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A dissimilar non-matching HDG discretization for Stokes flows

In this work we propose and analyze an HDG method for the Stokes equation whose domain is discretized by two independent polygonal subdomains with different meshsizes. This causes a non-conformity at the intersection of the subdomains or leaves a gap (unmeshed region) between them. In order to appropriately couple these two different discretizations, we propose suitable transmission conditions to

Reductions in greenhouse gas emissions through innovative co-production of bio-oil in combined heat and power plants

Integrating fast pyrolysis into existing biomass-based combined heat and power (CHP) plants offers an innovative opportunity for plant operators to acquire an additional heat sink and produce a renewable transport fuels feedstock. This technology is particularly interesting in Sweden, where biobased heat and power constitute an important part of the energy system. It is important to establish the

Computing Nodal Deficiency with a Refined Dirichlet-to-Neumann Map

Recent work of the authors and their collaborators has uncovered fundamental connections between the Dirichlet-to-Neumann map, the spectral flow of a certain family of self-adjoint operators, and the nodal deficiency of a Laplacian eigenfunction (or an analogous deficiency associated to a non-bipartite equipartition). Using a refined construction of the Dirichlet-to-Neumann map, we strengthen all

Signal-enhanced Raman spectroscopy with a multi-pass cavity for quantitative measurements of formaldehyde, major species and temperature in a one-dimensional laminar DME-air flame

While Raman spectroscopy provides opportunities for simultaneous detection and quantitative analysis of multiple species, it also suffers from certain limitations, such as low signal strength, which often makes it unsuitable for the study of minor species. The present work employs a high-repetition-rate and high-power laser and re-introduces an amplification technique to improve the detection limi

Influence of interface states on built-in electric field and diamagnetic-Landau energy shifts in asymmetric modulation-doped InGaAs/GaAs QWs

The impact of interface defect states on the recombination and transport properties of charges in asymmetric modulation-doped InGaAs/GaAs quantum wells(QWs) is investigated. Three sets of high-mobility InGaAs QW structures are systematically designed and grown by the metal-organic vapor phase epitaxy technique to probe the effect of carrier localization on the electro-optical processes. In these s

Simple and farmer-friendly bumblebee conservation : Straw bales as nest sites in agricultural landscapes

Many bumblebee species are declining due to a loss of semi-natural habitats in agricultural landscapes resulting in diminished forage and nest sites. Anecdotal experience indicates that bumblebees nest in straw bales, but scientific evidence is lacking. We spent 250 h screening for bumblebee nests in 1255 straw bales and ten straw stacks belonging to 58 farms in two intensively farmed Swedish regi

FDA-MIMO radar detection for independent and nonidentically distributed fluctuating targets

Due to its range-dependent target response, frequency diverse array multiple-input multiple-output (FDA-MIMO) radar systems enable superior detection capabilities as compared with conventional phased-array radars. This paper proposes an incoherent detector for airborne FDA-MIMO radar to detect independent but possibly non-identically distributed fluctuating targets. For FDA-MIMO, variations in the

Uncertainty and ignored information in the analysis of bat ultrasound : Bayesian approximation to the rescue

Bat ultrasound analysis has been around for several decades and it is one of the most important tools in studies of bat ecology. Discrimination between species is based on intra-specific features of echolocation calls. Identification of species and genera in audio files can be attempted either manually or through software which performs a fully automated discrimination between species. However, si

Brittle failure of laterally loaded self-tapping screw connections for cross-laminated timber structures

The performance of structural timber connections is of utmost importance since they control the global response of the building. A ductile failure mechanism on the global scale is desirable, especially in the design of structures in seismic areas, where dissipative components in which ductile failure modes need to be ensured are considered. Therefore, the knowledge of possible brittle failure mode

Hypoxia in relationship to tumor volume using hypoxia PET-imaging in head & neck cancer – A scoping review

Background: Hypoxia and large tumor volumes are negative prognostic factors for patients with head and neck squamous cell carcinoma (HNSCC) treated with radiation therapy (RT). PET-scanning with specific hypoxia-tracers (hypoxia-PET) can be used to non-invasively assess hypoxic tumor volume. Primary tumor volume is readily available for patients undergoing RT. However, the relationship between hyp

A flexible approach on pulsed wire magnetic measurement method

The Pulsed Wire (PW) method offers a promising solution for performing local magnetic field measurements in undulators that have limited access that restricts traditional Hall-Probe (HP) measurements. With this technology, undulators can be designed with a closed frame structure, becoming more compact and cost effective. At the same time, the PW method suffers from intrinsic error sources which ca

Health locus of control and all-cause, cardiovascular, cancer and other cause mortality : A population-based prospective cohort study in southern Sweden

The aim was to investigate associations between health locus of control (HLC) and all-cause, cardiovascular (CVD), cancer and other cause mortality. A public health postal questionnaire was distributed in the autumn of 2008 to a stratified random sample of the 18–80 year old adult population in Scania in southernmost Sweden. The participation rate was 54.1%, and 25,517 participants were included i

Investigation of flame characteristics and cooling effectiveness of jet-cooled wall flameholders in vitiated flow

Experimental and numerical studies were performed to understand the flame characteristics and cooling effect of jet-cooled wall flameholders in a simplified augmented combustor. The time-averaged flame structure and wall temperature were investigated employing an instantaneous flame capturing system with image processing technology and a wall temperature measurement system, respectively. Flow and

Non-monotone cellular automata : Order prevails over chaos

We consider a model for the propagation of electrical impulses or activity in a neuronal network. The vertices of a square lattice represent neurons, and the edges of the lattice represent the synaptic connections. Each vertex v is assigned a type: inhibitory or excitatory. The dynamics of propagation of the initial activity captures features of the “integrate-and-fire” model. We study the spread

Graphical modeling of stochastic processes driven by correlated noise

We study a class of graphs that represent local independence structures in stochastic processes allowing for correlated noise processes. Several graphs may encode the same local independencies and we characterize such equivalence classes of graphs. In the worst case, the number of conditions in our characterizations grows superpolyno-mially as a function of the size of the node set in the graph. W

Increased fat mass index is associated with decreased glomerular filtration rate estimated from cystatin C. Data from Malmö Diet and Cancer cohort

Background This study aims to describe associations of obesity and CKD in a Swedish urban population. The impact of fat mass, from bioimpedance analysis, on eGFR based on cystatin C and/or creatinine is studied. Methods 5049 participants from Malmö Diet and Cancer Study the cardiovascular arm (MDCS-CV) with available body mass composition (single frequency bioimpedance analysis) and cystatin C mea

Gender Differences in Tournament Choices: Risk Preferences, Overconfidence, or Competitiveness?

A long line of laboratory experiments has found that women are less likely to sort into competitive environments. Although part of this effect may be explained by gender differences in risk attitudes and self-confidence, previous studies have attributed the majority of the gender gap to gender differences in a competitiveness trait. I re-examine this result using a novel experiment that allows me