References of "2021"
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See detailBrownian Loops, Layering Fields and Imaginary Gaussian Multiplicative Chaos
Camia, Federico; Gandolfi, Alberto; Peccati, Giovanni UL et al

in Communications in Mathematical Physics (2021), In press

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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 (2021)

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See detailConFuzzius: A Data Dependency-Aware Hybrid Fuzzer for Smart Contracts
Ferreira Torres, Christof UL; Iannillo, Antonio Ken UL; Gervais, Arthur et al

in European Symposium on Security and Privacy, Vienna 7-11 September 2021 (2021, September)

Smart contracts are Turing-complete programs that are executed across a blockchain. Unlike traditional programs, once deployed, they cannot be modified. As smart contracts carry more value, they become ... [more ▼]

Smart contracts are Turing-complete programs that are executed across a blockchain. Unlike traditional programs, once deployed, they cannot be modified. As smart contracts carry more value, they become more of an exciting target for attackers. Over the last years, they suffered from exploits costing millions of dollars due to simple programming mistakes. As a result, a variety of tools for detecting bugs have been proposed. Most of these tools rely on symbolic execution, which may yield false positives due to over-approximation. Recently, many fuzzers have been proposed to detect bugs in smart contracts. However, these tend to be more effective in finding shallow bugs and less effective in finding bugs that lie deep in the execution, therefore achieving low code coverage and many false negatives. An alternative that has proven to achieve good results in traditional programs is hybrid fuzzing, a combination of symbolic execution and fuzzing. In this work, we study hybrid fuzzing on smart contracts and present ConFuzzius, the first hybrid fuzzer for smart contracts. ConFuzzius uses evolutionary fuzzing to exercise shallow parts of a smart contract and constraint solving to generate inputs that satisfy complex conditions that prevent evolutionary fuzzing from exploring deeper parts. Moreover, ConFuzzius leverages dynamic data dependency analysis to efficiently generate sequences of transactions that are more likely to result in contract states in which bugs may be hidden. We evaluate the effectiveness of ConFuzzius by comparing it with state-of-the-art symbolic execution tools and fuzzers for smart contracts. Our evaluation on a curated dataset of 128 contracts and a dataset of 21K real-world contracts shows that our hybrid approach detects more bugs than state-of-the-art tools (up to 23%) and that it outperforms existing tools in terms of code coverage (up to 69%). We also demonstrate that data dependency analysis can boost bug detection up to 18%. [less ▲]

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See detailNo more Piecemeal Tactics
Kafteranis, Dimitrios UL; Robert, Brochhaus

E-print/Working paper (2021)

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See detailSmall in size, great in significance: conspicilla and perspicilla in the visual arts of the Low Countries around 1600
Koeleman, Floor UL

Scientific Conference (2021, July)

A largely forgotten constcamer painting from the early seventeenth century shows eyeglasses and a telescope in close proximity. The inclusion of these extensions of sight in The Five Senses of the Musée ... [more ▼]

A largely forgotten constcamer painting from the early seventeenth century shows eyeglasses and a telescope in close proximity. The inclusion of these extensions of sight in The Five Senses of the Musée Magnin (Dijon) seems to allude to the implicit link between the two. As tools to observe with and through, these instruments visualize the limits of human perception and the ability to alter the scale of the visible world. The Five Senses was created in Antwerp around the same time the telescope first appeared in textual sources, namely 1608. However, the optical instrument is likely to have existed for years by then. This paper investigates if any references to the telescope in the visual arts predate the first written evidence of its invention. For artists the early telescope was probably not that challenging an object to represent. The exterior, a simple tube characterized by a diaphragm, housed two lenses made by the same glass industry that manufactured eyeglasses. This paper takes a closer look at the imagery of eyeglasses and telescopes, depicted in the visual arts of the late sixteenth and early seventeenth centuries. The meaning assigned to these instruments can be inferred from the context in which they are presented and their relative scale. Together eyeglasses and telescopes feature prominently in constcamer paintings dedicated to visual perception, understood both physically and metaphysically. While the exact date of creation remains subject to debate, The Five Senses probably contains the earliest known depiction of a telescope – true to scale. [less ▲]

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See detailMeasuring multicultural ideology: Scale development and validation in different languages and contexts
Stogianni, Maria UL; Schmidt, Lea Marie; Murdock, Elke UL et al

Scientific Conference (2021, July)

Increased migration has led to the formation of culturally diverse societies in many places around the world. The concept of Multicultural Ideology incorporates two values as a way to promote positive ... [more ▼]

Increased migration has led to the formation of culturally diverse societies in many places around the world. The concept of Multicultural Ideology incorporates two values as a way to promote positive intercultural relations: a) Diversity: the presence of ethnocultural diversity in the population and b) Equity: the right for equal participation of all cultural groups in the society. Both diversity and equity are necessary conditions for the success of multicultural policies. Culturally heterogeneous communities that do not support inclusion and equitable participation of all groups face the negative consequences of segregation and marginalization. In line with this notion, an international research consortium is developing a revised version of the Multicultural Ideology Scale to assess the endorsement of multicultural ideology in different national contexts. The scale aims to distinguish various attitudinal dimensions of multiculturalism, relevant to the acceptance of diversity and social inclusion of different ethnocultural groups: Cultural Maintenance, Social Interaction, Equity/Inclusion, Extent of Differences, Conflictual Relations, Essentialistic Boundaries. We present the first assessment of the new scale in the German language. The survey was administered online to a sample of native German citizens (N = 382) with different demographic characteristics. Our aim was to understand the attitude of native citizens towards cultural diversity and their willingness to have members of ethnic minority groups be included in the larger society. We investigated the factor structure of the scale, its psychometric properties, and the relationship between multicultural ideology and some individual difference variables, such as ethnic group attachment and social dominance orientation. [less ▲]

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See detailKnowledge assessment with concept maps: Opportunities and challenges
Rohles, Björn UL; Koenig, Vincent UL; Fischbach, Antoine UL et al

Scientific Conference (2021, July)

21st-century digital society poses tremendous challenges for education and assessment. Learners have to understand the complex relations between diverse topics and learn how to learn their entire lives ... [more ▼]

21st-century digital society poses tremendous challenges for education and assessment. Learners have to understand the complex relations between diverse topics and learn how to learn their entire lives. Concept mapping is a promising approach to address these issues. It is a method that uses concepts connected by labeled links to visualize a semantic network of knowledge. Concept mapping is predestined for a digital approach because it allows for easy interactive editing, innovative test items, and incorporation of multimodal information. Concept mapping is available for summative and formative assessment and, thus, provides the opportunity to become a vital part of modern education. The biggest advantage of concept mapping (i.e., a comprehensive and yet comprehensible visualization of complex relations) also represents the biggest challenge when it comes to assessment with - and scoring of - concept maps. The first challenge is the enormous amount of indicators used for scoring concept maps in assessment. A second challenge comes from the fact that educators using concept mapping in their assessment have to understand and interpret the indicators that are used in scoring concept maps. This presentation reports on a Ph.D. project that investigates digital concept mapping in the context of knowledge assessment from a user experience perspective. The results are based on, first, a comprehensive international systematic literature review on concept map scoring, and second, three empirical studies covering the needs and experiences of learners and educators in concept mapping. It presents key findings from the iterative user experience design of a concept mapping tool as part of the online assessment platform OASYS, an overview of indicators used in concept map scoring, and research opportunities in knowledge assessment with concept maps. Finally, it stresses the value that user experience design brings to knowledge assessment with concept maps. [less ▲]

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See detailLuxembourg
Leist, Anja UL

in Immergut, E.; Anderson, K.; Devitt, C. (Eds.) et al Health politics in Europe: A handbook (2021)

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See detailEnergy Efficiency Optimization Technique for SWIPT-enabled Multi-Group Multicasting Systems with Heterogeneous Users
Gautam, Sumit UL; Chatzinotas, Symeon UL; Ottersten, Björn UL

in The international Conference on Acoustics, Speech, & Signal Processing (ICASSP) (2021, June)

We consider a multi-group (MG) multicasting (MC) system wherein a multi-antenna transmitter serves heterogeneous users capable of either information decoding (ID) or energy harvesting (EH), or both. In ... [more ▼]

We consider a multi-group (MG) multicasting (MC) system wherein a multi-antenna transmitter serves heterogeneous users capable of either information decoding (ID) or energy harvesting (EH), or both. In this context, we investigate a precoder design framework to explicitly serve the ID and EH users categorized within certain MC and EH groups. Specifically, the ID users are categorized within multiple MC groups while the EH users are a part of single (last) group. We formulate a problem to optimize the energy efficiency in the considered scenario under a quality-of-service (QoS) constraint. An algorithm based on Dinkelback method, slack-variable replacement, and second-order conic programming (SOCP)/semi-definite relaxation (SDR) is proposed to obtain a suitable solution for the above-mentioned fractional-objective dependent non-convex problem. Simulation results illustrate the benefits of proposed algorithm under several operating conditions and parameter values, while drawing a comparison between the two proposed methods. [less ▲]

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See detailA design strategy for phase synchronization in Precoding-enabled DVB-S2X user terminals
Martinez Marrero, Liz UL; Merlano Duncan, Juan Carlos UL; Querol, Jorge UL et al

Scientific Conference (2021, June)

This paper address the design of a phase tracking block for the DVB-S2X user terminals in a satellite precoding system. The spectral characteristics of the phase noise introduced by the oscillator, the ... [more ▼]

This paper address the design of a phase tracking block for the DVB-S2X user terminals in a satellite precoding system. The spectral characteristics of the phase noise introduced by the oscillator, the channel, and the thermal noise at the receiver are taken into account. Using the expected phase noise mask, the optimal parameters for a second-order PLL intended to track channel variations from the pilots are calculated. To validate the results a Simulink model was implemented considering the characteristics of the hardware prototype. The performance of the design was evaluated in terms of the accuracy and stability for the frame structure of superframe Format 2, as described in Annex E of DVB-S2X. [less ▲]

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See detailBoys don't cry (or do the dishes): Family size and the housework gender gap
Menta, Giorgia UL; Lepinteur, Anthony UL

in Journal of Economic Behavior and Organization (2021), 186

We here use data from the British Cohort Study (BCS) to link family size to age-16 children’s contribution to household chores and the adult housework gender gap. Assuming that home production is an ... [more ▼]

We here use data from the British Cohort Study (BCS) to link family size to age-16 children’s contribution to household chores and the adult housework gender gap. Assuming that home production is an increasing function of family size and using an instrument to account for the endogeneity of fertility, we show that larger families have a different effect on boys and girls at age 16: girls in large families are significantly more likely to contribute to housework, with no effect for boys. We then show that childhood family size affects the housework gender gap between the cohort members and their partners at age 34. Women who grew up in larger families are more likely to carry out a greater share of household tasks in adulthood, as compared to women from smaller families. In addition, growing up in a large family makes cohort members more likely to sort into households with a wider housework gender gap as adults. We show that the persistent effect of family size is due to the adoption of behaviours in line with traditional gender roles: a lower likelihood of employment and shorter commutes for women, along with a higher employment probability for their partners. [less ▲]

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See detailDemocracy, Freedom and Truth at a Time of Digital Disruption: An equation with three unknowns?
Danescu, Elena UL

in Višňovský, Ján; Radošinská, Jana (Eds.) Fake News Is Bad News - Hoaxes, Half-truths and the Nature of Today's Journalism (2021)

The pattern of a knowledge-based society relies to a large extent on digital technologies and intangible outputs and generate considerable transnational financial flows and gains. These technologies also ... [more ▼]

The pattern of a knowledge-based society relies to a large extent on digital technologies and intangible outputs and generate considerable transnational financial flows and gains. These technologies also play a key role in providing free access to data and information, encouraging citizen participation in public decision-making, fostering transparency and scrutiny of government action and mobilising new players capable of identifying alternative means of civic and political participation worldwide. At the same time, the increasingly impact of online platforms in manipulating transnational public debates, and the surge in extremist groups using the digital ecosystem to incite hatred, hostility and violence are a warning sign that these modes of communication may be having an adverse effect on democracy and that the boundary between fact and fiction is not as clear as we may like to think. The US presidential election campaign and the Brexit referendum (2016), the theories about COVID-19 (that have flooded the web since 2019), the terrorist attack against French teacher Samuel Paty (16 October 2020) all highlight these trends. When the majority of the world’s citizens are using online media as their main source of information, the proliferation of disinformation and the related threat of radicalism and extremism have led to a growing awareness of these issues at international- and European Union level. What can be done to tackle the situation? How should the democratic states with new forms of private power in the algorithmic society? Where should the line be drawn between freedom of expression and media pluralism on the one hand, and intrusion and censorship of dissenting opinions on the other? How should information be defended as a fundamental right? Is there a moral or ethical code when it comes to information? How can be created an environment that is conducive to inclusive, pluralistic public debate? How to equip citizens to develop a critical approach and to take informed decisions? How to balance innovation with the need to ensure transparency and fairness? Could we be witnessing a situation in which algorithms are “dissolving” democracy? Drawing on the archives of the international and European multilateral organisations (UN/UNESCO, Council of Europe, the Organisation for Security and Cooperation in Europe, the European Union) and several public and private stakeholders worldwide, this chapter proposes: a) to take stock of the issues and challenges raised by the proliferation of fake news, social media and algorithms, and their impact on freedom and democracy; b) to review the regulatory provisions implemented in this area at European and international level; and c) to identify future prospects. [less ▲]

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See detailHSM-based Key Management Solution for Ethereum Blockchain
Shbair, Wazen UL; Gavrilov, Eugene; State, Radu UL

in IEEE International Conference on Blockchain and Cryptocurrency, 3-6 May 2021 (2021, May 03)

The security of distributed applications backed by blockchain technology relies mainly on keeping the associated cryptographic keys (i.e. private keys) in well-protected storage. Since they are the unique ... [more ▼]

The security of distributed applications backed by blockchain technology relies mainly on keeping the associated cryptographic keys (i.e. private keys) in well-protected storage. Since they are the unique proof of ownership of the underlying digital assets. If the keys are stolen or lost, there is no way to recover the assets. The cold wallet is a good candidate for basic use cases, but it has a substantial challenge for more complex applications as it does not scale. Warm and hot wallets are more convenient options for blockchain-based solutions that aim to transact in a cloud environment. In this work, we focus on Hardware Security Module (HSM) based wallet. The HSM is the de-facto standard device designed to manage high-value cryptographic keys and to protect them against hacks. In this demonstration, we present an HSM-based working prototype that secures the entire life cycle of Ethereum public and private keys. [less ▲]

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See detailSense of Belonging: Predictors for Host Country Attachment Among Emigrants
Décieux, Jean; Murdock, Elke UL

in Erlinghagen, Marcel; Ette, Andreas; Schneider, Norbert (Eds.) et al The Global Lives of German Migrants: Consequences of International Migration Across the Life Course (2021)

German citizens usually leave their home country voluntarily and face fewer barriers, e.g. in terms of freedom of travel or labour market integration. However, when arriving in their host country, they ... [more ▼]

German citizens usually leave their home country voluntarily and face fewer barriers, e.g. in terms of freedom of travel or labour market integration. However, when arriving in their host country, they are confronted with the need to adapt to life in a new society. Analysing data from the German Emigration and Remigration Panel Study, we found that half of the emigrants developed a sense of belonging to their new host society. Moreover, we set out to examine this development of host country attachment. Guided by findings from acculturation and expatriate attachment research, we identified factors potentially contributing to host country attachment and tested these in a series of regression models. Permanence of the intended stay is the strongest predictor, and social integration also plays an important role. Host country language competence is also important for the identification processes. Regarding cultural distance, our findings suggest an inverted U-shaped relationship with certain cultural novelty facilitating the development of host country belonging. Moreover, the data point to a complex relationship between cultural characteristics of the target country and factors related to an emotional settlement. [less ▲]

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See detailYou should never be alone. Social work crossing borders and cultures in child protection and disability rights. Experiences from a current multinational research project.
Limbach-Reich, Arthur UL; Schulze-Kruedener, Joergen

Presentation (2021, May)

Social service providers in the Greater Region report that many children in need of special care and social assistance find themselves in cross-border situations. The legal regulations and practices for ... [more ▼]

Social service providers in the Greater Region report that many children in need of special care and social assistance find themselves in cross-border situations. The legal regulations and practices for the care of children and adolescents can vary considerably from country to country. This can cause delays, breaks or deterioration in the quality of support and sometimes irreversibly worsen the child's situation. Depending on the situation, diagnoses and access to social, medical-social or legal services can change considerably. The EURQUA project deals with cross-border child protection and disability rights within a multinational perspective. [less ▲]

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See detailUsing Domain-specific Corpora for Improved Handling of Ambiguity in Requirements
Ezzini, Saad UL; Abualhaija, Sallam UL; Arora, Chetan et al

in In Proceedings of the 43rd International Conference on Software Engineering (ICSE'21), Madrid 25-28 May 2021 (2021, May)

Ambiguity in natural-language requirements is a pervasive issue that has been studied by the requirements engineering community for more than two decades. A fully manual approach for addressing ambiguity ... [more ▼]

Ambiguity in natural-language requirements is a pervasive issue that has been studied by the requirements engineering community for more than two decades. A fully manual approach for addressing ambiguity in requirements is tedious and time-consuming, and may further overlook unacknowledged ambiguity – the situation where different stakeholders perceive a requirement as unambiguous but, in reality, interpret the requirement differently. In this paper, we propose an automated approach that uses natural language processing for handling ambiguity in requirements. Our approach is based on the automatic generation of a domain-specific corpus from Wikipedia. Integrating domain knowledge, as we show in our evaluation, leads to a significant positive improvement in the accuracy of ambiguity detection and interpretation. We scope our work to coordination ambiguity (CA) and prepositional-phrase attachment ambiguity (PAA) because of the prevalence of these types of ambiguity in natural-language requirements [1]. We evaluate our approach on 20 industrial requirements documents. These documents collectively contain more than 5000 requirements from seven distinct application domains. Over this dataset, our approach detects CA and PAA with an average precision of 80% and an average recall of 89% ( 90% for cases of unacknowledged ambiguity). The automatic interpretations that our approach yields have an average accuracy of 85%. Compared to baselines that use generic corpora, our approach, which uses domain-specific corpora, has 33% better accuracy in ambiguity detection and 16% better accuracy in interpretation. [less ▲]

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See detailThe Hormones of Dark Souls: The Dark Tetrad and Violent Gaming Effects on Aggression, Cortisol and Testosterone Levels
Wagener, Gary; Felten, Andrea; Melzer, André UL

Scientific Conference (2021, May)

Although playing violent video games may lead to detrimental effects on cognition, emotion and behavior, the role of hormones and its interplay with personality characteristics is not well understood. An ... [more ▼]

Although playing violent video games may lead to detrimental effects on cognition, emotion and behavior, the role of hormones and its interplay with personality characteristics is not well understood. An experimental study tested how playing a violent versus non-violent video game affects cortisol and testosterone levels, whether these hormonal changes increase implicit aggressive cognition, and whether Dark Tetrad personality traits moderate these effects. In an experimental design, 54 male participants played either a violent or a non-violent video game. Participants provided salivary samples at the beginning of the experiment (T1), right after 25 minutes of gameplay (T2), and 20 minutes after that (T3). There were no significant effects on implicit aggressive cognition. However, participants in the violent game condition had a significant decrease in cortisol levels (T1 to T2) and a significant negative trend in cortisol levels from T1 to T3. Participants with higher Machiavellianism scores in the violent condition had a stronger decrease in cortisol (T1 to T2). In contrast, participants with higher Machiavellianism scores in the non-violent condition had a higher increase in cortisol (T1 to T2). The present findings illustrate the complex interplay between personality, hormones, and game content, thus specifying current notions on violent game effects. [less ▲]

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See detailOffice Agents: Personal Office Vitality Sensors with Intent
Stamhuis, Sjoerd; Brombacher, Hans; Vos, Steven et al

Scientific Conference (2021, May)

In smart office buildings, almost every aspect of the environment can be assessed and adjusted by sensors. Yet employees rarely have access to the data collected to act upon it. It is also unclear what ... [more ▼]

In smart office buildings, almost every aspect of the environment can be assessed and adjusted by sensors. Yet employees rarely have access to the data collected to act upon it. It is also unclear what they would find meaningful to follow the recommendations on healthy work conditions and behavior, while productivity is the priority. The Office Agents are a set of artefacts placed on the employee’s desk, which capture data about the office environment. Air quality, sound level, light exposure, productivity, and physical activity level are measured to provide office workers with feedback on the ‘best’ working conditions. Using speculative design and Objects with Intent, the employee engages in a negotiation with the Office Agents based on the office ecosystem. Through this project and interactivity session, we open a debate on the use of sensors in office environments and the stakes around office vitality from the viewpoint of the employees. [less ▲]

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See detailAge of Information in IEEE 802.11p
Baiocchi, Andrea; Turcanu, Ion UL; Lyamin, Nikita et al

in 17th IFIP/IEEE International Symposium on Integrated Network Management (IM): ITAVT Workshop (2021, May)

Vehicle-to-Everything (V2X) communication is essential for facilitating connected and automated driving, where vehicles and other road traffic participants share data instantaneously and cooperate to ... [more ▼]

Vehicle-to-Everything (V2X) communication is essential for facilitating connected and automated driving, where vehicles and other road traffic participants share data instantaneously and cooperate to solve tricky traffic situations in milliseconds. This paper proposes two stochastic models for the V2X standard IEEE 802.11p to characterize amongst other things the Age of Information (AoI), a recently-proposed metric that measures the freshness of information. The first model is based on renewal process analysis of a tagged station with mean field approximation, while the second one adopts Markov chain approach with network level view. Analytical results show that IEEE 802.11p, given its adaptability to event-triggered and aperiodic messaging, supports advanced cooperative driving scenarios. [less ▲]

Detailed reference viewed: 110 (8 UL)