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In this practical approach to distributed propulsion, the solar-powered manned motorglider icaré 2 has been used as a testbed for wingtip propulsion. The large wingspan and slow cruising speed of icaré 2 are highly suitable to assess the influence and potential of propellers at the wingtips for yaw control. The paper describes the work of a multidisciplinary team consisting of researchers, engineers, pilots and students, starting from the initial idea to use propellers at the wingtips of icaré 2 up to the actual flight test campaign. First, the design and development of the modular wingtip pods are described to house the propeller, electric motor, battery and further sensors and control systems. Furthermore, the modifications required for integrating the wingtip pods on the aircraft itself are outlined and the electrical and mechanical interfaces are defined and described. To obtain a permit to fly for the new configuration of the aircraft, several tests on system level of the wingtip pods needed to be conducted and documented for the authorities. Finally, the flight test campaigns carried out to date are outlined and described including the planning, lessons learned and results.

Abstract Digital agents with human-like characteristics have become ubiquitous in our society and are increasingly relevant in commercial applications. While some of them closely resemble humans in appearance (e.g., digital humans), they still lack many subtle social cues that are important for interacting with humans. Among them are the so-called microexpressions— facial expressions that are short, subtle, and involuntary. We investigate to what extent microexpressions in digital humans influence people's perceptions and decision-making in order to inform the practices of digital human's design. Our two experiments applied four types of microexpressions based on emotion type (happiness and anger) and intensity (normal and extreme). This paper is among the first to design and evaluate microexpressions with different intensity levels in digital humans. In particular, we leverage the possibilities of digitally (re)designing humans and human perception. These possibilities are feasible only in a digital environment, where it is possible to explore various microexpressions beyond real human beings' physical capabilities.

Commercializing data and data-related services has gained in importance in recent years. Driven by digitalization and the Internet-of-Things (IoT), companies and individuals continuously generate vast amounts of data. Data marketplaces have emerged to support these data providers in selling their data to different data consumers. However, data marketplaces face challenges in different data governance decision domains that inhibit their adoption. To get a better understanding of how data marketplaces counteract these challenges, this paper develops a taxonomy of data governance decision domains in data marketplaces. We used a taxonomy development method to inspect 13 data marketplaces from eight countries. The resulting taxonomy shows an overview of mechanisms concerning data quality, data security, data architecture, metadata, data lifecycle, data storage, and data pricing. We discuss common instantiation patterns, highlight gaps, and propose possible solutions. The taxonomy sets a foundation for further research and theory-building on data marketplaces. Practitioners can use the taxonomy to develop customized data governance strategies for data marketplaces.

Several studies have shown that video games may indicate or even develop intellectual and cognitive abilities. As intelligence is one of the most widely used predictors of job performance, video games could thus have potential for personnel assessment. However, few studies have investigated whether and how virtual reality (VR) games can be used to make inferences about intelligence, even though companies increasingly use VR technology to recruit candidates. This proof-of-concept study contributes to bridging this gap between research and practice. Under controlled laboratory conditions, 103 participants played the commercial VR game Job Simulator and took the short version of the intelligence test BIS-4. Correlation and regression analysis reveal that, on average, participants who completed the game more quickly than others had higher levels of general intelligence and processing capacity, suggesting that VR games may provide useful supplementary tools in the prediction of job performance. Still, our results also indicate that game-based assessments have limitations that deserve researchers’ attention, which lead us to discuss directions for future research.

Clustering offers significant insights in data analysis. Density-based algorithms have emerged as flexible and efficient techniques, able to discover high-quality and potentially irregularly shaped clusters. Here, we present scalable density-based clustering algorithms using random projections. Our clustering methodology achieves a speedup of two orders of magnitude compared with equivalent state-of-art density-based techniques, while offering analytical guarantees on the clustering quality in Euclidean space. Moreover, it does not introduce difficult to set parameters. We provide a comprehensive analysis of our algorithms and comparison with existing density-based algorithms.

Today an efficient warehouse and inventory management of spare parts for production machinery is essential for service organizations. Optimal strategies in procurement, stocking and supply play an important role for serviceability in spare parts management. In this context, individual item criticality should be considered, which describes how crucial a spare part is. This paper presents a three-dimensional classification approach for spare parts regarding a cross-plant central warehouse strategy of a service network. The approach uses two dimensions to estimate value and predictability of spare parts with aid of an ABC and XYZ analysis. The third dimension VED analyses a multi-criteria criticality classification and six feasible criteria are identified to describe item criticality. The methodology of the analysis is based on a decision tree, which represents the defined criteria by nodes. In addition, the analytic hierarchy process is used to solve the multi-criteria decision problems at the different nodes of the decision tree. The approach is developed in a research project and evaluation of spare parts is performed based on real inventory and transaction data in cooperation with an industrial company. As a result 15,000 out of 50,000 items could be classified as suitable for central warehousing.

Following the success of the inaugural games, the Microbial Olympics return with a new series of events and microbial competitors. The games may have moved to a new hosting venue, but the dedication to training, fitness, competition (and yes, education and humour) lives on.

Recent studies in tribology aim at the development of techniques to improve the microscopic geometry of the functional surface because of their ability to optimize the frictional behaviour. A deterministic surface microtexturing is a possibility to influence the lubrication regime, thus, adjusting friction coefficient and wear. In this study a model based on the equations of hydrodynamic lubrication of a linear wedge bearing was developed to explain the friction behaviour of oil lubricated, textured steel/sapphire pairs sliding unidirectionally with velocities up to 10 m/s. The model explained why, comparing textures with different channel widths, increasing lubrication films caused decreasing coefficient of friction although the model equations were derived from hydrodynamic theory. With the microscopic geometry as the reason for the unusual behaviour a further understanding of the mechanisms of crossed microchannels was gained.

Die Investitions- und Finanzierungsplanung bildet einen Grundpfeiler der betrieblichen Finanzwirtschaft. Haufig wird die theoretisch gegebene Methodenvielfalt aber lediglich auf Verfahren reduziert, welche die Unvollkommenheit des Kapitalmarkts ignorieren und die unsicheren Zahlungsstrome der Investitionsobjekte durch Risikozuschlage verdichten. Die simultane Investitions- und Finanzierungsplanungssimulation (SIPS) wahlt den entgegengesetzten Ansatz. Sie berucksichtigt explizit die Kapitalmarktunvollkommenheit und legt die mehrdeutigen Zahlungsstrome offen, so das als Ergebnis eine Bandbreite uber die Zielgrose und die Entscheidungsvariablen in Abhangigkeit von Zielsetzung und Entscheidungsfeld des Unternehmers resultiert.

Mould inserts made of low alloyed tool steel and cemented carbide were tested using a laboratory tribometer simulating micro powder injection moulding (μPIM) to characterize the influence of surface condition due to different machining (micro milling or electrical discharge machining) and finishing (ultrasonic wet peening or abrasive micro peening) processes on wear in contact with ceramic feedstocks of different composition. Results show that abrasive micro peening is a suitable finishing process to ensure an excellent wear resistance of EDM processed mould inserts made from ultrafine cemented carbide even in contact with alumina feedstock of high abrasiveness. Ultrasonic wet peening on the other hand allows effective deburring and smoothing of relatively soft steel surfaces after micro milling.

We present a novel distributed algorithm for the maximal independent set problem (This is an extended journal version of Schneider and Wattenhofer in Twenty-seventh annual ACM SIGACT-SIGOPS symposium on principles of distributed computing, 2008). On bounded-independence graphs our deterministic algorithm finishes in O(log* n) time, n being the number of nodes. In light of Linial’s Ω(log* n) lower bound our algorithm is asymptotically optimal. Furthermore, it solves the connected dominating set problem for unit disk graphs in O(log* n) time, exponentially faster than the state-of-the-art algorithm. With a new extension our algorithm also computes a δ + 1 coloring and a maximal matching in O(log* n) time, where δ is the maximum degree of the graph.

Manufacturing of ceramic and metallic micro components in micro powder injection moulding (μPIM) requires mould inserts offering high wear resistance and a sufficient demoulding behaviour. Within the frame of this research μPIM mould inserts made from low and high alloyed tool steel were structured by micro milling and finished by micro peening and ultrasonic wet peening. Influence of surface condition on wear and demoulding behaviour of the steels in μPIM with ceramic feedstock was characterized using a laboratory tribotester simulating powder injection moulding and a specially adapted static friction tester. Results indicate that performance of mould inserts in micro powder injection moulding depends not only on hardness, surface condition and homogeneity of the mould insert materials but also is strongly influenced by the characteristics of the feedstock, like composition of the binder or amount and hardness of the ceramic particles.

Currently for the design of micro components often no reliable material data is available. Therefore in the German Collaborative Research Centre (SFB) 499 [1] metallic and ceramic micro specimen that are manufactured by different micro moulding techniques as micro casting, slip casting or micro powder injection moulding are investigated with respect to their microstructure, mechanical and tribological properties. As metal was investigated a AuAgCu-alloy named Stabilor G and as ceramic was investigated ZrO2. Additionally the wear behaviour of mould inserts made of different materials as X38CrMoV5–1, Ni and Cu63Zn37 and the modifications of near surface microstructures due to micro milling in X38CrMoV5–1 in different heat treatment states are presented.

Commercially available, slightly porous monolithic alumina was modified using CO2-laser irradiation by embedding zirconia, titanium nitride and tungsten carbide. The thickness of the modified surface layers was 550 μm after laser treatment and the composition of the multiphase microstructures depended on the laser process and the additives used. Tribological tests were carried out on the ceramics using a laboratory tribometer in unlubricated, oscillating sliding contact at room temperature against alumina balls. The wear mechanisms during running-in were analysed by short-time tests and studies of the worn surfaces by SEM.

Die Behandlungsstrategie bei distalen Humerusfrakturen ist allgemein akzeptiert und hat sich in den letzten 15 Jahren nicht wesentlich verandert. Das erklarte Ziel bleiben eine anatomische Reposition und stabile Osteosynthese mit fruhfunktioneller Nachbehandlung. Bei kompletten intraartikularen Frakturen ist der Zugang uber eine Olekranonosteotomie notwendig. Unsere eigenen Ergebnisse mit nur 63% guten und sehr guten Resultaten nach B- und C-Verletzungen (34 Patienten) sind nicht befriedigend. Trotz weltweit anerkannter standardisierter Operationstechnik stellt die Verbesserung der klinischen Resultate eine bleibende Herausforderung dar und ist bei zurzeit fehlenden Neuerungen in der operativen Technik u. a. nur durch die Vermeidung individueller Fehler zu erreichen.

Gaseous nitric acid (HNO3) and hydrogene fluoride (HF) have been measured in the winter Arctic stratosphere using balloon- and aircraft-based Ion Molecule Reaction Mass Spectrometry (IMRMS) instruments. Strong HNO3 perturbations were found in 1993 and 1995 which may indicate nitrification around 11-13 km and denitrification around 20 km altitude. Most likely these perturbations were caused by sedimentation of HNO3 containing aerosols followed by aerosol evaporation at lower altitudes.

Objective and Design: Thalidomide is very effective in the treatment of idiopathic aphthous stomatitis, characterized by recurrent focal intramucosal leukocytic vasculitis. The mode of action of thalidomide in this clinical entity may include inhibition of the extravasation of leukocytes. Therefore, we studied the effect of thalidomide on different steps of leukocyte migration by intravital microscopy.¶Material: Male Syrian golden hamsters were used.¶Treatment: Leukocyte migration in buccal mucosa of the hamster cheek pouch was elicited by the local application of lipopolysaccharide (LPS, 20 μg/ml) or murine tumor necrosis factor-α (muTNF-α, 10 ng/ml). (+)-Thalidomide (20–200 mg/kg i.p.) was administered 60 min before the local application of LPS or muTNF-α. Dexamethasone (2 × 1.0–10 mg/kg i.p.) was administered 18 h and 60 min before topical LPS application.¶Methods: The numbers of rolling, firmly adherent and migrating leukocytes were estimated by intravital microscopy up to 165 min after the topical applications of LPS or muTNF-α and evaluated by an interactive image analysis software.¶Results: Thalidomide (20–200 mg/kg i.p.) dose-dependently inhibited LPS-stimulated perivenular leukocyte migration by up to 87 ± 5% and muTNF-α-induced leukocyte migration by up to 78 ± 4%. Dexamethasone (2 ± 1.0–10 mg/kg i.p.) inhibited LPS-stimulated leukocyte migration by up to 85 ± 13%. (+)-Thalidomide (200 mg/kg i.p.) inhibited LPS-stimulated rolling by 80 ± 5% and reduced the number of firmly adherent leukocytes by about 40%. Dexamethasone (2 × 10 mg/kg i.p.) did not reduce the number of rolling leukocytes but inhibited leukocyte adherence by 72 ± 9%.¶Conclusions: These results show that (+)-thalidomide predominantly inhibits leukocyte rolling and thus differs from the glucocorticoid dexamethasone. The inhibition of LPS- or muTNF-α-induced leukocyte extravasation by thalidomide may account for some of its clinical activities.

In situ aircraft measurements of O3, CO,HNO3, and aerosol particles are presented,performed over the North Sea region in the summerlower stratosphere during the STREAM II campaign(Stratosphere Troposphere Experiments by AircraftMeasurements) in July 1994. Occasionally, high COconcentrations of 200-300 pbbv were measured in thelowermost stratosphere, together with relatively highHNO3 concentrations up to 1.6 ppbv. The particlenumber concentration (at standard pressure andtemperature) between 0.018-1 μm decreased acrossthe tropopause, from >1000 cm-3 in the uppertroposphere to

Laser induced surface modification has been used to fabricate conducting paths in ceramic substrates. For the purpose of process simulation and prediction of process parameters a finite element model has been developed to simulate the thermal behaviour of the substrate during laser surface interaction. The results of the model calculation have been verified experimentally for alumina and Cordierite substrates. Using this model the width and the depth of the fabricated lines could be predicted as a function of the laser power and velocity. The stresses due to thermal mismatch are estimated and identified as the likely reason for crack formation which reduces the functionality of the conducting paths. Further developments will consider different ceramic substrates such as PZT.

Reaction of octacarbonyldicobalt with LiC6H5 and subsequent treatment withEt 3OBF4 yields the cluster complex1. The expected complex2 is not obtained. Preparation, spectroscopic data and X-ray analysis are described.