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See detail"Unless One Does the Research, It May Seem as Just a Useless Battery-Consuming App" - Field Notes on COVID-19 Contact Tracing Applications
Stojkovski, Borce UL; Abu-Salma, Ruba; Triquet, Karen et al

in Digital Threats: Research and Practice (2021)

Globally, countries have been developing contact tracing applications to control the spread of the Coronavirus (COVID-19) disease. In this work, we present the findings of eight focus groups we conducted ... [more ▼]

Globally, countries have been developing contact tracing applications to control the spread of the Coronavirus (COVID-19) disease. In this work, we present the findings of eight focus groups we conducted with participants living in France and Germany, to explore why they decided to adopt, or not adopt, a contact tracing application as well as understand how they perceived the benefits/drawbacks and the threat model of a contact tracing application. [less ▲]

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See detailThe unlikely Carnot efficiency
Verley, Gatien UL; Esposito, Massimiliano UL; Willaert, Tim et al

in Nature Communications (2014)

The efficiency of an heat engine is traditionally defined as the ratio of its average output work over its average input heat. Its highest possible value was discovered by Carnot in 1824 and is a ... [more ▼]

The efficiency of an heat engine is traditionally defined as the ratio of its average output work over its average input heat. Its highest possible value was discovered by Carnot in 1824 and is a cornerstone concept in thermodynamics. It led to the discovery of the second law and to the definition of the Kelvin temperature scale. Small-scale engines operate in the presence of highly fluctuating input and output energy fluxes. They are therefore much better characterized by fluctuating efficiencies. In this study, using the fluctuation theorem, we identify universal features of efficiency fluctuations. While the standard thermodynamic efficiency is, as expected, the most likely value, we find that the Carnot efficiency is, surprisingly, the least likely in the long time limit. Furthermore, the probability distribution for the efficiency assumes a universal scaling form when operating close-to-equilibrium. We illustrate our results analytically and numerically on two model systems. [less ▲]

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See detailUnlinkability of an Improved Key Agreement Protocol for EMV 2nd Gen Payments
Horne, Ross James UL; Mauw, Sjouke UL; Yurkov, Semen UL

Scientific Conference (2022, August 10)

To address known privacy problems with the EMV standard, EMVCo have proposed a Blinded Diffie-Hellman key establishment protocol, which is intended to be part of a future 2nd Gen EMV protocol. We point ... [more ▼]

To address known privacy problems with the EMV standard, EMVCo have proposed a Blinded Diffie-Hellman key establishment protocol, which is intended to be part of a future 2nd Gen EMV protocol. We point out that active attackers were not previously accounted for in the privacy requirements of this proposal protocol, and demonstrate that an active attacker can compromise unlinkability within a distance of 100cm. Here, we adopt a strong definition of unlinkability that does account for active attackers and propose an enhancement of the protocol proposed by EMVCo. We prove that our protocol does satisfy strong unlinkability, while preserving authentication. [less ▲]

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See detailUnlinkable Communication
Fusenig, Volker UL; Staab, Eugen UL; Sorger, Ulrich UL et al

in Privacy, Security and Trust, 2008. PST '08. Sixth Annual Conference on (2008)

In this paper we present a protocol for unlinkable communication, i.e. where an attacker cannot map the sender and receiver node of a communication. Existing anonymity protocols either do not guarantee ... [more ▼]

In this paper we present a protocol for unlinkable communication, i.e. where an attacker cannot map the sender and receiver node of a communication. Existing anonymity protocols either do not guarantee unlinkability (e.g. Tor and Mix networks), or produce huge overhead -- the dining cryptographers network causes quadratic number of messages. Our protocol needs only a linear number of messages while it still guarantees unlinkability. We introduce a measure of unlinkability and show that our protocol offers the highest possible degree of unlinkability. We show how to use the protocol in practice by adapting it to internet and ad hoc communication. [less ▲]

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See detailUnlinkable Updatable Databases and Oblivious Transfer with Access Control
Damodaran, Aditya Shyam Shankar UL; Rial, Alfredo UL

in 25th Australasian Conference on Information Security and Privacy (2020)

An oblivious transfer with access control protocol (OTAC) allows us to protect privacy of accesses to a database while enforcing access control policies. Existing OTAC have several shortcomings. First ... [more ▼]

An oblivious transfer with access control protocol (OTAC) allows us to protect privacy of accesses to a database while enforcing access control policies. Existing OTAC have several shortcomings. First, their design is not modular. Typically, to create an OTAC, an adaptive oblivious transfer protocol (OT) is extended ad-hoc. Consequently, the security of the OT is reanalyzed when proving security of the OTAC, and it is not possible to instantiate the OTAC with any secure OT. Second, existing OTAC do not allow for policy updates. Finally, in practical applications, many messages share the same policy. However, existing OTAC cannot take advantage of that to improve storage efficiency. We propose an UC-secure OTAC that addresses the aforementioned shortcomings. Our OTAC uses as building blocks the ideal functionalities for OT, for zero-knowledge (ZK) and for an \emph{unlinkable updatable database} ($\UUD$), which we define and construct. $\UUD$ is a protocol between an updater $\fuudUpdater$ and multiple readers $\fuudReader_k$. $\fuudUpdater$ sets up a database and updates it. $\fuudReader_k$ can read the database by computing UC ZK proofs of an entry in the database, without disclosing what entry is read. In our OTAC, $\UUD$ is used to store and read the policies. We construct an $\UUD$ based on subvector commitments (SVC). We extend the definition of SVC with update algorithms for commitments and openings, and we provide an UC ZK proof of a subvector. Our efficiency analysis shows that our $\UUD$ is practical. [less ▲]

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See detailUnlinkable Updatable Hiding Databases and Privacy-Preserving Loyalty Programs
Damodaran, Aditya Shyam Shankar UL; Rial, Alfredo UL

in Proceedings on Privacy Enhancing Technologies (2021, July), 2021(3), 95-121

Loyalty programs allow vendors to profile buyers based on their purchase histories, which can reveal privacy sensitive information. Existing privacy friendly loyalty programs force buyers to choose ... [more ▼]

Loyalty programs allow vendors to profile buyers based on their purchase histories, which can reveal privacy sensitive information. Existing privacy friendly loyalty programs force buyers to choose whether their purchases are linkable. Moreover, vendors receive more purchase data than required for the sake of profiling. We propose a privacy-preserving loyalty program where purchases are always unlinkable, yet a vendor can profile a buyer based on her purchase history, which remains hidden from the vendor. Our protocol is based on a new building block, an unlinkable updatable hiding database (HD), which we define and construct. HD allows the vendor to initialize and update databases stored by buyers that contain their purchase histories and their accumulated loyalty points. Updates are unlinkable and, at each update, the database is hidden from the vendor. Buyers can neither modify the database nor use old versions of it. Our construction for HD is practical for large databases. [less ▲]

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See detailUnlocking the Potential of Educationally Diverse Founding Teams for Firm Growth: The Moderating Role of New Venture Activities
Tryba, Anne UL; Patzelt, Holger; Breugst, Nicola

Scientific Conference (2018, April)

Detailed reference viewed: 94 (1 UL)
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See detailUnlocking web archives through metadata, seed lists and derived data
Clavert, Frédéric UL; Schafer, Valerie UL

Scientific Conference (2022, June 01)

This presentation addresses the use, re-use, access and dissemination of data related to web archives. Web archives (Brügger, 2018) have been for several years in a hybrid position regarding access ... [more ▼]

This presentation addresses the use, re-use, access and dissemination of data related to web archives. Web archives (Brügger, 2018) have been for several years in a hybrid position regarding access, depending on the institutions that were preserving them. While Internet Archive has made its collections available online since 2001 through the Wayback Machine (but with limited features for scholars willing to conduct a distant reading based on data, WARC files, etc.), most national libraries only allowed an onsite access due to authors rights restrictions (and in some cases the frame of legal deposits), while starting to provide interesting metadata for research projects willing to explore them. However, the situation is currently evolving in the frame of several research projects that allow to access a vast amount of (international) metadata and datasets. Taking two research projects in progress as case studies, WARCnet and AWAC2, this paper aims to present the move towards the use of metadata and derived data related to huge collections of web archives of the COVID crisis. WARCnet (Web ARChive studies network researching web domains and events) is a network whose activities (funded by the Independent Research Fund Denmark | Humanities (grant no 9055-00005B)) run in 2020-2023. The networking activities are guided by overarching research questions, one of them being “How transnational events developed on the European web?” (and notably the COVID crisis which is explored in WG2 (https://cc.au.dk/en/warcnet/working-groups)). AWAC2 (Analysing Web Archives of the COVID Crisis through the IIPC Novel Coronavirus dataset) is a project part of the Archives Unleashed Cohort Program, that supports and facilitates research engagement with web archives. It aims to explore a unique collection of web material (https://archive-it.org/collections/13529) related to the pandemic, with contributions from over 30 members of IIPC (International Internet Preservation Consortium) as well as public nominations from over 100 individuals/institutions. May it be in terms of access or tools, both projects are currently exploring new methodologies based on broad datasets (i.e. 5,3 TB for the IIPC collection related to the COVID crisis; 9.4 GB and 8,738,751 lines for the CSV related to plain text webpages). Starting with the WARCnet project, the presentation will explain how its WG2 gathered and accessed several national European datasets of COVID web archives, their specificities as well as their heterogeneity, the first analysis conducted through a datathon on January- February 2021 (Aasman et al. 2021) and the limits and assets of such access. Within the AWAC2 project (2021-2022) the access to the international IIPC COVID collection, through Archive-It and through the cohort program developed by the Archives Unleashed Team (Netpreserve, 2021; Ruest et al., 2021), is then a new opportunity to access data through mediated interfaces (ARCH) and to go further into them. Here again the presentation will demonstrate new opportunities and show a few examples of the analysis conducted by the team. Both examples aim to present the way web archiving institutions, libraries and researchers are developing new ways of accessing and exploring web archives, while also increasing their value(s) (Schafer and Winters, 2021). References Aasman, S., Bingham, N., Brügger, N., de Wild, K., Gebeil S. & Schafer V. (2021). Chicken and Egg: Reporting from a Datathon Exploring Datasets of the COVID- 19 Special Collections, WARCnet paper, Aarhus, https://cc.au.dk/fileadmin/dac/Projekter/WARCnet/Aasman_et_al_Chicken_and_Egg.pdf Brügger, N. (2018). The Archived Web. Doing History in the Digital Age. Cambridge, MA: The MIT Press. IIPC (2021), A Retrospective with the Archives Unleashed Project, netpreserve blog, https://netpreserveblog.wordpress.com/2021/04/01/a-retrospective-with-the-archives-unleashed-project/ Ruest, N., Fritz, S., Deschamps, R. Lin, J. & Milligan, I. (2021) From archive to analysis: accessing web archives at scale through a cloud-based interface. International Journal of Digital Humanities, https://paperity.org/p/260049927/from-archive-to-analysis-accessing-web-archives-at-scale-through-a-cloud-based-interface Schafer V. & Winters J. (2021). The values of web archives, International Journal of Digital Humanities, 1-10, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8190571/ [less ▲]

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See detailUnmanned aerial vehicles UAVs attitude, height, motion estimation and control using visual systems
Mondragon, Ivan F.; Olivares Mendez, Miguel Angel UL; Campoy, Pascual et al

in AUTONOMOUS ROBOTS (2010), 29(1), 17-34

This paper presents an implementation of an aircraft pose and motion estimator using visual systems as the principal sensor for controlling an Unmanned Aerial Vehicle (UAV) or as a redundant system for an ... [more ▼]

This paper presents an implementation of an aircraft pose and motion estimator using visual systems as the principal sensor for controlling an Unmanned Aerial Vehicle (UAV) or as a redundant system for an Inertial Measure Unit (IMU) and gyros sensors. First, we explore the applications of the unified theory for central catadioptric cameras for attitude and heading estimation, explaining how the skyline is projected on the catadioptric image and how it is segmented and used to calculate the UAV's attitude. Then we use appearance images to obtain a visual compass, and we calculate the relative rotation and heading of the aerial vehicle. Additionally, we show the use of a stereo system to calculate the aircraft height and to measure the UAV's motion. Finally, we present a visual tracking system based on Fuzzy controllers working in both a UAV and a camera pan and tilt platform. Every part is tested using the UAV COLIBRI platform to validate the different approaches, which include comparison of the estimated data with the inertial values measured onboard the helicopter platform and the validation of the tracking schemes on real flights. [less ▲]

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See detailUnmet Needs of People With Parkinson's Disease and Their Caregivers During COVID-19-Related Confinement: An Explorative Secondary Data Analysis.
Hanff, Anne-Marie UL; Pauly, Claire UL; Pauly, Laure UL et al

in Frontiers in neurology (2020), 11

Self-perceived unmet needs in people with typical and atypical parkinsonism (PwP) and their caregivers, support network, personalized ways to address self-perceived unmet needs during confinement, as well ... [more ▼]

Self-perceived unmet needs in people with typical and atypical parkinsonism (PwP) and their caregivers, support network, personalized ways to address self-perceived unmet needs during confinement, as well as the prevalence of self-reported COVID-19 related symptoms, confirmed SARS-CoV-2 infection, and self-reported COVID-19 related hospitalization in Luxembourg and the Greater Region were assessed. From 18th March to 10th April 2020, 679 PwP were contacted by phone. Data was collected in the form of a semi-structured interview. The thematic synthesis identified 25 themes where PwP need to be supported in order to cope with consequences of the pandemic, and to adapt their daily and health-related activities. The present work highlights that in the context of personalized medicine, depending on the individual needs of support of the patient the identified self-perceived unmet needs were addressed in various ways ranging from one-directed information over interaction up to proactive counseling and monitoring. Family and health professionals, but also other support systems were taking care of the unmet needs of PwP (e.g., shopping, picking-up medication, etc.) during the pandemic. 7/606 PwP (1.15%) reported COVID-19 related symptoms, 4/606 (0.66%) underwent a rRT-PCR-based diagnostic test and 2/606 (0.33%) were confirmed as SARS-CoV-2 positive. None of these PwP reported being hospitalized due to COVID-19. Our results will allow health professionals to expand their services in a meaningful way i.e., personalize their support in the identified themes and thus improve the healthcare of PwP in times of crisis. [less ▲]

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See detailThe Unnoticed Corssroads of Russian-Luxembourgish History
Ganschow, Inna UL

Presentation (2018, October 02)

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See detailUnordentliche Verhältnisse. Familie als Argument in Suppliken und Bittbriefen
Gerstenmayer, Christina; Tatarinov, Juliane UL

in Arbeitskreis Repräsentation des SFB 600 (Ed.) Die 'andere' Familie. Repräsentationskritische Analysen von der Frühen Neuzeit bis zur Gegenwart (2013)

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See detailUnpacking Collaboration in Digital History Projects
Kemman, Max UL

Scientific Conference (2017)

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See detailUnpacking Luxembourg Governance through Sustainable Development Policy
Carr, Constance UL

Presentation (2012, February)

Luxembourg has an almost two century history of cross-border political economic interdependence, whether that was through the Zollverein and expansion of the railroads during the 19th century, the steel ... [more ▼]

Luxembourg has an almost two century history of cross-border political economic interdependence, whether that was through the Zollverein and expansion of the railroads during the 19th century, the steel industry that remains largely intact, or the banking and related services sector that dominates the Luxembourgish economy today. Luxembourg has also cultivated deep cross-border connections through its role in the European Union, and establishment of itself as one of the centres for important EU institutions. These structures overlay its otherwise feudal and agricultural legacy. This has led to a political structure that some complain is non-transparent and undemocratic, but that others notice is horizontal, direct, and entails shorter power distances. It has also led to a demos whose membership is defined by the usual legal parameters of nationhood, but at the same time is inter-reliant on cross-border competencies and cycles of de- and reinvestment, as well as personal relations. These paths of governance are easily traced through the mobility of Luxembourg’s sustainable development policies. In so doing, it can be seen that the uncertain governance structure that operates simultaneously multi-scalar, cross-national, and informal, which poses many obstructions to the implementation of environmental policy and renders the normative of sustainable development, that permeates all levels of planning in Luxembourg, postpolitical. [less ▲]

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See detailUnpacking Tourism in the Cold War: International Tourism and Commercialism in Socialist Romania, 1960s-1980s
Stefan, Oana Adelina UL

in Contemporary European History (in press)

The role of market oriented tourist policies in the planned economies of socialist Eastern Europe has been long overlooked. This article examines how the socialist regime in Romania moved from sheer ... [more ▼]

The role of market oriented tourist policies in the planned economies of socialist Eastern Europe has been long overlooked. This article examines how the socialist regime in Romania moved from sheer ideological rhetoric to commercialism and market-driven strategies when promoting Romania as a tourist destination in the ‘West’ between the 1960s and the 1980s. It argues that there was a continual shifting between using tourism as an ideological tool and a certain pragmatism that was needed to turn Romania into a desirable tourist destination. [less ▲]

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See detailUnpolitisches Mega-Event oder neue soziale Bewegung?
Sabra, Martina; Schröder, Christian UL

Diverse speeches and writings (2015)

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See detailUnramifiedness of Galois representations attached to weight one Hilbert modular eigenforms mod p
Wiese, Gabor UL

Scientific Conference (2015, November 13)

The talk will summarise the main ideas underlying the recent joint work with Mladen Dimitrov, proving that the existence of Hecke operators T_P, for P dividing p, implies that the Galois representation ... [more ▼]

The talk will summarise the main ideas underlying the recent joint work with Mladen Dimitrov, proving that the existence of Hecke operators T_P, for P dividing p, implies that the Galois representation attached to a mod p Hilbert modular eigenform of parallel weight one and prime-to-p level is unramified above p. This applies, in particular, to non-liftable mod p eigenforms, and can be seen as a refinement of the weight aspect in generalisations of Serre's Modularity Conjecture to Hilbert modular forms. [less ▲]

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See detailUnramifiedness of Galois representations attached to weight one Hilbert modular eigenforms mod p
Dimitrov, Mladen; Wiese, Gabor UL

in Journal of the Institute of Mathematics of Jussieu (2020), 19(2), 281-306

The main result of this article states that the Galois representation attached to a Hilbert modular eigenform defined over F_p^bar of parallel weight 1 and level prime to p is unramified above p. This ... [more ▼]

The main result of this article states that the Galois representation attached to a Hilbert modular eigenform defined over F_p^bar of parallel weight 1 and level prime to p is unramified above p. This includes the important case of eigenforms that do not lift to Hilbert modular forms in characteristic 0 of parallel weight 1. The proof is based on the observation that parallel weight 1 forms in characteristic p embed into the ordinary part of parallel weight p forms in two different ways per prime dividing p, namely via `partial' Frobenius operators. MSC: 11F80 (primary); 11F41, 11F33 Keywords: Hilbert modular forms modulo p, weight one, Galois representations [less ▲]

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See detailUnramifiedness of weight one Hilbert Hecke algebras
Deo, Shaunak; Dimitrov, Mladen; Wiese, Gabor UL

E-print/Working paper (2019)

We prove that the Galois pseudo-representation valued in the mod p^n parallel weight 1 Hecke algebra for GL(2) over a totally real number field F is unramified at a place above p if p-1 does not divide ... [more ▼]

We prove that the Galois pseudo-representation valued in the mod p^n parallel weight 1 Hecke algebra for GL(2) over a totally real number field F is unramified at a place above p if p-1 does not divide the ramification index at that place. A novel geometric ingredient is the construction and study, in the case when p ramifies in F, of generalised Theta-operators using Reduzzi-Xiao's generalised Hasse invariants, including especially an injectivity criterion in terms of minimal weights. [less ▲]

Detailed reference viewed: 69 (5 UL)