage

In the present paper I will demonstrate the history of Raqqa’s cultural heritage, its floruit and its destruction, from its resettlement in the 19th century until the “Islamic State” period. I will also discuss the recent situation and the challenges to heritage associated with post-war construction in Raqqa. Raqqa was the summer capital of the caliph Harun Al Rashid and the centre of government f

Cold sensitivity and its association to functional disability following a major nerve trunk injury in the upper extremity—A national registry-based study

Aims To investigate self-reported cold sensitivity and functional disability after a repaired major nerve trunk injury in the upper extremity. Methods We identified 735 individuals with a major nerve trunk injury in the upper extremity, surgically treated with direct nerve repair or reconstructed with nerve autografts, in the Swedish national quality registry for hand surgery (HAKIR). Patient-repo

Effects of warm-up exercises on self-assessed vocal effort

Purpose: An elevated sense of vocal effort due to increased vocal demand is frequently reported by patients with voice disorders. However, effects of vocal warm-up on self-assessed vocal effort have not been thoroughly examined. A recently developed version of the Borg CR-10 Scale facilitates vocal effort assessments, following different vocal warm-up tasks. Methods: Effects of a short (5 min) voc

Incorporation of Magnesium into GaN Regulated by Intentionally Large Amounts of Hydrogen during Growth by MOCVD

Herein, metal–organic chemical vapor deposition (MOCVD) of GaN layers doped with Mg atoms to the recognized optimum level of [Mg] ≈2 × 1019 cm−3 is performed. In a sequence of MOCVD runs, operational conditions, including temperature and flow rate of precursors, are maintained except for intentionally larger flows of hydrogen carrier gas fed into the reactor. By employing the largest hydrogen flow

A full-range moisture sorption model for cellulose-based materials yielding consistent net isosteric heat of sorption

A structured approach to derive the water activity function of cellulose-based materials which describe the sorption behavior from dry fiber up to the fiber saturation point is proposed. The coupling between the sorption isotherm and the net isosteric heat of sorption is incorporated in a consistent way, which allows for coupled heat-diffusion problems to be solved. Three different models are deri

Exponential growth of systematic reviews assessing artificial intelligence studies in medicine : challenges and opportunities

The evidence-based medicine (EBM) movement is stepping up its efforts to assess medical artificial intelligence (AI) and data science studies. Since 2017, there has been a marked increase in the number of published systematic reviews that assess medical AI studies. Increasingly, data from observational studies are used in systematic reviews of medical AI studies. Assessment of risk of bias is espe

Inlet layout effects on the mixing performance with a novel mixing evaluation in a powder-fueled ramjet

Mixing process is crucial for ignition and combustion in powder-fueled ramjets. The mixing performance depends mainly on the inlet layout. In this study, the effects of four popular inlet layouts were investigated and were found to significantly influence the particle distribution. In this study, the Savitzky-Golay approach was used to handle large amounts of data on particles to obtain clear peak

Experimental and kinetic modeling study of the CH4+H2S+air laminar burning velocities at atmospheric pressure

With the increasing demand for natural gas and depletion of many sweet gas fields, direct usage of sour gas, usually containing a large percentage of hydrogen sulfide (H2S), becomes a more economical choice in recent years. However, the laminar burning velocity (SL) of CH4+H2S flames have seldom been investigated due to the corrosivity and toxicity of H2S, and no available experimental data can be

Bees increase seed set of wild plants while the proportion of arable land has a variable effect on pollination in European agricultural landscapes

Background and aims – Agricultural intensification and loss of farmland heterogeneity have contributed to population declines of wild bees and other pollinators, which may have caused subsequent declines in insect-pollinated wild plants. Material and methods – Using data from 37 studies on 22 pollinator-dependent wild plant species across Europe, we investigated whether flower visitation and seed

Plasma matrix metalloproteinase 2 is associated with severity and mortality in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a life-threatening disease characterized by vasoconstriction and remodeling of the pulmonary vessels. Risk stratification in PAH could potentially be improved by including novel biomarkers related to PAH pathobiology. We aimed to investigate the relationship between extracellular matrix (ECM)-related proteins, survival, and European Society of Cardiology an

Thermodynamically Favourable States in the Reaction of Nitrogenase without Dissociation of any Sulfide Ligand

We have used combined quantum mechanical and molecular mechanical (QM/MM) calculations to study the reaction mechanism of nitrogenase, assuming that none of the sulfide ligands dissociates. To avoid the problem that there is no consensus regarding the structure and protonation of the E4 state, we start from a state where N2 is bound to the cluster and is protonated to N2H2, after dissociation of H

Global mapping reveals increase in lacustrine algal blooms over the past decade

Algal blooms constitute an emerging threat to global inland water quality, yet their spatial and temporal distribution at the global scale remains largely unknown. Here we establish a global bloom database, using 2.91 million Landsat satellite images from 1982 to 2019 to characterize algal blooms in 248,243 freshwater lakes, representing 57.1% of the global lake area. We show that 21,878 lakes (8.

Presence of Delocalized Ti 3d Electrons in Ultrathin Single-Crystal SrTiO3

Strontium titanate (STO), with a wide spectrum of emergent properties such as ferroelectricity and superconductivity, has received significant attention in the community of strongly correlated materials. In the strain-free STO film grown on the SrRuO3 buffer layer, the existing polar nanoregions can facilitate room-temperature ferroelectricity when the STO film thickness approaches 10 nm. Here we

Tio »väsentliga aktiviteter« framtagna för läkarprogrammen

De 10 EPA som presenteras här (Fakta 1) har tagits fram av läkare och studenter som representerar läkarutbildningarna vid samtliga lärosäten. Utvecklingsarbetet baserades på internationell litteratur och förslagen har genomgått valideringsprocesser [2]. Samtliga avser aktiviteter som ingår i en läkares dagliga arbete och som läkaren ska klara självständigt (i förhållande till handledare) första da

Radial distortion triangulation

This paper presents the first optimal, maximal likelihood, solution to the triangulation problem for radially distorted cameras. The proposed solution to the two-view triangulation problem minimizes the L2-norm of the reprojection error in the distorted image space. We cast the problem as the search for corrected distorted image points, and we use a Lagrange multiplier formulation to impose the ep