Abstract: A method of and system for monitoring the acoustic transmission conditions in underwater areas using an unmanned, mobile, submersible vehicle of the type including a source of acoustic signals. The submersible vehicle is controlled so that the vehicle traverses a desired path through the water of an area of interest. As the submersible vehicle traverses the desired path, a time-synchronized acoustic signal is transmitted from the acoustic source to at least one receiver spaced from the submersible vehicle so as to generate data representing the acoustic properties of the environment in the water between the acoustic source and the at least one receiver as the submersible vehicle traverses the desired path.

Abstract: Invention relates to a novel method of and system for ranging between an acoustic source carried on an unmanned or autonomous undersea mobile vehicle (UUV or AUV) and preferably a plurality of hydrophone receivers remotely deployed from the vehicle in predetermined patterns, generally suspended from sonobuoys equipped with above-the-sea relay radio transmitting antennas, and with time synchronization provided amongst the source and the receivers, wherein the time delay from the transmissions of the source is measured by utilizing special signal processing, enabling range to be measured in close to real time by determining the product of the sound velocity and the measured time delay, and with the process continually and periodically being repeated throughout the duration of the vehicle run.

Abstract: Polymers of glucaric or xylaric acid with diprimary amines containing at least one heteroatom in the main chain form films when cast from aqueous solution and show adhesive properties. Unexpectedly, analogous polymers prepared using galactaric acid, an isomer of glucaric acid, do not form satisfactory films when cast from aqueous solution and exhibit poor or no adhesive properties. Copoly(aldaramides) comprising galactaric acid residues and either glucaric acid or xylaric acid residues, when prepared by reacting an equivalent weight of an activated galactarate with a product formed by reaction of two equivalents of a diprimary heterohydrocarbylenediamine with one equivalent of either an activated xylarate or glucarate also afford film-forming polymers which exhibit adhesive properties.

Abstract: A single step process for converting aldaric acid salts to activated aldarates utilizing a lower alkanol as both solvent and esterifying agent is described. The activated aldarates are particularly useful as monomers for polymerizations with primary diamines in which the nitrogen atoms are bound to aliphatic carbon atoms to form poly(aldaramides).