355 research outputs found
Smart Institutions for Smart Cities
Smart cities employ creativity of the population for innovations supporting social and economic development. In this context, this paper explores the role of framework conditions on special supply effects of university hospitals, which can invite further research institutions for intense collaboration, thereby stimulating innovations. The case study, comparing a hospital in Russia with one in Germany, is based on the concept of the employment multiplier. The results show that exogenously given, but, more importantly, also modifiable framework conditions lead to large differences regarding the employment multiplier. Thus, it should be the concern of smart cities to make smart use of their institutions, such as university hospitals, by adjusting the conditions, under which they are operating. © 2018 Institute of Physics Publishing. All rights reserved
Flexibles Lernen: Erfolgreiche online-gestützte Lernprozesse ermöglichen
Die Digitalisierung im Gesundheitswesen erfordert eine kontinuierliche Weiterqualifikation der betroffenen Berufsgruppen. Die Universität UMIT hat daher 2017 einen online-gestützten, postgraduellen Universitätslehrgang gestartet. Beim didaktischen Design lag ein Schwerpunkt auf der Flexibilität des Lernens, um so den Anforderungen der berufstätigen Teilnehmer/innen besonders zu entsprechen. Dabei wurde neben Flexibilität von Ort und Zeit des Lernens auch Flexibilität z. B. beim Setzen eigener Lernziele und bei Lerninhalten ermöglicht. Wir stellen das gewählte didaktische Design vor und beleuchten auf Basis einer Analyse von Log-Daten, studentischer Evaluationen sowie studentischer Reflexionen die Akzeptanz sowie die Herausforderungen des flexiblen Lernens aus Sicht der Lernenden
Nernst effect of iron pnictide and cuprate superconductors: signatures of spin density wave and stripe order
The Nernst effect has recently proven a sensitive probe for detecting unusual
normal state properties of unconventional superconductors. In particular, it
may sensitively detect Fermi surface reconstructions which are connected to a
charge or spin density wave (SDW) ordered state, and even fluctuating forms of
such a state. Here we summarize recent results for the Nernst effect of the
iron pnictide superconductor , whose ground state evolves
upon doping from an itinerant SDW to a superconducting state, and the cuprate
superconductor which exhibits static stripe
order as a ground state competing with the superconductivity. In , the SDW order leads to a huge Nernst response, which allows
to detect even fluctuating SDW precursors at superconducting doping levels
where long range SDW order is suppressed. This is in contrast to the impact of
stripe order on the normal state Nernst effect in . Here, though signatures of the stripe order are
detectable in the temperature dependence of the Nernst coefficient, its overall
temperature dependence is very similar to that of ,
where stripe order is absent. The anomalies which are induced by the stripe
order are very subtle and the enhancement of the Nernst response due to static
stripe order in as compared to that of the
pseudogap phase in , if any, is very small.Comment: To appear in: 'Properties and applications of thermoelectric
materials - II', V. Zlatic and A. Hewson, editors, Proceedings of NATO
Advanced Research Workshop, Hvar, Croatia, September 19 -25, 2011, NATO
Science for Peace and Security Series B: Physics and Biophysics, (Springer
Science+Business Media B.V. 2012
Indikatoren für kooperative, online-basierte Lernprozesse: Entwicklung und Erprobung
Lernen als konstruktiver und sozialer Prozess funktioniert am besten in Interaktion mit anderen Personen. Insbesondere in online-basierten Lernsettings sind Interaktion und Kooperation der Studierenden ein wichtiger Faktor für erfolgreiches Lernen.
In dieser Arbeit schlagen wir zunächst Indikatoren für das Monitoring der Aktivität und Interaktivität von Studierenden sowie Lehrenden in kooperativen online-basierten Lernsettings vor. In einer Fallstudie werden die Indikatoren dann am Beispiel von drei Online-Kursen eingesetzt.
Die Ergebnisse zeigen, dass die Indikatoren wichtige Aufschlüsse über die Aktivität und Interaktivität der Studierenden liefern können. Ergänzt um Daten zur Arbeitsbelastung, um Prüfungsergebnisse und um Lehrevaluierungen können auch Aussagen zur Qualität der Lernprozesse und zum Lernerfolg gemacht werden
Nernst Effect of stripe ordering LaEuSrCuO
We investigate the transport properties of
LaEuSrCuO (, 0.08, 0.125, 0.15, 0.2) with a
special focus on the Nernst effect in the normal state. Various anomalous
features are present in the data. For and 0.15 a kink-like anomaly is
present in the vicinity of the onset of charge stripe order in the LTT phase,
suggestive of enhanced positive quasiparticle Nernst response in the stripe
ordered phase. At higher temperature, all doping levels except exhibit
a further kink anomaly in the LTO phase which cannot unambiguously be related
to stripe order. Moreover, a direct comparison between the Nernst coefficients
of stripe ordering LaEuSrCuO and superconducting
LaSrCuO at the doping levels and reveals
only weak differences. Our findings make high demands on any scenario
interpreting the Nernst response in hole-doped cuprates
Weak and strong electronic correlations in Fe superconductors
In this chapter the strength of electronic correlations in the normal phase
of Fe-superconductors is discussed. It will be shown that the agreement between
a wealth of experiments and DFT+DMFT or similar approaches supports a scenario
in which strongly-correlated and weakly-correlated electrons coexist in the
conduction bands of these materials. I will then reverse-engineer the realistic
calculations and justify this scenario in terms of simpler behaviors easily
interpreted through model results. All pieces come together to show that Hund's
coupling, besides being responsible for the electronic correlations even in
absence of a strong Coulomb repulsion is also the origin of a subtle emergent
behavior: orbital decoupling. Indeed Hund's exchange decouples the charge
excitations in the different Iron orbitals involved in the conduction bands
thus causing an independent tuning of the degree of electronic correlation in
each one of them. The latter becomes sensitive almost only to the offset of the
orbital population from half-filling, where a Mott insulating state is
invariably realized at these interaction strengths. Depending on the difference
in orbital population a different 'Mottness' affects each orbital, and thus
reflects in the conduction bands and in the Fermi surfaces depending on the
orbital content.Comment: Book Chapte
Electronic Raman scattering in YBCO and other superconducting cuprates
Superconductivity induced structures in the electronic Raman spectra of
high-Tc superconductors are computed using the results of ab initio LDA-LMTO
three-dimensional band structure calculations via numerical integrations of the
mass fluctuations, either in the whole 3D Brillouin zone or limiting the
integrations to the Fermi surface. The results of both calculations are rather
similar, the Brillouin zone integration yielding additional weak structures
related to the extended van Hove singularities. Similar calculations have been
performed for the normal state of these high-Tc cuprates. Polarization
configurations have been investigated and the results have been compared to
experimental spectra. The assumption of a simple d_(x^2-y^2)-like gap function
allows us to explain a number of experimental features but is hard to reconcile
with the relative positions of the A1g and B1g peaks.Comment: 14 pages, LaTeX (RevTeX), 5 PostScript figures, uses multicol.sty,
submitted to PR
Evidence for Magnetic Pseudoscaling in Overdoped La(2-x)Sr(x)CuO(4)
We report the results of electronic Raman scattering experiments on an
overdoped La(1.78)Sr(0.22)CuO(4) single crystal as a function of temperature.
The scattering rate Gamma(w->0,T) has been determined from the normal state
B(1g) spectra in the range 50 K < T < 300 K. Gamma(T) decreases linearly from
300 K to about 175 K and then undergoes a reduction with respect to the
expected mean-field behavior. This trend suggests a crossover to pseudoscaling
regime at about T(cr)=160 K. The results are in good agreement with the
prediction of the nearly antiferromagnetic Fermi liquid model. There is no
evidence of a pseudogap in the spectra obtained from this overdoped sample.Comment: RevTex, 4 pages with 3 PS figures included, replaced with minor
changes in the text and reference
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