2,591 research outputs found
Image correlation and sampling study
The development of analytical approaches for solving image correlation and image sampling of multispectral data is discussed. Relevant multispectral image statistics which are applicable to image correlation and sampling are identified. The general image statistics include intensity mean, variance, amplitude histogram, power spectral density function, and autocorrelation function. The translation problem associated with digital image registration and the analytical means for comparing commonly used correlation techniques are considered. General expressions for determining the reconstruction error for specific image sampling strategies are developed
Noncommutative spin-1/2 representations
In this letter we apply the methods of our previous paper hep-th/0108045 to
noncommutative fermions. We show that the fermions form a spin-1/2
representation of the Lorentz algebra. The covariant splitting of the conformal
transformations into a field-dependent part and a \theta-part implies the
Seiberg-Witten differential equations for the fermions.Comment: 7 pages, LaTe
Ground state cooling of atoms in optical lattices
We propose two schemes for cooling bosonic and fermionic atoms that are
trapped in a deep optical lattice. The first scheme is a quantum algorithm
based on particle number filtering and state dependent lattice shifts. The
second protocol alternates filtering with a redistribution of particles by
means of quantum tunnelling. We provide a complete theoretical analysis of both
schemes and characterize the cooling efficiency in terms of the entropy. Our
schemes do not require addressing of single lattice sites and use a novel
method, which is based on coherent laser control, to perform very fast
filtering.Comment: 12 pages, 7 figure
IR-Singularities in Noncommutative Perturbative Dynamics?
We analyse the IR-singularities that appear in a noncommutative scalar
quantum field theory on . We demonstrate with the help of the
quadratic one-loop effective action and an appropriate field redefinition that
no IR-singularities exist. No new degrees of freedom are needed to describe the
UV/IR-mixing.Comment: 6 pages, amsLaTe
Noncommutative Lorentz Symmetry and the Origin of the Seiberg-Witten Map
We show that the noncommutative Yang-Mills field forms an irreducible
representation of the (undeformed) Lie algebra of rigid translations, rotations
and dilatations. The noncommutative Yang-Mills action is invariant under
combined conformal transformations of the Yang-Mills field and of the
noncommutativity parameter \theta. The Seiberg-Witten differential equation
results from a covariant splitting of the combined conformal transformations
and can be computed as the missing piece to complete a covariant conformal
transformation to an invariance of the action.Comment: 20 pages, LaTeX. v2: Streamlined proofs and extended discussion of
Lorentz transformation
Autofluorescence lifetime augmented reality as a means for real-time robotic surgery guidance in human patients.
Due to loss of tactile feedback the assessment of tumor margins during robotic surgery is based only on visual inspection, which is neither significantly sensitive nor specific. Here we demonstrate time-resolved fluorescence spectroscopy (TRFS) as a novel technique to complement the visual inspection of oral cancers during transoral robotic surgery (TORS) in real-time and without the need for exogenous contrast agents. TRFS enables identification of cancerous tissue by its distinct autofluorescence signature that is associated with the alteration of tissue structure and biochemical profile. A prototype TRFS instrument was integrated synergistically with the da Vinci Surgical robot and the combined system was validated in swine and human patients. Label-free and real-time assessment and visualization of tissue biochemical features during robotic surgery procedure, as demonstrated here, not only has the potential to improve the intraoperative decision making during TORS but also other robotic procedures without modification of conventional clinical protocols
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