OLR (1988) 35 (9) G. New Patents 863

This Section contains abstracts and, where appropriate, illustrations of recently issued United States patents and published patent applications filed from over 30 countries under the Patent Cooperation Treaty. This information was obtained from recent additions to the Pergamon PATSEARCH ® online database in accordance with interest profiles developed by the Editors. Further information about Pergamon PATSEARCH ® can be obtained from Pergamon Orbit InfoLine Inc., 8000 Westpark Drive, McLean, Virginia 22102 U.S.A.

Copies of complete patents announced in this Section are available from Pergamon Orbit InfoLine Inc. for $8 per copy. Payment with order is required. Orders outside North America add $2 for air postage. Order by patent number for Pergamon Orbit InfoLine only.

4733378 4739579

ACTIVE LOW-PROFILE HYDROPHONE

Richard Pearce, Richard Marschall, James Brown assigned to Western Atlas International Inc

An active, low-profile hydrophone for use in aquatic environments having substantially tur- bulent flow conditions. The hydrophone is gene- rally pisciform such that it may lie substantially fiat on the water bottom and oriented in the cur- rent so as to reduce ambient noise associated with the turbulent flow. The enclosed sensors are oriented such that they are insensitive to ac- celeration and are coupled to a unity gain am- plifier network also contained within the hydrophone.

4739262

METHOD FOR REMOVAL OF BIAS DIFFERENCE BETWEEN

MAGNETOMETERS

James M Fleetwood assigned to Mobil Oil Cor- poration

A method for removing bias difference between two or more similarly operated magnetometers is disclosed wherein the inherent bias difference due to the magnetic field of the towing vessel is removed without determining its relative magnitude. Magnetic data is gathered and all time related magnetic events except bias level and slope of the time related magnetic events are removed by mathematical adjustment. Point by point statistical analysis is performed to remove the bias level and the time related slope.

SEA ANIMAL TRAP ASSEMBLY

John Jakimas assigned to Jakimas John; Jakimas Richard

There is disclosed a novel trap assembly in- cluding a spring-loaded body member positioned on and mounted to a base member whereby the body member is capable of raising up into an instant upright operational configura- tion. The novel trap assembly provided with side wall members hingeably mounted to the base member for encasing the body member during retrieval of the novel trap assembly.

4739858

SPECTRALLY-SHAPED AIR GUN ARRAYS

William H Dragoset assigned to Western Atlas International Inc

The invention is a method of shaping the spectrum of a seismic source signature. Energy is concentrated in the range below a selected fre- quency and attenuated in the range above the selected frequency by activating a plurality of sources asynchronously within a time window of selected duration. In a preferred embodiment, the frequency spectrum is smoothed by firing a second plurality of sources within a second time window having a time delay from the first time window equal to substantially the time between the initial firing of a source and the first positive zero-crossing of the signature.