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See detailF center in lithium fluoride revisited: Comparison of solid-state physics and quantum-chemistry approaches
Karsai, Ferenc; Tiwald, Paul; Laskowski, Robert et al

in Physical Review. B : Condensed Matter (2014), 89

We revisit the theoretical description of the F color center in lithium fluoride employing advanced complementary ab initio techniques.We compare the results from periodic supercell calculations involving ... [more ▼]

We revisit the theoretical description of the F color center in lithium fluoride employing advanced complementary ab initio techniques.We compare the results from periodic supercell calculations involving density-functional theory (DFT) and post-DFT techniques with those from the embedded-cluster approach involving quantumchemical many-electron wave-function techniques. These alternative approaches yield results in good agreement with each other and with the experimental data provided that correlation effects are properly taken into account. [less ▲]

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See detailF wie Frühling
Heimböckel, Dieter UL

Article for general public (2012)

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See detailF-Alloy: An Alloy Based Model Transformation Language
Gammaitoni, Loïc UL; Kelsen, Pierre UL

in Theory and Practice of Model Transformations (2015)

Model transformations are one of the core artifacts of a model-driven engineering approach. The relational logic language Alloy has been used in the past to verify properties of model transformations. In ... [more ▼]

Model transformations are one of the core artifacts of a model-driven engineering approach. The relational logic language Alloy has been used in the past to verify properties of model transformations. In this paper we introduce the concept of functional Alloy modules. In essence a functional Alloy module can be viewed as an Alloy module representing a model transformation. We describe a sublanguage of Alloy called F-Alloy that allows the specification of functional Alloy modules. Modules in F-Alloy are analysable using the powerful automatic analysis features of Alloy but can also be interpreted efficiently without the use of backtracking. [less ▲]

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See detailFabricating National Unity in Torn Contexts: World War I and the Education of Future Citizens in Multilingual Nation-States
Tröhler, Daniel UL

in McCulloch, Gary (Ed.) Abstracts. Education, War and Peace (2014, July)

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See detailFabricating National Unity in Torn Contexts: World War I in the Multilingual Countries of Switzerland and Luxembourg
Gardin, Matias UL; Brühwiler, Ingrid

in Gearóid, Barry; Dal Lago, Enrico; Healy, Róisín (Eds.) Small Nations and Colonial Peripheries in World War I (2016)

Switzerland and Luxembourg are both multilingual countries whose national raison d’être does not refer to one language or culture. During the First World War, both countries experienced inner political ... [more ▼]

Switzerland and Luxembourg are both multilingual countries whose national raison d’être does not refer to one language or culture. During the First World War, both countries experienced inner political conflicts; consequently, the effects of the war on the education of national citizens are of crucial interest. In this article, we analyse teacher journals to highlight the ideas and principles of the 1910s and relate them to the topics of civics, war and peace. In this way, we examine how these two countries interpreted neutrality, shared a commitment to and addressed multilingualism, and sought to educate national citizens. In Switzerland, two major teacher journals immediately reacted to the new circumstance of war with articles and lessons for schools about war and peace, whereas in Luxembourg similar articles appeared only after 1916. Both countries experienced similar discussions about WWI and national unity, peace, and daily difficulties in economic, social and political life. Additionally, some aspects of neutrality were addressed similarly but fostered different aims regarding the military or solidarity. Thus, although the First World War challenged schools – and therefore teachers – and led to different arguments in the two countries on the way that national citizens were to be educated, the proclamations of patriotism, virtues and morals were similar. [less ▲]

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See detailFabricating the teacher’s soul in teacher education
Popkewitz, Thomas S. UL; Kirchgasler, C.

in Fejes, A.; Nichols, C. (Eds.) Foucault and a politics of confession in education (2014)

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See detailFabrication and characterization of kesterite Cu2ZnSnS4 thin films deposited by electrostatic spray assisted vapour deposition method
Liu, J. P.; Choy, Kwang-Leong; Placidi, M. et al

in Physica Status Solidi A. Applications and Materials Science (2014)

Most of the high efficiency kesterite solar cells are fabricated by vacuum or hydrazine-based solution methods which have drawbacks, such as high cost, high toxicity or explosivity. In our contribution ... [more ▼]

Most of the high efficiency kesterite solar cells are fabricated by vacuum or hydrazine-based solution methods which have drawbacks, such as high cost, high toxicity or explosivity. In our contribution, an alternative non-vacuum and environmental friendly deposition technology called electrostatic spray assisted vapour deposition (ESAVD) has been used for the cost-effective growth of Cu2ZnSnS4 (CZTS) thin films with well controlled structure and composition. CZTS films have been characterized using a combination of XRD, XPS, SEM-EDX, AFM, and Raman spectroscopy. The results demonstrated that adherent, uniform and homogeneous CZTS films without apparent secondary phases have been produced by ESAVD. The atomic ratios measured by EDX are Cu/(Zn + Sn) = 0.88 and Zn/Sn = 1.17,which are very close with the reported high efficiency solar cells and can be finely tuned by formulating the precursor.CZTS films exhibited a typical optical band gap of 1.53 eV from UV–Vis analysis. Cu2ZnSnS4 produced by the ESAVD are being optimized towards the fabrication of high efficiency photovoltaic devices. [less ▲]

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See detailFabrication and performance of AlGaN/GaN HEMTs on (111) Si substrates
Javorka, P.; Alam, A.; Marso, Michel UL et al

in Physica Status Solidi A. Applications and Materials Science (2002), 194(2), 472-475

In the current work the performance of AlGaN/GaN HEMTs fabricated on silicon substrates is presented. The AlGaN/GaN material structures were grown on (111) Si by MOVPE. Static I–V characteristics with a ... [more ▼]

In the current work the performance of AlGaN/GaN HEMTs fabricated on silicon substrates is presented. The AlGaN/GaN material structures were grown on (111) Si by MOVPE. Static I–V characteristics with a saturation current of 0.91 A/mm and a peak extrinsic transconductance of 122 mS/mm were measured and show minimal thermal effects. For devices with a gate length of 0.7 um and 0.5 um, a unity gain frequency of 20 GHz and 32 GHz and a maximum frequency of oscillation of 22 GHz and 27 GHz, respectively were obtained. The unity gain frequencies are the highest values reported so far on AlGaN/GaN/Si HEMTs and fully comparable to those known for devices using sapphire and SiC substrates. However, the fmax to fT ratio is only about 1, which indicates on parasitic conduction through the Si substrate under small signal conditions. It is shown that the saturation current and the transconductance decrease much less with increased temperature than known for similar devices grown on sapphire. [less ▲]

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See detailFabrication and performance of hybrid photoconductive devices based on freestanding LT-GaAs, Ultrafast Phenomena in Semiconductors and Nanostructure Materials VIII,
Adam, R.; Mikulics, M.; Wu, S. et al

in Proceedings of SPIE (2004), 5353 (2004)

We report on fabrication and high-frequency performance of our photodetectors and photomixers based on freestanding low-temperature-grown GaAs (LT-GaAs). In our experiments, the LT-GaAs/AlAs bilayers were ... [more ▼]

We report on fabrication and high-frequency performance of our photodetectors and photomixers based on freestanding low-temperature-grown GaAs (LT-GaAs). In our experiments, the LT-GaAs/AlAs bilayers were grown on 2-inch diameter, semi-insulating GaAs wafers by a molecular beam epitaxy. Next, the bilayer was patterned to form 10 × 10 μm2 to 150 × 150 μm2 structures using photolithography and ion beam etching. The AlAs layer was then selectively etched in diluted HF solution, and the LT-GaAs device was lifted from its substrate and transferred on top of a variety of substrates including Si, MgO/YBaCuO, Al2O3, and a plastic foil. Following the transfer, metallic coplanar transmission lines were fabricated on top of the LT-GaAs structure, forming a metal semiconductor-metal photodetectors or photomixer structures. Our freestanding devices exhibited above 200 V breakdown voltages and dark currents at 100 V below 3×10-7 A. Device photoresponse was measured using an electro-optic sampling technique with 100-fs-wide laser pulses at wavelengths of 810 nm and 405 nm as the excitation source. For 810-nm excitation, we measured 0.55 ps-wide electrical transients with voltage amplitudes of up to 1.3 V. The signal amplitude was a linear function of the applied voltage bias, as well as a linear function of the laser excitation power, below well-defined saturation thresholds. Output power from the freestanding photomixers was measured with two beam laser illumination experimental setup. Reported fabrication technique is suitable for the LT-GaAs integration with a range of semiconducting, superconducting, and organic materials for high-frequency hybrid optoelectronic applications. [less ▲]

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See detailFabrication of Laterally Displaced Porous Silicon Filters
Marso, Michel UL; Wolter, M.; Arens-Fischer, R. et al

in Thin Solid Films (2001), 382(2001), 218-221

Porous silicon superlattices have been used to manufacture laterally displaced dielectric filters with different optical properties on one substrate. Two different fabrication processes for two-colour ... [more ▼]

Porous silicon superlattices have been used to manufacture laterally displaced dielectric filters with different optical properties on one substrate. Two different fabrication processes for two-colour microfilter arrays are presented. Both methods overcome the problem of non-uniform optical properties of the well-known procedure where two filter stacks are grown one upon another, with subsequent partial removal of the upper filter by reactive ion etching. The novel methods give uniform optical properties of the two filter areas, profiting from the main property of the formation process of porous silicon: the formation of porous silicon occurs only at the porous silicon substrate interface. [less ▲]

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See detailFabrication of Si tunnel diodes for c-Si based tandem solar cells using proximity rapid thermal diffusion
Fave, Alain; Lelièvre, Jean-François; Gallet, Thibaut Quentin UL et al

in Energy Procedia (2017), 124

Increasing competitiveness of photovoltaic (PV) devices is currently an important objective in technological research, especially with the development of tandem solar cells based on c-Si as the bottom ... [more ▼]

Increasing competitiveness of photovoltaic (PV) devices is currently an important objective in technological research, especially with the development of tandem solar cells based on c-Si as the bottom cell. For a monolithical structure, a tunnel diode in between the top and bottom cells is necessary. In this work we report on the development of the fabrication of Si tunnel junction using a combination of spin-on doping and proximity rapid thermal diffusion. A desirable attribute of this process is simplicity. Two different structures p++/n++ or n++/p++ were fabricated on (100) Si substrates. Carrier density profiles were measured by ECV to characterize the shallow doping profiles. Vertical tunnel diodes were fabricated and I(V) characteristics are presented. It is shown that device peak current densities up to 270 A/cm² are achieved using this technique, which is the best value reported with such simple technique. [less ▲]

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See detailFabriquer du « bien-être » : tension entre missions chez les personnels d’Etablissements d’Hébergement pour Personnes Âgées Dépendantes (EHPAD) en France
Loffeier, Iris UL

in Nouvelles Pratiques Sociales (2011), 24(Automne), 178

Les institutions d’hébergement pour personnes âgées d’aujourd’hui, en France, rejoignent deux objectifs : celui de faire habiter, et celui de soigner. La rencontre entre ces deux dialectiques offre à ... [more ▼]

Les institutions d’hébergement pour personnes âgées d’aujourd’hui, en France, rejoignent deux objectifs : celui de faire habiter, et celui de soigner. La rencontre entre ces deux dialectiques offre à l’observateur les logiques à l’œuvre dans ces institutions, différentes selon les situations. Trois systèmes co-existants de références y hiérarchisent chacun à sa manière les individus et les objets. Au sein de la « cité marchande », de la « cité industrielle » et de la « cité domestique », les résidents n’occupent pas la même place, et les interactions gagnent à être comprises dans l’entremêlement complexe de ces systèmes de références qui agissent l’institution. [less ▲]

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See detailFace à l'évêque, le comte. Politique ottonienne et pouvoir comtal en Lotharingie à l'époque de Notger
Margue, Michel UL

in Wilkin, Alexis; Kupper, Jean-Louis (Eds.) Evêque et prince. Notger et la Basse-Lotharingie aux alentours de l'an Mil (2013, November)

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See detailFace inversion disrupts the perception of vertical relations between features in the right human occipito-temporal cortex
Goffaux, Valerie; Rossion, Bruno; Sorger, Bettina et al

in Journal of Neuropsychology (2009), 3

The impact of inversion on the extraction of relational and featural face information was investigated in two fMRI experiments. Unlike previous studies, the contribution of horizontal and vertical spatial ... [more ▼]

The impact of inversion on the extraction of relational and featural face information was investigated in two fMRI experiments. Unlike previous studies, the contribution of horizontal and vertical spatial relations were considered separately since they have been shown to be differentially vulnerable to face inversion (Goffaux & Rossion, 2007). Hence, inversion largely affects the perception of vertical relations (e.g. eye or mouth height) while the processing of features (e.g. eye shape and surface) and of horizontal relations (e.g. inter-ocular distance) is affected to a far lesser extent. Participants viewed pairs of faces that differed either at the level of one local feature (i.e. the eyes) or of the spatial relations of this feature with adjacent features. Changes of spatial relations were divided into two conditions, depending on the vertical or horizontal axis of the modifications. These stimulus conditions were presented in separate blocks in the first (block) experiment while they were presented in a random order in the second event-related (ER) experiment. Face-preferring voxels located in the right-lateralized middle fusiform gyrus (rMFG) largely decreased their activity with inversion. Inversion-related decreases were more moderate in left-lateralized middle fusiform gyrus (lMFG). ER experiment revealed that inversion affected rMFG and lMFG activity in distinct stimulus conditions. Whereas inversion affected lMFG processing only in featural condition, inversion selectively affected the processing of vertical relations in rMFG. Correlation analyses further indicated that the inversion effect (IE) observed in rMFG and right inferior occipital gyrus (rIOG) reliably predicted the large behavioural IE observed for the processing of vertical relations. In contrast, lMFG IE correlated with the weak behavioural IE observed for the processing of horizontal relations. Our findings suggest that face configuration is mostly encoded in rMFG, whereas more local aspects of face information, such as features and horizontal spatial relations drive lMFG processing. These findings corroborate the view that the vulnerability of face perception to inversion stems mainly from the disrupted processing of vertical face relations in the right-lateralized network of face-preferring regions (rMFG, rIOG). [less ▲]

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See detailFace perception is tuned to horizontal orientation in the N170 time window
Jacques, Corentin; Schiltz, Christine UL; Goffaux, Valerie

in Journal of Vision (2014), 14(2), 1-18

The specificity of face perception is thought to reside both in its dramatic vulnerability to picture-plane inversion and its strong reliance on horizontally oriented image content. Here we asked when in ... [more ▼]

The specificity of face perception is thought to reside both in its dramatic vulnerability to picture-plane inversion and its strong reliance on horizontally oriented image content. Here we asked when in the visual processing stream face-specific perception is tuned to horizontal information. We measured the behavioral performance and scalp event-related potentials (ERP) when participants viewed upright and inverted images of faces and cars (and natural scenes) that were phase- randomized in a narrow orientation band centered either on vertical or horizontal orientation. For faces, the magnitude of the inversion effect (IE) on behavioral discrimination performance was significantly reduced for horizontally randomized compared to vertically or nonrandomized images, confirming the importance of horizontal information for the recruitment of face- specific processing. Inversion affected the processing of nonrandomized and vertically randomized faces early, in the N170 time window. In contrast, the magnitude of the N170 IE was much smaller for horizontally randomized faces. The present research indicates that the early face- specific neural representations are preferentially tuned to horizontal information and offers new perspectives for a description of the visual information feeding face- specific perception. [less ▲]

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See detailFace Perception: fMRI and Prosopagnosia
Schiltz, Christine UL

Presentation (2011, May 17)

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See detailFace-sensitive responses in the occipital inferior cortex of normal humans through feedback inputs from the fusiform gyrus ?: Evidence from neuroimaging studies of brain-damaged prosopagnosic patients
Schiltz, Christine UL; Caldara, Roberto; Sorger, Bettina et al

Poster (2004, June)

In humans, neuroimaging studies have identified two major visual extrastriate areas presenting face-sensitive responses: in the inferior occipital cortex (‘occipital face area’, OFA), and the middle ... [more ▼]

In humans, neuroimaging studies have identified two major visual extrastriate areas presenting face-sensitive responses: in the inferior occipital cortex (‘occipital face area’, OFA), and the middle fusiform gyrus (the ‘fusiform face area’, FFA), with a right hemispheric dominance. It has been proposed that the OFA, located anteriorly to foveal V4v (Halgren et al., 1999), has a critical role in the early perception of facial features and provides the feedforward outputs to later stages of face processing in both the FFA and the STS (Haxby et al., 2000). However, we have recently reported a normal activation of the right FFA despite a lesion encompassing the region of the right OFA in a brain-damaged prosopagnosic patient, PS (Rossion et al., 2003), suggesting that the face-sensitive responses observed at the level of the OFA in normals may rather arise from feedback connections from the FFA. Here we provide complementary fMRI evidence supporting this view. First, the normal differential activation for faces and objects in the right FFA of PS was observed only for left visual field presentations and is thus unlikely to originate from contralateral intact regions of the occipital cortex (e.g. left OFA). Second, the time-course in the right FFA and left OFA of PS for centrally presented items suggests an earlier differential activity between faces and objects in the most anterior region, the FFA. Finally, we imaged another (prosop)agnosic patient (NS, Delvenne et al., 2004) with a lesion encompassing the right FFA but sparing all posterior visual areas, and failed to disclose any face-sensitive response in his nonetheless structurally and functionnally intact occipital cortex. Together, these findings illustrate the necessary role of both the right FFA and OFA for accurate face perception, and reinforce the hypothesis that a dominant (feedback) connection from the FFA to the OFA subtends face-sensitive responses observed in the latter area when processing faces. [less ▲]

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See detailFace-sensitive responses in the occipital inferior cortex of normal humans through feedback inputs from the fusiform gyrus? Evidence from neuroimaging studies of brain-damaged prosopagnosic patient
Rossion, Bruno; Sorger, Bettina; Schiltz, Christine UL et al

Poster (2004, August 13)

In humans, neuroimaging studies have identified two major visual extrastriate areas presenting face-sensitive responses: in the inferior occipital cortex (‘occipital face area’, OFA), and the middle ... [more ▼]

In humans, neuroimaging studies have identified two major visual extrastriate areas presenting face-sensitive responses: in the inferior occipital cortex (‘occipital face area’, OFA), and the middle fusiform gyrus (the ‘fusiform face area’, FFA), with a right hemispheric dominance. It has been proposed that the OFA, located anteriorly to foveal V4v (Halgren et al., 1999), has a critical role in the early perception of facial features and provides the feedforward outputs to later stages of face processing in both the FFA and the STS (Haxby et al., 2000). However, we have recently reported a normal activation of the right FFA despite a lesion encompassing the region of the right OFA in a brain-damaged prosopagnosic patient, PS (Rossion et al., 2003), suggesting that the face-sensitive responses observed at the level of the OFA in normals may rather arise from feedback connections from the FFA. Here we provide complementary fMRI evidence supporting this view. First, the normal differential activation for faces and objects in the right FFA of PS was observed only for left visual field presentations and is thus unlikely to originate from contralateral intact regions of the occipital cortex (e.g. left OFA). Second, the time-course in the right FFA and left OFA of PS for centrally presented items suggests an earlier differential activity between faces and objects in the most anterior region, the FFA. Finally, we imaged another (prosop)agnosic patient (NS, Delvenne et al., 2004) with a lesion encompassing the right FFA but sparing all posterior visual areas, and failed to disclose any face-sensitive response in his nonetheless structurally and functionnally intact occipital cortex. Together, these findings illustrate the necessary role of both the right FFA and OFA for accurate face perception, and reinforce the hypothesis that a dominant (feedback) connection from the FFA to the OFA subtends face-sensitive responses observed in the latter area when processing faces. [less ▲]

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See detailFacebook’s Real Name Policy: Bye-Bye, Max Mustermann?
Schmitz, Sandra UL

in Journal of Intellectual Property, Information Technology and E-Commerce Law (2013), 4(3), 190-204

Facebook requires all members to use their real names and email addresses when joining the social network. Not only does the policy seem to be difficult to enforce (as the prevalence of accounts with ... [more ▼]

Facebook requires all members to use their real names and email addresses when joining the social network. Not only does the policy seem to be difficult to enforce (as the prevalence of accounts with people’s pets or fake names suggests), but it may also interfere with European (and, in particular, German) data protection laws. A German Data Protection Commissioner recently took action and ordered that Facebook permit pseudonymous accounts as its current anti-pseudonymous policy violates § 13 VI of the German Telemedia Act. This provision requires telemedia providers to allow for an anonymous or pseudonymous use of services insofar as this is reasonable and technically feasible. Irrespective of whether the pseudonymous use of Facebook is reasonable, the case can be narrowed down to one single question: Does German data protection law apply to Facebook? In that respect, this paper analyses the current Facebook dispute, in particular in relation to who controls the processing of personal data of Facebook users in Germany. It also briefly discusses whether a real name policy really presents a fix for anti-normative and anti-social behaviour on the Internet. [less ▲]

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