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In diesem Beitrag werden empirische Perspektiven auf die politische Bildungspraxis mit Erwachsenen in Zeiten von Angst und Unsicherheit diskutiert. Dabei liegt die Annahme zugrunde, dass politische Bildungsarbeit mit Erwachsenen unter widrigen Bedingungen geleistet werden muss. Dieser Standpunkt stützt sich einerseits auf den Fachdiskurs, Positionspapiere von Fachverbänden und Erfahrungsberichte, andererseits auf die Ergebnisse aus qualitativen Untersuchungen der Verfasserin und des Verfassers dieses Beitrags.
Unternehmen stehen unter dem stetigen Druck, innovativ zu sein. Das gelingt nur, wenn Mitarbeiterinnen und Mitarbeiter die neuen Ideen auch umsetzen. Gerade in Zeiten, in denen eine Innovation auf die nächste folgt, wird das aber immer schwieriger. Denn die Frequenz und die Erfolgsrate von Innovationen werden von der Belegschaft bewertet und bestimmen über das Engagement in nachfolgenden Innovationsprozessen.
In diesem Beitrag werden empirische Perspektiven auf die politische Bildungspraxis mit Erwachsenen in Zeiten von Angst und Unsicherheit diskutiert. Dabei liegt die Annahme zugrunde, dass politische Bildungsarbeit mit Erwachsenen unter widrigen Bedingungen geleistet werden muss. Dieser Standpunkt stützt sich einerseits auf den Fachdiskurs, Positionspapiere von Fachverbänden und Erfahrungsberichte, andererseits auf die Ergebnisse aus qualitativen Untersuchungen der Verfasserin und des Verfassers dieses Beitrags.
Right-wing populism challenges the societies in Europe. The rise of such movements and parties are a threat to peace and democracy in Germany. This article focuses the possibilities as well as the boundaries of political education under the current circumstances. To this end, it discusses theoretical explanations based on approaches in peace education, political didactics and social sciences to deal with right-wing populism in practice. (DIPF/Orig.).
„Politiker sind doch eh nicht unabhängig“ oder: Alltagshelden im Umgang mit Stammtischparolen
(2019)
Durch die voranschreitende Digitalisierung bieten sich neue Ansätze für Designs und Methoden in der Jugendforschung. Mit vielfältigen digitalen Möglichkeiten wachsen auch Chancen für inklusiv angelegte Befragungen. Dieser Beitrag fokussiert exemplarisch gehörlose bzw. hörbeeinträchtigte gebärdensprachige Jugendliche und stellt nach einem theoretischen und empirischen Überblick die Frage, ob und inwieweit diese heterogene Gruppe Jugendlicher durch in digitale Fragebögen implementierte Videos in Gebärdensprache profitieren kann. Anhand zweier kontrastiver Fallvignetten sollen Erfahrungen aus dem Projekt „Inklusive Methoden“ in Bezug auf Möglichkeiten, Voraussetzungen, Herausforderungen und Grenzen digitaler Befragungen mit Gebärdensprachvideos dargestellt und diskutiert werden.
This article revisits an analysis on (in)accuracies of time series averaging under dynamic time warping (dtw) conducted by Niennattrakul and Ratanamahatana [16]. They proposed a correctness-criterion for dtw-averages and postulated that dtw-averages can drift out of the cluster of time series to be averaged. They claimed that dtw-averages are inaccurate if they violate the correctness-criterion or suffer from the drift-out phenomenon. Furthermore, they conjectured that such inaccuracies are caused by the lack of triangle inequality. In this article, we show that a rectified version of the correctness-criterion is unsatisfiable and that the concept of drift-out is geometrically and operationally inconclusive. Satisfying the triangle inequality is insufficient to achieve correctness and unnecessary to overcome the drift-out phenomenon. We place the concept of drift-out on a principled basis and show that Fréchet means never drift out. The adjusted drift-out is a way to test to which extent an approximated dtw-average is coherent. Empirical results show that approximations obtained by the state-of-the-art averaging methods are incoherent in over a third of all cases.
The literature postulates that the dynamic time warping (dtw) distance can cope with temporal variations but stores and processes time series in a form as if the dtw-distance cannot cope with such variations. To address this inconsistency, we first show that the dtw-distance is not warping-invariant—despite its name and contrary to its characterization in some publications. The lack of warping-invariance contributes to the inconsistency mentioned above and to a strange behavior. To eliminate these peculiarities, we convert the dtw-distance to a warping-invariant semi-metric, called time-warp-invariant (twi) distance. Empirical results suggest that the error rates of the twi and dtw nearest-neighbor classifier are practically equivalent in a Bayesian sense. However, the twi-distance requires less storage and computation time than the dtw-distance for a broad range of problems. These results challenge the current practice of applying the dtw-distance in nearest-neighbor classification and suggest the proposed twi-distance as a more efficient and consistent option.
Averaging time series under dynamic time warping is an important tool for improving nearest-neighbor classifiers and formulating centroid-based clustering. The most promising approach poses time series averaging as the problem of minimizing a Fréchet function. Minimizing the Fréchet function is NP-hard and so far solved by several heuristics and inexact strategies. Our contributions are as follows: we first discuss some inaccuracies in the literature on exact mean computation in dynamic time warping spaces. Then we propose an exponential-time dynamic program for computing a global minimum of the Fréchet function. The proposed algorithm is useful for benchmarking and evaluating known heuristics. In addition, we present an exact polynomial-time algorithm for the special case of binary time series. Based on the proposed exponential-time dynamic program, we empirically study properties like uniqueness and length of a mean, which are of interest for devising better heuristics. Experimental evaluations indicate substantial deficits of state-of-the-art heuristics in terms of their output quality.
Purpose:
Because of the sharply growing interest worldwide of “hard” physical-mechanical robot systems for the execution of on-site construction tasks [i.e. single-task construction robots (STCRs)], the purpose of this study is to equip development projects with a systematic design-management system model that allows to integrate the different needs and aims of stakeholders.
Design/methodology/approach:
This paper proposes a STCR-technology management system (STCR-TMS) for the complete development cycle of STCR designs. The STCR-TMS is based on established principles from systems engineering and management and STCR-specific activities developed and tested by the authors as standalone elements in previous research work.
Findings:
The application of the STCR-TMS revealed the practicability of the method and the underlying concepts to provide practical guidance for the development process. Additional findings indicate that the method is sufficiently generic and flexible for application to different types of robots and indifferent world regions. This research has also shown that key activities need to be addressed to increase the practicability of the STCR-TMS.
Originality/value:
A unique characteristic of this method is the evolution with each utilization cycle. In addition, individual elements are interchangeable and can be adapted based on external circumstances. These properties allow the TMS to be applied to other fields in construction robotics. With the progression of the verification and validation of the method, know-how and certain elements can be fed into standardization activities (e.g. establishing a management system standard).
The Spoken Wikipedia Corpus collection: Harvesting, alignment and an application to hyperlistening
(2019)
Spoken corpora are important for speech research, but are expensive to create and do not necessarily reflect (read or spontaneous) speech ‘in the wild’. We report on our conversion of the preexisting and freely available Spoken Wikipedia into a speech resource. The Spoken Wikipedia project unites volunteer readers of Wikipedia articles. There are initiatives to create and sustain Spoken Wikipedia versions in many languages and hence the available data grows over time. Thousands of spoken articles are available to users who prefer a spoken over the written version. We turn these semi-structured collections into structured and time-aligned corpora, keeping the exact correspondence with the original hypertext as well as all available metadata. Thus, we make the Spoken Wikipedia accessible for sustainable research. We present our open-source software pipeline that downloads, extracts, normalizes and text–speech aligns the Spoken Wikipedia. Additional language versions can be exploited by adapting configuration files or extending the software if necessary for language peculiarities. We also present and analyze the resulting corpora for German, English, and Dutch, which presently total 1005 h and grow at an estimated 87 h per year. The corpora, together with our software, are available via http://islrn.org/resources/684-927-624-257-3/. As a prototype usage of the time-aligned corpus, we describe an experiment about the preferred modalities for interacting with information-rich read-out hypertext. We find alignments to help improve user experience and factual information access by enabling targeted interaction.
Handling tire models like Pacejka (Tire and Vehicle Dynamics, 3rd edn., Elsevier, Amsterdam, 2012) or TMeasy (Rill in Proc. of the XV Int. Symp. on Dynamic Problems of Mechanics, Buzios, RJ, Brazil, 2013) consider the contact patch as one coherent plane. As a consequence, the irregularities of a rough road profile must be approximated by an appropriate local road plane that serves as an effective road plane in order to calculate the geometric contact point and the corresponding contact velocities. The Pacejka/SWIFT tire model employs a road enveloping model that generates the effective height and slope by elliptical cams. TMeasy just uses four representative road points for that purpose. In addition, TMeasy replaces the geometric contact point by the static contact point and shifts it finally to the dynamic contact point that represents the point where the contact forces are applied. In doing so, a rather sophisticated but still simple contact calculation is possible. Simulations obtained with a virtual tire test rig and fully nonlinear three-dimensional multibody system models of a motor-scooter and a passenger car demonstrate the potential of this contact approach.
In modern manufacturing systems, milk run (MR) systems represent route-based, cyclic material-handling systems that are used widely and enable frequent deliveries of containerized parts in small lot sizes from a central storage area to multiple points of use on the factory floor. Usually, deliveries take place at predetermined, constant time intervals. As in real-world MR systems, the number of containers to deliver in each interval varies in the short term, peaks in the number of deliveries may lead to capacity bottlenecks and late deliveries. In this paper, we develop three alternative strategies to determine starting times of MR cycles in real-time based on the current number of delivery orders in the system aiming to better handle variations in the number of orders. We evaluate the three strategies for different system load scenarios with respect to delivery service levels, order lead times, systems utilization and necessary number of MR trains using a discrete-event simulation model.