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Supercooled large droplet (SLD) icing can occur behind the protected surfaces of an aircraft and create severe aerodynamic disturbances, which represent a safety hazard for aviation. Liquid water content (LWC) measurements in icing conditions that contain SLDs require instruments that are able to sample unimodal and bimodal droplet size distributions with droplet diameters from 2 to 2000 µm. No standardized detection method exists for this task. A candidate instrument, which is currently used in icing wind tunnel (IWT) research, is the Nevzorov probe. In addition to the standard 8 mm total water content (TWC) collector cone, a novel instrument version also features a 12 mm diameter cone, which might be advantageous for collecting the large droplets characteristic of SLD conditions. In the scope of the two EU projects, SENSors and certifiable hybrid architectures for safer aviation in ICing Environment (SENS4ICE) and ICE GENESIS, we performed measurement campaigns in SLD icing conditions in IWTs in Germany, Austria and the USA. We obtained a comprehensive data set of measurements from the LWC sensor, the 8 mm cone sensor and the 12 mm cone sensor of the Nevzorov probe, and from the tunnel reference instrumentation. In combination with measurements of the particle size distribution, we experimentally derive a collision efficiency curve that is based on a suitable functional form for the new 12 mm cone for median volume diameters (MVDs) between 12 and 58 µm and wind tunnel speeds from 40 to 85 m s−1. Knowledge of this curve allows us to correct the LWC measurements of the 12 mm cone (LWC12) in particular for the inevitably high decrease in collision efficiency for small droplet diameters. In unimodal SLD conditions, with MVDs between 128 and 720 µm, LWC12 generally agrees within ±20 % with the tunnel LWC reference values from a WCM-2000 and an isokinetic probe. An increase in the difference between LWC12 and the WCM-2000 measurements at larger MVDs indicates better droplet collection properties of the 12 mm cone. Similarly, the favorable detector dimensions of the 12 mm cone explain a 7 % enhanced detection efficiency compared to the 8 mm cone; however this difference falls within the instrumental uncertainties. Data collected in various bimodal SLD conditions with MVDs between 16 and 534 µm and LWCs between 0.22 and 0.72 g m−3 also show an agreement within ±20 % between LWC12 and the tunnel LWC, which demonstrates the suitability of the Nevzorov sensor head with the 12 mm cone for measurements of LWC in Appendix O icing conditions.

When the politician Roman Haider of the party Freiheitliche Partei Österreichs (FPÖ--Freedom Party of Austria) caused the interruption of a lecture about political extremism in an Austrian school in spring 2017, a heated debate erupted over the place of politics in school education. While Haider accused the lecturer of political propaganda, teachers, students and political opponents were upset about this seeming act of censorship. The controversy raises important questions over the aims and principles of civic education, which will continue to engage teachers and educationalists.

This work describes the latest design, calibration and application of a near-infrared laser diode-based photoacoustic (PA) hygrometer developed for total water content measurement in simulated atmospheric freezing precipitation and high ice water content conditions with relevance in fundamental icing research, aviation testing, and certification. The single-wavelength and single-pass PA absorption cell is calibrated for molar water vapor fractions with a two-pressure humidity generator integrated into the instrument. Laboratory calibration showed an estimated measurement accuracy better than 3.3 % in the water vapor mole fraction range of 510–12 360 ppm (5 % from 250–21 200 ppm) with a theoretical limit of detection (3σ) of 3.2 ppm. The hygrometer is examined in combination with a basic isokinetic evaporator probe (IKP) and sampling system designed for icing wind tunnel applications, for which a general description of total condensed water content (CWC) measurements and uncertainties are presented. Despite the current limitation of the IKP to a hydrometeor mass flux below 90 gm-2s-1, a CWC measurement accuracy better than 20 % is achieved by the instrument above a CWC of 0.14 g m−3 in cold air (−30 ∘C) with suitable background humidity measurement. Results of a comparison to the Cranfield University IKP instrument in freezing drizzle and rain show a CWC agreement of the two instruments within 20 %, which demonstrates the potential of PA hygrometers for water content measurement in atmospheric icing conditions.

Lithium-ion batteries (LIBs) are commonly used in today’s electric vehicles. Studying their behaviour under mechanical loading, including short circuits, is vital for vehicle safety. This paper covers three major topics, (1) a general literature review for the state-of-the-art of LIBs, (2) physical cell tests for model validation are performed, wherein the occurrence of short circuits is detected and (3) creating a finite element model (FEM) of an 18650 cylindrical LIB using the most recent testing and simulation techniques. A variety of short-circuit criteria based on stresses, strains and geometric parameters have been implemented in the simulation and compared to the test results. It will be demonstrated that a combination of two geometric criteria, in the radial and axial directions of the cell, is best suited for virtual short-circuit detection in the simulation. Finally, the short-circuit criteria are implemented in a post-processing tool that allows fast short-circuit analysis of cells of different loadings. In the future, this method of short-circuit detection will be used to analyse an assembly of several battery cells such as, for instance, an automotive or maritime battery pack. Furthermore, the developed method enables mechanical integration with respect to crash safety in vehicles.

Social sciences and humanities (SSH) research is divided across a wide array of disciplines, sub-disciplines and languages. While this specialization makes it possible to investigate the extensive variety of SSH topics, it also leads to a fragmentation that prevents SSH research from reaching its full potential. The TRIPLE project brings answers to these issues by developing an innovative discovery platform for SSH data, researchers’ projects and profiles. Having started in October 2019, the project has already three main achievements that are presented in this paper: (1) the definition of main features of the GOTRIPLE platform; (2) its interoperability; (3) its multilingual, multicultural and interdisciplinary vocation. These results have been achieved thanks to different methodologies such as a co-design process, market analysis and benchmarking, monitoring and co-building. These preliminary results highlight the need for respecting diversity of practices and communities through coordination and harmonization.

When the politician Roman Haider of the party Freiheitliche Partei Österreichs (FPÖ – Freedom Party of Austria) caused the interruption of a lecture about political extremism in an Austrian school in spring 2017, a heated debate erupted over the place of politics in school education. While Haider accused the lecturer of political propaganda, teachers, students and political opponents were upset about this seeming act of censorship. The controversy raises important questions over the aims and principles of civic education, which will continue to engage teachers and educationalists.