John A Willis

US Patent:

7388808, Jun 17, 2008

Filed:

Sep 23, 2004

Appl. No.:

10/947745

Inventors:

Shu-Schung Lee - Houston TX, US
John Willis - Houston TX, US
Yeashung Lin - Sugar Land TX, US

Assignee:

PGS Americas, Inc. - Houston TX

International Classification:

G01V 1/36

US Classification:

367 50, 367 51, 367 52, 367 53, 367 73

Abstract:

A method is disclosed for depth migrating seismic data. The method includes pre-stack time migrating the seismic data to form a stacked, time migrated image. The stacked, time migrated image is demigrated, and post-stack depth migration is then performed on the demigrated image. In some embodiments, the pre-stack time migration and the demigration account for ray bending in vertically transversely isotropic media.

US Patent:

39872467, Oct 19, 1976

Filed:

May 19, 1975

Appl. No.:

5/578480

Inventors:

John R. Willis - Houston TX

Assignee:

Electromitor, Inc. - Amelia LA

International Classification:

H04M 1104

US Classification:

179 2A

Abstract:

The apparatus disclosed is for use with conventional automatic dialing telephone equipment and includes a master or central station and a remote, automatically triggered, dialing station. The remote station is triggered by an alarm device of no particular interest to the present invention, such as one to indicate an intruder or a fire. The remote station, once triggered, electronically dials the assigned sequence of numbers by forming the necessary make and break signals for the conventional telephone equipment found at the telephone exchange to connect the remote station to the central station through the telephone system. When the connection is completed, the central station sends a tone pulse to the remote station to verify the completion of the connection. The remote station then transmits data to the central station by spaced tone pulses. Simultaneously with the receipt of each tone pulse, the central station sends a tone pulse to the remote station of a preselected amplitude and frequency having the same duration as the tone pulse from the remote station to verify receipt of the tone pulse.