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See detailAlternative Object Use in Adults and Children: Embodied Cognitive Bases of Creativity
Gubenko, Alla UL; Houssemand, Claude UL

in Frontiers in Psychology (2022)

Why does one need creativity? On a personal level, improvisation with available resources is needed for online coping with unforeseen environmental stimuli when existing knowledge and apparent action ... [more ▼]

Why does one need creativity? On a personal level, improvisation with available resources is needed for online coping with unforeseen environmental stimuli when existing knowledge and apparent action strategies do not work. On a cultural level, the exploitation of existing cultural means and norms for the deliberate production of novel and valuable artifacts is a basis for cultural and technological development and extension of human action possibilities across various domains. It is less clear, however, how creativity develops and how exactly one arrives at generating new action possibilities and producing multiple alternative action strategies using familiar objects. In this theoretical paper, we first consider existing accounts of the creative process in the Alternative Uses Task and then present an alternative interpretation, drawing on sociocultural views and an embodied cognition approach. We explore similarities between the psychological processes underlying the generation of new uses in the Alternative Uses Task and children’s pretend play. We discuss possible cognitive mechanisms and speculate how the generation of new action possibilities for common objects in pretend play can be related to adults’ ability to generate new action strategies associated with object use. Implications for creativity development in humans and embodied artificial agents are discussed. [less ▲]

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See detailModel-based valuation of smart grid initiatives: Foundations, open issues, requirements, and a research outlook
de Kinderen, Sybren; Kaczmarek-Heß, Monika; Ma, Qin UL et al

in Data and Knowledge Engineering (2022), 141

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See detailDefeating Super-Reactive Jammers With Deception Strategy: Modeling, Signal Detection, and Performance Analysis
Van Huynh, Nguyen; Nguyen, Diep N.; Thai Hoang, Dinh et al

in IEEE Transactions on Wireless Communications (2022), 21(9), 7374-7390

This paper develops a novel framework to defeat a super-reactive jammer, one of the most difficult jamming attacks to deal with in practice. Specifically, the jammer has an unlimited power budget and is ... [more ▼]

This paper develops a novel framework to defeat a super-reactive jammer, one of the most difficult jamming attacks to deal with in practice. Specifically, the jammer has an unlimited power budget and is equipped with the self-interference suppression capability to simultaneously attack and listen to the transmitter’s activities. Consequently, dealing with super-reactive jammers is very challenging. Thus, we introduce a smart deception mechanism to attract the jammer to continuously attack the channel and then leverage jamming signals to transmit data based on the ambient backscatter communication technology. To detect the backscattered signals, the maximum likelihood detector can be adopted. However, this method is notorious for its high computational complexity and requires the model of the current propagation environment as well as channel state information. Hence, we propose a deep learning-based detector that can dynamically adapt to any channels and noise distributions. With a Long Short-Term Memory network, our detector can learn the received signals’ dependencies to achieve a performance close to that of the optimal maximum likelihood detector. Through simulation and theoretical results, we demonstrate that with our approaches, the more power the jammer uses to attack the channel, the better bit error rate performance the transmitter can achieve. [less ▲]

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See detailBenchmarking of univariate pleiotropy detection methods applied to epilepsy
Adesoji, Oluyomi M.; Schulz, Herbert; May, Patrick UL et al

in Human Mutation (2022), 43(9), 1314-1332

AbstractPleiotropy is a widespread phenomenon that may increase insight into the etiology of biological and disease traits. Since genome-wide association studies frequently provide information on a single ... [more ▼]

AbstractPleiotropy is a widespread phenomenon that may increase insight into the etiology of biological and disease traits. Since genome-wide association studies frequently provide information on a single trait only, only univariate pleiotropy detection methods are applicable, with yet unknown comparative performance. Here, we compared five such methods with respect to their ability to detect pleiotropy, including meta-analysis, ASSET, cFDR, CPBayes, and PLACO, by performing extended computer simulations that varied the underlying etiological model for pleiotropy for a pair of traits, including the number of causal variants, degree of traits’ overlap, effect sizes as well as trait prevalence, and varying sample sizes. Our results indicate that ASSET provides the best trade-off between power and protection against false positives. We then applied ASSET to a previously published ILAE consortium dataset on complex epilepsies, comprising genetic generalized epilepsy and focal epilepsy cases and corresponding controls. We identified a novel candidate locus at 17q21.32 and confirmed locus 2q24.3, previously identified to act pleiotropically on both epilepsy subtypes by a mega-analysis. Functional annotation, tissue-specific expression and regulatory function analysis as well as Bayesian co-localization analysis corroborated this result, rendering 17q21.32 a worthwhile candidate for follow-up studies on pleiotropy in epilepsies.This article is protected by copyright. All rights reserved. [less ▲]

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See detailRF Precoding for Cognitive Radio Systems
Tsinos, Christos UL; Chatzinotas, Symeon UL; Ottersten, Björn UL

in IEEE Wireless Communications Letters (2022), 11(9), 1845-1849

In this letter, a precoding framework in the radio-frequency (RF) domain is developed for the downlink of a multiuser multiple-input single-output underlay cognitive radio (CR) system. Firstly, a low ... [more ▼]

In this letter, a precoding framework in the radio-frequency (RF) domain is developed for the downlink of a multiuser multiple-input single-output underlay cognitive radio (CR) system. Firstly, a low hardware complexity analog multiantenna architecture is proposed for the system’s transmitter. The proposed analog architecture is based on a phase-shifting network driven by an variable gain amplifier and has low power consumption since it avoids the use of energy hungry components such as digital-to-analog converters (DACs). Secondly, a novel RF precoder for the design of the transmit signals is developed such that the performance of the CR system is optimized and the constraints related to both the system’s architecture and the employed underlay CR paradigm are satisfied. The corresponding nonconvex and difficult optimization problem is formulated and solved via a novel algorithmic solution based on the saddle point method. The convergence of the proposed algorithmic solution is theoretically studied. The proposed approach is shown to be much more energy efficient than existing approaches based on fully digital transceivers. [less ▲]

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See detailEnergy-Efficient IRS-Aided NOMA Beamforming for 6G Wireless Communications
Ihsan, Asim; Chen, Wen; Asif, Muhammad et al

in IEEE Transactions on Green Communications and Networking (2022)

This manuscript presents an energy-efficient alternating optimization framework based on intelligent reflective surfaces (IRS) aided non-orthogonal multiple access beamforming (NOMA-BF) system for 6G ... [more ▼]

This manuscript presents an energy-efficient alternating optimization framework based on intelligent reflective surfaces (IRS) aided non-orthogonal multiple access beamforming (NOMA-BF) system for 6G wireless communications. Specifically, this work proposes a centralized IRS-enabled design for the NOMA-BF system to optimize the active beamforming and power allocation coefficient (PAC) of users at the transmitter in the first stage and passive beamforming at IRS in the 2nd stage to maximize the energy efficiency (EE) of the network. However, an increment in the number of supportable users with the NOMA-BF system will lead to NOMA user interference and inter-cluster interference (ICI). To mitigate the effect of ICI, first zero-forcing beamforming along with efficient user clustering algorithm is exploited and then NOMA user interference is tackled efficiently through a proposed iterative algorithm that computes PAC of NOMA user through simplified closed-form expression under the required system constraints. In the 2nd stage, the problem of passive beamforming is solved through a technique based on difference-of-convex (DC) programming and successive convex approximation (SCA). Simulation results demonstrate that the proposed alternating framework for energy-efficient IRS-assisted NOMA-BF system can achieve convergence within a few iterations and provide efficient performance in terms of EE of the system with low complexity. [less ▲]

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See detailWho benefits from air service agreements? The case of international air cargo operations
Wu, You UL; Lange, Anne UL; Mantin, Benny UL

in Transportation Research Part B: Methodological (2022), 163

Air service agreements between countries spell out diverse provisions, such as reciprocal capacity allocations. We analyze how such agreements, which regulate total capacity in markets, affect total ... [more ▼]

Air service agreements between countries spell out diverse provisions, such as reciprocal capacity allocations. We analyze how such agreements, which regulate total capacity in markets, affect total welfare and its distribution. We consider the interactions between two competing cargo airlines, their end customers, logistics service providers—who serve as intermediaries between the former two agent types—as well as the policy makers. Accounting for demand uncertainty, we model this interaction as a two-stage game. In the first stage, the policy makers coordinate equal capacity allocations to the two asset providers, whereas in the second stage, the asset providers compete over prices in the spot market. Solving the model, we characterize the pricing strategies employed by the two competing capacity-constrained asset providers in the spot market when facing price sensitive demand from end customers. We further analyze the corresponding capacity decisions. We then compare this coordinated competitive setting with a collaborative setting where the two asset providers can (virtually) merge and act as a monopoly. We find that, compared with the monopoly setting, the coordinated duopoly results in lower capacity, lower profits to the asset providers, larger benefits to both end customers and logistics service providers, and overall lower total welfare. These results suggest that policy makers shall hold an open attitude towards a higher level of cooperation among the asset providers. We carry out robustness checks to verify our insights hold with three, rather than two, asset providers, with different demand distributions, when capacity is costly and when asymmetric capacities are allowed in the spot market. [less ▲]

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See detailOptimal strategy for multiple-phase estimation under practical measurement with multimode NOON states
Ur Rehman, Junaid UL; Hong, Seongjin; Lee, Seung-Woo et al

in Physical Review. A. (2022), 106

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See detailUse of assistive technologies and alternative means by older people: The “Actional Model of Older people´s Coping with Health-Related Declines”
Abri, Diana UL; Boll, Thomas UL

in Integrative Psychological and Behavioral Science (2022)

This paper presents the “Actional Model of Older people´s Coping with Health-Related Declines” to explain the use of a broad range of action alternatives of older persons for dealing with current or ... [more ▼]

This paper presents the “Actional Model of Older people´s Coping with Health-Related Declines” to explain the use of a broad range of action alternatives of older persons for dealing with current or anticipated diseases, functional declines, activity limitations and participation restrictions. The general background is the action-theoretical model of intentional self-regulation of human development (e.g., Brandtstädter, 2006; Rothermund & Brandtstädter, 2019). Yet, our model provides an increased specification of major model components toward the situation of older people coping with current or anticipated health-related declines. The model development follows an adapted theory construction methodology (TCM) by Borsboom et al. (2021) and adapted principles for constructing practically useful theories by Berkman & Wilson (2021). Regarding content, we further draw on models of the use of assistive technologies (ATs) and medical services, qualitative studies on reasons for using ATs, and quantitative studies on health-related goals. The resulting model includes these components: (1) Discrepancies between perceived or anticipated and desired health-related development, (2) health-related discrepancy reduction and prevention goals, (3) action possibilities for reducing or preventing health-related discrepancies, (4) further motivating and demotivating goals, (5) beliefs about effective means for reaching the goals (2) and (4), (6) generation of the particular coping actions by goals (2) and (4) in combination with beliefs about effective means, (7) external context factors, and (8) modes of joint decision-making and decision-making on behalf of older people. The explanatory and practical value of the model are discussed as well as its implications for future research and geropsychology teaching. [less ▲]

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See detailTaxes and declared profits: evidence from gold mines in Africa
Zanaj, Skerdilajda UL; Bourgain, Arnaud UL; Zanaj, Skerdilajda UL

in Resources Policy (2022), 78

In this paper, we analyze the effects of tax changes on the declared profits of extractive firms. We consider a country that levies a profit tax and a royalty on the profits of extractive firms to ... [more ▼]

In this paper, we analyze the effects of tax changes on the declared profits of extractive firms. We consider a country that levies a profit tax and a royalty on the profits of extractive firms to maximize its tax revenues. Mining companies located in the country engage in overstating extractive costs to reduce their taxable income. We show that the higher taxes, the lower the declared profit. Then, we estimate the effect of the change of profit taxes and royalties on the extracting firms’ profit in African countries during the period spanning from 2007 to <br />2018. We employ the Mining Intelligence database to constitute an individual data panel of gold mines located in Sub-Saharan countries. Our empirical findings also suggest an inverse relationship between the tax rate change of the tax instruments and the declared profit of the firms. This link indicates that firms decide on how much profit to declare depending on the tax levels. [less ▲]

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See detailBirefringence-modulated total internal reflection in liquid crystal shells
Popov, Nikolay UL; Lagerwall, Jan UL

in Frontiers in Soft Matter (2022), 2(Summer), 991375

The combination of anisotropic boundary conditions and topological constraints acting on a spherical shell of nematic liquid crystal confined between aqueous phases gives rise to peculiar but well-defined ... [more ▼]

The combination of anisotropic boundary conditions and topological constraints acting on a spherical shell of nematic liquid crystal confined between aqueous phases gives rise to peculiar but well-defined configurations of the director field, and thus of the optic axis that defines the impact of the nematic birefringence. While the resulting optics of nematic shells has been extensively investigated in transmission, studies of the reflection behavior are scarce. Here we show that nematic shells exhibit specific light guiding paths mediated by birefringence-modulated total internal reflection (TIR) within the shell. With stabilizers promoting tangential boundary conditions, shells show immobile antipodal spots revealing the locations of maximum effective refractive index, but their intensity is modulated by the polarization of the illuminating light. With normal-aligning stabilizers, shells instead show bright arcs separated by dark spots, and these follow the rotation of the polarization of the illuminating light. Reflection polarizing microscopy thus offers a valuable complement to the more common characterization in transmission, adding data that can be helpful for accurately mapping out director fields in shells of any liquid crystal phase. Moreover, the TIR-mediated light guiding paths may offer interesting handles to localize photopolymerization of reactive liquid crystal shells or to dynamically modulate the response of light-triggered liquid crystal elastomer shell actuators. [less ▲]

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See detailConserved patterns across ion channels correlate with variant pathogenicity and clinical phenotypes
Brünger, Tobias; Pérez-Palma, Eduardo; Montanucci, Ludovica et al

in Brain: a Journal of Neurology (2022)

Clinically identified genetic variants in ion channels can be benign or cause disease by increasing or decreasing the protein function. Consequently, therapeutic decision-making is challenging without ... [more ▼]

Clinically identified genetic variants in ion channels can be benign or cause disease by increasing or decreasing the protein function. Consequently, therapeutic decision-making is challenging without molecular testing of each variant. Our biophysical knowledge of ion channel structures and function is just emerging, and it is currently not well understood which amino acid residues cause disease when mutated.We sought to systematically identify biological properties associated with variant pathogenicity across all major voltage and ligand-gated ion channel families. We collected and curated 3,049 pathogenic variants from hundreds of neurodevelopmental and other disorders and 12,546 population variants for 30 ion channel or channel subunits for which a high-quality protein structure was available. Using a wide range of bioinformatics approaches, we computed 163 structural features and tested them for pathogenic variant enrichment. We developed a novel 3D spatial distance scoring approach that enables comparisons of pathogenic and population variant distribution across protein structures.We discovered and independently replicated that several pore residue properties and proximity to the pore axis were most significantly enriched for pathogenic variants compared to population variants. Using our 3D scoring approach, we showed that the strongest pathogenic variant enrichment was observed for pore-lining residues and alpha-helix residues within 5Å distance from the pore axis center and not involved in gating. Within the subset of residues located at the pore, the hydrophobicity of the pore was the feature most strongly associated with variant pathogenicity. We also found an association between the identified properties and both clinical phenotypes and functional in vitro assays for voltage-gated sodium channels (SCN1A, SCN2A, SCN8A) and N-methyl-D-aspartate (NMDA) receptor (GRIN1, GRIN2A, GRIN2B) encoding genes. In an independent expert-curated dataset of 1,422 neurodevelopmental disorder pathogenic patient variants and 679 electrophysiological experiments, we show that pore axis distance is associated with seizure age of onset and cognitive performance as well as differential gain vs. loss-of-channel function.In summary, we identified biological properties associated with ion-channel malfunction and show that these are correlated with in vitro functional read-outs and clinical phenotypes in patients with neurodevelopmental disorders. Our results suggest that clinical decision support algorithms that predict variant pathogenicity and function are feasible in the future. [less ▲]

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See detailNumber transcoding in bilinguals—A transversal developmental study
Lachelin, Remy UL; Van Rinsveld, Amandine; Poncin, Alexandre et al

in PLoS ONE (2022), 17(8), 0273391

Number transcoding is the cognitive task of converting between different numerical codes (i.e. visual “42”, verbal “forty-two”). Visual symbolic to verbal transcoding and vice versa strongly relies on ... [more ▼]

Number transcoding is the cognitive task of converting between different numerical codes (i.e. visual “42”, verbal “forty-two”). Visual symbolic to verbal transcoding and vice versa strongly relies on language proficiency. We evaluated transcoding of German-French bilinguals from Luxembourg in 5th, 8th, 11th graders and adults. In the Luxembourgish educational system, children acquire mathematics in German (LM1) until the 7th grade, and then the language of learning mathematic switches to French (LM2). French `70s `80s `90s are less transparent than `30s `40s `50s numbers, since they have a base-20 structure, which is not the case in German. Transcoding was evaluated with a reading aloud and a verbal-visual number matching task. Results of both tasks show a cognitive cost for transcoding numbers having a base-20 structure (i.e. `70s, `80s and `90s), such that response times were slower in all age groups. Furthermore, considering only base-10 numbers (i.e. `30s `40s `50s), it appeared that transcoding in LM2 (French) also entailed a cost. While participants across age groups tended to read numbers slower in LM2, this effect was limited to the youngest age group in the matching task. In addition, participants made more errors when reading LM2 numbers. In conclusion, we observed an age-independent language effect with numbers having a base-20 structure in French, reflecting their reduced transparency with respect to the decimal system. Moreover, we find an effect of language of math acquisition such that transcoding is less well mastered in LM2. This effect tended to persist until adulthood in the reading aloud task, while in the matching task performance both languages become similar in older adolescents and young adults. This study supports the link between numbers and language, especially highlighting the impact of language on reading numbers aloud from childhood to adulthood. [less ▲]

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See detailRinging the bell for quality P.E.: What are the realities of remote physical education?
Kovacs, Viktoria; Csanyi, Tamas; Blagus, Rok et al

in European Journal of Public Health (2022), 32(Issue Supplement_1), 3843

Background To date, few data on the quality and quantity of online physical education (P.E.) during the COVID-19 pandemic have been published. We assessed activity in online classes and reported allocated ... [more ▼]

Background To date, few data on the quality and quantity of online physical education (P.E.) during the COVID-19 pandemic have been published. We assessed activity in online classes and reported allocated curriculum time for P.E. in a multi-national sample of European children (6–18 years). Methods Data from two online surveys were analysed. A total of 8395 children were included in the first round (May–June 2020) and 24 302 in the second round (January–February 2021). Results Activity levels during P.E. classes were low in spring 2020, particularly among the youngest children and in certain countries. 27.9% of students did not do any online P.E. and 15.7% were hardly ever very active. Only 18.4% were always very active and 14.9% reported being very active quite often. In winter 2020, we observed a large variability in the allocated curriculum time for P.E. In many countries, this was lower than the compulsory requirements. Only 65.7% of respondents had the same number of P.E. lessons than before pandemic, while 23.8% had less P.E., and 6.8% claimed to have no P.E. lessons. Rates for no P.E. were especially high among secondary school students, and in large cities and megapolises. Conclusions During the COVID-19 pandemic, European children were provided much less P.E. in quantity and quality than before the pandemic. Countermeasures are needed to ensure that these changes do not become permanent. Particular attention is needed in large cities and megapolises. The critical role of P.E. for students’ health and development must be strengthened in the school system. [less ▲]

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See detailEvaluation of SORL1 in Lewy Body Dementia Identifies No Significant Associations
Ray, Anindidta; Reho, Paolo; Shah, Zalak et al

in Movement Disorders (2022)

Lewy body dementia (LBD) is a clinically heterogeneous neurodegenerative disorder characterized by parkinsonism, visual hallucinations, fluctuating mental status, and rapid eye movement sleep behavior ... [more ▼]

Lewy body dementia (LBD) is a clinically heterogeneous neurodegenerative disorder characterized by parkinsonism, visual hallucinations, fluctuating mental status, and rapid eye movement sleep behavior disorder. LBD lies along a spectrum between Parkinson's disease and Alzheimer's disease, and recent evidence suggests that the genetic architectures of these age-related syndromes are intersecting. In summary, we did not find a significant enrichment of rare, damaging SORL1 mutations in our well-powered LBD cohort. Our data set is, to our knowledge, the largest genome-sequence cohort in this understudied disease. Although it is possible that an association was missed due to allelic heterogeneity, our findings indicate that caution should be exercised when interpreting SORL1 mutations in LBD, as the current evidence does not conclusively support an association with disease risk. [less ▲]

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See detailEnhanced Communications on Satellite-Based IoT Systems to Support Maritime Transportation Services
Monzon Baeza, Victor UL; Ortiz Gomez, Flor de Guadalupe UL; Herrero Garcia, Samuel et al

in Sensors (2022), 22(17),

Maritime transport has become important due to its ability to internationally unite all continents. In turn, during the last two years, we have observed that the increase of consumer goods has resulted in ... [more ▼]

Maritime transport has become important due to its ability to internationally unite all continents. In turn, during the last two years, we have observed that the increase of consumer goods has resulted in global shipping deadlocks. In addition, the future goes through the role of ports and efficiency in maritime transport to decarbonize its impact on the environment. In order to improve the economy and people’s lives, in this work, we propose to enhance services offered in maritime logistics. To do this, a communications system is designed on the deck of ships to transmit data through a constellation of satellites using interconnected smart devices based on IoT. Among the services, we highlight the monitoring and tracking of refrigerated containers, the transmission of geolocation data from Global Positioning System (GPS), and security through the Automatic Identification System (AIS). This information will be used for a fleet of ships to make better decisions and help guarantee the status of the cargo and maritime safety on the routes. The system design, network dimensioning, and a communications protocol for decision-making will be presented. [less ▲]

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See detailAlpha synuclein determines ferroptosis sensitivity in dopaminergic neurons via modulation of ether-phospholipid membrane composition.
Mahoney-Sanchez, Laura; Bouchaoui, Hind; Boussaad, Ibrahim UL et al

in Cell reports (2022), 40(8), 111231

There is a continued unmet need for treatments that can slow Parkinson's disease progression due to the lack of understanding behind the molecular mechanisms underlying neurodegeneration. Since its ... [more ▼]

There is a continued unmet need for treatments that can slow Parkinson's disease progression due to the lack of understanding behind the molecular mechanisms underlying neurodegeneration. Since its discovery, ferroptosis has been implicated in several diseases and represents a therapeutic target in Parkinson's disease. Here, we use two highly relevant human dopaminergic neuronal models to show that endogenous levels of α-synuclein can determine the sensitivity of dopaminergic neurons to ferroptosis. We show that reducing α-synuclein expression in dopaminergic neurons leads to ferroptosis evasion, while elevated α-synuclein expression in patients' small-molecule-derived neuronal precursor cells with SNCA triplication causes an increased vulnerability to lipid peroxidation and ferroptosis. Lipid profiling reveals that ferroptosis resistance is due to a reduction in ether-linked phospholipids, required for ferroptosis, in neurons depleted of α-synuclein (α-syn). These results provide a molecular mechanism linking α-syn levels to the sensitivity of dopaminergic neurons to ferroptosis, suggesting potential therapeutic relevance. [less ▲]

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See detailCoevaporation Stabilizes Tin-Based Perovskites in a Single Sn-Oxidation State
Singh, Ajay UL; Hieulle, Jeremy UL; Ferreira Machado, Joana Andreia UL et al

in Nano Letters (2022)

Chemically processed methylammonium tin-triiodide (CH3NH3SnI3) films include Sn in different oxidation states, leading to poor stability and low power conversion efficiency of the resulting solar cells ... [more ▼]

Chemically processed methylammonium tin-triiodide (CH3NH3SnI3) films include Sn in different oxidation states, leading to poor stability and low power conversion efficiency of the resulting solar cells (PSCs). The development of absorbers with Sn [2+] only has been identified as one of the critical steps to develop all Sn-based devices. Here, we report on coevaporation of CH3NH3I and SnI2 to obtain absorbers with Sn being only in the preferred oxidation state [+2] as confirmed by X-ray photoelectron spectroscopy. The Sn [4+]-free absorbers exhibit smooth highly crystalline surfaces and photoluminescence measurements corroborating their excellent optoelectronic properties. The films show very good stability under heat and light. Photoluminescence quantum yields up to 4 × 10^-3 translate in a quasi Fermi-level splittings exceeding 850 meV under one sun equivalent conditions showing high promise in developing lead-free, high efficiency, and stable PSCs. [less ▲]

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See detailEvolution of Non-Terrestrial Networks From 5G to 6G: A Survey
Azari, M. Mahdi; Solanki, Sourabh UL; Chatzinotas, Symeon UL et al

in IEEE Communications Surveys & Tutorials (2022), 24(4), 2633-2672

Non-terrestrial networks (NTNs) traditionally have certain limited applications. However, the recent technological advancements and manufacturing cost reduction opened up myriad applications of NTNs for ... [more ▼]

Non-terrestrial networks (NTNs) traditionally have certain limited applications. However, the recent technological advancements and manufacturing cost reduction opened up myriad applications of NTNs for 5G and beyond networks, especially when integrated into terrestrial networks (TNs). This article comprehensively surveys the evolution of NTNs highlighting their relevance to 5G networks and essentially, how it will play a pivotal role in the development of 6G ecosystem. We discuss important features of NTNs integration into TNs and the synergies by delving into the new range of services and use cases, various architectures, technological enablers, and higher layer aspects pertinent to NTNs integration. Moreover, we review the corresponding challenges arising from the technical peculiarities and the new approaches being adopted to develop efficient integrated ground-air-space (GAS) networks. Our survey further includes the major progress and outcomes from academic research as well as industrial efforts representing the main industrial trends, field trials, and prototyping towards the 6G networks. [less ▲]

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See detailRoadmap on Machine learning in electronic structure
H J Kulik; T Hammerschmidt; Tkatchenko, Alexandre UL

in IOP Conference Series: Materials Science and Engineering (2022)

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See detailMatching Traffic Demand in GEO Multibeam Satellites: The Joint Use of Dynamic Beamforming and Precoding Under Practical Constraints
Chaker, Haythem UL; Chougrani, Houcine UL; Alves Martins, Wallace UL et al

in IEEE Transactions on Broadcasting (2022)

To adjust for the non-uniform spatiotemporal nature of traffic patterns, next-generation high throughput satellite (HTS) systems can benefit from recent technological advancements in the space-segment in ... [more ▼]

To adjust for the non-uniform spatiotemporal nature of traffic patterns, next-generation high throughput satellite (HTS) systems can benefit from recent technological advancements in the space-segment in order to dynamically design traffic-adaptive beam layout plans (ABLPs). In this work, we propose a framework for dynamic beamforming (DBF) optimization and adaptation in dynamic environments. Given realistic traffic patterns and a limited power budget, we propose a feasible DBF operation for a geostationary multibeam HTS network. The goal is to minimize the mismatch between the traffic demand and the offered capacity under practical constraints. These constraints are dictated by the traffic-aware design requirements, the on-board antenna system limitations, and the signaling considerations in the K-band. Noting that the ABLP is agnostic about the inherent inter-beam interference (IBI), we construct an interference simulation environment using irregularly shaped beams for a large-scale multibeam HTS system. To cope with IBI, the combination of on-board DBF and on-ground precoding is considered. For precoded and non-precoded HTS configurations, the proposed design shows better traffic-matching capabilities in comparison to a regular beam layout plan. Lastly, we provide trade-off analyses between system-level key performance indicators for different realistic non-uniform traffic patterns. [less ▲]

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See detailGradient descent dynamics and the jamming transition in infinite dimensions
Manacorda, Alessandro UL; Zamponi, Francesco

in Journal of Physics. A, Mathematical and Theoretical (2022)

Gradient descent dynamics in complex energy landscapes, i.e. featuring multiple minima, finds application in many different problems, from soft matter to machine learning. Here, we analyze one of the ... [more ▼]

Gradient descent dynamics in complex energy landscapes, i.e. featuring multiple minima, finds application in many different problems, from soft matter to machine learning. Here, we analyze one of the simplest examples, namely that of soft repulsive particles in the limit of infinite spatial dimension d. The gradient descent dynamics then displays a jamming transition: at low density, it reaches zero-energy states in which particles' overlaps are fully eliminated, while at high density the energy remains finite and overlaps persist. At the transition, the dynamics becomes critical. In the d → ∞ limit, a set of self-consistent dynamical equations can be derived via mean field theory. We analyze these equations and we present some partial progress towards their solution. We also study the random Lorentz gas in a range of d = 2...22, and obtain a robust estimate for the jamming transition in d → ∞. The jamming transition is analogous to the capacity transition in supervised learning, and in the appendix we discuss this analogy in the case of a simple one-layer fully-connected perceptron. [less ▲]

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See detailConstruction of a digital fetus library for radiation dosimetry
Qu; Xie, Tianwu; L Giger et al

in Medical Physics (2022)

Purpose: Accurate estimations of fetal absorbed dose and radiation risks are crucial for radiation protection and important for radiological imaging research owing to the high radiosensitivity of the ... [more ▼]

Purpose: Accurate estimations of fetal absorbed dose and radiation risks are crucial for radiation protection and important for radiological imaging research owing to the high radiosensitivity of the fetus. Computational anthropomorphic models have been widely used in patient-specific radiation dosimetry calculations. In this work, we aim to build the first digital fetal library for more reliable and accurate radiation dosimetry studies. Acquisition and validation methods: Computed tomography (CT) images of abdominal and pelvic regions of 46 pregnant females were segmented by experienced medical physicists. The segmented tissues/organs include the body contour, skeleton, uterus, liver, kidney, intestine, stomach, lung, bladder, gall bladder, spleen, and pancreas for maternal body, and placenta, amniotic fluid, fetal body, fetal brain, and fetal skeleton. Nonuniform rational B-spline (NURBS) surfaces of each identified region was constructed manually using 3D modeling software. The Hounsfield unit values of each identified organs were gathered from CT images of pregnant patients and converted to tissue density. Organ volumes were further adjusted according to reference measurements for the developing fetus recommended by the World Health Organization (WHO) and International Commission on Radiological Protection. A series of anatomical parameters, including femur length, humerus length, biparietal diameter, abdominal circumference (FAC), and head circumference, were measured and compared with WHO recommendations. Data format and usage notes: The first fetal patient-specific model library was developed with the anatomical characteristics of each model derived from the corresponding patient whose gestational age varies between 8 and 35 weeks. Voxelized models are represented in the form of MCNP matrix input files representing the three-dimensional model of the fetus. The size distributions of each model are also provided in text files. All data are stored on Zenodo and are publicly accessible on the following link: https://zenodo.org/record/6471884. Potential applications: The constructed fetal models and maternal anatomical characteristics are consistent with the corresponding patients. The resulting computational fetus could be used in radiation dosimetry studies to improve the reliability of fetal dosimetry and radiation risks assessment. The advantages of NURBS surfaces in terms of adapting fetal postures and positions enable us to adequately assess their impact on radiation dosimetry calculations. [less ▲]

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See detailQuantum machine learning corrects classical forcefields: Stretching DNA base pairs in explicit solvent
Berryman, Josh UL; Taghavi, Amirhossein UL; Mazur, Florian UL et al

in Journal of Chemical Physics (2022), 157(6),

In order to improve the accuracy of molecular dynamics simulations, classical forcefields are supplemented with a kernel-based machine learning method trained on quantum-mechanical fragment energies. As ... [more ▼]

In order to improve the accuracy of molecular dynamics simulations, classical forcefields are supplemented with a kernel-based machine learning method trained on quantum-mechanical fragment energies. As an example application, a potential-energy surface is generalized for a small DNA duplex, taking into account explicit solvation and long-range electron exchange–correlation effects. A long-standing problem in molecular science is that experimental studies of the structural and thermodynamic behavior of DNA under tension are not well confirmed by simulation; study of the potential energy vs extension taking into account a novel correction shows that leading classical DNA models have excessive stiffness with respect to stretching. This discrepancy is found to be common across multiple forcefields. The quantum correction is in qualitative agreement with the experimental thermodynamics for larger DNA double helices, providing a candidate explanation for the general and long-standing discrepancy between single molecule stretching experiments and classical calculations of DNA stretching. The new dataset of quantum calculations should facilitate multiple types of nucleic acid simulation, and the associated Kernel Modified Molecular Dynamics method (KMMD) is applicable to biomolecular simulations in general. KMMD is made available as part of the AMBER22 simulation software. [less ▲]

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See detailOptimal Priority Assignment for Real-Time Systems: A Coevolution-Based Approach
Lee, Jaekwon UL; Shin, Seung Yeob UL; Nejati, Shiva et al

in Empirical Software Engineering (2022), 27

In real-time systems, priorities assigned to real-time tasks determine the order of task executions, by relying on an underlying task scheduling policy. Assigning optimal priority values to tasks is ... [more ▼]

In real-time systems, priorities assigned to real-time tasks determine the order of task executions, by relying on an underlying task scheduling policy. Assigning optimal priority values to tasks is critical to allow the tasks to complete their executions while maximizing safety margins from their specified deadlines. This enables real-time systems to tolerate unexpected overheads in task executions and still meet their deadlines. In practice, priority assignments result from an interactive process between the development and testing teams. In this article, we propose an automated method that aims to identify the best possible priority assignments in real-time systems, accounting for multiple objectives regarding safety margins and engineering constraints. Our approach is based on a multi-objective, competitive coevolutionary algorithm mimicking the interactive priority assignment process between the development and testing teams. We evaluate our approach by applying it to six industrial systems from different domains and several synthetic systems. The results indicate that our approach significantly outperforms both our baselines, i.e., random search and sequential search, and solutions defined by practitioners. Our approach scales to complex industrial systems as an offline analysis method that attempts to find near-optimal solutions within acceptable time, i.e., less than 16 hours. [less ▲]

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See detailRényi Entropy in Statistical Mechanics
Fuentes, Jesús UL; Goncalves, Jorge UL

in Entropy (2022), 24(8), 1080

Rényi entropy was originally introduced in the field of information theory as a parametric relaxation of Shannon (in physics, Boltzmann–Gibbs) entropy. This has also fuelled different attempts to ... [more ▼]

Rényi entropy was originally introduced in the field of information theory as a parametric relaxation of Shannon (in physics, Boltzmann–Gibbs) entropy. This has also fuelled different attempts to generalise statistical mechanics, although mostly skipping the physical arguments behind this entropy and instead tending to introduce it artificially. However, as we will show, modifications to the theory of statistical mechanics are needless to see how Rényi entropy automatically arises as the average rate of change of free energy over an ensemble at different temperatures. Moreover, this notion is extended by considering distributions for isospectral, non-isothermal processes, resulting in relative versions of free energy, in which the Kullback–Leibler divergence or the relative version of Rényi entropy appear within the structure of the corrections to free energy. These generalisa- tions of free energy recover the ordinary thermodynamic potential whenever isothermal processes are considered. [less ▲]

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See detailFrom predicting to learning dissipation from pair correlations of active liquids
Rassolov, Gregory; Tociu, Laura; Fodor, Etienne UL et al

in Journal of Chemical Physics (2022)

Active systems, which are driven out of equilibrium by local non-conservative forces, can adopt unique behaviors and configurations. An important challenge in the design of novel materials, which utilize ... [more ▼]

Active systems, which are driven out of equilibrium by local non-conservative forces, can adopt unique behaviors and configurations. An important challenge in the design of novel materials, which utilize such properties, is to precisely connect the static structure of active systems to the dissipation of energy induced by the local driving. Here, we use tools from liquid-state theories and machine learning to take on this challenge. We first analytically demonstrate for an isotropic active matter system that dissipation and pair correlations are closely related when driving forces behave like an active temperature. We then extend a nonequilibrium mean-field framework for predicting these pair correlations, which unlike most existing approaches is applicable even for strongly interacting particles and far from equilibrium, to predicting dissipation in these systems. Based on this theory, we reveal a robust analytic relation between dissipation and structure, which holds even as the system approaches a nonequilibrium phase transition. Finally, we construct a neural network that maps static configurations of particles to their dissipation rate without any prior knowledge of the underlying dynamics. Our results open novel perspectives on the interplay between dissipation and organization out of equilibrium. [less ▲]

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See detailCurrent cross correlations in a quantum Hall collider at filling factor two
Idrisov, Edvin UL; Levkivskyi, Ivan; Sukhorukov, Eugene et al

in Physical Review. B, Condensed Matter (2022)

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See detailProbabilistic Deep Learning for Real-Time Large Deformation Simulations
Deshpande, Saurabh UL; Lengiewicz, Jakub UL; Bordas, Stéphane UL

in Computer Methods in Applied Mechanics and Engineering (2022), 398(0045-7825), 115307

For many novel applications, such as patient-specific computer-aided surgery, conventional solution techniques of the underlying nonlinear problems are usually computationally too expensive and are ... [more ▼]

For many novel applications, such as patient-specific computer-aided surgery, conventional solution techniques of the underlying nonlinear problems are usually computationally too expensive and are lacking information about how certain can we be about their predictions. In the present work, we propose a highly efficient deep-learning surrogate framework that is able to accurately predict the response of bodies undergoing large deformations in real-time. The surrogate model has a convolutional neural network architecture, called U-Net, which is trained with force–displacement data obtained with the finite element method. We propose deterministic and probabilistic versions of the framework. The probabilistic framework utilizes the Variational Bayes Inference approach and is able to capture all the uncertainties present in the data as well as in the deep-learning model. Based on several benchmark examples, we show the predictive capabilities of the framework and discuss its possible limitations. [less ▲]

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See detailOutage Constrained Robust BeamformingOptimization for Multiuser IRS-AssistedAnti-Jamming Communications With Incomplete Information
Sun, Yifu; An, Kang; Luo, Junshan et al

in IEEE Internet of Things Journal (2022), 9(15), 13298-13314

Malicious jamming attacks have been regarded asa serious threat to Internet of Things (IoT) networks, which cansignificantly degrade the quality of service (QoS) of users. Thispaper utilizes an ... [more ▼]

Malicious jamming attacks have been regarded asa serious threat to Internet of Things (IoT) networks, which cansignificantly degrade the quality of service (QoS) of users. Thispaper utilizes an intelligent reflecting surface (IRS) to enhanceanti-jamming performance due to its capability in reconfiguringthe wireless propagation environment via dynamicly adjustingeach IRS reflecting elements. To enhance the communicationperformance against jamming attacks, a robust beamformingoptimization problem is formulated in a multiuser IRS-assistedanti-jamming communications scenario with or without imperfectjammer’s channel state information (CSI). In addition, we furtherconsider the fact that the jammer’s transmit beamforming cannot be known at BS. Specifically, with no knowledge of jammerstransmit beamforming, the total transmit power minimizationproblems are formulated subject to the outage probability re-quirements of legitimate users with the jammer’s statistical CSI,and signal-to-interference-plus-noise ratio (SINR) requirementsof legitimate users without the jammer’s CSI, respectively.By applying the Decomposition-based large deviation inequal-ity (DBLDI), Bernstein-type inequality (BTI), Cauchy-Schwarzinequality, and penalty non-smooth optimization method, weefficiently solve the initial intractable and non-convex problems.Numerical simulations demonstrate that the proposed anti-jamming approaches achieve superior anti-jamming performanceand lower power-consumption compared to the non-IRS schemeand reveal the impact of key parameters on the achievable systemperformance. [less ▲]

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See detailTesting market regulations in experimental asset markets –The case of margin purchases
Neugebauer, Tibor UL; Füllbrunn, Sascha

in Journal of Economic Behavior and Organization (2022), 200

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See detailRobust Congestion Control for Demand-Based Optimization in Precoded Multi-Beam High Throughput Satellite Communications
Bui, Van-Phuc; Chien, Trinh-Van; Lagunas, Eva UL et al

in IEEE Transactions on Communications (2022)

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See detailHistories of the past and histories of the future: Pandemics and historians of education
Grosvenor, Ian; Priem, Karin UL

in Paedagogica Historica (2022)

The COVID-19 outbreak at the beginning of the 2020s not only marked a dramatic moment in world health, but also the start of manifold and entangled global crises that seem to define a watershed moment ... [more ▼]

The COVID-19 outbreak at the beginning of the 2020s not only marked a dramatic moment in world health, but also the start of manifold and entangled global crises that seem to define a watershed moment with severe effects on education. Pandemics we know are recurrent events. Faced with COVID-19 some historians have looked to previous pandemics to understand the nature of the disease and its trajectory, and how previous generations have dealt with similar health crises. This special issue intends not to reinforce narratives of the past but rather to question them. The histories that have been written for this special issue Histories of the Past and Histories of the Future: Pandemics and Historians of Education offer insights that refer to past and future research agendas. They look at the mediation and circulation of knowledge during past pandemics, trace unheard voices and emotions of pandemics, analyse national policies and emerging discourses, and underline the entangled histories of education and pandemics. Collectively the articles brought together in this issue forcibly suggest that the most fruitful and rewarding way forward to studying past pandemics lies in thinking ecologically. By asses- sing the myriad consequences of living in ” pandemic times,” of confronting exposure, transmission, transmutation, disruption, and loss, and looking to community and collective futures we believe we cannot study pandemics and their impact on education and children's lives without widening the aperture of our research. Adopting an ecological approach will help us to not only actively engage with histories of the present and contemporary collecting, but also offer the possibility of new understandings and new insights into the dynamics and consequences of past pandemics. [less ▲]

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See detailLos pagos por servicios ambientales en la Ciudad de México: un enfoque de coherencia de políticas públicas
Cetina Arenas, Lucero; Koff, Harlan UL; Maganda, Carmen et al

in Región y Sociedad (2022), 34

Objective: to analyze two programs of environmental services payment in the Mexico City Soil Conservation Lands using the policy coherence for development theoretical-methodological framework. Methodology ... [more ▼]

Objective: to analyze two programs of environmental services payment in the Mexico City Soil Conservation Lands using the policy coherence for development theoretical-methodological framework. Methodology: qualitative analysis based on policy coherence typologies. Results: the programs’ beneficiaries economically depend on the associated subsidies; there are restrictions for the economic activities’ development; the financial mechanisms are inefficient and there is a lack of a sustainability vision that considers the socioeconomic dimensions. Limitations: participation of authorities and community members in this type of study is limited and there is a lack of information on the relationships between institutions and work programs. Value: the analysis of peri-urban public policies through the policy coherence for development framework. Conclusions: applying the policy coherence for development framework helped identifying imbalances and synergies among the policy dimensions analyzed. This methodology can promote the mainstreaming of sustainability norms. [less ▲]

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See detailFinancial development and income inequality: A meta-analysis
Chletsos, Michael; Sintos, Andreas UL

in Journal of Economic Surveys (2022)

The voluminous empirical research on the effect of financial development on income inequality has yielded mixed results. In this paper, we collect 2127 estimates reported in 116 published studies that ... [more ▼]

The voluminous empirical research on the effect of financial development on income inequality has yielded mixed results. In this paper, we collect 2127 estimates reported in 116 published studies that investigate the effect of financial development on income inequality. Although our initial tests for publication bias (which do not account for moderator variables) show that the current literature does not suffer from publication selectivity, once we control for a set of moderator variables, we find evidence of mild publication bias in favor of positive estimates (i.e., the current literature favors the publication of studies that find that financial development increases income inequality). In addition, our results suggest that the overall effect of financial development on income inequality is on average zero, but that its sign and magnitude depend systematically on various study characteristics. The characteristics of data and estimation methods, whether endogeneity is taken into account, the different measures of financial development and the inclusion of financial openness, inflation and income variables in the regressions matter significantly for the effect of financial development on inequality. [less ▲]

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See detailAnother end of the world is possible : Nicholas Georgescu-Roegen, from bioeconomy to architecture
Reyes Nájera, César UL; Popova, Simona Bozhidarova UL

in ARQ (2022), (111), 52-59

Can technology ignore the physical limits of growth, or can it only provide us with more and better products, but also with more and better waste? This is a text that reflects on the entropic nature of ... [more ▼]

Can technology ignore the physical limits of growth, or can it only provide us with more and better products, but also with more and better waste? This is a text that reflects on the entropic nature of construction materials and their economic process, based on the work of the Romanian economist Nicholas Georgescu-Roegen. The discussion helps us to critically reflect if architecture can, given its material quality, extend the life or death of the world, or whether it is simply an activity that contributes for us to having "a short but extravagant existence". [less ▲]

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See detailLe droit à la sauce piquante n°27 - Aout 2022
Hiez, David UL; Laurent, Rémi

in Le droit à la sauce piquante (2022), 27

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See detailInformalität im regionalen Wachstumsprozess. Einblick in eine „Black Box“ der Planungspraxis am Beispiel Luxemburgs
Schmitz, Nicolas; Hesse, Markus UL; Becker, Tom UL

in Raumforschung und Raumordnung (2022)

Der Beitrag behandelt die Steuerung des Siedlungsflächenwachstums im Großherzogtum Luxemburg aus der Perspektive von Informalität. Luxemburg steht unter einem hohen demographischen und ökonomischen ... [more ▼]

Der Beitrag behandelt die Steuerung des Siedlungsflächenwachstums im Großherzogtum Luxemburg aus der Perspektive von Informalität. Luxemburg steht unter einem hohen demographischen und ökonomischen Wachstumsdruck in allen Landesteilen (Hauptstadt, altindustrialisierter Süden, ländlicher Norden), der das Planungssystem stark herausfordert. Zugleich gibt es keine formelle Regionalplanung, allenfalls Ansätze interkommunaler Kooperation, die überwiegend freiwilliger Natur sind. Anhand von empirischen Fallstudien in zwei wachstumsstarken Gemeinden (Junglinster, Schuttrange) skizziert der Beitrag Planungsentscheidungen im institutionellen Dreieck zwischen Kommune, Staat und privaten Trägern. Informalität dient hier nicht nur zur Kompensation fehlender planerischer Steuerung, sondern auch dem Umgang mit der komplexen Rechtsmaterie des Landes. Informell kommen auch die vitalen Interessen der Grundeigentümer ins Spiel: Da ein Teil der Wohlfahrtseffekte des Landes über Grund und Boden realisiert wird, sind Spekulationsinteressen immanent, haben ein hohes Blockadepotenzial. In diesem Kontext formuliert der Beitrag erste Überlegungen für ein regionales Wachstumsmanagement, das die Lücke zwischen staatlicher Landesplanung und kommunalem Eigensinn schließen könnte. [less ▲]

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See detailSSPCATCHER: Learning to catch security patches
Sawadogo, Delwende Arthur; Bissyande, Tegawendé François D Assise UL; Moha, Naouel et al

in Empirical Software Engineering (2022), 27

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See detailInvestigations on the lateral-torsional buckling of an innovative U-shaped steel beam in construction stage of composite beam
Turetta, Maxime; Odenbreit, Christoph UL; Khelil, Abdelouahab et al

in Structures (2022), 44

Structural elements of building have to meet a multitude of requirements. Besides the static load bearing capacity, common requirements are the structural integrity and efficiency during the construction ... [more ▼]

Structural elements of building have to meet a multitude of requirements. Besides the static load bearing capacity, common requirements are the structural integrity and efficiency during the construction stage and sufficient fire resistance. Within the French CIFRE research project COMINO, an innovative type of composite beam was developed for buildings beams with a span of 6 -12m, which need fire resistance until 2 hours with no additional supports at construction stage. The developed solution is composed of a steel U-section acting as a formwork in construction stage for a reinforced concrete part that provides the fire resistance. In the exploitation stage, the steel and the reinforced concrete are acting together as a composite beam. In construction stage, when the concrete is not hardened and thus the stabilizing effect is not present, the steel beam, is subjected to Lateral-Torsional Buckling. In order to investigate the structural behaviour of the new developed steel section in construction stage, a single full-scale test has been carried out at the Laboratory of Structural Engineering of the University of Luxembourg. This article focuses on the stability of the steel beam made of thin-walled steel parts without considering any stabilizing effect. The test results are then compared to the results of numerical investigations and to the analytical solutions of EN 1993. [less ▲]

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See detailBackscatter Sensors Communication for 6G Low-Powered NOMA-Enabled IoT Networks Under Imperfect SIC
Ahmed, Manzoor; Khan, Wali Ullah UL; Ihsan, Asim et al

in IEEE Systems Journal (2022)

The combination of nonorthogonal multiple access (NOMA) using power-domain with backscatter communication (BC) is expected to connect large-scale Internet of things (IoT) devices in the future sixth ... [more ▼]

The combination of nonorthogonal multiple access (NOMA) using power-domain with backscatter communication (BC) is expected to connect large-scale Internet of things (IoT) devices in the future sixth-generation era. This article introduces a BC in a multicell IoT network, where a source in each cell transmits a superimposed signal to its associated IoT devices using NOMA. The backscatter sensor tag (BST) also transmits data to IoT devices by reflecting and modulating the superimposed signal of the source. A new optimization framework is provided that simultaneously optimizes the total power of each source, power allocation coefficient of IoT devices, and RC of BST under imperfect successive interference cancellation decoding. This work aims to maximize the total energy efficiency (EE) of the IoT network subject to the quality of services of each IoT device. The problem is first transformed using the Dinkelbach method and then decoupled into two subproblems. The Karush–Kuhn–Tucker conditions and dual Lagrangian method are employed to obtain efficient solutions. In addition, we also calculate the EE of the conventional NOMA network without BC as a benchmark framework. Simulation results unveil the advantage of our considered NOMA BC network over the conventional NOMA network in terms of system total EE. [less ▲]

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See detailMassive MIMO Hybrid Precoding for LEO Satellite Communications With Twin-Resolution Phase Shifters and Nonlinear Power Amplifiers
You, Li; Qiang, Xiaoyu; Li, Ke-Xin et al

in IEEE Transactions on Communications (2022), 70(8), 5543-5557

The massive multiple-input multiple-output (MIMO) transmission technology has recently attracted much attention in the non-geostationary, e.g., low earth orbit (LEO) satellite communication (SATCOM ... [more ▼]

The massive multiple-input multiple-output (MIMO) transmission technology has recently attracted much attention in the non-geostationary, e.g., low earth orbit (LEO) satellite communication (SATCOM) systems since it can significantly improve the energy efficiency (EE) and spectral efficiency. In this work, we develop a hybrid analog/digital precoding technique in the massive MIMO LEO SATCOM downlink, which reduces the onboard hardware complexity and power consumption. In the proposed scheme, the analog precoder is implemented via a more practical twin-resolution phase shifting (TRPS) network to make a meticulous tradeoff between the power consumption and array gain. In addition, we consider and study the impact of the distortion effect of the nonlinear power amplifiers (NPAs) in the system design. By jointly considering all the above factors, we propose an efficient algorithmic approach for the TRPS-based hybrid precoding problem with NPAs. Numerical results show the EE gains considering the nonlinear distortion and the performance superiority of the proposed TRPS-based hybrid precoding scheme over the baselines. [less ▲]

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See detailConnected Vehicle Platforms for Dynamic Insurance
Colot, Christian UL; Robinet, François UL; Nichil, Geoffrey et al

in in Proceedings of the 6th International Conference on Intelligent Traffic and Transportation (2022)

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See detailFederated Learning Meets Contract Theory: Economic-Efficiency Framework for Electric Vehicle Networks
Saputra, Yuris M.; Nguyen, Diep N.; Dinh, Thai Hoang et al

in IEEE Transactions on Mobile Computing (2022), 21(8), 2803-2817

In this paper, we propose a novel energy-efficient framework for an electric vehicle (EV) network using a contract theoretic-based economic model to maximize the profits of charging stations (CSs) and ... [more ▼]

In this paper, we propose a novel energy-efficient framework for an electric vehicle (EV) network using a contract theoretic-based economic model to maximize the profits of charging stations (CSs) and improve the social welfare of the network. Specifically, we first introduce CS-based and CS clustering-based decentralized federated energy learning (DFEL) approaches which enable the CSs to train their own energy transactions locally to predict energy demands. In this way, each CS can exchange its learned model with other CSs to improve prediction accuracy without revealing actual datasets and reduce communication overhead among the CSs. Based on the energy demand prediction, we then design a multi-principal one-agent (MPOA) contract-based method. In particular, we formulate the CSs' utility maximization as a non-collaborative energy contract problem in which each CS maximizes its utility under common constraints from the smart grid provider (SGP) and other CSs' contracts. Then, we prove the existence of an equilibrium contract solution for all the CSs and develop an iterative algorithm at the SGP to find the equilibrium. Through simulation results using the dataset of CSs' transactions in Dundee city, the United Kingdom between 2017 and 2018, we demonstrate that our proposed method can achieve the energy demand prediction accuracy improvement up to 24.63% and lessen communication overhead by 96.3% compared with other machine learning algorithms. Furthermore, our proposed method can outperform non-contract-based economic models by 35% and 36% in terms of the CSs' utilities and social welfare of the network, respectively. [less ▲]

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See detailZones and zoning: Linking the geographies of freeports with ArtTech and financial market making
Dörry, Sabine UL; Hesse, Markus UL

in Geoforum (2022)

Freeports and special economic zones (SEZs) are established policy tools to attract foreign investment at specific locations, based on the de-coupling of sovereignty and territory. As a result, they ... [more ▼]

Freeports and special economic zones (SEZs) are established policy tools to attract foreign investment at specific locations, based on the de-coupling of sovereignty and territory. As a result, they emerged not only in developmental contexts, but also in tax havens and financial centres. Recently, freeports and SEZs have shifted from responding to global competition for spaces best suited to attract tangible manufacturing to responding to competition for spaces with best conditions to enable value extraction and wealth shielding. We develop the argument on the emerging industry of ArtTech and new ‘fine art freeports’ that thrive on two core social practices: fracturing property rights to enhance financial liquidity and trading activity in highly exclusive fine-art markets, and offshoring – or zoning – to exploit freeport-facilitated relations for market making and rent-seeking.Besides such practices to make and game markets, freeports supply important physical infrastructure for fine-art technical and custody services that precondition any form of value creation. As such, freeports are important spaces for policy experimentation. Contrary to the conventional belief about free zones in general and freeports in particular, however, their economic impact remains limited. We explain this by conceptualising freeports as ‘zones’ defined or designed by specific processes of ‘zoning’ that link their multiple geographies. We conclude that freeports are no sites of exception but spaces that help legitimise novel institutional and economic arrangements emergent in the economy at large. [less ▲]

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See detailThe effects of IMF conditional programs on the unemployment rate
Chletsos, Michael; Sintos, Andreas UL

in European Journal of Political Economy (2022)

The fundamental mission of the International Monetary Fund (IMF) is to ensure global financial stability and to assist countries in economic turmoil. Although there is a consensus that IMF-supported ... [more ▼]

The fundamental mission of the International Monetary Fund (IMF) is to ensure global financial stability and to assist countries in economic turmoil. Although there is a consensus that IMF-supported programs can have a direct effect on the labor market of recipient countries, it remains unclear how IMF participation decision and conditionalities attached to IMF loans can affect the unemployment rate of borrowing countries. Using a world sample of countries from 1980 to 2014, we investigate how lending conditional programs of the IMF affect the unemployment rate. Our analyses account for the selection bias related to, first, the IMF participation decision and, second, the conditions included within the program. We show that IMF program participation significantly increases the unemployment rate of recipient countries. Once we control for the number of conditions, however, we find that only IMF conditions have a detrimental and highly significant effect on the unemployment rate. There is evidence that the adverse short-run effect of IMF conditions holds robust in the long-run. Disaggregating IMF conditionality by issue area, we find adverse effects on the unemployment rate for four policy areas: labor market deregulation, reforms requiring privatization of state-owned enterprises, external sector reforms stipulating trade and capital account liberalization, and fiscal policy reforms that restrain government expenditure. Our initial results are found to be robust across alternative empirical specifications. [less ▲]

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See detailRate Splitting Multiple Access for Next Generation Cognitive Radio Enabled LEO Satellite Networks
Khan, Wali Ullah UL; Ali, Zain; Lagunas, Eva UL et al

in Bulletin. Cornell University Libraries (2022)

Low Earth Orbit (LEO) satellite communication (SatCom) has drawn particular attention recently due to its high data rate services and low round-trip latency. It has low launching and manufacturing costs ... [more ▼]

Low Earth Orbit (LEO) satellite communication (SatCom) has drawn particular attention recently due to its high data rate services and low round-trip latency. It has low launching and manufacturing costs than Medium Earth Orbit (MEO) and Geostationary Earth Orbit (GEO) satellites. Moreover, LEO SatCom has the potential to provide global coverage with a high-speed data rate and low transmission latency. However, the spectrum scarcity might be one of the challenges in the growth of LEO satellites, impacting severe restrictions on developing ground-space integrated networks. To address this issue, cognitive radio and rate splitting multiple access (RSMA) are the two emerging technologies for high spectral efficiency and massive connectivity. This paper proposes a cognitive radio enabled LEO SatCom using RSMA radio access technique with the coexistence of GEO SatCom network. In particular, this work aims to maximize the sum rate of LEO SatCom by simultaneously optimizing the power budget over different beams, RSMA power allocation for users over each beam, and subcarrier user assignment while restricting the interference temperature to GEO SatCom. The problem of sum rate maximization is formulated as non-convex, where the global optimal solution is challenging to obtain. Thus, an efficient solution can be obtained in three steps: first we employ a successive convex approximation technique to reduce the complexity and make the problem more tractable. Second, for any given resource block user assignment, we adopt Karush–Kuhn–Tucker (KKT) conditions to calculate the transmit power over different beams and RSMA power allocation of users over each beam. Third, using the allocated power, we design an efficient algorithm based on the greedy approach for resource block user assignment. For comparison, we propose two suboptimal schemes with fixed power allocation over different beams and random resource block user assignment as the benchmark. Numerical results provided in this work are obtained based on the Monte Carlo simulations, which demonstrate the benefits of the proposed optimization scheme compared to the benchmark schemes. [less ▲]

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See detailCemeteries and crematoria, forgotten public space in multicultural Europe. An agenda for inclusion and citizenship
Maddrell, Avril; Beebeejaun, Yasminah; Wingren, Carola et al

in Area (2022)

In western Europe, municipal or otherwise state-commissioned cemeteries and crematoria are public spaces and services, open to all. Cemeteries and crematoria grounds are neglected in geographical ... [more ▼]

In western Europe, municipal or otherwise state-commissioned cemeteries and crematoria are public spaces and services, open to all. Cemeteries and crematoria grounds are neglected in geographical, planning and policy debates about the character, design, management, use and accessibility of public spaces, and likewise debates about the social inclusion of migrants and minorities. This may reflect a tendency to situate cemeteries socially and geographically in the peripheries of contemporary European society, but they are, nonetheless, sites of vital public health infrastructure, as well as being highly significant symbolic, religious-spiritual, secular-sacred, and emotionally-laden places. Examining cemeteries-crematoria against a criteria of inclusive public space provides new insights into i) the nature of public space and its governance; ii) rights and barriers to shared public spaces and associated infrastructure in everyday multicultural contexts; iii) national-local negotiations of majority-minorities social relations and cultural practices in and through public spaces; and iv) the need to place municipal cemeteries-crematoria centre stage in scholarship and policy on public space which is culturally inclusive and serves all citizens. [less ▲]

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See detailEnergy Efficient Transmission Design for NOMA Backscatter-Aided UAV Networks with Imperfect CSI
AlJubayrin, Saad; Al-Wesabi, Fahd N.; Alsolai, Hadeel et al

in Drones (2022)

The recent combination of ambient backscatter communication (ABC) with non-orthogonal multiple access (NOMA) has shown great potential for connecting large-scale Internet of Things (IoT) in future ... [more ▼]

The recent combination of ambient backscatter communication (ABC) with non-orthogonal multiple access (NOMA) has shown great potential for connecting large-scale Internet of Things (IoT) in future unmanned aerial vehicle (UAV) networks. The basic idea of ABC is to provide battery-free transmission by harvesting the energy of existing RF signals of WiFi, TV towers, and cellular base stations/UAV. ABC uses smart sensor tags to modulate and reflect data among wireless devices. On the other side, NOMA makes possible the communication of more than one IoT on the same frequency. In this work, we provide an energy efficient transmission design ABC-aided UAV network using NOMA. This work aims to optimize the power consumption of a UAV system while ensuring the minimum data rate of IoT. Specifically, the transmit power of UAVs and the reflection coefficient of the ABC system are simultaneously optimized under the assumption of imperfect channel state information (CSI). Due to co-channel interference among UAVs, imperfect CSI, and NOMA interference, the joint optimization problem is formulated as non-convex, which involves high complexity and makes it hard to obtain the optimal solution. Thus, it is first transformed and then solved by a sub-gradient method with low complexity. In addition, a conventional NOMA UAV framework is also studied for comparison without involving ABC. Numerical results demonstrate the benefits of using ABC in a NOMA UAV network compared to the conventional UAV framework. [less ▲]

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See detailInbound Carrier Plan Optimization for Adaptive VSAT Networks
Lacoste, Clément UL; Alves Martins, Wallace UL; Chatzinotas, Symeon UL et al

in IEEE Transactions on Aerospace and Electronic Systems (2022)

The past decades witnessed the application of adaptive modulation and coding (ACM) in satellite links. However, ACM technologies come at the cost of higher complexity when designing the network’s carrier ... [more ▼]

The past decades witnessed the application of adaptive modulation and coding (ACM) in satellite links. However, ACM technologies come at the cost of higher complexity when designing the network’s carrier plan and user terminals. Accounting for those issues is even more important when the satellite link uses frequencies in Ka band and above, where the attenuation caused by tropospheric phenomena is a major concern. In this paper, we propose a solution for the inbound, i.e. return link, carrier plan sizing of very small aperture terminal (VSAT) networks. As tropospheric attenuation is a key factor, we present a mathematical problem formulation based on spatially correlated attenuation time series generators. Our proposed sizing scheme is formulated as a mixed integer linear programming (MILP) optimization problem. The numerical results for a test scenario in Europe show a 10 to 50% bandwidth improvement over traditional sizing methods for outage probabilities lower than 1%. [less ▲]

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See detailL-invariants of Artin motives
Dimitrov, Mladen; Maksoud, Alexandre UL

in Annales mathématiques du Québec (2022)

We compute Benois L-invariants of weight 1 cuspforms and of their adjoint representations and show how this extends Gross’ p-adic regulator to Artin motives which are not critical in the sense of Deligne ... [more ▼]

We compute Benois L-invariants of weight 1 cuspforms and of their adjoint representations and show how this extends Gross’ p-adic regulator to Artin motives which are not critical in the sense of Deligne. Benois’ construction depends on the choice of a regular submodule which is well understood when the representation is p-regular, as it then amounts to the choice of a “motivic” p-refinement. The situation is dramatically different in the p-irregular case, where the regular submodules are parametrized by a flag variety and thus depend on continuous parameters. We are nevertheless able to show in some examples, how Hida theory and the geometry of the eigencurve can be used to detect a finite number of choices of arithmetic and “mixed-motivic” significance. [less ▲]

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See detailExploiting constructive interference in symbol level hybrid beamforming for dual-function radar-communication system
Wang, Bowen; Wu, Linlong UL; Cheng, Ziyang et al

in IEEE Wireless Communications Letters (2022), 11(10), 2071--2075

In this letter, we study the Hybrid Beamforming (HBF) design for a Dual-Function Radar-Communication (DFRC) system, which serves Multiple Users (MUs) and detects a target in the presence of signal ... [more ▼]

In this letter, we study the Hybrid Beamforming (HBF) design for a Dual-Function Radar-Communication (DFRC) system, which serves Multiple Users (MUs) and detects a target in the presence of signal-dependent clutters, simultaneously. Unlike conventional beamforming strategies, we propose a novel one on the symbol level, which exploits Constructive Interference (CI) to achieve a trade-off between radar and communication using one platform. To implement this novel strategy, we jointly design the DFRC transmit HBF and radar receive beamforming by maximizing the radar Signal to Interference plus Noise Ratio (SINR) while ensuring the Quality of Service (QoS) of downlink communication. To tackle the formulated non-convex problem, we propose an iterative algorithm, which combines the Majorization-Minimization (MM) and Alternating Direction Method of Multipliers (ADMM) judiciously. The numerical experiments indicate that our algorithm yields the CI properly for robust communications and achieves better performance than the conventional HBF benchmarks in both communication bit error rate and radar SINR. [less ▲]

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See detailGaussian approximation for sums of region-stabilizing scores
Bhattacharjee, Chinmoy UL; Molchanov, Ilya

in Electronic Journal of Probability (2022), 27

We consider the Gaussian approximation for functionals of a Poisson process that are expressible as sums of region-stabilizing (determined by the points of the process within some specified regions) score ... [more ▼]

We consider the Gaussian approximation for functionals of a Poisson process that are expressible as sums of region-stabilizing (determined by the points of the process within some specified regions) score functions and provide a bound on the rate of convergence in the Wasserstein and the Kolmogorov distances. While such results have previously been shown in Lachièze-Rey, Schulte and Yukich (2019), we extend the applicability by relaxing some conditions assumed there and provide further insight into the results. This is achieved by working with stabilization regions that may differ from balls of random radii commonly used in the literature concerning stabilizing functionals. We also allow for non-diffuse intensity measures and unbounded scores, which are useful in some applications. As our main application, we consider the Gaussian approximation of number of minimal points in a homogeneous Poisson process in $[0,1]^d$ with $d \geq 2$, and provide a presumably optimal rate of convergence. [less ▲]

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See detailPCfun: a hybrid computational framework for systematic characterization of protein complex function
Sharma, Varun; Fossati, Andrea; Ciuffa, Rodolfo et al

in Briefings in Bioinformatics (2022), 23(4), 239

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See detailThe Failure of “Yugoslavia’s Last Chance”: Ante Marković and his Reformists in the 1990 Elections
Glaurdic, Josip UL; Filipovic, Vladimir; Lesschaeve, Christophe UL

in Nationalities Papers (2022)

The last Prime Minister of Yugoslavia Ante Marković was considered by many within the country and in the international community to be Yugoslavia’s last chance for a peaceful transition toward democracy ... [more ▼]

The last Prime Minister of Yugoslavia Ante Marković was considered by many within the country and in the international community to be Yugoslavia’s last chance for a peaceful transition toward democracy and capitalism. In spite of his popularity, the Reformist party he created failed decisively in the first democratic elections of 1990. We expose the reasons for this failure by analyzing electoral, economic, and sociodemographic data on the level of more than two hundred Yugoslav municipalities where the Reformists put forward their candidates. Our analysis shows that the party’s failure had little to do with the voters’ exposure to the effects of the free market reforms undertaken by Marković’s federal government during this period. Instead, the Reformists’ results were largely determined by the communities’ ethnic makeup and interethnic balance. The Reformists suffered at the hands of a strong negative campaign by the Serbian regime of Slobodan Milošević, and they were squeezed out by the ethnically based parties that benefited from voters behaving strategically in the electoral marketplace dominated by questions of nationalism. The analysis presented here offers important lessons for our understanding of Yugoslavia’s breakup, post-communist transitions in general, and electoral politics in societies on the verge of ethnic conflict. [less ▲]

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See detailA Hybrid Modelling Approach For Aerial Manipulators
Kremer, Paul UL; Sanchez Lopez, Jose Luis UL; Voos, Holger UL

in Journal of Intelligent and Robotic Systems (2022)

Aerial manipulators (AM) exhibit particularly challenging, non-linear dynamics; the UAV and its manipulator form a tightly coupled dynamic system, mutually impacting each other. The mathematical model ... [more ▼]

Aerial manipulators (AM) exhibit particularly challenging, non-linear dynamics; the UAV and its manipulator form a tightly coupled dynamic system, mutually impacting each other. The mathematical model describing these dynamics forms the core of many solutions in non-linear control and deep reinforcement learning. Traditionally, the formulation of the dynamics involves Euler angle parametrization in the Lagrangian framework or quaternion parametrization in the Newton-Euler framework. The former has the disadvantage of giving birth to singularities and the latter being algorithmically complex. This work presents a hybrid solution, combining the benefits of both, namely a quaternion approach leveraging the Lagrangian framework, connecting the singularity-free parameterization with the algorithmic simplicity of the Lagrangian approach. We do so by offering detailed insights into the kinematic modeling process and the formulation of the dynamics of a general aerial manipulator. The obtained dynamics model is validated experimentally against a real-time physics engine. A practical application of the obtained dynamics model is shown in the context of a computed torque feedback controller (feedback linearization), where we analyze its real-time capability with increasingly complex AM models. [less ▲]

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See detailOne step ahead: mapping the Italian and German cybersecurity laws against the proposal for a NIS2 directive
Schmitz, Sandra UL; Chiara, Pier Giorgio UL

in International Cybersecurity Law Review (2022)

With the COVID-19 pandemic accelerating digital transformation of the Single Market, the European Commission also speeded up the review of the first piece of European Union (EU)-wide cybersecurity ... [more ▼]

With the COVID-19 pandemic accelerating digital transformation of the Single Market, the European Commission also speeded up the review of the first piece of European Union (EU)-wide cybersecurity legislation, the NIS Directive. Originally foreseen for May 2021, the Commission presented the review as early as December 2020 together with a Proposal for a NIS2 Directive. Almost in parallel, some Member States strengthened (or adopted) national laws beyond the scope of the NIS Directive to respond adequately to the fast-paced digital threat landscape. Against this backdrop, the article investigates the national interventions in the field of cybersecurity recently adopted by Italy and Germany. In order to identify similarities and divergences of the Italian and German national frameworks with the European Commission’s Proposal for a NIS2 Directive, the analysis will focus on selected aspects extrapolated from the Commission Proposal, namely: i) the enlarged scope; ii) detailed cybersecurity risk-management measures; iii) more stringent supervisory measures; and, iv) stricter enforcement requirements, including harmonised sanctions across the EU. The article concludes that the national cybersecurity legal frameworks under scrutiny already match the core of the proposed changes envisaged by the NIS2 Proposal. [less ▲]

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See detailBoosting Quantum Battery-Based IoT Gadgets via RF-Enabled Energy Harvesting
Gautam, Sumit; Solanki, Sourabh UL; Sharma, Shree Krishna et al

in Sensors (2022), 22(14), 1-19

The search for a highly portable and efficient supply of energy to run small-scale wireless gadgets has captivated the human race for the past few years. As a part of this quest, the idea of realizing a ... [more ▼]

The search for a highly portable and efficient supply of energy to run small-scale wireless gadgets has captivated the human race for the past few years. As a part of this quest, the idea of realizing a Quantum battery (QB) seems promising. Like any other practically tractable system, the design of QBs also involve several critical challenges. The main problem in this context is to ensure a lossless environment pertaining to the closed-system design of the QB, which is extremely difficult to realize in practice. Herein, we model and optimize various aspects of a Radio-Frequency (RF) Energy Harvesting (EH)-assisted, QB-enabled Internet-of-Things (IoT) system. Several RF-EH modules (in the form of micro- or nano-meter-sized integrated circuits (ICs)) are placed in parallel at the IoT receiver device, and the overall correspondingly harvested energy helps the involved Quantum sources achieve the so-called quasi-stable state. Concretely, the Quantum sources absorb the energy of photons that are emitted by a photon-emitting device controlled by a micro-controller, which also manages the overall harvested energy from the RF-EH ICs. To investigate the considered framework, we first minimize the total transmit power under the constraints on overall harvested energy and the number of RF-EH ICs at the QB-enabled wireless IoT device. Next, we optimize the number of RF-EH ICs, subject to the constraints on total transmit power and overall harvested energy. Correspondingly, we obtain suitable analytical solutions to the above-mentioned problems, respectively, and also cross-validate them using a non-linear program solver. The effectiveness of the proposed technique is reported in the form of numerical results, which are both theoretical and simulations based, by taking a range of operating system parameters into account. [less ▲]

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See detailA Gaussian damage function combined with sliced finite-element meshing for damage detection
Schommer, Sebastian; Dakhili, Khatereh UL; Nguyen, Viet Ha et al

in Journal of Civil Structural Health Monitoring (2022)

Bridges are among the most important components of transportation systems. Timely damage detection of these structures not only ensures reliability but also prevents catastrophic failures. This paper ... [more ▼]

Bridges are among the most important components of transportation systems. Timely damage detection of these structures not only ensures reliability but also prevents catastrophic failures. This paper addresses the damage assessment of bridges based on model updating techniques. Artificial damage was introduced to a beam that was a part of a real prestressed concrete bridge. The magnitude of the damage was increased stepwise, and static loading experiments were conducted in each step. A linear Finite-Element (FE) model with solid elements that were clustered into slices was utilised. A Gaussian bell-shaped curve was used as a damage function to describe the crack location using only three parameters. The experiments focused on sagging under dead load. Damage identification was performed in two steps using a coarse and a refined model. Initially, the FE model with a coarse mesh was updated to approximately localise the damage. Then, the FE model is refined in the vicinity of the approximately localised damage, and damage identification was accurately achieved. The results show that after the second step, the maximum error value of damage localisation is less than 0.5%. This approach could be later used to detect small damages that are not visible. [less ▲]

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See detailThe relationship between COVID-19 countermeasures at the workplace and psychological well-being. Findings from a nationally representative sample of Luxembourgish employees
Sischka, Philipp UL; Schmidt, Alexander F.; Steffgen, Georges UL

in Current Psychology (2022)

The COVID-19 pandemic has massively changed people’s working lives all over the world. While various studies investigated the effects from pandemic-induced unemployment and telecommuting, there is a lack ... [more ▼]

The COVID-19 pandemic has massively changed people’s working lives all over the world. While various studies investigated the effects from pandemic-induced unemployment and telecommuting, there is a lack of research regarding the impact of workplace COVID-19 countermeasures on well-being and mental health for employees who are still working on site. Thus, the aim of the present study was to investigate the prevalence of workplace COVID-19 countermeasures in organizations in Luxembourg. A person-centered approach was applied in order to explore how employees’ psychological well-being and health (i.e., general psychological well-being, vigor, work satisfaction, work-related burnout, somatic complaints, fear of COVID-19 infection) are impacted by organizational countermeasures and whether there are certain employee groups that are less protected by these. Results of a latent class analysis revealed four different classes (Low level of countermeasures, Medium level of countermeasures, High level of countermeasures, High level of countermeasures low distance). Employees working in a healthcare setting were more likely than employees working in a non-healthcare setting to be members of the High level of countermeasures low distance class. Class membership was meaningfully associated with all well-being outcomes. Members of the High level of countermeasures class showed the highest level of well-being, whereas Members of the Low level of countermeasures class and the High level of countermeasures low distance class showed the lowest level of well-being. Policy makers and organizations are recommended to increase the level of COVID-19 countermeasures as an adjunctive strategy to prevent and mitigate adverse mental health and well-being outcomes during the COVID-19 pandemic. [less ▲]

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See detailStudying the Parkinson's disease metabolome and exposome in biological samples through different analytical and cheminformatics approaches: a pilot study
Talavera Andujar, Begona UL; Aurich, Dagny UL; Aho, Velma UL et al

in Analytical and Bioanalytical Chemistry (2022)

Parkinson’s disease (PD) is the second most prevalent neurodegenerative disease, with an increasing incidence in recent years due to the ageing population. Genetic mutations alone only explain <10% of PD ... [more ▼]

Parkinson’s disease (PD) is the second most prevalent neurodegenerative disease, with an increasing incidence in recent years due to the ageing population. Genetic mutations alone only explain <10% of PD cases, while environmental factors, including small molecules, may play a significant role in PD. In the present work, 22 plasma (11 PD, 11 control) and 19 feces samples (10 PD, 9 control) were analyzed by non-target high resolution mass spectrometry (NT-HRMS) coupled to two liquid chromatography (LC) methods (reversed phase (RP) and hydrophilic interaction liquid chromatography (HILIC)). A cheminformatics workflow was optimized using open software (MS-DIAL and patRoon) and open databases (all public MSP-formatted spectral libraries for MS-DIAL, PubChemLite for Exposomics and the LITMINEDNEURO list for patRoon). Furthermore, five disease-specific databases and three suspect lists (on PD and related disorders) were developed, using PubChem functionality to identifying relevant unknown chemicals. The results showed that non-target screening with the larger databases generally provided better results compared with smaller suspect lists. However, two suspect screening approaches with patRoon were also good options to study specific chemicals in PD. The combination of chromatographic methods (RP and HILIC) as well as two ionization modes (positive and negative) enhanced the coverage of chemicals in the biological samples. While most metabolomics studies in PD have focused on blood and cerebrospinal fluid, we found a higher number of relevant features in feces, such as alanine betaine or nicotinamide, which can be directly metabolized by gut microbiota. This highlights the potential role of gut dysbiosis in PD development. [less ▲]

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See detailDetermination of Slip Factor between CNC-Cut Serrated Surfaces of S355J2 Grade Steel Plates
Yolacan, Firat; Schäfer, Markus UL

in Buildings (2022), 12(995),

Determination of Slip Factor between CNC-Cut Serrated Surfaces of S355J2 Grade Steel Plates by Taygun Fırat Yolaçan and Markus SchäferStructural joint configurations realized with serrated steel surfaces ... [more ▼]

Determination of Slip Factor between CNC-Cut Serrated Surfaces of S355J2 Grade Steel Plates by Taygun Fırat Yolaçan and Markus SchäferStructural joint configurations realized with serrated steel surfaces have started to be used in the construction fields to assemble the primary and the secondary structural members of civil engineering structures. The main advantages of these joint configurations rely on their flexibility to accommodate construction tolerances and their slip-resistant load-bearing mechanism against dynamic loading conditions. Therefore, it is important to reliably establish the characteristic value of the friction coefficient or in other words the slip factor between the serrated steel surfaces to design reliable slip-resistant connections. In this study, the characteristic slip factor between the CNC-cut serrated surfaces prepared from S355J2 grade steel plates is determined to investigate the impact of the CNC-cutting procedure on the slip-resistant load-bearing behaviour of steel-to-steel interfaces. Five experimental tests were performed according to EN1090-2, Annex G. The results are presented as the load-slip curves, variation of the bolt pre-tension load level, nominal and actual slip factors for the tested configuration of the CNC-cut serrated steel-to-steel interface [less ▲]

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See detailSLNR-based Secure Energy Efficient Beamforming in Multibeam Satellite Systems
Lin, Zhi; An, Kang; Niu, Hehao et al

in IEEE Transactions on Aerospace and Electronic Systems (2022)

Motivated by the fact that both security and energy efficiency are the fundamental requirements and design targets of future satellite communications, this letter investigates secure energy efficient ... [more ▼]

Motivated by the fact that both security and energy efficiency are the fundamental requirements and design targets of future satellite communications, this letter investigates secure energy efficient beamforming in multibeam satellite systems, where the satellite user in each beam is surrounded by an eavesdropper attempting to intercept the confidential information. To simul- taneously improve the transmission security and reduce power consumption, our design objective is to maximize the system secrecy energy efficiency (SEE) under the constraint of total transmit power budget. Different from the existing schemes with high complexity, we propose an alternating optimization scheme to address the SEE problem by decomposing the original nonconvex problem into subproblems. Specifically, we first utilize the signal- to-leakage-plus-noise ratio (SLNR) metric to obtain closed-form normalized beamforming weight vectors, while the successive convex approximation (SCA) method is used to efficiently solve the power allocation subproblem. Then, an iterative algorithm is proposed to obtain the suboptimal solutions. Finally, simulation results are provided to verify the superiority of the proposed scheme compared to the benchmark schemes [less ▲]

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See detailGRN Mutations Are Associated with Lewy Body Dementia
Reho, Paolo; Koga, Shunsuke; Shah, Zalak et al

in Movement Disorders (2022)

ABSTRACT Background Loss-of-function mutations in GRN are a cause of familial frontotemporal dementia, and common variants within the gene have been associated with an increased risk of developing ... [more ▼]

ABSTRACT Background Loss-of-function mutations in GRN are a cause of familial frontotemporal dementia, and common variants within the gene have been associated with an increased risk of developing Alzheimer's disease and Parkinson's disease. Although TDP-43-positive inclusions are characteristic of GRN-related neurodegeneration, Lewy body copathology has also been observed in many GRN mutation carriers. Objective The objective of this study was to assess a Lewy body dementia (LBD) case–control cohort for pathogenic variants in GRN and to test whether there is an enrichment of damaging mutations among patients with LBD. Methods We analyzed whole-genome sequencing data generated for 2591 European-ancestry LBD cases and 4032 neurologically healthy control subjects to identify disease-causing mutations in GRN. Results We identified six heterozygous exonic GRN mutations in seven study participants (cases: n = 6; control subjects: n = 1). Each variant was predicted to be pathogenic or likely pathogenic. We found significant enrichment of GRN loss-of-function mutations in patients with LBD compared with control subjects (Optimized Sequence Kernel Association Test P = 0.0162). Immunohistochemistry in three definite LBD cases demonstrated Lewy body pathology and TDP-43-positive neuronal inclusions. Conclusions Our findings suggest that deleterious GRN mutations are a rare cause of familial LBD. © 2022 International Parkinson Movement Disorder Society. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA. [less ▲]

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See detailThe Interaction between HLA-DRB1 and Smoking in Parkinson's Disease Revisited
Domenighetti, Cloé; Douillard, Venceslas; Sugier, Pierre-Emmanuel et al

in Movement Disorders (2022)

Abstract Background Two studies that examined the interaction between HLA-DRB1 and smoking in Parkinson's disease (PD) yielded findings in opposite directions. Objective To perform a large-scale ... [more ▼]

Abstract Background Two studies that examined the interaction between HLA-DRB1 and smoking in Parkinson's disease (PD) yielded findings in opposite directions. Objective To perform a large-scale independent replication of the HLA-DRB1 × smoking interaction. Methods We genotyped 182 single nucleotide polymorphism (SNPs) associated with smoking initiation in 12 424 cases and 9480 controls to perform a Mendelian randomization (MR) analysis in strata defined by HLA-DRB1. Results At the amino acid level, a valine at position 11 (V11) in HLA-DRB1 displayed the strongest association with PD. MR showed an inverse association between genetically predicted smoking initiation and PD only in absence of V11 (odds ratio, 0.74, 95 confidence interval, 0.59–0.93, PInteraction = 0.028). In silico predictions of the influence of V11 and smoking-induced modifications of α-synuclein on binding affinity showed findings consistent with this interaction pattern. Conclusions Despite being one of the most robust findings in PD research, the mechanisms underlying the inverse association between smoking and PD remain unknown. Our findings may help better understand this association. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society [less ▲]

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See detailUniversity students’ friendship networks: Ambivalence and the role of attachment and personality
Schwind, Lena; Albert, Isabelle UL

in Trends in Psychology (2022), online first

Given the importance of friendships throughout the life span and the possible experience of ambivalence within these relationships, the present study aims at examining the role that attachment and ... [more ▼]

Given the importance of friendships throughout the life span and the possible experience of ambivalence within these relationships, the present study aims at examining the role that attachment and personality dimensions may play in this experience. University students (N = 87) completed an online survey, including the Big Five Inventory-10 (BFI-10), the Attachment Style Questionnaire (ASQ), as well as a two-item scale and an emotion checklist as two measures of ambivalence towards their friends. The correlation analysis revealed significant correlations between the ambivalence measures and secure attachment, fearful attachment, neuroticism, and agreeableness. A subsequent regression analysis demonstrated that fearful attachment, neuroticism, agreeableness, and gender can explain a considerable amount of variation in the degree of ambivalence. The results indicate that both certain attachment dimensions and certain personality dimensions predict the experience of ambivalence, although their importance may vary depending on the object of ambivalence. [less ▲]

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See detailEnergy Efficiency Optimization for Backscatter Enhanced NOMA Cooperative V2X Communications under Imperfect CSI
Khan, Wali Ullah UL; Jamshed, Muhammad Ali; Lagunas, Eva UL et al

in IEEE Transactions on Intelligent Transportation Systems (2022)

Automotive-Industry 5.0 will use beyond fifth-generation (B5G) technologies to provide robust, computationally intelligent, and energy-efficient data sharing among various onboard sensors, vehicles, and ... [more ▼]

Automotive-Industry 5.0 will use beyond fifth-generation (B5G) technologies to provide robust, computationally intelligent, and energy-efficient data sharing among various onboard sensors, vehicles, and other devices. Recently, ambient backscatter communications (AmBC) have gained significant interest in the research community for providing battery-free communications. AmBC can modulate useful data and reflect it towards near devices using the energy and frequency of existing RF signals. However, obtaining channel state information (CSI) for AmBC systems would be very challenging due to no pilot sequences and limited power. As one of the latest members of multiple access technology, non-orthogonal multiple access (NOMA) has emerged as a promising solution for connecting large-scale devices over the same spectral resources in B5G wireless networks. Under imperfect CSI, this paper provides a new optimization framework for energy-efficient transmission in AmBC enhanced NOMA cooperative vehicle-to-everything (V2X) networks. We simultaneously minimize the total transmit power of the V2X network by optimizing the power allocation at BS and reflection coefficient at backscatter sensors while guaranteeing the individual quality of services. The problem of total power minimization is formulated as non-convex optimization and coupled on multiple variables, making it complex and challenging. Therefore, we first decouple the original problem into two sub-problems and convert the nonlinear rate constraints into linear constraints. Then, we adopt the iterative sub-gradient method to obtain an efficient solution. For comparison, we also present a conventional NOMA cooperative V2X network without AmBC. Simulation results show the benefits of our proposed AmBC enhanced NOMA cooperative V2X network in terms of total achievable energy efficiency. [less ▲]

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See detailA Secure Data Sharing Scheme in Community Segmented Vehicular Social Networks for 6G
Khowaja, Sunder Ali; Khuwaja, Parus; Dev, Kapal et al

in IEEE Transactions on Industrial Informatics (2022)

The use of aerial base stations, AI cloud, and satellite storage can help manage location, traffic, and specific application-based services for vehicular social networks. However, sharing of such data ... [more ▼]

The use of aerial base stations, AI cloud, and satellite storage can help manage location, traffic, and specific application-based services for vehicular social networks. However, sharing of such data makes the vehicular network vulnerable to data and privacy leakage. In this regard, this article proposes an efficient and secure data sharing scheme using community segmentation and a blockchain-based framework for vehicular social networks. The proposed work considers similarity matrices that employ the dynamics of structural similarity, modularity matrix, and data compatibility. These similarity matrices are then passed through stacked autoencoders that are trained to extract encoded embedding. A density-based clustering approach is then employed to find the community segments from the information distances between the encoded embeddings. A blockchain network based on the Hyperledger Fabric platform is also adopted to ensure data sharing security. Extensive experiments have been carried out to evaluate the proposed data-sharing framework in terms of the sum of squared error, sharing degree, time cost, computational complexity, throughput, and CPU utilization for proving its efficacy and applicability. The results show that the CSB framework achieves a higher degree of SD, lower computational complexity, and higher throughput. [less ▲]

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See detailGeneralising from conventional pipelines using deep learning in high‑throughput screening workfows
Garcia Santa Cruz, Beatriz UL; Sölter, Jan; Gomez Giro, Gemma UL et al

in Scientific Reports (2022)

The study of complex diseases relies on large amounts of data to build models toward precision medicine. Such data acquisition is feasible in the context of high-throughput screening, in which the quality ... [more ▼]

The study of complex diseases relies on large amounts of data to build models toward precision medicine. Such data acquisition is feasible in the context of high-throughput screening, in which the quality of the results relies on the accuracy of the image analysis. Although state-of-the-art solutions for image segmentation employ deep learning approaches, the high cost of manually generating ground truth labels for model training hampers the day-to-day application in experimental laboratories. Alternatively, traditional computer vision-based solutions do not need expensive labels for their implementation. Our work combines both approaches by training a deep learning network using weak training labels automatically generated with conventional computer vision methods. Our network surpasses the conventional segmentation quality by generalising beyond noisy labels, providing a 25% increase of mean intersection over union, and simultaneously reducing the development and inference times. Our solution was embedded into an easy-to-use graphical user interface that allows researchers to assess the predictions and correct potential inaccuracies with minimal human input. To demonstrate the feasibility of training a deep learning solution on a large dataset of noisy labels automatically generated by a conventional pipeline, we compared our solution against the common approach of training a model from a small manually curated dataset by several experts. Our work suggests that humans perform better in context interpretation, such as error assessment, while computers outperform in pixel-by-pixel fne segmentation. Such pipelines are illustrated with a case study on image segmentation for autophagy events. This work aims for better translation of new technologies to real-world settings in microscopy-image analysis. [less ▲]

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See detailParental Assortative Mating and the Intergenerational Transmission of Human Capital
Bingley, Paul; Cappellari, Lorenzo; Tatsiramos, Konstantinos UL

in Labour Economics (2022), 77

We study the contribution of parental educational assortative mating to the intergenerational transmission of educational attainment. We develop an empirical model for educational correlations within the ... [more ▼]

We study the contribution of parental educational assortative mating to the intergenerational transmission of educational attainment. We develop an empirical model for educational correlations within the family in which parental educational sorting can translate into intergenerational transmission jointly by both parents, or transmission can originate from each parent independently. Estimating the model using educational attainment from Danish population-based administrative data for over 400,000 families, we find that on aver- age 75 percent of the intergenerational correlation in education is driven by the joint contribution of the par- ents. We also document a 38 percent decline of assortative mating in education for parents born between the early 1920s and the early 1950s. While the raw correlations also show decreases in father- and mother- specific intergenerational transmissions of educational attainment, our model shows that once we decompose all factors of intergenerational mobility, the share of intergenerational transmission accounted for by parent-specific factors increased from 7 to 27 percent; an increase compensated by a corresponding fall in joint intergenerational transmission from both parents, leaving total intergenerational persistence un- changed. The mechanisms of intergenerational transmission have changed, with an increased importance of one-to-one parent-child relationships. [less ▲]

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See detailMean-field theory for the structure of strongly interacting active liquids
Tociu, Laura; Rassolov, Gregory; Fodor, Etienne UL et al

in Journal of Chemical Physics (2022)

Active systems, which are driven out of equilibrium by local non-conservative forces, exhibit unique behaviors and structures with potential utility for the design of novel materials. An important and ... [more ▼]

Active systems, which are driven out of equilibrium by local non-conservative forces, exhibit unique behaviors and structures with potential utility for the design of novel materials. An important and difficult challenge along the path toward this goal is to precisely predict how the structure of active systems is modified as their driving forces push them out of equilibrium. Here, we use tools from liquid-state theories to approach this challenge for a classic minimal active matter model. First, we construct a nonequilibrium mean-field framework that can predict the structure of systems of weakly interacting particles. Second, motivated by equilibrium solvation theories, we modify this theory to extend it with surprisingly high accuracy to systems of strongly interacting particles, distinguishing it from most existing similarly tractable approaches. Our results provide insight into spatial organization in strongly interacting out-of-equilibrium systems. [less ▲]

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See detailSelf-regulation of phenotypic noise synchronizes emergent organization and active transport in confluent microbial environments
Dhar, Jayabrata UL; Thai, Le Phuong Anh UL; Ghoshal, Arkajyoti UL et al

in Nature Physics (2022)

The variation associated with different observable characteristics—phenotypes—at the cellular scale underpins homeostasis and the fitness of living systems. However, if and how these noisy phenotypic ... [more ▼]

The variation associated with different observable characteristics—phenotypes—at the cellular scale underpins homeostasis and the fitness of living systems. However, if and how these noisy phenotypic traits shape properties at the population level remains poorly understood. Here we report that phenotypic noise self-regulates with growth and coordinates collective structural organization, the kinetics of topological defects and the emergence of active transport around confluent colonies. We do this by cataloguing key phenotypic traits in bacteria growing under diverse conditions. Our results reveal a statistically precise critical time for the transition from a monolayer biofilm to a multilayer biofilm, despite the strong noise in the cell geometry and the colony area at the onset of the transition. This reveals a mitigation mechanism between the noise in the cell geometry and the growth rate that dictates the narrow critical time window. By uncovering how rectification of phenotypic noise homogenizes correlated collective properties across colonies, our work points at an emergent strategy that confluent systems employ to tune active transport, buffering inherent heterogeneities associated with natural cellular environment settings. [less ▲]

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See detailLSTM-Based Distributed Conditional Generative Adversarial Network for Data-Driven 5G-Enabled Maritime UAV Communications
Rasheed, Iftikhar; Asif, Muhammad; Ihsan, Asim et al

in IEEE Transactions on Intelligent Transportation Systems (2022)

5G enabled maritime unmanned aerial vehicle (UAV) communication is one of the important applications of 5G wireless network which requires minimum latency and higher reliability to support mission ... [more ▼]

5G enabled maritime unmanned aerial vehicle (UAV) communication is one of the important applications of 5G wireless network which requires minimum latency and higher reliability to support mission-critical applications. Therefore, lossless reliable communication with a high data rate is the key requirement in modern wireless communication systems. These all factors highly depend upon channel conditions. In this work, a channel model is proposed for air-to-surface link exploiting millimeter wave (mmWave) for 5G enabled maritime unmanned aerial vehicle (UAV) communication. Firstly, we will present the formulated channel estimation method which directly aims to adopt channel state information (CSI) of mmWave from the channel model inculcated by UAV operating within the Long Short Term Memory (LSTM)-Distributed Conditional generative adversarial network (DCGAN) i.e. (LSTM-DCGAN) for each beamforming direction. Secondly, to enhance the applications for the proposed trained channel model for the spatial domain, we have designed an LSTM-DCGAN based UAV network, where each one will learn mmWave CSI for all the distributions. Lastly, we have categorized the most favorable LSTM-DCGAN training method and emanated certain conditions for our UAV network to increase the channel model learning rate. Simulation results have shown that the proposed LSTM-DCGAN based network is vigorous to the error generated through local training. A detailed comparison has been done with the other available state-of-the-art CGAN network architectures i.e. stand-alone CGAN (without CSI sharing), Simple CGAN (with CSI sharing), multi-discriminator CGAN, federated learning CGAN and DCGAN. Simulation results have shown that the proposed LSTM-DCGAN structure demonstrates higher accuracy during the learning process and attained more data rate for downlink transmission as compared to the previous state of artworks. [less ▲]

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See detailSome Prevalent Sets in Multifractal Analysis: How Smooth is Almost Every Function in T_p^\alpha(x)
Loosveldt, Laurent UL; Nicolay, Samuel

in Journal of Fourier Analysis and Applications (2022), 28(4),

We present prevalent results concerning generalized versions of the $T_p^\alpha$ spaces, initially introduced by Calderón and Zygmund. We notably show that the logarithmic correction appearing in the ... [more ▼]

We present prevalent results concerning generalized versions of the $T_p^\alpha$ spaces, initially introduced by Calderón and Zygmund. We notably show that the logarithmic correction appearing in the quasi-characterization of such spaces is mandatory for almost every function; it is in particular true for the Hölder spaces, for which the existence of the correction was showed necessary for a specific function. We also show that almost every function from $T_p^α (x0 )$ has α as generalized Hölder exponent at $x_0$. [less ▲]

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See detailLinear system identifiability from single-cell data
Aalto, Atte UL; Lamoline, François UL; Goncalves, Jorge UL

in Systems and Control Letters (2022), 165

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See detailBearing the cost of politics: Consumer prices and welfare in Russia
Hinz, Julian; Monastyrenko, Evgenii UL

in Journal of International Economics (2022), 137

In August 2014, the Russian Federation implemented an embargo on select food and agricultural imports from Western countries in response to previously imposed economic sanctions. In this paper we quantify ... [more ▼]

In August 2014, the Russian Federation implemented an embargo on select food and agricultural imports from Western countries in response to previously imposed economic sanctions. In this paper we quantify the effect of this embargo on consumer prices and welfare in Russia. We provide evidence for the direct effect on monthly consumer prices with a difference-in-differences approach. The embargo caused prices of embargoed goods to rise by up to 7.7% – 14.9% in the short run and by on average 2.6% – 8.1% until at least 2016. The results further suggest the shock was transmitted to non-embargoed sectors through domestic input-output linkages. We then construct a general equilibrium Ricardian model of trade with input-output linkages and goods that are tradable, non-tradable or embargoed. The model-based counterfactual analysis predicts the overall price index in Russia to have increased by 0.33% and welfare to have declined by 1.84% due to the embargo. [less ▲]

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See detailDetermination of the angle of repose of hard metal granules
Just, Marvin UL; Medina Peschiutta, Alexander UL; Hippe, Frankie et al

in Powder Technology (2022), 407

The angle of repose is a quantity that delivers direct information about the flowability of granular material. It is therefore desirable to have a reliable experimental method for its determination. Based ... [more ▼]

The angle of repose is a quantity that delivers direct information about the flowability of granular material. It is therefore desirable to have a reliable experimental method for its determination. Based on the well-established funnel method with continuous mass flow, an extension is introduced which allows increasing the precision and reproducibility of the angle of repose measurements. A modified experimental setup is presented which exploits asymmetries in the alignment of the mechanical setup to gain more precision in the determination of the angle of repose. This experimental setup is combined with an evaluation method based on automated image analysis. The first results for a set of metal powders are presented. [less ▲]

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See detailSpeculative Trading and Bubbles: Evidence from the Art Market
Penasse, Julien UL; Renneboog, Luc

in MANAGEMENT SCIENCE (2022), 68(7), 4755-5555

We argue that extrapolative expectations drive boom–bust cycles in the postwarart market. Price run-ups coincide with increases in demand fundamentals but are fol-lowed by predictable busts. Predictable ... [more ▼]

We argue that extrapolative expectations drive boom–bust cycles in the postwarart market. Price run-ups coincide with increases in demand fundamentals but are fol-lowed by predictable busts. Predictable changes account for about half of the variance offive-year price changes. High prices coincide with many attributes of speculative bubbles:trading volume, the share of short-term trades, the share of postwar art, and volatility areall higher during booms. In addition, short-term transactions underperform long-termtransactions. Survey evidence further confirms the link between beliefs, prices, and volumedynamics as in models in which extrapolative beliefs fuel speculative bubbles. [less ▲]

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See detailOpinion Statement ECJ-TF 2/2022 on the Decision of 27 January 2022 in European Commission v. Kingdom of Spain (Form 720) (Case C-788/19)
Kofler, Georg; García Prats, Alfredo; Haslehner, Werner UL et al

in European Taxation (2022), 62(7), 304-310

In this CFE Opinion Statement, the CFE ECJ Task Force comments on the decision of 27 January 2022 in European Commission v. Kingdom of Spain (Form 720) (Case C-788/19) on the lack of proportionality of ... [more ▼]

In this CFE Opinion Statement, the CFE ECJ Task Force comments on the decision of 27 January 2022 in European Commission v. Kingdom of Spain (Form 720) (Case C-788/19) on the lack of proportionality of the consequences derived from the failure to provide information concerning assets or rights held in other Member States of the European Union or the European Economic Area. [less ▲]

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See detailA Survey on Vehicular Task Offloading: Classification, Issues, and Challenges
Ahmed, Manzoor; Raza, Salman; Mirza, Muhammad Ayzed et al

in Journal of King Saud University - Computer and Information Sciences (2022)

Emerging vehicular applications with strict latency and reliability requirements pose high computing requirements, and current vehicles’ computational resources are not adequate to meet these demands. In ... [more ▼]

Emerging vehicular applications with strict latency and reliability requirements pose high computing requirements, and current vehicles’ computational resources are not adequate to meet these demands. In this scenario, vehicles can get help to process tasks from other resource-rich computing platforms, including nearby vehicles, fixed edge servers, and remote cloud servers. Nonetheless, different vehicular communication network (VCN) modes need to be utilized to access these computing resources, improving applications and networks’ performance and quality of service (QoS). In this paper, we present a comprehensive survey on the vehicular task offloading techniques under a communication perspective, i.e., vehicle to vehicle (V2V), vehicle to roadside infrastructure (V2I), and vehicle to everything (V2X). For the task/computation offloading, we present the classification of methods under the V2V, V2I, and V2X communication domains. Besides, the task/computation offloading categories are each sub-categorized according to their schemes’ objectives. Furthermore, the literature on vehicular task offloading is elaborated, compared, and analyzed from the perspectives of approaches, objectives, merits, demerits, etc. Finally, we highlight the open research challenges in this field and predict future research trends. [less ▲]

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See detailPréserve-moi ! Des journaux intimes à ceux de confinement dans les archives du Web
Schafer, Valerie UL

in Le Temps des Médias (2022)

Souvent éphémères, les pages personnelles, les blogs et aujourd’hui les écritures de soi et intimes sur les réseaux socio-numériques, jusqu’aux journaux de confinement nés lors de la crise COVID, sont ... [more ▼]

Souvent éphémères, les pages personnelles, les blogs et aujourd’hui les écritures de soi et intimes sur les réseaux socio-numériques, jusqu’aux journaux de confinement nés lors de la crise COVID, sont toutefois partiellement préservés dans les archives du Web. En explorant leur conservation, notamment au sein de la Bibliothèque nationale de France, et les limites et défis que posent ces sources nativement numériques, il s’agit de saisir les enjeux de préservation de ces contenus personnels, intimes, littéraires, vernaculaires, multimédias, mais aussi les possibilités de recherche qu’ils offrent pour l’histoire du numérique et de ses cultures. [less ▲]

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See detailIs There a Need for a Directive on Pillar Two? A Few Normative Comments.
Haslehner, Werner UL

in Intertax, International Tax Review (2022), 50(6/7), 527-530

Poland’s request to link the entry into force of the Pillar 2 Directive to an international agreement on Pillar 1 raises fundamental questions about the European constitutional structure. Beyond the mere ... [more ▼]

Poland’s request to link the entry into force of the Pillar 2 Directive to an international agreement on Pillar 1 raises fundamental questions about the European constitutional structure. Beyond the mere legality of such a link, this contribution seeks to respond to some normative concerns related to the creation of such secondary legislation. [less ▲]

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See detailImpact of phase-noise and spatial correlation on double-RIS-assisted multiuser MISO networks
Abdullah, Zaid UL; Papazafeiropoulos, Anastasios; Kisseleff, Steven UL et al

in IEEE Wireless Communications Letters (2022), 11(7), 1473-1477

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See detailBlack-box Safety Analysis and Retraining of DNNs based on Feature Extraction and Clustering
Attaoui, Mohammed Oualid UL; Fahmy, Hazem UL; Pastore, Fabrizio UL et al

in ACM Transactions on Software Engineering and Methodology (2022)

Deep neural networks (DNNs) have demonstrated superior performance over classical machine learning to support many features in safety-critical systems. Although DNNs are now widely used in such systems (e ... [more ▼]

Deep neural networks (DNNs) have demonstrated superior performance over classical machine learning to support many features in safety-critical systems. Although DNNs are now widely used in such systems (e.g., self driving cars), there is limited progress regarding automated support for functional safety analysis in DNN-based systems. For example, the identification of root causes of errors, to enable both risk analysis and DNN retraining, remains an open problem. In this paper, we propose SAFE, a black-box approach to automatically characterize the root causes of DNN errors. SAFE relies on a transfer learning model pre-trained on ImageNet to extract the features from error-inducing images. It then applies a density-based clustering algorithm to detect arbitrary shaped clusters of images modeling plausible causes of error. Last, clusters are used to effectively retrain and improve the DNN. The black-box nature of SAFE is motivated by our objective not to require changes or even access to the DNN internals to facilitate adoption. Experimental results show the superior ability of SAFE in identifying different root causes of DNN errors based on case studies in the automotive domain. It also yields significant improvements in DNN accuracy after retraining, while saving significant execution time and memory when compared to alternatives. [less ▲]

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See detailGöttliche Protokolle, Bitcoin-Jünger und schattenhafte Herrscher: Über die religiösen Anwandlungen und ideologischen Verstrickungen der Blockchain-Technologie
Becker, Katrin UL

in Jahrbuch für Technikphilosophie (2022), 8

Starting with an overview of the functioning and applications of blockchain, the paper sheds light on the core promise of this technology, namely, to overcome of the need for institutionally legitimized ... [more ▼]

Starting with an overview of the functioning and applications of blockchain, the paper sheds light on the core promise of this technology, namely, to overcome of the need for institutionally legitimized intermediaries and to provide the subject with new possibilities for self-determined management of its own and communal lives. With reference to the philosopher Pierre Legendre, the paper first analyses the worldview underlying this promise in terms of cultural theory. Then the focus is directed towards the ideological entanglements as well as the religious elements that one encounters in the discursive environment of the technology. In view of this, it will be critically questioned to what extent one can really speak of decentralization and the abolition of middlemen. The paper thus aims to show why blockchain technology and its fields of applications require a critical discussion. [less ▲]

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See detailResource Allocation in Heterogeneously-Distributed Joint Radar-Communications Under Asynchronous Bayesian Tracking Framework
Wu, Linlong; Mishra, Kumar Vijay; Mysore Rama Rao, Bhavani Shankar UL et al

in IEEE Journal on Selected Areas in Communications (2022), 40(7), 2026-2042

Optimal allocation of shared resources is key to deliver the promise of jointly operating radar and communications systems. In this paper, unlike prior works which examine synergistic access to resources ... [more ▼]

Optimal allocation of shared resources is key to deliver the promise of jointly operating radar and communications systems. In this paper, unlike prior works which examine synergistic access to resources in colocated joint radar-communications or among identical systems, we investigate this problem for a distributed system comprising heterogeneous radars and multi-tier communications. In particular, we focus on resource allocation in the context of multi-target tracking (MTT) while maintaining stable communications connections. By simultaneously allocating the available power, dwell time and shared bandwidth, we improve the MTT performance under a Bayesian tracking framework and guarantee the communications throughput. Our a lter n ating allo c ation of h eterogene o us r esources (ANCHOR) approach solves the resulting non-convex problem based on the alternating optimization method that monotonically improves the Bayesian Cramér-Rao bound. Numerical experiments demonstrate that ANCHOR significantly improves the tracking error over two baseline allocations and stability under different target scenarios and radar-communications network distributions. [less ▲]

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See detailFurther resource multiplication at more advanced ages? Interactions between education, parental socioeconomic status, and age in their impacts upon health
Settels, Jason UL

in Sociology Compass (2022)

While scholarship has shown that socioeconomic status creates fine-grained gradients in health, there is debate regarding whether having higher amounts of one socioeconomic resource amplifies (resource ... [more ▼]

While scholarship has shown that socioeconomic status creates fine-grained gradients in health, there is debate regarding whether having higher amounts of one socioeconomic resource amplifies (resource multiplication) or reduces (resource substitution) the health benefits of  one's other socioeconomic resources. A further question is whether these processes are accentuated or diminished at more advanced ages. Using the 2016 and 2018 waves of the United States General Social Survey (N = 2995) and logistic regression analyses, this study reveals processes of resource multiplication between respondents' education and both parental education and parental occupational prestige in their effects upon self-rated health. Furthermore, these processes are accentuated at more advanced ages. Additionally, these interactive effects remain significant after controlling for respondent-level total family income and occupational prestige, suggesting mechanisms beyond actualized socioeconomic circumstances. These findings raise concerns regarding less educated older persons coming from less advantaged backgrounds. Accordingly, policies and programs should help equalize social circumstances early in the life course, to produce more salubrious trajectories with advancing age. [less ▲]

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See detailFading-ratio-based selection for massive MIMO systems under line-of-sight propagation
Chaves, Rafael da Silva; Cetin, Ediz; Lima, Markus V. S. et al

in Wireless Networks (2022)

Massive multiple-input multiple-output (MIMO) enables increased throughput by using spatial multiplexing. However, the throughput may severely degrade when the number of users served by a single base ... [more ▼]

Massive multiple-input multiple-output (MIMO) enables increased throughput by using spatial multiplexing. However, the throughput may severely degrade when the number of users served by a single base station increases, especially under line-of-sight (LoS) propagation. Selecting users is a possible solution to deal with this problem. In the literature, the user selection algorithms can be divided into two classes: small-scale fading aware (SSFA) and large scale fading aware (LSFA) algorithms. The LSFA algorithms are good solutions for massive MIMO systems under non LoS propagation since the small-scale fading does not affect the system performance under this type of propagation. For the LoS case, the small scale fading has a great impact on the system performance, requiring the use of SSFA algorithms. However, disregarding the large-scale fading is equivalent to assuming that all users are equidistant from the base station and experience the same level of shadowing, which is not a reasonable approximation in practical applications. To address this shortcoming, a new user selection algorithm called the fading-ratio-based selection (FRBS) is proposed. FRBS considers both fading information to drop those users that induce the highest interference to the remaining ones. Simulation results considering LoS channels show that using FRBS yields near optimum downlink throughput, which is similar to that of the state-of-the-art algorithm, but with much lower computational complexity. Moreover, the use of FRBS with zero forcing precoder resulted in 26.28% improvement in the maximum throughput when compared with SSFA algorithms, and 35.39% improvement when compared with LSFA algorithms. [less ▲]

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See detailDigBug—Pre/post-processing operator selection for accurate bug localization
Kim, Kisub; Ghatpande, Sankalp UL; Liu, Kui et al

in Journal of Systems and Software (2022), 189

Bug localization is a recurrent maintenance task in software development. It aims at identifying relevant code locations (e.g., code files) that must be inspected to fix bugs. When such bugs are reported ... [more ▼]

Bug localization is a recurrent maintenance task in software development. It aims at identifying relevant code locations (e.g., code files) that must be inspected to fix bugs. When such bugs are reported by users, the localization process become often overwhelming as it is mostly a manual task due to incomplete and informal information (written in natural languages) available in bug reports. The research community has then invested in automated approaches, notably using Information Retrieval techniques. Unfortunately, reported performance in the literature is still limited for practical usage. Our key observation, after empirically investigating a large dataset of bug reports as well as workflow and results of state-of-the-art approaches, is that most approaches attempt localization for every bug report without considering the different characteristics of the bug reports. We propose DigBug as a straightforward approach to specialized bug localization. This approach selects pre/post-processing operators based on the attributes of bug reports; and the bug localization model is parameterized in accordance as well. Our experiments confirm that departing from “one-size-fits-all” approaches, DigBug outperforms the state-of-the-art techniques by 6 and 14 percentage points, respectively in terms of MAP and MRR on average. [less ▲]

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See detailMicrogliosis: a double-edged sword in the control of food intake
Salvi, Juliette; Andreoletti, Pierre; Audinat, Etienne et al

in FEBS Journal (2022)

Maintaining energy balance is essential for survival and health. This physiological function is controlled by the brain, which adapts food intake to energy needs. Indeed, the brain constantly receives a ... [more ▼]

Maintaining energy balance is essential for survival and health. This physiological function is controlled by the brain, which adapts food intake to energy needs. Indeed, the brain constantly receives a multitude of biological signals that are derived from digested foods or that originate from the gastrointestinal tract, energy stores (liver and adipose tissues) and other metabolically active organs (muscles). These signals, which include circulating nutrients, hormones and neuronal inputs from the periphery, collectively provide information on the overall energy status of the body. In the brain, several neuronal populations can specifically detect these signals. Nutrient-sensing neurons are found in discrete brain areas and are highly enriched in the hypothalamus. In turn, specialized brain circuits coordinate homeostatic responses acting mainly on appetite, peripheral metabolism, activity and arousal. Accumulating evidence shows that hypothalamic microglial cells located at the vicinity of these circuits can influence the brain control of energy balance. However, microglial cells could have opposite effects on energy balance, that is homeostatic or detrimental, and the conditions for this shift are not totally understood yet. One hypothesis relies on the extent of microglial activation, and nutritional lipids can considerably change it. [less ▲]

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See detailThe role of common genetic variation in presumed monogenic epilepsies
Campbell, Ciarán; Leu, Costin; Feng, Yen-Chen Anne et al

in eBioMedicine (2022), 81

Summary: Background The developmental and epileptic encephalopathies (DEEs) are the most severe group of epilepsies which co-present with developmental delay and intellectual disability (ID). DEEs usually ... [more ▼]

Summary: Background The developmental and epileptic encephalopathies (DEEs) are the most severe group of epilepsies which co-present with developmental delay and intellectual disability (ID). DEEs usually occur in people without a family history of epilepsy and have emerged as primarily monogenic, with damaging rare mutations found in 50% of patients. Little is known about the genetic architecture of patients with DEEs in whom no pathogenic variant is identified. Polygenic risk scoring (PRS) is a method that measures a person's common genetic burden for a trait or condition. Here, we used PRS to test whether genetic burden for epilepsy is relevant in individuals with DEEs, and other forms of epilepsy with ID. Methods: Genetic data on 2,759 cases with DEEs, or epilepsy with ID presumed to have a monogenic basis, and 447,760 population-matched controls were analysed. We compared PRS for ‘all epilepsy’, ‘focal epilepsy’, and ‘genetic generalised epilepsy’ (GGE) between cases and controls. We performed pairwise comparisons between cases stratified for identifiable rare deleterious genetic variants and controls. Findings 0.0002) relative to controls, which explain between 0.08% and 3.3% of phenotypic variance. PRS was increased in cases both with and without an identified deleterious variant of major effect, and there was no significant difference in PRS between the two groups. Interpretation: We provide evidence that common genetic variation contributes to the aetiology of DEEs and other forms of epilepsy with ID, even when there is a known pathogenic variant of major effect. These results provide insight into the genetic underpinnings of the severe epilepsies and warrant a shift in our understanding of the aetiology of the DEEs as complex, rather than monogenic, disorders. [less ▲]

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