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Creative Information Exploration in Journalism
Existing digital tools used by journalists such as content management systems and search engines focus on helping journalists find relevant information and organize their creative work; they do not provide support for discovering creative angles to investigate. To meet this need in journalism, we have researched new creative search algorithms that manipulate the journalist’s primary medium – written information – and developed an innovative creativity and productivity support tool deliberately for use by journalists. In this paper, we analyse the creative tasks journalists perform when developing new stories, we provide an overview of requirements, which have been addressed by the INJECT digital creativity support tool for journalists. Further, we explain the intended use of the system using a walkthrough scenario and present our early experiences from deploying the tool in journalist’s working environments
Evidences for Tsallis non-extensivity on CMR manganites
We found, from the analysis of vs. curves of some manganese oxides
(manganites), that these systems do not follow the traditional
Maxwell-Boltzmann statistics, but the Tsallis statistics, within the
\QTR{em}{normalized} formalism. Curves were calculated within the mean field
approximation, for various ferromagnetic samples and the results were compared
to measurements of our own and to various other authors published data, chosen
at random from the literature. The agreement between the experimental data and
calculated vs. curve, where is an effective
temperature, is excellent for all the compounds. The entropic parameter, ,
correlates in a simple way with the experimental value of , irrespect
the chemical composition of the compounds, heat treatment or other details on
sample preparation. Examples include (superextensivity),
(extensivity) and (subextensivity) cases.Comment: 12 pages, 3 figure
Interplay of superexchange and orbital degeneracy in Cr-doped LaMnO3
We report on structural, magnetic and Electron Spin Resonance (ESR)
investigations in the manganite system LaMn_{1-x}Cr_{x}O_{3} (x<=0.5). Upon
Cr-doping we observe a reduction of the Jahn-Teller distortion yielding less
distorted orthorhombic structures. A transition from the Jahn-Teller distorted
O' to the pseudocubic O phase occurs between 0.3<x<0.4. A clear connection
between this transition and the doping dependence of the magnetic and ESR
properties has been observed. The effective moments determined by ESR seem
reduced with respect to the spin-only value of both Mn^{3+} and Cr^{3+} ions
Structural, magnetic and electrical properties of single crystalline La_(1-x)Sr_xMnO_3 for 0.4 < x < 0.85
We report on structural, magnetic and electrical properties of Sr-doped
LaMnO_3 single crystals for doping levels 0.4 < x < 0.85. The complex
structural and magnetic phase diagram can only be explained assuming
significant contributions from the orbital degrees of freedom. Close to x = 0.6
a ferromagnetic metal is followed by an antiferromagnetic metallic phase below
200 K. This antiferromagnetic metallic phase exists in a monoclinic
crystallographic structure. Following theoretical predictions this metallic
antiferromagnet is expected to reveal an (x^2-y^2)-type orbital order. For
higher Sr concentrations an antiferromagnetic insulator is established below
room temperature.Comment: 8 pages, 7 figure
Crystal Field and Dzyaloshinsky-Moriya Interaction in orbitally ordered La_{0.95}Sr_{0.05}MnO_3: An ESR Study
We present a comprehensive analysis of Dzyaloshinsky-Moriya interaction and
crystal-field parameters using the angular dependence of the paramagnetic
resonance shift and linewidth in single crystals of La_{0.95}Sr_{0.05}MnO_3
within the orthorhombic Jahn-Teller distorted phase. The Dzyaloshinsky-Moriya
interaction (~ 1K) results from the tilting of the MnO_6 octahedra against each
other. The crystal-field parameters D and E are found to be of comparable
magnitude (~ 1K) with D ~= -E. This indicates a strong mixing of the |3z^2-r^2>
and |x^2-y^2> states for the real orbital configuration.Comment: 12 pages, 6 figure
A Detailed XRD and FTIR Analysis of Bi2O3 Doped ZnO-SnO2 Ceramics
Poster presented at the 2nd International Congress on Ceramics, Verona, Italy, June 29 - July 4, 200
Changes of Structural, Optical and Electrical Properties of Nickel-Manganite Ceramics Induced by Additional Mechanical Activation
Poster presented at the 10th International Conference and Exhibition of the European Ceramic Society, Berlin, June 17-21, 200
Effect of transport-induced charge inhomogeneity on point-contact Andreev reflection spectra at ferromagnet-superconductor interfaces
We investigate the transport properties of a ferromagnet-superconductor
interface within the framework of a modified three-dimensional
Blonder-Tinkham-Klapwijk formalism. In particular, we propose that charge
inhomogeneity forms via two unique transport mechanisms, namely, evanescent
Andreev reflection and evanescent quasiparticle transmission. Furthermore, we
take into account the influence of charge inhomogeneity on the interfacial
barrier potential and calculate the conductance as a function of bias voltage.
Point-contact Andreev reflection (PCAR) spectra often show dip structures,
large zero-bias conductance enhancement, and additional zero-bias conductance
peak. Our results indicate that transport-induced charge inhomogeneity could be
a source of all these anomalous characteristics of the PCAR spectra.Comment: 9 pages, 6 figure
Formalising the Continuous/Discrete Modeling Step
Formally capturing the transition from a continuous model to a discrete model
is investigated using model based refinement techniques. A very simple model
for stopping (eg. of a train) is developed in both the continuous and discrete
domains. The difference between the two is quantified using generic results
from ODE theory, and these estimates can be compared with the exact solutions.
Such results do not fit well into a conventional model based refinement
framework; however they can be accommodated into a model based retrenchment.
The retrenchment is described, and the way it can interface to refinement
development on both the continuous and discrete sides is outlined. The approach
is compared to what can be achieved using hybrid systems techniques.Comment: In Proceedings Refine 2011, arXiv:1106.348
The Orbital Order Parameter in La0.95Sr0.05MnO3 probed by Electron Spin Resonance
The temperature dependence of the electron-spin resonance linewidth in
La0.95Sr0.05MnO3 has been determined and analyzed in the paramagnetic regime
across the orbital ordering transition. From the temperature dependence and the
anisotropy of linewidth and -value the orbital order can be unambiguously
determined via the mixing angle of the wave functions of the -doublet. The linewidth shows a similar evolution with temperature as
resonant x-ray scattering results
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