Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Method and apparatus for determining compressional first arrival times from waveform threshold crossings provided by apparatus disposed in a sonic well tool










Image Number 15 for United States Patent #4985873.

A well logging system includes a digital threshold crossing data generation system (TCDG System) disposed in a well tool, adapted to be disposed in a borehole, and a digital first motion detection (DFMD) software disposed in a memory of a well truck computer. The TCDG system generates a series of threshold crossings for each analog signal received from a receiver of the well tool, the threshold crossings including a plurality of threshold crossing events for each analog signal and representing compressed versions of digitized analog waveforms. The well logging truck computer receives the threshold crossing data from the TCDG system and executes the DFMD software. When the software is executed, a first set of compressional wave first arrival times are determined from a startup routine in the software using the threshold crossing data. A second set of compressional wave first arrival times are determined from a tracking routine in the software using four different prediction methods and a voting procedure to select the second set of arrival times from among the four predictions. A cycle skip detection routine in the software determines if any cycle skips are associated with either the first or second set of compressional first arrival times. Finally, a cycle skip recovery routine determines which set of compressional first arrival times to select depending upon the outcome of the cycle skip detection routine.








 
 
  Recently Added Patents
Method for combining images and magnetic resonance scanner
Picture information coding device and coding method
Method of hydrothermal liquid phase sintering of ceramic materials and products derived therefrom
Systems of an electronic device and methods for manufacturing the same
Imaging device
Case for electronic device
Organic compounds
  Randomly Featured Patents
Liquid ejecting head, liquid ejecting head unit, liquid ejecting apparatus and method of manufacturing liquid ejecting head
Hydraulic tool with forward surrounding reservoir
Retroviral protease inhibitors
Apron fastener
Wet and dry tissue dispenser
Ventilated sliding closure assembly
Multilayer pulsed-current electrodeposition process
Print control apparatus, for performing a printing operation by reusing rendering completed data
[3-substituted-2-(substituted imino)-4-oxo-5-thiazolidinylidene]acetic acids having activity as leukotriene antagonists
Method of constructing a thin film mirror