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Multifunctionality of Single‐Atom‐Thick 2D Magnetic Atoms in Nanolaminated M₂AX: Toward Permanent Magnets and Topological Properties
Get PDFM(ₙ₊₁)AXₙ (MAX) phases' nanolaminated ternary carbides or nitrides possess a unique crystal structure in which single‐atom‐thick A sublayers are interleaved by alternative stacking of an M(ₙ₊₁)Xₙ sublayer; these materials have been investigated as promising functional materials for industrial applications because of their laminated structure, as well as their metallic and ceramic properties. Based on high‐throughput density functional theory calculations, the stabilities and magnetic properties of M₂AX phases with A as magnetic elements (A = V, Cr, Mn, Fe, Co, and Ni) are investigated, aiming for designing new multifunctional magnets. The thermodynamical stabilities and the relative stability trend are first evaluated, resulting in 139 unreported metastable compounds, 39 of which are carbon‐based M₂AX compounds. After this, the mechanical stability and properties of metastable phases are analyzed. To determine the magnetic ground states of the newly predicted compounds, the magnetic exchange coupling parameters are further calculated, with the critical magnetic transition temperature evaluated based on the mean‐field theory. Particularly, several compounds such as Be₂FeN, Be₂CoN, and Fe₂FeN show high Curie temperature over 1000 K. Subsequently, the absolute value of magneto‐crystalline anisotropy energy (MAE) is calculated, and 20 compounds are found with a uniaxial anisotropy greater than 0.4 MJ m⁻³, which are potential gap magnets. Finally, the transport properties of the predicted ferromagnetic (FM) M₂AX compounds are evaluated. Notably, Y₂FeN possesses an anomalous Hall conductivity (AHC) and anomalous Nernst conductivity (ANC) (at 300 K) of around –1158 S cm⁻¹ and –4.59 A mK⁻¹. Particularly, when considering carbon doping in Ta₂FeN, the AHC and ANC are significantly enhanced, which also offers an effective tuning strategy for spintronics applications
Resource‐Efficient Anomaly Detection in Industrial Control Systems With Quantized Recurrent Variational Autoencoder
Get PDFThis work presents a novel solution for multivariate time series anomaly detection in industrial control systems (ICSs), specifically tailored for resource‐constrained environments. At its core, the quantized gated recurrent unit variational autoencoder (Q‐GRU‐VAE) architecture, a significant evolution from conventional methods, offers an extremely lightweight yet highly effective solution. By integrating gated recurrent units (GRUs) in place of long short‐term memory (LSTM) cells within a variational autoencoder (VAE) framework, and employing channel‐wise dynamic post‐training quantization (DPTQ), this model dramatically reduces hardware resource demands. The proposed solution exhibits performance on par with existing methods on the widely used secure water treatment (SWaT) and water distribution (WADI) benchmarks, while being tailored towards applications where computational resources are limited. This dual achievement of minimal resource consumption and preserved model efficacy paves the way for deploying advanced anomaly detection in resource‐constrained environments, marking a significant leap forward in enhancing the resilience and efficiency of ICSs
Evaluating Cultural Diversity in Text-to-Image Models
No full textText-To-Image (T2I) models have advanced significantly, leading to widespread global adoption. However,
these improvements are not equally reflected across cultures. To evaluate their cultural knowledge and assess
cross-cultural differences requires benchmarks. Current cultural benchmarks rely on simple text prompts
with English cultural concepts, overlooking the complexity of individuals, locations, and their semantic
and spatial interactions in realistic settings. To address this gap, we present a new T2I benchmark for
evaluating cultural knowledge, containing 1) a multilingual cultural concept dataset and 2) modular prompt
templates for generating compositional and complex prompts. Our dataset is built using a pipeline that
automatically extracts cultural concepts from Wikipedia, then refined through Large Language Models and
human assessment, covering 4 geographically and typologically diverse Geo-Cultures across 12 categories.
With 37 prompt templates, each containing 5 unique individuals and locations per category, our framework
enables comprehensive cultural evaluation of T2I models by generating up to 2.3 million unique text prompts.
We demonstrate that existing metrics fail to adequately assess the generation quality of cultural concepts by
comparing embedding-based models on aligned Wikipedia image-caption pairs and propose an automatic
metric using Visual Question Answering models to evaluate text-to-image alignment. Our analysis of three stateof-the-art T2I models reveal that they handle compositional prompts well but are limited in their generative
capabilities by their insufficient cultural knowledge. The assessment of their multilingual understanding,
achieved by translating prompts in the concept’s native language and evaluating cross-lingual consistency
reveals a bias in non-multilingual models towards Western languages. This underscores the need to improve
cross-cultural and multilingual capabilities in T2I models
Erziehung als Schlüssel zum Frieden
Get PDFIn der Geschichte der Pädagogik ist Hans-Jochen Gamm nicht wegzudenken. Geprägt von seinem Besuch in Auschwitz 1949 als polnischer Kriegsgefangener wurde er ein überzeugter Gegner des Faschismus. Mit seinen für die Zeit progressiven Ansichten eckte er einerseits an, brachte jedoch andererseits neuen Wind in die pädagogische Wissenschaft. Hans-Jochen Gamms Geburtstag jährte sich am 22. Januar zum hundertsten Mal
Autorschaft und Literarische Kommunikation in Fanfiction-Portalen : Harry Potter auf Fanfiktion.de
Get PDFDer Beitrag nimmt mit Metadatenanalysen die Veränderungen der Harry Potter-Fanfiction im ›Corona-Jahr‹ 2020 in den Blick. Dazu wurden sämtliche Texte, die in diesem Jahr auf Fanfiktion.de neu geschrieben oder fortgesetzt worden sind, als Korpus aufbereitetet. Im Mittelpunkt der Untersuchung steht die Frage, nach welchen Mustern und Kriterien Autorinnen und Autoren Aufmerksamkeit für ihre Texte erhalten. Mit Hilfe von Netzwerkmodellen kann den Ergebnissen deskriptiver Statistik, deren Mittelwerte leicht zu narrativen Unschärfen in der Interpretation führen, eine evidenzbasierte Analyse unterschiedlicher Kommunikationsrollen an die Seite gestellt werden. Topic Models und Sentiment-Analysen der Harry Potter-Romane sowie von Fanfiction und deren Reviews untermauern einen sozialen Trend zum restriktiven Umgang mit Negativität und negativer Kritik
Die Erfurt-Formation: Ein Beispiel zur Aquifergenese eines Kluftgrundwasserleiters
Get PDFBei der Beschreibung von Grundwasserleitern wird davon ausgegangen, dass diese in der Zeit statische Systeme darstellen, d. h. die Grundwasserleiter in Hinblick auf ihre Durchlässigkeit und Speichervermögen sowie auf ihren Lösungsinhalt zeitlich unveränderlich sind. Betrachtet man jedoch die landschaftsgeschichtliche Entwicklung eines Grundwasserleiters über geologische Zeiträume, so erkennt man, dass Grundwasserleiter dynamische Systeme darstellen, die zeitlichen Änderungen unterliegen. Dies wird am Beispiel der Erfurt-Formation in Nord-Württemberg gezeigt. Es lassen sich drei räumliche Bereiche identifizieren, die nebeneinanderliegen und unterschiedlichen Stadien der Aquifergenese entsprechen. Ausgehend von einem Geringleiter entwickelt sich ein gut durchlässiger und ergiebiger Grundwasserleiter, der mit Abnahme der Überdeckung und Verwitterung wieder zu einem Geringleiter wird. Das Beispiel zur Erfurt-Formation zeigt, dass hydrogeologisch verschiedene Bereiche, die heute räumlich nebeneinanderliegen, in einer Schichtstufenlandschaft aufeinanderfolgenden zeitlichen Stadien der Aquifergenese entsprechen. Dieses Modell zur Aquifergenese kann auch auf andere Grundwasserleiter übertragen werden und sollte bei der Charakterisierung eines Grundwasserleiters berücksichtigt werden
Psychotechnik, human factors, engineering psychology, Technikpsychologie — 100 years of interdisciplinary cooperation between engineering and human sciences
Get PDFThis special issue was edited by Joachim Vogt and Nina Gerber on the occasion of the 100th anniversary of the foundation of the Psychotechnik Institut at The Applied University of Technology in Darmstadt, Germany 1922. The institute was closed shortly after but the work continues in Darmstadt’s Institute of Ergonomics and Human Factors as well as Work and Engineering Psychology Research Group. We are proud to present a lot of high quality, state of the art, interdisciplinary research of psychologists and engineers, many of them with roots in Darmstadt. We open with two editorial articles. This first one by Vogt et al. describes how the field developed from experimental psychology and spread into many application fields. The second by Gerber et al. will build bridges to the following articles coming from colleagues all over Europe. We hope that this is a valuable contribution to the history and further development of our field
Extension of the system boundary of the Digital Twin onto the sensors of the Physical Twin through the introduction of redundant soft sensors
Get PDFThe benefit of Digital Twins depends to a large extent on the quality of the sensor data provided. In many cases, sensor failures are only detected late in operation which can lead to serious consequences. For this reason, one approach to reduce the resulting safety issues is to use redundant sensor systems that monitor the same measureand. However, due to the additional sensors required, this is associated with additional financial and design effort.
In this publication an alternative strategy is presented, which provides a redundant sensor system with the help of soft sensors. Soft sensors use already installed physical sensors to anticipate a new measured variable via algorithms. They are often used to avoid placing sensors in inaccessible locations, but are used here to perform redundant computation of already existing metrics. The sensor data of physical and soft sensors are used as input variables for a Digital Twin. Here, these are compared with each other and can be critically questioned by the twin itself. This makes it possible to extend the system boundary of the Digital Twin to the sensors themselves and provided input variables can be checked for their validity. This allows sensor failures to be detected at an early stage and consequential damage to be averted
Exploring interdependent privacy – Empirical insights into users' protection of others' privacy on online platforms
Get PDFRecent information privacy research has started to spark a debate about privacy infringements that happen not on an individual, but on a multi-party level. Here, a person's own information privacy is affected by the decisions of others – a phenomenon referred to as interdependent privacy. Building on the 3R Interdependent Privacy Protection Framework, we explore the underlying mechanisms of how and why interdependent privacy violations happen and how they can be remedied. Drawing on an online vignette experiment (N = 330), we investigate the efficacy of an interdependent privacy salience nudge and reveal that it can decrease the likelihood that users disclose others' personal information by 62%. Furthermore, we develop a novel measurement instrument and empirically validate that users' decision to disclose others' personal information to an online platform is formed via a serial mediation mechanism through users' realization of the data transfer, recognition of others' ownership, and respect for others' rights. We discuss important implications for both theory and practice
Utilizing APTV to investigate the dynamics of polydisperse suspension flows beyond the dilute regime : Applying APTV to polydisperse suspensions flows
Get PDFWe present a methodology that allows to measure the dynamics of polydisperse suspension flows by means of Astigmatism Particle Tracking Velocimetry (APTV). Measurements are successfully performed with tridisperse suspensions flows in a square duct of up to Φ=9.1% particle volume fraction. Using a refractive index matching technique, a small amount of the particles (Φ=0.08%) is labeled with fluorescent dye to be visible to the camera during the particle tracking procedure. Calibration measurements are performed for ten different particles diameters dp ranging from dp=15μm to dp=260μm. It is shown that Euclidean calibration curves of different dp overlap outside the focal planes, which induces ambiguities in a polydisperse APTV measurement. In the present approach, this ambiguity can be overcome utilizing the light intensity of a particle image which increases sharply with dp. In this way, extended Euclidean calibration curves can be generated for each particle group which are spatially separated through the light intensity which serves as an additional calibration parameter (Brockmann et al. in Exp Fluids 61(2):67, 2020). The extended Euclidean calibration allows to simultaneously differentiate particles of different sizes and determine their 3D location. This facilitates to investigate the migration behavior of mono- and tridisperse suspension flows which we demonstrate here for square duct flows with cross-sectional areas of 0.6×0.6mm² and 0.4×0.4 mm² at bulk Reynolds numbers of Reb≈20 and Reb≈40 for particle volume fractions of Φ=0.08% and Φ=9.1%. At Φ=0.08% and Reb=20, we observe particles to arrange themselves in a ring-like formation inside the capillary, henceforth referred to as Pseudo Segré Silberberg Annulus (PSSA), with no significant differences between mono- and polydisperse suspension particle distributions. At Φ=9.1%, particles in monodisperse suspensions scatter around the PSSA. This scattering decreases when dp increases or Reb increases from 20 to 40. Striking differences are observed in polydisperse suspensions. Large particles (60μm) scatter significantly less around the PSSA in the polydisperse case compared to a monodisperse suspension of the same overall volume fraction. In contrast, small and intermediate particles (30μm, 40μm) are repelled by larger particles resulting in regions of high concentration close to the channel walls which can be only observed in the polydisperse case