3,134 research outputs found
Miniature capacitive accelerometer is especially applicable to telemetry
Capacitive accelerometer design enables the construction of highly miniaturized instruments having full-scale ranges from 1 g to several hundred g. This accelerometer is applicable to telemetry and can be tailored to cover any of a large number of acceleration ranges and frequency responses
Estimation of Farmland Values for Assessment and Property Taxation in North Dakota
Land Economics/Use,
Vector Meson Dominance and Rho-Omega Mixing
The scale of a phenomenologically successful charge-symmetry-violating
nucleon-nucleon interaction, that attributed to meson exchange with a rho-omega transition, is set by the Coleman-Glashow SU(2) breaking tadpole
mechanism. A single tadpole scale has been obtained from symmetry arguments,
electromagnetic meson and baryon measured mass splittings, and the observed
isospin violating () decay . The hadronic
realization of this tadpole mechanism lies in the scalar meson.
We show that measured hadronic and two-photon widths of the meson, with
the aid of the Vector Meson Dominance model, recover the universal
Coleman-Glashow tadpole scale.Comment: 18 pages, 2 figures, to appear in Physical Review
Parallel asynchronous systems and image processing algorithms
A new hardware approach to implementation of image processing algorithms is described. The approach is based on silicon devices which would permit an independent analog processing channel to be dedicated to evey pixel. A laminar architecture consisting of a stack of planar arrays of the device would form a two-dimensional array processor with a 2-D array of inputs located directly behind a focal plane detector array. A 2-D image data stream would propagate in neuronlike asynchronous pulse coded form through the laminar processor. Such systems would integrate image acquisition and image processing. Acquisition and processing would be performed concurrently as in natural vision systems. The research is aimed at implementation of algorithms, such as the intensity dependent summation algorithm and pyramid processing structures, which are motivated by the operation of natural vision systems. Implementation of natural vision algorithms would benefit from the use of neuronlike information coding and the laminar, 2-D parallel, vision system type architecture. Besides providing a neural network framework for implementation of natural vision algorithms, a 2-D parallel approach could eliminate the serial bottleneck of conventional processing systems. Conversion to serial format would occur only after raw intensity data has been substantially processed. An interesting challenge arises from the fact that the mathematical formulation of natural vision algorithms does not specify the means of implementation, so that hardware implementation poses intriguing questions involving vision science
Parallel asynchronous hardware implementation of image processing algorithms
Research is being carried out on hardware for a new approach to focal plane processing. The hardware involves silicon injection mode devices. These devices provide a natural basis for parallel asynchronous focal plane image preprocessing. The simplicity and novel properties of the devices would permit an independent analog processing channel to be dedicated to every pixel. A laminar architecture built from arrays of the devices would form a two-dimensional (2-D) array processor with a 2-D array of inputs located directly behind a focal plane detector array. A 2-D image data stream would propagate in neuron-like asynchronous pulse-coded form through the laminar processor. No multiplexing, digitization, or serial processing would occur in the preprocessing state. High performance is expected, based on pulse coding of input currents down to one picoampere with noise referred to input of about 10 femtoamperes. Linear pulse coding has been observed for input currents ranging up to seven orders of magnitude. Low power requirements suggest utility in space and in conjunction with very large arrays. Very low dark current and multispectral capability are possible because of hardware compatibility with the cryogenic environment of high performance detector arrays. The aforementioned hardware development effort is aimed at systems which would integrate image acquisition and image processing
Benchmark calculations for polarization observables in 3N scattering
High precision benchmark calculations for phase-shifts and mixing parameters
as well as observables in elastic neutron-deuteron scattering below the
deuteron breakup threshold are presented using a realistic nucleon-nucleon
potential. Two totally different methods, one using a variational principle in
configuration space and the other solving the Faddeev equations in momentum
space are used and compared to each other. The agreement achieved in
phase-shifts and mixing parameters as well as in the polarization observables
is excellent. The extreme sensitivity of the vector analyzing power Ay to small
changes of the phase shifts and mixing parameters is pointed out.Comment: 22 pages, 5 postscript figure
Meson PVV Interactions are determined by Quark Loops
We show that all abnormal parity three-body meson interactions can be
adequately described by quark loops, evaluated at zero external momentum, with
couplings determined by symmetry. We focus primarily on radiative
meson decays which involve one pseudoscalar. The agreement with experiment for
non-rare decays is surprisingly good and requires very few parameters, namely
the coupling constants and and some mixing angles.
This agreement extends to some three-body decays that are dominated by pion
pairs in a P-wave state.Comment: 21 pages, Revtex, one figur
INTEREST MARGIN AND AGRICULTURAL BANK PERFORMANCE: A PRELIMINARY ANALYSIS
Agricultural Finance,
q-Boson approach to multiparticle correlations
An approach is proposed enabling to effectively describe, for relativistic
heavy-ion collisions, the observed deviation from unity of the intercept
\lambda (measured value corresponding to zero relative momentum {\bf p} of two
registered identical pions or kaons) of the two-particle correlation function
C(p,K). The approach uses q-deformed oscillators and the related picture of
ideal gas of q-bosons. In effect, the intercept \lambda is connected with
deformation parameter q. For a fixed value of q, the model predicts specific
dependence of \lambda on pair mean momentum {\bf K} so that, when |{\bf
K}|\gsim 500 - 600 MeV/c for pions or when |{\bf K}|\gsim 700 - 800 MeV/c for
kaons, the intercept \lambda tends to a constant which is less than unity and
determined by q. If q is fixed to be the same for pions and kaons, the
intercepts \lambda_\pi and \lambda_K essentially differ at small mean momenta
{\bf K}, but tend to be equal at {\bf K} large enough (|{\bf K}|\gsim 800MeV/c)
where the effect of resonance decays can be neglected. We argue that it is of
basic interest to check in the experiments on heavy ion collisions: (i) the
exact shape of dependence \lambda = \lambda({\bf K}), and (ii) whether for
|{\bf K}| \gsim 800 MeV/c the resulting \lambda_\pi and \lambda_K indeed
coincide.Comment: 6 pages, revtex, 4 figures, to be published in Mod. Phys. Lett.
Momentum and Coordinate Space Three-nucleon Potentials
In this paper we give explicit formulae in momentum and coordinate space for
the three-nucleon potentials due to and meson exchange, derived
from off-mass-shell meson-nucleon scattering amplitudes which are constrained
by the symmetries of QCD and by the experimental data. Those potentials have
already been applied to nuclear matter calculations. Here we display additional
terms which appear to be the most important for nuclear structure. The
potentials are decomposed in a way that separates the contributions of
different physical mechanisms involved in the meson-nucleon amplitudes. The
same type of decomposition is presented for the TM force: the
, the chiral symmetry breaking and the nucleon pair terms are isolated.Comment: LATEX, 33 pages, 3 figures (available as postscript files upon
request
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