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Svenskarna i Hooverville : svenska immigranter i Seattles största kåkstad under den stora depressionen
Impact of matching network on the capacity of compact MIMO systems
MIMO is an undisputed breakthrough in advanced wireless technology, as it offers potentially linear increase in information-theoretic capacity with the number of antennas. However, the implementation of MIMO in compact terminals is a relatively uncharted topic, due to challenging problems with high antenna correlation and mismatch loss, both of which greatly reduces the expected MIMO gains. In thi
Regional atmospheric cooling and wetting effect of permafrost thaw-induced boreal forest loss
In the sporadic permafrost zone of North America, thaw‐induced boreal forest loss is leading to permafrost‐free wetland expansion. These land cover changes alter landscape‐scale surface properties with potentially large, however, still unknown impacts on regional climates. In this study, we combine nested eddy covariance flux tower measurements with satellite remote sensing to characterize the imp
Productivity and evapotranspiration of two contrasting semiarid ecosystems following the 2011 global carbon land sink anomaly
Global carbon balances are increasingly affected by large fluctuations in productivity occurring throughout semiarid regions. Recent analyses found a large C uptake anomaly in 2011 in arid and semiarid regions of the southern hemisphere. Consequently, we compared C and water fluxes of two distinct woody ecosystems (a Mulga (Acacia) woodland and a Corymbia savanna) between August 2012 and August 20
Monitoring boreal forest biomass and carbon storage change by integrating airborne laser scanning, biometry and eddy covariance data
This study presents a comparison and integration of three methods commonly used to estimate the amount of forest ecosystem carbon (C) available for storage. In particular, we examine the representation of living above- and below-ground biomass change (net accumulation) using plot-level biometry and repeat airborne laser scanning (ALS) of three dimensional forest plot structure. These are compared
Methane fluxes from a small boreal lake measured with the eddy covariance method
Fluxes of methane, CH4, were measured with the eddy covariance (EC) method at a small boreal lake in Sweden. The mean CH4 flux during the growing season of 2013 was 20.1 nmol m−2 s−1 and the median flux was 16 nmol m−2 s−1 (corresponding to 1.7 mmol m−2 d−1 and 1.4 mmol m−2 d−1). Monthly mean values of CH4 flux measured with the EC method were compared with fluxes measured with floating chambers (
Intra-annual variability of wood formation and delta C-13 in tree-rings at Hyytiala, Finland
Investigation of the relationship between tree-ring stable carbon isotope composition (δ13C) and environmental variables at the intra-seasonal scale can inform on the understanding of the environmental forcing affecting trees during the active period of radial growth. Recent progress in the measurement techniques for assessing the δ13C signature of tree rings at high spatial resolution provides an
ICESat/GLAS Canopy Height Sensitivity Inferred from Airborne Lidar
Variations in laser properties and data acquisition times introduced inconsistencies in Geoscience Laser Altimeter System (GLAS) data. The effect of data inconsistencies, on two GLAS height retrieval methods, from three study sites, are investigated and validated against airborne laser scanning (ALS) percentile heights, from three data sources: all/first return point clouds, and raster canopy heig
Carbon uptake and water use in woodlands and forests in southern Australia during an extreme heat wave event in the "angry Summer" of 2012/2013
As a result of climate change warmer temperatures are projected through the 21st century and are already increasing above modelled predictions. Apart from increases in the mean, warm/hot temperature extremes are expected to become more prevalent in the future, along with an increase in the frequency of droughts. It is crucial to better understand the response of terrestrial ecosystems to such temp
Risk prediction of atrial fibrillation based on electrocardiographic interatrial block
Background--The electrocardiographic interatrial block (IAB) has been associated with atrial fibrillation (AF). We aimed to test whether IAB can improve risk prediction of AF for the individual person. Methods and Results--Digital ECGs of 152 759 primary care patients aged 50 to 90 years were collected from 2001 to 2011. We identified individuals with P-wave ≥120 ms and the presence of none, 1, 2,
A simple two-dimensional parameterisation for Flux Footprint Prediction (FFP)
Flux footprint models are often used for interpretation of flux tower measurements, to estimate position and size of surface source areas, and the relative contribution of passive scalar sources to measured fluxes. Accurate knowledge of footprints is of crucial importance for any upscaling exercises from single site flux measurements to local or regional scale. Hence, footprint models are ultimate
Effects of harvesting and drought on CO2 and H2O fluxes in an aspen-dominated western boreal plain forest : early chronosequence recovery
This study examines the hydrological recovery of two regenerating boreal trembling aspen (Populus tremuloides Michx.) dominated stands and the sensitivity of that regeneration to drought within the first 5 years of establishment. The results indicate that evapotranspiration fluxes and water-use efficiency rebounded quickly as a result of new vegetation foliage growth and wet conditions found withi
Eddy Covariance Flux Measurements of Gaseous Elemental Mercury Using Cavity Ring-Down Spectroscopy
A newly developed pulsed cavity ring-down spectroscopy (CRDS) system for measuring atmospheric gaseous elemental mercury (GEM) concentrations at high temporal resolution (25 Hz) was used to successfully conduct the first eddy covariance (EC) flux measurements of GEM. GEM is the main gaseous atmospheric form, and quantification of bidirectional exchange between the Earth’s surface and the atmospher
A novel direction of arrival estimation algorithm for WCDMA
Despite the controversies that surround the introduction of the third generation (3G) mobile telecommunication systems, the massive investment by industry and the constant demand for new technology and services are expected to usher in its eventual success. WCDMA is a dominant standard in the 3G system designed to succede the highly successful GSM standard. A new technology proposed for WCDMA is a
Evaluating the use of spatially varying versus bulk average 3D vegetation structural inputs to modelled evapotranspiration within heterogeneous land cover types
The Western Boreal Plain of north‐central Alberta is prone to water‐deficit conditions and is hydrologically sensitive to changes in climate, natural resource extraction and disturbance. Accurate measurement and modelling of the main components of the water balance are important for ecosystem and reclamation management; however, the lack of hydro‐meteorological instrumentation found within differe
Direction of arrival estimation in the presence of correlated signals with non-ideal uniform circular arrays
The Davies transformation is a method to transform the steering vector of a uniform circular array (UCA) to a vector with Vandermonde form. As this form is similar to that of the steering vector of a uniform linear array (ULA), we can apply to UCAs the many tools that have been developed for ULAs. However, the Davies transformation can be highly sensitive to perturbations of the underlying ideal a
Circulating fetuin - A and risk of type 2 diabetes : A mendelian randomization analysis
Fetuin-A, a hepatic-origin protein, is strongly positively associated with risk of type 2 diabetes in human observational studies, but it is unknown whether this association is causal. We aimed to study the potential causal relation of circulating fetuin-A to risk of type 2 diabetes in a Mendelian randomization study with single nucleotide polymorphisms located in the fetuin-A–encoding AHSG gene.
A robust approach to the synthesis of Dolph-Chebyshev beampatterns for uniform circular arrays
The Davies transformation is a method to transform the steering vector of a uniform circular array to another vector with Vandermonde form. However, this transformation can be highly sensitive to perturbations of the underlying ideal array model. In this paper, we describe a method for deriving a more robust transformation using optimisation techniques. The effectiveness of the method is illustrat