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See detailInterview with...Ingrid de Saint-Georges
de Saint-Georges, Ingrid UL; Baranova, Valeriya

Article for general public (2015)

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See detailInterview: Dr. Jakob Pietschnig und der Flynn-Effekt.
Baudson, Tanja Gabriele UL

Article for general public (2016)

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See detailInterweave/Underlay Cognitive Radio Techniques and Applications in Satellite Communication Systems
Sharma, Shree Krishna UL

Doctoral thesis (2014)

The demand for precious radio spectrum is continuously increasing while the available radio frequency resource has become scarce due to spectrum segmentation and the dedicated frequency allocation of ... [more ▼]

The demand for precious radio spectrum is continuously increasing while the available radio frequency resource has become scarce due to spectrum segmentation and the dedicated frequency allocation of standardized wireless systems. This scarcity has led to the concept of cognitive radio communication which comprises a variety of techniques capable of allowing the coexistence of licensed and unlicensed systems over the same spectrum. In this context, this thesis focuses on interweave and underlay cognitive radio paradigms which are widely considered as important enablers for realizing cognitive radio technology. In the interweave paradigm, an unlicensed user explores the spectral holes by means of some spectrum awareness methods and utilizes the available spectral availabilities opportunistically while in the underlay paradigm, an unlicensed user is allowed to coexist with the licensed user only if sufficient protection to the licensed user can be guaranteed. Starting with a detailed overview of the existing techniques, this thesis provides contributions in both theoretical and the practical aspects of these paradigms. This thesis is structured into two main parts as described below. One of the important capabilities required for a cognitive radio transceiver is to be able to acquire the knowledge of its surrounding radio environment in order to utilize the available spectral opportunities efficiently. The higher the level of information it can acquire, the better becomes the spectrum utilization. In this context, the first part of this thesis focuses on spectrum awareness techniques such as spectrum sensing, signal to noise ratio estimation and sparsity order estimation which are useful for realizing interweave and underlay based cognitive transceivers as well as a hybrid cognitive transceiver, which overcomes the drawbacks of both the above approaches. The effects of noise and channel correlations, which are often neglected in the existing literature, are considered in our analysis. In the above context, firstly, we propose new sensing thresholds for the eigenvalue based sensing approach using recent results from random matrix theory in order to achieve the improved sensing in correlated scenarios. Then we study the signal to noise ratio estimation problem for both narrowband and wideband transceivers with the help of a detailed theoretical analysis under the signal plus noise hypothesis for a range of correlated scenarios. Subsequently, we study the problem of compressive sparsity order estimation in order to estimate the sparsity order of the carrier occupancy over the wide spectrum using a compressive sensing approach. In addition, we carry out the performance analysis of a hybrid cognitive transceiver which combines the spectrum sensing approach with a power control-based underlay approach. The second part of this thesis introduces the concept of cognitive satellite communications which is a rather unexplored area in the literature despite its significant benefits to both satellite and terrestrial operators. This concept has been motivated due to the limited availability of the satellite spectrum as well as the continuously increasing demand of broadband multimedia, broadcast and interactive satellite services. Subsequently, we study the applications of various cognitive radio techniques in satellite communication systems focusing on the following two scenarios: (i) Hybrid cognitive satellite communication which deals with the spectral coexistence of satellite systems with the terrestrial systems, and (ii) Dual cognitive satellite communication which deals with the spectral coexistence of two satellite systems operating over the same coverage area. Understanding the characteristics of coexisting systems is of great importance while applying a suitable cognitive radio technique. In this context, this thesis exploits the specific characteristics of satellite systems in order to map a suitable cognitive radio technique to a specific scenario. For hybrid cognitive scenarios, we propose the following enabling techniques: (a) Interference modeling, (b) Harmful interference detection, (c) Cognitive beamforming including both transmit and receive beamforming, and (d) Dual-polarized spectrum sensing. Similarly, for dual cognitive scenarios, we propose the following techniques: (i) Cognitive interference alignment, (ii) Cognitive beamhopping, and (iii) Dual-polarized spectrum sensing. Finally, we provide interesting open research issues in the considered domain. [less ▲]

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See detailInterword and intraword pause threshold in writing
Chenu, Florence; Pellegrino, François; Jisa, Harriet et al

in Frontiers in Psychology (2014), 5

Writing words in real life involves setting objectives, imagining a recipient, translating ideas into linguistic forms, managing grapho-motor gestures, etc. Understanding writing requires observation of ... [more ▼]

Writing words in real life involves setting objectives, imagining a recipient, translating ideas into linguistic forms, managing grapho-motor gestures, etc. Understanding writing requires observation of the processes as they occur in real time. Analysis of pauses is one of the preferred methods for accessing the dynamics of writing and is based on the idea that pauses are behavioral correlates of cognitive processes. However, there is a need to clarify what we are observing when studying pause phenomena, as we will argue in the first section. This taken into account, the study of pause phenomena can be considered following two approaches. A first approach, driven by temporality, would define a threshold and observe where pauses, e.g., scriptural inactivity occurs. A second approach, linguistically driven, would define structural units and look for scriptural inactivity at the boundaries of these units or within these units. Taking a temporally driven approach, we present two methods which aim at the automatic identification of scriptural inactivity which is most likely not attributable to grapho-motor management in texts written by children and adolescents using digitizing tablets in association with Eye and Pen© (Chesnet and Alamargot, 2005). The first method is purely statistical and is based on the idea that the distribution of pauses exhibits different Gaussian components each of them corresponding to a different type of pause. After having reviewed the limits of this statistical method, we present a second method based on writing dynamics which attempts to identify breaking points in the writing dynamics rather than relying only on pause duration. This second method needs to be refined to overcome the fact that calculation is impossible when there is insufficient data which is often the case when working with young scriptors. [less ▲]

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See detailIntestinal-Cell Kinase and Juvenile Myoclonic Epilepsy.
Lerche, Holger; Berkovic, Sam F.; Lowenstein, Daniel H. et al

in New England Journal of Medicine (2019), 380(16), 24

With regard to the article by Bailey et al. (March 15, 2018, issue) on the potential role of variants in the gene encoding intestinal cell kinase (ICK) in genetic generalized epilepsies, including ... [more ▼]

With regard to the article by Bailey et al. (March 15, 2018, issue) on the potential role of variants in the gene encoding intestinal cell kinase (ICK) in genetic generalized epilepsies, including juvenile myoclonic epilepsy: We attempted replication by rechecking for enrichment of ICK variants in two previously published analyses of mainly familial cases of genetic generalized epilepsy, which included a total of 1149 cases of genetic generalized epilepsy and 5911 ethnically matched controls. We analyzed the burden of single-gene rare variants with the use of whole exome sequencing data, applying population stratification and both sample and variant quality control. We found no evidence of an enrichment of ICK variants in genetic generalized epilepsies or juvenile myoclonic epilepsy. Specifically, we did not detect a nonsynonymous variant in 357 persons with juvenile myoclonic epilepsy at a minor allele frequency at or below 0.1%. Although we cannot exclude the possibility that ICK variants may be population-specific risk factors for juvenile myoclonic epilepsy, the lack of validation in our cohorts does not support a true disease association but rather suggests that the authors’ results may be due to chance, possibly owing to methodologic issues (see the Supplementary Appendix, available with the full text of this letter at NEJM.org). [less ▲]

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See detailInto the ground
Hesse, Markus UL

in Arch + (2018), (231), 78-83

How the financialization of property markets and land use puts cities under pressure.

Detailed reference viewed: 125 (20 UL)
See detailInto the wild? Freie Dramaturgie und freie Szene
Tropper, Elisabeth UL

Conference given outside the academic context (2011)

Detailed reference viewed: 38 (2 UL)
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See detailInto the Μaze of Legitimacy and Efficiency; the Single Resolution Board as a Necessity
Asimakopoulos, Ioannis UL; Lamaris-Adamis, Christos

in Dogaru, Tatiana-Camelia (Ed.) (Re)forming Public Administration Paradigms in Global Governance Context (2018)

Detailed reference viewed: 89 (8 UL)
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See detailDie Intonation final fallender Nuklei. Eine kontrastive Untersuchung zum Hamburgischen und Berlinischen
Gilles, Peter UL

in Germanistische Linguistik (2001), 157-158

Detailed reference viewed: 60 (0 UL)
See detailIntonation regionaler Varietäten des Deutschen. Vorstellung eines Forschungsprojekts
Auer, Peter; Gilles, Peter UL; Peters, Jörg et al

in Stellmacher, Dieter (Ed.) Dialektologie zwischen Tradition und Neuansätzen. Beiträge der Internationalen Dialektologentagung. Göttingen, 19.-21. Oktober 1998 (2000)

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See detailIntorno al-i concetto-i di datore di lavoro. A proposito di The Concept of The Employer di Jeremias Prassl
Ratti, Luca UL

in Giornale di Diritto del Lavoro e delle Relazioni Industriali (2016)

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See detailIntra-household allocation with shared expenditure choices: experimental evidence from Filipino migrants
Joxhe, Majlinda UL; De Arcangelis, Giuseppe

in Review of Economics of the Household (2020)

This paper shows that sharing information concerning expenditure choices between a migrant and the recipient affects the migrant’s allocation patterns. In a lab-in-the-field experiment, Filipino migrants ... [more ▼]

This paper shows that sharing information concerning expenditure choices between a migrant and the recipient affects the migrant’s allocation patterns. In a lab-in-the-field experiment, Filipino migrants are asked to earmark an in-kind budget to be delivered to their most closely connected household (MCCH). When the MCCH is fully aware of the migrant’s decisions (i.e., symmetric information), we observe that the migrant raises the portion for consumption goods in the range of 10.0-10.5% with respect to the case when the migrant’s choices are not disclosed (i.e., asymmetric information). Moreover, when sharing information, the migrant relies on more involvement of the recipient household and lowers by 7-9% the allocation to expenses she could monitor ex-post more strictly. The former result is consistent with the signaling motive, whereas the latter supports the presence of strategic behavior by the migrant remitter. These findings are more significant for intra- rather than inter-household transfers and provide insights for conditional cash transfer policies. [less ▲]

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See detailIntra-query Adaptivity for MapReduce Query Processing Systems
Lucas Filho, Edson Ramiro UL; Cunha De Almeida, Eduardo UL; Le Traon, Yves UL

in IDEAS 2014 : 18th International Database Engineering Applications Symposium (2014)

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See detailIntracellular metabolite profiling of platelets: evaluation of extraction processes and chromatographic strategies.
Paglia, Giuseppe; Magnusdottir, Manuela; Thorlacius, Steinunn et al

in Journal of Chromatography. B : Analytical Technologies in the Biomedical & Life Sciences (2012), 898

An extraction method for intracellular metabolite profiling should ideally be able to recover the broadest possible range of metabolites present in a sample. However, the development of such methods is ... [more ▼]

An extraction method for intracellular metabolite profiling should ideally be able to recover the broadest possible range of metabolites present in a sample. However, the development of such methods is hampered by the diversity of the physico-chemical properties of metabolites as well as by the specific characteristics of samples and cells. In this study, we report the optimization of an UPLC-MS method for the metabolite analysis of platelet samples. The optimal analytical protocol was determined by testing seven different extraction methods as well as by employing two different LC-MS methods, in which the metabolites were separated by using hydrophilic interaction liquid chromatography (HILIC) and reversed phase liquid chromatography (RPLC). The optimal conditions were selected using the coverage of the platelets' metabolome, the response of the identified metabolites, the reproducibility of the analytical method, and the time of the analysis as main evaluation criteria. Our results show that methanol-water (7:3) extraction coupled with HILIC-MS method provides the best compromise, allowing identification of 107 metabolites in a platelet cell extract sample, 91% of them with a RSD% lower than 20. A higher number of metabolites could be detected when analyzing the platelet samples with two different LC-MS methods or when using complementary extraction methods in parallel. [less ▲]

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See detailIntracellular recording of human cardiac action potentials on market-available multielectrode array platforms
Melle, Giovanni; Bruno, Giulia; Maccaferri, Nicolò UL et al

in Frontiers in Bioengineering and Biotechnology (2020), 8

High quality attenuated intracellular action potentials from large cell networks can be recorded on multi-electrode arrays by means of 3D vertical nanopillars using electrical pulses. However,most of the ... [more ▼]

High quality attenuated intracellular action potentials from large cell networks can be recorded on multi-electrode arrays by means of 3D vertical nanopillars using electrical pulses. However,most of the techniques require complex 3D nanostructures that prevent the straightforward translation into marketable products and the wide adoption in the scientific community. Moreover, 3D nanostructures are often delicate objects that cannot sustain several harsh use/cleaning cycles. On the contrary, laser optoacoustic poration allows the recording of action potentials on planar nanoporous electrodes made of noble metals. However, these constraints of the electrode material and morphology may also hinder the full exploitation of this methodology. Here, we show that optoacoustic poration is also very effective for porating cells on a large family of MEA electrode configurations, including robust electrodes made of nanoporous titanium nitride or disordered fractal-like gold nanostructures. This enables the recording of high quality cardiac action potentials in combination with optoacoustic poration, providing thus attenuated intracellular recordings on various already commercial devices used by a significant part of the research and industrial communities. [less ▲]

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See detailIntractable conflicts in Africa: The international response to the Darfur and South Sudan crises
Owiso, Owiso UL; Boshoff, Elsabé; Mamhare, Tapiwa et al

in Global Campus Human Rights Journal (2017), 1(2), 287-314

This article considers the intractable conflicts and human rightssituations in Darfur, Sudan and South Sudan, respectively, against theinternational responses they elicited. Intractable conflicts are ... [more ▼]

This article considers the intractable conflicts and human rightssituations in Darfur, Sudan and South Sudan, respectively, against theinternational responses they elicited. Intractable conflicts are conflicts that havelasted for a long time with resistance to settlement despite various attempts atintervention and conciliation. These conflicts from neighbouring nations haveboth elicited extensive engagement from the international and regionalcommunities but, while some clarity regarding the direction to be taken has beenachieved in the case of South Sudan, the situation in Darfur remains dire. Thearticle analyses the difference in the peace-building approaches in the twoconflicts and how these approaches have contributed to the different outcomes inDarfur and South Sudan. Following an exposition of intractability in theintroduction, the second section applies the factors identified to the case ofDarfur, confirming that this indeed is an intractable situation. It then considersthe international response to the conflict in Darfur and the mechanismsemployed by the global and the regional community in an attempt to addressthis conflict. The third section considers the situation in South Sudan and theinternational response, noting that efforts were led by the regional and sub-regional bodies, with the UN’s role being to complement these efforts. Themethodology employed is a comparative analysis, in which the internationaland regional legal and institutional responses to the crisis in South Sudan areanalysed with a view to identifying the lessons to be applied in addressing thesituation in Darfur, utilising theoretical and functional approaches to legal andpolitical interventions. The final section draws from the insights gained incomparing the international response in Darfur and South Sudan, and concludesby attempting to extract general principles about intractability and theeffectiveness of international responses to situations considered to be intractable,noting in particular the importance of regional and sub-regional bodies takingthe lead in efforts to resolve intractable conflicts. [less ▲]

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See detailIntragrain charge transport in kesterite thin films-Limits arising from carrier localization
Hempel, Hannes; Redinger, Alex UL; Repins, Ingrid et al

in JOURNAL OF APPLIED PHYSICS (2016), 120(17),

Intragrain charge carrier mobilities measured by time-resolved terahertz spectroscopy in state of the art Cu2ZnSn(S,Se)(4) kesterite thin films are found to increase from 32 to 140 cm(2) V-1 s(-1) with ... [more ▼]

Intragrain charge carrier mobilities measured by time-resolved terahertz spectroscopy in state of the art Cu2ZnSn(S,Se)(4) kesterite thin films are found to increase from 32 to 140 cm(2) V-1 s(-1) with increasing Se content. The mobilities are limited by carrier localization on the nanometer-scale, which takes place within the first 2 ps after carrier excitation. The localization strength obtained from the Drude-Smith model is found to be independent of the excited photocarrier density. This is in accordance with bandgap fluctuations as a cause of the localized transport. Charge carrier localization is a general issue in the probed kesterite thin films, which were deposited by co-evaporation colloidal inks, and sputtering followed by annealing with varying Se/S contents and yield 4.9\%-10.0 efficiency in the completed device. (C) 2016 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). [less ▲]

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See detailIntransitivity cycles and their transformations: How dynamically adapting systems function
Valsiner, Jaan UL; Poddiakov, A. N.

in Rudolph, Lee (Ed.) Qualitative mathematics for the social sciences (2013)

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See detailIntrapreneurship and Innovative Work Behavior
Segers, Mien; Geraudel, Mickaël UL

Conference given outside the academic context (2015)

Detailed reference viewed: 102 (2 UL)