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See detailEvaluation of TPMS Signal Propagation in a Heavy Commercial Vehicle Environement
Rida, Ahmad UL; Soua, Ridha UL; Engel, Thomas UL

in 2021 IEEE 94th Vehicular Technology Conference (VTC2021-Fall) proceedings (2021, September 27)

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See detailL’épreuve de la démocratie ou la démocratie à l’épreuve ?
Danescu, Elena UL

Article for general public (2021)

Considérée parmi les valeurs et principes universels et indivisibles, la démocratie fournit le cadre juste pour l’exercice et la protection des droits humain. C’est ainsi que les Nations Unies adoptent le ... [more ▼]

Considérée parmi les valeurs et principes universels et indivisibles, la démocratie fournit le cadre juste pour l’exercice et la protection des droits humain. C’est ainsi que les Nations Unies adoptent le 15 septembre 1997 la Déclaration universelle sur la démocratie, dont le 10e anniversaire donne lieu la Journée internationale de la démocratie, marquée chaque année depuis 2007, pour sensibiliser à ce sujet les gouvernements et citoyens du monde entier. Depuis 2020, la crise du Covid-19 avec ses défis sociaux, politiques et juridiques majeurs à l'échelle mondiale, ne cesse de mettre la démocratie à l’épreuve en attaquant certains de ses principes constitutifs, notamment la liberté, l’équité, la justice, l’état de droit. Une prise de conscience s’impose. [less ▲]

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See detailDistinct gene-set burden patterns underlie common generalized and focal epilepsies
Koko, Mahmoud; Krause, Roland UL; Sander, Thomas et al

in EBioMedicine (2021), 72

Background Analyses of few gene-sets in epilepsy showed a potential to unravel key disease associations. We set out to investigate the burden of ultra-rare variants (URVs) in a comprehensive range of ... [more ▼]

Background Analyses of few gene-sets in epilepsy showed a potential to unravel key disease associations. We set out to investigate the burden of ultra-rare variants (URVs) in a comprehensive range of biologically informed gene-sets presumed to be implicated in epileptogenesis. Methods The burden of 12 URV types in 92 gene-sets was compared between cases and controls using whole exome sequencing data from individuals of European descent with developmental and epileptic encephalopathies (DEE, n = 1,003), genetic generalized epilepsy (GGE, n = 3,064), or non-acquired focal epilepsy (NAFE, n = 3,522), collected by the Epi25 Collaborative, compared to 3,962 ancestry-matched controls. Findings Missense URVs in highly constrained regions were enriched in neuron-specific and developmental genes, whereas genes not expressed in brain were not affected. GGE featured a higher burden in gene-sets derived from inhibitory vs. excitatory neurons or associated receptors, whereas the opposite was found for NAFE, and DEE featured a burden in both. Top-ranked susceptibility genes from recent genome-wide association studies (GWAS) and gene-sets derived from generalized vs. focal epilepsies revealed specific enrichment patterns of URVs in GGE vs. NAFE. Interpretation Missense URVs affecting highly constrained sites differentially impact genes expressed in inhibitory vs. excitatory pathways in generalized vs. focal epilepsies. The excess of URVs in top-ranked GWAS risk-genes suggests a convergence of rare deleterious and common risk-variants in the pathogenesis of generalized and focal epilepsies. [less ▲]

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See detailHousing Exclusion and Social Work Strategies in Luxembourg
Dujardin, Céline UL

Scientific Conference (2021, September 24)

In the Grand-Duchy of Luxembourg, the demand for affordable housing is significantly higher than the existing offer (Reuter, 2017). For financially disadvantaged households, the housing costs around 40 ... [more ▼]

In the Grand-Duchy of Luxembourg, the demand for affordable housing is significantly higher than the existing offer (Reuter, 2017). For financially disadvantaged households, the housing costs around 40% of the available budget represent a very high expenditure. Ametepe (2019) observed an exacerbation of the risk of poverty in relation to housing costs. The SOHOME (SOcial housing and HOMElessness) project pursues research questions related to individuals who are experiencing housing difficulties in Luxembourg, thereby drawing the current state-of-affairs as well as exploring potential solutions. Main questions are: (1) “What characterizes the concerned population in Luxembourg?”, (2) “How do social policies and social work respond to the identified issues?” and (3) “What are the main challenges of the social work in the field of homelessness and housing exclusion?” Through the qualitative design, several focus groups and interviews with social workers provide important insights to answer the research questions. Probably the largest proportion of homelessness services across Europe consists of low-threshold services that provide basic support outside of the housing sector or emergency/temporary accommodation. In contrast, services that immediately provide homeless people with a permanent home are only present to a certain extent in most countries (Pleace, Baptista, Benjaminsen & Busch-Geertsema, 2018). The SOHOME project targets various social services, from the emergency accommodation to the municipal social welfare office. The results from the discussions with social workers acting in the municipal social welfare offices show how great the demand for social and affordable living room is and how present forms of housing exclusion as well as solution-focused strategies are. [less ▲]

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See detailDevelopment of a Decision Support System for Incorporating Risk Assessments during the System Design of Microsatellites
Pandi Perumal, Raja UL

Doctoral thesis (2021)

The primary purpose of this research is to develop a decision support system for the early design of an optimal and reliable satellite while making the overall conceptual design process more efficient ... [more ▼]

The primary purpose of this research is to develop a decision support system for the early design of an optimal and reliable satellite while making the overall conceptual design process more efficient. Generally, a satellite design process begins with a mission definition followed by the functional design of the satellite system. Beyond this, the design goes through several iterations and eventually results in a detailed satellite system design. Only then does it make sense to feed in the piece-part information to estimate the reliability of the entire satellite system. Predicted reliability from this bottom-up method may sometimes be markedly lower than the requirements. In such case, the maturity of the design is brought down, and mitigation strategies need to be implemented to meet the reliability requirements. Consequently, introducing new or redundant parts as a mitigation approach can violate the previously satisfied requirements such as mass, power and cost. Furthermore, additional design iterations are needed until all the requirements are met. Therefore, this design approach is expensive, inefficient, and can be avoided if reliability is considered from the early design phase. However, the challenge is to simultaneously perform reliability analysis and system design as they are entirely different engineering disciplines. In this research, a decision support system: DESIRA is developed to bridge the gap between these two engineering disciplines and incorporate reliability assessments during the early design phase, thus resulting in a truly optimal satellite design. With its unique features such as Reliability Allocation, Reliability Growth, Multidisciplinary Design Optimization and Reliability-Based Multidisciplinary Design Optimization, DESIRA effectively aids the system design at each maturity level. [less ▲]

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See detailMuseum Meaning-making: Experience Design for Digital Cultural Heritage
Morse, Christopher UL

Doctoral thesis (2021)

Interactive technologies have created a ubiquity of digital arts and culture on the Web, offering visitors unprecedented access to museums around the world directly from their personal devices. Despite ... [more ▼]

Interactive technologies have created a ubiquity of digital arts and culture on the Web, offering visitors unprecedented access to museums around the world directly from their personal devices. Despite the enormous potential of these systems to facilitate education, cultural mediation, entertainment, or even interpersonal connection, research has demonstrated that users have difficulties deriving meaningful experiences from the digital museum visit due to a poor or incongruent user experience (UX). Among these challenges are a lack of integration between the online and on-site visit, as well as a disconnect from human-centered and participatory design methodologies increasingly embraced by contemporary museological practice. Insofar as museums are spaces of meaning-making, whether through aesthetic experiences, historical embodiment, or other phenomena, developing a deeper understanding of meaning and its implications for experience design in museum contexts may enhance the UX of museum technologies, particularly for the Web. Meaning has recently become an important conceptual focus of research in human-computer interaction (HCI), but additional work is necessary to connect theoretical advances in meaning-making to the cultural sector and to translate them into actionable design recommendations, which are the primary aims of the present work. This dissertation reports on five mixed-methods studies that address notions of meaningful design across three interrelated dimensions of UX analysis — the user, the system, and the context. For the purposes of this research, these dimensions have been adapted to the museum experience, thus becoming the (digital) visitor, (digital) cultural heritage, and the (digital) visit, respectively. The collection of studies contributes to a deeper understanding of meaning in and around museums through an analysis of museum memories, emerging information behaviors, public co-creation of digital technologies, and experience design strategies to bridge the on-site and online visit. While each study investigates individual facets of meaningful interaction between museums and their visitors, taken together they establish a fundamental interrelation, orienting designers and cultural professionals to embrace them as a coherent whole. The five studies presented in this work address individual dimensions of museum meaning and conclude with a framework of meaning to support museum experience design (MXD). The initial study provides insight on the (digital) visitor through an analysis of casual leisure information behaviors during navigation of an exploratory museum collections interface called rich-prospect (N = 30). The second is a co-creation study (N = 12) that introduces meaningful interaction through the design space of digital cultural heritage. The third study documents the #MuseumAtHome movement that emerged during the global COVID-19 pandemic, providing insights on meaningful design for the (digital) visit by integrating the on-site and online contexts. Finally, the fourth study combines an experience narrative analysis (N = 32) and a subsequent validation study (N = 354) on museum memories to establish a systematic understanding of the content of meaningful interaction in museums. This dissertation advances theory and practice in HCI by extending research on the psychology of meaningful interaction into a largely novel context, museum experience design. Each study contributes to a deeper understanding of the different facets of museum meaning-making and their relation to experience design, while the aggregate lays the groundwork for an integrated approach. The primary findings include new insights into the psychological factors of meaning in museum contexts, subsequent design recommendations for the online and on-site visit, and a suite of tools to support meaningful design in the cultural sector. [less ▲]

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See detailUhlmann fidelity and fidelity susceptibility for integrable spin chains at finite temperature: exact results
Białończyk, Michał; Gomez-Ruiz, Fernando Javier; Del Campo Echevarria, Adolfo UL

in New Journal of Physics (2021)

We derive the exact expression for the Uhlmann fidelity between arbitrary thermal Gibbs states of the quantum XY model in a transverse field with finite system size. Using it, we conduct a thorough ... [more ▼]

We derive the exact expression for the Uhlmann fidelity between arbitrary thermal Gibbs states of the quantum XY model in a transverse field with finite system size. Using it, we conduct a thorough analysis of the fidelity susceptibility of thermal states for the Ising model in a transverse field.We compare the exact results with a common approximation that considers only the positive-parity subspace, which is shown to be valid only at high temperatures. The proper inclusion of the odd parity subspace leads to the enhancement of maximal fidelity susceptibility in the intermediate range of temperatures. We show that this enhancement persists in the thermodynamic limit and scales quadratically with the system size. The correct low-temperature behavior is captured by an approximation involving the two lowest many-body energy eigenstates, from which simple expressions are obtained for the thermal susceptibility and specific heat. [less ▲]

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See detailMarina Hands : une actrice ensorcelée et ensorcelante ?
Deregnoncourt, Marine UL

in Deregnoncourt, Marine (Ed.) Sorcières, êtes-vous là ?. Femmes des lumières et de l'ombre. Rencontres de Mix-Cité (2021, September 23)

Pour tenter de contribuer humblement au propos de ce colloque intitulé : « Femmes des lumières et de l'ombre. Sorcières, êtes-vous là ? », nous entendons nous intéresser à l’actrice franco-britannique ... [more ▼]

Pour tenter de contribuer humblement au propos de ce colloque intitulé : « Femmes des lumières et de l'ombre. Sorcières, êtes-vous là ? », nous entendons nous intéresser à l’actrice franco-britannique Marina Hands. Fille de la comédienne Ludmila Mikaël et du metteur en scène shakespearien Terry Hands (tout récemment décédé), Marina Hands a dû faire preuve d’audace pour parvenir à faire entendre sa voix sur la scène française. Son corps et son timbre de voix, elle arrive justement à les imposer via des personnages féminins forts et combatifs qui choisissent de séduire et de s’abandonner. Pour tenter de le démontrer, nous envisageons de nous focaliser sur Aricie (dans la mise en scène de Patrice Chéreau de Phèdre de Jean Racine, Théâtre de l’Odéon, 2003) et Ysé (dans la mise en scène d’Yves Beaunesne de Partage de midi de Paul Claudel, Comédie-Française, 2007 et Théâtre Marigny, 2009 et 2020), car ce sont les deux héroïnes constitutives de notre corpus de thèse de doctorat. En quoi l’incarnation de Marina Hands rapproche-t-elle ces personnages féminins des figures de sorcières et / ou de magiciennes ? Comment l’interprétation de Marina Hands met-elle au jour la transe et la possession de ces protagonistes ? Qu’est-ce qui, in fine, fait la spécificité de cette comédienne ? Nous est-il seulement permis de la définir, cette singularité ? C’est précisément à ces questions auxquelles nous entendons répondre par le biais de cette communication. [less ▲]

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See detailMetascience: Disrupting the status quo or perpetuating inequities
Kozlowski, Diego UL

Scientific Conference (2021, September 23)

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See detailDyPS: Dynamic, Private and Secure GWAS (Summary) - GenoPri'21 Talk
Pascoal, Túlio UL; Decouchant, Jérémie; Boutet, Antoine et al

Presentation (2021, September 22)

Genome-Wide Association Studies (GWAS) identify the genomic variations that are statistically associated with a particular phenotype (e.g., a disease). GWAS results, i.e., statistics, benefit research and ... [more ▼]

Genome-Wide Association Studies (GWAS) identify the genomic variations that are statistically associated with a particular phenotype (e.g., a disease). GWAS results, i.e., statistics, benefit research and personalized medicine. The confidence in GWAS increases with the number of genomesanalyzed, which encourages federated computations where biocenters periodically include newly sequenced genomes. However, for legal and economical reasons, this collaboration can only happen if a release of GWAS results never jeopardizes the genomic privacy of data donors, if biocenters retain ownership and cannot learn each others’ data. Furthermore, given the reduced cost of sequencing DNA nowadays, there is now a need to update GWAS results in a dynamic manner, while enabling donors to withdraw consent at any time. Therefore, two challenges need to be simultaneously addressed to enable federated and dynamic GWAS: (i) the computation of GWAS statistics must rely on secure and privacy-preserving methods; and (ii) GWAS results that are publicly released should not allow any form of privacy attack. In this talk, we will introduce the problem we consider in more detail and present DyPS, the framework we have designed and recently presented at the Privacy Enhancing Technologies Symposium (PETS). We refer the reader to the full paper1 for the details we cannot cover in this short version. [less ▲]

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See detailIntertwining distant reading of web archives and oral histories of the COVID crisis
Schafer, Valerie UL

Scientific Conference (2021, September 22)

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See detailQuantum transport in topological condensed matter systems
Ekström, Carl Johan Ingvar UL

Doctoral thesis (2021)

Topology in condensed matter physics is a field that has exploded in the last two decades. With the realization of its importance, some previously unexplained observations can now be explained. With the ... [more ▼]

Topology in condensed matter physics is a field that has exploded in the last two decades. With the realization of its importance, some previously unexplained observations can now be explained. With the progress of time, many new topological phases of matter have been discovered, and topological materials have been shown to be fairly common in nature. Topological materials have further been shown to have properties that may be extremely useful for new technologies, such as spintronics and fault-tolerant quantum computation. The field is however, still evolving, and many properties of these materials are still unknown. In this thesis, we investigate how some of these types of materials react to applied external fields and the theories that can explain these observations. First, we investigate systems of coupled Majorana bound states. More specifically, we focus on the transport properties of the Majorana box and the T-junction in the presence of charging effects, overlap between the Majorana bound states, and multiple terminals connected to the system. To obtain the transport properties, we apply a master equation and calculate the current through the systems as biases are applied to the different terminals. By tuning the gate voltage, the transport is investigated in both the regime where sequential tunneling is dominating as well as the Coulomb blockaded regime, where cotunneling is the leading transport process. When sequential tunneling is dominating, the transport is mediated by both single electrons tunneling as well as processes that involve the creation and annihilation of Cooper pairs. In the Coulomb blockaded regime, transport is driven by cotunneling processes by transitions via virtual states. The results here show that four-terminal measurements can be a useful tool to characterize the properties of Majorana bound states with finite overlap and charging energy. Secondly, we study the optical activity of tilted nodal loop semimetals. The inherent Hall conductivity of topological materials makes the Kerr effect an excellent tool for investigating their properties. Here we first calculate the full conductivity tensor for a tilted nodal loop semimetal, where the tilt is in the $ k_{x} - k_{y} $ plane. The conductivity tensor allows us to calculate the Kerr effect. We study this both for a thin film and a bulk material and we fin, in general, that the Kerr effect is large, similar to other topological materials. Finally, we investigate electronic hydrodynamics in anomalous Hall insulators. First we derive the Navier-Stokes equations for topological materials and show that they are modified due to the Berry curvature. Secondly, we consider the flow in a narrow channel and the application of a small electric field. In this case, the Hall current can be neglected since it is much smaller than the longitudinal current. Flow in narrow channels conventionally leads to Poiseuille flow. However, as shown, the Berry curvature modifies the flow profile and shifts the maximum of the current profile towards one of the edges. Thirdly, we study the flow in an infinite geometry. In this case, it is shown that the Berry curvature induces whirlpools as well as causing an asymmetry in the profile of the electrical potential. Experimentally this can be observed by measuring the non-local resistance. [less ▲]

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See detailExperimental evaluation of RF waveform designs for Wireless Power Transfer using Software Defined Radio
Gautam, Sumit UL; Kumar, Sumit UL; Chatzinotas, Symeon UL et al

in IEEE Access (2021), 9

The possibility to harvest energy from ambient radio-frequency (RF) sources has intrigued humankind for the past several decades. In this context, there has been a tremendously growing research interest ... [more ▼]

The possibility to harvest energy from ambient radio-frequency (RF) sources has intrigued humankind for the past several decades. In this context, there has been a tremendously growing research interest in the field of wireless power transfer (WPT) using the RF range of the electromagnetic (EM) spectrum. In this paper, we experimentally investigate the aspect of real-time energy harvesting (EH) via different types of waveform designs such as orthogonal frequency division multiplexing (OFDM), square, triangular, sinusoidal, and sawtooth. We make use of a Software Defined Radio (SDR) and a Powercast P21XXCSR-EVB EH module to carry out the experiments on a practical device to assess performance. Specifically, we are interested in obtaining some insights based on the comparison between the aforementioned waveform designs from the perspectives of the separation distance between the USRP and P21XXCSR-EVB EH module, and power emission via USRP. In this vein, we perform additional subsequent experiments after reporting the practical effectiveness of the OFDM waveform, which also follows our intuitive analysis. Correspondingly, we study the effect on WPT with variable USRP transmit power, the separation distance between the USRP and EH antennas, number of OFDM sub-carriers, and multipath setting. As an application of OFDM, the effectiveness of fifth generation-new radio (5G-NR) and long-term evolution (LTE) waveforms are also tested for the WPT mechanism. The demonstration of the EH is provided in terms of the above-mentioned investigation metrics while seeking the best waveform to support WPT. [less ▲]

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See detailPresenter: Towards a Digital Oral History Database in Luxembourg
Venken, Machteld UL

Presentation (2021, September 22)

Detailed reference viewed: 15 (1 UL)
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See detailThe Experience of Security in Human-Computer Interactions: Understanding Security Perceptions Through the Concept of User Experience
Distler, Verena UL

Doctoral thesis (2021)

In traditional interactions that do not rely on technology, most people are able to assess risks to their privacy and security and understand how to mitigate these risks. However, risk assessment and ... [more ▼]

In traditional interactions that do not rely on technology, most people are able to assess risks to their privacy and security and understand how to mitigate these risks. However, risk assessment and mitigation is more challenging when interacting with technology, and people’s perceptions of security and privacy risks are not always aligned with reality. It is important for those who design technologies to understand how people perceive the security of technologies in order to avoid having their designs contribute to erroneous perceptions. Instead, interactions with technology should be deliberately designed to ensure that people do not over- or underestimate the security provided by the system. This dissertation contributes to a better understanding of users’ perceptions of security in human-computer interactions. It investigates which factors induce a perception of security and privacy risks and how user-centered design can influence these factors to deliberately design for or against perceived security. I use a mixed-methods approach to address these objectives, including a systematic literature review, empirical data collection with focus groups, expert co-creation sessions, user tests in a controlled environment and a quantitative survey experiment. The first research objective is to analyze how security and privacy researchers induce a perception of security and privacy risks with research participants. We conducted a systematic literature review and focused our analysis on study methods; risk representation; the use of prototypes, scenarios, and educational interventions; the use of deception to simulate risk; and types of participants. We discuss benefits and shortcomings of the methods, and identify key methodological, ethical, and research challenges when representing and assessing security and privacy risk. We also provide guidelines for the reporting of user studies in security and privacy. The second research objective is to explore the factors that contribute to the acceptance of privacy and security risks in situations where people need to weigh the potential advantages of a technology against its associated privacy or security risks. We conducted a series of focus groups and highlighted the reasons why people accept compromises to their privacy and security, finding that perceived usefulness and the fulfilment of the psychological needs for autonomy and control were important factors. Our results suggest potential links between technology acceptance models and user experience models in the context of privacy-relevant interactions. The third research objective is to design and evaluate examples of visible representations of security mechanisms, with a focus on encryption. We studied the effects of these visual and textual representations empirically to understand the impact of these visible security mechanisms on user experience, perceptions of security and users’ understanding of encryption. We addressed this question in a series of studies, both lab studies and online experiments. In a vignette experiment, we find that more complex descriptions of encryption can lead to a better understanding and higher perceived security when designed carefully. However, we find no effect of novel visualizations of encryption on user experience (UX), perceived security or understanding of encryption. The fourth objective is to explore how we might make the link from subjective experience to more secure behaviors. We introduce a new framework of security-enhancing friction design. The framework suggests helping users behave more securely by designing for moments of negative UX in security-critical situations while also ensuring that overall UX remains at an acceptable level to avoid disuse of secure technologies. Overall, this doctoral dissertation contributes to research in the field of human-computer interaction, and more specifically, usable privacy and security. It improves our understanding of the methods used by researchers in the field of usable privacy and security use to create a perception of risk, and the factors that make people accept or reject certain privacy trade-offs. This dissertation also makes contributions to helping researchers and creators of technology understand how their designs influence perceptions of security, UX and understanding of encryption. This enables them to design for or against a perception of security, depending on the actual level of security provided by the technology. Finally, we conceptualize security-enhancing friction, a framework that suggests helping users to behave more securely by designing for moments of negative UX. [less ▲]

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See detailLE PROJET RECTEC+, l’intérêt pour les compétences transversales par les partenaires stratégiques - Partie présentation du Luxembourg
Lejot, Eve UL

Scientific Conference (2021, September 21)

La matrice de compétences transversales du référentiel RECTEC+ devient donc un objet que nous devons nous approprier pour créer des niveaux 4-5-6-7 et pourquoi pas 8. Notre public d’étudiants en mobilité ... [more ▼]

La matrice de compétences transversales du référentiel RECTEC+ devient donc un objet que nous devons nous approprier pour créer des niveaux 4-5-6-7 et pourquoi pas 8. Notre public d’étudiants en mobilité et son besoin d’identifier les prérequis et les « à acquérir » nous engage(nt) à interroger l’existant en termes de matrice. Une fois ce travail réalisé au cours de la première rencontre avec les étudiants en désir de mobilité. Nous pourrons alors valider ou non les compétences désignées au vu des réactions du public cible. La valeur ajoutée de ce système est de reconnaître les compétences avant et après la mobilité à l’Université du Luxembourg et aussi dans les universités de France, de Belgique et d’Allemagne. [less ▲]

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See detailFinite-Alphabet Symbol-Level Multiuser Precoding for Massive MU-MIMO Downlink
Haqiqatnejad, Alireza UL; Kayhan, Farbod; Shahram, ShahbazPanahi et al

in IEEE Transactions on Signal Processing (2021), 69

We propose a finite-alphabet symbol-level precoding technique for massive multiuser multiple-input multiple-output (MU-MIMO) downlink systems which are equipped with finite-resolution digital-to-analog ... [more ▼]

We propose a finite-alphabet symbol-level precoding technique for massive multiuser multiple-input multiple-output (MU-MIMO) downlink systems which are equipped with finite-resolution digital-to-analog converters (DACs) of any precision. Using the idea of constructive interference (CI), we adopt a max-min fair design criterion which aims to maximize the minimum instantaneous received signal-to-noise ratio (SNR) among the user equipments (UEs) while ensuring a CI constraint for each UE under the restriction that the output of the precoder is a vector with finite-alphabet discrete elements. Due to this latter constraint, the design problem is an NP-hard quadratic program with discrete variables, and hence, is difficult to solve. In this paper, we tackle this difficulty by reformulating the problem in several steps into an equivalent continuous-domain biconvex form, including equivalent representations for discrete and binary constraints. Our final biconvex reformulation is obtained via an exact penalty approach and can efficiently be solved using a standard cyclic block coordinate descent algorithm. We evaluate the performance of the proposed finite-alphabet precoding design for DACs with different resolutions, where it is shown that employing low-resolution DACs can lead to higher power efficiencies. In particular, we focus on a setup with one-bit DACs and show through simulation results that compared to the existing schemes, the proposed design can achieve SNR gains of up to 2 dB. We further provide analytic and numerical analyses of complexity and show that our proposed algorithm is computationally efficient as it typically needs only a few tens of iterations to converge. [less ▲]

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See detailExploring the History of Digital History
Zaagsma, Gerben UL

Scientific Conference (2021, September 20)

As long as new preservation technologies and computing machines have been developed, the question of their utility and uptake in historical research practices has been debated. Yet, the very fact that ... [more ▼]

As long as new preservation technologies and computing machines have been developed, the question of their utility and uptake in historical research practices has been debated. Yet, the very fact that historical knowledge production has always been affected by new and emerging technologies is often forgotten. Similarly, the fact that key epistemological and methodological questions in what we now call ‘digital history’ were already debated decades ago by earlier generations of computing historians (analog and digital) is often overlooked. There is a lack of transmission of accumulated knowledge from the past and it sometimes seems as if every new generation of historians rediscovers the promise of ‘digital history’, with all of its attending hopes, visions and ambitions for reinventing and reshaping historical research. To fill this gap, this paper will explore what a history of digital history might look like. It will do so by focusing on hybridity as a key characteristic of historical research. Hybridity, seen as some form of integrating newly emerging tools, technologies, materials, and/or practices in historical research, has a long history that predates the advent of computers. In my paper I will map and qualify that history according to the main phases of historical research. The paper will conclude by outlining what groundwork is necessary to explore digital history’s forgotten roots: a basic overview of the field’s different spatio-temporal and ideological trajectories and recreation of the networks of computing historians in the pre-PC and early PC period. [less ▲]

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See detailCommunication Algorithms for 5G Internet of Things Systems via Satellites
Kodheli, Oltjon UL

Doctoral thesis (2021)

Detailed reference viewed: 94 (22 UL)