16,634 research outputs found
Glass Ceiling Or Saran Wrapâą? Women In Gaming Management
This study explores women\u27s representation in gaming management in the 24 highest gross revenue gaming establishments in America. While almost 54% of foodservice and lodging employees are women, and approximately 44% of the managers in foodservice and lodging are women, one area of hospitality seems to be lagging-gaming. Our data indicated that women held 123 of 496 positions or 24.8% of casino management positions. Almost 68% of these female managers were in non-gaming positions. Our findings appear to support social closure theory since 11 of the 40 women in gaming management positions were in the cage department, and 4 of the 5 managers in Keno departments were women
In-situ growth optimization in focused electron-beam induced deposition
We present the application of an evolutionary genetic algorithm for the
in-situ optimization of nanostructures prepared by focused
electron-beam-induced deposition. It allows us to tune the properties of the
deposits towards highest conductivity by using the time gradient of the
measured in-situ rate of change of conductance as fitness parameter for the
algorithm. The effectiveness of the procedure is presented for the precursor
W(CO)6 as well as for post-treatment of Pt-C deposits obtained by dissociation
of MeCpPt(Me)3. For W(CO)6-based structures an increase of conductivity by one
order of magnitude can be achieved, whereas the effect for MeCpPt(Me)3 is
largely suppressed. The presented technique can be applied to all beam-induced
deposition processes and has great potential for further optimization or tuning
of parameters for nanostrucures prepared by FEBID or related techniques
Extending the Foundational Model of Anatomy with Automatically Acquired Spatial Relations
Formal ontologies have made significant impact in bioscience over the last ten years. Among them, the Foundational Model of Anatomy Ontology (FMA) is the most comprehensive model for the spatio-structural representation of human anatomy. In the research project MEDICO we use the FMA as our main source of background knowledge about human anatomy. Our ultimate goals are to use spatial knowledge from the FMA (1) to improve automatic parsing algorithms for 3D volume data sets generated by Computed Tomography and Magnetic Resonance Imaging and (2) to generate semantic annotations using the concepts from the FMA to allow semantic search on medical image repositories. We argue that in this context more spatial relation instances are needed than those currently available in the FMA. In this publication we present a technique for the automatic inductive acquisition of spatial relation instances by generalizing from expert-annotated volume datasets
Achieving diffraction-limited resolution in soft-X-ray Fourier-transform holography
The spatial resolution of microscopic images acquired via X-ray Fourier-transform holography is limited by the source size of the reference wave and by the numerical aperture of the detector. We analyze the interplay between both influences and show how they are matched in practice. We further identify, how high spatial frequencies translate to imaging artifacts in holographic reconstructions where mainly the reference beam limits the spatial resolution. As a solution, three methods are introduced based on numerical post-processing of the reconstruction. The methods comprise apodization of the hologram, refocusing via wave propagation, and deconvolution using the transfer function of the imaging system. In particular for the latter two, we demonstrate that image details smaller than the source size of the reference beam can be recovered up to the diffraction limit of the hologram. Our findings motivate the intentional application of a large reference-wave source enhancing the image contrast in applications with low photon numbers such as single-shot experiments at free-electron lasers or imaging at laboratory sources.BMBF, 05K10KTB, Verbundprojekt: FSP 301 - FLASH: Nanoskopische Systeme. Teilprojekt 1.1: Universelle Experimentierkammer fĂŒr Streuexperimente mit kohĂ€renten Femtosekunden-Röntgenpulsen Multi Purpose Coherent Scattering Chamber for FLASH and XFEL 'MPscatt
Controlling hole spin dynamics in twoâdimensional hole systems at low temperatures
With the recent discovery of very long hole spin decoherence times in GaAs/AlGaAs heterostructures of more than 70 ns
in two-dimensional hole systems, using the hole spin as a viable alternative to electron spins in spintronic applications seems
possible. Furthermore, as the hyperfine interaction with the nuclear spins is likely to be the limiting factor for electron spin
lifetimes in zero dimensions, holes with their suppressed Fermi contact hyperfine interaction due to their p-like nature should
be able to show even longer lifetimes than electrons. For spintronic applications, electric-field control of hole spin dynamics
is desirable.
Here, we report on time-resolved Kerr rotation and resonant spin amplification measurements on a two-dimensional hole
system in a p-doped GaAs/AlGaAs heterostructure. Via a semitransparent gate, we tune the charge density within the sample.
We are able to observe a change in the hole g factor, as well as in the hole spin dephasing time at high magnetic fields
Dynamics and decoherence in the central spin model using exact methods
The dynamics and decoherence of an electronic spin-1/2 qubit coupled to a
bath of nuclear spins via hyperfine interactions in a quantum dot is studied.
We show how exact results from the integrable solution can be used to
understand the dynamic behavior of the qubit. It is possible to predict the
main frequency contributions and their broadening for relatively general
initial states analytically, leading to an estimate of the corresponding decay
times. Furthermore, for a small bath polarization, a new low-frequency time
scale is observed.Comment: 4 pages, 2 figures. Published version. See also
http://www.physik.uni-kl.de/eggert/papers/index.htm
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