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Investigating the Microquasar SS 433 and the PeVatron Candidate MGRO J1908+06 with a Novel Extended Source Analysis Method
No full textDie Herkunft galaktischer sehr hochenergetischer und ultrahochenergetischer kosmischer Strahlung bleibt rätselhaft, aber Studien weisen auf zahlreiche galaktische Quellen namens PeVatrons hin, die Teilchen auf Petaelektronenvolt-Energien beschleunigen können, darunter Pulsarwindnebel, Supernovareste und Mikroquasare. Die Untersuchung der Gammastrahlung bei Giga- und Teraelektronenvolt-Energien bietet entscheidende Einblicke in ihre Eigenschaften und erweitert unser Verständnis hochenergetischer astrophysikalischer Phänomene.
Diese Arbeit analysiert Daten des VERITAS-Gammastrahlenobservatoriums, bestehend aus vier 12-Meter-Tscherenkow-Teleskopen in Arizona, um ein umfassendes Verständnis von zwei galaktischen Quellen zu liefern: MGRO J1908+06, ein potenzieller PeVatron-Kandidat, und SS 433, ein Mikroquasar. MGRO J1908+06 wurde bereits in verschiedenen Wellenlängen untersucht, wobei mehrere potenzielle Ursprünge der Strahlung identifiziert wurden. Diese Arbeit führt eine umfassende Neuuntersuchung seiner ausgedehnten Gammastrahlenemissionen durch, um präzisere Abschätzungen des Gammastrahlenflusses zu liefern und frühere Ergebnisse zu aktualisieren. Die Untersuchung deutet auf einen möglichen Ursprung der Gammastrahlung sowohl aus einem Relikt eines Pulsar-Windnebels als auch aus einem neuen Pulsar-Windnebel im Feld von MGRO J1908+06 hin.
Erstmals wird in den VERITAS-Daten eine signifikante Gammastrahlenemission von SS 433 festgestellt. Es werden die Gammastrahlen der Jets bei größeren Abständen und ihre Morphologie untersucht, und TeV-Spektren werden generiert. Modelle zeigen einen leptonischen Ursprung dieser Emissionen, ohne dass eine signifikante Gammastrahlenemission in der Nähe des Schwarzen Lochs oder Anzeichen für Variabilität beobachtet werden.
Ausblickend präsentiert die Arbeit Untersuchungen zur Optimierung der Eigenschaften des Cherenkov-Teleskop-Array Observatoriums, mit Fokus auf die Platzierung von Illuminatoren und Abschattungseffekte zwischen Teleskopen.The origins of galactic very-high energy and ultra-high energy cosmic rays remain elusive. Recent studies propose the existence of PeVatrons, galactic sources capable of accelerating particles to Petaelectronvolt energies, such as pulsar wind nebulae, supernova remnants, and micro-quasars. Exploring gamma-ray emission at Giga- and Teraelectronvolt energies offers crucial insights into their properties, enriching our understanding of high-energy astrophysical phenomena.
This thesis focuses on analysing data from the VERITAS gamma-ray observatory, comprising four 12-meter imaging atmospheric Cherenkov telescopes in Arizona. Employing 3D maximum-likelihood analysis methods, the study aims to provide a comprehensive understanding of two extended galactic sources: MGRO J1908+06, a potential PeVatron candidate, and SS 433, a microquasar.
MGRO J1908+06, though unidentified, has been scrutinized across various wavelengths, with several potential counterparts identified previously. This thesis undertakes a re-analysis of its extended gamma-ray emission, leveraging updated analysis methods and recent VERITAS observations. The improved analysis method provides a more accurate estimate of the gamma-ray flux, revising prior VERITAS flux estimates and suggesting a scenario involving both relic and new pulsar wind nebulae.
Regarding SS 433, significant gamma-ray emission is detected in VERITAS data for the first time. The morphological properties of the gamma-ray emission regions seen at larger distances along the jets are examined, and their TeV spectra are constructed. Modelling supports a leptonic origin of these emissions, with no significant gamma-ray emission observed near the black hole or any indication of variability. Looking ahead, the thesis presents investigations aimed at optimizing the characteristics of the Cherenkov Telescope Array Observatory, focusing on illuminator placement and mutual shadowing effects to enhance telescope positioning within the array
Implementing machine learning techniques for continuous emotion prediction from uniformly segmented voice recordings
Get PDFEmotional recognition from audio recordings is a rapidly advancing field, with significant implications for artificial intelligence and human-computer interaction. This study introduces a novel method for detecting emotions from short, 1.5 s audio samples, aiming to improve accuracy and efficiency in emotion recognition technologies.MethodsWe utilized 1,510 unique audio samples from two databases in German and English to train our models. We extracted various features for emotion prediction, employing Deep Neural Networks (DNN) for general feature analysis, Convolutional Neural Networks (CNN) for spectrogram analysis, and a hybrid model combining both approaches (C-DNN). The study addressed challenges associated with dataset heterogeneity, language differences, and the complexities of audio sample trimming.ResultsOur models demonstrated accuracy significantly surpassing random guessing, aligning closely with human evaluative benchmarks. This indicates the effectiveness of our approach in recognizing emotional states from brief audio clips.DiscussionDespite the challenges of integrating diverse datasets and managing short audio samples, our findings suggest considerable potential for this methodology in real-time emotion detection from continuous speech. This could contribute to improving the emotional intelligence of AI and its applications in various areas.Peer Reviewe
A Comprehensive Manual for Science Education
Get PDFThis paper introduces a novel analytical framework for dissecting and visualizing the fine-grained structure of scientific explanations through Element Maps. It delves into the methodological principles that transition from grammatical surface structures to deeper sense-making layers, such as propositions and individual elements. The manual outlines a two-part process designed to deconstruct written text into evaluable propositions which can then be refined into a granular elementary structure. This approach is illustrated through the analysis of an explanation for the day-night cycle, demonstrating the utility of Element Maps in capturing features like the complexity, coherence, and appropriateness of explanations as well as use of key terms. By representing the elementary structure in a network visualization, the study highlights how Element Maps can serve as a useful tool for educators and researchers in understanding the structure of an explanation which can be used to help learners write better scientific explanations. Beyond the analysis of explanations, the application of this method on scientific arguments is discussed. Examples and a glossary of grammatical terms support support science educators in using the presented approach
Mindful-Gratitude Practice Reduces Prejudice at High Levels of Collective Narcissism
Get PDFThis research tested the hypothesis that mindful-gratitude practice attenuates the robust association between collective narcissism and prejudice. In Study 1 (a between-subjects study using a nationally representative sample of 569 Polish adults; 313 female), 10 min of mindful-gratitude practice—compared to mindful-attention practice and control—did not decrease prejudice (anti-Semitism), but weakened the positive link between collective narcissism and prejudice. In Study 2 (a preregistered, randomized, controlled-trial study using a convenience sample of 219 Polish adults; 168 female), a 6-week mobile app supported training in daily mindful-gratitude practice decreased prejudice (anti-Semitism, sexism, homophobia, anti-immigrant sentiment) and its link with collective narcissism compared to a wait-list control. The hypothesis-consistent results emphasize the social relevance of mindful-gratitude practice, a time- and cost-effective intervention.Narodowe Centrum Nauki
https://doi.org/10.13039/501100004281Peer Reviewe
A diachronic account of entre-prefixation in French
No full textThe paper explores the origin and development of the [entre-V] construction in the history of French. By means of quantitative corpus data, it is shown that the [entre-V] construction, particularly in its reciprocal function, is productive in earlier stages of French and progressively disappears over time. We argue that this decrease in productivity is connected to the change in availability of the more abstract [pref-V] construction. While Old French still shows residual stages of Latin prefixation, this system dissolves in the history of French. As speakers have less access to the [pref-V] construction, this also engenders numerous changes in the constructional network of the [entre-V] construction
Energy infrastructures in divided cities
No full textWithin the rich literature on politically divided cities, infrastructure has rarely featured as a medium of urban contestation. Only transportation infrastructure has merited attention of late. This paper presents an in-depth investigation of energy infrastructures as instruments of separation, control and collaboration in three iconic divided cities: Berlin, Jerusalem and Nicosia. The purpose of the paper is threefold: 1) to identify the multiple ways in which geopolitical division and unification have manifested themselves in the cities’ electricity (and gas) supply systems; 2) to analyse the strategic responses of service providers, politicians and users to their divided and united energy systems over time and 3) to use the cases to generate insight into energy infrastructures as conduits of separation, control and collaboration in politically contested cities. The research approach is distinctive for being socio-material (exploring the politics and agency of infrastructures), relational (appreciating the co-shaping of cities and infrastructures) and historical (covering 75 years of shifting responses to division and unification). The findings from this long-term analysis challenge simplistic distinctions between separation, control and collaboration. They point, rather, to the co-existence and even hybridisation of these three strategies at any one time and place, as well as to the limitations facing ideal types, as expressed in our terminology ‘seductive separation’, ‘constrained control’ and ‘conditional collaboration’. The paper emphasises the need to see beyond and within a city to comprehend the contested geographies around energy in divided cities. It also highlights the politicised indeterminacy of infrastructures in volatile urban environments, countering popular images of them as bulwarks of stability
Social Influencers and Election Outcomes
No full textDo social influencers affect election outcomes? Social influencers can reach millions of people through social media platforms such as Facebook, YouTube, TikTok and Instagram. However, research on social influencers is scarce and it is unclear whether they can affect elections. I argue that social influencers can influence elections through their role as digital opinion leaders and their power to shape the public agenda. Empirically, this study leverages an event that occurred during the 2019 European election campaign. Eight days before the 2019 EP election, the social influencer Rezo published a video in which he severely attacks the christian democratic CDU/CSU which was watched by over 11.5 million users until the election. Based on a differences-in-differences design, it is shown that the video had a sizeable effect on the election resulting in considerable vote losses for the CDU/CSU. The results are important for the debate on electoral competition and social media.Peer Reviewe
Producing white urban Europe? A critical and reflexive reading of academic knowledge production on urban integration of migrants in Western European cities
No full textIn this paper, I review studies of urban integration as analyzed for two groups of mobile newcomers: those designated as “migrants”, that is, mostly marginalized cross-border movers from outside Europe, and mobile EU citizens in Western European cities. This critical and reflexive reading serves to highlight how academic knowledge production on the topic has (re-)produced an image of white urban Europe. While critics of the concept of immigrant integration have suggested that cities and neighborhoods are better sites in which to study migrant integration than the nation-state, the paper demonstrates that studies of urban integration tend to suffer from similar problems, including an ethnonationalist focus and an essentializing of (ethnic) groups. The comparison foregrounds how mobile EU citizens are implicitly thought of as white; their presence in the urban territory is rarely questioned and their practices rarely problematized. In contrast, those designated as migrants are researched with reference to integration, whereby integration means moving closer to white spaces. Thus, studies of the urban integration of migrants use an ethnic framing, while studies of mobile EU citizens focus on class and nationality. The paper thus illuminates how studies of urban integration rely on and reproduce an implicit assumption of whiteness as the norm, even in diverse urban spaces
Why and how they listen: on the (im)possibility of inclusion in the global governance of education
No full textInternational Organisations in the field of education face increasing demands for greater inclusivity by and of those affected by their work. IOs respond by carrying out various forms of consultations in order to maintain their legitimacy, which leads to tensions with the largely expert-driven, ‘technocratic’ mode of operation of most IOs and potentially disrupts their organisational coherence and identity. This paper examines how UNESCO and OECD navigate this tension in two recent landmark initiatives: UNESCO’s Futures of Education (2019–2022) and OECD’s Future of Education and Skills 2030 (2015-present). We argue that IOs favour ‘additive’ over ‘disruptive’ inclusion to maintain organisational coherence, raising questions about the possibility of ‘disruptive’ inclusion within global governance
Lobbying and Advocating for Library and Information Professionals
No full textThe publication of this work was supported by the Open Access Publication Fund of Humboldt-Universität zu Berlin.Libraries on the Agenda shows how to engage in lobbying and advocating for libraries. The book analyzes political elements of power, policy making and human values. Political decision makers from local communities up to the international level need to be convinced, why libraries need their support. This title has an international approach to advocacy and shows many international examples. It presents tips and tools for successful advocating