Last 7 days
Bookmark and Share    
Full Text
Peer Reviewed
See detailArtificial intelligence and machine learning: an introduction for orthopaedic surgeons
Ley, Christophe UL; Martin, R. Kyle; Pareek, Ayoosh et al

in Knee Surgery, Sports Traumatology, Arthroscopy (2021)

The application of artificial intelligence (AI) and machine learning to the field of orthopaedic surgery is rapidly increasing. While this represents an important step in the advancement of our specialty ... [more ▼]

The application of artificial intelligence (AI) and machine learning to the field of orthopaedic surgery is rapidly increasing. While this represents an important step in the advancement of our specialty, the concept of AI is rich with statistical jargon and techniques unfamiliar to many clinicians. This knowledge gap may limit the impact and potential of these novel techniques. We aim to narrow this gap in a way that is accessible for all orthopaedic surgeons. With this manuscript, we introduce the concept of AI and machine learning and give examples of how it can impact clinical practice and patient care. [less ▲]

Detailed reference viewed: 10 (0 UL)
Full Text
See detailHarnessing the Exposome, Cheminformatics and Mass Spectrometry for Clinical Metabolomics
Schymanski, Emma UL

Scientific Conference (2021, September 14)

Detailed reference viewed: 18 (0 UL)
Full Text
Peer Reviewed
See detailJoint Transmit Waveform and Receive Filter Design for Dual-Function Radar-Communication Systems
Tsinos, Christos UL; Arora, Aakash UL; Chatzinotas, Symeon UL et al

in IEEE Journal of Selected Topics in Signal Processing (2021), 15(6), 1378-1392

In this paper, the problem of joint transmit waveform and receive filter design for dual-function radar-communication (DFRC) systems is studied. The considered system model involves a multiple antenna ... [more ▼]

In this paper, the problem of joint transmit waveform and receive filter design for dual-function radar-communication (DFRC) systems is studied. The considered system model involves a multiple antenna base station (BS) of a cellular system serving multiple single antenna users on the downlink. Furthermore, the BS simultaneously introduces sensing capabilities in the form of point-like target detection from the reflected return signals in a signal-dependent interference environment. A novel framework based on constrained optimization problems is proposed for the joint design of the transmit waveform and the radar receive filter such that different constraints related to the power amplifiers and the radar waveform are satisfied. In contrast to the existing approaches in the DFRC systems’ literature, the proposed approach does not require the knowledge of a predetermined radar beampattern in order to optimize the performance of the radar part through its approximation. Instead, a beampattern is generated by maximizing the radar receive signal-to-interference ratio (SINR) thus, enabling a more flexible design. Moreover, the radar receive filter processing and its optimization is considered for the first time on DFRC systems, enabling the effective exploitation of the available degrees of freedom in the radar receive array. Efficient algorithmic solutions with guaranteed convergence are developed for the defined constrained nonconvex optimization problems. The effectiveness of the proposed solutions is verified via numerical results. [less ▲]

Detailed reference viewed: 35 (4 UL)
Full Text
See detailUpdate on NORMAN-SusDat NORMAN-SLE (Suspect List Exchange)
Schymanski, Emma UL

Scientific Conference (2021, September 14)

Detailed reference viewed: 22 (0 UL)
Full Text
Peer Reviewed
See detailChild–Computer Interaction: From a systematic review towards an integrated understanding of interaction design methods for children
Lehnert, Florence Kristin UL; Niess, Jasmin; Lallemand, Carine UL et al

in International Journal of Child - Computer Interaction (2021), 100398

Child–Computer Interaction (CCI) is a steadily growing field that focuses on children as a prominent and emergent user group. For more than twenty years, the Interaction Design for Children (IDC ... [more ▼]

Child–Computer Interaction (CCI) is a steadily growing field that focuses on children as a prominent and emergent user group. For more than twenty years, the Interaction Design for Children (IDC) community has developed, extended, and advanced research and design methods for children’s involvement in designing and evaluating interactive technologies. However, as the CCI field evolves, the need arises for an integrated understanding of interaction design methods currently applied. To that end, we analyzed 272 full papers across a selection of journals and conference venues from 2005 to 2020. Our review contributes to the literature on this topic by (1) examining a holistic child population, including developmentally diverse children and children from 0 to 18 years old, (2) illustrating the interplay of children’s and adults’ roles across different methods, and (3) identifying patterns of triangulation in the methods applied while taking recent ethical debates about children’s involvement in design into account. While we found that most studies were conducted in natural settings, we observed a preference for evaluating interactive artifacts at a single point in time. Method triangulation was applied in two-thirds of the papers, with a preference for qualitative methods. Researchers used triangulation predominantly with respect to mainstream methods that were not specifically developed for child participants, such as user observation combined with semi-structured interviews or activity logging. However, the CCI field employs a wide variety of creative design methods which engage children more actively in the design process by having them take on roles such as informant and design partner. In turn, we see that more passive children’s roles, e.g., user or tester, are more often linked to an expert mindset by the adult. Adults take on a wider spectrum of roles in the design process when addressing specific developmental groups, such as children with autism spectrum disorder. We conclude with a critical discussion about the constraints involved in conducting CCI research and discuss implications that can inform future methodological advances in the field and underlying challenges. [less ▲]

Detailed reference viewed: 58 (8 UL)
Full Text
Peer Reviewed
See detailMachine learning for surgical time prediction
Martinez, Oscar; Martinez Luna, Carol UL; Parra, Carlos et al

in Computer Methods and Programs in Biomedicine (2021)

Detailed reference viewed: 42 (1 UL)
Full Text
See detailStructuration of piezotronic junctions for ultrasensitive strain sensors
Joly, Raoul Joseph Adolphe UL

Doctoral thesis (2021)

The piezotronic effect relies on the creation of piezoelectric polarization charges mechanically induced within a piezoelectric semiconductor to modulate the carrier dynamics across electronic contact ... [more ▼]

The piezotronic effect relies on the creation of piezoelectric polarization charges mechanically induced within a piezoelectric semiconductor to modulate the carrier dynamics across electronic contact interfaces. The field of piezotronics is a relatively new area of study, based on a mechanical signal triggering, which is one of the most common kind of interactions between the environment and electronic systems. It started to draw a considerable attention in the early 2010’s, by reaching higher electromechanical sensitivities when compared to conventional methods of sensing. The rapidly spreading Internet-of-Things is accelerating Micro-ElectroMechanical Systems (MEMS) industry to deliver highly sensitive and miniaturized self-sensing sensors with low power consumption and cost-effective production process. Within this context, strain sensors based on the piezotronic effect appear as promising candidates to address these needs. However, several crucial questions remain unanswered or need to be refined, concerning the design and integration of piezotronic junctions with its fabrication process into microsystems or MEMS, the optimal configuration for strain sensing as well as noise studies for such systems. This PhD thesis proposes to rationalize the piezotronic effect for strain sensors and presents a novel microfabrication process integrating for the first time piezotronic strain sensors in millimetre-sized cantilevers on flexible polymeric substrates by means of maskless laser lithography. The atomic layer deposition (ALD) technique was used for the deposition of ZnO polycrystalline thin films on high work function metals to obtain Schottky junctions. However, such ZnO-based Schottky junctions by ALD have never been post-processed and integrated into a strain sensor. We propose to rationalize the ALD processing to obtain wurtzite polycrystalline zinc oxide thin films with a privileged (002) orientation and to make it compatible with microfabrication processing on polymer. The difficulties linked with the integration of inorganic thin films onto a polymeric substrate within the developed microfabrication process will be highlighted. We propose appropriate adjustments of the sensor’s design and the process flow. Pt/ZnO/Pt back-to-back Schottky diode junctions have been shaped in interdigitated microelectrodes to get piezotronic strain sensing on the clamp area of the cantilever structure. The conduction mechanisms occurring within the piezotronic strain microsensors have been thoroughly studied, based on the thermionic emission model. The developed electrical model will be detailed, emphasizing the presence of interface trap states and their prominent impact on the electrical characteristics. The piezotronic strain sensors’ transducing properties will be detailed as well by the mean of force spectroscopy, leading to the expected Schottky barrier height modulation by the piezotronic effect. Furthermore, we investigated for the first time the noise figure of within strain sensors based on the piezotronic effect. These new insights about noise amplitudes and origins are promising matter of optimization to improve the signal-to-noise ratio of the sensor. Within the last section of this work, we will detail the piezotronic strain sensors size miniaturization for integration in microcantilevers in a full-SU8 body. The miniaturization of our strain sensors makes them more prone for AFM (Atomic Force Microscopy) scanning probe operations on commercial machines, with the aim of greatly improving the sensitivity to small mechanical deformations. The approach taken for the microfabrication of these miniaturized sensors is based on a reversed processing by the mean of a sacrificial layer. This raised new difficulties in terms of metal adhesion and electrical contact continuity, which will be reported. The results obtained are highly promising and pave the way towards the processing of ultrasensitive strain microsensors on MEMS structures, as well as their great potential for AFM scanning probe operations. [less ▲]

Detailed reference viewed: 80 (0 UL)
Full Text
See detailThree Essays on the Role of Institutions in Labor Market Polarization
Pettinger, Maxime Dominique Eric UL

Doctoral thesis (2021)

This dissertation examines the impact of institutions on the distribution of jobs and wages, with a special focus on European countries. We are more specifically interested in labor market polarization, a ... [more ▼]

This dissertation examines the impact of institutions on the distribution of jobs and wages, with a special focus on European countries. We are more specifically interested in labor market polarization, a phenomenon which has notably been observed in the US between the 1980s and the 2010s. While wage polarization describes an increase in wages at both ends of the distribution relative to the middle, job polarization refers to an increase in the employment share of both low- and high-skill jobs relative to middle-skill jobs. A now standard explanation of this phenomenon is routine-biased technical change (RBTC). According to this approach, technical progress favors the substitution of machines --- and, indirectly, of high-skill workers --- for middle-skill labor, which leads in fine to the polarization of the distribution of earnings and jobs. While labor market polarization has also been observed in Europe, the intensity of this phenomenon depends on the country considered. Since developed economies have a similar access to technology, other determinants of the distribution of jobs and wages have to be considered to explain these cross-country differences. This dissertation considers institutions and demonstrates that a highly institutionalized labor market mitigates the twofold phenomenon of polarization. Institutions --- which are typically country-specific --- can thus partially explain cross-country differences in labor market polarization. This dissertation consists of three essays. In the first essay, we implement decomposition methods to show the impact of institutions on the wage structure. Our strategy makes use of the difference between the public and the private sector in terms of institutionalization of the wage-setting process. Decomposing the change in wage quantiles for both sectors and operating a between-sector comparison of the results for a set of European countries, we reach the conclusion that institutions are able to mitigate the RBTC-induced polarization of the wage structure. In the second essay, we develop a theoretical model based on the Acemoglu and Autor (2011) task-based framework. We contribute to this framework by including, in a Ricardian model of the labor market à la Acemoglu and Autor, an institutional device which mitigates wage polarization, based on the results of the first essay of this dissertation. While this device can be thought as unions operating in a centralized and coordinated bargaining regime, it is not restricted to this interpretation. Our model predicts that the institutions we consider, by mitigating wage polarization, have an anti-polarizing impact on the change in employment: while job polarization still follows skill-biased technical change, it is less pronounced in a highly institutionalized labor market. In the third and last essay, we test the predictions of the model presented in the second essay by empirically assessing the impact of institutions on job polarization. For each country studied in the first essay and for each year of the period 1992-2017, we build a measure of job polarization, based on the employment levels observed in selected, ranked and aggregated occupational categories. We then build a composite index of institutionalization and use panel cointegration techniques to estimate the long-run relationship between this index and each component of job polarization. Finally, we take into account both the reverse-causality problem implied by such a study and the potential delayed response of the variables by resorting on panel vector autoregressive models and structural impulse response analysis. Our results indicate that de-institutionalization fosters both components of job polarization, confirming the structural interpretation of the model introduced in the second essay. By combining different approaches and methods, this dissertation thus shows that the impact of technical change on the wage and occupational structure is mediated by country-specific institutional settings. Institutions do have an impact on labor market polarization, and can clearly be used to foster or inhibit this phenomenon. [less ▲]

Detailed reference viewed: 70 (11 UL)
Full Text
See detailIdentifying Exposome Chemicals: Measured Data Metadata, Metabolism and More …
Schymanski, Emma UL

Scientific Conference (2021, September 10)

Detailed reference viewed: 21 (0 UL)
Full Text
Peer Reviewed
See detailWie beeinflusst die soziale Herkunft Studienverläufe von Bachelorstudierenden in Deutschland?
Haas, Christina UL

in Blättel-Mink, Birgit (Ed.) Gesellschaft unter Spannung. Verhandlungen des 40. Kongresses der Deutschen Gesellschaft für Soziologie 2020 (2021, September 09)

Im Beitrag wird untersucht, wie die soziale Herkunft Verläufe von Studierenden durch das Bachelorstudium beeinflusst. Während bereits gezeigt wurde, dass sich Schulabgänger/-innen unterschiedlicher ... [more ▼]

Im Beitrag wird untersucht, wie die soziale Herkunft Verläufe von Studierenden durch das Bachelorstudium beeinflusst. Während bereits gezeigt wurde, dass sich Schulabgänger/-innen unterschiedlicher sozialer Herkunftsgruppen in ihrer Studieneintrittswahrscheinlichkeit unterscheiden und ob sie nach dem Bachelorstudium ein Masterstudium aufnehmen, gibt es weniger Forschung zum Zusammenhang zwischen der sozialen Herkunft und der Gestaltung des Studienverlaufs zwischen Ersteinschreibung und Studienabschluss bzw. -abbruch. Der Beitrag rekonstruiert auf Basis der Studierendenkohorte des Nationalen Bildungspanels Verläufe von Studierenden, die sich im Wintersemester 2010 für ein Bachelorstudium an deutschen Universitäten eingeschrieben haben, mittels Sequenzmusteranalyse. Diese Methode erfasst den gesamten Studienverlauf und ermöglicht es, die Studiendauer, Studienabbrüche, -abschlüsse, Fachwechsel und ferner Unterbrechungen zu berücksichtigen. Der soziale Hintergrund der Studierenden wird als mehrdimensionales Konzept verstanden. Dabei werden im Beitrag die elterliche Bildung sowie der berufliche Status berücksichtigt, die mit der Bereitstellung kultureller und ökonomischer Ressourcen verknüpft sind. Die Ergebnisse der Sequenzmusteranalyse und der anschließenden Clusteranalyse verweisen auf sechs Studienverlaufstypen, die unterschiedlich häufig in der Studierendenpopulation vorzufinden sind. Insgesamt deuten die Ergebnisse der multinomialen logistischen Regression vor allem auf eine Benachteiligung von Studierenden aus niedrig gebildeten Elternhäusern hin: im Gegensatz zu Studierenden aus akademischen Elternhäusern weisen diese häufiger komplexe und nicht abgeschlossene Studienverläufe auf. Ähnliches gilt im Hinblick auf den beruflichen Status des Elternhauses. [less ▲]

Detailed reference viewed: 45 (0 UL)
Full Text
Peer Reviewed
See detailFirst steps into developing multilingual practices in ECEC in Luxembourg: Insights from the projects MuLiPEC and COMPARE
Kirsch, Claudine UL

Scientific Conference (2021, September 07)

Translanguaging pedagogies promise to take account of students’ language and socio-cultural backgrounds and contribute to their academic achievements (García, Johnson, and Seltzer, 2017). Researchers who ... [more ▼]

Translanguaging pedagogies promise to take account of students’ language and socio-cultural backgrounds and contribute to their academic achievements (García, Johnson, and Seltzer, 2017). Researchers who have investigated translanguaging practices in monolingual, bilingual and multilingual contexts, have shown that translanguaging promotes learning, well-being, and identity-building (Lewis, Jones, and Baker, 2012; García & Sylvan, 2011; Young & Mary, 2016; Vaish 2019a). Studies in early childhood education and care (ECEC) remain scarce, particularly those that focus on the use of institutional languages and home languages. Furthermore, little is known about the implementation of translanguaging pedagogies and the challenges faced by professionals. One exception comes from Vaish (2019 a, b) who investigated the practices of primary teachers in Singapore who taught in English, Chinese and Malay. She identified three main challenges: superdiversity, negative attitudes towards home language, and teacher-centred pedagogies. Studies on professional development (PD) in ECEC have shown that PD can help practitioners change beliefs, knowledge and practices to some extent (Egert et al. 2018). This presentation comes from multilingual Luxembourg, where 63.7% of the 4-year-olds do not speak Luxembourgish as their home language. Since 2017, educators in ECEC are required to develop children’s skills in Luxembourgish, familiarise them with French and value their home languages. Professional development courses help practitioners move away from monolingual policies and practices that existed prior to 2017, and implement multilingual pedagogies. This paper examines the challenges teachers and educators faced during this process. It is based on seven group interviews carried out during two research projects; the first aimed to develop multilingual pedagogies (MuLiPEC), the second collaboration with parents and multiliteracies (COMPARE). The findings, based on thematic analysis, indicate, firstly, that the educators faced multiple challenges when trying to change their practices such as their uncertainty of how to deal with multiliteracy, their behaviourist views on education, their inexperience of planning literacy activities in multiple languages, and, secondly, the ways in which they overcame them. The PD courses helped them reflect on their beliefs, challenge monolingual ideologies, and develop knowledge about language learning and new multilingual practices (Kirsch 2020). The findings shed light on the complexities of the implementation process and the support needed for professional learning. [less ▲]

Detailed reference viewed: 36 (0 UL)
Full Text
Peer Reviewed
See detailEvaluating a location-based game to support citizens' situated reflection on history: a mixed-method approach
Jones, Catherine UL

in International Journal of Cartography (2021), 7

This paper describes the process and findings of a critical evaluation conducted for a custom-made Location based game (LBG) designed to support reflection on social history. We use a mixed-method ... [more ▼]

This paper describes the process and findings of a critical evaluation conducted for a custom-made Location based game (LBG) designed to support reflection on social history. We use a mixed-method protocol to answer the following research questions: “Can a LBG be designed to stimulate situated reflection on social history topics? and “What form and type of reflections can occur when participating in a LBG? Using an innovative approach that took inspiration from the field of museum studies and computer science. We chose a Think-aloud protocol to conduct an evaluation in Valletta, Malta and adapted the Remind study protocol to explore participant experience in Luxembourg. We combined transcripts from both sets of experiments wiith user-generated content to complete a systematic analysis using a predefined set of qualitative codes. We were able to identify that LBG can support reflection on social history topics but the depth of and type of reflection depends on the social history content, the individual locations in the city, and personal connections players are able to make to both. [less ▲]

Detailed reference viewed: 30 (1 UL)
Peer Reviewed
See detailPerspectives on multilingualism and multilingual literacies from early childhood educators in Luxembourg
Kirsch, Claudine UL; Aleksic, Gabrijela UL; Bebić, Džoen Dominique UL et al

Scientific Conference (2021, September 04)

The pedagogies of multiliteracies and translanguaging (García et al., 2017) call for multiliteracies, but early childhood educators are often ensure of how to develop practices in one, let alone multiple ... [more ▼]

The pedagogies of multiliteracies and translanguaging (García et al., 2017) call for multiliteracies, but early childhood educators are often ensure of how to develop practices in one, let alone multiple languages. The development of literacy skills is often reduced to the isolated training of phonological awareness or the letters of the alphabet. By contrast, storytelling is a holistic approach which contributes to the development of language and literacy skills (Sénéchal & Lefevre, 2001). It can promote multilingualism if multilingual speakers are involved (Kirsch, 2018). This presentation reports on the perspectives on multiliteracies of educators in crèches in multilingual Luxembourg, where 63.7% of the 4-year-olds do not speak Luxembourgish at home. Multilingual education became mandatory in 2017, requesting educators to develop Luxembourgish, promote French and value home languages. The mix-method project Collaboration with parents and Multiliteracy in early Childhood Education aims to develop literacy practices in multiple languages and with multiple actors (parents, educators) through professional development in crèches. In this paper we report the findings of interviews and a survey sent to 700 educators in May 2020. The latter were asked to identify literacy practices (e.g. storytelling), language-promoting strategies, and translanguaging practices. The data are analysed with thematic analysis and descriptive statistical analysis. The findings will contribute to our understanding of current ideologies, pedagogies, and practices, and help identify issues and possible ways forward. [less ▲]

Detailed reference viewed: 71 (8 UL)
Full Text
See detailThe Decline of Repair Businesses? Luxembourg’s Repair Sector, 1971–1985
Krebs, Stefan UL; Hoppenheit, Thomas UL

Scientific Conference (2021, September 03)

Detailed reference viewed: 42 (3 UL)
Peer Reviewed
See detailValues-Based Territorial Food Networks (VTFN): conceptual framework spanning Local Food Systems (LFS), Short Food Supply Chains (SFSC), Civic Food Networks (CFN) and Alternative Food Networks (AFN)
Reckinger, Rachel UL

Scientific Conference (2021, September 02)

Localized food growing and livestock rearing initiatives with more direct transformation and commercialization structures, often at comparably small scales, gained ground worldwide. They represent various ... [more ▼]

Localized food growing and livestock rearing initiatives with more direct transformation and commercialization structures, often at comparably small scales, gained ground worldwide. They represent various types of ‘alternatives’ to industrialised agri-food processes and to standard producers/consumers divides characterizing the global food system. While these alternatives are not always new, they have sparked growing scholarly interest. Over time, the literature has addressed them via four main conceptual denominations: Local Food Systems (LFS), Short Food Supply Chains (SFSCs), Civic Food Networks (CFS), Alternative Food Networks (AFN). These concepts have distinct foci, partial overlaps, and they seek to capture an immense heterogeneity of empirical phenomena. Yet this conceptual plurality risks to conceal that these empirical initiatives, despite their differences, have structural commonalities at food system level, relevant for understanding pathways to a sustainable food system transformation. Therefore, I argue for an overarching concept subsuming the existing ones. Values-based Territorial Food Networks (VTFN) would take into account the diverse perspectives from the four main concepts in this field, classify their specificities and address their shortcomings. The social critique at their core, leading to transitions, is constructed around values of ’doing things differently’, at the level of specific territories. The more robust and authentic these sustainability values in VTFN are – in terms of environmental integrity, social well-being, economic resilience and ethical governance – the more likely they are to be incorporated into practices, to become more and more legitimate and gain a voice at negotiation tables, in order to help reorient the current corporate agrifood regime. [less ▲]

Detailed reference viewed: 45 (2 UL)