Radial basis function interpolation for black-box multi-physics simulations

Interpolation based on radial basis functions (RBF) is a standard data map- ping method used in multi-physics coupling. It works on scattered data without requiring additional mesh topology or neighborhood information of support points. However, sys- tem matrices of the equations for the coefficients tend to be ill-conditioned. In this work, we illustrate the problem by a simple example and discuss possible remedies. Furthermore, we investigate the numerical performance of this method on uniform and non-uniform meshes with a particular focus on the coupling of black-box components where typically no information about the underlying discretization can be extracted. Radial basis func- tion interpolation usually uses an enhancement of the radial basis functions by a global polynomial in order to properly capture constant components and linear trends in the given data. We present a method that determines this polynomial independent from the radial basis function ansatz, which substantially improves the condition number of the remaining RBF system. Furthermore, we show that a rescaling approach can be used to either increase the accuracy or improve the condition number even further by choosing radial basis functions with a smaller support radius. The results represent an intermediate state with the aim to be integrated into the multi-physics coupling library preCICE

The influence of stimulus ambiguity on category and attitude formation

Existing research on categorical ambiguity has mostly examined how consumers assimilate new products into familiar product categories. Extending these findings, this research investigates whether and under what circumstances consumers either create new mental categories for hybrid products or integrate them into existing categories. Specifically, we propose that this effect is influenced by the degree of product ambiguity and the availability of a new category label. We find that as ambiguity increases, the probability of new category creation augments, but product evaluation deteriorates. However, we also find that a new category label can reduce the effects of ambiguity and can improve product evaluation. Thus, the results fill the existing gap in research on the cognitive integration of hybrid products and shed light on how managers may position these products successfull

CFD/CSD Coupling for an Isolated Rotor Using preCICE

Modeling a rotor blade flow field involves computing the blade motion, elastic deformation, and the three-dimensional forces and moments for specific trim conditions. Such a complex multiphysics problem, which includes a strong fluid-structure interaction, should be modeled by coupling separate solvers which are specialized on solving single-physics problems. In this work, we present a modular and extensible TAU-CAMRAD II coupling environment using the preCICE coupling library [1]. In this coupling, the aerodynamic forces and moments were computed with the CFD solver TAU. The blade control angle for the CFD simulation were determined by the CSD solver CAMRAD II. We validated the implementation using a modified model of the HART-II rotor at an advancing ratio of µ=0.3. Besides the potential that this work unlocks for future simulations of an active rotor, it also serves as an example of using preCICE for geometric multi-scale (1D-3D) coupling of closed-source solvers for periodic phenomena

Atypical neural responses to vocal anger in attention-deficit/hyperactivity disorder

Background Deficits in facial emotion processing, reported in attention-deficit/hyperactivity disorder (ADHD), have been linked to both early perceptual and later attentional components of event-related potentials (ERPs). However, the neural underpinnings of vocal emotion processing deficits in ADHD have yet to be characterised. Here, we report the first ERP study of vocal affective prosody processing in ADHD. Methods Event-related potentials of 6–11-year-old children with ADHD (n = 25) and typically developing controls (n = 25) were recorded as they completed a task measuring recognition of vocal prosodic stimuli (angry, happy and neutral). Audiometric assessments were conducted to screen for hearing impairments. Results Children with ADHD were less accurate than controls at recognising vocal anger. Relative to controls, they displayed enhanced N100 and attenuated P300 components to vocal anger. The P300 effect was reduced, but remained significant, after controlling for N100 effects by rebaselining. Only the N100 effect was significant when children with ADHD and comorbid conduct disorder (n = 10) were excluded. Conclusion This study provides the first evidence linking ADHD to atypical neural activity during the early perceptual stages of vocal anger processing. These effects may reflect preattentive hyper-vigilance to vocal anger in ADHD

Event-Related Potentials and Emotion Processing in Child Psychopathology

In recent years there has been increasing interest in the neural mechanisms underlying altered emotional processes in children and adolescents with psychopathology. This review provides a brief overview of the most up-to-date findings in the field of Event-Related Potentials (ERPs) to facial and vocal emotional expressions in the most common child psychopathological conditions. In regards to externalising behaviour (i.e. ADHD, CD), ERP studies show enhanced early components to anger, reflecting enhanced sensory processing, followed by reductions in later components to anger, reflecting reduced cognitive-evaluative processing. In regards to internalising behaviour, research supports models of increased processing of threat stimuli especially at later more elaborate and effortful stages. Finally, in autism spectrum disorders abnormalities have been observed at early visual-perceptual stages of processing. An affective neuroscience framework for understanding child psychopathology can be valuable in elucidating underlying mechanisms and inform preventive intervention

Consumer Evaluations of Competing Brands: Perceptual versus Predictive Validity

This study applies the concepts of consumer predictive and confidence values of information to consumer evaluations of food quality. Examining hypothetical findings from a thought experiment, the study offers advances in cue utilization, predictive validity, and achievement of consumer's perceived quality and actual quality. Separately, metrics for these concepts were applied in a consumer product-quality evaluation study of three brands of peanut butter. Actual quality was operationally defined in terms of Consumers Union ratings of the peanut butter. Using a between-groups, posttest only experimental design, female graduate students (n = 98) tasted and rated one of three peanut butters on the basis of quality and nine product attributes. These informants received no knowledge of brand names or comparative qualities prior to the test. The analysis indicates a nonsignificant correlation between actual quality of the brands and quality as perceived by the informants. The major cues used by informants in making their qualitative judgments (cue utilization) differed from the significant dimensions associated with actual quality (predictive validity). The findings inform the suggestion for consumer training in the process of making accurate quality evaluations