DAVID ALLEN JOHNSON
Engineers in Littleton, CO

5566951, Oct 22, 1996

Jun 24, 1994

8/265303

Peter J. Dart - Boulder CO
Howard F. Hall - Longmont CO
David A. Johnson - Littleton CO

Dart International, Inc. - Englewood CO

F41J 914, F41J 514, A63B 7100

273358

An archery practice device projects a moving hunt scene on a screen. In one embodiment of the invention, a continuous plane of IR light is located prior to the screen, an arrow carrying a reflector is detected as it penetrates this light plane, and IR illumination is reflected back toward the archer and a full-screen radiation detector. In another embodiment, a piezoelectric motion detector senses impact of an arrow on the screen, an IR source is momentarily triggered by the motion detector, and IR illumination is reflected by the arrow toward the full-screen radiation detector. The detector generates a full-screen signal indicating the point of arrow impact on the screen. Upon detecting the arrow, the moving scene is frozen on the screen. The visual content of the frozen scene is coordinated to the full-screen signal from the detector, whereupon a hit zone image is projected on the screen to indicate the arrow impact point relative to the frozen scene. The arrow does not penetrate the screen, and drops vertically downward adjacent to the bottom of the screen at a location between the front of the screen and the archer.

5394732, Mar 7, 1995

Sep 10, 1993

8/119790

David A. Johnson - Littleton CO
Douglas P. Miller - Broomfield CO
Keith J. Manica - Lakewood CO
William M. Dormont - Boulder CO
Christopher J. Welsh - Fort Collins CO
William R. Mandel - Harlem MT

COBE Laboratories, Inc. - Lakewood CO

G01N 2902

73 191

Inclusions in a liquid flow, such as air bubbles in a blood flow, are detected by transmitting a signal through the fluid and receiving and interpreting the received signal based on the expected degree of attenuation for the liquid and the inclusions. The amplitude of the transmitted signal is automatically adjusted to maintain a constant average amplitude of the detected signal, thus compensating for changes in the detection environment. The average amplitude of the transmitted signal is controlled by integrating the received signal using an integrator with a time constant longer than the time constant of the expected inclusion signals, and comparing the integrated signal to a constant reference level. The presence of microbubbles is detected and a signal comprising a string of high frequency pulses is generated while the microbubbles are present. By counting the pulses, in conjunction with knowledge about the flow of liquid and the anticipated size of the microbubbles, an estimate of the total amount of air infused into the patient within a given time period is calculated.

4548702, Oct 22, 1985

Feb 24, 1984

6/583320

Earl D. York - Englewood CO
David M. Johnson - Littleton CO
Paul B. Miller - Odessa TX

Standard Oil Company - Chicago IL
Gulf Oil Corporation - Chicago IL

C10G 100

208 11R

A process is provided to produce, stabilize, dedust and upgrade synthetic oil, such as shale oil. In the process, synthetic fuels, such as oil shale, tar sands and diatomite are retorted with heat carrier material to liberate an effluent product stream comprising hydrocarbons and entrained particulates of dust. In order to minimize polymerization of the product stream and agglomerate the dust, the product stream is stabilized, upgraded, and pretreated prior to dedusting, in a hydroprocessor, such as an ebullated bed reactor, with a hydroprocessing gas in the presence of a catalyst. The hydroprocessing gas can be hydrogen, scrubbed fractionator gases, or hydrocarbon-enriched hydroprocessor off gases.

4216935, Aug 12, 1980

Mar 22, 1979

6/022744

Jerry K. Ellefson - Lakewood CO
David E. Johnson - Littleton CO

The Gates Rubber Company - Denver CO

A47G 2900

248360

A hanger for suspending hollow articles such as hose is described, having a pair of resilient legs including retention portions at the sides of the legs for frictionally engaging the inner wall of the article, a bracing portion for limiting movement of the legs, and a hanger portion configured to permit mounting the hanger on a support.