Engineering topics
Publications and source records attributed to Goldberg, L..
Dynamic scene perception is currently limited to detection of moving objects from a static platform or scenes with flat backgrounds. We discuss novel methods to segment moving objects in the motion field formed by a moving camera/robotic platform in real time.
We report the generation of up to 0.7 mW of narrow-linewidth (<60-MHz) radiation at 3.3 micrometers by difference frequency mixing of a Nd:YAG-seeded 1.6-W Yb fiber amplifier and a 1.5-micrometers diode-laser-seeded 0.6-W Er/Yb fiber amplifier in periodically poled LiNbO3. A conversion efficiency of 0.09%/W (0.47 mWW-2 cm-1) was achieved. A room-air CH4 spectrum acquired with a compact 80-m multipass cell and a dual-beam spectroscopic configuration indicates an absorption sensitivity of +/-2.8 x 10(-5) (+/-1 sigma), corresponding to a sub-parts-in-10(9) (ppb) CH4 sensitivity (0.8 ppb).
Continuous-wave mid-infrared radiation near 3.5 micrometers is generated by difference-frequency mixing of the output of a compact 1.1-1.5 micrometer dual-wavelength fiber amplifier in periodically poled LiNbO3. The diode side-pumped amplifier is constructed with double-cladding Yb-doped fiber followed by single-mode Er/Yb codoped fiber. Output powers of as much as 11 microW at 3.4 micrometers are obtained, and spectroscopic detection of CH4 and H2CO is demonstrated. c 1998 Optical Society of America.
An optically activated switch was fabricated on LiNbO3 substrate by deposition of photoconductor-metal electrode structure on two channel waveguides obtained by the outdiffusion process. One waveguide was overcoated with a CdS film, and served as a light detector which converted the optical signal in that waveguide into an electric signal. Utilizing the electrooptic effect, this electric signal modulated the light propagating in the second waveguide by changing the refractive index, and the cutoff condition, of the waveguiding channel between two metal electrodes. The waveguides in the optically controlled switch can be either single or multimode. The length of the device can be short in comparison with other switching schemes. When binary optical signals are applied to the two waveguides, the switch can perform logic AND, NEGATION, OR and pseudo-amplification operations.
The Harvard experiment carried by OSO-6 was an extreme-ultraviolet (EUV) spectrometer-spectroheliometer with a wavelength range of 285 to 1385 A, a spatial and spectral bandwidth of 35 x 35(arc sec) squared and 3 A, respectively. The instrument acquired data that have been deposited with the National Space Science Data Center and World Data Center A at the Goddard Space Flight Center in Greenbelt, Maryland, and are now available in their entirety to the scientific community. Aspects of the experiment that are relevant to potential users of the data are described - namely, instrument configuration and parameters, laboratory and inflight calibrations, as well as operational capabilities and procedures. The observations obtained are reported, and the nature, number, and dates of observation, where relevant, are listed.
The preparation of a solar pointed spectrometer-spectroheliometer instrument for the orbiting solar observatory G is reported. This completes the documentation requirements with summaries of the hardware and post launch data analysis effects.
Photographic far UV solar spectra during eclipse of 7 March 1970, discussing coronal lines, prominences and quiet atmosphere structure
Detailed descriptions are given of research progress on theoretical, instrumental, and spectroscopic ultraviolet solar physics.
Discussion of the importance of laboratory and theoretical investigations for the analysis of solar UV and X-ray data by referring to five problems to which space experimenters are currently devoting a great deal of attention: (1) the temperature minimum at the interface between the photosphere and the chromosphere; (2) the temperature and density profiles of the low chromosphere; (3) the transition zone at the chromosphere-corona interface; (4) the corona; and (5) solar flares. Brief comments are made on the special need for laboratory and theoretical data of all kinds to assist in the interpretation of the rapidly accumulating volume of observations in the X-ray region of the solar spectrum.
Hydrogen I region anomalous alpha lines recombination in Orion B spectrum, identifying carbon emitter by measured frequency separation
Microwave recombination H lines, deriving electron temperature, electron density and emission measure sequentially
Planetary nebula NGC 7027, discussing hydrogen recombination lines
RF spectral recombination lines from atomic level transitions, discussing populations, H lines, electron temperature, density and emission and formation
Stimulated emission of RF recombination lines from ionized atoms in H I regions
IR emission in NGC 7027 spectrum and role of discrete line emissions, discussing magnetic dipole transitions, temperature and density
OSO-4 solar UV spectrum measurements, correlating chromospheric line intensity and photospheric magnetic field strengths
Thermal instability effects on radiative recombination line intensities under conditions in H 2 region
Population of atomic levels by cascade, dielectric and three-body electronic recombination, discussing spontaneous transition, electron impact and RF spectra