272 research outputs found
3D EDX microanalysis by FIB-SEM: Elemental quantification enhancement
Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 - August 2, 201
Multivariate Statistical Analysis tool for the interpretation and the quantification of hyperspectral data: application to 3D EDX/FIB images
Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 - August 2, 201
Focused Ion Beam Nano-Tomography Using Different Detectors
Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7-August 11, 201
Intrinsic Geometry of a Null Hypersurface
We apply Cartan's method of equivalence to construct invariants of a given
null hypersurface in a Lorentzian space-time. This enables us to fully classify
the internal geometry of such surfaces and hence solve the local equivalence
problem for null hypersurface structures in 4-dimensional Lorentzian
space-times
Impact of processed earwigs and their faeces on the aroma and taste of 'Chasselas' and 'Pinot Noir' wines
The abundance of the European earwig Forficula auricularia L. (Dermaptera, Forficulidae) in European vineyards increased considerably over the last few years. Although earwigs are omnivorous predators that prey on viticultural pests such as grape moths, they are also known to erode berries and to transfer fungal spores. Moreover, they are suspected to affect the human perception of wines both directly by their processing with the grapes and indirectly by the contamination of grape clusters with their faeces. In this study we artificially contaminated grapes with F. auricularia adults and/or their faeces and determined the impact on aroma and taste of white 'Chasselas' and red 'Pinot noir' wines. Whereas the addition of five living adults/kg grapes affected the olfactory sensation of 'Chasselas' wines only marginally, 0.6 gram of earwig faeces/kg grapes had a strong effect on colour, aroma and the general appreciation of 'Chasselas' wines. Faeces-contaminated wines were less fruity and less floral, the aroma was described as faecal and they were judged to be of lower quality. The contamination of 'Pinot noir' grapes with four different densities of living earwig adults (e.g. 0, 5, 10 and 20 individuals/kg grapes) showed that only wines contaminated with more than 10 earwigs/kg grapes smelled and tasted significantly different than the uncontaminated control wine. Earwig-contaminated 'Pinot noir' wines were judged to be of lower quality. The descriptors âanimalâ, âreductiveâ, âvegetalâ, âacidicâ, âbitterâ and âtannicâ characterised their sensory perception. In conclusion, our results show that there is a real risk of wine contamination by F. auricularia. In particular, earwig faeces and earwig adults at densities above a threshold of 5 to 10 individuals/kg grapes have the potential to reduce the quality of wines. The evolution of earwig populations in vineyards should therefore be monitored carefully in order to anticipate problems during vinification.
Dr. Martin Hillenbrand to Receive University of Dayton Distinguished Alumnus Award
News release announcing the University of Dayton will Award Assistant Secretary of State for European Affairs, Dr. Martin Hillenbrand, with the Distinguished Alumnus Award
Nonlinearity Compensation in a Multi-DoF Shoulder Sensing Exosuit for Real-Time Teleoperation
The compliant nature of soft wearable robots makes them ideal for complex
multiple degrees of freedom (DoF) joints, but also introduce additional
structural nonlinearities. Intuitive control of these wearable robots requires
robust sensing to overcome the inherent nonlinearities. This paper presents a
joint kinematics estimator for a bio-inspired multi-DoF shoulder exosuit
capable of compensating the encountered nonlinearities. To overcome the
nonlinearities and hysteresis inherent to the soft and compliant nature of the
suit, we developed a deep learning-based method to map the sensor data to the
joint space. The experimental results show that the new learning-based
framework outperforms recent state-of-the-art methods by a large margin while
achieving 12ms inference time using only a GPU-based edge-computing device. The
effectiveness of our combined exosuit and learning framework is demonstrated
through real-time teleoperation with a simulated NAO humanoid robot.Comment: 8 pages, 7 figures, 3 tables. Accepted to be published in IEEE
RoboSoft 202
Dissociating Variability and Effort as Determinants of Coordination
When coordinating movements, the nervous system often has to decide how to distribute work across a number of redundant effectors. Here, we show that humans solve this problem by trying to minimize both the variability of motor output and the effort involved. In previous studies that investigated the temporal shape of movements, these two selective pressures, despite having very different theoretical implications, could not be distinguished; because noise in the motor system increases with the motor commands, minimization of effort or variability leads to very similar predictions. When multiple effectors with different noise and effort characteristics have to be combined, however, these two cost terms can be dissociated. Here, we measure the importance of variability and effort in coordination by studying how humans share force production between two fingers. To capture variability, we identified the coefficient of variation of the index and little fingers. For effort, we used the sum of squared forces and the sum of squared forces normalized by the maximum strength of each effector. These terms were then used to predict the optimal force distribution for a task in which participants had to produce a target total force of 4â16 N, by pressing onto two isometric transducers using different combinations of fingers. By comparing the predicted distribution across fingers to the actual distribution chosen by participants, we were able to estimate the relative importance of variability and effort of 1â¶7, with the unnormalized effort being most important. Our results indicate that the nervous system uses multi-effector redundancy to minimize both the variability of the produced output and effort, although effort costs clearly outweighed variability costs
3D EDX Microanalysis by FIB-SEM: Enhancement of Elemental Quantification
Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7-August 11, 201
Nonlinear Evolution Equations Invariant Under Schroedinger Group in three-dimensional Space-time
A classification of all possible realizations of the Galilei,
Galilei-similitude and Schroedinger Lie algebras in three-dimensional
space-time in terms of vector fields under the action of the group of local
diffeomorphisms of the space \R^3\times\C is presented. Using this result a
variety of general second order evolution equations invariant under the
corresponding groups are constructed and their physical significance are
discussed
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