Abstract: A three-lobe Root's blower is provided with feed back structure to bring the gas trapped in the impeller well volumes up to the discharge pressure prior to delivery. An essentially uniform and pulse-free discharge is produced by having a constant feed back flow rate which is achieved by always having a trapped impeller well volume in communication with the outlet via feed back structure which is sized to yield a continuous feed back flow rate.

Abstract: A modulating signal which is selectively changed as a function of time is applied to the modulating diodes of a retrodirective array. The diodes modulate the signal reflected from the array. A decoder coacting with the illuminating radar can extract information from the time-frequency code superimposed on the return signal to thereby identify the target.

Abstract: A forced hot air woodburning fireplace attachment including a blower, a header communicating with the blower and a plurality of generally C-shaped tubes each having one end connected to the header. The other end of the tubes facing away from the fireplace and towards a room to be heated and at least one of these ends having connected thereto a bypass conduit for delivering air directly to the fire.

Abstract: A stall control system for axial flow compressors incorporating: a plurality of pressure transducers for developing signals indicative of the nonsteady pressure variations within the compressor and wherein these signals are separately filtered and rectified; analog comparators and gate comparators for each such signal to develop an output indicative of the difference between each of the signals and an adjusted pressure reference signal which is derived from the pressure rise across the compressor; a logic circuit for generating an actuating signal if any one of such signals is higher than the reference signal for controlling the opening of a gate which passes the combined pressure signals to an integrator which develops an output control signal to take corrective action in the presence of rotating stall within the compressor: an adjustable time delay circuit providing long and short decay times to prevent over-control.

Abstract: Laser output from the fundamental, first overtone, and second overtone transitions in CO is achieved in a supersonic flow laser using an electric-discharge-excited CO/He/O.sub.2 mixture.

Abstract: A method for locatingweak targets such as power lines and tree tops in the presence of terrain clutter by separating the weak target from the clutter in the elevation plane.

Abstract: A remote controlled automobile door opening system having solenoid assemblies for unlocking, unlatching and partially opening the automobile door in response to a remote radio signal. The unlocking, unlatching and partial opening of the door occur sequentially after the radio signal is received.

Abstract: A demountable, rectangular, liquid sample flow cell is provided which can be used to make streaming potential or streaming current measurements from which the zeta potential is calculated. By providing an infrared transparent window in the flow cell, a real-time monitoring of surface deposition rates and amounts can be determined by infrared radiometry. Because the flow cell is completely demountable, direct analysis of the internal surfaces exposed to the flowing solution is possible.

Abstract: The dispensing of the chaff fibers takes place in two distinct steps. Initially, a mixture of chaff and fluidization media is delivered to a fluidization chamber. Bleed air from the jet engines is caused to flow through the mixture of chaff and fluidization media to thereby cause the chaff fibers to churn and become separated in the fluidization chamber. Valves located at the ends of the fluidization chamber open in response to pilot or onboard ECM system activation to dispense the pre-separated chaff fibers.

Abstract: A sintered projectile having the same ballistic characteristics as a conventional combat projectile is provided with controlled strength properties and predetermined breakage lines. As a result, small, high drag fragments are produced on impact which minimizes ricochet hazards and provides a safer practice round.

Abstract: Distance is measured with a tone modulated AM radio system by making a signal at the ranging tone frequency phase coherent with respect to the modulation on the RF signal at the input to the receiver by means of a product detector located ahead of the receiver of the transponder. In this way, a ranging tone phase is established which is a direct and accurate measure of the modulation phase (delayed by the propagation time) and is independent of any modulation phase shifts experienced in the receiver.

Abstract: Thermal radiation, or any incoherent radiation at the desired wavelenths, is converted into laser energy by using radiant absorption from a radiation source by a cold gas. The cold gas absorbs vibrational energy while remaining otherwise cold, and exchange of vibrational energy between molecules at this low temperature causes population inversions.

Abstract: A phase coherent canceller for jamming suppression is provided with a variable controlled oscillator which is locked in frequency and phase to a reference local oscillator in a closed loop configuration.

Abstract: When using CO as the absorbing and lasing species for vibration-vibration energy transfer and subsequent vibration-vibration pumping, CO can be made to dissociate and subsequently form C.sub.2 with isotope separation, or CO may be made to chemically react with N.sub.2 to produce CN with isotope separation.

Abstract: A catch basin may be retrofit for isolating/diverting spills and/or initial storm runoff for the subsequent treatment or recycling of the collected material. A sloping, peripheral trough is provided in the catch basin and is connected to one or more storage or recovery tanks or the like. A plurality of catch basins may be provided with troughs connected to one or more common storage or recovery tanks.

Abstract: The electrical and mass efficiencies of an electrically excited flowing gas laser are improved by lining the discharge tube with a filler which minimizes the regions of slow or recirculating gas flow, and by utilizing a wire anode gas injector to feed laser gases into the discharge.

Abstract: A chaff cartridge is made up of a plurality of chaff interpackets contained in subprojectiles. The subprojectiles are each provided with fins and the fins of each subprojectile in a chaff cartridge provide a different drag to cause the spacing out of the subprojectiles. The fins, additionally, cause the subprojectiles to rotate and thereby radially disperse the chaff.

Abstract: The generation of visible or ultraviolet chemical laser radiation is achieved by the vapor phase combustion of metal atoms. The vapor is formed in a precombustor and metal vapor is extracted from the precombustor and fed via a supersonic nozzle to the laser cavity where it is reacted with an oxidant to produce excited molecules and thereby lasing.

Abstract: The quality of and/or transmission speed for fingerprint facsimiles transmitted over telephone lines are improved by image enhancement prior to transmission. Image enhancement is achieved by using a multi-element photodetector array and simultaneously processing the signals from the component elements of the multi-element photodetector to produce a binary video output indicating whether the center of the scan is on a ridge or a valley portion of the fingerprint.