James Howard Pratt

US Patent:

20050021285, Jan 27, 2005

Filed:

Jun 17, 2004

Appl. No.:

10/870682

Inventors:

Robert Troxler - Raleigh NC, US
James Pratt - Raleigh NC, US
Andrew Dummer - Durham NC, US

International Classification:

G01B011/28

US Classification:

702156000

Abstract:

An apparatus for determining a volume of a construction material sample is provided, comprising at least one sample-interacting device configured to interact with the construction material sample so as to determine at least one surface characteristic thereof. A computer device is configured to be capable of receiving the at least one surface characteristic from the at least one sample-interacting device, and to manipulate the at least one surface characteristic so as to form a three-dimensional representation of the construction material sample. The computer device is further configured to determine the volume of the construction material sample from the three-dimensional representation thereof. By determining the mass of the construction material sample, the density of the construction material sample can be provided. An associated method is also provided.

US Patent:

47916567, Dec 13, 1988

Filed:

Apr 16, 1987

Appl. No.:

7/039629

Inventors:

James D. Pratt - Raleigh NC
Ralph L. Ely - Durham NC

Assignee:

Troxler Electronic Laboratories, Inc. - Research Triangle Park NC

International Classification:

G06F 1552

US Classification:

378 89

Abstract:

Nuclear density gauges of the type having a gamma source which is positionable at several different source depth positions with respect to a detector are calibrated in an efficient and advantageous manner by a calibration procedure which reduces the number of experimental counts which must be taken. In accordance with the present invention, a single calibration block is employed and counts are taken at one or more source depth positions on the block. Through the use of historically derived relationships between the count rate obtained from the calibration block to the count rates obtained from at least two different calibration blocks of other known densities, the expected calibration counting rates for the other blocks can be obtained. These calculated counting rates are then used along with the experimentally determined counting rate to obtain the calibration constants for the gauge.

US Patent:

52586227, Nov 2, 1993

Filed:

Mar 13, 1992

Appl. No.:

7/850554

Inventors:

James D. Pratt - Raleigh NC

Assignee:

Troxler Electronic Laboratories, Inc. - Research Triangle Park NC

International Classification:

G01N 2300

US Classification:

25039005

Abstract:

An instrument and a method are provided for determining the moisture and cement contents of fresh concrete and for calculating and displaying to the user of the instrument the projected strength of the concrete. The instrument has two probes, each probe containing a low-activity nuclear source. The probes are stored in shielded receptacles in a housing when not in use. The user calibrates the probes with reference to concrete compositions of known cement and water content, and then for field use separately inserts each probe into the access tube of a sample pan filled with concrete to obtain counts corresponding to moisture content and cement content. An electronics unit is attached to the housing for storing the correlations and performing the calculations.