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See detailA performance evaluation of weight-constrained conditioned portfolio optimization
Schiltz, Jang UL; Boissaux, Marc UL

Scientific Conference (2019, December 20)

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See detailHome literacy environment and family language policy of immigrant families in Luxembourg
Aleksic, Gabrijela UL; Bebic, Dzoen Dominique UL

Scientific Conference (2019, December 18)

Early literacy skills are critical for children’s later academic achievement. A wealth of research showed that children’s home languages should not be abandoned, as they are crucial for promoting dynamic ... [more ▼]

Early literacy skills are critical for children’s later academic achievement. A wealth of research showed that children’s home languages should not be abandoned, as they are crucial for promoting dynamic multilingualism, assuring cross-linguistic transfer and developing identities. To explore home literacy environment and family language policy of language minority preschool children in Luxembourg, we obtained 603 parent questionnaires, tested 226 children age 4 to 6 in their home languages and Luxembourgish, and interviewed 31 families. The results from the questionnaires showed that the home resources and parent involvement influenced children’s language awareness and their print knowledge irrespective of parent’s education and their wealth. Concerning children’s competences in Luxembourgish, children with positive attitudes towards their school did better than their peers in other schools. In the interviews, parents explained that maintaining home language is important for keeping connections with family, friends and their culture. This is the language parents feel emotionally connected to and the easiest to transmit to their children. Language maintenance is mostly achieved through conversations, movies, games and books in the home languages, children’s attendance of language schools on weekends, celebrations of traditions as well as holidays in the native country of the parents. The home language is, however, not something parents enforce too strictly, as they mostly correct the children’s linguistic mistakes by simple repetition. It is often with great pride that parents report their children having an excellent proficiency in their home language. Finally, through our professional development training in translanguaging we are helping teachers to integrate children’s different home languages and cultures into the classroom and strengthen the home-school collaboration in order to support children’s well-being, learning and identities. [less ▲]

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See detailFrom home to early childhood education: beliefs, language ideologies and OPOL
Kirsch, Claudine UL

Scientific Conference (2019, December 18)

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See detailYoung emergent multilingual children's agency in learning new language in trilingual Luxembourg
Mortini, Simone UL

Scientific Conference (2019, December 14)

Studies on translanguaging suggest that opportunities to use languages flexibly in the classroom may give children some agency over their language use and facilitate their language learning (García ... [more ▼]

Studies on translanguaging suggest that opportunities to use languages flexibly in the classroom may give children some agency over their language use and facilitate their language learning (García & Kleifgen, 2010). In the emerging field of preschool bilingual education, scholars investigate the concept of child agency in relation to the learning of multiple languages (Schwartz, 2018). Children were shown to actively and creatively contribute to their language learning through choosing to interact in a particular language. Studies on young children’s translanguaging and agency nevertheless remain scarce, especially in multilingual contexts involving more than two languages (Schwartz et al., forthcoming). The present study focuses on eight children’s agentive behaviour in multilingual practices in two formal and two non-formal early childhood education institutions participating in a larger longitudinal research project on the development of multilingual pedagogies in trilingual Luxembourg. I drew on multidimensional qualitative research methods, including 65 days of participant observations, fieldnotes, video-recordings and semi-structured interviews with the practitioners. The findings show that all the children made use of various non-linguistic strategies and at least four named languages and translanguaged for various purposes (e.g. demonstrating knowledge, meaning making). Moreover, they showed two types of agentive behaviour: ‘participatory agency’ (e.g. adapting learning to practitioners’ requirements) and ‘controlling agency’ (e.g. influencing or changing peers’ or practitioners’ language use). The findings should deepen our understanding of the interplay between agency and translanguaging. García, O., & Kleifgen, J. (2010). Educating Emergent Bilinguals. Policies, Programs and Practices for English Language Learners. New York: Teachers College Press. Schwartz, M. (2018). Preschool Bilingual Education: Agency in Interactions between Children, Teachers, and Parents. Dordrecht: Springer. Schwartz, M., Kirsch, C., & Mortini, S. (forthcoming). Young children’s language-based agency in multilingual contexts in Luxembourg and Israel. (Applied Linguistic Review). Manuscript accepted for publication. [less ▲]

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See detailLocalization Performance of 1-Bit Passive Radars in NB-IoT Applications
Sedighi, Saeid UL; Mishra, Kumar Vijay; Shankar, Bhavani UL et al

in Sedighi, Saeid; Mishra, Kumar Vijay; Shankar, Bhavani (Eds.) et al Localization Performance of 1-Bit Passive Radars in NB-IoT Applications (2019, December 14)

Location-based services form an important use-case in emerging narrowband Internet-of-Things (NB-IoT) networks. Critical to this offering is an accurate estimation of the location without overlaying the ... [more ▼]

Location-based services form an important use-case in emerging narrowband Internet-of-Things (NB-IoT) networks. Critical to this offering is an accurate estimation of the location without overlaying the network with additional active sensors. The massive number of devices, low power requirement, and low bandwidths restrict the sampling rates of NB-IoT receivers. In this paper, we propose a novel low-complexity approach for NB-IoT target delay estimation in cases where one-bit analog-to-digital-converters (ADCs) are employed to sample the received radar signal instead of high-resolution ADCs. This problem has potential applications in the design of inexpensive NB-IoT radar and sensing devices. We formulate the target estimation as a multivariate fractional optimization problem and solve it via Lasserre's semi-definite program relaxation. Numerical experiments suggest feasibility of the proposed approach yielding high localization accuracy with a very low number of 1-bit samples. [less ▲]

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See detailA professional development course in translanguaging: Teachers’ stance, design, and shifts
Aleksic, Gabrijela UL

Scientific Conference (2019, December 14)

The school population in Luxembourg is highly socially, culturally, and linguistically diverse. The new law in 2017 has declared multilingual early education mandatory, with the focus not only on the ... [more ▼]

The school population in Luxembourg is highly socially, culturally, and linguistically diverse. The new law in 2017 has declared multilingual early education mandatory, with the focus not only on the development of Luxemburgish, but also familiarizing children with French and valuing their home languages. Thus, our project aims to: (1) offer a professional development (PD) course in translanguaging to preschool teachers, (2) involve children’s families to reinforce home-school collaboration, and (3) foster children’s cognitive, linguistic, and socio-emotional engagement in the classroom. With teachers, we use focus groups, questionnaires, and language portraits, with parents, we employ questionnaires and interviews, and with children, a test in early literacy and numeracy in school and home language and video observations. Translanguaging is the use of a full linguistic repertoire to make meaning (Otheguy, García, & Reid, 2015). Translanguaging pedagogy is the main topic of our 22 hour PD course (June – December 2019) for 40 teachers. In the focus groups, the teachers shared their negative translanguaging stance towards the use of children’s home languages in the classroom, convinced that it hindered the development of Luxembourgish. Teachers, however, in some instances incorporated a translanguaging design (e.g. multilingual stories, morning greetings) and translanguaging shift (e.g. translations by older children). The project addresses these negative translanguaging stances through practical activities and a close collaboration with parents, children and organisational stakeholders. The preliminary results from parent questionnaires and tests with children will provide a bigger picture of the effect of translanguaging pedagogy from our PD course on all the actors involved. References Otheguy, R., García, O., & Reid, W. (2015). Clarifying translanguaging and deconstructing named languages: A perspective from linguistics. Applied Linguistic Review, 6(3), 281–307. [less ▲]

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See detailConsolidating Observation of Land and Sea Level Changes around South Georgia Island
Teferle, Felix Norman UL; Hunegnaw, Addisu UL; Hibbert, Angela et al

Poster (2019, December 13)

With its mid-ocean location in the Southern Atlantic Ocean South Georgia Island is in a key position for the oceanic and geodetic global monitoring networks. Since 2013 the tide gauge at King Edward Point ... [more ▼]

With its mid-ocean location in the Southern Atlantic Ocean South Georgia Island is in a key position for the oceanic and geodetic global monitoring networks. Since 2013 the tide gauge at King Edward Point (KEP) with GLOSS ID 187 has been monitored using a GNSS station nearby on Brown Mountain. By accurately geo-referencing the tide gauge and monitoring any vertical land movements, a continuous record of its datum within the Permanent Service for Mean Sea Level (PSMSL) can be established, which in turn makes the recorded and averaged sea levels useful for long-term studies and satellite altimetry calibrations. In 2014 another GNSS station was installed at KEP after local subsidence was sus-pected and later on three additional GNSS stations came to service at the periphery of the main island, making it possible to monitor uplift/subsidence wider afield. Further-more, together with four precise levelling campaigns of the KEP benchmark network in 2013, 2014 and two in 2017, it has also been possible to investigate the very local character of the vertical motions near KEP, i.e. the stability of the jetty upon which the tide gauge is mounted. In this study, we will present the results from the GNSS and precise levelling meas-urements, and will discuss their impact on the sea level record from the KEP tide gauge and nearby satellite altimetry sea surface heights. This study comes at a timely manner as during the Austral Summer 2019/2020 the jetty will be stabilized and en-larged, and consequently the current tide gauge will be replaced by a new one. Our measurements show that uplift is observed all over South Georgia Island while the ar-ea at KEP and particularly the jetty with tide gauge are subsiding relative to the rest of the island. In contrast, results for the tide gauge record show a lower magnitude of ob-served sea level rise than expected from nearby satellite altimetry. We will revisit all geodetic and oceanic observations in an attempt to improve the agreement between these measurements to summarize the status before the work at the jetty begins. [less ▲]

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See detailUsing the Vertical Land Movement estimates from the IGS TIGA combined solution to derive Global Mean Sea Level changes
Bogusz, Janusz; Hunegnaw, Addisu UL; Teferle, Felix Norman UL et al

Scientific Conference (2019, December 13)

Global mean sea level (GMSL) is now widely recognized to have risen between 1 to 2 mm/yr depending on location since the 20th century. Prior to the satellite altimetry era, GMSL was primarily estimated ... [more ▼]

Global mean sea level (GMSL) is now widely recognized to have risen between 1 to 2 mm/yr depending on location since the 20th century. Prior to the satellite altimetry era, GMSL was primarily estimated from a set of secular tide gauge records relative to coastal benchmarks. Recent measurements of GPS (Global Positioning System) have been demonstrated as a useful tool of a direct estimate of Vertical Land Motion (VLM) induced by both long and short-term geophysical and human-induced processes in a geocentric reference frame. This presentation will provide the results of a combination performed using the CATREF software of three independent GPS daily solutions provided by British Isles continuous GNSS Facility – University of Luxembourg consortium (BLT), German Research Centre for Geosciences (GFZ) and University of La Rochelle (ULR) under the auspices of the Tide Gauge Benchmark Monitoring (TIGA) Working Group (WG), that results in a spatially comprehensive map of VLM near or close to tide gauge benchmarks. The combination was performed in accordance with the second re-processing campaign (repro2) of the IGS (International GNSS Service). Long coastal tide gauge records from the archives maintained at the Permanent Service for Mean Sea Level (PSMSL) were extracted for relative sea level estimates. To cross-compare the sea level rates over the years, we employed observations between 1900-2016. Then, the time series were cut and analyzed separately, ceteris paribus, for the period 1960-2016. This analysis was aimed at a cross-comparison of relative sea level trends and their changes over the years. The stochastic part of the tide gauge records was analyzed with Maximum Likelihood Estimation (MLE) and assumed several different combinations of noise models with the Bayesian Information Criterion (BIC) providing a means to identify the preferred one. The relative sea level estimates were corrected by the inverted barometric effect to the tide-gauge records using data from the 20th century Reanalysis project version V2C, the effect of wind stress on the surface of the ocean in both, zonal and meridional components, as well as Pacific Decadal Oscillation (PDO) and the North Pacific Gyre Oscillation (NPGO) influencing Pacific tide gauge records. The GPS-based velocities were corrected by Glacial Isostatic Adjustment (GIA) effect using ICE-6G(VM5a) model with associated geoid rate and post seismic decays using ITRF2014 estimates. Also, environmental loading models were employed to account for present-day elastic loading in VLM. The Mean Sea Level (MSL) trends from tide gauges and VLM-corrected MSL trends using GIA model (TG+GIA) and the TIGA combination (TG+TIGA) were determined. Our final reconstruction of GMSL based on the MSL records from 1900 to 2016 where the VLM uncertainty is smaller than 0.7 mm/yr indicate a long-term trend of 1.75 +/- 0.2 mm/yr and is in good agreement with several similar determinations. [less ▲]

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See detailWhy is the Market Skewness-Return Relationship Negative?
Lehnert, Thorsten UL

Scientific Conference (2019, December 13)

The observed negative relationship between market skewness and excess return or the negative price of market skewness risk in the cross-section of stock returns is somewhat counterintuitive when we ... [more ▼]

The observed negative relationship between market skewness and excess return or the negative price of market skewness risk in the cross-section of stock returns is somewhat counterintuitive when we consider the usual interpretation of e.g. option-implied skewness as an indicator of jump risk or downside risk. One possible explanation for this inconsistency is that there are factors affecting option-implied market skewness other than jump risk in the stock market. In this paper, I find that price pressure associated with “crowded trades” of mutual funds is an important endogenous factor. Given that retail investors are prone to herding, the directional trading of mutual funds is correlated, and their collective actions can generate short-term price pressure on aggregate stock prices. Short sellers systematically exploit these patterns not only in the equity lending market, but also in the options market. In line with this economic channel, I find that firstly, the significant negative relationship between market skewness and returns becomes insignificant, once I control for price pressure. Secondly, the negative relationship is only present for the “bad” downside component of risk-neutral skewness, associated with out-of-the-money put options. For the “good” upside component of risk-neutral skewness, associated with out-of-the-money call options, the relationship is always positive. Thirdly, price pressure affects the skewness-return relationship, which can be clearly distinguished from the impact of flows on the volatility-return relationship in terms of the leverage effect. [less ▲]

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See detailConventional EO Satellites vs. CubeSats; FDL - AI flood detection onboard a Nano Satellite
Backes, Dietmar UL; Schumann, Guy; Teferle, Felix Norman UL

Scientific Conference (2019, December 11)

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See detailTracking hurricanes Harvey and Irma using GPS tropospheric products
Ejigu, Yohannes Getachew; Teferle, Felix Norman UL; Hunegnaw, Addisu UL et al

Poster (2019, December 10)

The 2017 Hurricanes season was one of the most powerful severe weather events producing catastrophic socio-economic and environmental effects on the east coast of the United States. Therefore, tracking ... [more ▼]

The 2017 Hurricanes season was one of the most powerful severe weather events producing catastrophic socio-economic and environmental effects on the east coast of the United States. Therefore, tracking their path accurately is extremely useful. Today Global Navigation Satellite Systems (GNSS) tropospheric products, such as Zenith Wet Delays (ZWD), and Integrated Water Vapor (IWV) are used as complementary data sets in Numerical Weather Prediction (NWP) models. In this study, we employed GPS-derived IWV and horizontal tropospheric gradient information to monitor and investigate the complicated characteristics of hurricane events in their spatial and temporal distribution using a dense ground network of GPS stations. Our results show that a surge in GPS-derived IWV occurred several hours prior to the manifestation of the major hurricanes Harvey and Irma. We used the derived GPS-derived IWV information as input to spaghetti lines weather models, allowing us to predict the paths of Harvey and Irma hurricanes. As such, a parameter directly estimated from GPS can provide an additional resource for improving the monitoring of hurricane paths [less ▲]

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See detailAbsolute Gravity and Uplift in the Yellowstone Caldera
van Dam, Tonie UL; Francis, Olivier UL

Scientific Conference (2019, December 10)

GPS time-series of uplift show that points in and around the caldera have gone through cycles of uplift, followed by subsidence since observations began about three decades ago. A dramatic increase in the ... [more ▼]

GPS time-series of uplift show that points in and around the caldera have gone through cycles of uplift, followed by subsidence since observations began about three decades ago. A dramatic increase in the uplift rate started in 2004 at the GPS station LKWY near Yellowstone Lake and Old Faithful, OFWY. Since 2010, the sites have subsided, began uplifting again in 2014 coincidentally after a M 4.8 earthquake near the Norris Geyser Basin, and then started subsiding again in 2016. The cause of the episodic uplift and subsidence and the spatial pattern of the surface displacement are not yet well understood. The 2003-2009 episode of rapid uplift is believed to result from deep source magma intrusion simultaneous with depressurization of the hydrothermal systems beneath the Norris Geyser Basin. But whether it is caused by the intrusion of magma from a distant reservoir, or by the expulsion and localized trapping of pressurized water and gas from rock that is already in-place, is not known. We have taken observations of absolute gravity at LKWY and OFWY almost annually since 2009. In this presentation, we compare gravity and uplift and provide some insight into the mechanism driving the uplift/subsidence cycles. [less ▲]

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See detailHydrogeological effects on terrestrial gravity measurements
Van Camp, Michel; de Viron, Olivier; Dassargues, Alain et al

Scientific Conference (2019, December 10)

For the 20 last years, terrestrial and satellite gravity measurements have reached such a precision that they allow for identification of the signatures from water storage fluctuations. In particular ... [more ▼]

For the 20 last years, terrestrial and satellite gravity measurements have reached such a precision that they allow for identification of the signatures from water storage fluctuations. In particular, hydrogeological effects induce significant time-correlated signature in the gravity time series. Gravity response to rainfall is a complex function of the local geologic and climatic conditions, e.g., rock porosity, vegetation, evaporation, and runoff rates. The gravity signal combines contributions from many geophysical processes, source separation being a major challenge. At the local scale and short-term, the associated gravimetric signatures often exceed the tectonic and GIA effects, and monitoring gravity changes is a source of information on local groundwater mass balance, and contributes to model calibrations. Some aquifer main characteristics can then be inferred by combining continuous gravity, geophysical and hydrogeological measurements. In Membach, Belgium, a superconducting gravimeter has monitored gravity continuously for more than 24 years. This long time series, together with 300 repeated absolute gravity measurements and environmental monitoring, has provided valuable information on the instrumental, metrological, hydrogeological and geophysical points of view. This has allowed separating the signal sources and monitoring partial saturation dynamics in the unsaturated zone, convective precipitation and evapotranspiration at a scale of up to 1 km², for signals smaller than 1 nm/s², equivalent to 2.5 mm of water. Based on this experience, another superconducting gravimeter was installed in 2014 in the karst zone of Rochefort, Belgium. In a karst area, where the vadose zone is usually thicker than in other contexts, combining gravity measurements at the surface and inside accessible caves is a way to separate the contribution from the unsaturated zone lying between the two instruments, from the saturated zone underneath the cave, and the common mode effects from the atmosphere or other regional processes. Those experiments contribute to the assessment of the terrestrial hydrological cycle, which is a major challenge of the geosciences associated with key societal issues: availability of freshwater, mitigation of flood hazards, or measurement of evapotranspiration. [less ▲]

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See detailCarrier Aggregation in Multi-Beam High Throughput Satellite Systems
Kibria, Mirza UL; Lagunas, Eva UL; Maturo, Nicola UL et al

in Carrier Aggregation in Multi-Beam High Throughput Satellite Systems (2019, December 10)

Carrier Aggregation (CA) is an integral part of current terrestrial networks. Its ability to enhance the peak data rate, to efficiently utilize the limited available spectrum resources and to satisfy the ... [more ▼]

Carrier Aggregation (CA) is an integral part of current terrestrial networks. Its ability to enhance the peak data rate, to efficiently utilize the limited available spectrum resources and to satisfy the demand for data-hungry applications has drawn large attention from different wireless network communities. Given the benefits of CA in the terrestrial wireless environment, it is of great interest to analyze and evaluate the potential impact of CA in the satellite domain. In this paper, we study CA in multi-beam high throughput satellite systems. We consider both inter-transponder and intra-transponder CA at the satellite payload level of the communication stack, and we address the problem of carrier-user assignment assuming that multiple users can be multiplexed in each carrier. The transmission parameters of different carriers are generated considering the transmission characteristics of carriers in different transponders. In particular, we propose a flexible carrier allocation approach for a CA enabled multi-beam satellite system targeting a proportionally fair user demand satisfaction. Simulation results and analysis shed some light on this rather unexplored scenario and demonstrate the feasibility of the CA in satellite communication systems. [less ▲]

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See detailJoint Scheduling and Precoding for Frame-Based Multigroup Multicasting in Satellite Communications
Bandi, Ashok UL; Shankar, Bhavani UL; Chatzinotas, Symeon UL et al

in Bandi, Ashok; Shankar, Bhavani; Chatzinotas, Symeon (Eds.) et al Joint Scheduling and Precoding for Frame-Based Multigroup Multicasting in Satellite Communications (2019, December 09)

Recent satellite standards enforce the coding of multiple users’ data in a frame. This transmission strategy mimics the well-known physical layer multigroup multicasting (MGMC). However, typical beam ... [more ▼]

Recent satellite standards enforce the coding of multiple users’ data in a frame. This transmission strategy mimics the well-known physical layer multigroup multicasting (MGMC). However, typical beam coverage with a large number of users and limited frame length lead to the scheduling of only a few users. Moreover, in emerging aggressive frequency reuse systems, scheduling is coupled with precoding. This is addressed in this work, through the joint design of scheduling and precoding for frame-based MGMC satellite systems. This aim is formulated as the maximization of the sum-rate under per beam power constraint and minimum SINR requirement of scheduled users. Further, a framework is proposed to transform the non-smooth SR objective with integer scheduling and nonconvex SINR constraints as a difference-of-convex problem that facilitates the joint update of scheduling and precoding. Therein, an efficient convex-concave procedure based algorithm is proposed. Finally, the gains (up to 50%) obtained by the jointed design over state-of-the-art methods is shown through Monte-Carlo simulations. [less ▲]

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See detailParameter identification problem in bimaterial human skin and sensitivity analysis : Uncertainties in biomechanics of skin
Sutula, Danas; Elouneg, Aflah; Sensale, Marco UL et al

Scientific Conference (2019, December 09)

The proposed paper concerns the prediction of the numerical response of a biomechanical structure submitted to an unknown external loading state. The methodology is based on homogeneous and then ... [more ▼]

The proposed paper concerns the prediction of the numerical response of a biomechanical structure submitted to an unknown external loading state. The methodology is based on homogeneous and then heterogeneous structures such as healthy or pathological cutaneous tissues that can be mechanically tested in vivo under a patchy knowledge of boundary conditions. Experimental data corresponding to the extension of a piece of skin located between two pads with displacement enslavement, represent input data to the numerical model. Data are reaction force on one pad and displacement field between the two pads and all around. The numerical model consists of a representation of the bi-material domain geometry with neo-hookean behaviors. The boundary conditions and loadings of the experimental extension test are imposed. The materials parameters have been identified by inverse method starting from a constrained cost function minimizing the difference between the calculated displacements field and experimental displacements field obtained by digital image correlation and taking into account the reaction force as a constraint. An analysis of the model sensitivity to material parameters is presented. [less ▲]

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See detailMechanical parameters identification of keloid and surrounding healthy skin using Digital Image Correlation measurements in vivo
Elouneg, Aflah; Sutula, Danas; Sensale, Marco UL et al

Scientific Conference (2019, December 09)

The human skin behaves as an elastic membrane initially prestressed but not uniformly. The presence of anatomical sites favorable to the appearance of some tumors, a keloid in our case, while other sites ... [more ▼]

The human skin behaves as an elastic membrane initially prestressed but not uniformly. The presence of anatomical sites favorable to the appearance of some tumors, a keloid in our case, while other sites never develop them attests to the importance of the mechanical environment of the tissue. Thus, a mechanical characterization of the tumored skin is necessary to understand the keloid expansion from a mechanical point of view. Our case study consists in modeling a bi-material structure composed of a keloid skin surrounded by healthy skin located on upper left arm of a young female. From the experimental measurements in vivo, by combining force sensor, displacement sensor and Digital Image Correlation techniques, we perform a mechanical analysis to characterize the mechanical stress fields over the entire area and on the interface ‘healthy skin/keloid skin’. Since the mechanical behavior of the tumorous skin is unknown, many physical models can be implemented and assessed very easily inside the specific digital software to fit with the real data. Once a set of mechanical parameters for both the healthy skin and the keloid skin are identified, the stress fields around the keloid are calculated. Next steps consist in determining matching preferential directions in order to define as precisely as possible the specifications of a device for preventing the growth of keloids. [less ▲]

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See detailPsychiatric knowledge dissimination at international conferences (1860-1914): 'those who have the interest of science at heart, don't distinguish between nationalities'
Andersen, Eva UL

Scientific Conference (2019, December 06)

The amount of international conferences that were organised over the nineteenth century increased rapidly, and formed an ideal environment for discussions amongst peers and establishing knowledge ... [more ▼]

The amount of international conferences that were organised over the nineteenth century increased rapidly, and formed an ideal environment for discussions amongst peers and establishing knowledge transfers. Medical and psychiatric conferences were no exception. However, a study into psychiatric conferences on a larger scale has not yet been conducted. Adopting a transnational perspective is essential, and while this approach is gaining more attention from historians more generally, it is only slowly reaching the history of psychiatry. To gain insights into the (inter)national knowledge dissemination that happened within psychiatry, we will examine different organisational aspects such as the locations where conferences were held, its organisation and the subjects and questions that were included in the conference program, as well as studying the mutual connections between congresses and the connections between the participants. This will help to discover the key players and whether it was well-known psychiatrists that were most involved in these international conferences. These interwoven sub-questions will help to establish in how far an international community existed within psychiatry and thus if such international congresses were an epicentre of transnational knowledge dissemination or if they were rather a manifestation of national encounters. This research is based on the minutes and membership lists found within conference proceedings of the “Congrès internationale médecine mentale”, “Congrès international de neurologie, psychiatrie et de physiologie”, “Congrès international de l’assistance aux aliéné” and the “Congrès international de médecine” that also often included a section dedicated to psychiatry. These all took place between the 1860’s and the first decade of the twentieth century. [less ▲]

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See detailScaling of urban heat island & NO2 with urban population: a meta-analysis
Wei, Yufei UL; Caruso, Geoffrey UL; Lemoy, Rémi

Scientific Conference (2019, December 05)

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See detailAccommodation of non-nationals in Luxembourg
Wronska, Iwona; Murdock, Elke UL

Scientific Conference (2019, December 05)

The Grand Duchy of Luxembourg within its current borders was established in the end of 19th century. In the space of less than 150 years the population of this state more than doubled - largely ... [more ▼]

The Grand Duchy of Luxembourg within its current borders was established in the end of 19th century. In the space of less than 150 years the population of this state more than doubled - largely attributable to immigration. Today, 48% of the population are foreigners. We would like to argue that the current immigration policy of Luxembourg is based on the strategy of accommodation. We can identify three major pillars of this strategy. The first pillar creates welcome conditions to adaptation within the host society. The second pillar brings liberal provisions for naturalization and the third pillar offers open and generous admission of refugees. [less ▲]

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See detailOn the Formal Structure of Rules in Conflict of Laws
Markovich, Réka UL

in Legal Knowledge and Information Systems 2019 (proceedings) (2019, December)

Law has different methods and principles to resolve conflicts between norms, most of these come from Roman Law, they are well-known and much discussed. There is a whole branch of law, though, which is ... [more ▼]

Law has different methods and principles to resolve conflicts between norms, most of these come from Roman Law, they are well-known and much discussed. There is a whole branch of law, though, which is much less discussed while having been created exactly in order to resolve special conflicts: conflict of laws. This system within Private International Law is dedicated to providing metarules in legal situations where more than one national legal systems’ rules could be applied: CoL rules indirectly settle the situation by declaring which one’s should. The formal representation of how these rules work contributes not only to the modelling of this branch of law but also provides methodologies for concerns arising from other conflicting normative systems, such as ethically sensitive situations where there are multiple stakeholders with different moral backgrounds. [less ▲]

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See detailAutomatic Software Tuning of Parallel Programs for Energy-Aware Executions
Varrette, Sébastien UL; Pinel, Frédéric UL; Kieffer, Emmanuel UL et al

in Proc. of 13th Intl. Conf. on Parallel Processing and Applied Mathematics (PPAM 2019) (2019, December)

For large scale systems, such as data centers, energy efficiency has proven to be key for reducing capital, operational expenses and environmental impact. Power drainage of a system is closely related to ... [more ▼]

For large scale systems, such as data centers, energy efficiency has proven to be key for reducing capital, operational expenses and environmental impact. Power drainage of a system is closely related to the type and characteristics of workload that the device is running. For this reason, this paper presents an automatic software tuning method for parallel program generation able to adapt and exploit the hardware features available on a target computing system such as an HPC facility or a cloud system in a better way than traditional compiler infrastructures. We propose a search based approach combining both exact methods and approximated heuristics evolving programs in order to find optimized configurations relying on an ever-increasing number of tunable knobs i.e., code transformation and execution options (such as the num- ber of OpenMP threads and/or the CPU frequency settings). The main objective is to outperform the configurations generated by traditional compiling infrastructures for selected KPIs i.e., performance, energy and power usage (for both for the CPU and DRAM), as well as the runtime. First experimental results tied to the local optimization phase of the proposed framework are encouraging, demonstrating between 8% and 41% improvement for all considered metrics on a reference benchmark- ing application (i.e., Linpack). This brings novel perspectives for the global optimization step currently under investigation within the presented framework, with the ambition to pave the way toward automatic tuning of energy-aware applications beyond the performance of the current state-of-the-art compiler infrastructures. [less ▲]

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See detailSafer UAV Piloting: A Robust Sense-and-Avoid Solution for Remotely Piloted Quadrotor UAVs in Complex Environments
Wang, Min UL; Voos, Holger UL

in Safer UAV Piloting: A Robust Sense-and-Avoid Solution for Remotely Piloted Quadrotor UAVs in Complex Environments (2019, December)

Current commercial UAVs are to a large extent remotely piloted by amateur human pilots. Due to lack of teleoperation experience or skills, they often drive the UAVs into collision. Therefore, in order to ... [more ▼]

Current commercial UAVs are to a large extent remotely piloted by amateur human pilots. Due to lack of teleoperation experience or skills, they often drive the UAVs into collision. Therefore, in order to ensure safety of the UAV as well as its surroundings, it is necessary for the UAV to boast the capability of detecting emergency situation and acting on its own when facing imminent threat. However, the majority of UAVs currently available in the market are not equipped with such capability. To fill in the gap, in this paper we present a complete sense-and-avoid solution for assisting unskilled pilots in ensuring a safe flight. Particularly, we propose a novel nonlinear vehicle control system which takes into account of sensor characteristics, an emergency evaluation policy and a novel optimization-based avoidance control strategy. The effectiveness of the proposed approach is demonstrated and validated in simulation with multiple moving objects. [less ▲]

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See detailCryptanalysis of CLT13 Multilinear Maps with Independent Slots
Coron, Jean-Sébastien UL; Notarnicola, Luca UL

in Advances in Cryptology – ASIACRYPT 2019, 25th International Conference on the Theory and Application of Cryptology and Information Security, Kobe, Japan, December 8–12, 2019, Proceedings, Part II (2019, December)

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See detailLinear system identification from ensemble snapshot observations
Aalto, Atte UL; Goncalves, Jorge UL

in Proceedings of the IEEE Conference on Decision and Control (2019, December)

Developments in transcriptomics techniques have caused a large demand in tailored computational methods for modelling gene expression dynamics from experimental data. Recently, so-called single-cell ... [more ▼]

Developments in transcriptomics techniques have caused a large demand in tailored computational methods for modelling gene expression dynamics from experimental data. Recently, so-called single-cell experiments have revolutionised genetic studies. These experiments yield gene expression data in single cell resolution for a large number of cells at a time. However, the cells are destroyed in the measurement process, and so the data consist of snapshots of an ensemble evolving over time, instead of time series. The problem studied in this article is how such data can be used in modelling gene regulatory dynamics. Two different paradigms are studied for linear system identification. The first is based on tracking the evolution of the distribution of cells over time. The second is based on the so-called pseudotime concept, identifying a common trajectory through the state space, along which cells propagate with different rates. Therefore, at any given time, the population contains cells in different stages of the trajectory. Resulting methods are compared in numerical experiments. [less ▲]

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See detailTemporal 3D Human Pose Estimation for Action Recognition from Arbitrary Viewpoints
Adel Musallam, Mohamed; Baptista, Renato UL; Al Ismaeil, Kassem UL et al

in 6th Annual Conf. on Computational Science & Computational Intelligence, Las Vegas 5-7 December 2019 (2019, December)

This work presents a new view-invariant action recognition system that is able to classify human actions by using a single RGB camera, including challenging camera viewpoints. Understanding actions from ... [more ▼]

This work presents a new view-invariant action recognition system that is able to classify human actions by using a single RGB camera, including challenging camera viewpoints. Understanding actions from different viewpoints remains an extremely challenging problem, due to depth ambiguities, occlusion, and a large variety of appearances and scenes. Moreover, using only the information from the 2D perspective gives different interpretations for the same action seen from different viewpoints. Our system operates in two subsequent stages. The first stage estimates the 2D human pose using a convolution neural network. In the next stage, the 2D human poses are lifted to 3D human poses, using a temporal convolution neural network that enforces the temporal coherence over the estimated 3D poses. The estimated 3D poses from different viewpoints are then aligned to the same camera reference frame. Finally, we propose to use a temporal convolution network-based classifier for cross-view action recognition. Our results show that we can achieve state of art view-invariant action recognition accuracy even for the challenging viewpoints by only using RGB videos, without pre-training on synthetic or motion capture data. [less ▲]

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See detailA Lightweight Implementation of NTRU Prime for the Post-Quantum Internet of Things
Cheng, Hao UL; Dinu, Dumitru-Daniel; Groszschädl, Johann UL et al

in Laurent, Maryline; Giannetsos, Thanassis (Eds.) Information Security Theory and Practice, 13th IFIP WG 11.2 International Conference, WISTP 2019, Paris, France, December 11–12, 2019, Proceedings (2019, December)

The dawning era of quantum computing has initiated various initiatives for the standardization of post-quantum cryptosystems with the goal of (eventually) replacing RSA and ECC. NTRU Prime is a variant of ... [more ▼]

The dawning era of quantum computing has initiated various initiatives for the standardization of post-quantum cryptosystems with the goal of (eventually) replacing RSA and ECC. NTRU Prime is a variant of the classical NTRU cryptosystem that comes with a couple of tweaks to minimize the attack surface; most notably, it avoids rings with "worrisome" structure. This paper presents, to our knowledge, the first assembler-optimized implementation of Streamlined NTRU Prime for an 8-bit AVR microcontroller and shows that high-security lattice-based cryptography is feasible for small IoT devices. An encapsulation operation using parameters for 128-bit post-quantum security requires 8.2 million clock cycles when executed on an 8-bit ATmega1284 microcontroller. The decapsulation is approximately twice as costly and has an execution time of 15.6 million cycles. We achieved this performance through (i) new low-level software optimization techniques to accelerate Karatsuba-based polynomial multiplication on the 8-bit AVR platform and (ii) an efficient implementation of the coefficient modular reduction written in assembly language. The execution time of encapsulation and decapsulation is independent of secret data, which makes our software resistant against timing attacks. Finally, we assess the performance one could theoretically gain by using a so-called product-form polynomial as part of the secret key and discuss potential security implications. [less ▲]

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See detailUC Priced Oblivious Transfer with Purchase Statistics and Dynamic Pricing
Damodaran, Aditya Shyam Shankar UL; Dubovitskaya, Maria; Rial, Alfredo UL

in Progress in Cryptology – INDOCRYPT 2019 (2019, December)

Priced oblivious transfer (POT) is a cryptographic protocol that can be used to protect customer privacy in e-commerce applications. Namely, it allows a buyer to purchase an item from a seller without ... [more ▼]

Priced oblivious transfer (POT) is a cryptographic protocol that can be used to protect customer privacy in e-commerce applications. Namely, it allows a buyer to purchase an item from a seller without disclosing to the latter which item was purchased and at which price. Unfortunately, existing POT schemes have some drawbacks in terms of design and functionality. First, the design of existing POT schemes is not modular. Typically, a POT scheme extends a k-out-of-N oblivious transfer (OT) scheme by adding prices to the items. However, all POT schemes do not use OT as a black-box building block with certain security guarantees. Consequently, security of the OT scheme needs to be reanalyzed while proving security of the POT scheme, and it is not possible to swap the underlying OT scheme with any other OT scheme. Second, existing POT schemes do not allow the seller to obtain any kind of statistics about the buyer's purchases, which hinders customer and sales management. Moreover, the seller is not able to change the prices of items without restarting the protocol from scratch. We propose a POT scheme that addresses the aforementioned drawbacks. We prove the security of our POT in the UC framework. We modify a standard POT functionality to allow the seller to receive aggregate statistics about the buyer's purchases and to change prices dynamically. We present a modular construction for POT that realizes our functionality in the hybrid model. One of the building blocks is an ideal functionality for OT. Therefore, our protocol separates the tasks carried out by the underlying OT scheme from the additional tasks needed by a POT scheme. Thanks to that, our protocol is a good example of modular design and can be instantiated with any secure OT scheme as well as other building blocks without reanalyzing security from scratch. [less ▲]

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See detailThe Impact of Human Mobility on Edge Data Center Deployment in Urban Environments
Vitello, Piergiorgio UL; Capponi, Andrea UL; Fiandrino, Claudio UL et al

in IEEE Global Communications Conference (GLOBECOM), Waikoloa, HI, USA, 2019 (2019, December)

Multi-access Edge Computing (MEC) brings storage and computational capabilities at the edge of the network into so-called Edge Data Centers (EDCs) to better low-latency applications. To this end ... [more ▼]

Multi-access Edge Computing (MEC) brings storage and computational capabilities at the edge of the network into so-called Edge Data Centers (EDCs) to better low-latency applications. To this end, effective placement of EDCs in urban environments is key for proper load balance and to minimize outages. In this paper, we specifically tackle this problem. To fully understand how the computational demand of EDCs varies, it is fundamental to analyze the complex dynamics of cities. Our work takes into account the mobility of citizens and their spatial patterns to estimate the optimal placement of MEC EDCs in urban environments in order to minimize outages. To this end, we propose and compare two heuristics. In particular, we present the mobility-aware deployment algorithm (MDA) that outperforms approaches that do not consider citizens mobility. Simulations are conducted in Luxembourg City by extending the CrowdSenSim simulator and show that efficient EDCs placement significantly reduces outages. [less ▲]

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See detailFrom tech to bench: Deep Learning pipeline for image segmentation of high-throughput high-content microscopy data
Garcia Santa Cruz, Beatriz UL; Jarazo, Javier UL; Saraiva, Claudia UL et al

Poster (2019, November 29)

Automation of biological image analysis is essential to boost biomedical research. The study of complex diseases such as neurodegenerative diseases calls for big amounts of data to build models towards ... [more ▼]

Automation of biological image analysis is essential to boost biomedical research. The study of complex diseases such as neurodegenerative diseases calls for big amounts of data to build models towards precision medicine. Such data acquisition is feasible in the context of high-throughput screening in which the quality of the results relays on the accuracy of image analysis. Although the state-of-the-art solutions for image segmentation employ deep learning approaches, the high cost of manual data curation is hampering the real use in current biomedical research laboratories. Here, we propose a pipeline that employs deep learning not only to conduct accurate segmentation but also to assist with the creation of high-quality datasets in a less time-consuming solution for the experts. Weakly-labelled datasets are becoming a common alternative as a starting point to develop real-world solutions. Traditional approaches based on classical multimedia signal processing were employed to generate a pipeline specifically optimized for the high-throughput screening images of iPSC fused with rosella biosensor. Such pipeline produced good segmentation results but with several inaccuracies. We employed the weakly-labelled masks produced in this pipeline to train a multiclass semantic segmentation CNN solution based on U-net architecture. Since a strong class imbalance was detected between the classes, we employed a class sensitive cost function: Dice coe!cient. Next, we evaluated the accuracy between the weakly-labelled data and the trained network segmentation using double-blind tests conducted by experts in cell biology with experience in this type of images; as well as traditional metrics to evaluate the quality of the segmentation using manually curated segmentations by cell biology experts. In all the evaluations the prediction of the neural network overcomes the weakly-labelled data quality segmentation. Another big handicap that complicates the use of deep learning solutions in wet lab environments is the lack of user-friendly tools for non-computational experts such as biologists. To complete our solution, we integrated the trained network on a GUI built on MATLAB environment with non-programming requirements for the user. This integration allows conducting semantic segmentation of microscopy images in a few seconds. In addition, thanks to the patch-based approach it can be employed in images with different sizes. Finally, the human-experts can correct the potential inaccuracies of the prediction in a simple interactive way which can be easily stored and employed to re-train the network to improve its accuracy. In conclusion, our solution focuses on two important bottlenecks to translate leading-edge technologies in computer vision to biomedical research: On one hand, the effortless obtention of high-quality datasets with expertise supervision taking advantage of the proven ability of our CNN solution to generalize from weakly-labelled inaccuracies. On the other hand, the ease of use provided by the GUI integration of our solution to both segment images and interact with the predicted output. Overall this approach looks promising for fast adaptability to new scenarios. [less ▲]

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See detailDreaming of Constructivist Technology Integration Strategies in Future Teacher Students
Reuter, Robert UL; Busana, Gilbert UL

Scientific Conference (2019, November 27)

Based on previous experiences in preparing future teachers for technology integration (Reuter & Busana, 2017), and based on the recommendations from Kolb’s (2017) Triple E framework about effective uses ... [more ▼]

Based on previous experiences in preparing future teachers for technology integration (Reuter & Busana, 2017), and based on the recommendations from Kolb’s (2017) Triple E framework about effective uses of ICT in education, we have adapted the Educational Technology course in our Initial Teacher Training. Over the years, we have indeed observed that, when given the choice of the type of technology integration strategies, many students designed ICT-based learning and teaching scenarios that implemented a rather teacher-centred teaching model (Roblyer & Doering, 2013). These scenarios were often far from innovative nor did they implement the disruptive potential of ICT in education (Christensen, Horn & Johnson, 2008). In the winter semester 2018-2019 we thus decided to ask our students to design and develop constructivist technology integration scenarios. We assessed the success of this adaptation with the help of our own observations, the semester reports produced by our students and their answers to an end-of-semester course evaluation. In general, we saw that students were able to design rather attractive constructivist learning activities. We also observed that our students were quite surprised that such activities do not require complicated and expensive tools, but that they can be implemented with standard productivity tools. [less ▲]

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See detailA professional development course in translanguaging: Challenges and opportunities
Aleksic, Gabrijela UL; Dzoen, Bebic-Crestany

Scientific Conference (2019, November 27)

In Luxembourg, the new law in 2017 has declared multilingual early education mandatory. Not only that teachers need to help children develop their Luxembourgish, but also they need to familiarize them ... [more ▼]

In Luxembourg, the new law in 2017 has declared multilingual early education mandatory. Not only that teachers need to help children develop their Luxembourgish, but also they need to familiarize them with French and value their home languages. In order to support preschool teachers in this endeavour, our project aims to: (1) offer a professional development (PD) course in translanguaging, (2) involve children’s families to reinforce home-school collaboration, and (3) foster children’s cognitive, linguistic, and socio-emotional engagement in the classroom. We use a panoply of measures to reach our aims: focus groups and teacher questionnaires (aim 1), parent questionnaires and interviews (aim 2), a test in early literacy and numeracy in school and home languages, teacher assessment of children’s socio-emotional development and video observations with children (aim 3). Translanguaging, the main topic of our 22 hour PD course (June – December 2019), is the use of a full linguistic repertoire to make meaning (Otheguy, García, & Reid, 2015). In eight sessions, we explore multilingual ecology, parental involvement, and oracy and early literacy. We will present preliminary findings of the focus groups with teachers and tests in early literacy and numeracy in children’s home and school languages. Challenges and opportunities that emerged during the course will be explored as well. [less ▲]

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See detailDeveloping Multilingual Pedagogies in Early Childhood: a review of the project MuLiPEC
Aleksic, Claudine UL; Aleksic, Gabrijela UL; Mortini, Simone UL et al

Scientific Conference (2019, November 27)

Developing Multilingual Pedagogies in Early Childhood: a review of the project The project MuLiPEC (2016-2019) addresses the need for multilingual pedagogies in early childhood education in Luxembourg. It ... [more ▼]

Developing Multilingual Pedagogies in Early Childhood: a review of the project The project MuLiPEC (2016-2019) addresses the need for multilingual pedagogies in early childhood education in Luxembourg. It offered a professional development (PD) course to develop the practitioners’ knowledge and skills in relation to multilingualism and effective pedagogies as well as their practices, and analysed the effects of the PD on the practitioners and the children’s languaging. We offered a first 15-hour course to 46 practitioners from formal and non-formal education settings. Of these, seven continued during one academic year. They were coached and took part in six network meetings where we discussed their practices. To analyse the results, we drew on observations of the PD and in the research settings, video-recorded activities, and interviews. The results show that all 46 participants opened up to multilingual education and deepened their understanding of multilingualism, language development and multilingual pedagogies. Furthermore, the seven focus practitioners implemented activities in multiple languages and deployed effective language supportive strategies. Five of them developed holistic and child-centred multilingual pedagogies. This paper presents these positive findings and raises questions related to the sustainability of PD course and the need to continue the implementation of these effective pedagogies. [less ▲]

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See detailA case study on the impact of masking moving objects on the camera pose regression with CNNs
Cimarelli, Claudio UL; Cazzato, Dario UL; Olivares Mendez, Miguel Angel UL et al

in 2019 16th IEEE International Conference on Advanced Video and Signal Based Surveillance (AVSS) (2019, November 25)

Robot self-localization is essential for operating autonomously in open environments. When cameras are the main source of information for retrieving the pose, numerous challenges are posed by the presence ... [more ▼]

Robot self-localization is essential for operating autonomously in open environments. When cameras are the main source of information for retrieving the pose, numerous challenges are posed by the presence of dynamic objects, due to occlusion and continuous changes in the appearance. Recent research on global localization methods focused on using a single (or multiple) Convolutional Neural Network (CNN) to estimate the 6 Degrees of Freedom (6-DoF) pose directly from a monocular camera image. In contrast with the classical approaches using engineered feature detector, CNNs are usually more robust to environmental changes in light and to occlusions in outdoor scenarios. This paper contains an attempt to empirically demonstrate the ability of CNNs to ignore dynamic elements, such as pedestrians or cars, through learning. For this purpose, we pre-process a dataset for pose localization with an object segmentation network, masking potentially moving objects. Hence, we compare the pose regression CNN trained and/or tested on the set of masked images and the original one. Experimental results show that the performances of the two training approaches are similar, with a slight reduction of the error when hiding occluding objects from the views. [less ▲]

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See detailAu-delà du cours magistral: Vers des apprentissages autonomes et collaboratifs basés sur de « grandes questions »
Busana, Gilbert UL; Reuter, Robert UL

Scientific Conference (2019, November 22)

Nous enseignions depuis quelques années un cours de première année sur "l'éducation à l'ère numérique", dans la formation initiale des futur-e-s enseignant-e-s du fondamental, sous forme d’un cours ... [more ▼]

Nous enseignions depuis quelques années un cours de première année sur "l'éducation à l'ère numérique", dans la formation initiale des futur-e-s enseignant-e-s du fondamental, sous forme d’un cours magistral afin de véhiculer certaines connaissances théoriques et pratiques dans ce domaine. Cependant, nous avons observé au cours des dernières années que (1) de nombreux étudiants échouaient à l'examen et que (2) beaucoup d'entre eux, lorsqu'ils étaient en 4e année, avaient oublié la plupart des fondements. Ces considérations nous ont amenés à repenser et à remanier nos méthodes d'enseignement et notre façon d'évaluer les résultats d'apprentissage des étudiant-e-s. Après une première implémentation de notre nouvelle approche pédagogique combinant diverses méthodes actives d'apprentissage au semestre d’hiver 2018 (décrite et réfléchie dans Reuter & Busana, 2018), nous avons effectué quelques modifications basées (a) sur nos propres observations et réflexions ainsi que (b) sur les commentaires des étudiant-e-s tirées de l’évaluation du cours (organisée par notre université). Dès à présent, plutôt que de les faire travailler sur de « grandes questions » (c.-à-d. des questions pour lesquelles il n'y a pas de réponses simples et faciles à consulter) au cours des séances en présentiel, nous demandons maintenant à nos étudiant-e-s (1) de construire individuellement des connaissances en amont du séminaire sur base de ressources fournies ou tirés de recherches bibliographiques autonomes ; (2) de les présenter, discuter et développer de manière collaborative en petits groupes pendant les séminaires ; puis (3) de les partager et discuter avec nous et leurs pairs et finalement (4) de les conserver dans un portfolio numérique personnel. L’évaluation des apprentissages des étudiant-e-s est effectuée à l’aide de ce portfolio numérique en fin de semestre. [less ▲]

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See detailDie Entstehung einer Hauptstadtregion als deutsch-belgische Beziehungsgeschichte
Brüll, Christoph UL

Scientific Conference (2019, November 22)

Vom 14. Mai - 23. Juli und vom 19. September - 31.Oktober 1972 fand zunächst im Kölner Museum Schnütgen und dann in den Brüsseler Musées Royaux d’Art et d’Histoire die bis heute größte Schau rheinisch ... [more ▼]

Vom 14. Mai - 23. Juli und vom 19. September - 31.Oktober 1972 fand zunächst im Kölner Museum Schnütgen und dann in den Brüsseler Musées Royaux d’Art et d’Histoire die bis heute größte Schau rheinisch-maasländischer Kunst statt. Unter dem Titel „Rhein und Maas. Kunst und Kultur 800-1400“ wurde sie zu einem großen Publikumserfolg, der auch in der Scientific Community der Kunsthistoriker einige Aufmerksamkeit erregte. Die Entstehung der Ausstellung sagt einiges über die Geschichte der Wissenschaftsbeziehungen zwischen Deutschland und Belgien seit 1945 aus, aber auch, so die Ausgangshypothese meines Beitrags, über die Veränderungen der in Belgien vorherrschenden Mental Maps von Deutschland seit der Verlagerung des politischen Schwerpunktes an den Rhein mit der Gründung der Bundesrepublik. Der belgische Deutschlanddiskurs knüpfte dabei durchaus an bereits bestehende Deutschlandbilder an, die gerade das Maasland als Zwischenraum inszenierten , doch kam durch das Zusammenrücken der westeuropäischen Länder im Zuge von Kaltem Krieg und beginnender europäischer Integration, gerade auch unter dem Signum des Abendlandes, eine neue Dimension ins Spiel. Mentalitätsgeschichtlich hob die rheinische Bonner Republik die durch den Ersten Weltkrieg hervorgerufene Distanz zwischen dem belgischen Staat und (West-)Deutschland auf, politikgeschichtlich fanden deutsche und belgische „Suche nach Sicherheit“ (E. Conze) ein enges Kooperationsfeld. Zum Zentrum der belgischen Aktivität im Rheinland wurde Köln, das nach dem durch die Wahl als Regierungssitz notwendig gewordenen Verlassen Bonns durch die belgischen Truppen in Deutschland 1950 zu deren neuem Hauptquartier wurde. Dort etablierte sich zudem rasch das Belgische Haus als Drehscheibe für politischen, konsularischen, aber auch kulturellen Austausch. Die Ausstellung „Rhein und Maas“ dient als Aufhänger für den Beitrag, der sowohl das Ende einer langen Nachkriegszeit als auch das Ankommen Belgiens in der Bonner Republik herausstellen kann. Auch die Anfang der 1970er Jahre erfolgten ersten gegenseitigen Staatsbesuche geben Aufschluss über Inszenierung und Wahrnehmung der Hauptstadtregion. Der Beitrag wirft somit eine beziehungsgeschichtliche Perspektive auf Bonn-Köln-Düsseldorf zwischen 1949 und den 1970er Jahren und fragt mit Bezug auf die Hauptstadtregion auf die belgische(n) Wahrnehmung(en) des Rheinischen, aber auch nach Rückwirkungen auf Brüssel als belgischer und europäischer Hauptstadt. [less ▲]

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See detailToward fluid-structure-piezoelectric simulations applied to flow-induced energy harvesters
Hoareau, Christophe UL; Shang, Lan UL; Zilian, Andreas UL

Poster (2019, November 15)

The subject deals with the simulation of flow-induced energy harvesters. We focus in particular on the modelling of autonomous piezo-ceramic power generators to convert ambient fluid-flow energy into ... [more ▼]

The subject deals with the simulation of flow-induced energy harvesters. We focus in particular on the modelling of autonomous piezo-ceramic power generators to convert ambient fluid-flow energy into electrical energy. The vibrations of an immersed electromechanical structure with large amplitude have to be taken into account in that case. One challenge consists in modelling and predicting the nonlinear coupled dynamic behaviour for the improved design of such devices. The set of governing equations is expressed in integral form, using the method of weighted residuals, and discretized with finite elements using the open source package FEniCS. Preliminary results of separated problems using FEniCS will be detailed and discussed (e.g. Navier-Stokes with or without moving meshes, nonlinear elasticity, aeroelasticity and electromechanical coupling). The objective is to validate each problem independently before coupling all the phenomena in a monolithic framework. Those simulations involve nonlinearities at many levels of modeling. The perspective of using reduced order models to limit the computational cost (in time and memory) will be discussed in an outlook to this work. [less ▲]

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See detailAuthenticated Key Distribution: When the Coupon Collector is Your Enemy
Beunardeau, Marc; El Orche, Fatima Ezzahra UL; Maimut, Diana et al

in Innovative Security Solutions for Information Technology and Communications (2019, November 14)

We introduce new authenticated key exchange protocols which on the one hand do not resort to standard public key setups with corresponding assumptions of computationally hard problems, but on the other ... [more ▼]

We introduce new authenticated key exchange protocols which on the one hand do not resort to standard public key setups with corresponding assumptions of computationally hard problems, but on the other hand, are more efficient than distributing symmetric keys among the participants. To this end, we rely on a trusted central authority distributing key material whose size is independent of the total number of users, and which allows the users to obtain shared secret keys. We analyze the security of our construction, taking into account various attack models. Importantly, only symmetric primitives are needed in the protocol making it an alternative to quantum-safe key exchange protocols which rely on hardness assumptions. [less ▲]

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See detailOral History as a multimedia and multidimensional presentation challenge
Lambert, Douglas UL

Scientific Conference (2019, November 13)

Oral History is a multidisciplinary, multinational field based on a format of recorded, usually sit-down interviews, where the past is documented through personal narratives of life experience. In the ... [more ▼]

Oral History is a multidisciplinary, multinational field based on a format of recorded, usually sit-down interviews, where the past is documented through personal narratives of life experience. In the early 2000’s, a new approach to processing and managing oral histories was introduced based on timecode indexing made possible by software environments. This work can be referred to as Oral History Digital Indexing (OHDI), and it represents a suite of activities, tools, methods, and interfaces that have made oral histories more accessible both with and without transcripts, whilst reconnecting navigable text to original recordings for listening and watching. OHDI allows for oral history to be represented in visual, dynamic forms far more palatable to users than the previous default--a collection of transcripts. Pioneering OHDI work was done by Michael Frisch and The Randforce Associates, with whom the author worked with on a number of consulting projects between 2002 and 2018. The focus of these projects was distinctly on comprehensive timecode indexing, the use of annotation as an alternative to word-for-word transcription, and deployment of custom controlled vocabularies (CVs) organized visually as a spatially-meaningful content map. These CVs function like back-of-the-book term indexes providing better “front end” user access, but they have they also been adapted for research applications to organize sets of qualitative analysis codes. Through a post-doctoral research position at the University of Luxembourg, the author is introducing and integrating these OHDI methods into oral history development plans in Luxembourg. Several representative tools, interfaces, and CVs used to make oral histories more multimedia and multidimensional will be presented, all of which will be influential to the in-development “Luxembourgish Oral History Initiative.” [less ▲]

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See detailPost-collusion security and distance bounding
Mauw, Sjouke UL; Smith, Zachary Daniel UL; Trujillo Rasua, Rolando UL et al

in Post-collusion security and distance bounding (2019, November 11)

Verification of cryptographic protocols is traditionally built upon the assumption that participants have not revealed their long-term keys. However, in some cases, participants might collude to defeat ... [more ▼]

Verification of cryptographic protocols is traditionally built upon the assumption that participants have not revealed their long-term keys. However, in some cases, participants might collude to defeat some security goals, without revealing their long-term secrets. We develop a model based on multiset rewriting to reason about collusion in security protocols. We introduce the notion of postcollusion security, which verifies security properties claimed in sessions initiated after collusion occurred. We use post-collusion security to analyse terrorist fraud on protocols for securing physical proximity, known as distance-bounding protocols. In a terrorist fraud attack, agents collude to falsely prove proximity, whilst no further false proximity proof can be issued without further collusion. Our definitions and the Tamarin prover are used to develop a modular framework for verification of distance-bounding protocols that accounts for all types of attack from literature. We perform a survey of over 25 protocols, which include industrial protocols such as Mastercard’s contactless payment PayPass and NXP’s MIFARE Plus with proximity check. For the industrial protocols we confirm attacks, propose fixes, and deliver computer-verifiable security proofs of the repaired versions [less ▲]

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See detailPOSTER: Traffic Splitting to Counter Website Fingerprinting
de La Cadena Ramos, Augusto Wladimir UL; Mitseva, Asya UL; Pennekamp, Jan et al

Poster (2019, November 11)

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See detailThe 2004 Afghan Constitution and Islam Merits and Challenges
Al Hajjaji, Shams Al Din UL

Scientific Conference (2019, November 11)

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See detailWorkplace bullying exposure and subjective well-being – The mediating role of the frustration of the need for relatedness. A longitudinal six-wave study
Sischka, Philipp UL; Steffgen, Georges UL

Scientific Conference (2019, November 08)

Workplace bullying is a serious phenomenon that has serious detrimental effects on victim’s health, attitudes, and work-related behavior. Drawing on self-determination theory, we propose that bullying ... [more ▼]

Workplace bullying is a serious phenomenon that has serious detrimental effects on victim’s health, attitudes, and work-related behavior. Drawing on self-determination theory, we propose that bullying exposure thwarts employee’s need for relatedness with the result of decreased well-being. Studies examining these mechanisms used either a cross-sectional design (Trépanier et al., 2013) or a longitudinal design with (not theoretically justified) long time intervals (i.e., 12-month time lag; Trépanier et al., 2015). Therefore, the aim of our study was to test this mediation in a longitudinal design with much shorter time intervals (i.e. monthly), whether to see if the bullying exposure also shows short-term effects on well-being. A six-wave online survey design with monthly time lag was employed and data were collected among U.S. employees. The sample consists of 1,595 respondents (55.8% females, n=890, ageM = 36.9, ageSD =10.3). Workplace bullying exposure was assessed with the S-NAQ (Notelaers et al., 2018), frustration of the need for relatedness with the Psychological Needs Thwarting Scale (Bartholomew et al., 2011) and well-being with the WHO-5 well-being-index (Topp et al., 2015). Cross-lagged mediation analysis within a structural equation modeling framework confirmed the mediation model: Bullying exposure was significantly related to a change in frustration of relatedness and frustration of relatedness was significantly related to a change in well-being across all waves. The study findings advance the field through showing that bullying exposure has not only a long-term effect on well-being but also a short one, and that this effect is mediated through the frustration of relatedness. [less ▲]

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See detailNeed for Cognition across school tracks: The importance of learning environments
Colling, Joanne UL; Wollschläger, Rachel UL; Keller, Ulrich UL et al

Scientific Conference (2019, November 06)

Detailed reference viewed: 66 (7 UL)
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See detailSimilarities and differences of value-added scores from models with different covariates: A cluster analysis
Levy, Jessica UL; Brunner, Martin; Keller, Ulrich UL et al

Scientific Conference (2019, November 06)

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See detailThe stability of academic self-concept profiles – a latent transition analysis
Franzen, Patrick UL; Arens, A. Katrin; Niepel, Christoph UL

Poster (2019, November 06)

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See detailDimensional and Social Comparison Effects on Domain-Specific Academic Self-Concepts and Interests with First- and Third-Grade Students
van der Westhuizen, Lindie UL; Arens, Katrin; Keller, Ulrich UL et al

Scientific Conference (2019, November 06)

Academic self-concepts (ASCs) are self-perceptions of one’s own academic abilities. The internal/external frame of reference (I/E) model (Marsh, 1986) explains the formation of domain-specific ASCs ... [more ▼]

Academic self-concepts (ASCs) are self-perceptions of one’s own academic abilities. The internal/external frame of reference (I/E) model (Marsh, 1986) explains the formation of domain-specific ASCs through a combination of social (i.e. comparing one’s achievement in one domain with the achievement of others in the same domain) and dimensional (i.e. comparing one’s achievement in one domain with one’s achievement in another domain) comparisons. This results into positive achievement-self-concept relations within the math and verbal domains, but into negative achievement-self-concept relations across these domains. The generalized internal/external frame of reference (GI/E) model (Möller, Müller-Kalthoff, Helm, Nagy, & Marsh, 2015) extends the I/E model to the formation of other domain-specific academic self-beliefs such as interest. Research on the validity of the (G)I/E model for elementary school children is limited, especially for first-graders. This study examined the associations between verbal and math achievement and corresponding domain-specific self-concepts and interests for first-graders and third-graders. Two fully representative Luxembourgish first-grader cohorts and two fully representative third-graders cohorts (N=21,192) were used. The analyses were based on structural equation modeling. The findings fully supported the (G)I/E model for third-graders: Achievement was positively related to self-concept and interest within matching domains. Negative relations were found between achievement and self-concept and between achievement and interest across domains. For first-graders, achievement was positively related to self-concept and interest within matching domains. However, the majority of cross-domain relations were non-significant, except for the negative path between math achievement and verbal interest. Hence, while the formation of domain-specific ASCs and interests seem to rely on social and dimensional comparisons for third-graders, only social comparisons seem to be in operation for first-graders. Gender and cohort invariance was established for both grade levels. The findings are discussed within the framework of ASC differentiation and dimensional comparison theory applied to elementary school students. [less ▲]

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See detailMath and Reading Difficulties in a Multilingual Educational Setting
Martini, Sophie Frédérique UL; Fischbach, Antoine UL; Ugen, Sonja UL

Scientific Conference (2019, November 06)

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See detailOptimum Design for Sparse FDA-MIMO Automotive Radar
Sedighi, Saeid UL; Shankar, Bhavani UL; Mishra, Kumar Vijay et al

in Sedighi, Saeid; Shankar, Bhavani; Mishra, Kumar Vijay (Eds.) et al Optimum Design for Sparse FDA-MIMO Automotive Radar (2019, November 03)

Automotive radars usually employ multiple-input multiple-output (MIMO) antenna arrays to achieve high azimuthal resolution with fewer elements than a phased array. Despite this advantage, hardware costs ... [more ▼]

Automotive radars usually employ multiple-input multiple-output (MIMO) antenna arrays to achieve high azimuthal resolution with fewer elements than a phased array. Despite this advantage, hardware costs and desired radar size limits the usage of more antennas in the array. Similar trade-off is encountered while attempting to achieve high range resolution which is limited by the signal bandwidth. However, nowadays given the demand for spectrum from communications services, wide bandwidth is not readily available. To address these issues, we propose a sparse variant of Frequency Diverse Array MIMO (FDA-MIMO) radar which enjoys the benefits of both FDA and MIMO techniques, including fewer elements, decoupling, and efficient joint estimation of target parameters. We then employ the Cram\'{e}r-Rao bound for angle and range estimation as a performance metric to design the optimal antenna placement and carrier frequency offsets for the transmit waveforms. Numerical experiments suggest that the performance of sparse FDA-MIMO radar is very close to the conventional FDA-MIMO despite 50\% reduction in the bandwidth and antenna elements. [less ▲]

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See detailEnergy-efficient Trajectory Design for UAV-enabled Wireless Communications with Latency Constraints
Tran Dinh, Hieu UL; Vu, Thang Xuan UL; Chatzinotas, Symeon UL et al

Scientific Conference (2019, November 03)

This paper studies a new energy-efficient unmanned aerial vehicle (UAV)-enabled wireless communications, where the UAV acts as a flying base station (BS) to serve the ground users (GUs) within some ... [more ▼]

This paper studies a new energy-efficient unmanned aerial vehicle (UAV)-enabled wireless communications, where the UAV acts as a flying base station (BS) to serve the ground users (GUs) within some predetermined latency limitations, e.g., requested timeout (RT). Our goal is to design the UAV trajectory to minimize the total energy consumption while satisfying the RT requirement from every GU, which is accomplished via two consecutive subproblems: traveling time minimization and energy minimization problems. Firstly, we propose two exhaustive search and heuristic algorithms based on the traveling salesman problem with time window (TSPTW) in order to minimize the UAV’s traveling time without violating the GUs’ RT requirements. While the exhaustive algorithm achieves the best performance at a high computation cost, the heuristic algorithm achieves a trade-off between the performance and complexity. Secondly, we minimize the total energy consumption, for a given trajectory, via a joint optimization of the UAV’s velocity along subsequent hops. Finally, numerical results are presented to demonstrate the effectiveness of our proposed algorithms. In particular, it is shown that the proposed solutions outperform the reference in terms of both energy consumption and outage performance. [less ▲]

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See detailActive Content Popularity Learning via Query-by-Committee for Edge Caching
Bommaraveni, Srikanth UL; Vu, Thang; Vuppala, Satyanarayana et al

Scientific Conference (2019, November 03)

Edge caching has received much attention as an effective solution to face the stringent latency requirements in 5G networks due to the proliferation of handset devices as well as data-hungry applications ... [more ▼]

Edge caching has received much attention as an effective solution to face the stringent latency requirements in 5G networks due to the proliferation of handset devices as well as data-hungry applications. One of the challenges in edge caching systems is to optimally cache strategic contents to maximize the percentage of total requests served by the edge caches. To enable the optimal caching strategy, we propose an Active Learning approach (AL) to learn and design an accurate content request prediction algorithm. Specifically, we use an AL based Query-by-committee (QBC) matrix completion algorithm with a strategy of querying the most informative missing entries of the content popularity matrix. The proposed AL framework leverage's the trade-off between exploration and exploitation of the network, and learn the user's preferences by posing queries or recommendations. Later, it exploits the known information to maximize the system performance. The effectiveness of proposed AL based QBC content learning algorithm is demonstrated via numerical results. [less ▲]

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See detailHardware Precoding Demonstration in Multi-Beam UHTS Communications under Realistic Payload Characteristics
Merlano Duncan, Juan Carlos UL; Querol Borras, Jorge UL; Maturo, Nicola UL et al

in Proceedings of the 37th International Communications Satellite Systems Conference (2019, November 01)

In this paper, we present a new hardware test-bed to demonstrate closed-loop precoded communications for interference mitigation in multi-beam ultra high throughput satellite systems under realistic ... [more ▼]

In this paper, we present a new hardware test-bed to demonstrate closed-loop precoded communications for interference mitigation in multi-beam ultra high throughput satellite systems under realistic payload and channel impairments. We build the test-bed to demonstrate a real-time channel aided precoded transmission under realistic conditions such as the power constraints and satellite-payload non-linearities. We develop a scalable architecture of an SDR platform with the DVB-S2X piloting. The SDR platform consists of two parts: analog-to-digital (ADC) and digital-to-analog (DAC) converters preceded by radio frequency (RF) front-end and Field-Programmable Gate Array (FPGA) backend. The former introduces realistic impairments in the transmission chain such as carrier frequency and phase misalignments, quantization noise of multichannel ADC and DAC and non-linearities of RF components. It allows evaluating the performance of the precoded transmission in a more realistic environment rather than using only numerical simulations. We benchmark the performance of the communication standard in realistic channel scenarios, evaluate received signal SNR, and measure the actual channel throughput using LDPC codes. [less ▲]

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See detailVon Eupen-Malmedy nach Ostbelgien. Eine deutsch-belgische Beziehungsgeschichte seit 1920
Brüll, Christoph UL

Scientific Conference (2019, November 01)

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See detailTowards Dynamic Zero Emission Zone Management for Plug-in Hybrid Buses
Seredynski, Marcin UL; Viti, Francesco UL

Scientific Conference (2019, November)

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See detailAssessing the Generalizability of code2vec Token Embeddings
Kang, Hong Jin; Bissyande, Tegawendé François D Assise UL; David, Lo

in Proceedings of the 34th IEEE/ACM International Conference on Automated Software Engineering (2019, November)

Many Natural Language Processing (NLP) tasks, such as sentiment analysis or syntactic parsing, have benefited from the development of word embedding models. In particular, regardless of the training ... [more ▼]

Many Natural Language Processing (NLP) tasks, such as sentiment analysis or syntactic parsing, have benefited from the development of word embedding models. In particular, regardless of the training algorithms, the learned embeddings have often been shown to be generalizable to different NLP tasks. In contrast, despite recent momentum on word embeddings for source code, the literature lacks evidence of their generalizability beyond the example task they have been trained for. In this experience paper, we identify 3 potential downstream tasks, namely code comments generation, code authorship identification, and code clones detection, that source code token embedding models can be applied to. We empirically assess a recently proposed code token embedding model, namely code2vec’s token embeddings. Code2vec was trained on the task of predicting method names, and while there is potential for using the vectors it learns on other tasks, it has not been explored in literature. Therefore, we fill this gap by focusing on its generalizability for the tasks we have identified. Eventually, we show that source code token embeddings cannot be readily leveraged for the downstream tasks. Our experiments even show that our attempts to use them do not result in any improvements over less sophisticated methods. We call for more research into effective and general use of code embeddings. [less ▲]

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See detailCrowdSenSim 2.0: a Stateful Simulation Platform for Mobile Crowdsensing in Smart Cities
Montori, Federico; Cortesi, Emanuele; Bedogni, Luca et al

in MSWIM '19: Proceedings of the 22nd International ACM Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems, Miami Beach, FL, USA, 2019. (2019, November)

Mobile crowdsensing (MCS) has become a popular paradigm for data collection in urban environments. In MCS systems, a crowd supplies sensing information for monitoring phenomena through mobile devices ... [more ▼]

Mobile crowdsensing (MCS) has become a popular paradigm for data collection in urban environments. In MCS systems, a crowd supplies sensing information for monitoring phenomena through mobile devices. Typically, a large number of participants is required to make a sensing campaign successful. For such a reason, it is often not practical for researchers to build and deploy large testbeds to assess the performance of frameworks and algorithms for data collection, user recruitment, and evaluating the quality of information. Simulations offer a valid alternative. In this paper, we present CrowdSenSim 2.0, a significant extension of the popular CrowdSenSim simulation platform. CrowdSenSim 2.0 features a stateful approach to support algorithms where the chronological order of events matters, extensions of the architectural modules, including an additional system to model urban environments, code refactoring, and parallel execution of algorithms. All these improvements boost the performances of the simulator and make the runtime execution and memory utilization significantly lower, also enabling the support for larger simulation scenarios. We demonstrate retro-compatibility with the older platform and evaluate as a case study a stateful data collection algorithm. [less ▲]

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See detailEffectiveness of bullying intervention teams in German schools
Böhmer, Matthias UL; Franck, André; Schirra, Helmut et al

Scientific Conference (2019, November)

In recent years, bullying has increasingly been recognized as a widespread problem - also in the school context. Numerous examples illustrate that bullying at school is not an unfortunate individual case ... [more ▼]

In recent years, bullying has increasingly been recognized as a widespread problem - also in the school context. Numerous examples illustrate that bullying at school is not an unfortunate individual case, but is often part of everyday school life. Large-scale international comparative studies such as HBSC underline the high bullying prevalence rate and thus the relevance of the topic. According to these studies, classmates bully every sixth child in Germany several times a week. Teachers have a special responsibility in dealing with bullying. As a rule, they are at the center of the action and have the task of recognizing bullying in good time and of (re)acting quickly, decisively and reflectively. Since bullying is a complex phenomenon, professional action in this area poses a major challenge. For this reason, a program against bullying introduced in some federal states explicitly aims at teachers who are trained as bullying intervention teams on three days. Currently, we are systematically evaluating this program. In particular, we are interested in the extent to which the previous knowledge of teachers on the subject of mobbing is transformed by the program into consolidated knowledge relevant for acting and decision-making. In connection with the intervention of teachers in the case of bullying, there is (a) the expression of their expectation of self-efficacy, (b) the teaching climate, i.e. the social climate in teaching situations in a class, and (c) the experience and behavior of their students. We will present and discuss first results of the effectiveness of the program. [less ▲]

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See detailConsistent Rational Argumentation in Politics (CRAP)
Benzmüller, Christoph UL; Steen, Alexander UL

Poster (2019, November)

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See detailFour Jewish stateless families between the millstones of Luxembourg authorities
Scuto, Denis UL; Bronec, Jakub UL

Scientific Conference (2019, November)

Our research, among others, attempts to find answers to the questions: How Luxembourg administration dealt with Jewish refugees who had lost their citizenship arriving to the Grand Duchy of Luxembourg ... [more ▼]

Our research, among others, attempts to find answers to the questions: How Luxembourg administration dealt with Jewish refugees who had lost their citizenship arriving to the Grand Duchy of Luxembourg from the East. Were there any particular differences between genders in the process of acceptance? Did Luxembourgish authorities distinguish or give priority to citizens of particular nations? [less ▲]

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See detailEnhanced Sketchnoting through Semantic Integration of Learning Material
Atashpendar, Aryobarzan UL; Grevisse, Christian UL; Rothkugel, Steffen UL

in Applied Informatics (2019, November)

Within the transition from pen-and-paper to digital solutions, many tablet-based note-taking apps have been developed. In addition, sketchnoting, a highly visual form of note-taking, has gained in ... [more ▼]

Within the transition from pen-and-paper to digital solutions, many tablet-based note-taking apps have been developed. In addition, sketchnoting, a highly visual form of note-taking, has gained in popularity, especially in teaching and learning. While current solutions already reduce the burden of organizing and searching through stacks of paper, they provide little support in finding additional information related to the notes, and search capabilities are mostly limited to textual queries and content. In this paper, we present a novel solution for digital sketchnoting aimed at enhancing the learning experience of students. In addition to common capabilities such as handwriting recognition, our note-taking app integrates semantic annotation and drawing recognition. Handwritten notes are recognized and passed through concept recognition and entity linking tools to enable a knowledge graph-based integration of contextually relevant learning resources. We extend traditional search capabilities by including the semantic metadata from the related material as well as enabling visual queries to find recognized sketches. Finally, resembling the exchange of paper notes among students, our app allows to share the semantically enhanced notes with other devices. [less ▲]

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See detailFeasibility of Stellar as a Blockchain-based Micropayment System
Khan, Nida UL; Ahmad, Tabrez; State, Radu UL

in Springer SmartBlock 2019 - 2nd International Conference on Smart Blockchain (2019, November)

The advent of Bitcoin was heralded as an innovation in the global monetary system, that could bring down transaction fees by circumventing the need for third parties and conduct transactions in real time ... [more ▼]

The advent of Bitcoin was heralded as an innovation in the global monetary system, that could bring down transaction fees by circumventing the need for third parties and conduct transactions in real time. The divisibility of a blockchain cryptocurrency to even fractions of a cent, caused microtransactions to become feasible to formerly non-existent denominations. These microtransactions have spurred the development of novel ways of monetizing online resources and hold the potential to aid in alleviation of poverty. The paper conducts a feasibility study on Stellar as a blockchain-based micropayment system. It highlights the computational and other issues that impedes its progress and utilizes a characterization model for micropayment systems to evaluate the efficacy of the Stellar platform. The paper conducts a comparison with the micropayment solutions from Bitcoin, Ethereum and PayPal. The paper analyzes a subset of transactions from the Stellar blockchain to aid in drawing a conclusion on the undertaken study and elaborates on the mitigation tools to enable fraud prevention in online monetary transactions. [less ▲]

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See detailCrafting Conversational Agents' Personality in a User-Centric Context
Mano Ferreira, Cátia; Höhn, Sviatlana UL

in Proceedings of the 31st Benelux Conference on Artificial Intelligence (BNAIC 2019) and the 28th Belgian Dutch Conference on Machine Learning (Benelearn 2019) (2019, November)

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See detailA Personalized Sentiment Model with Textual and Contextual Information
Guo, Siwen UL; Höhn, Sviatlana UL; Schommer, Christoph UL

in The SIGNLL Conference on Computational Natural Language Learning, Hong Kong 3-4 November 2019 (2019, November)

In this paper, we look beyond the traditional population-level sentiment modeling and consider the individuality in a person's expressions by discovering both textual and contextual information. In ... [more ▼]

In this paper, we look beyond the traditional population-level sentiment modeling and consider the individuality in a person's expressions by discovering both textual and contextual information. In particular, we construct a hierarchical neural network that leverages valuable information from a person's past expressions, and offer a better understanding of the sentiment from the expresser's perspective. Additionally, we investigate how a person's sentiment changes over time so that recent incidents or opinions may have more effect on the person's current sentiment than the old ones. Psychological studies have also shown that individual variation exists in how easily people change their sentiments. In order to model such traits, we develop a modified attention mechanism with Hawkes process applied on top of a recurrent network for a user-specific design. Implemented with automatically labeled Twitter data, the proposed model has shown positive results employing different input formulations for representing the concerned information. [less ▲]

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See detailA Multilayer Low-Altitude Airspace Model for UAV Traffic Management
Samir Labib, Nader UL; Danoy, Grégoire UL; Musial, Jedrzej et al

in Samir Labib, Nader; Danoy, Grégoire; Musial, Jedrzej (Eds.) et al 9th ACM Symposium on Design and Analysis of Intelligent Vehicular Networks and Applications (DIVANet '19) (2019, November)

Over the recent years, Unmanned Aerial Vehicles' (UAVs) technology developed rapidly. In turn shedding light on a wide range of potential civil and commercial applications ranging from mapping and ... [more ▼]

Over the recent years, Unmanned Aerial Vehicles' (UAVs) technology developed rapidly. In turn shedding light on a wide range of potential civil and commercial applications ranging from mapping and surveillance, parcel delivery to more demanding ones that require UAVs to operate in heterogeneous swarms. However, with the great advantages UAVs bring, they are expected to soon dominate the shared, low-altitude airspace over populated cities, introducing multiple new research challenges in safely managing the unprecedented traffic demands. The main contribution of this work is addressing the complex problem of UAV traffic management at an abstract level by proposing a structure for the uncontrolled low-altitude airspace. The paper proposes a model of the airspace as a weighted multilayer network of nodes and airways and presents a set of experimental simulations of UAV traffic for the verification and validation of the model. Finally, the paper outlines our intended future work. [less ▲]

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See detailGraceful Interactions and Social Support as Motivational Design Strategies to Encourage Women in Exercising
Menheere, Daphne; Lallemand, Carine UL; Faber, Ilse et al

Scientific Conference (2019, November)

Increasingly aware of the importance of active lifestyles, many people intend to exercise more. Yet the main challenge remains to translate these intentions into action. Wearable devices supporting ... [more ▼]

Increasingly aware of the importance of active lifestyles, many people intend to exercise more. Yet the main challenge remains to translate these intentions into action. Wearable devices supporting exercise regrettably tend to adopt a one-size-fits-all approach by monitoring activity through quantified data as a motivation strategy. Since certain individuals are driven by social motives to exercise, less addressed through quantification, the impact of these devices on user experience and motivation is questionable. We contribute to the field by defining interaction attributes of graceful interactions in product design. We then embedded these in designing Grace, a piece of jewelry enabling women to share exercise intentions with friends to encourage social support. Instead of focusing on quantification, we rely on a qualitative approach using graceful interaction. Through this we extend the design space of sport-related wearables for women and inform how to design for exercise motivation through social support and graceful interactions. [less ▲]

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See detailPrivacy Aspects and Subliminal Channels in Zcash
Biryukov, Alex UL; Feher, Daniel UL; Vitto, Giuseppe UL

in Proceedings of the 2019 ACM SIGSAC Conference on Computer and Communications Securit (2019, November)

In this paper we analyze two privacy and security issues for the privacy-oriented cryptocurrency Zcash. First we study shielded transactions and show ways to fingerprint user transactions, including ... [more ▼]

In this paper we analyze two privacy and security issues for the privacy-oriented cryptocurrency Zcash. First we study shielded transactions and show ways to fingerprint user transactions, including active attacks.We introduce two new attacks which we call Danaan-gift attack and Dust attack. Following the recent Sapling update of Zcash protocol we study the interaction between the new and the old zk-SNARK protocols and the effects of their interaction on transaction privacy. In the second part of the paper we check for the presence of subliminal channels in the zk-SNARK protocol and in Pedersen Commitments. We show presence of efficient 70-bit channels which could be used for tagging of shielded transactions which would allow the attacker (malicious transaction verifier) to link transactions issued by a maliciously modified zk-SNARK prover, while would be indistinguishable from regular transactions for the honest verifier/user. We discuss countermeasures against both of these privacy issues. [less ▲]

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See detailCharacterization of the MSE Region under a Total Power Budget for Asynchronous Two-Way Relay Networks
Rahimi, Razgar; Shahbazpanahi, Shahram UL; Ottersten, Björn UL

in The Asilomar Conference on Signals, Systems, and Computers, Pacific Grove, CA, 3-6 November 2019 (2019, November)

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See detailA New Optimization Tool for Mega-Constellation Design and its Application to Trunking Systems
Kisseleff, Steven UL; Shankar, Bhavani UL; Spano, Danilo UL et al

in 37th International Communications Satellite Systems Conference (ICSSC), Japan, October 2019 (2019, November)

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See detailUser Terminal Wideband Modem for Very High Throughput Satellites
Kisseleff, Steven UL; Maturo, Nicola UL; Chatzinotas, Symeon UL et al

in 37th International Communications Satellite Systems Conference (ICSSC), Japan, October 2019 (2019, November)

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See detailVPGA: an SDN-based Location Privacy Zones Placement Scheme for Vehicular Networks
Boualouache, Abdelwahab UL; Soua, Ridha UL; Engel, Thomas UL

in 38th IEEE International Performance Computing and Communications Conference (IPCCC) (2019, October 29)

Making personal data anonymous is crucial to ensure the adoption of connected vehicles. One of the privacy-sensitive information is location, which once revealed can be used by adversaries to track ... [more ▼]

Making personal data anonymous is crucial to ensure the adoption of connected vehicles. One of the privacy-sensitive information is location, which once revealed can be used by adversaries to track drivers during their journey. Vehicular Location Privacy Zones (VLPZs) is a promising approach to ensure unlinkability. These logical zones can be easily deployed over roadside infrastructures (RIs) such as gas station or electric charging stations. However, the placement optimization problem of VLPZs is NP-hard and thus an efficient allocation of VLPZs to these RIs is needed to avoid their overload and the degradation of the QoS provided within theses RIs. This work considers the optimal placement of the VLPZs and proposes a genetic-based algorithm in a software defined vehicular network to ensure minimized trajectory cost of involved vehicles and hence less consumption of their pseudonyms. The analytical evaluation shows that the proposed approach is cost-efficient and ensures a shorter response time. [less ▲]

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See detailTeachers’ translanguaging stance, design, and shifts in a professional development course
Aleksic, Gabrijela UL; Bebic, Dzoen Dominique UL

Scientific Conference (2019, October 28)

Classrooms in Luxembourg are highly socially, culturally, and linguistically diverse. About 65% of 4 year-old children do not speak Luxembourgish, of which 28% speak Portuguese (MENJE, 2018). In 2017, the ... [more ▼]

Classrooms in Luxembourg are highly socially, culturally, and linguistically diverse. About 65% of 4 year-old children do not speak Luxembourgish, of which 28% speak Portuguese (MENJE, 2018). In 2017, the new law has declared multilingual early education mandatory. Until that time, the focus was solely on the development of Luxemburgish, whereas now teachers should also familiarize children with French and value their home languages. To support preschool teachers, our project aims to: (1) offer a professional development (PD) course in translanguaging, (2) involve children’s families to reinforce home-school collaboration, and (3) foster children’s cognitive, linguistic, and socio-emotional engagement in the classroom. We use focus groups, questionnaires, and language portraits with teachers and a test in early literacy and numeracy in school and home language and video observations with children. Translanguaging, the main topic of our 22 hour PD course (June – December 2019), is the use of a full linguistic repertoire to make meaning (Otheguy, García, & Reid, 2015). Through focus groups, we identified teachers’ negative translanguaging stance towards children’s proficiency in their home language that hinders the development of Luxembourgish. Translanguaging design was related to teachers’ use of multilingual stories and morning greetings, while translanguaging shifts concerned frequent translations by involving older children. Our main goal is to address the negative translanguaging stance by offering practical activities during the course and collaborating with parents, children, and organisational stakeholders. References Ministry of National Education, Childhood and Youth [MENJE]. (2018). Key numbers of the national education: statistics and indicators – School year 2016-2017. Retrieved from http://www.men.public.lu/fr/actualites/publications/themes-transversaux/statistiques-analyses/chiffres-cles/index.html Otheguy, R., García, O., & Reid, W. (2015). Clarifying translanguaging and deconstructing named languages: A perspective from linguistics. Applied Linguistic Review, 6(3), 281–307. [less ▲]

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See detailRebuilding the Office around the Mainframe: IBM’s S/360 in Context
van Herck, Sytze UL

Scientific Conference (2019, October 27)

The Oxford English Dictionary states that originally, a mainframe only defined the central processing unit and primary memory of a computer, whereas now a mainframe describes any large or general-purpose ... [more ▼]

The Oxford English Dictionary states that originally, a mainframe only defined the central processing unit and primary memory of a computer, whereas now a mainframe describes any large or general-purpose computer, specifically supporting numerous peripherals or subordinate computers. The IBM System/360, announced in 1964 and first installed at around 1967, consists of a collection of peripherals that can be connected to any central processing unit in the system family. Due to the size of both the individual components and the entire system, the design and layout of the office often needed to accommodate for the machine. Furthermore, “the experiences of weight, surface texture, sound and smell are part of the physicality of object” (Dannehl 2013, 130) so in order to experience the environment of a designated computer room, several museums have reconstructed at least some of the structure of a computer room. At the Living Computers Museum+Labs in Seattle the entrance to the separately airconditioned room is up a ramp, because of the raised floor that supports the weight of the computer and hides the very thick cables. Purchasing and installing an IBM System/360 required careful planning in terms of physical requirements and site selection, taking into account environmental, electrical, and signal factors. Besides the system and associated personnel, other furniture including storage cabinets, work tables, chairs, and desks also influenced planning. Furthermore, the length of the cables connecting the machines limited the distance between the system components. The schedule proposed by IBM encouraged customers to order six months before delivery and finalizing the layout two months later to allow for building alterations and time to process the cable order (IBM, 1975). Once the machine was installed, the dimensions and layout continuously influenced the workflow and working conditions of the users. Dannehl, Karin. 2013. “Object biographies. From production to consumption.” In History and Material Culture: A Student’s Guide to Approaching Alternative Sources, edited by Harvey, Karen, 123-138. Routledge. IBM System/360 Model 20 Installation Manual-Physical Planning. Systems Reference Library. Atlanta, Georgia: International Business Machines Corporation, 1975. Living Computers Museum+Labs, IBM, Box 1, 76027. [less ▲]

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See detailFacing parallel inventions: the French telecommunications strategies in the digital field (mid-1950s to mid-1990s)
Schafer, Valerie UL

Scientific Conference (2019, October 26)

This panel on parallel inventions is an opportunity to rethink 15-years of research on data networks and digitization from the perspective of simultaneity. The subject of parallel inventions in the field ... [more ▼]

This panel on parallel inventions is an opportunity to rethink 15-years of research on data networks and digitization from the perspective of simultaneity. The subject of parallel inventions in the field of data networks immediately brings to mind the outset of packet switching, a key concept of Arpanet and Internet (Bay, 2019) that was developed in the 1960s by several players, namely Paul Baran at the RAND Corporation, Leonard Kleinrock at UCLA and Donald Davies at the NPL (National Physical Laboratory) in Great Britain. Yet this Zeitgeist surrounding packet switching is not the only example of parallel ideas and projects within the history of data networks, nor is it limited to the US context. My presentation therefore aims to shift the focus to deepen our understanding of simultaneous inventions, turning away from the cumbersome examination of the “great figures” towards collective innovation and adoption. To do so, we will look at the telecommunications sector. Since the 1950s, this sector in the United States, France, Great Britain and other European countries has been confronted with computer needs and the challenge of building data networks based on their infrastructure – communication lines were mainly monopolized by telecommunication companies in Europe until the end of the 1980s. Several parallel paths were experimented during the period from the transition to electronic switching in phone equipment to the development of standards such as X25, which competed with Internet protocols in the 1980s and 1990s, demonstrating that innovation is not a linear process. Rather than discuss AT&T’s hostility towards packet switching as implemented in Arpanet, which has already been well documented (Abbate, 1999), this study will look at the French telecommunications administration and show how those responsible for the communication lines needed for French networks were positioning themselves to face the changes that had begun in the 1950s, whilst assessing parallel inventions that were either internal or external to the administration. Our paper will therefore focus less on invention per se than on the response to simultaneous inventions, and will review several simultaneous paths in the history of digital networks that French telecommunications had to face, and the associated process of collective decision-making. We will start by presenting the parallel development of spatial and temporal switching in the second half of the 1950s, then look at the simultaneous experiment of Caducée and Hermès networks (early 1970s). Complementary case studies will cover the debate about virtual circuits and datagrams from the 1970s to the 1990s, standardization within the field of telematics and the first Web offers in the transition period from the Minitel to the Web in the 1990s. Our analysis aims to establish a typology of the administration’s choices and attitudes, which differ according to whether the alternative is an internal solution or from an external source, but also according to the periods, from the telecommunications monopoly to the 1990s deregulation. In this way, we aim to reveal how inventions were not only connected to the technical context and knowledge, but were also shaped by those who were interested in the resulting technology. [less ▲]

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See detailThe Occupied Museum. Culture and Science in Luxemburg during the Nazi Occupation, 1940–1944
Spirinelli, Fabio UL

Scientific Conference (2019, October 24)

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See detailThe association between workplace bullying exposure and workplace bullying perpetration – The role of frustration of the need for relatedness
Sischka, Philipp UL; Steffgen, Georges UL

Scientific Conference (2019, October 24)

Workplace bullying (WB) is a serious phenomenon that has serious detrimental effects on victim’s health, attitudes, and work-related behavior (Nielsen & Einarsen, 2012). WB is seen as an escalated ... [more ▼]

Workplace bullying (WB) is a serious phenomenon that has serious detrimental effects on victim’s health, attitudes, and work-related behavior (Nielsen & Einarsen, 2012). WB is seen as an escalated conflict, where both parties engage in increasing overt acts of aggression (e.g., Einarsen et al., 2011). This perspective is supported by one of the most robust finding in WB and aggression literature, the association between experienced workplace aggression and enacting in workplace aggression (e.g., Baillien et al., 2016). However, there are only a few studies that have researched the mechanism between these phenomena (Samnani & Singh 2012). Self-determination theory (SDT) might explain this link. As need frustration is linked to less self-control (Vansteenkiste & Ryan, 2012), the frustration of the need for relatedness might also lead to increased aggressive behavior. Drawing on SDT, we propose that bullying exposure thwarts employee’s need for relatedness that increase aggressive behavior. Thus, the aim of our study was to test this mediation in a longitudinal design with short time intervals (i.e. monthly). A six-wave online survey design with monthly time lag was employed and data were collected among U.S. employees. The sample consists of 1,595 respondents (55.8% females, n=890, ageM = 36.9, ageSD =10.3). Workplace bullying exposure was assessed with the S-NAQ (Notelaers et al., 2018). Being a perpetrator of bullying was measured by the same nine items of the S-NAQ, however, formulated in an active manner (e.g., Baillien et al., 2011). Finally, frustration of the need for relatedness was assessed with the Psychological Needs Thwarting Scale (Bartholomew et al., 2011). Cross-lagged mediation analysis within a path modeling framework only partially confirmed the proposed model: WB exposure was significantly related to a change in frustration of relatedness. However, frustration of relatedness did (most of the time) not increase WB perpetration, but WB exposure. These longitudinal findings underline the vicious circle nature of WB exposure. [less ▲]

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See detailInformation Content of Systematic and Idiosyncratic Risk Disclosure
Weber, Véronique UL; Muessig, Anke UL

Scientific Conference (2019, October 24)

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See detailPrivacy-Preserving Processing of Filtered DNA Reads
Fernandes, Maria UL; Decouchant, Jérémie UL; Volp, Marcus UL et al

Scientific Conference (2019, October 22)

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See detailrom Text to Bits: Making the Treaties of a Monk from the 16th Century "Understandable" to the Computer
Dubuisson, Bastian UL

Scientific Conference (2019, October 19)

Historians who aspire to explore texts with the help of the computer are more than often confronted to the absence of machine-readable corpora to suit their needs. As such, the early 16th century Latin ... [more ▼]

Historians who aspire to explore texts with the help of the computer are more than often confronted to the absence of machine-readable corpora to suit their needs. As such, the early 16th century Latin treaties about the city of Trier and its relics by the Benedictine monk Johannes Scheckmann are no exception. Despite their historical importance, among others for the study of the religious phenomenon during this pivotal era, these texts remain in their original form. Optical Character Recognition software makes it possible to overcome this gap by translating printed or handwritten characters into encoded glyphs, but not at any cost. Creating a digital corpus requires a careful reflection, particularly when it comes to small scale projects. Moreover, Latin being a highly inflected language, further post-processing steps such as tokenization and lemmatization are necessary in order to finally be able to process a corpus of texts with lines of code. During the digital transformation, each step leads to a profound but necessary modification of the original text and the creation of new data. The example of Scheckmann’s works illustrates what is lost when a text is turned into bits, as well as what can be discovered once the machine reads. [less ▲]

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See detailSoftware Engineering for Dataset Augmentation using Generative Adversarial Networks
Jahic, Benjamin UL; Guelfi, Nicolas UL; Ries, Benoît UL

Scientific Conference (2019, October 19)

Software engineers require a large amount of data for building neural network-based software systems. The engineering of these data is often neglected, though, it is a critical and time-consuming activity ... [more ▼]

Software engineers require a large amount of data for building neural network-based software systems. The engineering of these data is often neglected, though, it is a critical and time-consuming activity. In this work, we present a novel software engineering approach for dataset augmentation using neural networks. We propose a rigorous process for generating synthetic data to improve the training of neural networks. Also, we demonstrate our approach to successfully improve the recognition of handwritten digits using conditional generative adversarial networks (cGAN). Finally, we shortly discuss selected important issues of our process, presenting related work and proposing some improvements. [less ▲]

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See detailRussische Immigration nach Luxemburg 1918-1935: Einwanderer aus einem nicht-existierenden Land
Ganschow, Inna UL

Scientific Conference (2019, October 18)

Die Einwanderer_innen aus dem früheren Russischen Reich trugen zur Arbeiterlandschaft im Süden, Norden und Osten Luxemburgs nach dem Ersten Weltkrieg bei. Nimmt man diese „Russen“ genauer unter die Lupe ... [more ▼]

Die Einwanderer_innen aus dem früheren Russischen Reich trugen zur Arbeiterlandschaft im Süden, Norden und Osten Luxemburgs nach dem Ersten Weltkrieg bei. Nimmt man diese „Russen“ genauer unter die Lupe, zeigen sich mindestens drei neue Gruppen, die die bereits vor 1914 bestehende russische Gemeinde vergrößerten. Die ersten sind die ehemaligen Kriegsgefangenen aus den Lagern in Frankreich, Belgien und Deutschland. Ein Teil ist vor Kriegsende als Flüchtlinge im Lande, die anderen kommen nach dem Waffenstillstand im November 1918. Sie wollen nicht zurück nach Russland, wo der Bürgerkriegt tobt. Die zweite Gruppe kommt im Laufe des Bürgerkrieges um 1926-1929 aus Bulgarien und Serbien nach. Es handelt sich um noch zusammenhaltende Weißgardisten, die zu der über die Krim in die Türkei evakuierte Armee von Petr Wrangel gehörten. Schließlich ist die dritte Gruppe der zivilen politischen Flüchtlinge zu erwähnen, die seit den frühen 1920ern meistens über Deutschland nach Luxemburg kamen und öfters Angehörigen der jüdischen Glaubensgemeinschaft waren. Viele von ihnen sind bereits seit den intensivierten Pogromen der ersten russischen Revolution von 1905 in Europa. Die Wanderungsstrukturen dieser verschiedenen und sehr heterogenen Gruppen von „Russen“ stehen im Mittelpunkt des Vortrags. [less ▲]

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See detailDiscussion of "Do ETFs Increase Liquidity?" by Mehmet Saglam, Tugkan Tuzun and Russ Wermers
Holcblat, Benjamin UL

Scientific Conference (2019, October 18)

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See detailApproche européenne sur l'entreprise : de la nouveauté ?
Corbisier, Isabelle UL

Scientific Conference (2019, October 17)

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See detailMonitoring du système scolaire – Le modèle luxembourgeois (invited talk)
Fischbach, Antoine UL

Scientific Conference (2019, October 17)

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See detailRegards allemands sur le Luxembourg
Brüll, Christoph UL

Scientific Conference (2019, October 17)

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See detailRegards belges sur le Luxembourg 1919-1921
Brüll, Christoph UL

Scientific Conference (2019, October 17)

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See detailOral History Choices in the Digital Age: An International Perspective
Lambert, Douglas UL

Scientific Conference (2019, October 17)

Indexing oral histories digitally at the timecode level is a practice increasingly adopted for collections, often with the goal of creating online access to recordings. A particular attraction to using an ... [more ▼]

Indexing oral histories digitally at the timecode level is a practice increasingly adopted for collections, often with the goal of creating online access to recordings. A particular attraction to using an index is that it can be generated in less time than a transcript, especially when both must be done manually. Indexing provides convenient access to original recordings and can be a platform for decision-making about a collection over time, for researchers or collection stewards. In my current work in digital oral history at the University of Luxembourg’s Centre for Contemporary and Digital History (C2DH), indexing is being embraced for these strategic and practical benefits. However, indexing approaches I promoted previously in the US will need to be re-envisioned, retooled, and otherwise adapted for new and different cultural and technological contexts. In Europe, many oral history projects tend to be focused on journalistic-style research, so the goal of recording and indexing is different; curating, archiving, and publishing recordings is not necessarily expected or assumed. In Luxembourg and elsewhere in Europe, there is great interest in applying technology-centered analyses to oral history corpora (e.g., topic modeling, sentiment analysis, corpus linguistics, etc.), work predicated on high-quality transcripts rather than indexing. At the same time, improvements have been made in other technology/transcript-centered methods of analysis, such as keyword extraction, named entity recognition, and automated indexing—all of which could advance and improve oral history indexing and analysis practice. These new approaches will be more viable as speech recognition technology continues to improve, making transcripts easier and cheaper to create. As these factors converge, a new balance between transcription, indexing, and human interpretation will develop that supports both conventional oral history uses as well as secondary collection research activities. [less ▲]

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See detailOuter and Anti Joins in Temporal-Probabilistic Databases
Papaioannou, Katerina; Theobald, Martin UL; Böhlen, Michael H.

in 35th IEEE International Conference on Data Engineering, ICDE 2019, Macao, China, April 8-11, 2019 (2019, October 16)

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See detailTravail frontalier en Suisse et au Luxembourg : mobilités, profils et défis
Pigeron-Piroth, Isabelle UL; Helfer, Malte UL; Belkacem, Rachid

Scientific Conference (2019, October 15)

La Suisse et le Luxembourg sont particulièrement concernés par le travail frontalier. Ces deux pays accueillent à eux seuls plus d’un demi-million de travailleurs frontaliers et recourent à la main ... [more ▼]

La Suisse et le Luxembourg sont particulièrement concernés par le travail frontalier. Ces deux pays accueillent à eux seuls plus d’un demi-million de travailleurs frontaliers et recourent à la main-d’œuvre frontalière depuis plusieurs décennies. Petits pays dynamiques ayant d’importants besoins de main-d’œuvre, ils se caractérisent par des différentiels liés à la présence de frontières (différentiels de prix immobiliers, de taux de chômage, de salaires, de niveaux d’activité économique … avec les pays voisins). Ces différentiels entretiennent la dynamique du travail frontalier (Belkacem et Pigeron-Piroth, 2016). [less ▲]

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See detailInside the Trading Zone: Doing Digital Hermeneutics in an Interdisciplinary Setting
van der Heijden, Tim UL; Tatarinov, Juliane UL

Scientific Conference (2019, October 11)

Our contribution examines the conference theme of digital hermeneutics from the perspective of the Doctoral Training Unit (DTU) in ‘Digital History and Hermeneutics’, a four-year interdisciplinary ... [more ▼]

Our contribution examines the conference theme of digital hermeneutics from the perspective of the Doctoral Training Unit (DTU) in ‘Digital History and Hermeneutics’, a four-year interdisciplinary research and training program hosted by the Centre for Contemporary and Digital History (C²DH) at the University of Luxembourg. The DTU is designed as an experimental platform for collaboration or ‘trading zone’, in which thirteen doctoral candidates with different disciplinary backgrounds – from history, linguistics and philosophy to computer and information science – study and reflect on the epistemological and methodological implications of the ‘digital turn’ on historical research. This presentation reflects on the project’s first year, in which the doctoral candidates were introduced to various skills and methods in digital humanities, including text mining, digital source criticism, database structures, data visualization, GIS analysis, tool criticism and algorithmic critique; and its second year, when data collections had been created and research tools identified that were going to be applied to it. By doing so, it presents some of the main practical and epistemological opportunities and challenges of “thinkering” with digital tools and technologies in the Digital History Lab of the C2DH, and it reflects scientific dissemination strategies for the group and the individual. The analysis is informed by studies on interdisciplinarity, digital humanities infrastructures and communities of practice. It furthermore draws on a series of semi-structured interviews and self-reflexive training reports, in which the doctoral candidates of the DTU reflect on their experiences in doing digital hermeneutics in an interdisciplinary setting. [less ▲]

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See detailDeep Learning Quality Control for High-Throughput High-Content Screening Microscopy Images
Garcia Santa Cruz, Beatriz UL; Jarazo, Javier UL; Schwamborn, Jens Christian UL et al

Poster (2019, October 10)

Automation of biological image analysis is essential to boost biomedical research. The study of complex diseases such as neurodegenerative diseases calls for big amounts of data to build models towards ... [more ▼]

Automation of biological image analysis is essential to boost biomedical research. The study of complex diseases such as neurodegenerative diseases calls for big amounts of data to build models towards precision medicine. Such data acquisition is feasible in the context of high-throughput high-content screening (HTHCS) in which the quality of the results relays on the accuracy of image analysis. Deep learning (DL) yields great performance in image analysis tasks especially with big amounts of data such as the produced in HTHCS contexts. Such DL and HTHCS strength is also their biggest weakness since DL solutions are highly sensitive to bad quality datasets. Hence, accurate Quality Control (QC) for microscopy HTHCS becomes an essential step to obtain reliable pipelines for HTHCS analysis. Usually, artifacts found on these platforms are the consequence of out-of-focus and undesirable density variations. The importance of accurate outlier detection becomes essential for both the training process of generic ML solutions (i.e. segmentation or classification) and the QC of the input data such solution will predict on. Moreover, during the QC of the input dataset, we aim not only to discard unsuitable images but to report the user on the quality of its dataset giving the user the choice to keep or discard the bad images. To build the QC solution we employed fluorescent microscopy images of rosella biosensor generated in the HTHCS platform. A total of 15 planes ranging from -6z to +7z steps to the two optimum planes. We evaluated 27 known focus measure operators and concluded that they have low sensitivity in noisy conditions. We propose a CNN solution which predicts the focus error based on the distance to the optimal plane, outperforming the evaluated focus operators. This QC allows for better results in cell segmentation models based on U-Net architecture as well as promising improvements in image classification tasks. [less ▲]

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See detailThe ESP estimator
Holcblat, Benjamin UL; Sowell, Fallaw

Scientific Conference (2019, October 08)

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See detailBig Automotive Data Preprocessing: A Three Stages Approach
Tawakuli, Amal UL; Kaiser, Daniel UL; Engel, Thomas UL

Poster (2019, October 08)

The automotive industry generates large datasets of various formats, uncertainties and frequencies. To exploit Automotive Big Data, the data needs to be connected, fused and preprocessed to quality ... [more ▼]

The automotive industry generates large datasets of various formats, uncertainties and frequencies. To exploit Automotive Big Data, the data needs to be connected, fused and preprocessed to quality datasets before being used for production and business processes. Data preprocessing tasks are typically expensive, tightly coupled with their intended AI algorithms and are done manually by domain experts. Hence there is a need to automate data preprocessing to seamlessly generate cleaner data. We intend to introduce a generic data preprocessing framework that handles vehicle-to-everything (V2X) data streams and dynamic updates. We intend to decentralize and automate data preprocessing by leveraging edge computing with the objective of progressively improving the quality of the dataflow within edge components (vehicles) and onto the cloud. [less ▲]

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