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The more severe the merrier: Severity of error consequences stimulates learning from error
No full textErrors at work can lead to learning but little is known about error attributes and person attributes that make learning more or less likely. This research tested the role of severity of error consequences (error attribute) and trait negative affectivity (person attribute) for learning from error. In two experimental vignette studies, participants responded to written error scenarios that typically happen to university students (Study 1, N = 216) or to employees at work (Study 2, N = 121). In support of the view that error consequences need to be severe enough to attract attention, severity of error consequences increased both affective learning (perceived utility of the error; Studies 1 and 2) and cognitive learning (correctly recalled error scenarios; Study 2). In both studies, trait negative affectivity was associated with decreased affective learning when error consequences were severe (interaction effect). The results suggest that some errors at work – at least errors with minor consequences – may not receive much attention and are easily forgotten. To fully exploit learning opportunities, organizations should give attention to all errors and take them seriously, irrespective of severity of immediate error consequences.
Practitioner points:
· Whether errors in organizations receive attention seems to depend on severity of error consequences, rather than on errors per se and their informational value.
· This implies that valuable learning opportunities of errors may be missed.
· To fully exploit learning opportunities, managers should encourage open communication and learning from error and avoid unproductive blaming.
· This particularly applies to dispositionally anxious individuals who may feel threatened by errors more easily and who may, in turn, respond defensively
Assessing dual use risks in AI research: necessity, challenges and mitigation strategies
No full textThis article argues that due to the difficulty in governing AI, it is essential to develop measures implemented early in the AI research process. The goal of dual use considerations is to create robust strategies that uphold AI’s integrity while protecting societal interests. The challenges of applying dual use frameworks to AI research are examined and dual use and dual use research of concern (DURC) are defined while highlighting the difficulties in balancing the technology’s benefits and risks. AI’s dual use potential is discussed, particularly in areas like NLP and LLMs, and the need for early consideration of dual use risks to ensure ethical and secure development is underscored. In the section on shared responsibilities in AI research and avenues for mitigation strategies the importance of early-stage risk assessments and ethical guidelines to mitigate misuse is emphasized, accentuating self-governance within scientific communities and structured measures like checklists and pre-registration to promote responsible research practices. The final section argues that research ethics committees play a crucial role in evaluating the dual use implications of AI technologies within the research pipeline. The need for tailored ethics review processes is articulated, drawing parallels with medical research ethics committees
On the Behavior of the Ethylene Glycol Components of Polydisperse Polyethylene Glycol PEG200
No full textMolecular dynamics (MD) simulations are reported for [polyethylene glycol (PEG)200], a polydisperse mixture of ethylene glycol oligomers with an average molar weight of 200 g·mol⁻¹. As a first step, available force fields for describing ethylene glycol oligomers were tested on how accurately they reproduced experimental properties. They were found to all fall short on either reproducing density, a static property, or the self-diffusion coefficient, a dynamic property. Discrepancies with the experimental data increased with the increasing size of the tested ethylene glycol oligomer. From the available force fields, the optimized potential for liquid simulation (OPLS) force field was used to further investigate which adjustments to the force field would improve the agreement of simulated physical properties with experimental ones. Two parameters were identified and adjusted, the (HO)–C–C–O proper dihedral potential and the polarity of the hydroxy group. The parameter adjustments depended on the size of the ethylene glycol oligomer. Next, PEG200 was simulated with the OPLS force field with and without modifications to inspect their effects on the simulation results. The modifications to the OPLS force field significantly decreased hydrogen bonding overall and increased the propensity of intramolecular hydrogen bond formation at the cost of intermolecular hydrogen bond formation. Moreover, some of the tri- and more so tetraethylene glycol formed intramolecular hydrogen bonds between the hydroxy end groups while still maintaining strong intramolecular interactions with the ether oxygen atoms. These observations allowed the interpretation of the obtained RDFs as well as structural properties such as the average end-to-end distances and the average radii of gyration. The MD simulations with and without the modifications showed no evidence of preferential association of like-oligomers to form clusters nor any evidence of long-range ordering such as a side-by-side stacking of ethylene glycol oligomers. Instead, the simulation results support the picture of PEG200 being a random mixture of its ethylene glycol oligomer components. Finally, additional MD simulations of a binary mixture of tri-and hexaethylene glycol with the same average molar weight as PEG200 revealed very similar structural and physical properties as for PEG200
Oberflächennahe geophysikalische Verfahren als Quelle: Magnetik, Geoelektrik und Elektromagnetik und ihre Validierung durch Sedimentkerne
No full textIn der Auenforschung eröffnet die geophysikalische Prospektion durch die räumliche Erfassung von Strukturen der fluvialen Architektur neue Möglichkeiten bei der Rekonstruktion von Schicht- und relativen Altersabfolgen von Sedimenten. Mithilfe bildgebender Verfahren wie der Magnetik, Gleichstromelektrik (ERT) sowie auch der elektromagnetischen Induktion (EMI) können beispielsweise die Verteilung von mächtigen Schluff-Ton-Ablagerungen (Auenlehme) und Überreste alter Flussläufe erfasst, oder Strukturabgrenzungen von Bauwerken durch die Erfassung von Unregelmäßigkeiten erkundet werden. Die Analyse von Kernbohrungen im Untersuchungsgebiet dient dabei als Validierung der geophysikalischen Ergebnisse
Fischers Moritz. Urbane Flussauen im Spiegel einer Nördlinger Stadtrechnung (1496/97)
No full textRechnungen gehören zur sogenannten pragmatischen Schriftlichkeit, also zum großen Bereich derjenigen Texte, die vor allem in pragmatischen Zusammenhängen (Alltag, Beruf, Verwaltung) entstehen, einem Zweck dienen, eine Handlung begleiten, dokumentieren oder Wissen bereitstellen. In diesem Beitrag wird danach gefragt, wie aus Rechnungen Wissen über historische Flussauen und die Gesellschaften, die in ihnen lebten, sowie den Interaktionen zwischen Fluss und Gesellschaft gewonnen werden kann. Dafür ist Quellenkritik in mehreren Schritten erforderlich. Zum einen muss die übliche historische Quellenkritik unter Beachtung der Quellengattung befolgt werden. Zum anderen ist eine besondere Sensibilität für die speziellen Aspekte erforderlich, die sich aus der spezifischen Fragerichtung ergeben. In besonderem Maß relevant ist eine mehrschrittige Quellenkritik für Texte, die auf den ersten Blick ein nüchternes Abbild der Wirklichkeit wiederzugeben scheinen, wie vor allem Rechnungslegungen (Quittungen, Rechnungen, Rechnungsbücher usw.). Diese Quellengattung ist Gegenstand einer hoch spezialisierten Forschung, die jedoch bisher kaum den in diesem Beitrag thematisierten Fragestellungen nachgegangen ist. In der Archäologie des Mittelalters ist generell bekannt, dass mittelalterliche Rechnungen zur Erschließung der materiellen Alltagskultur herangezogen werden können. Prinzipiell wird der Quellengattung in der umwelthistorischen Forschung ein Erkenntniswert beispielsweise für die Rekonstruktion von Veränderungen des historischen Fischbestandes in Langzeitperspektive oder von Ernährungsgewohnheiten mit Fisch zugeschrieben. Wie dies im Einzelnen erfolgen kann, wird am Beispiel eines Abschnitts aus den Stadtrechnungen der Reichsstadt Nördlingen 1496/97 über Einnahmen und Ausgaben im Zusammenhang mit Fischfang erläutert. Zentrale Fragen lauten: Welche quellenkundlichen Überlegungen sind dafür wichtig, was muss die erforderliche Quellenkritik beachten, wie kann eine kritische Edition und Interpretation einer Rechnung aussehen? Welche Probleme sind dabei zu berücksichtigen und welche Reichweite haben die erzielten Erkenntnisse
Urban Transportation in Latvian Novels or Why do you use a 19th-century horse-drawn cab when you have a 20th-century taxi?
No full textThe article explores the depiction of urban transportation in Latvian novels from the late 19th century to the mid-20th century, aiming to understand how these images reflect broader societal modernization and technological and social changes in an increasingly urbanized environment. The first part of the study explores the frequency and dissemination of mentions of urban vehicles in the novels. Two methods were used to identify relevant transport terms — Word2Vec and the Gemini 1.5 language model, comparing the results of both approaches. In the second part of the study, particular attention is given to the horse-drawn cab and the taxi, which illustrate economic development, societal modernization, and the growing disparity between different social strata. The study emphasizes that transportation is a practical means of mobility and a significant cultural and social symbol. The study uses the data set Corpus of Latvian Early Novels, which includes novels published between 1879 and 1940
Controlling Product Properties in Forming Processes Using Reinforcement Learning — An Application to V-Die Bending
Get PDFUncertainty is unavoidable in forming processes due to fluctuating properties in the semi-finished product, the tool system and the environment. For this reason, numerous scientists have addressed this issue by developing control approaches like self-optimizing machine tools or the control of product properties. Machine learning algorithms, in particular reinforcement learning (RL) methods, show promising results for controlling production processes in this way. In this paper, the application of RL is demonstrated on an industrially commonly used process, V-die bending. For this purpose, first a flexible tool system is developed that allows the bending angle to be adjusted continuously between 80 and 110°. The developed tool is initially simulated through an FEM model in order to create a sufficient database for the training of an RL agent for springback compensation. The pre-trained agent is then used to control the springback in the real process. To close the resulting sim-to-real gap, it is then retrained on the experimentally generated data. It is shown that the springback can be significantly reduced compared to the uncontrolled case in both the simulative and the experimental process
Unsicherheit in der Vibroakustik: Ein Überblick
No full textUnsicherheit ist allgegenwärtig und beeinflusst das Verständnis eines vibroakustischen Systems negativ. Auf der einen Seite führt Unsicherheit in der Modellbildung während der Entwurfsphase zur Streuung in der Vorhersage der vibroakustischen Eigenschaften des Systems. Auf der anderen Seite weicht die Systemdynamik während des Betriebs eines Systems aufgrund der unvollständigen Datenerfassung von der einer Prüfstandsmessung ab. Aufgrund steigender Anforderungen an die akustische Qualität von Produkten, z.B. akustikgerechte Gestaltung und Sound Design des Antriebstrangs einschließlich des Motorgeräuschs eines Fahrzeugs, soll ein besseres Verständnis der vibroakustischen Eigenschaften des Systems erreicht werden. Aus diesem Grund muss die zugrundeliegende Unsicherheit berücksichtigt werden. Unsicherheit kann beispielsweise durch probabilistische Methoden identifiziert und quantifiziert werden. Anhand der Betrachtung der Unsicherheit z.B. Wahrscheinlichkeitsverteilungen von vibroakustischen Zielgrößen kann das Systemverständnis verbessert werden. Weiterhin können zuverlässige Entscheidungen hinsichtlich der vibroakustischen Eigenschaften getroffen werden. Aufgrund dieses Potenzials wird die Betrachtung der Unsicherheit in der Vibroakustik im Rahmen dieses Beitrags vorgestellt. Dieser Beitrag fasst die wesentlichen Methoden und Begriffe zusammen und zeigt den Stand der Wissenschaft der Unsicherheit in der Vibroakustik auf
175. Geburtstag des Polarforschers Carl Weyprecht
No full textFast 130 Tage sonnenlose Finsternis, die dramatischen Eispressungen mit ihren knisternden, pfeifenden, knackenden, knirschenden und krachenden Geräuschvarianten: Eindrucksvoll beschreibt Carl Weyprecht die Wirkung des Eises während der Österreich-Ungarischen Nordpol-Expedition 1872 – 1874
Stability Analysis in Drilling Processes: Nonlinear Modeling and Prediction of Limit Cycle Whirling Oscillations
No full textThe high demand for increased productivity pushes machining processes to their stability limits. Drilling with twist drills is one of the most common machining operations. In drilling, two primary oscillation phenomena are observed, called whirling and chatter. This work focuses on the mathematical description of whirling oscillations to optimize the tool geometry and enhance the process understanding.
A nonlinear physical model with two degrees of freedom is developed to represent the drilling process. The model includes a mechanistic cutting force approach with experimentally determined cutting force coefficients, process damping at the main cutting edges, caused by the compressed workpiece material between the cutting edge and the newly cut workpiece surface, radial forces on the chisel edge in the center of rotation of the tool, and a model to describe the supporting effect of the margins against the borehole wall.
The numerical treatment of the resulting delay differential equations is discussed, with consideration given to the history of the evolution of the tool motion.
To derive the cutting force coefficients, thrust force and drilling torque measurements were conducted with a standard twist drill. Three-dimensional coefficients were derived from the two load signals by considering the limits of the frictional behavior in the cutting process. To validate the physical model, boreholes were drilled with different pre-drilled borehole radii using test tools with three different margin widths. Additionally, a method is proposed to reconstruct the tool vibrations from a measured borehole geometry, enabling the calculation of the whirling frequencies in a post-processing step.
By including the nonlinear bounding margin contact, the model accurately predicts limit cycles of whirling oscillations. It is demonstrated that whirling frequencies are crucial to obtain accurate margin contact conditions. The whirling frequencies and amplitudes are predicted with high accuracy for a wide range of process conditions. The model reveals a strong tendency of the borehole geometry to adapt to the twisted shape of the tool body. It also predicts the axial contact length of the margins, which was validated by friction marks on the used drilling tools. In addition, it reveals that the process damping at the main cutting edges is secondary to the process damping at the margin contact, regarding the whirling oscillations, given by the significantly smaller contact regions.
The validated model is then used to optimize the margin geometry. Measurements with prototypes featuring the optimized margin design showed a reduction in the diameter deviations of up to 60.3 % and an improvement of the borehole circularity by up to 47.8 % compared to the reference tool with standard geometry.
However, a limitation of the physical model was identified for the largest margin widths, where abrasion is strongly increased due to the excessive friction. Incorporating this effect into the model could enable predictions of the borehole diameter deviations. Furthermore, drill misalignment and grinding errors were not considered in the current model. The symmetry of the model prevents an asymmetric evolution of the borehole geometry. To predict the borehole straightness along the depth, it is suggested to implement such imperfections in future refinements of the model