Judgements of a speaker’s personality are correlated across differing content and stimulus type

It has previously been shown that first impressions of a speaker’s personality, whether accurate or not, can be judged from short utterances of vowels and greetings, as well as from prolonged sentences and readings of complex paragraphs. From these studies, it is established that listeners’ judgements are highly consistent with one another, suggesting that different people judge personality traits in a similar fashion, with three key personality traits being related to measures of valence (associated with trustworthiness), dominance, and attractiveness. Yet, particularly in voice perception, limited research has established the reliability of such personality judgements across stimulus types of varying lengths. Here we investigate whether first impressions of trustworthiness, dominance, and attractiveness of novel speakers are related when a judgement is made on hearing both one word and one sentence from the same speaker. Secondly, we test whether what is said, thus adjusting content, influences the stability of personality ratings. 60 Scottish voices (30 females) were recorded reading two texts: one of ambiguous content and one with socially-relevant content. One word (~500 ms) and one sentence (~3000 ms) were extracted from each recording for each speaker. 181 participants (138 females) rated either male or female voices across both content conditions (ambiguous, socially-relevant) and both stimulus types (word, sentence) for one of the three personality traits (trustworthiness, dominance, attractiveness). Pearson correlations showed personality ratings between words and sentences were strongly correlated, with no significant influence of content. In short, when establishing an impression of a novel speaker, judgments of three key personality traits are highly related whether you hear one word or one sentence, irrespective of what they are saying. This finding is consistent with initial personality judgments serving as elucidators of approach or avoidance behaviour, without modulation by time or content. All data and sounds are available on OSF (osf.io/s3cxy)

DEVELOPMENT OF THE DIRECT ROVING PLACEMENT TECHNOLOGY (DRP)

The Direct Roving Placement (DRP) technology is in development at the Institute of Composite Structures and Adaptive Systems of the German Aerospace Center (DLR). A fully functional robotic unit that is able to produce dry glass or carbon fiber preforms has been set up at the Center for Lightweight Production Technology (ZLP) in Stade. All relevant process and material parameters that have an influence on the mechanical properties of parts being built with the DRP technology, are investigated. The main advantages of this new fiber placement technology are low material costs and high productivity. The core of the technology, the end-effector, is able to process raw carbon fibers as well as glass fiber rovings. The biggest difference compared to other placement technologies is the integrated online binder application system. The binder system is used to keep the fiber rovings fixed in position, after they have been applied onto a three-dimensional tooling surface. In addition, the online application of a binder provides multiple options of individually tuning the mechanical properties of the preform or the final part

Actuation mechanisms of carbon nanotube-based architectures

State of the art smart materials such as piezo ceramics or electroactive polymers cannot feature both, mechanical stiffness and high active strain. Moreover, properties like low density, high mechanical stiffness and high strain at the same time driven by low energy play an increasingly important role for their future application. Carbon nanotubes (CNT), show this behavior. Their active behavior was observed 1999 the first time using paper-like mats made of CNT. Therefore the CNT-papers are electrical charged within an electrolyte thus forming a doublelayer. The measured deflection of CNT material is based on the interaction between the charged high surface area formed by carbon nanotubes and ions provided by the electrolyte. Although CNT-papers have been extensively analyzed as well at the macro-scale as nano-scale there is still no generally accepted theory for the actuation mechanism. This paper focuses on investigations of the actuation mechanisms of CNT-papers in comparison to vertically aligned CNT-arrays. One reason of divergent results found in literature might be attributed to different types of CNT samples. While CNT-papers represent architectures of short CNTs which need to bridge each other to form the dimensions of the sample, the continuous CNTs of the array feature a length of almost 3 mm, along which the experiments are carried out. Both sample types are tested within an actuated tensile test set-up under different conditions. While the CNT-papers are tested in water-based electrolytes with comparably small redox-windows the hydrophobic CNT-arrays are tested in ionic liquids with comparatively larger redox-ranges. Furthermore an in-situ micro tensile test within an SEM is carried out to prove the optimized orientation of the MWCNTs as result of external load. It was found that the performance of CNT-papers strongly depends on the test conditions. However, the CNT-arrays are almost unaffected by the conditions showing active response at negative and positive voltages. A micro alignment as result of tensile stress can be proven. A comparison of both results point out that the actuation mechanism strongly depends on the weakest bonds of the architectures: Van-der-Waals-bonds vs. covalent C-bond

Implicit perceived vocal trustworthiness negatively correlates with amygdala activation

It has long been established that people make rapid judgements about another’s personality and that these judgements have lasting influence on subsequent decisions and interactions. Particularly, in voice research, it has been shown that one word of less than 500 ms is sufficient for forming first impressions of a speaker, and that listeners highly agree on who sounds trustworthy, or dominant. Furthermore, the rapid first impressions formed within a listener, still hold true after a prolonged exposure of approximately 3 seconds. It has also been suggested that numerous personality traits can be summarised in a two-dimensional space of trustworthiness, and dominance. Given our intrinsic need of survival, and self-preservation, first impressions are aiding decisions as to whether to approach or avoid a person. Neurological evidence however has linked activation in the amygdala (more precisely in the superficial (SF) subdivision) to perceived trustworthiness rather than dominance, implying that the amygdala assists in approach/ avoidance decisions but not in identifying whether a person is physically capable of carrying out threatening behaviour. Despite this clear relationship having been extensively researched with face stimuli, the connection between amygdala activation and perceived vocal trustworthiness is poorly understood. Thus, the current study investigated whether amygdala activation correlated with varying levels of vocal trustworthiness. Furthermore, as there has been an ongoing debate as to whether response patterns were linear or quadratic polynomials in face research, a secondary aim of the current study was to explore response patterns. To achieve that, the study was divided into three experiments. In Experiment 1, vocal word stimuli (‘hello’) were pre-validated online for perceived trustworthiness, and 15 voices per voice sex were selected for the fMRI experiments. Experiment 2 focussed on recording amygdala activity (in the whole and the SF part of the amygdala) across two implicit task designs – a 1-back task (Experiment 2a) requiring a high level of attention and cognitive load, and a PureTone detection task in which attention and cognitive load were lower. It was hypothesised that amygdala activation would be negatively correlated to perceived vocal trustworthiness in male and female voices, irrespective of task. Overall, the hypotheses in these experiments were only partially confirmed as significant correlation values were found for male voices but not female voices. Furthermore, results were task dependent with significant results being observed in the high attention/ cognitive load paradigm (Experiment 2a) but not in the PureTone detection task (Experiment 2b). This suggests that the amygdala is sensitive to modulations in socially relevant vocal characteristics related to approach/avoidance decisions, however, a more varied approach of stimuli selection might be required. Given this study was exploratory in nature, these results should be replicated in a confirmatory analysis on an independent data set with more participants. Furthermore, since this study employed univariate methods, multivariate whole brain analysis would aid in establishing additional neural areas involved in processing vocal trustworthiness

Gibt Keimen keine Chance - Verbundoberflächen mit antimikrobiellen Eigenschaften

Der globale Flugverkehr ist ein stark expansiver Wirtschaftszweig, der sowohl der Luftfahrtindustrie als auch der Tourismusbranche hohe Umsätze ermöglicht. Die Angst vor der Verbreitung des Corona-Virus hat jedoch seit Beginn 2020 z. B. den innerdeutschen Flugverkehr zeitweise um bis zu 75% zurückgehen lassen. Konzepte zur Reduzierung der Keimlast sind zwingend erforderlich. Tatsächlich finden sich im Flugzeug auf den ausklappbaren Tischen und den Sanitäranlagen die größten Keimbelastungen. Um dieses Risiko auch für zukünftige Pandemien zu reduzieren, beschäftigen sich das DLR-Projekt Keimfreies Fliegen und das Luftfahrtforschungsprogramm-Projekt FIONA (Funktions-Integrierte Optimierte Neuartige Additive Strukturen) mit antimikrobiellen Oberflächen. Neben der aerosolbasierten Übertragung mittels kleinster Tröpfchen in der Atemluft, die erfolgreich mit Masken und Luftfiltern reduziert werden kann, liegt der Fokus bei den hier vorgestellten Projekten auf biologischen Oberflächenfilmen und deren energieeffiziente, schneller und dauerhafter Neutralisierung. Dabei soll einerseits mit Faserverbundoberflächen gearbeitet werden, in die antimikrobielle Materialien eingebettet wurden und die gleichzeitig auch thermisch aktiviert werden können. Andererseits wird die Herstellung antimikrobieller Oberflächen durch 3D-Druck untersucht. Die große Designfreiheit der additiven Fertigungstechnologie erlaubt eine schnelle Herstellung funktionsintegrierter Multimaterialbauteile, sodass für die Airlines eine wirtschaftliche Nachrüstung mit antimikrobiellen Kabinenbauteilen möglich ist

Potential of fibre metal laminates in root joints of wind energy turbine rotor blades

The length of rotor blades is showing continuous growth for future wind energy turbines leading to high bending moments, which must be transferred to the hub by the root section. As the growth of the root diameter is limited by factors such as transportability, motivation to improve the load carrying capacity without changing the geometry is high. Hybridisation with metals shows a possibility to intrinsically increase the bearing strength of fibre-reinforced plastics. This publication presents experimental investigations into hybrid laminates to be used in so-called T-joints for connecting rotor blades to the hub of the nacelle of a wind energy turbine. An overview is given about the bearing strength of several material combinations hybridising glass- and carbon fibre-reinforced plastics (GFRP, CFRP) with aluminium, titanium and steel alloys. A GFRP-steel-hybrid can be identified as a material with a high reinforcing effect even for low amounts of steel. A hybrid T-joint demonstrator is manufactured by resin infusion and tested under static tension. In comparison with a GFRP reference, a joining strength increase of about 33% is achieved for a steel content of 3%. Further coupon level tests reveal a weak spot in the transition zone between the monolithic GFRP region and full hybrid region as the static and fatigue resistance clearly decreases in comparison with monolithic GFRP and full hybrid references

The effect of graphene oxide (GO) nanoparticles on the processing of epoxy/glass fiber composites using resin infusion

In this paper, the effects of graphene oxide (GO) nanoparticles on glass fiber composite processing by incorporating them into epoxy resin were investigated. GO was synthesized from graphite powder and was mixed with epoxy resin. Three different GO contents of 0.05, 0.1, and 0.2 wt% were used. Epoxy/GO samples were tested for rheology and cure kinetics to evaluate the effects of GO content on important resin infusion processing parameters. The results show that adding GO to neat epoxy resin increased the viscosity and affected the resin cure reaction by reducing the resin gel time. After that, glass fiber composites were prepared using the resin infusion process. Samples with 0.2 wt% GO result in very slow resin infiltration time with premature resin gelation. A 30 % increase in flexural strength and a 21 % increase in flexural modulus are manifested by adding GO as the secondary reinforcement to glass fiber composites

Bioinspired approaches for toughening of fibre reinforced polymer composites

In Nature, there are a large range of tough, strong, lightweight and multifunctional structures that can be an inspiration to better performingmaterials. Thiswork presents a review of structures found in Nature, frombiological ceramics and ceramics composites, biological polymers and polymers composites, biological cellular materials, biological elastomers to functional biological materials, and their main tougheningmechanisms, envisaging potential mimicking approaches that can be applied in advanced continuous fibre reinforced polymer (FRP) composite structures. For this, themost common engineering compositemanufacturing processes and current composite damage mitigation approaches are analysed. This aims at establishing the constraints of biomimetic approaches development as these bioinspired structures are to be manufactured by composite technologies. Combining both Nature approaches and engineering composites developments is a route for the design and manufacturing of high mechanical performance and multifunctional composite structures, therefore new bioinspired solutions are proposed.This research was funded by the project “IAMAT—Introduction of advanced materials technologies into new product development for the mobility industries”, with reference MITP-TB/PFM/0005/2013, under the MIT-Portugal program and in the scope of projects with references UIDB/05256/2020 and UIDP/05256/2020, exclusively financed by FCT - Fundação para a Ciência e Tecnologia

Investigations of the key mechanism of Carbon-Nanotube Actuators and their dependencies

Future adaptable applications require electro-mechanical actuators with a high weight-related en-ergy. Among modern multi-functional materials carbon nanotubes (CNTs) have some special char-acteristics which give them the potential to solve this demand. On the one hand raw CNTs have excellent mechanical properties like their low density (1330kg/m$^3$) and very high estimated stiffness of about 1TPa. On the other hand CNTs have the ability under presence of ions, wired like a capacitor and activated by a charge injection to perform a dimension-change (length of C-C bondings). Calculations and experiments present achievable active strains of 1$\%$ at low voltage of $\pm$1V what qualifies CNT-based materials for leightweight powerful actuators. In this paper the former work done with actuators using CNT-containing mats and Nafion as solid electrolyte is evaluated by analyzing the two main-components in more detail. On the one hand the CNT-based model-material SWCNT-mats called Bucky-paper (BP) and on the other hand ion do-nating electrolytes in liquid-phase like a NaCl-solution and its solid equivalent Nafion as thin-foils are tested. Additional methods of fabrication, preparation and characterization of the CNT-powder and the manufactured BPs containing randomly oriented single-walled carbon nanotubes (SWCNTs) are presented which provide a deeper system-understanding. Both materials (BPs and Nafion-foils) are intensively investigated in different deflection-test-rigs due to their structural as-sembly. This paper presents a method for electro-mechanical measurements of BPs in an in-plain test set-up which avoids sensing secondary effects like thermal expansion or mass-transport and confirm that BP-deflection should only be a capacity-driven effect. Nafion as solid electrolyte will be tested in an out-of-plane facility to measure its possible actuation within the lamellar-direction. With this approach the dependencies of each component and their individual characters on the deflec-tion can be estimated. The active response can be referred to the internal structure of both compo-nents as well as of the whole structural assembly. The results give a certain direction to a BP-optimization referring to active strain, density, structural integrity and conductibility. In addition to these facts the active character of BPs using CNTs of different suppliers and Nafion is analyzed. These investigations are of particular importance for detection of global dependencies and using both materials in a hybrid-assembly like solid actuators which are needed for structural applications