Larry W Colwell

US Patent:

54885612, Jan 30, 1996

Filed:

Mar 3, 1995

Appl. No.:

8/398598

Inventors:

Peter N. Berkowitz - Houston TX
Michael N. Papadopoulos - Houston TX
Larry W. Colwell - Friendswood TX
Martin K. Moran - Houston TX

Assignee:

Continental Controls, Inc. - Houston TX

International Classification:

G06F 1900
G05B 1302

US Classification:

364165

Abstract:

On-line control of a process is achieved by feedforward computations of manipulated variable setpoints modified during each of frequent optimization cycles by feedback trim determined by actual versus predicted effects of setpoint changes on the process controlled variables. Process, economic, contractual and equipment parameter values are continuously polled and collected and used to compute the optimal setpoints for the manipulated variables before the feedback trim is applied. Drift factors are added to the feedback trim to provide on-line calibration of key measuring instruments. Drifts in process performance are updated on-line periodically through self-tuning routines computed as calibration factors for predictor and control equations based on rigorous process simulations and actual plant performance. The equations take the form of polynomials in which each term contains an adjustable coefficient and one or more variable process parameter. The tuning factors are automatically applied at chosen time intervals to minimize the size of the feedback corrections computed during every optimization cycle.

US Patent:

49507206, Aug 21, 1990

Filed:

Apr 29, 1988

Appl. No.:

7/188260

Inventors:

James C. Randall - Seabrook TX
Ferdinand C. Stehling - Baytown TX
Michael C. Chen - Deer Park TX
Larry W. Colwell - Friendswood TX

Assignee:

Exxon Chemical Patents Inc. - Linden NJ

International Classification:

C08L 2312
C08L 2316
C08F29708

US Classification:

525322

Abstract:

A modified polypropylene having a substantially isotactic homopolypropylene and a propylene/olefin random copolymer, the modified polypropylene including up to about 50 chain disruptors per 1000 propylene repeat units. The chain disruptors are racemic polypropylene diads and olefin, the olefin being incorporated into the high end of the molecular weight distribution of the modified polypropylene.