Automatic Compensation of Workpiece Positioning Tolerances for Precise Laser

Precise laser welding plays a fundamental role in the production of high-tech goods, particularly in precision engineering. In this working field, precise adjustment and compensation of positioning tolerances of the parts to be welded with respect to the laser beam is of paramount importance. This procedure mostly requires tedious and error-prone manual adjustment, which additionally results in a sharp increase in production costs. We therefore developed a system which automates and thus accelerates this procedure significantly. To this end, the welding machine is equipped with a camera to acquire high resolution images of the parts to be welded. In addition, a software framework is developed which enables precise automatic position detection of these parts and adjusts the position of the welding contour correspondingly. As a result, the machine is rapidly prepared for welding, and it is much more flexible in adapting to unknown parts.This paper describes the entire concept of extending a conventional welding machine with means for image acquisition and position estimation. In addition to this description, the algorithms, the results of an evaluation of position estimation, and a final welding result are presented.

Sign segmentation with changepoint-modulated pseudo-labelling

The objective of this work is to find temporal boundaries between signs in continuous sign language. Motivated by the paucity of annotation available for this task, we propose a simple yet effective algorithm to improve segmentation performance on unlabelled signing footage from a domain of interest. We make the following contributions: (1) We motivate and introduce the task of source-free domain adaptation for sign language segmentation, in which labelled source data is available for an initial training phase, but is not available during adaptation. (2) We propose the Changepoint-Modulated Pseudo-Labelling (CMPL) algorithm to leverage cues from abrupt changes in motion-sensitive feature space to improve pseudo-labelling quality for adaptation. (3) We showcase the effectiveness of our approach for category-agnostic sign segmentation, transferring from the BSLCORPUS to the BSL-1K and RWTH-PHOENIX-Weather 2014 datasets, where we outperform the prior state of the art

When does the co-evolution of technology and science overturn into technoscience?

In this paper, the relations between science and technology, intervention and representation, the natural and the artificial are analysed on the background of the formation of modern science in the sixteenth century. Due to the fact that technique has been essential for modern science from its early beginning, modern science is characterised by a hybridisation of knowledge and intervention. The manipulation of nature in order to measure its properties has steadily increased until artificial things have been produced, such as laser beams, chemical compounds, elementary particles. Furthermore, the structural bracing of natural science, technological development, and industrial exploitation of nature go also back to the foundation of modern science. In order to strengthen the debate on technoscience against this background, the specific characteristics of technoscientific objects have to be clarified as have the specific characteristics of the social organisation of technoscience and its performance

Measurement of electrons from beauty-hadron decays in p-Pb collisions at root(NN)-N-S=5.02 TeV and Pb-Pb collisions at. root(NN)-N-S=2.76 TeV

The production of beauty hadrons was measured via semi-leptonic decays at mid-rapidity with the ALICE detector at the LHC in the transverse momentum interval 1<pT< 8 GeV/c in minimum-bias p-Pb collisions at sNN=5.02 TeV and in 1.3 < pT< 8 GeV/c in the 20% most central Pb-Pb collisions at sNN=2.76 TeV. The pp reference spectra at sNN=5.02 TeV and s=2.76 TeV, needed for the calculation of the nuclear modification factors RpPb and RPbPb, were obtained by a pQCD-driven scaling of the cross section of electrons from beauty-hadron decays measured at s=7 TeV. In the pT interval 3 < pT< 8 GeV/c, a suppression of the yield of electrons from beauty-hadron decays is observed in Pb-Pb compared to pp collisions. Towards lower pT, the RPbPb values increase with large systematic uncertainties. The RpPb is consistent with unity within systematic uncertainties and is well described by theoretical calculations that include cold nuclear matter effects in p-Pb collisions. The measured RpPb and these calculations indicate that cold nuclear matter effects are small at high transverse momentum also in Pb-Pb collisions. Therefore., the observed reduction of RPbPb below unity at high pT may be ascribed to an effect of the hot and dense medium formed in Pb-Pb collisions.[Figure not available: see fulltext.

Partial migration in roe deer

We studied partial migrations in the European roe deer (Capreolus capreolus), a species particularly suited for such a study, due to a wide distribution range and a high level of ecological plasticity and adaptation to human-induced environmental changes. We undertook a comparative analysis of a set of representative and contrasting European ecosystems (boreal, boreo-nemoral, alpine, central European and sub-Mediterranean), using a dataset of about 100 individuals tracked for at least 1 year, using GPS collars. One of the main finding was the relevance of intermediate migratory behaviour, i.e. many animals performed numerous trips back and forth between winter and summer areas before taking a final decision and stabilize their range. The migration process resulted highly inter- and intra-individually variable, where the “classic” partial migration alternatives (residents and sharp migrants) were only the extremes of a highly complex behavioural gradient. The probability of adopting a migratory strategy, and sharp migrations in particular, depended on modulation by external factors, and in particular by the presence of snow, and on costs of displacement. The behavioural migratory gradient seemed therefore an expression of ecological plasticity and quick adaptation to climatic variation. However, migration patterns differed a lot between males and females, providing evidence that sex-specific adaptations also play a role in shaping the movement tactics of roe dee