Wide-Beamwidth Circular Polarized Antenna for Diversity Combining Applications

in Vasquez-Peralvo, Juan Andres; Merlano Duncan, Juan Carlos; Eappen, Geoffrey (Eds.) et al Global Communications Conference, Rio de Janeiro, 4 - 9 December 2022 (in press)

This paper presents the design, simulation, and manufacturing of a right-hand circularly polarized antenna working in the frequency band 17.7-20.2 GHz with a beamwidth of 42.4$^\circ$ and 5.4$^\circ$ for ... [more ▼]

This paper presents the design, simulation, and manufacturing of a right-hand circularly polarized antenna working in the frequency band 17.7-20.2 GHz with a beamwidth of 42.4$^\circ$ and 5.4$^\circ$ for the H-plane and E-plane, respectively. The presented antenna is part of a set of three antennas, two high-gain antennas, and, presented in this paper, a low directive antenna used for reception. The application we describe in this paper combines the radio-frequency signals obtained from the O3b satellite constellation, using three antennas to apply path diversity later to reconstruct the original signal. Moreover, using an antenna with a beamwidth in one plane allows receiving two satellite signals at the same time, increasing by 3 dB the overall gain. The wide-band capabilities of the antenna are obtained using aperture coupling. In particular, the circular polarization of the antenna is generated using a truncated corner square patch. Further, a metasurface is placed at the top to enhance the axial ratio. Importantly, the simulation results obtained using CST Microwave Studio show that the antenna has a reflection coefficient below -10 dB and an axial ratio below -3 dB in the intended frequency range. [less ▲]

The Rallye Platform: Mobile Location-based Serious Games for Digital Cultural Heritage

in Proceedings of the 25th International Conference on Human-Computer Interaction (HCI International) (in press)

DaMAT: A Data-driven Mutation Analysis Tool

in Proceedings of the 45th International Conference on Software Engineering (ICSE ’23) (in press)

We present DaMAT, a tool that implements data- driven mutation analysis. In contrast to traditional code-driven mutation analysis tools it mutates (i.e., modifies) the data ex- changed by components ... [more ▼]

We present DaMAT, a tool that implements data- driven mutation analysis. In contrast to traditional code-driven mutation analysis tools it mutates (i.e., modifies) the data ex- changed by components instead of the source of the software under test. Such an approach helps ensure that test suites appropriately exercise components interoperability — essential for safety-critical cyber-physical systems. A user-provided fault model drives the mutation process. We have successfully evalu- ated DaMAT on software controlling a microsatellite and a set of libraries used in deployed CubeSats. A demo video of DaMAT is available at https://youtu.be/s5M52xWCj84 [less ▲]

Triangular Intertwined Frequency Selective Surface

in Vasquez-Peralvo, Juan Andres; Merlano Duncan, Juan Carlos; Chatzinotas, Symeon (Eds.) et al International symposium on antennas and propagation (in press)

This paper presents a frequency selective surface design and simulation using intertwined triangular structures. It has been discovered that by using the proposed tessellated intertwined lattice, the ... [more ▼]

This paper presents a frequency selective surface design and simulation using intertwined triangular structures. It has been discovered that by using the proposed tessellated intertwined lattice, the reduction of the resonance frequency of a frequency selective surface can be improved by 22.58% compared with other triangular structures. Additionally, this structure is used as a MEFSS to improve the miniaturization of the structure and obtain a compact, angular stable band-pass filter. The simulations presented in this paper have been obtained using CST Microwave Studio. [less ▲]

Curves over finite fields and moduli spaces

in Curves over finite fields: past, present and future. (in press)

Advancing the Meet-in-the-Filter Technique: Applications to CHAM and KATAN

in Smith, Benjamin; Wu, Huapeng (Eds.) Selected Areas in Cryptography (in press)

Recently, Biryukov et al. presented a new technique for key recovery in differential cryptanalysis, called meet-in-the-filter (MiF). In this work, we develop theoretical and practical aspects of the ... [more ▼]

Recently, Biryukov et al. presented a new technique for key recovery in differential cryptanalysis, called meet-in-the-filter (MiF). In this work, we develop theoretical and practical aspects of the technique, which helps understanding and simplifies application. In particular, we show bounds on MiF complexity and conditions when the MiF-enhanced attack may reach them. We present a method based on trail counting which allows to estimate filtering strength of involved rounds and perform consequent complexity analysis with pen and paper, compared to the computer-aided approach of the original work. Furthermore, we show how MiF can be combined with plaintext structures for linear key schedules, allowing to increase the number of attacked rounds or to reduce the data complexity. We illustrate our methods on block cipher families CHAM and KATAN and show best-to-date single-key differential attacks for these ciphers. [less ▲]

A Methodology for Handling Data Movements by Anticipation: Position Paper

in Euro-Par 2018 Workshops (in press)

The enhanced capabilities of large scale parallel and distributed platforms produce a continuously increasing amount of data which have to be stored, exchanged and used by various tasks allocated on ... [more ▼]

The enhanced capabilities of large scale parallel and distributed platforms produce a continuously increasing amount of data which have to be stored, exchanged and used by various tasks allocated on different nodes of the system. The management of such a huge communication demand is crucial for reaching the best possible performance of the system. Meanwhile, we have to deal with more interferences as the trend is to use a single all-purpose interconnection network whatever the interconnect (tree-based hierarchies or topology-based heterarchies). There are two different types of communications, namely, the flows induced by data exchanges during the computations, and the flows related to Input/Output operations. We propose in this paper a general model for interference-aware scheduling, where explicit communications are replaced by external topological constraints. Specifically, the interferences of both communication types are reduced by adding geometric constraints on the allocation of tasks into machines. The proposed constraints reduce implicitly the data movements by restricting the set of possible allocations for each task. This methodology has been proved to be efficient in a recent study for a restricted interconnection network (a line/ring of processors which is an intermediate between a tree and higher dimensions grids/torus). The obtained results illustrated well the difficulty of the problem even on simple topologies, but also provided a pragmatic greedy solution, which was assessed to be efficient by simulations. We are currently extending this solution for more complex topologies. This work is a position paper which describes the methodology, it does not focus on the solving part. [less ▲]

Von Objekt- und Meta-Ebenen: Analyse der Softwareanforderungen computergestützter juristischer Entscheidungen

in Recht DIGITAL – 25 Jahre IRIS, Proceedings of the International Legal Informatics Symposium (IRIS 2022) (in press)

Die Interpretation und Anwendung von Gesetzestexten auf einem konkreten Lebenssachverhalt erfordert von menschlichen Experten ein hohes Maß an Wissen, Erfahrung und die Fähigkeit zahlreiche kontextuelle ... [more ▼]

Die Interpretation und Anwendung von Gesetzestexten auf einem konkreten Lebenssachverhalt erfordert von menschlichen Experten ein hohes Maß an Wissen, Erfahrung und die Fähigkeit zahlreiche kontextuelle Überlegungen anzustellen. Die Formalisierung und Automatisierung solch eines Prozesses in einem computergestützten Verfahren muss dies entsprechend reflektieren. Ausgehend von einer Fallstudie werden in dieser Arbeit erforderliche juridische Schritte der Rechtsanwendung identifiziert und verschiedenen Objekt- und Meta-Ebenen zugeordnet. Diese Zuordnung erlaubt eine abstrakte Analyse von Softwareanforderungen, die juristische Assistenzsysteme erfüllen müssen, um bei juristischen Fallentscheidungen unterstützen zu können. [less ▲]

Le quotidien d’un poilu de la première guerre mondiale sur Facebook : nouvelle forme de médiation, nouvelle expérience ?

in Les mondes de la médiation culturelle (in press)

« En 2013, le Musée de la Grande Guerre du Pays de Meaux et l’agence de communication DDB ont élaboré une page Facebook d’un genre nouveau. Facebook 1914, le quotidien de la première guerre offre une ... [more ▼]

« En 2013, le Musée de la Grande Guerre du Pays de Meaux et l’agence de communication DDB ont élaboré une page Facebook d’un genre nouveau. Facebook 1914, le quotidien de la première guerre offre une forme de médiation a priori inédite pour un musée français. Elle présente l’histoire d’un personnage de fiction, Léon Vivien, qui raconte son quotidien lors de la première guerre mondiale, sur Facebook, comme si ce réseau social avait existé à cette époque. Cette contribution met en évidence certains des effets de sens de la page par une analyse sémiotique du dispositif et une analyse thématique de ses contenus. Nous questionnons ensuite cette « nouvelle » forme de médiation qui se dit « participante » et qui, en réalité, reste assez classique dans son contenu et sous-exploite le potentiel de Facebook. » [less ▲]

Conservazione e ricezione dei documenti pontifici in Italia settentrionale: il caso del monastero cistercense di Chiaravalle Milanese (secoli XII-XVI)

in Salemme, Timothy; Renault, Jean-Baptiste (Eds.) Conservation et réception des documents pontificaux par les Ordres religieux (XIe-XVe siècles). Actes du colloque international. Nancy, 12-13 décembre 2013 (in press)

Discrete-Phase Sequence Design with Stopband and PSL Constraints for Cognitive Radar

in Proceedings of EuRAD 2020 (in press)

We present the design of discrete-phase sequences considering simultaneously the peak sidelobe level (PSL) and avoiding reserved frequency bands which are occupied by narrowband interferers or ... [more ▼]

We present the design of discrete-phase sequences considering simultaneously the peak sidelobe level (PSL) and avoiding reserved frequency bands which are occupied by narrowband interferers or communications. We use the coordinate descent framework and propose an algorithm to design discrete-phase sequences with spectral power suppressed in arbitrary bands and with low auto-correlation sidelobes in terms of PSL. Our proposed algorithm exploits fast Fourier transform and is, therefore, computationally efficient. The over-the-air experiments using implementation on software-defined radio show reasonable agreement with numerical simulations and feasibility for field-deployment [less ▲]

Designing and managing an online, personalised research writing course for postgraduates

in Mcdiarmid, Carole (Ed.) Exploring pedagogical approaches in EAP teaching (in press)

This paper describes and evaluates a multidisciplinary, online research writing course for PhD students. First, we explain our course rationale and set-up. The core principles are personalised, self ... [more ▼]

This paper describes and evaluates a multidisciplinary, online research writing course for PhD students. First, we explain our course rationale and set-up. The core principles are personalised, self-regulated and peer learning, and the optimal use of class time. This is achieved through the following components: an e-coursebook developed in-house; tasks preparing students for the workshops; workshops; writing and reflection; peer review; and individual consultations. Next, we review participants’ feedback from course evaluation surveys. Many students liked the online format although most would prefer the peer review and discussion of theory to happen ‘offline’. A key finding for course efficacy is that students greatly valued working with their own examples in the workshops. They saw this and independent learning tasks as the greatest drivers of their writing development. They also benefited from multidisciplinary peer review. As regards the writing and reflection, all students chose to write on their own and the writing reflection tool was deemed ineffective. We furthermore discuss our (teachers’) perceptions of the affordances and challenges of this course format. On the one hand, it allows workshops to be devoted to collaborative tasks, reflection and data-driven learning. On the other hand, preparing such workshops is very time-consuming, while the multiple components and regular task submissions carry a heavy administrative burden. The paper concludes with how lessons learnt have been implemented into the current course configuration. [less ▲]

The Elements of Visual Art Recommendation: Learning Latent Semantic Representations of Paintings

in Proceedings of the 2023 CHI Conference on Human Factors in Computing Systems (CHI ’23) (2023, April)

Artwork recommendation is challenging because it requires understanding how users interact with highly subjective content, the complexity of the concepts embedded within the artwork, and the emotional and ... [more ▼]

Artwork recommendation is challenging because it requires understanding how users interact with highly subjective content, the complexity of the concepts embedded within the artwork, and the emotional and cognitive reflections they may trigger in users. In this paper, we focus on efficiently capturing the elements (i.e., latent semantic relationships) of visual art for personalized recommendation. We propose and study recommender systems based on textual and visual feature learning techniques, as well as their combinations. We then perform a small-scale and a large-scale user-centric evaluation of the quality of the recommendations. Our results indicate that textual features compare favourably with visual ones, whereas a fusion of both captures the most suitable hidden semantic relationships for artwork recommendation. Ultimately, this paper contributes to our understanding of how to deliver content that suitably matches the user's interests and how they are perceived. [less ▲]

Regional heterogeneity and individual characteristics in the development of a European tax policy: historical insights from Luxembourg

in Danescu, Elena; Dima, Alina Mihaela (Eds.) Fostering recovery through metaverse business modelling - An interdisciplinary analysis of the new paradigm shift (2023, March)

Luxembourg is currently one of the most politically stable, consensus-oriented, and prosperous countries in the world, characterised by am advanced social market economy, and a level of material wellbeing ... [more ▼]

Luxembourg is currently one of the most politically stable, consensus-oriented, and prosperous countries in the world, characterised by am advanced social market economy, and a level of material wellbeing above the EU average. Its strong fiscal position is well illustrated by a longstanding AAA credit rating, a significant accumulation of government financial assets, and a distinct fiscal approach. In this light, this paper aims to investigate the specific features of the tax system in Luxembourg from a multidisciplinary perspective by analysing historical sources and exploring the development of these particularities over time, their impact on the socioeconomic context and their repercussions for the European integration process, especially in the design and completion of Economic and Monetary Union (EMU). [less ▲]

Die Grenzen aufgezeigt:Technische Innovation und räumliche Abstraktion am Beispiel früher Landkarten der Grenzregion zwischen dem Herzogtum Luxemburg und dem Kurfürstentum Trier

in Schröder, Lina; Wegewitz, Markus (Eds.) Europäische Grenzregionen. Neue Wege im Umgang mit historischen Raum- und Grenzkonzeptionen in der Geschichtswissenschaft (2023, March)

Die Ausbildung und Verfestigung der kurtrierischen und luxemburgischen Landesherrschaften war im 14. Jahrhundert weitgehend zum Abschluss gekommen. Die Transformation vom Personenverbands- zum ... [more ▼]

Die Ausbildung und Verfestigung der kurtrierischen und luxemburgischen Landesherrschaften war im 14. Jahrhundert weitgehend zum Abschluss gekommen. Die Transformation vom Personenverbands- zum Flächenstaat frühneuzeitlicher Prägung hatte die Ausbildung einer zunehmend deutlicheren Grenze zwischen beiden Territorien zur Folge. Ebenso formierte sich auch eine Grenze im Grenzraum mit Frankreich und Lothringen. Die vereinfachende Darstellung komplexer teils überlagerter Grenzzonen in Form von abstrahierenden Linien musste von den zeitgenössischen Kartographen jedoch erst noch entwickelt werden. Die älteste regionale Karte mit einer angedeuteten partiellen Grenzmarkierung stammt aus dem Jahr 1555. Eine zunehmende Professionalisierung der Kartographie gelang ab der zweiten Hälfte des 16. Jahrhunderts durch Landesaufnahmen, initiiert von den jeweiligen Landesherren. Die Intention der Auftraggeber war dabei ähnlich: einerseits sollte das jeweilige Territorium durch die Karte möglichst als geschlossen beherrschter Raum dargestellt werden, andererseits galt es, die bisher nur verbal beschriebenen teils strittigen Grenzen als abstrakte Linien deutlich sichtbar zu machen. Die Karten der Landesaufnahmen waren zunächst geheim, dennoch fanden sie bereits nach wenigen Jahren Eingang in die Atlanten von Ortelius, de Jode und Mercator. Diese beeinflussten wiederum die Karten der Region in den späteren Atlanten der niederländischen, französischen und süddeutschen Kartenverleger. Der Beitrag beschreibt, ab wann und in welcher Form Grenzen in frühen Karten (16.-18. Jahrhundert) dargestellt wurden. Besonders in den Blick genommen wird der Prozess der Ausbildung von Linien zur abstrakten Darstellung unklarer, teils strittiger Grenzräume sowie die zunehmende Professionalisierung und Genauigkeit in der kartographischen Darstellung durch Vermessungen im Feld. [less ▲]

Bringing Movement to Digital Tasks at the Office: Designing an Acceptably Active Interface Interaction for Sending Emails

in Proceedings of the Seventeenth International Conference on Tangible, Embedded, and Embodied Interaction TEI'23 (2023, February)

While working on a computer typically involves sitting for prolonged periods of time, sedentary work routines are associated with numerous health issues. To address this societal concern, existing ... [more ▼]

While working on a computer typically involves sitting for prolonged periods of time, sedentary work routines are associated with numerous health issues. To address this societal concern, existing solutions trigger physical activity as a break from work, rather than a part of it. In this research, we explore a vision for physically active ways of working, by transforming mundane digital tasks into physically active ones. As a research artifact and design exemplar, we present A2-I2, an innovative tangible system for sending emails. After loading their email onto a physical “letter” token, office workers must walk to a physical mailbox located in the office space. Understanding what design qualities influence the experience and acceptability of such systems is a necessary step toward the design of acceptably active interface interactions. We report on a preliminary user test with 8 participants. With this project, we aim to inspire future tangible and embodied systems addressing the timely issue of sedentary behavior at work. [less ▲]

Terminal-Aware Multi-Connectivity Scheduler for Uplink Multi-Layer Non-Terrestrial Networks

in IEEE Global Communications Conference (Globecom) (2023, January 12)

This paper introduces the concept of multi-connectivity (MC) to the multi-orbit non-terrestrial networks (NTNs), where user terminals can be served by more than one satellite to achieve higher peak ... [more ▼]

This paper introduces the concept of multi-connectivity (MC) to the multi-orbit non-terrestrial networks (NTNs), where user terminals can be served by more than one satellite to achieve higher peak throughput. MC is a technique initially introduced by the 3rd Generation Partnership Project (3GPP) for terrestrial communications in 4G and 5G, it has shown much gain in the terrestrial domain and this paper explores areas where this concept can benefit the satellite domain. MC can increase throughput, but this entails increased power consumption at user terminal for uplink transmissions. The energy efficiency of uplink communications can be improved by designing efficient scheduling schemes, and to this end, we developed a terminal aware multi-connectivity scheduling algorithm. This proposed algorithm uses the available radio resources and propagation information to intelligently define a dynamic resource allocation pattern, that optimally routes traffic so as to maximize uplink data rate while minimizing the energy consumption at the UT. The algorithm operates with the terminal differentiating multi-layer NTN resource scheduling architecture, which has a softwarized dispatcher at the network layer that classifies and differentiates the packets based on terminal type. The performance of the proposed algorithm was compared with round robin and joint carrier schedulers in terms of uplink data rate and energy efficiency. We also provide architectural design of implementable schedulers for multi-orbital satellite networks that can operate with different classes of terminals. [less ▲]

Federated Learning as a Solution for Problems Related to Intergovernmental Data Sharing

in Proceedings of the 56th Hawaii International Conference on System Sciences (2023, January 03)

To address global problems, intergovernmental collaboration is needed. Modern solutions to these problems often include data-driven methods like artificial intelligence (AI), which require large amounts ... [more ▼]

To address global problems, intergovernmental collaboration is needed. Modern solutions to these problems often include data-driven methods like artificial intelligence (AI), which require large amounts of data to perform well. However, data sharing between governments is limited. A possible solution is federated learning (FL), a decentralised AI method created to utilise personal information on edge devices. Instead of sharing data, governments can build their own models and just share the model parameters with a centralised server aggregating all parameters, resulting in a superior overall model. By conducting a structured literature review, we show how major intergovernmental data sharing challenges like disincentives, legal and ethical issues as well as technical constraints can be solved through FL. Enhanced AI while maintaining privacy through FL thus allows governments to collaboratively address global problems, which will positively impact governments and citizens. [less ▲]

Astute Approach to Handling Memory Layouts of Regular Data Structures

in Algorithms and Architectures for Parallel Processing (2023, January)

Programmers of high-performance applications face many challenging aspects of contemporary hardware architectures. One of the critical aspects is the efficiency of memory operations which is affected not ... [more ▼]

Programmers of high-performance applications face many challenging aspects of contemporary hardware architectures. One of the critical aspects is the efficiency of memory operations which is affected not only by the hardware parameters such as memory throughput or cache latency but also by the data-access patterns, which may influence the utilization of the hardware, such as re-usability of the cached data or coalesced data transactions. Therefore, a performance of an algorithm can be highly impacted by the layout of its data structures or the order of data processing which may translate into a more or less optimal sequence of memory operations. These effects are even more pronounced on highly-parallel platforms, such as GPUs, which often employ specific execution models (lock-step) or memory models (shared memory). In this work, we propose a modern, astute approach for managing and implementing memory layouts with first-class structures that is very efficient and straightforward. This approach was implemented in Noarr, a GPU-ready portable C++ library that utilizes generic programming, functional design, and compile-time computations to allow the programmer to specify and compose data structure layouts declaratively while minimizing the indexing and coding overhead. We describe the main principles on code examples and present a performance evaluation that verifies our claims regarding its efficiency. [less ▲]

La responsabilité civile du fait des lycanthropes

in Calcio, Mathilde (Ed.) Horreur et Droit (2023)

SoK: Secure E-Voting with Everlasting Privacy

in Proceedings on Privacy Enhancing Technologies (PoPETs) (2023)

Vote privacy is a fundamental right, which needs to be protected not only during an election, or for a limited time afterwards, but for the foreseeable future. Numerous electronic voting (e-voting ... [more ▼]

Vote privacy is a fundamental right, which needs to be protected not only during an election, or for a limited time afterwards, but for the foreseeable future. Numerous electronic voting (e-voting) protocols have been proposed to address this challenge, striving for everlasting privacy. This property guarantees that even computationally unbounded adversaries cannot break privacy of past elections. The broad interest in secure e-voting with everlasting privacy has spawned a large variety of protocols over the last three decades. These protocols differ in many aspects, in particular the precise security properties they aim for, the threat scenarios they consider, and the privacy-preserving techniques they employ. Unfortunately, these differences are often opaque, making analysis and comparison cumbersome. In order to overcome this non-transparent state of affairs, we systematically analyze all e-voting protocols designed to provide everlasting privacy. First, we illustrate the relations and dependencies between all these different protocols. Next, we analyze in depth which protocols do provide secure and efficient approaches to e-voting with everlasting privacy under realistic assumptions, and which ones do not. Eventually, based on our extensive and detailed treatment, we identify which research problems in this field have already been solved, and which ones are still open. Altogether, our work offers a well-founded reference point for conducting research on secure e-voting with everlasting privacy as well as for future-proofing privacy in real-world electronic elections. [less ▲]

Efficient Hessian-based DNN Optimization via Chain-Rule Approximation

in Proceedings of the 6th Joint International Conference on Data Science Management of Data (10th ACM IKDD CODS and 28th COMAD) (2023)

Efficient Hamiltonian Reduction for Quantum Annealing on SatCom Beam Placement Problem

in IEEE International Conference on Communications (ICC), Rome, Italy, May 2023 (2023)

GEO Payload Power Minimization: Joint Precoding and Beam Hopping Design

in Proceedings of IEEE Global Communications Conference GLOBECOM 2022 (2022, December 05)

This paper aims to determine linear precoding (LP) vectors, beam hopping (BH), and discrete DVB-S2X transmission rates jointly for the GEO satellite communication systems to minimize the payload power ... [more ▼]

This paper aims to determine linear precoding (LP) vectors, beam hopping (BH), and discrete DVB-S2X transmission rates jointly for the GEO satellite communication systems to minimize the payload power consumption and satisfy ground users’ demands within a time window. Regarding constraint on the maximum number of illuminated beams per time slot, the technical requirement is formulated as a sparse optimization problem in which the hardware-related beam illumination energy is modeled in a sparsity form of the LP vectors. To cope with this problem, the compressed sensing method is employed to transform the sparsity parts into the quadratic form of precoders. Then, an iterative window-based algorithm is developed to update the LP vectors sequentially to an efficient solution. Additionally, two other two-phase frameworks are also proposed for comparison purposes. In the first phase, these methods aim to determine the MODCOD transmission schemes for users to meet their demands by using a heuristic approach or DNN tool. In the second phase, the LP vectors of each time slot will be optimized separately based on the determined MODCOD schemes. [less ▲]

Joint Linear Precoding and DFT Beamforming Design for Massive MIMO Satellite Communication

in IEEE Global Communications Conference GLOBECOM 2022 (2022, December)

DRIVE-B5G: A Flexible and Scalable Platform Testbed for B5G-V2X Networks

in DRIVE-B5G: A Flexible and Scalable Platform Testbed for B5G-V2X Networks (2022, December)

Unlike previous mobile networks, 5G and beyond (B5G) networks are expected to be the key enabler of various vertical industries such as eHealth, intelligent transportation, and Industrial IoT verticals ... [more ▼]

Unlike previous mobile networks, 5G and beyond (B5G) networks are expected to be the key enabler of various vertical industries such as eHealth, intelligent transportation, and Industrial IoT verticals. To support that, B5G networks enable to sharing of common physical resources (radio, computation, network) among different tenants, thanks to network slicing concept and network softwarization technologies, including Software Defined Networking (SDN) and Network Function Virtualization (NFV). Therefore, new research challenges related to B5G networks have emerged, such as resources management and orchestration, service chaining, security, and QoS management. However, there is a lack of a realistic platform enabling researchers to design and validate their solutions effectively, since B5G networks are still in their early stages. In this paper, we first discuss the different methods for deploying realistic B5G platforms for the V2X vertical, including the key B5G technologies. Then, we describe DRIVE-B5G, a novel platform that serves as an end-to-end test-bed to emulate a vehicular network environment, allowing researchers to provide proof of concept, validate, and evaluate their research approaches. [less ▲]

Lightweight Permutation-Based Cryptography for the Ultra-Low-Power Internet of Things

in Bella, Giampaolo; Doinea, Mihai; Janicke, Helge (Eds.) Innovative Security Solutions for Information Technology and Communications 15th International Conference, SECITC 2022, Virtual Event, December 8-9, 2022, Revised Selected Papers (2022, December)

The U.S. National Institute of Standards and Technology is currently undertaking a process to evaluate and eventually standardize one or more "lightweight" algorithms for authenticated encryption and ... [more ▼]

The U.S. National Institute of Standards and Technology is currently undertaking a process to evaluate and eventually standardize one or more "lightweight" algorithms for authenticated encryption and hashing that are suitable for resource-restricted devices. In addition to security, this process takes into account the efficiency of the candidate algorithms in various hardware environments (e.g. FPGAs, ASICs) and software platforms (e.g. 8, 16, 32-bit microcontrollers). However, while there exist numerous detailed benchmarking results for 8-bit AVR and 32-bit ARM/RISC-V/ESP32 microcontrollers, relatively little is known about the candidates' efficiency on 16-bit platforms. In order to fill this gap, we present a performance evaluation of the final-round candidates Ascon, Schwaemm, TinyJambu, and Xoodyak on the MSP430 series of ultra-low-power 16-bit microcontrollers from Texas Instruments. All four algorithms were explicitly designed to achieve high performance in software and have further in common that the underlying primitive is a permutation. We discuss how these permutations can be implemented efficiently in Assembly language and analyze how basic design decisions impact their execution time on the MSP430 architecture. Our results show that, overall, Schwaemm is the fastest algorithm across various lengths of data and associated data, respectively. Xoodyak has benefits when a large amount of associated data is to be authenticated, whereas TinyJambu is very efficient for the authentication of short messages. [less ▲]

Edge Computing-enabled Intrusion Detection for C-V2X Networks using Federated Learning

in The 2022 IEEE Global Communications Conference (GLOBECOM) (2022, December)

Intrusion detection systems (IDS) have already demonstrated their effectiveness in detecting various attacks in cellular vehicle-to-everything (C-V2X) networks, especially when using machine learning (ML ... [more ▼]

Intrusion detection systems (IDS) have already demonstrated their effectiveness in detecting various attacks in cellular vehicle-to-everything (C-V2X) networks, especially when using machine learning (ML) techniques. However, it has been shown that generating ML-based models in a centralized way consumes a massive quantity of network resources, such as CPU/memory and bandwidth, which may represent a critical issue in such networks. To avoid this problem, the new concept of Federated Learning (FL) emerged to build ML-based models in a distributed and collaborative way. In such an approach, the set of nodes, e.g., vehicles or gNodeB, collaborate to create a global ML model trained across these multiple decentralized nodes, each one with its respective data samples that are not shared with any other nodes. In this way, FL enables, on the one hand, data privacy since sharing data with a central location is not always feasible and, on the other hand, network overhead reduction. This paper designs a new IDS for C-V2X networks based on FL. It leverages edge computing to not only build a prediction model in a distributed way but also to enable low-latency intrusion detection. Moreover, we build our FL-based IDS on top of the well-known CIC-IDS2018 dataset, which includes the main network attacks. Noting that, we first perform feature engineering on the dataset using the ANOVA method to consider only the most informative features. Simulation results show the efficiency of our system compared to the existing solutions in terms of attack detection accuracy while reducing network resource consumption. [less ▲]

Power Allocation for Space-Terrestrial Cooperation Systems with Statistical CSI

in IEEE Global Communications Conference (IEEE Globecom), Rio de Janeiro, Brazil, Dec. 2022 (2022, December)

Edge Computing enabled Intrusion Detection for C-V2X Networks using Federated Learning

in The 2022 IEEE Global Communications Conference (GLOBECOM) (2022, December)

Intrusion detection systems (IDS) have already demonstrated their effectiveness in detecting various attacks in cellular vehicle-to-everything (C-V2X) networks, especially when using machine learning (ML ... [more ▼]

Intrusion detection systems (IDS) have already demonstrated their effectiveness in detecting various attacks in cellular vehicle-to-everything (C-V2X) networks, especially when using machine learning (ML) techniques. However, it has been shown that generating ML-based models in a centralized way consumes a massive quantity of network resources, such as CPU/memory and bandwidth, which may represent a critical issue in such networks. To avoid this problem, the new concept of Federated Learning (FL) emerged to build ML-based models in a distributed and collaborative way. In such an approach, the set of nodes, e.g., vehicles or gNodeB, collaborate to create a global ML model trained across these multiple decentralized nodes, each one with its respective data samples that are not shared with any other nodes. In this way, FL enables, on the one hand, data privacy since sharing data with a central location is not always feasible and, on the other hand, network overhead reduction. This paper designs a new IDS for C-V2X networks based on FL. It leverages edge computing to not only build a prediction model in a distributed way but also to enable low-latency intrusion detection. Moreover, we build our FL-based IDS on top of the well-known CIC-IDS2018 dataset, which includes the main network attacks. Noting that, we first perform feature engineering on the dataset using the ANOVA method to consider only the most informative features. Simulation results show the efficiency of our system compared to the existing solutions in terms of attack detection accuracy while reducing network resource consumption. [less ▲]

Security Modeling and Analysis of Moving Target Defense in Software Defined Networks

in Security Modeling and Analysis of Moving Target Defense in Software Defined Networks (2022, November 28)

The use of traditional defense mechanisms or intrusion detection systems presents a disadvantage for defenders against attackers since these mechanisms are essentially reactive. Moving target defense (MTD ... [more ▼]

The use of traditional defense mechanisms or intrusion detection systems presents a disadvantage for defenders against attackers since these mechanisms are essentially reactive. Moving target defense (MTD) has emerged as a proactive defense mechanism to reduce this disadvantage by randomly and continuously changing the attack surface of a system to confuse attackers. Although significant progress has been made recently in analyzing the security effectiveness of MTD mechanisms, critical gaps still exist, especially in maximizing security levels and estimating network reconfiguration speed for given attack power. In this paper, we propose a set of Petri Net models and use them to perform a comprehensive evaluation regarding key security metrics of Software-Defined Network (SDNs) based systems adopting a time-based MTD mechanism. We evaluate two use-case scenarios considering two different types of attacks to demonstrate the feasibility and applicability of our models. Our analyses showed that a time-based MTD mechanism could reduce the attackers’ speed by at least 78% compared to a system without MTD. Also, in the best-case scenario, it can reduce the attack success probability by about ten times. [less ▲]

Specifying Source Code and Signal-based Behaviour of CPS Components

in Dawes, Joshua; Bianculli, Domenico (Eds.) Proceedings of the 18th International Conference on Formal Aspects of Component Software (2022, November)

Specifying properties over the behaviour of components of Cyber-Physical Systems usually focuses on the behaviour of signals, i.e., the behaviour of the physical part of the system, leaving the behaviour ... [more ▼]

Specifying properties over the behaviour of components of Cyber-Physical Systems usually focuses on the behaviour of signals, i.e., the behaviour of the physical part of the system, leaving the behaviour of the cyber components implicit. There have been some attempts to provide specification languages that enable more explicit reference to the behaviour of cyber components, but it remains awkward to directly express the behaviour of both cyber and physical components in the same specification, using one formalism. In this paper, we introduce a new specification language, Source Code and Signal Logic (SCSL), that 1) provides syntax specific to both signals and events originating in source code; and 2) does not require source code events to be abstracted into signals. We introduce SCSL by giving its syntax and semantics, along with examples. We then provide a comparison between SCSL and existing specification languages, using an example property, to show the benefit of using SCSL to capture certain types of properties. [less ▲]

DISCOV: Stimulating Physical Activity through an Explorative Interactive Walking Experience

in [ ] With Design: Reinventing Design Modes (2022, November)

Aware of the consequences of their inactive lifestyles, many people still struggle to integrate enough physical activity into their busy lives. Interventions that nudge to reinforce existing active ... [more ▼]

Aware of the consequences of their inactive lifestyles, many people still struggle to integrate enough physical activity into their busy lives. Interventions that nudge to reinforce existing active behavior seem therefore more likely to be effective than those adding an activity to daily routines. To encourage people to increase their physical activity level, we designed Discov, a network of physical waypoints triggering people to lengthen their walks. Placed in a public park, Discov encourages people to explore their surroundings in a fun and challenging way by creating an interactive walking experience. Adopting a Research-through-Design approach, we explore the potential of the design of accessible infrastructures and human-environment interactions to impact public health by nudging citizens into being more physically active. We discuss insights gathered through this process and report on first user tests of this interactive walking experience. [less ▲]

Asynja: Sensorial Design for Running Motivation

in [ ] With Design: Reinventing Design Modes (2022, November)

If starting to run is an easy decision, committing to a long-term running routine proves to be a more challenging endeavor for many people. In this pictorial, we unravel the design process of Asynja, an ... [more ▼]

If starting to run is an easy decision, committing to a long-term running routine proves to be a more challenging endeavor for many people. In this pictorial, we unravel the design process of Asynja, an artefact that triggers exercise imagery by using natural scents related to running. Relying on peripheral interaction, this research probe subtly nudges users to go running, thereby supporting them to transform their positive intentions into actions. Exploring sensoriality as a design opportunity for behavior change interventions, we invite the community to expand the design space of exercise-related motivational products and systems. [less ▲]

Hybrid Beamforming Design for OFDM Dual-Function Radar-Communication System with Double-Phase-Shifter Structure

in 2022 30th European Signal Processing Conference (EUSIPCO) (2022, October 18)

In this paper, the problem of the hybrid beamforming (HBF) for a millimeter wave (mmWave) orthogonal frequency division multiplexing (OFDM) dual-function radar-communication (DFRC) system in the presence ... [more ▼]

In this paper, the problem of the hybrid beamforming (HBF) for a millimeter wave (mmWave) orthogonal frequency division multiplexing (OFDM) dual-function radar-communication (DFRC) system in the presence of signal-dependent interference is studied. The HBF network is based on the subarray connection architecture combining with the double-phase-shifter (DPS) structure. To achieve the dual functionality, we formulate the problem by maximizing the communication spectral efficiency subject to the constraints of radar integrated side-lobe to main-lobe ratio (ISMR), space-frequency nulling (SFN) and energy. An efficient algorithm based on the consensus alternating direction method of multipliers (CADMM) frame-work is developed to tackle the resultant nonconvex problem. Simulation results demonstrate the superiority of the proposed DPS structure and HBF algorithm. [less ▲]

Automatic Repair and Deadlock Detection for Parameterized Systems

in Automatic Repair and Deadlock Detection for Parameterized Systems (2022, October 15)

Performance Modeling of Weather Forecast Machine Learning for Efficient HPC

in International Conference on Distributed Computing Systems (ICDCS), Italy 10-13 July 2022 (2022, October 13)

High-performance computing is a prime area for many applications. Majorly, weather and climate forecast applications use the HPC system because it needs to give a good result with low latency. In recent ... [more ▼]

High-performance computing is a prime area for many applications. Majorly, weather and climate forecast applications use the HPC system because it needs to give a good result with low latency. In recent years machine learning and deep learning models have been widely used to forecast the weather. However, to the best of the author’s knowledge, many applications do not effectively utilise the HPC system for training, testing, validation, and inference of weather data. Our experiment is to conduct performance modeling and benchmark analysis of weather and climate forecast machine learning models and determine the characteristics between the application, model and the underlying HPC system. Our results will help the researchers improvise and optimise the weather forecast system and use the HPC system efficiently. [less ▲]

5G-NTN GEO-based Over-The-Air Demonstrator using OpenAirInterface

in 5G-NTN GEO-based Over-The-Air Demonstrator using OpenAirInterface (2022, October)

5G services combined with the satellites, also termed 5G NonTerrestrial Networks (5G-NTN), have the capability of providing connectivity to the areas which were previously either unreachable or too costly ... [more ▼]

5G services combined with the satellites, also termed 5G NonTerrestrial Networks (5G-NTN), have the capability of providing connectivity to the areas which were previously either unreachable or too costly to be reached by terrestrial communication networks. Proof-of-Concept (POC) demonstrators, preferably based on open-source implementation are desirable to expedite the ongoing research on 5G-NTN. In this work, we discuss the contributions made during the project 5G-GOA: 5G-Enabled Ground Segment Technologies Over-The-Air Demonstrator which aims to provide direct access to 5G services to a UE through a transparent payload Geostationary (GEO) satellite. 5G-GOA uses the open-source Software-Defined-Radio (SDR) platform OpenAirInterface (OAI) and does the necessary adaptations to achieve its objectives. Adaptations span physical layer techniques (e.g. synchronization) up to upper layer implementations (e.g., timers and random-access procedures) of the Radio Access Network (RAN). The adaptations are based on 3GPP 5G-NTN discussions and the solutions are compliant with the recently frozen 3GPP Release-17. An endto-end SDR-based 5G-NTN demonstrator has been developed for Over-The-Satellite (OTS) testing. We present results from several experiments that were conducted for in-lab validation of the demonstrator using a satellite channel emulator before going live with OTS tests. Experimental results indicate the readiness of the demonstrator for OTS testing which is scheduled during ICSSC 2022. The source code has been submitted to OAI public repository and is available for testing. [less ▲]

The EU's Digital Identity Policy: Tracing Policy Punctuations

in Proceedings of the 15th International Conference on Theory and Practice of Electronic Governance (ICEGOV) (2022, October)

This paper analyzes the development of the European Union’s digital identity policy. The analysis focuses on the dynamics leading to a sudden shift from identity management as a sensitive topic under ... [more ▼]

This paper analyzes the development of the European Union’s digital identity policy. The analysis focuses on the dynamics leading to a sudden shift from identity management as a sensitive topic under national competence towards a common, harmonized, user-centric European Digital Identity Framework layering on top of Member States’ existing systems. We adopted a syncretic approach to Punctuated Equilibrium Theory and focused specifically on the concept of policy punctuations and policy image. Process tracing is used as a method to trace and interpret causal mechanisms of policy processes. The empirical analysis is grounded in elite interviews and policy documentation. To open up the black box of policy-making, we analyze and disaggregate the policy process. We thereby provide a better understanding of the historical-political and technological mechanisms that determine particular policy outcomes. [less ▲]

Transition Pathways towards Design Principles of Self-Sovereign Identity

in Proceedings of the 43rd International Conference on Information Systems (ICIS) (2022, October)

Society’s accelerating digital transformation during the COVID-19 pandemic highlighted clearly that the Internet lacks a secure, efficient, and privacy-oriented model for identity. Self-sovereign identity ... [more ▼]

Society’s accelerating digital transformation during the COVID-19 pandemic highlighted clearly that the Internet lacks a secure, efficient, and privacy-oriented model for identity. Self-sovereign identity (SSI) aims to address core weaknesses of siloed and federated approaches to digital identity management from both users’ and service providers’ perspectives. SSI emerged as a niche concept in libertarian communities, and was initially strongly associated with blockchain technology. Later, when businesses and governments began to invest, it quickly evolved towards a mainstream concept. To investigate this evolution and its effects on SSI, we conduct design science research rooted in the theory of technological transition pathways. Our study identifies nine core design principles of SSI as deployed in relevant applications, and discusses associated competing political and socio-technical forces in this space. Our results shed light on SSI’s key characteristics, its development pathway, and tensions in the transition between regimes of digital identity management. [less ▲]

PEELER: Learning to Effectively Predict Flakiness without Running Tests

in Proceedings of the 38th IEEE International Conference on Software Maintenance and Evolution (2022, October)

—Regression testing is a widely adopted approach to expose change-induced bugs as well as to verify the correctness/robustness of code in modern software development settings. Unfortunately, the ... [more ▼]

—Regression testing is a widely adopted approach to expose change-induced bugs as well as to verify the correctness/robustness of code in modern software development settings. Unfortunately, the occurrence of flaky tests leads to a significant increase in the cost of regression testing and eventually reduces the productivity of developers (i.e., their ability to find and fix real problems). State-of-the-art approaches leverage dynamic test information obtained through expensive re-execution of test cases to effectively identify flaky tests. Towards accounting for scalability constraints, some recent approaches have built on static test case features, but fall short on effectiveness. In this paper, we introduce PEELER, a new fully static approach for predicting flaky tests through exploring a representation of test cases based on the data dependency relations. The predictor is then trained as a neural network based model, which achieves at the same time scalability (because it does not require any test execution), effectiveness (because it exploits relevant test dependency features), and practicality (because it can be applied in the wild to find new flaky tests). Experimental validation on 17,532 test cases from 21 Java projects shows that PEELER outperforms the state-of-the-art FlakeFlagger by around 20 percentage points: we catch 22% more flaky tests while yielding 51% less false positives. Finally, in a live study with projects in-the-wild, we reported to developers 21 flakiness cases, among which 12 have already been confirmed by developers as being indeed flaky. [less ▲]

The Role of Cultural Fit in the Adoption of Fashionable IT: A Blockchain Case Study

in Forty-Third International Conference on Information Systems (2022, October)

Investments in fashionable IT do not make organizations more successful than investments in less fashionable alternatives. Many organizations nevertheless associate with fashionable IT to signal ... [more ▼]

Investments in fashionable IT do not make organizations more successful than investments in less fashionable alternatives. Many organizations nevertheless associate with fashionable IT to signal compliance with norms of progress and rationality. These decisions can be risky as fashionable IT is often surrounded by wishful and unbalanced discourse, especially in the ‘fashion up-swing’. Engagement with fashionable IT thus requires the ability to navigate hype narratives and fit the new technology into the adopting organization. Fit needs to be established in many regards, such as political and technological. In this paper, we explore a third and so far, understudied perspective: cultural fit between the values attributed to the fashionable IT through the fashion discourse and those of the recipient organizational context. Through an inductive case study of two blockchain projects, we find that cultural fit can equally be an important determinant for successful adoption of fashionable IT. Moreover, we develop a process theory for how cultural fit can be established through a process of cultural sensemaking and dissonance reduction along two recursive pathways. Adopting organizations can change their implementation of fashionable IT systems and re-frame the narratives surrounding them to fit their organization’s cultural values. Alternatively, they can transform their local or overarching organizational culture by integrating values attributed to the fashionable IT. Overall, we contribute a much-needed organizational culture perspective to IT fashions and extend the discussions on IT cultural conflict. [less ▲]

Android Malware Detection Using BERT

in Jianying, Zhou (Ed.) Applied Cryptography and Network Security Workshops (2022, September 24)

In this paper, we propose two empirical studies to (1) detect Android malware and (2) classify Android malware into families. We rst (1) reproduce the results of MalBERT using BERT models learning with ... [more ▼]

In this paper, we propose two empirical studies to (1) detect Android malware and (2) classify Android malware into families. We rst (1) reproduce the results of MalBERT using BERT models learning with Android application's manifests obtained from 265k applications (vs. 22k for MalBERT) from the AndroZoo dataset in order to detect malware. The results of the MalBERT paper are excellent and hard to believe as a manifest only roughly represents an application, we therefore try to answer the following questions in this paper. Are the experiments from MalBERT reproducible? How important are Permissions for mal- ware detection? Is it possible to keep or improve the results by reducing the size of the manifests? We then (2) investigate if BERT can be used to classify Android malware into families. The results show that BERT can successfully di erentiate malware/goodware with 97% accuracy. Further- more BERT can classify malware families with 93% accuracy. We also demonstrate that Android permissions are not what allows BERT to successfully classify and even that it does not actually need it. [less ▲]

Institutional determinants of intersectional inequalities in science

in BRIDGES BETWEEN DISCIPLINES: GENDER IN STEM AND SOCIAL SCIENCES (2022, September 12)

The impact of total cost of ownership on MaaS system appeal using an agent-based approach

in The impact of total cost of ownership on MaaS system appeal using an agent-based approach (2022, September)

Despite the interest in the MaaS system is growing fast within the scientific community, it remains uncertain if MaaS could be a potential tool able to reduce car ownership. This study aims to capture the ... [more ▼]

Despite the interest in the MaaS system is growing fast within the scientific community, it remains uncertain if MaaS could be a potential tool able to reduce car ownership. This study aims to capture the impact of the total cost of ownership (TCO) on MaaS demand by endogenizing the MaaS choice and the TCO within the users’ travel choice in an agent-based model. We simulate different TCO price range starting from a benchmark cost in the literature and embed a specific type of MaaS plan which gives unlimited access to the services. Results show a significant growth of MaaS demand when TCO rises, in particular MaaS members are car users who shift their mode choice to public transport by travelling within more trips but in a shorter time slot. In contrast, MaaS users employ public transport for short trips while they still employ cars reducing their travel time but employing the same number of trips when TCO decreases. Results suggest that MaaS might become a more sustainable service by developing specific subsidies to discourage car ownership and by increasing mobility accessibility. [less ▲]

Indicators for assessing the necessity of power system flexibility: a systematic review and literature meta-analysis

in Proceedings of the 18th International Conference on the European Energy Market (EEM) (2022, September)

There are different flexibility options to align power systems to volatile feed-in of renewable electricity sources. The flexibility options differ in the dimensions of time, spatiality, and resource type ... [more ▼]

There are different flexibility options to align power systems to volatile feed-in of renewable electricity sources. The flexibility options differ in the dimensions of time, spatiality, and resource type. To make policy decisions on future energy systems, it is necessary to get a top-down indication of how much power system flexibility is needed. With the ongoing energy transition, there is yet no comprehensive overview of indicators that describe which dimension of flexibility will be necessary to what extent for different energy systems. Therefore, this paper provides a first overview of indicators that can be used to assess the necessity of power system flexibility. Thus, we do a systematic literature review to identify indicators that allow us to estimate the necessity of power system flexibility. We conduct a meta-analysis of these indicators and categorize them as indicators that either stand for an increasing or decreasing necessity of power system flexibility. Our paper can help inform policy, assess needed changes to system operations, increase stakeholder acceptance and investor confidence in implementing new technology and measures. [less ▲]

Learning to Optimize: Balancing Two Conflict Metrics in MB-HTS Networks

in Advanced Satellite Multimedia Conference / Signal Processing for Space Communications Workshop (ASMS), Gratz, Viena, Sept. 2022 (2022, September)

Obfuscating LLVM Intermediate Representation Source Code with NSGA-II

in 15th Intl. Conf. on Computational Intelligence in Security for Information Systems (CISIS'22) (2022, September)

With the generalisation of distributed computing paradigms to sustain the surging demands for massive processing and data-analytic capabilities, the protection of the intellectual property tied to the ... [more ▼]

With the generalisation of distributed computing paradigms to sustain the surging demands for massive processing and data-analytic capabilities, the protection of the intellectual property tied to the executed programs transferred onto these remote shared platforms becomes critical. A more and more popular solution to this problem consists in applying obfuscating techniques, in particular at the source code level. Informally, the goal of obfuscation is to conceal the purpose of a program or its logic without altering its functionality, thus preventing reverse-engineering on the program even with the help of computing resources. This allows to protect software against plagiarism, tampering, or finding vulnerabilities that could be used for different kinds of attacks. The many advantages of code obfuscation, together with its low cost, makes it a popular technique. This paper proposes a novel methodology for source code obfuscation relying on the reference LLVM compiler infrastructure that can be used together with other traditional obfuscation techniques, making the code more robust against reverse engineering attacks. The problem is defined as a Multi-Objective Combinatorial Optimization (MOCO) problem, where the goal is to find sequences of LLVM optimizations that lead to highly obfuscated versions of the original code. These transformations are applied to the back-end pseudo- assembly code (i.e., LLVM Intermediate Representation), thus avoiding any further optimizations by the compiler. Three different problem flavours are defined and solved with popular NSGA-II genetic algorithm. The promising results show the potential of the proposed technique. [less ▲]

Radio Regulation Compliance of NGSO Constellations’ Interference towards GSO Ground Stations

in IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 12–15 September 2022, Virtual Conference (2022, September)

The commercial low earth orbiting (LEO) satellite constellations have shown unprecedented growth. Accordingly, the risk of generating harmful interference to the geostationary orbit (GSO) satellite ... [more ▼]

The commercial low earth orbiting (LEO) satellite constellations have shown unprecedented growth. Accordingly, the risk of generating harmful interference to the geostationary orbit (GSO) satellite services increases with the number of satel- lites in such mega-constellations. As the GSO arc encompasses the primary and existing satellite assets providing essential fixed and broadcasting satellite services, the interference avoidance for this area is of the utmost importance. In particular, non- geostationary orbit (NGSO) operators should comply with the regulations set up both by their national regulators and by the International Telecommunications Union (ITU) to minimize the impact of emissions on existing GSO and non-GSO systems. In this paper, we first provide an overview of the most recent radio regulations that dictate the NGSO-GSO spectral co-existence. Next, we analyze the NGSO-GSO radio frequency interference for the downlink scenario, following the so-called time-simulation methodology introduced by ITU. The probability distribution of aggregated power flux-density for NGSO co-channel interference is evaluated and assessed, adopting different degrees of exclusion angle strategy for interference avoidance. We conclude the paper by discussing the resulting implications for the continuity of operation and service provision and we provide remarks for future work [less ▲]

The Prosody of Cheering in Sport Events

in Proc. Interspeech 2022 (2022, September)

Motivational speaking usually conveys a highly emotional message and its purpose is to invite action. The goal of this paper is to investigate the prosodic realization of one particular type of cheering ... [more ▼]

Motivational speaking usually conveys a highly emotional message and its purpose is to invite action. The goal of this paper is to investigate the prosodic realization of one particular type of cheering, namely inciting cheering for single addressees in sport events (here, long-distance running), using the name of that person. 31 native speakers of German took part in the experiment. They were asked to cheer up an individual marathon runner in a sporting event represented by video by producing his or her name (1-5 syllables long). For reasons of comparison, the participants also produced the same names in isolation and carrier sentences. Our results reveal that speakers use different strategies to meet their motivational communicative goals: while some speakers produced the runners’ names by dividing them into syllables, others pronounced the names as quickly as possible putting more emphasis on the first syllable. A few speakers followed a mixed strategy. Contrary to our expectations, it was not the intensity that mostly contributes to the differences between the different speaking styles (cheering vs. neutral), at least in the methods we were using. Rather, participants employed higher fundamental frequency and longer duration when cheering for marathon runners. [less ▲]