12,730,903 research outputs found
Ratemeter
An instantaneous reading tachometer in which reoccurring events to be measured in rate, trigger a threestate timing generator in which the first two states are of fixed duration and the third state is of variable duration is described. An electrical decay circuit is set to a reference level by the second state and the third state causes this reference level to decay until the reoccurrence of an event. This triggers a new first state which in turn triggers a sample and hold circuit to hold the decayed level. The decayed level is amplified and provided as an output indicative of the instantaneous rate of occurence of the last two successive events
Cubic interaction vertices for fermionic and bosonic arbitrary spin fields
Using the light-cone gauge approach to relativistic field dynamics, we study
arbitrary spin fermionic and bosonic fields propagating in flat space of
dimension greater than or equal to four. Generating functions of parity
invariant cubic interaction vertices for totally symmetric and mixed-symmetry
massive and massless fields are obtained. For the case of totally symmetric
fields, we derive restrictions on the allowed values of spins and the number of
derivatives. These restrictions provide a complete classification of parity
invariant cubic interaction vertices for totally symmetric fermionic and
bosonic fields. As an example of application of the light-cone formalism, we
obtain simple expressions for the Yang-Mills and gravitational interactions of
massive arbitrary spin fermionic fields. For some particular cases, using our
light-cone cubic vertices, we discuss the corresponding manifestly Lorentz
invariant and on-shell gauge invariant cubic vertices.Comment: 57 pages, LaTeX-2e. v2: Results and conclusions of version v1
unchanged. New results for cubic vertices of mixed-symmetry fields added.
Appendix A fully rewritten. Typos corrected. References added. arXiv admin
note: significant text overlap with arXiv:hep-th/051234
A long-lived precision switch actuator for controlling pump-piston action
Switch mechanism limits the stroke of the piston by stopping the piston motor drive. This allows retention of a fluid sample in an automated wet-chemical analysis system
Solar cell including second surface mirrors Patent
Modifying existing solar cells for temperature contro
Geometrically Intrinsic Nonlinear Recursive Filters I: Algorithms
The Geometrically Intrinsic Nonlinear Recursive Filter, or GI Filter, is
designed to estimate an arbitrary continuous-time Markov diffusion process X
subject to nonlinear discrete-time observations. The GI Filter is fundamentally
different from the much-used Extended Kalman Filter (EKF), and its second-order
variants, even in the simplest nonlinear case, in that: (i) It uses a quadratic
function of a vector observation to update the state, instead of the linear
function used by the EKF. (ii) It is based on deeper geometric principles,
which make the GI Filter coordinate-invariant. This implies, for example, that
if a linear system were subjected to a nonlinear transformation f of the
state-space and analyzed using the GI Filter, the resulting state estimates and
conditional variances would be the push-forward under f of the Kalman Filter
estimates for the untransformed system - a property which is not shared by the
EKF or its second-order variants.
The noise covariance of X and the observation covariance themselves induce
geometries on state space and observation space, respectively, and associated
canonical connections. A sequel to this paper develops stochastic differential
geometry results - based on "intrinsic location parameters", a notion derived
from the heat flow of harmonic mappings - from which we derive the
coordinate-free filter update formula. The present article presents the
algorithm with reference to a specific example - the problem of tracking and
intercepting a target, using sensors based on a moving missile. Computational
experiments show that, when the observation function is highly nonlinear, there
exist choices of the noise parameters at which the GI Filter significantly
outperforms the EKF.Comment: 22 pages, 4 figure
Baseline Cold Matter Effects on J/psi Production in AA Collisions
We present baseline calculations of initial-state shadowing and final-state
absorption effects on J/psi production in nucleus-nucleus collisions at the
Relativistic Heavy Ion Collider. We show predictions for Au+Au and Cu+Cu
collisions at \sqrt{S_{NN}}=200 GeV and Cu+Cu collisions at \sqrt{S_{NN}} = 62
GeV as a function of the rapidity, y, and the number of binary nucleon-nucleon
collisions, N_{\rm coll}.Comment: 7 pages, 4 figures, uses hiph-art.sty, one figure replaced, some
corrections to tex
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