GRO.publications
Not a member yet
137257 research outputs found
Sort by
Parametric analysis of geothermal reservoir performance in Mesozoic sandstone formations within the North German Basin developed by multi-well systems
No full textAbstract In the context of the heat transition in Germany, the decarbonization of the heating and cooling industry via renewable energy sources requires the usage of comprehensive strategies and novel engineering solutions. With regard to district heating in urban areas, middle-deep geothermal resources offer a great potential which has not been fully utilized yet due to the required minimum temperature of district heating networks, leading to the additional employment of industrial and high-capacity-power heat pumps. However, the controlling factors on the optimal and sustainable development of those middle-deep geothermal resources are not fully elucidated yet. By evaluating numerical approaches against analytical model solutions, this work systematically analyzes the impact of reservoir quality and operational controlling factors on the performance of Mesozoic sandstone reservoirs in the North German Basin (NGB) targeted by multi-well arrangements. For the first time, we compare in a comprehensive manner previous analytical model results with our numerical findings to characterize more broadly the quantitative influence of different controlling factors on the thermal breakthrough occurrence time, the maximum cooling rate after the occurrence of the thermal breakthrough and the end production temperature. Moreover, we especially focus and illustrate the controls on the behavior of the production temperature after the thermal breakthrough has occurred and conduct a one-factor-at-a-time (OAT) parametric sweep analysis with regard to the thermal utilization time or life span of a geothermal facility. Based on our numerical results, we set up a ranking scheme showing the influence of varying controlling parameters on the considered performance parameters. One of the striking findings of our scenario analysis relates to the thermal breakthrough occurrence time, which is 17 ± 3% higher for a geothermal doublet array compared to a single doublet. Yet, the maximum cooling rate of the production temperature after the thermal breakthrough is higher for the array layout, depending on the number of neighboring injection wells. Our comprehensive numerical study, therefore, illustrates in detail the complex thermo-hydraulic interaction of geothermal doublet arrays, the controls on the defined thermal lifetime as well as the optimization possibilities of middle-deep geothermal resources.German Federal Ministry for Economic Affairs and Climate ActionLeibniz-Institut für Angewandte Geophysik http://dx.doi.org/10.13039/50110000411
The performance of missing transverse momentum reconstruction and its significance with the ATLAS detector using 140 fb - 1 of s = 13 TeV pp collisions
No full textAbstract This paper presents the reconstruction of missing transverse momentum ( p T miss ) in proton–proton collisions, at a center-of-mass energy of 13 TeV. This is a challenging task involving many detector inputs, combining fully calibrated electrons, muons, photons, hadronically decaying τ -leptons, hadronic jets, and soft activity from remaining tracks. Possible double counting of momentum is avoided by applying a signal ambiguity resolution procedure which rejects detector inputs that have already been used. Several p T miss ‘working points’ are defined with varying stringency of selections, the tightest improving the resolution at high pile-up by up to 39% compared to the loosest. The p T miss performance is evaluated using data and Monte Carlo simulation, with an emphasis on understanding the impact of pile-up, primarily using events consistent with leptonic Z decays. The studies use 140 fb - 1 of data, collected by the ATLAS experiment at the Large Hadron Collider between 2015 and 2018. The results demonstrate that p T miss reconstruction, and its associated significance, are well understood and reliably modelled by simulation. Finally, the systematic uncertainties on the soft p T miss component are calculated. After various improvements the scale and resolution uncertainties are reduced by up to 76 % and 51 % , respectively, compared to the previous calculation at a lower luminosity
"We've Met Some Problems": Developers' Issues with Privacy-Preserving Computation Techniques on Stack Overflow
No full textCorrelations of neural predictability and information transfer in cortex and their relation to predictive coding
No full textPredictive-coding like theories agree in describing top-down communication through the cortical hierarchy as a transmission of predictions generated by internal models of the inputs. With respect to the bottom-up connections, however, these theories differ in the neural processing strategies suggested for updating the internal model. Some theories suggest a coding strategy where unpredictable inputs, i.e., those not captured by the internal model, are passed on through the cortical hierarchy, whereas others claim that the predictable part of the inputs is passed on. Here, we addressed which neural coding strategy is employed in cortico-cortical connections using an information-theoretic approach. Our framework allows for quantifying two core aspects of both strategies, namely, predictability of inputs and information transfer, through local active information storage and local transfer entropy, respectively. A previous study on the neural processing of retinal ganglion cells connected to the lateral geniculate nucleus showed a coding for predictable information, captured by an increase in the information transfer with the predictability of inputs. Here, we further investigate predictive coding strategies at the cortical level. In particular, we analyzed LFP activity obtained from intracranial EEG recordings in humans and spike recordings from mouse cortex. We detected cortico-cortical connections with increasing information transfer with the predictability of inputs in recorded channels from frontal, parietal and temporal areas in human cortex. In the mouse visual system, we detected connections exhibiting both an increase and decrease in the information transfer with input predictability, although the former was pre-dominant. Our evidence supports the presence of both predictive coding strategies at the cortical level, with a potential predominance of encoding for predictable information
Massively Multi-person 3D Human Motion Forecasting with Scene Context
No full textForecasting long-term 3D human motion is challenging: the stochasticity of human behavior makes it hard to generate realistic human motion from the input sequence alone. Information on the scene environment and the motion of nearby people can greatly aid the generation process. We propose a scene-aware social transformer model (SAST) to forecast long-term (10 s) human motion motion. Unlike previous models, our approach can model interactions between both widely varying numbers of people and objects in a scene. We combine a temporal convolutional encoder-decoder architecture with a Transformer-based bottleneck that allows us to efficiently combine motion and scene information. We model the conditional motion distribution using denoising diffusion models. We benchmark our approach on the Humans in Kitchens dataset, which contains 1 to 16 persons and 29 to 50 objects that are visible simultaneously. Our model outperforms other approaches in terms of realism and diversity on different metrics and in a user study. The code is available at https://github.com/felixbmuller/SAST
Genetic diversity and fine-scale spatial genetic structure of European beech populations along an elevational gradient
No full textDifferences in environmental conditions can shape the level and distribution of intraspecific genetic variation between and within populations. Elevational gradients are characterised by strong variation in environmental conditions on a short spatial scale and provide an ideal setting to study the spatial distribution of genetic diversity. Therefore, we investigated the genetic diversity, fine-scale spatial genetic structure (FSGS) and spring phenology (bud burst) as a proxy for flowering of five European beech (Fagus sylvatica L.) populations along an elevational gradient, ranging from about 550 m to 1450 m a.s.l. in the Romanian Carpathians. Using microsatellite and genome-wide single nucleotide polymorphism (SNP) markers, we observed a slight decrease in genetic diversity with increasing elevation and low population differentiation. Furthermore, levels of FSGS decreased with elevation along the gradient. We could not detect any significant effects of spring phenological traits on the level of FSGS probably because many different environmental factors and processes vary over the years and contribute to shaping the FSGS. The slightly lower genetic diversity in high elevation populations may indicate stronger drift effects and could be due to the marginal ecological conditions and the lower abundance of beech. However, in these stands with less competing crowns and a more open forest structure, pollen dispersal might be longer ranging in this wind pollinated species which could contribute to a weaker FSGS. The knowledge about the level and structure of genetic variation along environmental gradients is crucial to inform forest and conservation management especially in the face of climate change
The deep winding at the brain surface: replicating a historical report associating the 'bridged' central sulcus with the pli de passage fronto-pariétal moyen
No full textIn 1876, the anatomist Heschl surveyed 1,087 brains identifying six cases of a unilateral ‘bridged’ central sulcus (CS) at the brain surface. He also measured the height of a minor ‘deep winding’ at the same location within the CS in the remaining 1,081 brains, reporting a distribution skewed towards significantly increased heights. These observations supported his hypothesis that the ‘bridged’ CS represents an extreme form of the ‘deep winding’ within the CS. In this replication we examined structural MRI data from an equally large dataset of 1,112 participants of the Human Connectome Project young adult (HCP-YA) dataset. Through visual inspection, we identified nine cases of a ‘bridged’ CS, confirming its prevalence of less than 1%. The height of the ‘deep winding’, referred to in the HCP-YA dataset as the pli de passage fronto-pariétal moyen (PPfpm), was extracted from 1,983 MRI-based hemispheric depth profiles. The resulting PPfpm height distribution, although wider, still mirrored Heschl’s findings, showing a similar skew towards larger heights. Further analyses of the twin data within the HCP-YA dataset indicated a slightly increased prevalence of the ‘bridged’ CS in monozygotic and dizygotic twins compared to non-twin individuals, though no concordance of ‘bridged’ CS was observed in monozygotic twin pairs. This replication study validates both of Heschl’s observations, describes additional factors that might influence the prevalence of the ‘bridged’ CS, and refines the characterization of the ‘deep winding’ height distribution. Together, these findings reaffirm and expand historical insights into the intricate anatomical organization of the CS
Toward independence: maternal social status and experience shape mother–infant relationships in mandrills
No full textPrecision measurement of the B 0 meson lifetime using B 0 → J / ψ K ∗ 0 decays with the ATLAS detector
No full textAbstract A measurement of the B 0 meson lifetime using B 0 → J / ψ K ∗ 0 decays in data from 13 TeV proton–proton collisions with an integrated luminosity of 140 fb - 1 recorded by the ATLAS detector at the LHC is presented. The measured effective lifetime is τ = 1.5053 ± 0.0012 ( stat . ) ± 0.0035 ( syst . ) ps . The average decay width extracted from the effective lifetime, using parameters from external sources, is Γ d = 0.6639 ± 0.0005 ( stat . ) ± 0.0016 ( syst . ) ± 0.0038 (ext.) ps - 1 , where the uncertainties are statistical, systematic and from external sources. The earlier ATLAS measurement of Γ s in the B s 0 → J / ψ ϕ decay was used to derive a value for the ratio of the average decay widths Γ d and Γ s for B 0 and B s 0 mesons respectively, of Γ d Γ s = 0.9905 ± 0.0022 (stat.) ± 0.0036 (syst.) ± 0.0057 (ext.) . The measured lifetime, average decay width and decay width ratio are in agreement with theoretical predictions and with measurements by other experiments. This measurement provides the most precise result of the effective lifetime of the B 0 meson to date
Cardiovascular magnetic resonance imaging and endomyocardial biopsy in giant cell myocarditis: a case report on diagnostic challenges and future perspectives
No full textGiant cell myocarditis (GCM) is a rare but often fast-progressing cardiac disease with a high risk of poor outcome. Nonetheless, its differentiation from other diseases like cardiac sarcoidosis (CS) using cardiovascular magnetic resonance imaging (CMR) remains challenging.Open-Access-Publikationsfonds 202