This thesis is an experimental study of an acoustic
surface wave delay line using a Lithium Niobate crystal.
A brief theory of operation of the interdigital transducer
with its advantages over the other methods of exciting and
detecting acoustic surface waves is discussed. The experimental
procedure used for evaluation of...
The communicative behavior of five species and subspecies of
Tropisternus Solier (Coleoptera: Hydrophilidae) was studied. These
aquatic beetles have stress and calling chirps (both sexes), a second
male calling signal (one species), a single male courtship sound
(usually), a male copulatory sound, and a female aggressive rejection
buzz (three species)....
Three sympatric species of Ips, colonizing Sitka spruce, were
investigated with regard to their infestation habits, stridulating
apparatus and acoustic signals. The above phenomena are evaluated
qualitatively and/or quantitatively and the acoustic signal differences
are proposed as a possible factor for maintaining species isolation,
although function is not shown.
Field...
The effects of discharged sewage on physico-chemical conditions
and the distribution and abundance of marine benthic animals were
studied in Shilshole Bay, a part of Puget Sound, off Seattle,
Washington. For over 50 years prior to 1965, when this study was
initiated, 87,300 pounds (32,400 pounds BOD) per day of...
Current observations were obtained at three locations forming
a cross section along 70°34'W longitude in Long Island Sound. Fifteen
days of data were selected from each series so that nearly
simultaneous observations were used in the analysis.
Elementary statistics were computed for the data prior to
performing a least squares...