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Frazer, R. E.

Publications and source records attributed to Frazer, R. E..

At least 19 records

Self-Identifying Reflecting Targets

Proposed scheme for target identification requires no radiation of energy by target itself. Instead, target alters light beam reflected from itself back to interrogating station in unique way. Interrogator then identifies target from its signature impressed on returned beam. Selfidentifying target useful in surveying, navigation, and remote monitoring (for example, of mountain-climbing parties.)

Frazer, R. E.

Probe Follower for Moving Blood Vessels

Probes track vessel expansion and contraction with minimal perturbation. Nozzle back-pressure changes at cuff on blood vessel basis for monitoring position of probe in blood vessel. Fluidic amplifiers use signals to control three-axis servo that centers measuring probe between sensing-nozzle pairs at cuff.

Frazer, R. E.

Inflight Assay of Red Blood Cell Deformability

Studies on Soviet and American astronauts have demonstrated that red blood cell production is altered in response to low gravity (g) environment. This is associated with changes in individual red cells including increased mean cell volume and altered membrane deformability. During long orbital missions, there is a tendency for the red cell mass deficit to be at least partly corrected although the cell shape anomalies are not. Data currently available suggest that the observed decrease in red cell mass is the result of sudden suppression of erythropoieses and that the recovery trend observed during long missions reflects re-establishment of erythropoietic homeostasis at a "set point" for the red cell mass that is slightly below the normal level at 1 g.

Ingram, M.

Continous Monitoring of Melt Composition

Compositions of glasses and alloys analyzed and corrected in real time. Spectral analysis and temperature measurement performed simultaneously on molten material in container, such as open-hearth furnace, crucible or tank of continuous furnace. Speed of analysis makes it possible to quickly measure concentration of volatile elements depleted by prolonged heating.

Frazer, R. E.

Constant magnification optical tracking system

A constant magnification optical tracking system for continuously tracking of a moving object is described. In the tracking system, a traveling objective lens maintains a fixed relationship with an object to be optically tracked. The objective lens was chosen to provide a collimated light beam oriented in the direction of travel of the moving object. A reflective surface is attached to the traveling objective lens for reflecting an image of the moving object. The object to be tracked is a free-falling object which is located at the focal point of the objective lens for at least a portion of its free-fall path. A motor and control means is provided for mantaining the traveling objective lens in a fixed relationship relative to the free-falling object, thereby keeping the free-falling object at the focal point and centered on the axis of the traveling objective lens throughout its entire free-fall path.

Frazer, R. E.

Imager displays free fall in stop action

Microprocessor-controlled imaging system displays sequence of "frozen" images of free-falling object, using video cameras positioned along fall. Strobe lights flash as object passes each camera's viewfield. Sequence stored on video disk and displayed on television monitor is stop-action record of fall dynamics. With modification, system monitiors other high speed phenomena.

Frazer, R. E.

Tracking falling objects

Moving lens follows movement of object accelerated by gravity. Lenses and mirrors maintain constant magnification regardless of distance between moving optical carriage mechanism and fixed telescope. Device tracks objects up to 2 cm in diameter over vertical distance of 2 m.

Frazer, R. E.

Strong thin membrane structure

A continuous process is described for producing strong lightweight structures for use as solar sails for spacecraft propulsion by radiation pressure. A thin reflective coating, such as aluminum, is applied to a rotating cylinder. A nylon mesh, applied over the aluminum coating, is then coated with a polymerizing material such as a para-xylylene monomer gas to polymerize as a film bound to the mesh and the aluminum. An emissivity increasing material such as chromium or silicon monoxide is applied to the polymer film to disperse such material colloidally into the growing polymer film, or to the final polymer film. The resulting membrane structure is then removed from the cylinder. Alternately, the membrane structure can be formed by etching a substrate in the form of an organic film such as a polymide, or a metal foil, to remove material from the substrate and reduce its thickness. A thin reflective coating (aluminum) is applied on one side of the substrate, and an emissivity increasing coating is applied on the reverse side of the substrate.

Frazer, R. E.

Apparatus for endoscopic examination

An endoscope is having a propulsion mechanism and at least one transmitter at the distal end transmitting bursts of energy waves (radio frequency or ultrasonic) for tracking the position of the distal end through the use of two or more transducers on the anterior or lateral surfaces of a patient is described. The propulsion mechanism which consists of two radially expandable bladders separated by an axially expandable bellows with only the forward bladder attached to the distal end is discussed. Alternate mechanisms are reported. A sheath on the endoscope which includes material having a sharp melting point slightly above body temperature so that the sheath is made flexible at selected sections by applying current to separate heating wires in the sections of the sheath is described.

Frazer, R. E.

Room-temperature bonding of thin plastic sheets

Thin sheets of plastic are bonded together, without heat, by depositing metal films on plastic and applying light pressure. Films are pressed together at room temperature, technique which makes it possible to join organic material without high temperatures necessary for conventional adhesive bonding.

Frazer, R. E.

Improved probe for rectal-cancer detection

Modified protosigmoidoscope, with third partially mirrored lens, provides lateral as well as forward vision for thorough examination of patients for malignant or premalignant lesions of colon and rectum.

Frazer, R. E.

Coupling apparatus for ultrasonic medical diagnostic system

An apparatus for the ultrasonic scanning of a breast or other tissue is reported that contains a cavity for receiving the breast, a vacuum for drawing the breast into intimate contact with the walls of the cavity, and transducers coupled through a fluid to the cavity to transmit sound waves through the breast. Each transducer lies at the end of a tapered chamber which has flexible walls and which is filled with fluid, so that the transducer can be moved in a raster pattern while the chamber walls flex accordingly, with sound transmission always occurring through the fluid.

Frazer, R. E.

A probe for blood-vessel and spinal interiors

Probe design allows insertion into lumen of blood vessels to perform oximetry and investigate plaque on interior vessel walls. Probe is more accurate than standard oximetry procedures of determining oxygenation of circulating blood.

Frazer, R. E.

In vivo blood-flow mapping

Application of laser doppler techniques to commercially available, low loss fiber optics allows direct reading of blood velocity within tiny blood vessels.

Frazer, R. E.

Ultrasonic-mammography apparatus

Improved transmitted/tissue/receiver coupling enhances sensitivity of mammography test. Device involves chamber into which organ is inserted or drawn by vacuum.

Buchea, O. C.

Biological-activity monitor

Ingested fluorescent precursors are tracked after excretion as fluorescent compounds, to monitor activities ranging from metabolism to migration.

Frazer, R. E.

Feasibility study on the design of a probe for rectal cancer detection

Rectal examination techniques are considered in terms of detection capability, patient acceptance, and cost reduction. A review of existing clinical techniques are considered in terms of detection capability, patient acceptance, and cost reduction. A review of existing clinical techniques and of relevant aerospace technology included evaluation of the applicability of visual, thermal, ultrasound, and radioisotope modalities of examination. The desired improvements can be obtained by redesigning the proctosigmoidoscope to have reduced size, additional visibility, and the capability of readily providing a color photograph of the entire rectosigmoid mucosa in a single composite view.

Anselm, V. J.