31,834 research outputs found
CVT/GPL phase 3 integrated testing
The hardware for 20 candidate shuttle program life sciences experiments was installed in the GPL and experiments were conducted during a 5-day simulated mission. The experiments involved humans, primates, rats, chickens, and marigold plants. All experiments were completed to the satisfaction of the experimenters. In addition to the scientific data gathered for each experiment, information was obtained concerning experiment hardware design and integration, experiment procedures, GPL support systems, and test operations. The results of the integrated tests are presented
Multi-view 3D retrieval using silhouette intersection and multi-scale contour representation
We describe in this paper two methods for 3D shape indexing
and retrieval that we apply on two data collections
of the SHREC - SHape Retrieval Contest 2007: Watertight
models and 3D CAD models. Both methods are based on a
set of 2D multi-views after a pose and scale normalization
of the models using PCA and the enclosing sphere. In all
views we extract the models silhouettes and compare them
pairwise. In the first method the similitude measure is obtained by integrating on the pairs of views the difference between the areas of the silhouettes union and the silhouettes intersection. In the second method we consider the external contour of the silhouettes, extract their convexities and concavities at different scale levels and build a multiscale representation. The pairs of contours are then compared by elastic matching achieved by using dynamic programming. Comparisons of the two methods are shown with their respective strengths and weaknesses
Canonical Transformation Approach to the Ultrafast Non-linear Optical Dynamics of Semiconductors
We develop a theory describing the effects of many-particle Coulomb
correlations on the coherent ultrafast nonlinear optical response of
semiconductors and metals. Our approach is based on a mapping of the nonlinear
optical response of the ``bare'' system onto the linear response of a
``dressed'' system. The latter is characterized by effective time-dependent
optical transition matrix elements, electron/hole dispersions, and interaction
potentials, which in undoped semiconductors are determined by the
single-exciton and two-exciton Green functions in the absence of optical
fields. This mapping is achieved by eliminating the optically-induced charge
fluctuations from the Hamiltonian using a Van Vleck canonical transformation.
It takes into account all many-body contributions up to a given order in the
optical fields as well as important Coulomb-induced quantum dynamics to all
orders in the optical field. Our approach allows us to distinguish between
optical nonlinearities of different origins and provides a physically-intuitive
interpretation of their manifestations in ultrafast coherent nonlinear optical
spectroscopy.Comment: 24 page
"Strongly interacting matter in magnetic fields": an overview
This is an introduction to the volume of Lecture Notes in Physics on
"Strongly interacting matter in magnetic fields". The volume combines
contributions written by a number of experts on different aspects of the
problem. The response of QCD matter to intense magnetic fields has attracted a
lot of interest recently. On the theoretical side, this interest stems from the
possibility to explore the plethora of novel phenomena arising from the
interplay of magnetic field with QCD dynamics. On the experimental side, the
interest is motivated by the recent results on the behavior of quark-gluon
plasma in a strong magnetic field created in relativistic heavy ion collisions
at RHIC and LHC. The purpose of this introduction is to provide a brief
overview and a guide to the individual contributions where these topics are
covered in detail.Comment: 12 pages, introduction to "Strongly interacting matter in magnetic
fields", Lect. Notes Phys. 871, 1 (2013), edited by D. Kharzeev, K.
Landsteiner, A. Schmitt, H.-U. Yee; v2: references update
Adaptive computing techniques
Adaptive local algorithm and convergence speed of multimodal multidimensional functio
Saunders, Harold H.A Public Peace Process: Sustained Dialogue to Transform Racial and Ethnic Conflict.New York: St. Martin's Press, 1999.
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