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    Bettelverbot einst oder heute?

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    „The past is a foreign country: they do things differently there”[1] – oder auch nicht. Vor über zweihundert Jahren, im Sommer 1819, ließ der damalige Gouverneur des Großherzogtums, Jean-Georges (Othon-Martin-Victorin-Zacharie) Willmar,[2] mit einem Rundschreiben (Circulaire) Instruktionen bezüglich Bettelei veröffentlichen.[3] Bettelei wurde damals als akutes, länderüberschreitendes Problem wahrgenommen, denn neue Grenzen durchzogen Europa. ..

    Efficient resource allocation and user association in NOMA-enabled vehicular-aided HetNets with high altitude platforms

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    peer reviewedThe increasing demand for massive connectivity and high data rates has made the efficient use of existing spectrum resources an increasingly challenging problem. Non-orthogonal multiple access (NOMA) is a potential solution for future heterogeneous networks (HetNets) due to its high capacity and spectrum efficiency. In this study, we analyze an uplink NOMA-enabled vehicular-aided HetNet, where multiple vehicular user equipment (VUEs) share the access link spectrum, and a high-altitude platform (HAP) communicates with roadside units (RSUs) through a backhaul communication link. We propose an improved algorithm for user association that selects VUEs for HAPs based on channel coefficient ratios and terrestrial VUEs based on a caching-state backhaul communication link. The joint optimization problems aim to maximize a utility function that considers VUE transmission rates and cross-tier interference while meeting the constraints of backhaul transmission rates and QoS requirements of each VUE. The joint resource allocation optimization problem consists of three sub-problems: bandwidth allocation, user association, and transmission power allocation. We derive a closed-form solution for bandwidth allocation and solve the transmission power allocation sub-problem iteratively using Taylor expansion to transform a non-convex term into a convex one. Our proposed three-stage iterative algorithm for resource allocation integrates all three sub-problems and is shown to be effective through simulation results. Specifically, the results demonstrate that our solution achieves performance improvements over existing approaches. Index Terms-Non-orthogonal multiple access (NOMA) Heterogeneous networks (HetNets) Vehicular user equipment (VUE) High altitude platform (HAP) roadside units (RSUs)

    Expectation shock in education: utilising industry SERVQUAL to enhance student perception of STEAM and STEAM careers

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    peer reviewedIn industry, an expectation shock occurs when a customer has a post-experience perception that greatly exceeds their prior expectations. In our study, the customers are students and teachers. An expectation shock might occur when, for example, a student 'just did not expect to find STEAM so interesting'. The objective of this research was to determine how expectation shock might be used in schools to enhance student perception of STEAM and STEAM careers. It was found that expectation shock in the form of Hothousing intensive, collaborative workshops can be used in schools to greatly enhance student perception of STEAM and STEAM careers and give them experience of industry practise valuable for their future careers. Educational practice should focus on enhancing student or teacher perception rather than stated importance. It is essential to examine perception post-experience versus prior expectation to identify benefits (or not) from the activity

    Improving Logic Bomb Identification in Android Apps via Context-Aware Anomaly Detection

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    peer reviewedOne prominent tactic used to keep malicious behavior from being detected during dynamic test campaigns is logic bombs, where malicious operations are triggered only when specific conditions are satisfied. Defusing logic bombs remains an unsolved problem in the literature. In this work, we propose to investigate Suspicious Hidden Sensitive Operations (SHSOs) as a step toward triaging logic bombs. To that end, we develop a novel hybrid approach that combines static analysis and context-aware anomaly detection techniques to uncover SHSOs, which we predict as likely implementations of logic bombs. Concretely, DIFUZER++ identifies SHSO entry-points using an instrumentation engine and conducting an inter-procedural data-flow analysis. Subsequently, it extracts trigger-specific features to characterize SHSOs. To detect abnormal triggers, we utilize multiple One-Class SVM models, each trained on distinct sets of similar apps to more effectively capture normal behavior patterns. To assess the added value of the context-aware analysis, we compare DIFUZER++ against a baseline approach with no context (that we name DIFUZER). We show that the context-aware analysis leads to a significant improvement in both the precision and F1 score. Furthermore, the probability of successfully triaging logic bombs among SHSOs increases from 29.7% to 58.8%. All our artifacts are released to the community.U-AGR-7109 - C21/IS/16344458/REPROCESS/Klein (01/07/2022 - 30/06/2025) - KLEIN Jacque

    Revisiting Android App Categorization

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    peer reviewedNumerous tools rely on automatic categorization of Android apps as part of their methodology. However, incorrect categorization can lead to inaccurate outcomes, such as a malware detector wrongly flagging a benign app as malicious. One such example is the SlideIT Free Keyboard app, which has over 500000 downloads on Google Play. Despite being a "Keyboard" app, it is often wrongly categorized alongside "Language" apps due to the app's description focusing heavily on language support, resulting in incorrect analysis outcomes, including mislabeling it as a potential malware when it is actually a benign app. Hence, there is a need to improve the categorization of Android apps to benefit all the tools relying on it. In this paper, we present a comprehensive evaluation of existing Android app categorization approaches using our new ground-truth dataset. Our evaluation demonstrates the notable superiority of approaches that utilize app descriptions over those solely relying on data extracted from the APK file, while also leaving space for potential improvement in the former category. Thus, we propose two innovative approaches that effectively outperform the performance of existing methods in both description-based and APK-based methodologies. Finally, by employing our novel description-based approach, we have successfully demonstrated that adopting a higher-performing categorization method can significantly benefit tools reliant on app categorization, leading to an improvement in their overall performance. This highlights the significance of developing advanced and efficient app categorization methodologies for improved results in software engineering tasks

    What if Alexander the Great Had Conquered the New World? Non-synchronicity of Civilizations, Colonialism and Chronopathy according to Montaigne

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    editorial reviewedDans son chapitre « Des coches » (1588) – qui, significativement, traite aussi le sujet du mal des transports – Montaigne pourfend l’extermination de « millions de peuples » par ses contemporains européens. À cette occasion, il présente l’uchronie d’une colonisation exemplaire et féconde du Nouveau Monde, près de deux mille ans plus tôt, par Alexandre le Grand. Diagnostiquant le problème de la « non-contemporanéité » (Ernst Bloch) des civilisations, l’auteur des Essais est à la fois l’héritier d’une tradition antique d’exempla ficta mettant en scène le conquérant macédonien et le précurseur d’une veine politique de l’uchronie toujours vivace au XXIe siècle (Laurent Binet). Attentif aux rythmes des civilisations comme à ceux des êtres vivants, il ne remet pas en cause la nécessité de la colonisation, mais ses modalités, formulant, grâce à l’uchronie, une pensée du métissage qui pourrait être qualifiée d’altercolonialiste. Il nous permet également par là de discuter et de réévaluer les notions anthropologiques d’« allochronisme » et de « co-temporalité » (Johannes Fabian). Une telle entreprise souffre toutefois d’inévitables apories : c’est qu’au fond elle ne relève ni d’une démarche contrefactuelle savante ni d’un appel à l’action, mais plutôt, pour reprendre à la science-fiction un topos des voyages dans le temps (le voyageur y souffrant fréquemment de divers symptômes désagréables), de l’expression d’un malaise temporel (temporal sickness) : cette chronopathie se manifeste par l’écœurement et la nausée. L’uchronie vient ainsi souligner tout ce qui fait vomir dans le présent : sa puissance politique et polémique tient moins à l’exercice de l’imagination qu’à l’expression de l’indignation et du dégoût.16. Peace, justice and strong institution

    Derivation of Rytov Variance for Jet Engine-Induced Turbulence

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    peer reviewedAbstract In this study, we analytically derived the Rytov variance and scintillation index value of turbulence caused by jet engines. In addition, we analyzed the variation characteristics of the Rytov variance and scintillation index values numerically depending on the variations in turbulence strength, experimental data, and wavelength. We observe that Rytov variance reaches up to high values due to the strong turbulence resulting from high refractive index fluctuations. This result brings high-intensity fluctuations regardless of the anisotropy of the turbulence. Rytov variance is directly proportional to turbulence strength. We present scintillation index curves considering the aperture averaged case. We plot our results considering the variations in the operating wavelength, turbulence strength, and the scaling parameter. According to our results, we think that it will be useful for a system such as directed infrared countermeasure (DIRCM), which is highly sensitive and should be exposed to minimum turbulence in the field of use. Since DIRCMs transmit codes to paralyze the missile's seeker, intensity fluctuations play a vital role during this transmission. It could reduce the performance of these systems when intensity fluctuations are high


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