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See detailOptinization of wireless energy transfer for mid-range distances
Ripp, Pascal UL

Doctoral thesis (2017)

This thesis deals with the optimization of resonators for wireless power transfer by resonant magnetic coupling, where loosely coupled LC resonators are used for wireless power transmission. While systems ... [more ▼]

This thesis deals with the optimization of resonators for wireless power transfer by resonant magnetic coupling, where loosely coupled LC resonators are used for wireless power transmission. While systems that are currently available use discrete capacitors for frequency tuning, this work proposes self-resonating coils on a printed circuit board. For these coils, different three-dimensional (3D) Computer Aided Design (CAD) models are created and investigated using the method of finite elements. Finally, a set of inductively coupled and capacitively coupled self-resonant coils for the 6.78 MHz ISM band is found. Furthermore, the shielding of the coils with ferrite materials is discussed to maintain a high efficiency for any application. For both types, equivalent circuit models are derived and analyzed. Besides the coil optimization, a power amplifier is also proposed. During operation the optimal operational frequency is maintained by frequency tracking. The theoretical results are verified using a demonstrator circuit. [less ▲]

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See detailCorporate Ownership Structure and the Cash Flow Sensitivity of Cash
Derouiche, Imen UL; Saffar, Walid; Boubaker, Sabri

Scientific Conference (2017, April 01)

This article examines the effects of excess control rights of the controlling shareholder and the presence of multiple large shareholders on financial constraints, proxied by cash flow sensitivity of cash ... [more ▼]

This article examines the effects of excess control rights of the controlling shareholder and the presence of multiple large shareholders on financial constraints, proxied by cash flow sensitivity of cash. Using a unique data set of 745 French listed firms during 1998—2013, the results show that firms have high cash flow sensitivity of cash when the controlling shareholder’s control rights exceed its cash-flow ownership. This sensitivity decreases, however, with the contestability of the controlling owner’s power. Taken together, these findings provide empirical support to the argument that firms experiencing excess control rights face considerable financial constraints that are lowered in the presence of high control contestability. [less ▲]

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See detailDiscrete-Event Simulation and Integer Linear Programming for Constraint-Aware Resource Scheduling
Shin, Seung Yeob UL; Brun, Yuriy; Balasubramanian, Hari et al

in IEEE Transactions on Systems, Man, and Cybernetics: Systems (2017)

This paper presents a method for scheduling resources in complex systems that integrate humans with diverse hardware and software components, and for studying the impact of resource schedules on system ... [more ▼]

This paper presents a method for scheduling resources in complex systems that integrate humans with diverse hardware and software components, and for studying the impact of resource schedules on system characteristics. The method uses discrete-event simulation and integer linear programming, and relies on detailed models of the system’s processes, specifications of the capabilities of the system’s resources, and constraints on the operations of the system and its resources. As a case study, we examine processes involved in the operation of a hospital emergency department, studying the impact staffing policies have on such key quality measures as patient length of stay (LoS), number of handoffs, staff utilization levels, and cost. Our results suggest that physician and nurse utilization levels for clinical tasks of 70% result in a good balance between LoS and cost. Allowing shift lengths to vary and shifts to overlap increases scheduling flexibility. Clinical experts provided face validation of our results. Our approach improves on the state of the art by enabling using detailed resource and constraint specifications effectively to support analysis and decision making about complex processes in domains that currently rely largely on trial and error and other ad hoc methods. [less ▲]

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See detailPopulation ageing [glossary]
Chiocchetti, Paolo UL

E-print/Working paper (2017)

Population ageing is a major trend in contemporary European societies. A consequence of welcome shifts in life expectancy and fertility, it nevertheless entails important challenges for the adequacy ... [more ▼]

Population ageing is a major trend in contemporary European societies. A consequence of welcome shifts in life expectancy and fertility, it nevertheless entails important challenges for the adequacy, sustainability, and competitiveness of social and economic systems. [less ▲]

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See detailCrosstalk between different family members: IL27 recapitulates IFNγ responses in HCC cells, but is inhibited by IL6-type cytokines
Rolvering, Catherine UL; Zimmer, Andreas; Kozar, Ines UL et al

in BBA Molecular Cell Research (2017)

Interleukin-27 (IL27) is a type-I-cytokine of the IL6/IL12 family predominantly secreted by activated macrophages and dendritic cells. In the liver, IL27 expression was observed to be upregulated in ... [more ▼]

Interleukin-27 (IL27) is a type-I-cytokine of the IL6/IL12 family predominantly secreted by activated macrophages and dendritic cells. In the liver, IL27 expression was observed to be upregulated in patients with hepatitis B, and sera of hepatocellular carcinoma (HCC) patients contain significantly elevated levels of IL27 compared to healthy controls or patients with hepatitis and/or liver cirrhosis. In this study, we show that IL27 induces STAT1 and STAT3 phosphorylation in 5 HCC lines and 3 different types of non-transformed liver cells. We were especially interested in the relevance of the IL27-induced STAT3 activation in liver cells. Thus, we compared the IL27 responses with those induced by IFNγ (STAT1-dominated response) or IL6-type cytokines (IL6, hyper-IL6 (hy-IL6) or OSM) (STAT3-dominated response) by microarray analysis and find that in HCC cells, IL27 induces an IFNγ-like, STAT1-dependent transcriptional response, but we do not find an effective STAT3-dependent response. Validation experiments corroborate the finding from the microarray evaluation. Interestingly, the availability of STAT1 seems critical in the shaping of the IL27 response, as the siRNA knock-down of STAT1 revealed the ability of IL27 to induce the acute-phase protein γ-fibrinogen, a typical IL6 family characteristic. Moreover, we describe a crosstalk between the signaling of IL6-type cytokines and IL27: responses to the gp130-engaging cytokine IL27 (but not those to IFNs) can be inhibited by IL6-type cytokine pre-stimulation, likely by a SOCS3-mediated mechanism. Thus, IL27 recapitulates IFNγ responses in liver cells, but differs from IFNγ by its sensitivity to SOCS3 inhibition. [less ▲]

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See detailZeitgenössisches Theater und die Initiative "Kulturhauptstadt Europa"
Bloch, Natalie UL

Presentation (2017, February 15)

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See detailTo Score and to Protect? Big Data (and Privacy) Meet SME Credit Risk in the UK
Robinson, Gavin UL; Marriott, Jane

in International Data Privacy Law (2017), 7(1), 48-69

Recent UK legislation facilitating the credit scoring of small and medium-sized enterprises using Big Data techniques and Open Data sources threatens to further hollow out information management norms and ... [more ▼]

Recent UK legislation facilitating the credit scoring of small and medium-sized enterprises using Big Data techniques and Open Data sources threatens to further hollow out information management norms and data subject rights enshrined in privacy and data protection law just as it is gathering unprecedented momentum in courts and on statute books across the EU. After examining the economic rationale for such measures and their envisaged impact on the credit risk industry, we argue that the associated regulatory re-shuffling and privacy-related safeguards are highly unlikely to address adequately the serious accuracy, transparency, and accountability concerns of individual data subjects. Would the effective, full enforcement of data protection principles and data subject rights really cripple the credit reference industry to the detriment of the nascent economic recovery, or is there a middle path and will the forthcoming EU General Data Protection Regulation provide it? [less ▲]

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See detail15 Jahre PISA: Eine Bilanz für Luxemburg
Ugen, Sonja UL; Fischbach, Antoine UL

Article for general public (2017)

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See detailInsights into ligand stimulation effects on gastro-intestinal stromal tumors signalling.
Bahlawane, Christelle; Schmitz, Martine UL; Letellier, Elisabeth UL et al

in Cell Signal (2017)

Mutations in KIT or PDGFRA are responsible for >85% of gastrointestinal stromal tumors. The introduction of imatinib in the GIST therapy scheme revolutionized the patient outcome. Unfortunately, the ... [more ▼]

Mutations in KIT or PDGFRA are responsible for >85% of gastrointestinal stromal tumors. The introduction of imatinib in the GIST therapy scheme revolutionized the patient outcome. Unfortunately, the therapy allows the disease stabilization instead of curation. Furthermore the resistance to the inhibitor arises in most cases within two first years of therapy. A thorough investigation of the signalling pathways activated by the major PDGFRA and KIT mutants encountered in the GIST landscape allowed to identify striking differences between the two receptor tyrosine kinases. PDGFRA mutants were not responsive to their ligand, PDGFAA, and displayed a high constitutive kinase activity. In contrast, all KIT mutants retained, in addition to their constitutive activation, the ability to be stimulated by their ligand. Kit mutants displayed a lower intrinsic kinase activity relative to PDGFRA mutants, while the KIT Exon 11 deletion mutant exhibited the highest intrinsic kinase activity among KIT mutants. At the transcriptomic level, the MAPK pathway was established as the most prominent activated pathway, which is commonly up-regulated by all PDGFRA and KIT mutants. Inhibition of this pathway, using the MEK inhibitor PD0325901, reduced the proliferation of GIST primary cells at nanomolar concentrations. Altogether, our data demonstrate the high value of MEK inhibitors for combination therapy in GIST treatment and more importantly the interest of evaluating the SCF expression profile in GIST patients presenting KIT mutations. [less ▲]

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See detailPopulism [glossary]
Chiocchetti, Paolo UL

E-print/Working paper (2017)

A chameleonic concept, populism can be defined as an ideology, a communication style, a political strategy, or a misguided category. Its key elements are a positive appreciation of people, a negative view ... [more ▼]

A chameleonic concept, populism can be defined as an ideology, a communication style, a political strategy, or a misguided category. Its key elements are a positive appreciation of people, a negative view of the elite, and the exaltation of untrammeled popular sovereignty against representative democracy and liberal constitutionalism. The fortune of the term, despite its theoretical and practical drawbacks, is the reflection of intrinsic antinomies of modern democracy and of a growing popular dissatisfaction toward the performance of representative governments and institutions. [less ▲]

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See detailDoes #like4like indeed provoke more likes?
zhang, Yang; Ni, Minyue; Han, Weili et al

in Proceedings of the 16th IEEE/WIC/ACM International Conference on Web Intelligence (WI'17) (2017)

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See detailImpulsivity influences betting under stress in laboratory gambling
Canale, Natale; Rubaltelli, Enrico; Vieno, Alessio et al

in Scientific Reports (2017), 7

Although recent research suggests that acute stress influences subsequent decision-making under ambiguity, less is known about the role of personality variables in this relationship. This study tested ... [more ▼]

Although recent research suggests that acute stress influences subsequent decision-making under ambiguity, less is known about the role of personality variables in this relationship. This study tested whether impulsivity traits and acute stress differentially influence the way in which a prior feedback is incorporated into further decisions involving ambiguity. Sixty college students (50% male; aged 18–25 years) were randomly assigned to a stress versus a non-stress condition before completing a laboratory gambling task. The results revealed that independently of the stress condition, subjects behaved as if the odds of winning increase after a single loss. Additionally, stress effects varied as a function of impulsivity traits. Individuals who lacked perseverance (i.e., had difficulty focusing on a difficult or boring task) gambled more after experiencing a loss in the stress condition than did those in the control condition. The present study supports that impulsivity traits can explain the differential effect of stress on the relationship between prior feedback and choices made under ambiguity [less ▲]

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See detailIdentifying Irregular Power Usage by Turning Predictions into Holographic Spatial Visualizations
Glauner, Patrick UL; Dahringer, Niklas; Puhachov, Oleksandr et al

in Proceedings of the 17th IEEE International Conference on Data Mining Workshops (ICDMW 2017) (2017)

Power grids are critical infrastructure assets that face non-technical losses (NTL) such as electricity theft or faulty meters. NTL may range up to 40% of the total electricity distributed in emerging ... [more ▼]

Power grids are critical infrastructure assets that face non-technical losses (NTL) such as electricity theft or faulty meters. NTL may range up to 40% of the total electricity distributed in emerging countries. Industrial NTL detection systems are still largely based on expert knowledge when deciding whether to carry out costly on-site inspections of customers. Electricity providers are reluctant to move to large-scale deployments of automated systems that learn NTL profiles from data due to the latter's propensity to suggest a large number of unnecessary inspections. In this paper, we propose a novel system that combines automated statistical decision making with expert knowledge. First, we propose a machine learning framework that classifies customers into NTL or non-NTL using a variety of features derived from the customers' consumption data. The methodology used is specifically tailored to the level of noise in the data. Second, in order to allow human experts to feed their knowledge in the decision loop, we propose a method for visualizing prediction results at various granularity levels in a spatial hologram. Our approach allows domain experts to put the classification results into the context of the data and to incorporate their knowledge for making the final decisions of which customers to inspect. This work has resulted in appreciable results on a real-world data set of 3.6M customers. Our system is being deployed in a commercial NTL detection software. [less ▲]

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See detailOn the Incidence of Taxation in Matching Markets.
Dupuy, Arnaud UL

Presentation (2017)

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See detail(Education for) Sustainable Development in Geography Education
Sprenger, Sandra; Nienaber, Birte UL

in Journal of Geography in Higher Education (2017)

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See detailCHILDCARE, QUALITY AND LOCATION: AN HEDONIC APPROACH
Dupuy, Arnaud UL

Presentation (2017)

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See detailVoluntary disclosure, ownership structure, and corporate debt maturity: A study of French listed firms
Derouiche, Imen UL

Scientific Conference (2017)

This study examines the effect of voluntary disclosure on the corporate debt maturity structure when control is concentrated and explores the role of controlling shareholder’s excess control rights in ... [more ▼]

This study examines the effect of voluntary disclosure on the corporate debt maturity structure when control is concentrated and explores the role of controlling shareholder’s excess control rights in this effect. Using a sample of 440 French listed firms over the period 2007-2013, the empirical results indicate that firms with higher voluntary disclosure have more long-term debt, suggesting that voluntary disclosure is valuable for lenders, thus allowing firms to access to more long-maturity debt. We also find that this positive effect is significant only in firms where controlling owners have high levels of excess control rights, meaning that the presence of entrenched controlling shareholders makes voluntary disclosure more highly valued by lenders. Our results provide interesting evidence of the substitution-monitoring effects between short-term debt and voluntary disclosure in firms with concentrated control. Our research also lends support to the findings of recent work that better disclosure policies are viewed more positively by the market in environments where the risk of wealth expropriation by controlling shareholders is higher. [less ▲]

Detailed reference viewed: 20 (1 UL)