2,235 research outputs found
Kinematic sensitivity of robot manipulators
Kinematic sensitivity vectors and matrices for open-loop, n degrees-of-freedom manipulators are derived. First-order sensitivity vectors are defined as partial derivatives of the manipulator's position and orientation with respect to its geometrical parameters. The four-parameter kinematic model is considered, as well as the five-parameter model in case of nominally parallel joint axes. Sensitivity vectors are expressed in terms of coordinate axes of manipulator frames. Second-order sensitivity vectors, the partial derivatives of first-order sensitivity vectors, are also considered. It is shown that second-order sensitivity vectors can be expressed as vector products of the first-order sensitivity vectors
Elastic and Diffractive Scattering after AdS/CFT
At high energies, elastic hadronic cross sections are believed to be
dominated by vacuum exchange. In leading order of the leading expansion
this exchange process has been identified as the BFKL {\em Pomeron} or its
strong AdS dual the closed string graviton \cite{Brower:2006ea}. However
difference of particle anti-particle cross sections are given by a so-called
{\em Odderon} carrying C = -1 quantum numbers identified in weak coupling with
odd numbers of exchanged gluons. Here we show that the dual description
associates this with the Neveu-Schwartz () sector of closed string
theory. We also discuss the extension of the strong coupling treatment to
central diffractive Higgs production at LHC.Comment: 7 pages, 3 figures; presented at International Conference on Elastic
and Diffractive Scattering, EDS'09, CERN, July 3, 200
Saturation and Confinement: Analyticity, Unitarity and AdS/CFT Correspondence
In expansion, analyticity and crossing lead to crossing even and odd
() vacuum exchanges at high-energy, the {\em Pomeron} and the {\em
Odderon}. We discuss how, using {\em String/Gauge duality}, these can be
identified with a reggeized {\em Graviton} and the anti-symmetric {\em
Kalb-Ramond fields} in background. With confinement, these Regge
singularities interpolate with glueball states. We also discuss unitarization
based on eikonal sum in .Comment: more references added. presented at ISMD 2008, 15-20 Sept. 200
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