Interactive digital signal processor

The Interactive Digital Signal Processor (IDSP) is examined. It consists of a set of time series analysis Operators each of which operates on an input file to produce an output file. The operators can be executed in any order that makes sense and recursively, if desired. The operators are the various algorithms used in digital time series analysis work. User written operators can be easily interfaced to the sysatem. The system can be operated both interactively and in batch mode. In IDSP a file can consist of up to n (currently n=8) simultaneous time series. IDSP currently includes over thirty standard operators that range from Fourier transform operations, design and application of digital filters, eigenvalue analysis, to operators that provide graphical output, allow batch operation, editing and display information

Algebraic geometric methods for the stabilizability and reliability of multivariable and of multimode systems

The extent to which feedback can alter the dynamic characteristics (e.g., instability, oscillations) of a control system, possibly operating in one or more modes (e.g., failure versus nonfailure of one or more components) is examined

Preliminary Analysis of the Metabolic Rate Monitor System

Metabolic rate monitor system analysi

An Application of Feynman-Kleinert Approximants to the Massive Schwinger Model on a Lattice

A trial application of the method of Feynman-Kleinert approximants is made to perturbation series arising in connection with the lattice Schwinger model. In extrapolating the lattice strong-coupling series to the weak-coupling continuum limit, the approximants do not converge well. In interpolating between the continuum perturbation series at large fermion mass and small fermion mass, however, the approximants do give good results. In the course of the calculations, we picked up and rectified an error in an earlier derivation of the continuum series coefficients.Comment: 16 pages, 4 figures, 5 table

Coincident Measurement of the Energy Spectra of Doppler-Shifted Annihilation Gamma Quanta and Positron-Induced Secondary Electrons

Preliminary results are presented from a new positron beam system currently under development at the University of Texas at Arlington for the coincident energy measurement of Doppler-shifted annihilation quanta and positron-induced Auger electrons. We report data based on an analysis of the pulses resulting from the detection of positron induced secondary electrons by a micro-channel plate detector in coincidence with the pulses resulting from the detection of associated annihilation gamma rays in a NaI(Tl) gamma detector.Comment: Presented at 18th International Conference on Positron Annihilation, August 19-24, 2018 | Orlando, USA. The following article has been accepted by AIP Conference Proceedings. After it is published, it will be found at https://aip.scitation.org/journal/ap

Enhancement factor for the electron electric dipole moment in francium and gold atoms

If electrons had an electric dipole moment (EDM) they would induce EDMs of atoms. The ratio of the atomic EDM to the electron EDM for a particular atom is called the enhancement factor, R. We calculate the enhancement factor for the francium and gold atoms, with the results 910 plus/minus 5% for Fr and 260 plus/minus 15% for Au. The large values of these enhancement factors make these atoms attractive for electron EDM measurements, and hence the search for time-reversal invariance violation.Comment: 6 pages, no figures, uses RevTex, reference adde

One and Two Dimensional Spin Systems in the Regime Close to Deconfinement of Spinons

Based on the Majumdar-Ghosh chain we construct several spin models which allow us to investigate spinon dynamics in the regime close to deconfinement of spinons. We consider the J_1 - J_2 - \delta model, two coupled J_1 - J_2 chains (ladder), and a 2D array of coupled J_1 - J_2 chains. Using the picture of two spinons interacting with a string confining potential we calculate the singlet- triplet splitting, magnetic structure factor, tunneling amplitude of two spinons and the excitation spectra for the ladder and the array.Comment: 12 pages, 16 figures (2 eps figures