5,092 research outputs found
Polynomial-Time Solution to the Hidden Subgroup Problem for a Class of non-abelian Groups
We present a family of non-abelian groups for which the hidden subgroup
problem can be solved efficiently on a quantum computer.Comment: 16 pages, LaTeX2e, 3 figure
Matroids with nine elements
We describe the computation of a catalogue containing all matroids with up to
nine elements, and present some fundamental data arising from this cataogue.
Our computation confirms and extends the results obtained in the 1960s by
Blackburn, Crapo and Higgs. The matroids and associated data are stored in an
online database, and we give three short examples of the use of this database.Comment: 22 page
A Spectral-Scanning Nuclear Magnetic Resonance Imaging (MRI) Transceiver
An integrated spectral-scanning nuclear magnetic resonance imaging (MRI) transceiver is implemented in a 0.12 mum SiGe BiCMOS process. The MRI transmitter and receiver circuitry is designed specifically for small-scale surface MRI diagnostics applications where creating low (below 1 T) and inhomogeneous magnetic field is more practical. The operation frequency for magnetic resonance detection and analysis is tunable from 1 kHz to 37 MHz, corresponding to 0-0.9 T magnetization for ^1H (hydrogen). The concurrent measurement bandwidth is approximately one frequency octave. The chip can also be used for conventional narrowband nuclear magnetic resonance (NMR) spectroscopy from 1 kHz up to 250 MHz. This integrated transceiver consists of both the magnetic resonance transmitter which generates the required excitation pulses for the magnetic dipole excitation, and the receiver which recovers the responses of the dipoles
Spanning Trees in Graphs of High Minimum Degree with a Universal Vertex I: An Approximate Asymptotic Result
In this paper and a companion paper, we prove that, if is sufficiently
large, every graph on vertices that has a universal vertex and minimum
degree at least contains each tree with
edges as a subgraph. The present paper already contains an approximate
asymptotic version of the result.
Our result confirms, for large , an important special case of a recent
conjecture by Havet, Reed, Stein, and Wood.Comment: 46 page
The development of a power spectral density processor for C and L band airborne radar scatterometer sensor systems
A real-time signal processor was developed for the NASA/JSC L-and C-band airborne radar scatterometer sensor systems. The purpose of the effort was to reduce ground data processing costs. Conversion of two quadrature channels of data (like and cross polarized) was made to obtain Power Spectral Density (PSD) values. A chirp-z transform (CZT) approach was used to filter the Doppler return signal and improved high frequency and angular resolution was realized. The processors have been tested with record signals and excellent results were obtained. CZT filtering can be readily applied to scatterometers operating at other wavelengths by altering the sample frequency. The design of the hardware and software and the results of the performance tests are described in detail
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