Time-Dependent Inverse Methods for Finding Currents and Initial Conditions Which Lead to Prescribed Signals

Abstract

The principal research accomplishment during the period of the grant was the study of generation of acoustic pulses from electromagnetic pulses. In particular, we considered an infinite medium, which we took to be a non- conducting liquid (ultimately we chose water for numerical examples) and assumed that a one-dimensional and electromagnetic pulse or train of pulses was created at time t=O by the turning on and off of appropriate currents and found the acoustic pulses which were generated by the electromagnetic pulses. Indications are that if the electromagnetic pulse is sufficiently strong, the acoustic pulse which is generated can have significant physiological effects, if the liquid, say water, is assumed to model a tissue. We have also investigated the mathematics of the Radon transform with the view to using it to obtain the exact time-dependent acoustic and electromagnetic fields from the fields in the wave zone. The applications are many, but the use in aerospace medicine includes the monitoring of acoustic and electromagnetic fields at a distance from the source and determining the fields near the source. Another area of research has been the time-dependent propagation of one dimensional electromagnetic pulses through slabs and media with continuously varying index of refraction, possibly with jumps.

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Document Details

Document Type
Technical Report
Publication Date
Jun 30, 1987
Accession Number
ADA182806

Entities

People

  • Harry E. Moses

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Aerospace Medicine
  • Air Force
  • Availability
  • Classification
  • Demographic Cohorts
  • Electrical Engineering
  • Electromagnetic Fields
  • Electromagnetic Pulses
  • Engineering
  • Massachusetts
  • Monitoring
  • Physiological Effects
  • Refraction
  • Refractive Index
  • Universities

Fields of Study

  • Physics

Readers

  • Calculus or Mathematical Analysis
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Optical Physics and Photonics.

Technology Areas

  • Space