298,941 research outputs found
Matter Effects in Active-Sterile Solar Neutrino Oscillations
The matter effects for solar neutrino oscillations are studied in a general
scheme with an arbitrary number of sterile neutrinos, without any constraint on
the mixing, assuming only a realistic hierarchy of neutrino squared-mass
differences in which the smallest squared-mass difference is effective in solar
neutrino oscillations. The validity of the analytic results are illustrated
with a numerical solution of the evolution equation in three examples of the
possible mixing matrix in the simplest case of four-neutrino mixing.Comment: 26 pages. Final version published in Phys. Rev. D80 (2009) 11300
Evolutionary L∞ identification and model reduction for robust control
An evolutionary approach for modern robust control oriented system identification and model reduction in the frequency domain is proposed. The technique provides both an optimized nominal model and a 'worst-case' additive or multiplicative uncertainty bounding function which is compatible with robust control design methodologies. In addition, the evolutionary approach is applicable to both continuous- and discrete-time systems without the need for linear parametrization or a confined problem domain for deterministic convex optimization. The proposed method is validated against a laboratory multiple-input multiple-output (MIMO) test rig and benchmark problems, which show a higher fitting accuracy and provides a tighter L�¢���� error bound than existing methods in the literature do
Adiabatic passage of collective excitations in atomic ensembles
We describe a theoretical scheme that allows for transfer of quantum states
of atomic collective excitation between two macroscopic atomic ensembles
localized in two spatially-separated domains. The conception is based on the
occurrence of double-exciton dark states due to the collective destructive
quantum interference of the emissions from the two atomic ensembles. With an
adiabatically coherence manipulation for the atom-field couplings by stimulated
Ramann scattering, the dark states will extrapolate from an exciton state of an
ensemble to that of another. This realizes the transport of quantum information
among atomic ensembles.Comment: 7 pages, 2 figure
Implantable RF-coiled chip packaging
In this paper, we present an embedded chip integration
technology that utilizes silicon housings and flexible
parylene radio frequency (RF) coils. As a demonstration
of this technology, a flexible parylene RF coil has been
integrated with an RF identification (RFID) chip. The coil
has an inductance of 16 μH, with two layers of metal
completely encapsulated in parylene-C. The functionality
of the embedded chip is verified using an RFID reader
module. Accelerated-lifetime soak testing has been
performed in saline, and the results show that the silicon
chip is well protected and the lifetime of our
parylene-encapsulated RF coil at 37 °C is more than 20
years
- …